Microbiological Aspects of Food Quality and Safety

8/16/2019 Microbiological Aspects of Food Quality and Safety

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C!"#!"$

1. T%&!'() R*#) %!+ $,!,,%!# ',%!,$'$ ,! + .................... ...................... ................

2. I!",!$, %!+ #&",!$, %%'#"#$ +$ "%" %#" ',3,%* " .............................. --.-. /o(st$re content ................................................................................................................................................ --

.. *0 ............................................................................................................................................................................. -1

.. 23(%at(on–re%$ct(on *otent(al ..................... ...................... ...................... .................... ...................... .......... -4

.1. 5$tr(ent content ................................................................................................................................................. -6

.7. Sal(n(t" .................................................................................................................................................................... 8

.4. Ph"s(cal an% b(olo)(cal str$ct$res ..................... ...................... ..................... ..................... ...................... ... 8

.9. :em*erat$re of stora)e .................................................................................................................................. -

.;. 2smot(c *ress$re ...............................................................................................................................................

.6. lostr(%($m *erfr(n)ens foo% *o(son(n) ....................... ..................... ..................... ...................... ... 18

... >lostr(%($m bot$l(n$m foo% *o(son(n) ?bot$l(sm@ .................................. ..................... .............. 1

5.4. Salmonella #!6$ %!+ +3!# %$"#!"#,",$ %6$#+ 3( Salmonella ........................ 19

5.. Escherichia coli %!+ +3!# %$"#!"#,",$ %6$#+ 3( Escherichia coli ................... 7

5.9. Shigella #!6$ %!+ $,#**$,$ ................................................................................................................. 7;

5.:. Yersinia #!6$ %!+ (#$,!,$,$ ................................................................................................................ 4-

5.8. Vibrio #!6$ %!+ 7,3,$,$ ......................................................................................................................... 4

5.;. Campylobacter #!6$ %!+ %'(*3%"#,$,$ ..................... ...................... ..................... .............. 44

5.10. M("&,#!, 6!, %!+ '("&,!$ ............................................................................................... 46

5.11. F+3!# V,6$#$ ...................................................................................................................................... 97

5.12. F+3!# %%$,"#$ .................................................................................................................................. 9;

4. M,%!,$'$ ,! %!,'%* +6"$............................................................................................................. ;9

. M,%!,$'$ ,! *%!" +6"$ ................................................................................................................ 64

R###!#$ ..................................................................................................................................................................... -81


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1. T AonseC$entl" foo%s are rarel" ster(le. 0oBe#er th(sm(croflora %oes ne(ther chan)e the *h"s(cal or chem(cal character(st(c of the foo%, nor ca$se%(sease (n most cases. :he m(crob(al *resence (s %etectable Bhen the" ca$se s*o(la)e, orfoo%borne (llness. /(crob(al act(#(t" not onl" %ecreases the C$al(t" of the foo%, b$t can e#en beharmf$l for the cons$mers. :he safet" of a )(#en foo% *ro%$ct base% on total m(crob(al n$mbers?*er )ram or m(ll(l(ter@, an% the t"*e of m(crobes as Bell. e can then *re%(ct the )eneral t"*esof m(croor)an(sms to be e3*ecte% on a *art(c$lar foo%, (n case Be noB the t"*es ofm(croor)an(sms assoc(ate% B(th *lant an% an(mal foo%s (n the(r nat$ral states. :hem(crob(olo)(cal safet" an% C$al(t" of a foo% (s %eterm(ne% b" the *ro*ert" of the foo%, them(crob(al contam(nat(on of the raB mater(als, the *ro%$ct(on technolo)", an% the stora)e an%*aca)(n) con%(t(ons.

/(crobes can also *la" a *os(t(#e role (n foo%. :he" can be cons$me% as foo%s (n themsel#es as (nthe e%(ble f$n)(, m"co*rote(n an% al)ae. :he" can also effect %es(rable transformat(ons (n a foo%%$r(n) fermentat(on *rocesses, chan)(n) (ts *ro*ert(es (n a Ba" that (s benef(c(al.

B%"#,%* "%&!'(

=acter(al ta3onom" has chan)e% s$bstant(all" (n the *ast feB %eca%es. Se#eral neB ta3a ha#e

been create% as a res$lt of the em*lo"ment of molec$lar )enet(c metho%s. :hree (n%s ofmetho%s are $se% for the (%ent(f(cat(on an% %escr(*t(on of bacter(aA ?(@ *henot"*(c, ?((@ )enot"*(c,an% ?(((@ *h"lo)enet(c. Phenot"*(c an% )enot"*(c anal"s(s are )ro$* or)an(sms base% on the(rs(m(lar(t(es, Ph"lo)enet(c anal"s(s (s *lace or)an(sms B(th(n an e#ol$t(onar" frameBor, an%com*lement the *re#(o$s metho%s.

P#!"(, %!%*($,$ e3am(nes the mor*holo)(cal, metabol(c, *h"s(olo)(cal, serolo)(cal an%chem(cal character(st(cs of the cell.

/or*holo)(cal characters (ncl$%e colon" mor*holo)" ram react(on cell s(ze an% sha*e*attern of fla)ellat(on *resence of s*ores, (ncl$s(on bo%(es ca*s$les, S!la"ers or sl(me la"ers.

:he ram!sta(n(n) base% character(zat(on (s one of the ol%est an% most B(%es*rea% metho%s for)ro$*(n) bacter(a.

:he st$%" of bacter(al metabol(c character(st(cs (n foo% m(crob(olo)" refers to $t(l(zat(on of(n%(#(%$al carbon, n(tro)en, or s$lf$r com*o$n%s fermentat(on of s$)ars n(tro)en f(3at(on)roBth factor reC$(rements.

:em*erat$re, *0, an% salt ran)es for )roBth res*onse to o3")en ?e.). aerob(c, fac$ltat(#e,anaerob(c@ *resence of catalase or o3(%ase *ro%$ct(on of e3tracell$lar enz"mes belon) tost$%(e% *h"s(olo)(cal character(st(cs.

>ell$lar fatt" ac(% *rof(le (%ent(f(cat(on ?F'/EA fatt" ac(% meth"l ester@ (s B(%es*rea% (nlaborator(es Bhere h$man *atho)ens ro$t(nel" m$st be (%ent(f(e% ?cl(n(cal, *$bl(c health, foo%


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an% Bater!(ns*ect(on@. :he fatt" ac(% com*os(t(on ?cha(n len)th, *resence or absence of %o$blebon%s, r(n)s, branche% cha(ns, or h"%ro3" )ro$*s@ of =acter(a #ar(es from s*ec(es to s*ec(es.

G#!"(, %!%*($,$ cons(%ers character(st(cs of the )enome B(th metho%s l(e D5'h"br(%(zat(on an% G > content of D5' S, -4S, an% 7S r rat(os %(ffer b" more than abo$t 7J, tBo or)an(smsH are $nl(el" to be closel" relate%.

:a3onom(c (nformat(on can be obta(ne% from the %eterm(nat(on of rarl oese establ(shment of three %oma(n of l(fe ?E$ar"otes,'rchaebacter(a, an% Proar"otes@ base% on -4S r


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F,6# 1.2= :he *h"lo)enet(c tree of l(fe, base% on -4-;S r


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F,6# 1.5= Some ma+or *h"la of =acter(a base% on -4S r(bosomal > 77J. :he later (ncl$%es the )eneraStreptomyces, Propionibacterium, Micrococcus, Bifidobacterium, Corynebacterium,Brevibacterium. :he F(rm(c$tes )ro$* (ncl$%e the )enera Clostridium, Bacillus, Staphylococcus,Lactobacillus, Pediococcus, Leuconostoc, an% Listeria.:he ram!ne)at(#e Proteobacter(a (s the other *h"l$m B(th (m*ortance (n foo% m(crob(olo)".=ase% on -4S r


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Pseudoalteromonas, Pseudomonas, Psychrobacter, Photobacterium,She/anella, Stenotrophomonas, *ibrio, "anthomonas, "ylella.

Delta*roteobacter(aA Campylobacter, &elicobacter

/ost foo%borne bacter(a ?es*ec(all" foo%borne *atho)ens@ belon) to the Q –s$bclass.

F6!%* "%&!'(

F$n)( are a lar)e, %(#erse, an% B(%es*rea% )ro$* of or)an(sms, cons(st(n) of the mo$l%s,m$shrooms, an% "easts.

Y#%$"$ )roB as s(n)le!celle% forms.

M6*+$ are m$lt(cell$lar, form(n) a netBor of f(laments from t$b$lar cell, s$rro$n%e% b" Balls,calle% h"*hae ?F(). -.1@.

F,6# 1.4= :he schemat(c %raB of a h"*ha

Se*tate f$n)al h"*hae ha#e cross!Balls, Bh(ch are se*arat(n) cells. :here are no cross!Balls (n

the coenoc"t(c h"*ha. In th(s case #e)etat(#e cell of a f$n)al h"*ha conta(ns more than onen$cle$s ?F(). -.7@. Each h"*hal f(lament )roBs ma(nl" at the t(* b" e3tens(on of the term(nal cell.

F,6# 1.= Schemat(c %raB of the se*tate an% coenoc"t(c h"*ha of f$n)( ?So$rceAhtt*ABBB.chesterf(el%.-.sc.$scheraBJ8(nterme%(ateDa#eE#ans=(olo)"II0"*haeJ8D(a).+*)

?>hesterf(el%A =(olo)" II@, %oBnloa% t(meA --.-.8-1.@

0"*hae t"*(call" )roB to)ether form(n) a #(s(ble t$ft calle% a m"cel($m. From the m"cel($m

)roB(n) o#er an% (nto the or)an(c mater(al, h"*hal branches form aer(al h"*hae abo#e thes$rface, an% ase3$al s*ores are forme% on these branches ?F(). -.4@. 'se3$al s*ores are forme%


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B(tho$t f$s(on of )ametes or me(os(s, an% ha#e se#eral t"*es an% f$nct(on to %(s*erse the f$n)$sto neB hab(tats.

F,6# 1.9= 0"*hae B(th aer(al m"cel(a an% ase3$al s*ores ?So$rceAhtt*ABBB.ats$.e%$fac$lt"chamberla(nebs(teLectsF$n)(.htmR)en ?Dr. :r(tzA /e%(cal /(crob(olo)" Fall

888@, %oBnloa% t(meA --.-.8-1.@

>on(%(a are forme% on con(%(o*hores an% the" are often *()mente% ?blac, bl$e )reen, re%,"elloB, or broBn@, an% )(#e the m"cel($m a %$st" a**earance. S*oran)(os*ores are forme%(ns(%e s*oran)($m. Some f$n)( form macrosco*(c re*ro%$ct(#e str$ct$res calle% fr$(t(n) bo%(es.F$n)( ma" also *ro%$ce se3$al s*ores as a res$lt of se3$al re*ro%$ct(on. De*en%(n) on the)ro$*, %(fferent t"*es of se3$al s*ores ?ascos*ores, z")os*ores, bas(%(os*ores@ are *ro%$ce%.

F$n)al ta3onom" has mare%l" chan)e% (n the *ast %eca%es, s(m(larl" to the bacter(al one. :heearl(er *re%om(nant mor*holo)(cal (%ent(f(cat(on has been ref(ne% B(th D5'!base% metho%s.:he most (m*ortant *h"lo)enet(c molec$lar marer (s the r


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:he F() -.9 shoBs the latest, acce*te% *h"lo)enet(c tree of F$n)(, base% on m$lt( )ene seC$enceanal"s(s.

:he former O")om"cota ta3on has s*l(t (nto %(fferent )ro$*s. :he (hi0opus, Mucor an%)hamnidium )en$s B(th foo% m(crob(olo)" (nterests are )ro$*e% (n the neBl" forme%

/$corom"cot(na s$b*h"ll$m. It can be character(ze% B(th coenoc(t(c h"*hae an% ase3$als*oran)(os*ores, an% se3$al z")os*ores. :he" are B(%es*rea% on so(l, %ea% *lant mater(als an%foo%s. Some (hi0opus s*ec(es ca$se Mblac s*ot& of beef, an% ma" be fo$n% on bacon an% other*rocesse% meats. (2 stolonifer (s one of the most common s*ec(es (n foo%s. It (s also referre% to asMbrea% mol%s&, an% *ro%$ce Bater" soft rot of fr$(ts ?a**les, *ears, stone fr$(ts, )ra*es, f()s@. (2oligosporus (s (m*ortant (n the *ro%$ct(on of s*ec(al fermente% foo%s ?oncom, bon)re, an%tem*eh@.

' neB s$b(n)%om, D(ar"a conta(ns 'scom"cota an% =as"%(om(cota *h"la. :he formerDe$terom"cota ?or F$n)( Im*erfect(@ ta3on of ase3$al f$n)( %oes not e3(st an"more s*ec(es hasbeen (nte)rate% to the 'scom"cota an% =as(%(om"cota )ro$*s, an% referre% as con(%(al f$n)(.:he(r h"*hae ha#e se*tae, an% %(ar"ot(c cell forms can be %etecte% *r(or to ar"o)am" an%me(os(s.

:he ascom"cetes, s*ec(es *ro%$ce se3$al ascos*ores (n asc(. In some ascom"cetes, the asc( areforme% B(th(n a fr$(t(n) bo%", calle% an ascocar*. :he" also *ro%$ce ase3$al s*ores, calle%con(%(a. :here are three s$b*h"la (n 'scom"cot(naA :a*hr"nom"cot(na, Saccharom"cot(na an%Pez(zom"cot(na.

:he "easts )en$s Schi0osaccharomyces belon) to :a*hr"nom"cot(na s$b*h"ll$m, an% %(#(%e b"lateral f(ss(on of cross!Ball format(on. :he most *re#alent s*ec(es, S2 pombe, (s osmo*h(l(c an%

res(stant to some chem(cal *reser#at(#es.

F,6# 1.8= :he b$%%(n) of Saccharomyces cerevisiae ?So$rceA htt*Asc(encefor(%s.(%(*e%e.comb(olo)"cells"east.htm ?east for (%s@ E#ol$t(onar" b(olo)"A '

(n)%om re#(se%@, %oBnloa% t(meA --.-.8-1.@

:he ma+or(t" of "east (s (n Saccharom"cot(na s$b*h"l$m, Bh(ch conta(ns b$%%(n) "easts. :he"m$lt(*l" b" b$%%(n) ?F(). -.;@. /ost (m*ortant )enera areA .luyveromyces, Saccharomyces,

)orulaspora, #ygosaccharomyces (n Saccharom"cetaceae fam(l", moreo#er &anseniaspora,ebaryomyces, Pichia. :he most (m*ortant ase3$al ?con(%(al@ "east )enera are Brettanomyces,


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Candida, Cryptococcus, (hodotorula, and )richosporon. :he baersH, breBersH, B(ne, an%cham*a)ne "easts are S2 cerevisiae. :he" are fo$n% (n ef(r )ra(ns an% can be (solate% from aB(%e ran)e of foo%s, s$ch as %r"!c$re% salam( an% n$mero$s fr$(ts.

