CHNG I: TNG QUAN TI LIU1.1. Cu trc ca lignocellulose 1.1.1. Cu trc thnh t bo thc vt Trong t nhin, cc lp ca thnh t bo thc vt c minh ha bng m hnh ca g (Hnh 1.1). gia cc t bo, c mt hp cht ng vai tr nh keo dn gn kt cc t bo li vi nhau, l lp gian bo (middle lamella). Lp ny cu to t cc cht keo, c bn cht pectin v khng c tc ng v quang hc. Bn trong l thnh t bo s cp (primary wall).

Hnh 1.1: Cu trc thnh t bo thc vt [37] Thnh t bo s cp c th c chia thnh mt bn trong v mt bn ngoi. S sp xp ca cc vi si trong thnh t bo s cp phn tn tng dn t mt trong ra mt ngoi. Tip n l thnh t bo th cp gm 3 lp: lp ngoi (S1), lp gia (S2) v lp trong (S3). S phn chia thnh t bo th cp thnh ba lp S ch yu l do s nh hng khc nhau ca cc vi si trong ba lp . in hnh cc vi si nh hng xon trong vch t bo. Lp ngoi ca thnh t bo th cp, cc vi si c nh hng trong cu trc xon cho c nghing to thnh mt gc ln vi trc dc ca t bo. Lp

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gia l lp dy nht v lp gia c gc nh v nghing ca si xon c trong khi vi si trong lp 3 c sp xp nh lp ngoi, vi mt gc rng vi trc dc ca t bo. Ngoi ra trong mt s trng hp, trn mt trong ca thnh t bo c lp sn si (W). Chc nng ca thnh t bo l chng cho cc c quan ca cy c bit l cc vch dy v cng. Thnh t bo cn gi cc chc nng quan trng chnh nh hp th, thot hi nc hay vn chuyn v bi tit. Lignocellulose l thnh phn cu trc chnh ca thc vt thn g v cc thc vt khc nh c, la, ngTrong t nhin, chng ta c th tm thy lignocellulose thc vt hay cc cht thi nng nghip, lm nghip v cc cht thi rn trong thnh ph. Thnh phn ch yu ca lignocellulose l cellulose, hemicellulose v lignin (Hnh 1.2). Cellulose v hemicellulose l cc i phn t cu to t cc gc ng khc nhau, trong khi lignin l mt polymer dng vng c tng hp t tin phenylpropanoid. Thnh phn cu to v phn trm ca cc polymer ny l khc nhau gia cc loi. Hn na, thnh phn cu to trong cng mt cy hay cc cy khc nhau l khc nhau da vo tui,Hnh 1.2: Thnh phn ch yu ca

giai on sinh trng, pht trin ca cy v cc iu kin khc. Thnh phn ca lignocellulose c trnh by bng 1.1 [9].

lignocellulose

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Bng 1.1: Thnh phn lignocellulose trong rc thi v ph ph liu nng nghip ph bin [9] Ngun lignocellulose Thn g cng Thn g mm V lc Li ng Giy V tru V tru ca la m Rc phn loi L cy Ht bng Giy bo Giy thi t bt giy ha hc Cht rn nc thi ban u Cht thi ca ln Phn bn gia sc C b bin Bermuda C mm Cc loi c (tr s trung bnh cho cc loi) B th Cellulose (%) 40-55 45-50 25-30 45 85-99 32.1 30 60 15-20 80-95 40-55 60-70 8-15 6 1.6-4.7 25 45 25-40 Hemicellulose (%) Lignin (%) 24-40 25-35 25-30 35 0 24 50 20 80-85 5-20 25-40 10-20 28 1.4-3.3 35.7 31.4 25-50 18-25 25-35 30-40 15 0-15 18 15 20 0 0 18-30 5-10 24-29 2.7-5.7 6.4 12.0 10-30

33.4 30 18.9 Lng ln lignocellulose c thi ra t cc ngnh lm nghip, nng nghip,

cng nghip giy v gy ra nhim mi trng. Tuy nhin, lng ln cc sinh khi thc vt d tha c coi l rc thi c th c bin i thnh nhiu sn phm c gi tr khc nhau nh nhin liu sinh hc, ha cht, cc ngun nng lng r cho

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qu trnh ln men, b sung cht dinh dng cho con ngi v thc n cho ng vt [15]. 1.1.2. Cellulose Cellulose l hp cht hu c c cng thc cu to (C6H10O5)n, v l thnh phn ch yu ca thnh t bo thc vt, gm nhiu cellobiose lin kt vi nhau, 4O- (-D-Glucopyranosyl)-D-glucopyranose (Hnh 1.3). Cellulose cng l hp cht hu c nhiu nht trong sinh quyn, hng nm thc vt tng hp c khong 1011 tn cellulose (trong g, cellulose chim khong 50% v trong bng chim khong 90%).