Per(z(m"cot(na s$bh"ll$m conta(ns the mo$l%s B(th se*tate h"*hae. :he most (m*ortant )enera

(n foo% m(crob(olo)" areA Byssochlamys, -mericella, -upenicillium, -urotium ?E$rot(ales or%o,:r(chocomaceae fam(l"@. >on(%(al )enera areA Alternaria, Aspergillus, Aureobasidium, Botrytis,Cladosporium, 1usarium, !eotrichum, Monilia, Penicillium, )richothecium. :he sha*e of thecon(%(o*hores an% the Ba" of con(%(a *ro%$ct(on are character(st(c to )enera ?F(). -.6@.

F,6# 1.;= :he character(st(c ase3$al s*ore format(on of some (m*ortant m(tos*or(c f$n)(?So$rceA htt*Am"cota!crcc.mnhn.frs(te)enre.*h*lan)Ten) ?/"cotaA f$n)al contam(nats of c$lt$ral her(ta)e@,

%oBnloa% t(meA --.-.8-1.@

Alternaria

Aspergillus

Aureobasidium

Botrytis

Cladosporium

Fusarium Geotrichum Monilia Penicillium richothecium


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2. INTRINSIC AND EAT AFFECTMICROBIAL GRO?T>

I!",!$, %%'#"#$ Intr(ns(c *arameters are an (nse*arable *art of *lant an% an(mal t(ss$es. Intr(ns(c *arametersare mo(st$re content, *0, re%$ct(on *otent(al, n$tr(ent content, sal(n(t", *h"s(cal an% b(olo)(calstr$ct$res.Each of these factors (s %(sc$sse% beloB, an% Be *lace% the em*has(s on the(r effects onm(croor)an(sms (n foo%s.

.-. /2IS:U25:E5:

L(fe (s lar)el" %e*en%ent on the *resence of Bater.:he Bater reC$(rements of m(croor)an(sms are often %escr(be% (n terms of the Bater act(#(t"?aB@ (n the en#(ronment. ater act(#(t" (s a meas$re of the a#a(lable Bater (n a foo%. 5ormall"the mo(st$re content can be e3chan)e% betBeen the *ro%$ct an% the en#(ronment.

:here (s a non!l(near relat(onsh(* betBeen the Bater act(#(t" an% Bater content. :h(srelat(onsh(* (s also noBn as a mo(st$re sor*t(on (sotherm c$r#e. :h(s (sotherm (s s*ec(f(c totem*erat$re an% s$bstance. It can hel* to est(mate the stab(l(t" of *ro%$cts (n %(fferent stora)econ%(t(ons as t(me *asses.

ater act(#(t" (s %ef(ne% b" the rat(o of the Bater #a*or *ress$re of foo% s$bstrate ?*@ to the

#a*or *ress$re of *$re Bater ?*8@ at the same tem*erat$reA

aB T **8,

Bhere * (s the #a*or *ress$re of the sol$t(on, an% *8 (s the #a*or *ress$re of the sol#ent ?$s$all"Bater@.

Dr"(n) or %es(ccat(on (s one of the ol%est metho%s of *reser#(n) foo%s.:he effects of loBer(n) Bater act(#(t" ?aB@ beloB o*t(m$m areA

- (ncrease the len)th of the la) *hase of )roBth,- %ecrease the )roBth rate,- %ecrease the s(ze of f(nal *o*$lat(on.

ater act(#(t" (s (nfl$ence% b" other en#(ronmental *arameters ?e.). tem*erat$re of )roBth, *0,an% Eh@.

ater act(#(t" (s a coll()at(#e *ro*ert", beca$se (t %e*en%s on the n$mber of molec$les or (ons*resent (n sol$t(on, rather than the(r s(ze. For e3am*le so%($m chlor(%e ?Bh(ch %(ssoc(ates (ntotBo (ons (n sol$t(on@, (s more effect(#e at re%$c(n) the Bater act(#(t" than a com*o$n% l(es$crose.

:he Bater act(#(t" of *$re Bater (s -.88, Bh(le the aB of J 5a>l sol$t(on ?B#@ (s 8.;4 ?:able.-.-@. :he Bater act(#(t" of sat$rate% 5a>l sol$t(on (s 8.97.


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:able .-.-A


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:able .-.A /(n(m$m Bater act(#(t(es at Bh(ch act(#e )roBth can occ$r

?Va" et al, 887 '%am–/oss, 88;@

G6 ',%!,$'$ ',!,'6' % 7%*6#

/ost ram!ne)at(#e bacter(a 8.69/ost ram!*os(t(#e bacter(a 8.68

/ost s*o(la)e bacter(a 8.68

/ost s*o(la)e "easts 8.;;

/ost s*o(la)e mo$l%s 8.;8

0alo*h(l(c bacter(a 8.97

2smo*h(l(c "east 8.4-

Zero*h(l(c mo$l%s 8.4-

Staphylococcus aureus (s $n(C$e amon) foo%borne *atho)ens, beca$se some stra(ns can )roB ata m(n(m$m Bater act(#(t" of abo$t 8.;4, b$t to3(n *ro%$ct(on ma" reC$(re more fa#o$rablecon%(t(ons./ost s*ore!form(n) bacter(a %o not )roB beloB Bater act(#(t" of 8.6. S*ore )erm(nat(on an%o$t)roBth of Bacillus cereus (s *re#ente% at Bater act(#(t" of 8.69 to 8.6. :he m(n(m$m Bateract(#(t" for Clostridium perfringens s*ore )erm(nat(on an% )roBth (s betBeen 8.69 an% 8.67. :hem(n(m$m Bater act(#(t" for )roBth of Clostridium botulinum (s abo#e 8.61 ?:able .-.@.

:able .-.A '**ro3(mate m(n(m$m aB #al$es for )roBth of m(croor)an(sms ?Va" et al., 887@

M,%!,$'$ M,!,'6' % 7%*6#$

-scherichia coli 8,64

Bacillus subtilis 8,67Clostridium botulinum 8,61!8,69

Staphylococcus aureus 8,;4

Penicillium s**. 8,96!8,;

Aspergillus s**. 8,41!8,98

#ygosaccharomyces rou$ii 8,4

"eromyces bisporus 8,4-

ater act(#(t" of most fresh foo% ?e.). #e)etables, fr$(t, meat, f(sh, m(l, etc.@ (s abo#e 8.6;. Dr(e%*ro%$cts ?e.). m(l *oB%er, %r" *asta, %r(e% fr$(t, etc.@, as Bell as h()h!s$)ar *ro%$cts ?e.). +ams@

ha#e loB Bater content ?:able .-.1@.

:able .-.1A /(n(m$m aB #al$es of some foo%s ?


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.. P0

*0 (s the ne)at(#e lo)ar(thm of the h"%ro)en (on act(#(t". *0 9 (n%(cate ne$tral en#(ronment, *0#al$es beloB 9 (n%(cate ac(%(c, an% those abo#e 9 (n%(cate alal(ne en#(ronment.:he *0 of the en#(ronment has (nfl$ence on the )roBth an% metabol(sm of m(croor)an(sms.

Effect of *0 (s #er" stron) an% %(fferent(ate%. :he *0 has an effect on the electr(c char)e of the*lasma membrane *rote(ns, an% (t can alter the *ermeab(l(t" of the *lasma membrane.:he *0 tolerance of m(croor)an(sms can be character(ze% b" three *arameters ?m(n(m$m,ma3(m$m an% o*t(m$m *0 #al$e@.:he m(croor)an(sms are able to )roB (n the *0 ran)e from -.7 to --.8. /o$l%s can )roB (n theB(%est *0 ran)e ?-.7 to --.8@, b$t "east has also a B(%e s*ectr$m of *0 ?. to ;.7@ ?:able ..-@.:he o*t(m$m *0 ran)e for most bacter(a (s 4.8–;.8, for "easts (s 1.7–4.8, an% for mo$l%s (s .7–1.8.

:able ..-A *0 ran)e of m(croor)an(smsH )roBth ?Deá, 884 Szabó, 88;@

M,%!,$'$ M,!,'6' O",'6' M%&,'6'

/ost bacter(a 1.8 4.7 ;.7Lact(c ac(% bacter(a . 7.8 9.;

'cet(c ac(% bacter(a .; 1.8 7.7

easts . 7.8 ;.7

/o$l%s -.7 7.8 --.8

Se#eral m(croor)an(sms Bh(ch ma" ca$se foo%borne %(sease or foo% s*o(la)e are able to )roB atloB *0 #al$es ?:able ..@. :he m(n(m$m *0 for the )roBth of #ygosaccharomyces bailii (s -.;,for the )roBth of Alicyclobacillus acidocaldarius an% Botrytis cinerea (s .8, for the )roBth ofStaphylococcus aureus an% salmonellae (s 1.8.

:able ..A /(n(m$m *0 #al$es for the )roBth of some m(croor)an(sms ?Va" et al., 887@M,%!,$'$ M,!,'6' > 7%*6#

Shigella sonnei 7.8!1.7

Clostridium perfringens 7.8

Bacillus cereus 1.6

*ibrio parahaemolyticus 1.;

Clostridium botulinum I. cso*ort 1.4

-scherichia coli 8-79A09 1.7

Lactococcus lactis 1.

3ersinia enterocolitica 1.

Listeria monocytogenes 1.-

Salmonella s**. 1.8

Staphylococcus aureus 1.8

Lactobacillus brevis .-

Lactobacillus sa%ei .8

Penicillium ro4ueforti .8

Botrytis cinerea .8

Alicyclobacillus acidocaldarius .8

#ygosaccharomyces bailii -.;


15/109

2n the bas(s of the(r *0 tolerance m(croor)an(sms can be class(f(e% (nto ne$tro*h(l(c,ac(%o*h(l(c, an% alalo*h(l(c )ro$*.2*t(m$m *0 for !#6",*, m(croor)an(sms (s betBeen 7.7 an% ;.8. :he" occ$r (n nat$reB(%el" ?(ncl$%es most bacter(a, e.). -scherichia coli@.:he %,+,*, m(croor)an(sms )roB o*t(mall" beloB *0 7.7 ?e.). lact(c ac(% an% acet(c ac(%bacter(a, Alicyclobacillus s*ec(es, (hodopila globiformis Acidithiobacillus ferroo$idans,Picrophilus oshimae, etc.@.:he %*%*,*, m(croor)an(sms )roB o*t(mall" abo#e *0 ;.8 ?e.). Bacillus firmus, $rea!%e)ra%(n) bacter(a, %en(tr(f"(n) bacter(a@ ?:able ..@.

:able ..A ro$*(n) of m(croor)an(sms base% on the(r *0 tolerance?htt*ABBB.bmeorn"esz.h$sClatm%l.*h*%(rTs(loJF1.GfJ>J'6lJ>J'6#JF/(rob(olJ>J=)(aJF\aT%l\(%T77;\fTs(lo1.J8fJ>J'6lJ>J'6#/(rob(olJ>J=)(ael

o+e)"zet-.*%f.@

G6$ > ",'6' E&%'*#

A,+,*, [ 7.7 *0 lact(c ac(% bacter(a, acet(c ac(% bacter(a, some f$n)(

N#6",*, 7.7!;.8 most bacter(a A*%*,*, ] ;.8 *0 $rea!%e)ra%(n) bacter(a, %en(tr(f"(n) bacter(a

:able ..1 shoBs that, the *0 of some foo%s ?e.). #(ne)ar, soft %r(ns, fr$(t +$(ces, an% B(nes@ (sbeloB the *o(nt at Bh(ch bacter(a can )roB. e can also see that, *0 (s abo$t 7.4 an% abo#e (ncase of meats an% seafoo%s, Bh(ch maes these *ro%$cts s$sce*t(ble to s*o(la)e.

:able ..1A '**ro3(mate *0 #al$es of some foo%s ?=(ro, -66 Va" et al., 887,BBB.mt.n"me.h$ f̂oo%(nt!h$m(rose)e%lete...eloa%as.**t@

F+ > 7%*6#

Y(ne)ar, lemon +$(ce .Soft %r(ns .8!.8

Fr$(t +$(ces ?cherr"@ .9

(ne .;!1.8

Sa$erra$t .-!.9

So$r cherr" .1

'**les, a**le +$(ce, oran)e +$(ce, )ra*e, *l$m .8!1.7

:omatoes .;!1.

o)$rt .;!1.7

>$r%le% m(l 1.1!1.7

Soft cheese 1.7=eer 1.8!7.8

>offee 7.8

:ea 7.7

Fresh raB meat 7.9!4.

>anne% #e)etable 7.1!4.7

Po$ltr" meat 4,!4,9

Fresh raB m(l 4.1!4.;

F(sh 4.4!4.;


16/109

.. 2ZID':I25–:I25 P2:E5:I'L

B%$, +#,!,",!$


17/109

:he 5ernst eC$at(on e3*resses the re%o3 *otent(al, Bh(ch (s a re#ers(ble o3(%at(on!re%$ct(onrelat(onA

Eh T E8H G


18/109

to !88 mY, beca$se (t reacts rea%(l" B(th o3")en. It can acc$m$late onl" (n anaerob(cen#(ronments.

:he %ecl(ne (n re%o3 *otent(al as a res$lt of m(crob(al act(#(t" ?)roBth an% *ro%$ct(on ofre%$c(n) com*o$n%s@ (s the bas(s of some ra*(% tests.


19/109

:able ..A

heeses !8 – !88 7.8 – 7.4

heat ?Bhole )ra(n@ !8 – !48 4.8

Potato t$ber !-78 4.8

S*(nach, s*(nach +$(ce G91 4.

/(l G88 – G18 4.1 – 4.;

Pear, *ear +$(ce G14 1.

ra*e, )ra*e +$(ce G186 .6

Lemon, lemon +$(ce G; .

.1. 5U:25:E5:

L(e h$mans, m(croor)an(sms can $se foo%s as a so$rce of n$tr(ents an% ener)".Foo% (s necessar" for them beca$se of the folloB(n) reasonsA

• beca$se of the chem(cal elements, Bh(ch const(t$te m(crob(al b(omass,• molec$les Bh(ch essent(al for )roBth an% the" are $nable to s"nthes(ze,• s$bstrates that can be $se% as an ener)" so$rce.

/(crob(al )roBth nee%s the folloB(n)A

• Bater,• so$rce of ener)",• so$rce of n(tro)en,• #(tam(ns an% relate% )roBth factors,• m(nerals.

:a(n) acco$nt of the reC$(rements l(ste% abo#e, mo$l%s ha#e the loBest reC$(rement, folloBe%b" ram!ne)at(#e bacter(a, "easts, an% ram!*os(t(#e bacter(a.In case of foo%borne m(croor)an(sms, the most common so$rces of ener)" are s$)ars, alcohols,an% am(no ac(%s. Some m(croor)an(sms can also $t(l(ze com*le3 carboh"%rates ?e.). starches

an% cell$lose@ as so$rces of ener)". 2nl" a feB m(croor)an(sms can $se fats as so$rces of ener)".' lar)e n$mber of n(tro)eno$s com*o$n%s can be $se% as n(tro)en so$rces b" m(croor)an(sms.:he *r(mar" n(tro)en so$rces of m(croor)an(sms are am(no ac(%s. =$t some m(croor)an(sms can$t(l(ze free am(no ac(%s, *e*t(%es, *rote(ns, an% n$cleot(%es.roBth factors are or)an(c s$bstances, Bh(ch are necessar(l" nee%e% to the )roBth ofm(croor)an(sms. :he" are $nable to *ro%$ce them, so the" m$st *(c $* them from theen#(ronment.:he )roBth factors ma" be chem(call" class(f(e% (n the folloB(n) )ro$*sA

• am(no ac(%s ?e.). #al(ne an% )l$tam(c ac(% for lactobac(ll(@• #(tam(ns ?e.). for stre*tococc( an% lactobac(ll(@

•

branche%!cha(n fatt" ac(%s ?for r$men bacter(a@• cholesterol ?for m"co*lasma@.


20/109

/ost of the m(croor)an(sms reC$(re = #(tam(ns (n loB C$ant(t(es. ram!ne)at(#e bacter(a an%mo$l%s can s"nthes(ze = #(tam(ns most of the(r reC$(rements. =$t ram!*os(t(#e bacter(a arenee%e% to s$**l" B(th one or more = #(tam(ns.

.7. S'LI5I:

:he salt concentrat(on (s closel" relate% to Bater act(#(t", b$t (t (s %(sc$sse% se*aratel" beca$seof s*ec(al s()n(f(cance.0()h salt concentrat(on (s s*ec(al case of the loB Bater act(#(t"./ost of the *atho)en(c m(croor)an(sms )roB o*t(mall" $n%er -!J 5a>l concentrat(on.' h()her salt concentrat(on has s*ec(f(call" (nh(b(tor" effect.9.7J 5a>l concentrat(on (s the $**er l(m(t of most bacter(a )roBth.:hose m(croor)an(sms, Bh(ch are able to )roB $n%er 5a>l concentrat(on from 9.7 to -7J, calle%halotolerant ?salt!tolerant@. :he" are able to )roB (n the absence of salt an% also (n the *resence

of relat(#el" h()h salt concentrat(on. 'n e3am*le for salt!tolerant "easts (s ebaryomyceshansenii. :h(s )ro$* also (ncl$%es some *atho)ens s$ch as Staphylococcus aureus an% Bacilluscereus./(croor)an(sms, Bh(ch are able to )roB abo#e -7J 5a>l concentrat(on calle% halo*h(les ?saltlo#ers@, s$ch as Actinopolyspora halophila. 'mon) them, from a foo% h")(ene as*ect, *ibrio

parahaemolyticus has o$tstan%(n) (m*ortance. *2 parahaemolyticus ma" ca$se foo% *o(son(n)ma(nl" thro$)h the cons$m*t(on of raB, salte% seafoo%.

.4. P0SI>'L '5D =I2L2I>'L S::U


21/109

E&",!$, %%'#"#$

:he e3tr(ns(c *arameters are not s$bstrate %e*en%ent. :hese *arameters are re*resentat(#e ofthe stora)e en#(ronment. :hese *ro*ert(es ha#e effect on the foo%s an% as Bell as on the(rm(croor)an(sms. :hese *arameters are tem*erat$re of stora)e, osmot(c *ress$re, relat(#e

h$m(%(t" of en#(ronment, *resence an% concentrat(on of )ases, as Bell as *rocess(n) an%*reser#(n) o*erat(ons.

.9. :E/PE


22/109

M#$,*#$A the(r o*t(m$m tem*erat$re (s betBeen 7◦> an% 18◦>. :he" ca$se ra*(% s*o(la)e offoo%s store% at room tem*erat$re. :he(r or()(n (s freC$entl" h$man or an(mal. :he mostcommon meso*h(l(c foo%borne *atho)ens areA Salmonella, Staphylococcus aureus an%Clostridium perfringens.T#'"$A the(r o*t(m$m tem*erat$re (s betBeen 18◦> an% 17◦>. :he most common

thermotro*hs are thermotolerant col(forms, salmonellas an% cam*"lobacters.T#',*#$A the(r o*t(m$m tem*erat$re (s betBeen 78◦> an% ;8◦>.:he most (m*ortant re*resentat(#es of thermo*h(les are thermo*h(l(c lact(c ac(% bacter(a ?e.).Streptococcus salivarius s$bs*. thermophilus@ an% the en%os*ore form(n) Bacillus an%Clostridium )en$s.2ther thermo*h(l(c bacter(a )enera, Bh(ch ha#e (m*ortance (n foo%s, are Alicyclobacillus,!eobacillus, Paenibacillus, an% )hermoanaerobacter .:hermof(l(c bacter(a ?*art(c$larl" s*ore formers@ ha#e cons(%erable (m*ortance (n the cann(n)(n%$str".

.;. 2S/2:I> P


23/109

:able .;.-A :he relat(onsh(* betBeen the E

@ O$'", #$$6# 3%

2smo*h(l(c 48 798

47 741

98 144Zero*h(l(c 97 99

;8 6

Zerotolerant ;7 -

68 -;

0"%ro*h(l(c 67 49

-88 8

:he osmot(c *ress$re of foo% can be (ncrease% b" re%$c(n) the Bater content.:he *art(al remo#al of Bater content calle% concentrat(on ?e.). tomato *$ree@, an% the com*leteremo#al (s calle% %es(ccat(on or %r"(n) ?e.). m(l *oB%er, e)) *oB%er@.

2n the bas(s of the react(on to the osmos(s, the folloB(n) )ro$*s can be se*arate%A

• 2smotolerantA the" s$r#(#e b$t not )roB (n h"*erton(c me%($m.• Fac$ltat(#e osmo*h(l(cA the(r ma3(m$m )roBth (s (n h"*oton(c me%($m, b$t the" can also

)roB (n h"*erton(c me%($m.• 2bl()ate osmo*h(l(cA the" )roB onl" (n h"*erton(c me%($m.

.6.


24/109

.-8. PE '5D >25>E5:2@ an% ozone ?2@. In case of mo%(f(e% atmos*here *aca)e% ?/'P@ foo%s carbon %(o3(%e?>2@ an% o3")en ?2@ are $se%.2zone ?2@ has ant(m(crob(al *ro*ert(es, b$t (t (s a stron) o3(%(z(n) a)ent. 2zone sho$l% not be$se% (n case of h()h!l(*(%!content foo%s, beca$se (t ca$ses ranc(%(t" of them.

>arbon %(o3(%e ?>2@ (s most commonl" $se% (n mo%(f(e% atmos*here *aca)e% foo%s, (ncarbonate% m(neral Baters, carbonate% be#era)es, an% soft %r(ns. :he effect of >2 on m(crobes(s not $n(form.In )eneral, the ram!*os(t(#e bacter(a ?es*ec(all" lactobac(ll(@ are the most res(stant hoBe#erthe o3(%at(#e ram!ne)at(#e bacter(a an% mo$l%s are the most sens(t(#e.roBth (nh(b(t(on of carbon %(o3(%e (s $s$all" )reater $n%er aerob(c con%(t(ons, an% loBtem*erat$re.

.--. PESSI5 '5D P


25/109

5. FOODBORNE DISEASES

:he %ef(n(t(on of foo%borne %(sease b" the orl% 0ealth 2r)an(zat(on ?02@A M'n" %(sease of an(nfect(o$s or to3(c nat$re ca$se% b", or tho$)ht to be ca$se% b", the cons$m*t(on of foo% orBater&. :he %ef(n(t(on (ncl$%es not onl" %(seases B(th the enter(c s"m*toms ?%(arrhoea an%or#om(t(n)@, b$t also other s"m*toms, l(e those ca$se% b" to3(c chem(cals, moreo#er bot$l(sman% l(ster(os(s. In s*(te of the )eneral re)ar%s, m(crob(al hazar%s st(ll ha#e the h()hest *r(or(t" ofbecom(n) (ll connecte% to foo% cons$m*t(on.

Se#eral m(crob(al %(seases ma" be or()(nate% from foo%s, b$t onl" some of them contracte%e3cl$s(#el" ?e.). hemorrha)(c col(t(s an% l(ster(os(s@. 2thers, l(e bot$l(sm an% sta*h"lococcalfoo% *o(son(n) are *re%om(nantl" from the cons$m*t(on of foo% *ro%$cts. Some of the*re#(o$sl" (m*ortant foo%borne %(seases l(e anthra3 an% br$cellos(s rarel" (f e#er contracte%#(a the foo%borne ro$te noBa%a"s.

Foo%borne *atho)ens (ncl$%e the folloB(n) most (m*ortant )ro$*s an% ta3aAP"%

!iardia-ntamoeba)o$oplasmaSarcocystisCryptosporiumCyclospora

F6!,'("&,! +6#$ Aspergillus

1usariumPenicillium

Alternaria M6*",#**6*% %!,'%* %%$,"#$F*%"'$

Fl$es1asciola1asciolopsisParagonimusClonorchis

:a*eBormsiphyllobothrium)aenia

R6!+'$)richinella

Ascaris Anisa%isPseudoterranova)o$ocara

B%"#,%ram!*os(t(#e

StaphylococcusBacillus cereusB2 anthracisClostridium botulinum,C2 argentinensisC2 perfringensListeria monocytogenes

Mycobacterium avium subsp2 paratuberculosis

ram!ne)at(#eSalmonellaShigella-scherichia3ersinia*ibrioCampylobacterBrucella

#ar(ant form@V,6$#$

0e*at(t(s '5oro#(r$ses ?5orBal, etc.@re$tzfel%t!Vaob %(sease ?neB T&,#!,P("*%!"!$

Paral"t(c shellf(sh *o(son>()$ato3(n


26/109

Foo%borne %(sease can onl" enter thro$)h the moth, an% m$st be (n)este%. 'll foo%borne a)entsma" be contracte% #(a the fecal–oral ro$te, e3ce*t for bot$l(nal to3(ns, the m"coto3(ns, an% the*h"to*lanton to3(ns, an% not so common for sta*h"lococcal foo% *o(son(n). 0oBe#er th(s ro$te(s the *r(mar" ro$te of (nfect(on for the foo%borne #(r$ses an% entero*atho)en(c *rotozoa an%bacter(a. :he fecal–oral ro$te means, foo%borne *atho)ens are transm(tte% from contam(nate%

feces e(ther #(a the f(n)ers or cloths of foo% han%lers ?beca$se of $nsat(sfactor" h")(en(ccon%(t(ons@, or b" (nsects, or from Bater ?F()$re .-@.

F,6# 5.1A :he fecal–oral ro$tes of transm(ss(on of foo%borne (ntest(nal *atho)ens?=ase% on Va" et al., 881@

FolloB(n) the enter of the m(crobes (nto the )astro!(ntest(nal tract, *atho)en m$st f$lf(l se#eralreC$(rements (n or%er to ca$se (llness. ?-@ F(rst of all (t m$st s$r#(#e the e3tremel" ac(%(cen#(ronment of the stomach. ?@ :hen colon(zat(on of the (ntest(nal Balls or attach (s necessar"for enabl(n) the m$lt(*l(cat(on of the *atho)ens. :he (ntest(nal m$cosa l(n(n) the (ntest(nale*(thel(al s$rface (s %efence b$t, Listeria monocytogenes, (s able to o#ercome the m$c$s barr(erb" remo#(n) m$c$s thro$)h the a(% of l(ster(ol"s(n 2 ?LL2@. Some *atho)ens *atho)en, s$ch asC2 perfringens, hoBe#er %oes not nee% to attach to the (ntest(nal t(ss$es. ?@ Intest(nal *atho)ensm$st %efen% themself a)a(nst host %efense mechan(sms (n the )$t assoc(ate% l"m*ho(% t(ss$e.?1@ :he harmless (ntest(nal m(crob(ota (s able to e3cl$%e *atho)ens. :hat means, *atho)ensm(crobes ha#e to be able to com*ete B(th the hetero)eneo$s an% lar)e m(crob(ota of the )$t,an% the the loB!2 en#(ronment )astro(ntest(nal tract. ?7@ F(nall", the or)an(sms nee% to be ableto e(ther elaborate to3(c *ro%$cts ?e.)., *ibrio cholerae@ or cross the e*(thel(al Ball an% enter*ha)oc"t(c or somat(c cells ?e.)., L2 [email protected](nal *atho)ens ha#e %(fferent s(te of act(on. &elicobacter (s the onl" bacter($m thatcolon(zes $"'% Balls, b$t (ts foo%borne or()(n has not been *ro#e%. S'%** ,!"#$",!# (scolon(ze% b" se#eral *atho)ensA #(r$ses ?'stro#(r$ses, 0e*at(t(s ',


27/109

?Bacillus cereus, Campylobacter 5e5uni, Clostridium perfringens, -scherichia coli – EPE> an% E:E>stra(ns , Listeria monocytogenes, nontyphoid Salmonellae, S2 )yphi, Shigellae, *ibrio cholera, *2

parahaemolyticus, 3ersiniae@, *rotozoa ?Cryptosporidium parvum, Cyclospora cayetanensis,!iardia lamblia, )o$oplasma gondii@ an% helm(nts ?:a*eBorms@. Se#eral *atho)ens can colonozethe *%# ,!"#$",!# as BellA Campylobacter, -scherichia coli – E0E> an% EPE> stra(ns , -ntamoeba

histolytica, Salmonella Enter(t(%(s, Shigella dysenteriae. L,7# can be colon(ze% b" l(#er fl$es,moreo#er Listeria monocytogenes an% #(r$ses ?foo%borne 0e*at(t(s ' an% E@. F(nall" )richinellaspiralis )roB an% enc"st (n $#*#"%* '6$*#$.