Hnh 1.3: Cng thc ha hc ca cellulose Cc mch cellulose c lin kt vi nhau nh lin kt hydro v lin kt van Der Waals, hnh thnh hai vng cu trc chnh l tinh th v v nh hnh. Trong vng tinh th, cc phn t cellulose lin kt cht ch vi nhau, vng ny kh b tn cng bi enzyme cng nh ha cht. Ngc li, trong vng v nh hnh, cellulose lin kt khng cht vi nhau nn d b tn cng [40]. C hai m hnh cu trc ca cellulose c a ra nhm m t vng tinh th v v nh hnh nh hnh 1.4 [29].

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Hnh 1.4: M hnh Fringed fibrillar v m hnh chui gp Trong m hnh Fringed Fibrillar: phn t cellulose c ko thng v nh hng theo chiu si. Vng tinh th c chiu di 500 v xp xen k vi vng v nh hnh. Trong m hnh chui gp: phn t cellulose gp khc theo chiu si. Mi n v lp li c trng hp khong 1000, gii hn bi hai im a v b nh trn hnh v. Cc n v c sp xp thnh chui nh vo cc mch glucose nh, cc v tr ny rt d b thy phn. i vi cc n v lp li, hai u l vng v nh hnh, cng vo gia, tnh cht kt tinh cng cao. Trong vng v nh hnh, cc lin kt - glycoside gia cc monomer b thay i gc lin kt, ngay ti cui cc on gp, 3 phn t monomer sp xp to s thay i 180o cho ton mch. Vng v nh hnh d b tn cng bi cc tc nhn thy phn hn vng tinh th v s thay i gc lin kt ca cc lin kt cng ha tr ( - glycoside) s lm gim bn ca lin kt, ng thi v tr ny khng to c lin kt hydro [2]. Cellulose c cu to tng t carbohydrate phc tp nh tinh bt v glycogen. Cc polysaccharide ny u c cu to t cc n phn l glucose. Cellulose l glucan khng phn nhnh, trong cc gc glucose kt hp vi nhau

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qua lin kt -1 4- glycoside, chnh l s khc bit gia cellulose v cc phn t carbohydrate phc tp khc. Ging nh tinh bt, cellulose c cu to thnh chui di gm t nht 500 phn t glucose. Cc chui cellulose ny xp i song song to thnh cc vi si cellulose c ng knh khong 3,5 nm. Mi chui c nhiu nhm OH t do, v vy gia cc si cnh nhau kt hp vi nhau nh cc lin kt hidro c to thnh gia cc nhm OH ca chng. Cc vi si li lin kt vi nhau to thnh vi si ln hay cn gi l b mixen c ng knh 20 nm, gia cc si trong mixen c nhng khong trng ln. Khi t bo cn non, nhng khong ny cha y nc, t bo gi th cha y lignin v hemicellulose. Cellulose c cu trc rt bn v kh b thy phn. Ngi v ng vt khng c enzyme phn gii cellulose (cellulase) nn khng tiu ha c cellulose, v vy cellulose khng c gi tr dinh dng. Tuy nhin, mt s nghin cu cho thy cellulose c th c vai tr iu ha hot ng ca h thng tiu ha. Vi khun trong d c ca gia sc, cc ng vt nhai li v ng vt nguyn sinh trong rut ca mi sn xut enzyme phn gii cellulose. Nm t cng c th phn hy cellulose. V vy chng c th s dng cellulose lm thc n. 1.1.3. Lignin Lignin l mt phc hp cht ha hc ph bin c tm thy trong h mch thc vt, ch yu l gia cc t bo, trong thnh t bo thc vt. Lignin l mt trong cc polymer hu c ph bin nht trn tri t. Lignin c cu trc khng gian 3 chiu, phc tp, v nh hnh, chim 17% n 33% thnh phn ca g. Lignin khng phi l carbohydrate nhng c lin kt cht ch vi nhm ny to nn mng t bo gip thc vt cng chc v gin, c chc nng vn chuyn nc trong c th thc vt (mt phn l lm bn thnh t bo v gi cho cy khng b , mt phn l iu chnh dng chy ca nc), gip cy pht trin v chng li s tn cng ca cn trng v mm bnh. Thc vt cng gi, lng lignin tch t cng ln.