:he *atho)enes(s of the foo%borne *atho)ens (s #er" #ersat(le. :he helm(nths are contracte% b"(n)est(n) (nfecte% meat or f(sh. FolloB(n) the(r entr", the ma" *assa)e to %(fferent or)ans ?l(#er,seletal m$scles@ or rema(n (n the )astro(ntest(nal tract. :he foo%borne *rotozoa rema(n (n the)$t, B(th the notable e3ce*t(on of )o$oplasma gondii. It can cross the (ntest(ne, e#en the*lacental barr(er, res$lt(n) se#ere %ama)e to a fet$s. :he m"coto3(ns are (n)este% *reforme%,acc$m$late% (n %(fferent or)ans, or cell com*onents ?e.)., aflato3(ns attach to D5'@. :he

*atho)en(c mechan(sms of the foo%borne bacter(a are more com*le3.

ram!*os(t(#e *atho)ens *ro%$ce e3ocell$lar #(r$lence factors. For e3am*le, Staphylococcusaureus #(r$lent stra(ns are *ro%$ce a n$mber of e3oto3(c factors, b$t onl" enteroto3(n *ro%$c(n)stra(ns ca$se the )astroenter(t(s s"n%rome. 'lso *ro%$ce% e3oto3(ns are res*ons(ble for the%(seases ca$se% b" Clostridium botulinum, C2 perfringens, an% Bacillus cereus. 'ltho$)h Listeriamonocytogenes (s also a ram *os(t(#e bacter($m, (t has a %(fferent mechan(sm as a *atho)en.Y(r$lent stra(ns of L2 monocytogenes can breach the m$co$s barr(er an% enter e*(thel(al cell B(ththe hel* of %(fferent factors, l(e listeriolysin 6 ?LL2@. It (s an (ntracell$lar *atho)en.

:he *atho)enes(s an% #(r$lence *ro*ert(es of ram!ne)at(#e bacter(a are %(fferent an% more

com*le3 than for ram!*os(t(#e bacter(a.

S2 enterica sero#ars carr" *atho)en(c(t" (slan%s - an% ?SPI!-, SPI!@, conta(n(n) the ma+or(t" ofthe *atho)en(c(t" )enes. :hese )enes ma" be acC$(re% #(a hor(zontal transfer b"e3trachromosomal, mob(le )enet(c elements ?*lasm(%s or *ha)es@ betBeen the closel" relate%salmonellae, -2 coli an% sh()ellae. D(fferent factors *la" role (n the *atho)enes(s of these bacter(a.:he f(rst reC$(rement that an (ntest(nal (n#as(#e *atho)en m$st meet (s that of (ntest(nala%hes(on. /ob(le )enet(c elements *la"s role (n the transfer of a%herencea%hes(#e )enesbetBeen a#(r$lent an% #(r$lent stra(ns. F(mbr(ae enhance the bacter(al attachment to the(ntest(nal cells ?e.). f(mbr(al a%hes(ns (n the #(r$lent stra(ns of S2 enterica@. :he" ma" also

*ro%$ce %(fferent enteroto3(ns, $s$all" co%e% on e3trachromosomal elements. 2ne 3amle of thehor(zontal )ene transfer (s the E0E> stra(ns e#ol#e% from EPE> #(a acC$(s(t(on of *ha)e!enco%e%Sh()a to3(ns.


28/109

5.1. S AP!YL"C"CC#S A#$E#S AND STAP>YLOCOCCAL GASTROENTERITIS

S,#!",, *%$$,,%",!

Doma(nA ='>:E an% 17◦>,


29/109

B(th the o*t(m$m betBeen 7◦> an% 18◦>. :he heat res(stance ?D4 T 8–47 s, D9 T 1.- s@ of S2aureus (s e3ce*t(onal.:he o*t(m$m *0 for )roBth (s betBeen 4.8 an% 9.8. :he m(n(m$m *0 for )roBth (s 1.8, an% thema3(m$m *0 (s 6.;. :he *0 ran)e of the enteroto3(n *ro%$ct(on (s betBeen *0 1.7 an% 6.8, an%the o*t(m$m *0 (s betBeen 4.8 an% 9.8.

S2 aureus can Bell tolerate the h()h sal(n(t" an% loB Bater act(#(t" of me%(a. It can )roB Bell (nme%(a Bh(ch conta(n(n) 7–-8J 5a>l, an% some stra(ns can )roB (n 8J 5a>l. Sta*h"lococc( can)roB at loBer Bater act(#(t" ?m(n(m$m aB (s 8.;@ #al$es than an" other salt!lo#(n) ?non!halo*h(l@ bacter(a. :he m(n(m$m Bater act(#(t" of the enteroto3(n *ro%$ct(on (s 8.;4 ?:able.-.-@.

:able .-.-A Ecolo)(cal *arameters of )roBth an% enteroto3(n *ro%$ct(on of Staphylococcusaureus ?Lacza", 88;@

E*,%* %%'#"#$G" E!"#"&,! +6",!

R%!# O",'6' R%!# O",'6'

T#'#%"6# C 4!1; 7!9 -8!17 7!18

> 1.8!6.; 4.8!9.8 1.7!6.8 4.8!9.8

N%C* @ 8!8 8.7!1.8 8!8 8.7

?%"# %",7,"( 8.;!8.66 8.6;!8.66[ 8.;4!8.66[ 8.66[

R#+& "#!",%* 'V !88 ! G88[ G88[ ! G88[

2n the bas(s of the(r ab(l(t" to ferment )l$cose the" can be %(st(n)$(she% from the Micrococcus./a+or(t" of S2 aureus stra(ns are coa)$lase!*os(t(#e, so the" *ro%$ce coa)$lase enz"me, b$t someof them %o not *ro%$ce coa)$lase.

P%"#!,,"( Staphylococcus aureus

S2 aureus (s the most common h$man bacter(al *atho)en. :he %e)ree of *atho)en(c(t" (s%eterm(ne% b" the b(ochem(cal act(#(t(es of S2 aureus ?coa)$lase, hemol"s(s, D5ase, *hos*hatase,mann(tol fermentat(on an% )elat(n h"%rol"s(s@. S2 aureus ha#e man" #(r$lence factors, (ncl$%(n)*rote(n!, l(*(%!, carboh"%rate!, n$cle(c ac(%!%e)ra%(n) enz"mes, to3(ns, an% factors Bh(ch%estro" *ha)oc"tes. Patho)ens *ro%$ce *lasma clott(n) coa)$lase an% thermostable n$cleaseenz"mes.

C#**-%$$,%"#+ 7,6*#!# %"$A e.). ca*s$lar *ol"sacchar(%e, m(croca*s$les, m$c$s, te(cho(cac(%s, l(*ote(cho(c ac(%s, *rote(n ', s*ec(f(c a%hes(on *rote(ns ?f(br(no)en, f(br(n, f(bronect(n,thromb(n, colla)en@.

E&"%#**6*% !!"&, %"#!,,"( %"$ #!('#$A

• C%6*%$# ?free an% bo$n%@A (t (s a *rote(n enz"me Bh(ch enables the con#ers(on off(br(no)en to f(br(n ?clots bloo% *lasma@ an% form a *rotect(#e la"er aro$n% the cells, Bh(ch*rotects them from the *ha)oc"tos(s.

• >(%*6!,+%$#$ ?also noBn as s*rea%(n) factor@A the" are fam(l" of enz"mes that %e)ra%eh"al$ron(c ac(%. :he" %estro" t(ss$es, thereb" a(%(n) the s*rea% of bacter(a ?(n#as(on@.

• S"%(*,!%$# ?f(br(nol"s(n@A (t (s an am(no ac(% enz"me. It act(#ates *lasm(no)en, Bh(ch

(s an (nact(#e *rec$rsor of *lasm(n. hen *lasm(no)en becomes act(#ate% (t (s con#erte% to*lasm(n. Plasm(n (s a tr"*s(n!l(e ser(ne *rotease, Bh(ch %()est f(br(n clots. :h(s enz"me


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attacs an% (nact(#ates ?%(ssol#e@ f(br(n molec$les therefore (t hel*s the s*rea% of bacter(a?(n#as(on@.

• D#&(,3!6*#%$# ?D5ase@A (t (s an enz"me, Bh(ch catal"zes the h"%rol"t(c clea#a)e of*hos*ho%(ester l(na)es (n the D5' ?%e)ra%(n) D5'@.

• P$%"%$#A th(s enz"me remo#es a *hos*hate )ro$* from a *rote(n ?%e*hos*hor"lat(on@.•

L,%$#A (t hel*s to %()est l(*(%s.• B#"%-*%"%'%$#$A enz"mes Bh(ch *ro#(%e res(stance to g!Lactam ant(b(ot(cs ?e.).*en(c(ll(ns@, beca$se the" brea the str$ct$re of ant(b(ot(cs.

P(#!, "&,! $6#%!",#!$ PTSA$AS$*erant()ens are molec$les, Bh(ch are able to st(m$late a m$ch h()her *ercenta)e of : cellsthan con#ent(onal ant()ens.

• T&, $ $(!+'# "&,! ?:SS:!-@• S"%(*%* #!"#"&,!$ ?SEs@

! 7 class(cal t"*esA SE', SE=, SE>, SED an% SEE! 5eB t"*es an% enteroto3(n!l(e ?SEl@ to3(nsA SE, SE0, SEI, SE@• -#'*($,! ?b(com*onent@• J-#'*($,! ?i!to3(n@A (t has a B(%e s*ectr$m of c"tol"t(c act(#(t".• L#6,+,!$A the" are *ore form(n) c"toto3(ns, Bh(ch (ll le$oc"tes.

O6#!# Staphylococcus aureus

'mon) the non!s*ore!form(n) h$man *atho)en, S2 aureus (s one of the most res(stant. It (s ableto s$r#(#e for e3ten%e% *er(o%s (n a %r" state.In case of the h$man %(sease!ca$s(n) sta*h"lococc(, the ma(n reser#o(r (s the h$mans. /ost ofthe sta*h"lococc( are normal (nhab(tants of the o$ter re)(ons of the bo%". S2 aureus occ$rs mostfreC$entl" on the s(n of h()her *r(mates, an% (n the nasal tract of the h$mans ?8–78J ofhealth" (n%(#(%$als@. 0oBe#er (t (s also a h$man *atho)en.Peo*le can be carr(ers an% so$rces of transferr(n) bacter(a to other h$mans an% to foo%.D(ssem(nat(on can occ$r b" %(rect contact, (n%(rectl" b" s(n fra)ments, or thro$)h res*(rator"tract %ro*let n$cle(.S2 aureus (s commonl" fo$n% (n faeces an% occas(onall" from so(l, mar(ne an% fresh Bater, *lant

s$rfaces, %$st, an% a(r.


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/ost so$rces of sta*h"loccal foo% *o(son(n) are h$mans Bho can contam(nate foo% %$r(n)*re*arat(on, f$rthermore contam(nate% eC$(*ment ?e.). meat )r(n%ers, n(#es, stora)e $tens(ls,c$tt(n) blocs, saB bla%es etc.@ $se% (n foo% *rocess(n).'n(mals are also an (m*ortant so$rce of sta*h"loccal foo% *o(son(n). :he" are often h()hl"colon(ze% B(th sta*h"lococc(.

/ast(t(s (s a #er" ser(o$s an% common *roblem (n the %a(r" (n%$str". It (s an (nfect(o$s %(sease ofmammar" t(ss$e, Bh(ch often ca$se% b" S2 aureus. It (s one of the most costl" %(seases (n an(mala)r(c$lt$re, beca$se of the comb(ne% losses an% e3*enses assoc(ate% B(th the %(sease. or abo#e 48◦> $nt(l cons$me%.

FolloB(n) con%(t(ons most often assoc(ate% B(th foo% *o(son(n)A

• (na%eC$ate refr()erat(on• *re*ar(n) foo%s far (n a%#ance of *lanne% ser#(ce• (nfecte% *ersonsH *ract(c(n) *oor *ersonal h")(ene ?e.)., not Bash(n) e(ther han%s or

(nstr$ments *ro*erl"@• (na%eC$ate coo(n) or heat *rocess(n) of foo%

*rolon)e% $se of Barm(n) *lates ?at bacter(al )roBth tem*erat$res@ Bhen ser#(n) foo%s, a

*ract(ce that *romotes sta*h"lococcal )roBth an% sta*h"lococcal enteroto3(ns.


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5.2. L%SE$%A M"&"CY"GE&ES AND FOODBORNE LISTERIOSIS

S,#!",, *%$$,,%",!

Doma(nA ='>:Ehr(st(e–'t(ns–/$nch–Petersen@ test (s cons(%ere% b" man" to be the %ef(n(t(#etest for L2 monocytogenes.


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C%%"#,$",$ Listeria monocytogenes

L2 monocytogenes (s ram!*os(t(#e, non!s*ore!form(n), fac$ltat(#e anaerobe, o3(%ase!ne)at(#ean% catalase!*os(t(#e. :he cells are cocco(% to ro% sha*e% ?8.1–8.7 m, 8.7–.8 m@. If thebacter(a c$lt$re% at 8–7◦>, the" ha#e *er(tr(cho$s fla)ella an% a character(st(c t$mbl(n)

mot(l(t".L2 monocytogenes can )roB o#er a B(%e ran)e of tem*erat$re from 8–17◦> B(th an o*t(m$mbetBeen 8 an% 7◦>. :he )roBth of bacter($m (s e3tremel" sloB beloB 7◦>. L2 monocytogenes (s

*reser#e% or mo%eratel" (nact(#ate% $n%er 8j>.:he res(stant of bacter(a a)a(nst freez(n) (s one of the lar)est betBeen the foo%borne *atho)ens.L2 monocytogenesis can be (nact(#ate% b" e3*os$re to tem*erat$res abo#e 78j>.:he heat res(stance of L2 monocytogenes (s not so lar)e ?D48 T a feB m(n$tes, D98 T a feB secon%s.In case of contam(nate% m(l, the bacter($m cells (ns(%e the m(l le$oc"tes are *rotecte% fromheat./ost of the stra(ns are $nable to )roB at *0 #al$es beloB 7.4. :he *0 ran)e for the )roBth of L2

monocytogenes (s betBeen 7.4 an% 6.4. 0oBe#er, the bacter($m can (n(t(ate )roBth (n me%(a at*0 #al$es as loB as 1.1. L2 monocytogenes can s$r#(#e th(s loB *0 ?1.1@ #al$e, b$t (t (s $nable to)roB. :he (nc$bat(on tem*erat$re an% the t"*e of ac(% affect the )roBth at loB *0 #al$es.L2 monocytogenes )roBs o*t(mall" at Bater act(#(t" of 8.69. For most stra(ns, the m(n(m$m Bateract(#(t" for )roBth (s 8.68–8.6. L2 monocytogenes (s able to s$r#(#e for lon) *er(o%s at Bateract(#(t" #al$e of 8.;.:h(s bacter($m (s salt tolerant as Bell. It (s able to )roB (n -8–-J so%($m chlor(%e. :hebacter($m s$r#(#es for lon) *er(o%s at h()h salt concentrat(ons./ost of the *atho)en(c L2 monocytogenes stra(ns ca$se beta!hemol"s(s on bloo% a)ar, an%ferment rhamnose b$t not 3"lose.