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Hn na, lignin ng vai tr quan trng trong chu trnh carbon, tch ly carbon kh quyn trong m ca thc vt thn g lu nm, l mt trong cc thnh phn b phn hy lu nht ca thc vt sau khi cht, ri ng gp mt phn ln cht mn gip tng kh nng quang hp ca thc vt. Lignin l mt polyphenol c cu trc m. Trong t nhin, lignin ch yu ng vai tr cht lin kt trong thnh t bo thc vt, lin kt cht ch vi mng cellulose v hemicellulose. Rt kh c th tch lignin ra hon ton. Lignin l polymer, c cu thnh t cc n v phenylpropene, vi n v cu trc in hnh l: guaiacyl (G), trans-coniferyl alcohol; syringyl (S), transsinapyl alcohol; p-hydroxylphenyl (H), trans-p-courmary alcohol (Hnh 1.5).

Hnh 1.5: Cc n v c bn ca lignin [14] Cu trc ca lignin a dng, ty thuc vo loi g, tui ca cy hoc cu trc ca n trong g. Ngoi vic c phn loi theo lignin ca g cng, g mm v c, lignin c th c phn thnh hai loi chnh: guaicyl lignin v guaicyl-syringyl lignin. G mm cha ch yu l guaiacyl, g cng cha ch yu syringyl. Cc nghin cu ch ra rng guaiacyl lignin hn ch s trng n ca x si v v vy loi nguyn liu s kh b tn cng bi enzyme hn syringyl lignin [29]. Nhng nghin cu gn y ch ra rng lignin hon ton khng ng nht trong cu trc. Lignin dng nh bao gm vng v nh hnh v cc vng c cu

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trc hnh thun hoc hnh cu. Lignin trong t bo thc vt bc cao khng c vng v nh hnh. Cc vng phenyl trong lignin ca g mm c sp xp trt t trn mt phng thnh t bo. Ngoi ra, c cu trc ha hc v cu trc khng gian ca lignin u b nh hng bi mng polysaccharide. Vic m hnh ha ng hc phn t cho thy rng nhm hydroxyl v nhm methoxyl trong cc oligomer tin lignin s tng tc vi vi si cellulose cho d bn cht ca lignin l k nc.

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Hnh 1.6: Cu trc lignin trong g mm vi cc nhm chc chnh Cc nhm chc nh hng n hot tnh ca lignin bao gm nhm phenolic hydroxyl t do, methoxyl, benzylic hydroxyl, ether ca benzylic vi cc ru mch thng v nhm carbonyl (Hnh 1.6). Guaicyl lignin cha nhiu nhm phenolic hydroxyl hn syringyl. Lignin to lin kt ha hc vi hemicellulose v ngay c vi cellulose (nhng khng nhiu). bn ha hc ca nhng lin kt ny ph thuc vo bn cht lin kt, cu trc ha hc ca lignin v cc gc ng tham gia lin kt [2]. Carbon alpha (C) trong cu trc phenyl propane l ni c kh nng to lin kt cao nht vi khi hemicellulose. Ngc li, cc ng nm mch nhnh nh arabinose, galactose, v acid 4-O-methylglucuronic l cc nhm thng lin kt vi lignin. Cc lin kt c th l ether, ester (lin kt vi xylan qua acid 4-O-methyl-Dglucuronic), hay glycoside (phn ng gia nhm kh ca hemicellulose v nhm OH phenolic ca lignin) Cu trc ha hc ca lignin rt d b thay i trong iu kin nhit cao v pH thp nh iu kin trong qu trnh tin x l bng hi nc. nhit phn ng cao hn 200oC, lignin b kt khi thnh nhng phn ring bit v tch ra khi cellulose. Nhng nghin cu trc y cho thy i vi g cng, nhm ether -O-4 aryl b ph hy trong qu trnh n hi. ng thi, i vi g mm, qu trnh n hi lm bt hot cc nhm hot ng ca lignin v tr nh nhm hydroxyl hay ether, cc nhm ny b oxy ha thnh carbonyl hoc to cation benzylic, cation ny s tip tc to lin kt C-C [29]. Trong dinh dng ng vt, lignin rt ng quan tm v n khng b tiu ha bi enzyme ca c th vt ch. Lignin cn lin kt vi nhiu polysaccharide v protein mng t bo ngn tr qu trnh tiu ha cc hp cht g. G, c kh v rm rt giu lignin nn t l tiu ha thp tr khi c x l ha hc lm cho cc lin kt gia lignin vi cc carbohydrate khc b b gy.