L2 monocytogenes *ro%$ce l(ster(ol"s(n 2 ?LL2@ to3(n, Bh(ch (s a hemol"s(n. :h(s (s a #(r$lencefactor of the bacter($m. LL2 (s a non!enz"mat(c, cholesterol!%e*en%ent, th(ol!act(#ate%, c"tol"t(c,*ore!form(n) to3(n *rote(n. 'll stra(ns of L2 monocytogenes ?also some non!hemol"t(c@ *ro%$cel(ster(ol"s(n 2.

O6#!# Listeria monocytogenes

L2 monocytogenes (s *resent e#er"Bhere (n the en#(ronment. :he bacter(a can be fo$n% (n freshan% salt Bater, so(l, seBa)e sl$%)e, %eca"(n) #e)etat(on, s(la)e, f$rthermore (n the faeces of *()s,shee*, cattle, ch(cens, t$re"s an% %$cs.L(ster(ae )enerall" l(#e there, Bhere the )en$s Brochothri$ , lact(c ac(% bacter(a, an% somecor"neform bacter(a occ$r. /ost of the an(mal or *lant or()(n foo% *ro%$cts are conta(n(n) L2monocytogenes. :he bacter(a (s )enerall" fo$n% (n raB m(l, %a(r" *ro%$cts ?e.). soft $nr(*ene%an% s$rface!r(*ene% cheeses@, fresh an% frozen meat, franf$rters, %el(catessen meats ?e.).salam(, ham, corne% beef, braBn an% *até@, *o$ltr", smoe% f(sh, seafoo% *ro%$cts, f$rthermoreon fr$(ts an% #e)etable *ro%$cts ?F()$re [email protected] monocytogenes can )roB (n the refr()erate% store% rea%"!to!eat ?


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L(ster(ae can )roB (n the *resence of h()h h$m(%(t" an% n$tr(ents. L2 monocytogenes (s mostoften reco#ere% from mo(st areas s$ch as floor %ra(ns, con%ensate, sta)nant Bater, floors, an%res(%$es on *rocess(n) eC$(*ment.L2 monocytogenes can attach to #ar(o$s t"*es of s$rfaces (ncl$%(n) sta(nless steel, )lass, *last(c,an% r$bber an% form b(of(lms as has been %escr(be% (n meat an% %a(r" *rocess(n) en#(ronments.

:he bacter(a are able to s$r#(#e the han%!Bash(n).L2 monocytogenes can be fo$n% (n the faeces (n %(fferent h$man *o*$lat(ons B(tho$t s"m*toms?e.). health" *eo*le, *re)nant Bomen, *at(ents B(th )astroenter(t(s, sla$)hterho$se Borers,foo% han%lers, an% laborator" Borers. [email protected] monocytogenes can be fo$n% (n to 4J of fecal sam*les from health" *eo*le, Bhereasl(ster(os(s *at(ents often e3crete h()her n$mbers.

F()$re ..-A Pro*ort(on of s(n)le sam*les at *rocess(n) an% reta(l (n non!com*l(ance B(th EU L2

monocytogenes cr(ter(a (n 8-- an% 8- ?EFS' – E>D>, 8-1@


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L,$"#,$,$

L2 monocytogenes (s a fac$ltat(#e (ntracell$lar *atho)en ?s$ch as Brucella an% Mycobacterium@Bh(ch able to s$r#(#e an% *rol(ferate (n the cells of the monoc"te–macro*ha)e s"stem.L(ster(os(s (s ca$se% b" L2 monocytogenes. It has emer)e% as a ma+or foo%borne %(sease %$r(n)the *ast 8 "ears.L(ster(os(s (s not a t"*(cal foo%borne (llness. It has a ma+or *$bl(c health concern beca$se of thefolloB(n) reasonsA! ser(o$sness of the %(sease ?men(n)(t(s, s*ontaneo$s abort(on, an% se*t(cem(a@,! h()h mortal(t" rate ?abo$t 8–8J@, an%! lon) (nc$bat(on *er(o% ?$* to ;8 %a"s@.:he $s$al (nc$bat(on *er(o% (s a feB Bees, b$t (t can #ar" betBeen - an% 68 %a"s.:h(s maes (t %(ff(c$lt to e3*lore the ca$ses of the %(sease.

' seasonal *attern Bas obser#e% (n the l(ster(os(s cases re*orte% (n the EU (n the *er(o% 88;an% 8-. :here Bas a stat(st(call" (ncreas(n) tren% o#er th(s *er(o%, tho$)h onl" sloBl"(ncreas(n) ?F()$re ..@. :he n$mber of conf(rme% cases of h$man l(ster(os(s (n 8- Bas -41,Bh(ch means a -8.7J (ncrease o#er the *re#(o$s "ear.

F()$re ..A :ren% (n re*orte% conf(rme% cases of h$man l(ster(os(s (n the EU betBeen 88; an%

8- ?EFS' – E>D>, 8-1@

>ontrol of L2 monocytogenes (n foo%s re*resents a s()n(f(cantl" )reater challen)e than mostfoo%borne *atho)ens.:he reasons are the folloB(n)A! th(s bacter($m (s B(%el" %(str(b$te% (n the en#(ronment,! (t (s res(stant to %(#erse en#(ronmental con%(t(ons ?e.). loB *0, h()h 5a>l concentrat(ons@,! (t (s fac$ltat(#el" anaerob(c,! (t (s *s"chrotro*h(c.

:he folloB(n) reasons shoB Bh" th(s bacter($m has ma+or concern (n the a)r(!foo% (n%$str"A! there are #ar(o$s Ba"s L2 monocytogenes can enter foo% *rocess(n) *lants,


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! (ts ab(l(t" for *rolon)e% s$r#(#al (n the en#(ronment ?so(l, *lants, an% Bater@, on foo%s, an% (nfoo% *rocess(n) *lants,! (ts ab(l(t" to )roB at loB tem*erat$res ? to 1j>@,! (t can s$r#(#e (n b(of(lms, f$rthermore on foo%s an% foo% contact s$rfaces for a lon) t(me $n%er$nfa#o$rable con%(t(ons.

L(ster(os(s (s more common (n (n%(#(%$als, Bh(ch are e3*ose% to a )reater r(s ?s$ch as *re)nantBomen, neonates, (mm$nocom*rom(se% a%$lts, an% the el%erl"@.In 8-, the h()hest not(f(cat(on rates of l(ster(os(s Bere re*orte% (n *ersons a)e% beloB one an%those a)e% 47 "ears an% abo#e. In the latter )ro$*, the rates (ncrease% b" a)e./a+or %(fferences (n not(f(cat(on rates Bere also obser#e% (n terms of )en%er. Female cases%om(nate% (n the a)e )ro$*s -7!1 an% 7!11 "ears an% 9-. J of these cases Bere relate% to*re)nanc". 0()her (nc(%ence rates Bere obser#e% (n male cases com*are% to female cases (n alla)e )ro$*s abo#e 17 "ears. In these a)e )ro$*s, the male!to!female rate rat(o (ncrease% b" a)e.In the ol%est a)e )ro$* ?;7 "ears or abo#e@ the male!to!female rate rat(o Bas -.9 ?F()$re ..@.

F()$re ..A 5ot(f(cat(on rates of h$man l(ster(os(s b" a)e an% )en%er (n the EU (n 8- ?EFS' –E>D>, 8-1@

S"m*toms of the %(sease can #ar" from a m(l%, fl$!l(e (llness to men(n)(t(s an%men(n)oence*hal(t(s. In case of *re)nant Bomen, the most common s"m*toms of the (nfl$enza!l(e (llness are the fe#er, hea%ache an% somet(mes )astro(ntest(nal s"m*toms.D$r(n) (nfect(on trans*lacental foetal (nfect(on ma" occ$r, Bh(ch ma" ca$se abort(on, st(llb(rth,or *remat$re labo$r.L(ster(os(s (n the neonates can be an earl"!onset s"n%rome ?occ$r at b(rth or shortl" later@ or alate!onset s"n%rome ?occ$r se#eral %a"s or Bees after b(rth@.:he earl" onset s"n%rome can be ca$se% b" (ntra$ter(ne (nfect(on. /ost common s"n%romes arethe se*s(s, *ne$mon(a, an% )ran$lomas. S"n%romes of late!onset s"n%rome are men(n)(t(s an%

se*s(s.


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:he health" *eo*le are #er" res(stant to (nfect(on ca$se% b" L2 monocytogenes. S"n%romes ofl(ster(os(s (n case of non!*re)nant a%$lts are se*t(cem(a, men(n)(t(s, men(n)oence*hal(t(s,febr(le )astroenter(t(s, an% en%ocar%(t(s. :he mortal(t" rate of en%ocar%(t(s (s abo$t 8–8J.:he )astro(ntest(nal l(ster(os(s (nfect(on reC$(res h()h %ose ?-87–-86 cf$)@ of L2 monocytogenes./ost cases of h$man %(sease ca$se% b" L2 monocytogenes occ$r s*ora%(call".

2nl" three ?-a, -b, an% 1b@ of the fo$rteen noBn sero#ars of L2 monocytogenes, acco$nt formore than 68J of h$man an% an(mal cases of l(ster(os(s.


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5.5. FOOD POISONING C AUSED BY GRAM-POSITIVE SPORE-FORMING

:he tBo most (m*ortant )enera of )ram!*os(t(#e bacter(a are Bacillus an% Clostridium. Bacillus s*ec(es are aerob(c. >lostr(%(a hoBe#er lac res*(rator" cha(n. :he" obta(n ener)" ?':P@ onl" b"s$bstrate!le#el *hos*hor"lat(on ?fermentat(on@. :he" are fo$n% (n nat$re *r(mar(l" (n so(l,Bhere l(#(n) as sa*ro*h"t(c so(l or)an(sms an% (nfect an(mals onl" (nc(%entall". Foo%borne%(seases ca$se% b" ram!*os(t(#e s*ore!form(n) ro%s are %$e to the(r e3oto3(n *ro%$ct(on.:here are at least three (m*ortant foo%borne *atho)en s*ec(esA Clostridium perfringens, C2botulinum, an% Bacillus cereus. ' *otent ne$roto3(n (s res*ons(ble for the s"m*toms (n bot$l(sm,Bh(ch (s *ro%$ce% b" cells )roB(n) (n s$sce*t(ble foo%s. :he C2 perfringens enteroto3(n (s*ro%$ce% %$r(n) s*or$lat(on of bacter(al cells (n the )astro(ntest(nal tract. B2 cereus ma" ca$setBo t"*es of foo%!assoc(ate% (llness. :he emet(c %(sease (s a foo% (nto3(cat(on, b$t the %(arrhoeals"n%rome of (s an (nfect(on ca$se% b" (n)este% #e)etat(#e cells or s*ores. :he (nc(%ence of foo%*o(son(n) ca$se% b" each of these or)an(sms (s relate% to certa(n s*ec(f(c foo%s.

727282 B AC9LL:S C-(-:S !AS)(6-;)-(9)9S

:a3onom"

Doma(nA =acter(aPh"l$mA F(rm(c$tes>lassA =ac(ll(2r%erA =ac(llalesFam(l"A Bacillaceae en$sA Bacillus

S*ec(esA B2 cereus :he kB2 cereus )ro$*H conta(ns s(3 )enet(call" h()hl" s(m(lar s*ec(esA B2 cereus sensu stricto, B2anthracis, Bacillus thuringiensis, Bacillus mycoides, Bacillus pseudomycoides an% Bacillus/eihenstephanensis.

Bacillus cereus (s a fac$ltat(#el" anaerob(c, ram!*os(t(#e, ro%!sha*e% bacter($m ?bac(ll$s meanssmall ro%@ B(th -.8–-. m %(ameter an% .8–7.8 m len)th. Its )re"(sh colon(es are lar)e ?–;mm %(ameter@, rather flat, often B(th (rre)$lar bor%ers ?cere$s means Ba3!l(e@. It (s able to)roB on common a)ar me%(a, an% the colon(es are s$rro$n%e% b" g!haemol"s(s zones on bloo%a)ar. Its ell(*so(%al en%os*ores are central (n the cell an% %o not ca$se sBell(n) ?F(). ..-.-@.


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F,6# 5.5.1.1= Bacillus cereus cell mor*holo)" ?left@ an% colon" mor*holo)" ?r()ht@ oncommom a)ra me%($m an% on bloo% s$rro$n%e% b" g!haemol"s(s zones a)ar

?So$rceA htt*ABBB.**%(ct(onar".combacter(a)*baccere$s.htm ?Patho)en Prof(le D(ct(onar"@, %oBnloa% t(meA-1.-.8-1.@

It (s $b(C$(to$s an% normall" *resent (n so(l, %$st, Bater, an% #e)etat(on moreo#er (t (s also acommon com*onent of the trans(ent )$t flora (n h$mans. It cannot tolerate loB *0 ?[ 7.8@, orBater act(#(t". B2 cereus sensu stricto (s meso*h(l(c, )roB(n) betBeen -8 an% 78 ◦>. :he*s"chrotolerant B2 cereus stra(ns Bere se*arate% an% %escr(be% as =2 /eihenstephanensis. :h(ss*ec(es (s character(ze% b" the ab(l(t" to )roB beloB 9 ◦> b$t not at 1 ◦>, an% also has s*ec(al)enet(c character(st(cs. B2 anthracis, B2 cereus an% B2 thuringiensis )enet(call" are closel" relate%.

:he %(st(n)$(sh(n) feat$res betBeen the s*ec(es are enco%e% b" )enes locate% on the h()hl"mob(le )enet(c elements ?*lasm(%s@.

Bacillus cereus can be (solate% from %(fferent foo%s an% foo% (n)re%(entsA r(ce, %a(r" *ro%$cts,s*(ces, %r(e% foo%s an% #e)etables. >ross!contam(nat(on can %(str(b$te s*ores or cells to otherfoo%s, l(e meat *ro%$cts. B2 cereus s*ores can a%here to the s$rfaces, moreo#er able to formb(of(lms. It ma" ca$se h")(en(c *roblem (n foo% (n%$str" eC$(*ment, as the b(of(lm *rotectss*ores an% #e)etat(#e cells a)a(nst (nact(#at(on b" san(t(zers. It (s freC$entl" (solate% from %a(r"*ro%$cts an% l()htl" heat!treate% foo%s B(th e3ten%e% refr()erate% stora)e, b$t an" foo% B(th*0]1.; *ossess a r(s of foo% s*o(la)e or foo%borne %(sease b" B2 cereus.

'n earl" re*ort assoc(at(n) foo% *o(son(n) B(th Bacillus s**. (n -684, Bhen s*ore form(n)aerob(c bac(ll$s Bas (solate% from meatballs (n a sanator($m Bhere 88 *eo*le %e#elo*e%s"m*toms of *rof$se %(arrhoea, stomach cram*s an% #om(t(n). :he f(rst %escr(be% foo%*o(son(n) b" B2 cereus Bas %escr(be% (n hos*(tals (n 5orBa" (n -619–-616.

:Bo %(st(nct foo%borne %(sease t"*es are assoc(ate% B(th B2 cereusA emet(c an% %(arrhoeal, an%both s"n%romes are ca$se% b" enteroto3(ns ?:able ..-.-@.

:he %(arrhoeal s"n%rome of B2 cereus (s an (nfect(on ca$se% b" #e)etat(#e cells, (n)este% as #(ablecells or s*ores. :he onset of s"m*toms of the %(arrhoeal s"n%rome (s abo$t ;–-4 h after

cons$m*t(on of the foo%, lasts for betBeen - an% 1 h, an% (s character(ze% b" ab%om(nal *a(n,*rof$se Bater" %(arrhoea an% rectal tenesm$s. 5a$sea an% #om(t(n) are less freC$ent.


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Ye)etat(#e cells of the bacter($m are *ro%$c(n) heat sens(t(#e *rote(n enteroto3(ns (n the small(ntest(ne (n the late e3*onent(alearl" stat(onar" *hase of )roBth. :he to3(ns are also sens(t(#eto *roteol"t(c enz"mes, l(e tr"*s(n an% *e*s(n. :hree *ore!form(n) c"toto3(ns are c$rrentl"assoc(ate% B(th %(arrhoeal %(seaseA haemol"s(n =L ?0bl@, nonhaemol"t(c enteroto3(n ?5he@ an%c"toto3(n K ?>"tK@. :he 0bl an% the non!haemol"t(c 5he are cons(st(n) of three *rote(ns, Bh(le

>"tK has onl" one com*onent. Some stra(ns *ro%$ce both 0=L an% 50E tho$)h others conta(nthe )enes for onl" one.

T%3*# 5.5.1.1A >haracter(st(cs of the tBo t"*es of =ac(ll$s cere$s foo%borne %(sease?'%a*te% from Stenfors 'rnesen et al., 88;@

C%%"#,$",$ D,%#%* +,$#%$# E'#", +,$#%$#

:"*e of to3(n Prote(n enteroto3(n?s@A 0bl, 5he, >"tK(m*l(cate%

>"cl(c *e*t(%eA emet(c to3(n?cere$l(%e@

Locat(on of to3(n

*ro%$ct(on

In the small (ntest(ne of the host Preforme% (n foo%s

Infect(#e %ose -87–-8; cf$ ?total@ l(#e cells are not reC$(re% for(nto3(cat(on

Inc$bat(on t(me ;–-4 h ?occas(onall" ̂ 1 h@ 8.7–4 h

D$rat(on of (llness -–1 h ?occas(onall" se#eral %a"s@ 4–1 h

S"m*toms 'b%om(nal *a(n, Bater" %(arrhoea an%occas(onall" na$sea. Lethal(t" hasocc$rre%.

5a$sea, #om(t(n) an% mala(se 'feB lethal cases ?*oss(bl" %$eto l(#er %ama)e@

Foo%s most

freC$entl"(m*l(cate%

Prote(naceo$s foo%s meat *ro%$cts,

so$*s, #e)etables, *$%%(n)s, sa$ces,m(l an% m(l *ro%$cts

Starch!r(ch foo%s Fr(e% an%

cooe% r(ce, *asta, *astr" an%noo%les

:he emet(c s"n%rome Bas f(rst (%ent(f(e% (n the earl" -698s. :h(s %(sease (s an (nto3(cat(onca$se% b" the emet(c to3(n, name% cere$l(%e. :he (nc$bat(on *er(o% (s betBeen 8.7 an% 4 ho$rs,an% the %$rat(on (s normall" 4–1 h. Yom(t(n) (s not accom*an(e% b" %(arrhoea. It can be se#eree#en lethal. >ere$l(%e, (s a -. Da c"cl(c c"cl(c %o%eca%e*s(*e*t(%e that (s ac(% an% heatres(stant. It (s *ro%$ce% b" a nonr(bosomal *e*t(%e s"nthetase, enco%e% b" the 1!b cere$l(%es"nthetase ?ces@ )ene cl$ster Bh(ch (s locate% on a me)a*lasm(% relate%. :he to3(n (s *ro%$ce%(n the foo% (n the late e3*onent(al to stat(onar" *hase of )roBth an% (s tho$)ht to act b" b(n%(n)

to an% st(m$lat(n) the #a)$s ner#e.

72722 C L6S)(99:M P-(1(9;!-;S 166 P69S6;9;!

:a3onom"

Doma(nA =acter(aPh"l$mA F(rm(c$tes>lassA >lostr(%(a2r%erA >lostr(%(alesFam(l"A Clostridiaceae

en$sA Clostridium S*ec(esA C2 perfringens


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Clostridium perfringens foo% *o(son(n) rans amon) the most common )astro(ntest(nal %(seases(n %e#elo*e% co$ntr(es.

C2 perfringens (s a ram!*os(t(#e, ro%!sha*e% anaerobe. :ho$)h a catalase!ne)at(#e anaerobe,b$t s$r#(#e an% occas(onall" )roB (n the *resence of o3")en. Its en%os*ores are o#al an%

s(t$ate% s$bterm(nal (n the cells. It %(ffers from most other clostr(%(a (n that the relat(#el" lar)ero%s ?- m %(ameter an% m len)th@ are enca*s$late% an% nonmot(le ?F(). ...-@.

F,6# 5.5.2.1= >olo$re% scann(n) electron m(cro)ra*h ?SE/@ *(ct$re of Clostridium perfringens en%os*ores ?left@ an% (ts colon(es on tr"*tose s$l*h(te c"closer(ne a)ar ?r()ht@.

?So$rceA htt*ABBB.me%(llsb.com(ma)esart(st(ma)es(ma)es44;4d-8;796.+*) ?/e%(cal Ill$strat(on So$rceboo@an% htt*ABBB.)rasss(cness.or).$B*!content$*loa%s8--8>*erfr(n)ens.+*) ?:he EC$(ne rass S(cness

F$n%@, %oBnloa% t(meA -1.-.8-1.@

C2 perfringens (s meso*h(l(c, )roB(n) o#er the tem*erat$re ran)e - to 78 ◦>, B(th o*t(m$m at1–19 ◦>. Its )roBth (s #er" sloB beloB 8 ◦>. :he )enerat(on t(me of C2 perfringens (s onl" 9.-

m(n at 1-◦

>. It has a *0 o*t(m$m of 4.8–9.7, an% #e)etat(#e cells cannot tolerate ac(%(cen#(ronment beloB *0 7. Its m(n(m$m aB for )roBth (s 8.67–8.69, b$t s*ore *ro%$ct(on a**earsto reC$(re h()her aB #al$es than the abo#e m(n(ma. roBth (s (nh(b(te% b" aro$n% 7J 5a>l. It (sheterofermentat(#e, an% a lar)e n$mber of carboh"%rates are attace%. :he m(croor)an(smreC$(res for - essent(al am(no ac(%s for )roBth. Foo% *o(son(n) as Bell as most other stra(ns ofC2 perfringens )roBs Bell on a #ar(et" of me%(a (f (nc$bate% $n%er anaerob(c con%(t(ons or (f*ro#(%e% B(th s$ff(c(ent re%$c(n) ca*ac(t". :he most commonl" em*lo"e% select(#e *lat(n)me%(a $se% to en$merate C2 perfringens em*lo" ant(b(ot(c?s@ as the select(#e a)ent an% s$lf(tere%$ct(on to *ro%$ce blac colon(es as the %(fferent(al react(on ?F(). ...-@.

:he en%os*ores of foo%!*o(son(n) stra(ns %(ffer (n the(r res(stance to heat. D(fferences (n heatsens(t(#(t" amon) C2 perfringens stra(ns are assoc(ate% B(th the carr(a)e of the cpe )ene. :hosestra(ns has h()her -88◦> #al$es ?] 18@ Bhere the cpe )ene (s chromosomal, Bh(le stra(ns cpe carr(e% on *lasm(%s has loBer -88◦> ?t"*(call"


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(n the )eneral *o*$lat(on, Bh(le the heat sens(t(#e t"*es are common (n the (ntest(nal tract of allh$mans. C2 perfringens )ets (nto meats %(rectl" from sla$)hter an(mals or b" the s$bseC$entcontam(nat(on of sla$)htere% meat from conta(ners, han%lers, or %$st. =eca$se (t (s a s*oreformer, (t can B(thstan% the a%#erse en#(ronmental con%(t(ons of %r"(n), heat(n), an% certa(nto3(c com*o$n%s.

:he s*ec(es (s class(f(e% (nto f(#e t"*es ?'–E@ base% on the *ro%$ct(on of fo$r ma+or e3oto3(ns ?,

g, , an% ι@. C2 perfringens t"*e ' Bh(ch (s res*ons(ble for foo% *o(son(n) an% )as )an)rene*ro%$ces onl" the a ma+or a to3(n Bh(ch has lec(th(nase ?*hos*hol(*ase >@ act(#(t". It (s a s*ore!s*ec(f(c *rote(n, be(n) (ts *ro%$ct(on occ$rs to)ether B(th that of s*or$lat(on. C2 perfringens foo%*o(son(n) (s character(ze% b" na$sea, ab%om(nal *a(n, %(arrhoea an%, less commonl" #om(t(n).:he (nc$bat(on *er(o% (s $s$all" ; to 1 h. >ons$m*t(on of foo% conta(n(n) lar)e n$mbers ofenteroto3(n *os(t(#e #e)etat(#e C2 perfringens cells ?]-87 )!-, alto)ether -84–-8; cf$@ arenecessar" for foo% *o(son(n). Foo% *o(son(n) %$e to t"*e ' stra(ns has been fatal onl" (n el%erl"or otherB(se %eb(l(tate% *ersons, Bh(le me%(cal treatment (s not $s$all" reC$(re% (n otherB(se

health" (n%(#(%$als, an% reco#er" (s com*lete B(th(n -– %a"s.

In)este% #e)etat(#e cells that s$r#(#e the stomachHs ac(%(t" *ass to the small (ntest(ne Bherethe" )roB an% s*or$late. :he enteroto3(n (s s"nthes(ze% b" the s*or$lat(n) cells, altho$)h loBle#els of *ro%$ct(on ha#e been obser#e% (n #e)etat(#e c$lt$res. :he to3(n (s closel" assoc(ate%B(th the s*ore coat, an% (s release% (nto the (ntest(nal l$men folloB(n) the l"s(s of thes*oran)($m. :he enteroto3(n (s a 7 Da *rote(n, an% can be (nact(#ate% b" heat(n) (n sal(ne at48 ◦> for -8 m(n an% (s sens(t(#e to some *roteol"t(c enz"mes. It re#erses the floB of 5aG, >l!, an%Bater across the )$t e*(thel($m b" from absor*t(on to secret(on, s(m(larl" to cholera to3(n. Itacts at the cell membrane b" b(n%(n) to s*ec(f(c *rote(n rece*tors then (nsert(n) (nto thee*(thel(al cell membrane, an% chan)(n) cell *ermeab(l(t", *ro%$ces *ores (n the membrane, an%(nh(b(t(n) s"nthes(s of macromolec$les. E*(thel(al cells e#ent$all" %(e as a res$lt of membrane%ama)e.

:he foo%s (n#ol#e% (n C2 perfringens o$tbreas are often meat %(shes *re*are% one %a" an% eatenthe ne3t, Bhen heat *re*arat(on (na%eC$ate to %estro" the heat!res(stant en%os*ores.En%os*ores ma" )erm(nate an% )roB %$r(n) the sloB cool(n) or *rolon)e% stora)e at roomtem*erat$re. 'cc$m$late% #e)etat(#e cells (s not %estro"e% (s foo% (s e(ther ser#e% col% orreheate% (ns$ff(c(entl" to (ll them. Some of the (n)este% cells s$r#(#e thro$)h (nto the small(ntest(ne Bhere the" s*or$late an% *ro%$ce enteroto3(n. >$re% meats are rarel" (n#ol#e% (n C2

perfringens foo% *o(son(n), beca$se salt content, n(tr(te le#el an% heat *rocess(n) effect(#el"

control )roBth of C2 perfringens (n comb(nat(on. /ost o$tbreas occ$r (n connect(on B(th(nst(t$t(onal cater(n) s$ch as schools, ol% *eo*leHs homes an% hos*(tals. :he folloB(n)*reca$t(ons Bo$l% hel* to *re#ent C2 perfringens foo% *o(son(n)sA ?(@ coo or roast meat $nt(l the(nternal breast tem*erat$re reaches at least 91◦>, ?((@ *re#ent cross!contam(nat(on of *re*are%

meat B(th *atho)ens from the raB one ?san(t(ze all conta(ners an% eC$(*ment that *re#(o$sl"ha% contact B(th raB, Bash han%s an% $se %(s*osable *last(c )lo#es@, ?(((@ ch(ll the *re*are%meat as ra*(%l" as *oss(ble after coo(n), ?(#@ heat store% meat at least 91◦> +$st *r(or to ser#(n).

Some t"*e > stra(ns *ro%$ce enteroto3(n an% ma" ca$se a foo%!*o(son(n) s"n%rome enter(t(snecrot(cans, a more se#ere ?B(th a mortal(t" rate of 7–18J@, b$t rare, enter(c %(sease. It (s

ca$se% b" C2 perfringens *ro%$ces an% g to3(ns. :he later one %ama)es the (ntest(nal m$cosaca$s(n) necros(s. Illness (s *re#entable b" act(#e (mm$n(zat(on a)a(nst the g to3(n. S"m*toms of


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ab%om(nal *a(n an% bloo%" %(arrhoea %e#elo* se#eral %a"s after a h()h!*rote(n meal. LoB le#elsof (ntest(nal *roteases are a *re%(s*os(n) factor (n #(ct(ms. 2$tbreas Bere re*orte% (n erman"(n -614 an% -616. 5oBa%a"s (t occ$rs ma(nl" (n Pa*$a 5eB $(nea folloB(n) fest(#e occas(ons,Bhen *or (s cons$me% B(th sBeet *otatoes, conta(n(n) *rotease (nh(b(tors.

727272 C L6S)(99:M B6):L9;:M 166 P69S6;9;! = B6):L9SM

:a3onom"

Doma(nA =acter(aPh"l$mA F(rm(c$tes>lassA >lostr(%(a2r%erA >lostr(%(alesFam(l"A Clostridiaceae en$sA Clostridium S*ec(esA C2 botulinum

=ot$l(sm (s a se#ere, often fatal, foo% *o(son(n). :he s"m*toms of bot$l(sm are ca$se% b" the(n)est(on of a h()hl" to3(c, sol$ble e3oto3(n *ro%$ce% b" the or)an(sm Bh(le )roB(n) (n foo%s. It(s the most *o(sono$s s$bstance noBn. In)est(n) e#en a small amo$nt of th(s ne$roto3(n can be%an)ero$s.

'mon) the earl(est references to h$man bot$l(sm Bas the or%er b" Em*eror Leo YI ?r$lers ofthe ="zant($m a% ;;4–6-@, forb(%%(n) the eat(n) of bloo% sa$sa)e beca$se of (ts harmf$l healtheffects. :he f(rst %oc$mente% Msa$sa)e *o(son(n)& B(th - cases an% 4 %eaths, occ$rre% (n -96(n (l%ba% ürttember), (n So$th estern erman". It Bas trace% to bloo% sa$sa)e ?*() )$t

f(lle% B(th bloo% an% other (n)re%(ents@. V$st(n($s Kerner, a local %(str(ct me%(cal off(cer (l%ba%ürttember) st$%(e% of the %(sease Bh(ch became noBn as Msa$sa)e *o(son(n)& or bot$l(sm?Lat(nA bot$l$sTsa$sa)e@. 0e has note%, that heat(n) Bas an essent(al *recon%(t(on for the%e#elo*ment of to3(c(t" (n sa$sa)es an% that small sa$sa)es or those conta(n(n) a(r *ocets Bereless l(el" to become to3(c.

F(nall" Em(le P(erre #an Ermen)em of the Un(#ers(t" of hent %(sco#ere% the bot$l(n$m to3(n!*ro%$c(n) bacter(a (n -;64, an% name% Bacillus botulinus (n -;64, Bhen he st$%(e% the o$tbrea(n a m$s(c cl$b or()(nate% from raB salte% ham, Bhen of the 1 members became (ll, an% %(e%. :he ca$sat(#e bacter($m Bas reclass(f(e% as Clostridium botulinum (n -6.

=ot$l(sm (s ca$se% b" certa(n stra(ns of C2 botulinum, Bh(ch (s ram!*os(t(#e, an% obl()atel"anaerob(c. :he cells are stra()ht or sl()htl" c$r#e% ro%s B(th –-8 m lon), an% form central ors$bterm(nal o#al s*ores. Ye)etat(#e cells are mot(le B(th *er(tr(cho$s fla)ella ?F(). ...-@.


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F,6# 5.5.5.1= /(crosco*(c ?left@ an% colo$re% SE/ ?r()ht@ *(ct$re of Clostridium botulinum ?So$rceA htt*ABBB.**%(ct(onar".combacter(a)*bacbot$l(n$m.+*) ?Patho)en Prof(le D(ct(onar"@ an%

htt*Acora3(t.comB*!content$*loa%s8-8;>lostr(%($m!bot$l(n$m!sem!483-.+*) ?5eo)ee@, %oBnloa%t(meA -1.-.8-1.@

2n the bas(s of the serolo)(cal s*ec(f(c(t" of the(r to3(ns, se#en t"*es are reco)n(ze%A ', =, >, D, E,

F, an% . :"*es ', =, E, F, an% ca$se %(sease (n h$mans t"*e > ca$ses bot$l(sm (n b(r%s, cattle,m(n, an% other an(mals an% t"*e D (s assoc(ate% B(th fora)e *o(son(n) of cattle, es*ec(all" (nSo$th 'fr(ca. :he t"*es are also %(fferent(ate% on the bas(s of the(r *roteol"t(c act(#(t". :"*es ', an% some t"*es = an% F are *roteol"t(c, Bh(le non*roteol"t(c stra(ns are >, D, E an% some =an% F stra(ns. :he *roteol"t(c act(#(t" of t"*e (s sloBer than that for t"*e ', an% (ts to3(nreC$(res tr"*s(n *otent(at(on. 'll stra(ns that *ro%$ce the :"*e to3(n are *lace% (n the s*ec(esC2 argentinense2 =ot$l(nal to3(n t"*e F has been %etecte% (n Clostridium baratii, an% a ne$roto3(nthat (s ant()en(call" s(m(lar b$t not (%ent(cal to t"*e E (s elaborate% b" Clostridium butyricum2

C2 botulinum (s has been %(#(%e% (nto fo$r )ro$*s, base% on *h"s(olo)(cal %(#ers(t" an%

conf(rme% b" molec$lar st$%(es base% on D5' homolo)" an% r(bosomal . ro$* IY or)an(sms are *roteol"t(c, *ro%$ce to3(n, an% )roB at 7 to 17◦>. 'll fo$r )ro$*s form s$bterm(nal ell(*so(%al s*ores. /ost cases of

bot$l(sm (n h$mans are %$e to to3(n t"*es ', = or E. ro$* III stra(ns *ro%$c(n) to3(n t"*es >an% D are $s$all" assoc(ate% B(th (llness (n an(mals an% b(r%s.

C2 botulinum (s essent(all" a so(l sa*ro*h"te an% (n%()eno$s to Baters too. It occ$rs B(%el",altho$)h the )eo)ra*h(cal %(str(b$t(on (s not $n(form. In E$ro*ean so(ls t"*e = ten%s to be more

common than t"*e ', Bh(ch (s the most common (n the estern States of US'. :he :"*e to3(n*ro%$c(n) C2 argentinense has been reco#ere% from so(ls (n 'r)ent(na, SB(tzerlan%, an% theUn(te% States. :he *s"chrotro*h(c t"*e E has been *art(c$larl" assoc(ate% aC$at(c m$%s (nre)(ons s$ch as Bestern 5orth 'mer(ca, Va*an an% the =alt(c Sea coasts. 's a conseC$ence, t"*eE (s often res*ons(ble for o$tbreas of bot$l(sm Bhere f(sh (s the #eh(cle. :he h$man mortal(t"rate (s $s$all" h()h ?8–78J@, an% t"*e ' to3(n $s$all" *ro%$ces a h()her mortal(t" than = or E.

:he m(n(m$m *0 at Bh(ch C2 botulinum B(ll )roB (s *0 aro$n% 1.9. 5on!*roteol"t(c stra(ns ha#ea loBer ac(% tolerance an% are )enerall" (nh(b(te% at *0 7.8–7., an% the ma3(m$m *0 for)roBth (s ;.7–;.6, moreo#er the to3(n (s $nstable at alal(ne *0 #al$es. It can be (nact(#ate% b"

heat(n) at ;8

◦

> for -8 m(n, or bo(l(n) tem*erat$res for a feB m(n$tes.


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S(3 t"*es of bot$l(sm are reco)n(ze%, from Bh(ch foo%borne bot$l(sm (s e3cl$s(#el" bo$n% tofoo%, an% (nfant ma" connecte% to foo%. Foo%borne bot$l(sm (s foo% *o(son(n), res$lt(n) fromthe (n)est(on of an e3oto3(n *ro%$ce% b" Clostridium botulinum )roB(n) (n the foo%. :hebot$l(n$m to3(ns are ne$roto3(ns. In)este% to3(n (s absorbe% (n the $**er *art of the small(ntest(ne an% reaches the bloo%stream. 'fter bot$l(nal to3(ns are absorbe% (nto the bloo%

stream, the" enter the *er(*heral ner#o$s s"stem. It b(n%s to the ner#e en%(n) at the ner#e–m$scle +$nct(on, bloc(n) release of the acet"lchol(ne res*ons(ble for transm(ss(on of st(m$l(,th$s *ro%$c(n) a flacc(% *aral"s(s ?F(). ...@.

F,6# 5.5.5.2= =loca%e of ne$rotransm(tter relases b" bot$l(n$m to3(n?So$rceA htt*ABBB.b(ocarta.com*athf(leshdbot$l(nPathBa".)(f ?=(ocarta@, %oBnloa% t(meA -1.-.8-1.@ ?@

:he bot$l(nal ne$roto3(ns ?=o5:@ are the most to3(c s$bstances noBn ?lethal %ose for an a%$lth$man (n the or%er of -8!; )@. :he" are h()h molec$lar mass ?-78 Da@ *rote(ns an% can are*ro%$ce% %$r(n) lo)ar(thm(c )roBth as com*le3es an% release% (nto the s$rro$n%(n) me%($mon cell a$tol"s(s.=o5: (s s"nthes(ze% as a s(n)le *ol"*e*t(%e cha(n that (s *osttranslat(onall" act(#ate% b"*roteol"t(c clea#a)e n(ce% to form a %(!cha(n cons(st(n) of a -88!Da hea#" cha(n an% a 78!Dal()ht cha(n hel% to)ether b" a %(s$lf(%e bon%. It (s com*ose% of three %oma(nsA b(n%(n),translocat(on, an% catal"t(c. Proto3(n can be act(#ate% b" the )$t enz"me tr"*s(n, or b" the


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*roteol"t(c to3(n (tself. :he hea#" cha(n ?-88 Da@ (s res*ons(ble for s*ec(f(c b(n%(n) to ne$ronalcells an% cell *enetrat(on. :he l()ht cha(n (s a z(nc en%o*e*t(%ase Bh(ch clea#es com*onents ofthe %oc(n) an% f$s(n) com*le3 of the s"na*t(c #es(cle, conta(n(n) the ne$rotransm(tteracet"lchol(ne ?F(). ...@.

In(t(al s"m*toms of bot$l(sm occ$r from ; h to ; %a"s, most commonl" -–1; h, aftercons$m*t(on of the to3(n!conta(n(n) foo%. S"m*toms (ncl$%e #om(t(n), const(*at(on, $r(neretent(on, %o$ble #(s(on, %(ff(c$lt" (n sBalloB(n), %r" mo$th an% %(ff(c$lt" (n s*ea(n). :he*ro)ress(#e Beaness f(nall" res$lts (n res*(rator" or heart fa(l$re (n fatal cases, -–9 %a"s afterthe onset of s"m*toms. S$r#(#al (s cr(t(call" %e*en%ent on earl" %(a)nos(s an% treatment,*r(nc(*all" b" alal(ne stomach Bash(n) to remo#e an" rema(n(n) to3(c foo%, (ntra#eno$sa%m(n(strat(on of s*ec(f(c or *ol"#alent ant(!to3(ns to ne$tral(ze c(rc$lat(n) to3(n, an%mechan(cal res*(rator" s$**ort Bhere necessar". S$r#(#(n) *at(ents ma" tae as lon) as ;months to reco#er f$ll".

Infant bot$l(sm Bas f(rst %escr(be% (n -694 an% (s most freC$entl" re*orte% (n the Un(te% States

(n the a)e of Bees to 4 months ?aro$n% the t(me that non!m(l fee%s are (ntro%$ce%@. It %(ffersfrom the class(cal s"n%rome (n that (t res$lts from colon(zat(on of the (nfantHs )$t B(th C2botulinum an% *ro%$ct(on of to3(n (n s(t$. 't th(s sta)e the (nfantHs )$t m(croflora (s not f$ll"%e#elo*e% an% (s less able to o$tcom*ete. Infants o#er one "ear of a)e ten% not to be affecte% b"th(s s"n%rome beca$se of the establ(shment of a more normal (ntest(nal b(ota. Infants )et #(ables*ores from (nfant foo%s an% *oss(bl" from the(r en#(ronment. Yeh(cle foo%s are those that %onot $n%er)o heat *rocess(n) to %estro" en%os*ores the tBo most common *ro%$cts are s"r$*an% hone".

:here are common feat$res are %(scern(ble (n o$tbreas of bot$l(smA ?-@ :he foo% has been

contam(nate% from so(l or m$% at so$rce or %$r(n) *rocess(n) B(th s*ores or #e)etat(#e cells ofC2 botulinum. ?@ :he foo% rece(#es some heat treatment that restr(cts the com*et(t(#em(croflora. ?@ >on%(t(ons (n the foo% ?tem*erat$re, *0, Eh, aB@ are s$(table for the )roBth of C2botulinum. ?1@ :he foo% (s cons$me% col% or after a m(l% heat treatment (ns$ff(c(ent to (nact(#ateto3(n. >ann(n) (n%$str" has to (ntro%$ce str(n)ent *rocess control to ens$re safet" of the loB!ac(% canne% foo%s, Bh(ch can f$lf(l all the abo#e cr(ter(a. :he )reatest hazar%s of bot$l(sm comefrom home!*re*are% an% home!canne% foo%s that are (m*ro*erl" han%le% or )(#en (ns$ff(c(entheat treatments to %estro" bot$l(nal s*ores. S$ch foo%s are often cons$me% B(tho$t heat(n).:he best *re#ent(#e meas$re (s the heat(n) of s$s*ect foo%s to bo(l(n) tem*erat$res for a feBm(n$tes, Bh(ch (s s$ff(c(ent to %estro" the ne$roto3(ns.


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5.4. S ALM"&ELLA GENUS AND FOODBORNE GASTROENTERITIS CAUSED BY S ALM"&ELLA

S,#!",, *%$$,,%",!

Doma(nA ='>:E


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:he most $sef$l techn(C$e for serot"*(n) salmonellae (s the Ka$ffmann–h(te scheme.It %escr(bes or)an(sms on the bas(s of the(r somat(c ?2@, fla)ellar ?0@, an% ca*s$lar*ol"sacchar(%e ?Y(@ ant()ens.Somat(c ant()ens are l(*o*ol"sacchar(%es ?LPS@, Bh(ch can be fo$n% on the e3ternal s$rface ofthe bacter(al o$ter membrane. :he heat!stable somat(c ant()ens are class(f(e% as ma+or or m(nor

ant()ens. Fla)ellar ant()ens are heat!lab(le *rote(ns, an% assoc(ate% B(th the *er(tr(cho$sfla)ella. >a*s$lar ant()ens, often occ$r (n the fam(l" -nterobacteriaceae, hoBe#er the Y( ant()en(s l(m(te% to the Salmonella )en$s. Y( ant()en occ$rs onl" (n S2 :"*h(, S2 Parat"*h( >, an% S2D$bl(n.In accor%ance to the 2 ant()ens, Salmonella s*ec(es an% sero#ars are %(#(%e% (nto )ro$*s ', =, >,an% so on. Fla)ellar ant()ens can be $se% for f$rther class(f(cat(on. :here tBo t"*es of fla)ellarAs*ec(f(c *hase ?*hase -@, an% )ro$* *hase ?*hase @. :he fla)ellar *hase (s more B(%el"%(str(b$te% amon) salmonellae, than *hase -.:he *hase - fla)ellar ant()ens are %es()nate% B(th small letters, an% *hase B(th arab(cn$merals. For e3am*le the -,1,7,-A(A-, sero#ar ?Salmonella :"*h(m$r($m@ means the

folloB(n)A 2 ant()ensA -, 1, 7 an% - 0 ant()ensA *hase-A ( *hase A - an% .Salmonella s$b)ro$*s are %ef(ne% as sero#ars.Des*(te the relat(#el" loB n$mber of 2, *hase -, an% *hase ant()ens, there are n$mero$s ?o#er788@ sero#ars.

Earl(er the salmonella sero#ars Bere treate% as s*ec(es, b$t noBa%a"s (t (s no lon)er $se%.For e3am*le, S2 typhimurium becomes S2 enterica s$bs*. enterica sero#ar :"*h(m$r($m, or moreconc(sel" Salmonella :"*h(m$r($m.:he sero#ars can be %es()nate% B(th ca*(tal(ze% an% not (tal(c(ze% folloB(n) the )en$s.

C%%"#,$",$ Salmonella #!6$

In )eneral, salmonellae are meso*h(l(c, b$t some Salmonella stra(ns are able to )roB also at h()htem*erat$res ?abo#e 71j>@, an% others can )roB (n foo%s store% at j> to 1j>. roBth has beenrecor%e% from tem*erat$res +$st abo#e 7◦> $* to 19◦> B(th an o*t(m$m at 9◦>. Salmonellas areheat sens(t(#e ?D48 T 8.-! m(n, D47,7 T 8.8!8. m(n@ an% are rea%(l" %estro"e% b" *aste$r(zat(ontem*erat$res.Salmonella s**. can )roB at *0 #al$es ran)(n) from 1.8 to 6.7 B(th an o*t(m$m *0 for )roBth of4.7 to 9.7.:he m(n(m$m Bater act(#(t" for )roBth (s aro$n% 8.6 b$t cells s$r#(#e Bell (n %r(e% foo%s, the

s$r#(#al rate (ncreas(n) as the Bater act(#(t" (s re%$ce%.Salmonellae cannot tolerate h()h salt concentrat(ons. 'ltho$)h Salmonella (s )enerall" (nh(b(te%(n the *resence of to 1J 5a>l, tolerance to salt can (ncrease B(th (ncreas(n) tem*erat$re (n theran)e of -8 to 8◦>. 't 8◦>, Salmonella can )roB sloBl" (n the *resence of 4J 5a>l. =r(ne abo#e

6J (s re*orte% to be bacter(c(%al.

In )eneral, salmonellae cannot ferment lactose ?B(th the e3ce*t(on of some sero#ars@ an%s$crose, b$t the" ferment )l$cose Bh(le *ro%$c(n) )as. Salmonellae )enerall" $t(l(ze am(no ac(%sas n(tro)en so$rces, b$t the sole n(tro)en so$rces of S . :"*h(m$r($m are n(trate, n(tr(te, an%ammon($m.


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O6#!# Salmonella #!6$

Salmonellae are B(%el" %(str(b$te% (n nat$re. :he *r(mar" reser#o(rs of salmonellae are h$mansan% an(mals.:he *r(mar" hab(tat of these bacter(a (s the (ntest(nal tract of an(mals ?e.). farm an(mals, b(r%s,re*t(les, an% (nsects@. 'ltho$)h the(r ma(n hab(tat (s the (ntest(nal tract, the" can also be fo$n% (nother *arts of the bo%". :he bacter(a can be transm(tte% from the faeces to se#eral *laces b"(nsects an% other or)an(sms. :he" also can be fo$n% (n *oll$te% Bater.hen *oll$te% Bater an% contam(nate% foo%s are cons$me% b" h$mans an% other an(mals,these or)an(sms are once a)a(n she% thro$)h faecal matter B(th a cont(n$at(on of the c"cle.' carr(er (s %ef(ne% as a *erson or an an(mal that re*eate%l" she%s Salmonella s**., $s$all"thro$)h faeces, B(tho$t shoB(n) an" s()ns or s"m*toms of the %(sease.

D,$#%$#$ %6$#+ 3( Salmonella #!6$

Salmonellae are the most (m*ortant ram!ne)at(#e ro%s, Bh(ch ma" ca$se foo%borne)astroenter(t(s.Salmonellae are res*ons(ble for se#eral %(fferent s"n%romes, s$ch as s"stem(c %(sease an%enter(t(s.

S($"#', D,$#%$#. 0ost!a%a*te% Salmonella serot"*es are more (n#as(#e an% the" are able toca$se s"stem(c %(sease (n the(r hosts. For e3am*le (n case of h$mans, the S . :"*h(, an% S .Parat"*h( ', =, an% > ca$se se*t(caem(c %(seases an% enter(c fe#er.:"*ho(% fe#er ?enter(c fe#er@ (s a ser(o$s h$man %(sease assoc(ate% B(th S . :"*h( an% S .Parat"*h(, Bh(ch are ma(nl" transm(tte% from h$man to h$man #(a the fecal!oral ro$te an% are*art(c$larl" Bell a%a*te% for (n#as(on an% s$r#(#al B(th(n host t(ss$es.>l(n(cal man(festat(ons of t"*ho(% fe#er ?enter(c fe#er@ a**ear after a *er(o% of (nc$bat(onran)(n) from to 74 %a"s ?$s$all" betBeen -8 an% 8 %a"s@ an% ma" (ncl$%e %(arrhea,*rolon)e% an% s*((n) fe#er, ab%om(nal *a(n, hea%ache, an% *rostrat(on.

E!"#,",$. :he most common ca$se of )astro(ntest(nal (nfect(ons (s serot"*es Bh(ch occ$r B(%el"(n an(mals an% h$mans. :he %(sease (s ca$se% b" the cons$m*t(on of foo%s Bh(ch arecontam(nate% B(th h()h n$mber non!host!s*ec(f(c salmonellae. :he se#er(t" of the %(sease ma"ran)e from as"m*tomat(c carr(a)e to se#ere %(arrhea.Salmonellos(s (s the most common t"*e./ost common ca$se of enterocol(t(s (s the non!t"*ho(% salmonellae, Bh(ch (s often transm(tte%b" foo% ?or Bater@.:he neBborns, (nfants, the el%erl", an% (mm$nocom*rom(se% (n%(#(%$als are more sens(t(#e tosalmonellos(s than health" a%$lts.:he (nc$bat(on *er(o% of the %(sease (s )enerall" betBeen 4 an% 1; h. :he most commons"m*toms of the %(sease are m(l% fe#er, na$sea, #om(t(n), ab%om(nal *a(n, hea%ache, ch(lls an%%(arrhea. :he s"m*toms are often accom*an(e% b" *rostrat(on, fa(ntness, m$sc$lar Beaness,restlessness, an% %roBs(ness.S"m*toms $s$all" *ers(st for a feB %a"s ?– %a"s@ b$t, (n some cases, the" can *ers(st for aBee or more. In th(s case some *at(ents ?$* to 7J@ ma" become carr(ers of the bacter(a.


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In most cases the %(sease (s self!l(m(t(n), b$t (n case of s$sce*t(ble h$mans ?e.). #er" "o$n), #er"ol% *erson@ (t can be more se#ere.:he mortal(t" rate (s 7.;J $n%er one "ear of a)e, J betBeen - an% 78 "ear, an% -7J o#er thea)e of 78 "ears. :he a#era)e mortal(t" (s 1.-J.:he (nfect(o$s %ose of salmonellos(s (s h()h ?abo$t -84–-86 cell)@, b$t (t %e*en%s on the

#(r$lence of the serot"*e, the s$sce*t(b(l(t" of the (n%(#(%$al an% the foo% #eh(cle (n#ol#e%.In case of some o$tbreas the (nfect(#e %ose Bas betBeen -8 an% -88 cells. :hese o$tbreasassoc(ate% B(th s$sce*t(ble h$mans an% fatt" foo%s ?e.). cheese, salam(, chocolate@. It (s %$e tothat the h()h fat content of foo%s can *rotect salmonellae form stomach ac(%(t".Salmonellos(s (s a zoonot(c %(sease, beca$se the ma(n so$rce of h$man (llness (s (nfecte%an(mals. :he transm(ss(on of the bacter(a (s b" the faecal–oral ro$te. In th(s case the foo% orBater (s contam(nate% b" the (ntest(nal contents of (nfecte% an(mals.Factors Bh(ch are contr(b$t(n) to o$tbreas are (na%eC$ate cool(n), stor(n) an% heat treatmentcon%(t(ons, f$rthermore cross!contam(nat(on. >ross!contam(nat(on can occ$r thro$)h %(rectcontact or (n%(rectl" #(a contam(nate% (tchen eC$(*ment an% $tens(ls. In case of Salmonella

transm(ss(on, h$man carr(ers are $s$all" less (m*ortant than an(mals.:he *r(mar" so$rces of salmonellos(s are foo%s of an(mal or()(n ?e.). *o$ltr", *o$ltr" *ro%$cts,meat, e))s, sala% %ress(n), ma"onna(se, an% $n*aste$r(ze% m(l@, b$t (n some cases *lant*ro%$cts ?e.). sala% #e)etables@ can also be assoc(ate% B(th that.:he folloB(n) meas$res hel* to re%$ce the transm(ss(on betBeen an(mals on the farmA! )oo% an(mal h$sban%r",! *rotect(on of fee%s an% Bater from contam(nat(on,! h")(en(c %(s*osal of Bastes, an%! ma(ntenance of a )enerall" clean en#(ronment.:here Bas a clear seasonal tren% (n conf(rme% salmonellos(s cases re*orte% (n the EU betBeen

88; an% 8-, B(th most cases re*orte% %$r(n) s$mmer months. :he s()n(f(cant %ecreas(n) EUtren% obser#e% for se#eral "ears cont(n$e% (n 8- ?F()$re .1.-@. :he n$mber of conf(rme%cases of h$man salmonellos(s (n 8- Bas 6-81, Bh(ch means a 1.9J %ecrease o#er the*re#(o$s "ear ?6771; cases (n 8--@.

F()$re .1.-A :ren% (n re*orte% conf(rme% cases of h$man salmonellos(s (n the EU betBeen 88;an% 8- ?EFS' – E>D>, 8-1@


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In the E$ro*ean Un(on, the tBo most commonl" re*orte% Salmonella sero#ars (n 8- ?l(e (nthe *re#(o$s "ear@ Bere S . Enter(t(%(s ?1-.J@ an% S . :"*h(m$r($m ?.-J@. 2ther commonsero#ars (n 8- ?(n the EU@ Bere mono*has(c S . :"*h(m$r($m ?9.J@, an% S . Infant(s ?.7J@?F()$re .1.@.

F()$re .1.A D(str(b$t(on of the -8 most common Salmonella sero#ars (n h$mans (n the EUbetBeen (n 8- ?EFS' – E>D>, 8-1@


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5.. E SC!E$%C!%A C"L% AND FOODBORNE GASTROENTERITIS CAUSED BY E SC!E$%C!%AC"L%

S,#!",, *%$$,,%",!

Doma(nA ='>:E


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-2 coli (s a t"*(cal meso*h(le )roB(n) from 9◦> $* to 78◦> B(th an o*t(m$m aro$n% 9◦>. SomeE:E> stra(ns are able to )roB at tem*erat$res as loB as 1◦>. It (s not res(stant to heat ?D48 T 8.-

m(n@, an% can s$r#(#e refr()erate% or frozen stora)e for e3ten%e% *er(o%s.

:he o*t(mal *0 for )roBth (s aro$n% ne$tral *0. :he m(n(m$m *0 for )roBth (s abo$t *0 1.1.

:he m(n(m$m Bater act(#(t" for )roBth (s 8.67.

In the -618s Ka$ffman *ro*ose% a serot"*(n) scheme for these bacter(a. :h(s scheme (s base%on somat(c ?2@, fla)ellar ?0@, an% ca*s$lar ?K@ ant()ens.:he 2 ant()en (%ent(f(es the sero)ro$* of a stra(n, an% the 0 ant()en (%ent(f(es (ts serot"*e.'t *resent, more than 988 serot"*es of -scherichia coli ha#e been (%ent(f(e%.

Patho)en(c -2 coli stra(ns are cate)or(ze% (nto s*ec(f(c )ro$*s ?*athot"*es@ base% on the(r#(r$lence %eterm(nants.:hese #(r$lence %eterm(nants (ncl$%eA

! controll(n) a%hes(ons ?>F'I>F'II, t"*e - f(mbr(ae, P f(mbr(ae, S f(mbr(ae, an% (nt(m(n@,! (n#as(ons ?hemol"s(ns, s(%ero*hores, s(%ero*hore $*tae s"stems, an% Sh()ella!l(e (n#as(ns@,! mot(l(t" ?fla)ella@,! to3(ns ?heat!stable an% heat!lab(le enteroto3(ns, Sh()a to3(ns _St3s`, c"toto3(ns, an%en%oto3(ns@,! ant(*ha)oc"t(c s$rface str$ct$res ?ca*s$les, K ant()ens, l(*o*ol"sacchar(%es _LPS`@, an%! )enet(c character(st(cs ?)enet(c e3chan)e thro$)h trans%$ct(on or con+$)at(on, transm(ss(ble*lasm(%s, < factors, an% %r$) res(stance an% #(r$lence *lasm(%s@.

V,6*#!# 6$ Escherichia coli

F(#e #(r$lence )ro$*s ?*athot"*es@ of -2 coli are reco)n(ze%A

• entero*atho)en(c -2 coli ?EPE>@,• enteroto3()en(c -2 coli ?E:E>@,• entero(n#as(#e -2 coli ?EIE>@,• enteroa))re)at(#e -2 coli ?E'E>@,• enterohemorrha)(c -2 coli ?E0E>@.

E!"#%"#!, E' coli EPEC

'mon) the -2 coli *athot"*e, entero*atho)en(c -2 coli Bas f(rst (%ent(f(e% an% %escr(be%. It Basf(rst character(ze% (n -677. EPE> stra(ns ca$se %(arrhea (n ch(l%ren )enerall" less than one "earof a)e. :he" can ca$se Bater" %(arrhea l(e E:E>. =$t EPE> %oes not ha#e the same colon(zat(onfactors as E:E> an% %o not *ro%$ce enteroto3(ns ?L: or S: to3(ns@. :he ma(n somat(c ?2@sero)ro$*s Bh(ch are assoc(ate% B(th (llness are the folloB(n)A 277, 2;4, 2---ab, 2--6,2-7ac, 2-4, 2-9, 2-;ab, an% 2-1. 0$mans are an (m*ortant reser#o(r.:he

Microbiological Aspects of Food Quality and Safety

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