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1.1.4. Hemicellulose Hemicellulose l mt loi polymer phc tp v phn nhnh, trng hp khong 70 n 200 n phn. Hemicellulose cha c ng 6 carbon gm glucose, mannose v galactose v ng 5 gm xylose v arabinose. Thnh phn c bn ca hemicellulose l D xylopyranose, lin kt vi nhau bng lin kt -(14). Cu to ca hemicellulose kh phc tp v a dng ty vo nguyn liu, tuy nhin c mt vi im chung gm:-

Mch chnh ca hemicellulose c cu to t lin kt -(14). Xylose l thnh phn quan trng nht. Nhm th ph bin nht l nhm acetyl O lin kt vi v tr 2 hoc 3. Mch nhnh cu to t cc nhm n gin, thng thng l disaccharide hoc trisaccharide. S lin kt ca hemicellulose vi cc polysaccharide khc v vi lignin l nh cc mch nhnh ny. Cng v hemicellulose c mch nhnh nn tn ti dng v nh hnh v v th d b thy phn.

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Hemicellulose l polysaccharide trong mng t bo tan trong dung dch kim v c lin kt cht ch vi cellulose, l mt trong ba sinh khi t nhin chnh. Cng vi cellulose v lignin, hemicellulose to nn thnh t bo vng chc thc vt. V cu trc, hemicellulose c thnh phn chnh l D-glucose, D-galactose, D-mannose, D-xylose v L-arabinose lin kt vi cc thnh phn khc v nm trong lin kt glycoside. Hemicellulose cn cha c axit 4-O-methylglucuronic, axit Dgalacturonic v axit glucuronic. Trong , ng D-xylose, L-arabinose, D-glucose v D-galactose l ph bin thc vt thn c v ng cc. Tuy nhin, khc vi hemicellulose thn g, hemicellulose thc vt thn c li c lng ln cc dng lin kt v phn nhnh ph thuc vo cc loi v tng loi m trong cng mt loi cng nh ph thuc vo tui ca m .

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Ty theo trong thnh phn ca hemicellulose c cha monosaccharide no m n s c nhng tn tng ng nh manan, galactan, glucan v xylan. Cc polysaccharide nh manan, galactan, glucan hay xylan u l cc cht ph bin trong thc vt, ch yu cc thnh phn ca mng t bo ca cc c quan khc nhau nh g, rm r, v.v Trong cc loi hemicellulose, xylan l mt polymer chnh ca thnh t bo thc vt trong cc gc D-xylopyranose kt hp vi nhau qua lin kt -1,4-Dxylopyranose, l ngun nng lng di do th hai trn tri t. a s phn t xylan cha nhiu nhm trc chnh v chui bn [7]. Cc gc thay th ch yu trn khung chnh ca xylan l cc gc acetyl, arabinosyl v glucuronosyl. Cc nhm ny c c tnh lin kt tng tc cng ha tr v khng ha tr vi lignin, cellulose v cc polymer khc [32]. Cu to, s lng v v tr ca xylan cc loi thc vt khc nhau l khc nhau. Xylan tn ti dng O-acetyl-4-O-methylglucuronoxylan cy g cng (Hnh 1.7), hay arabino-4-O-methylglucuronoxylan cy g mm (Hnh 1.8) [39], hay thnh phn cu to xylan l axit D-glucuronic, c hoc khng c ete 4-O-methyl v arabinose cc loi ng cc.

Hnh 1.7: O-acetyl-4-O-methylglucuronoxylan cy g cng

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Hnh 1.8: Arabino-4-O-methylglucuronoxylan cy g mm 1.2. Enzyme thy phn lignocellulose Hu ht nhng quy trnh x l rc thi u s dng mt trong hai phng php ha l hoc sinh hc hoc kt hp. Phng php x l bng enzyme l trung gian gia hai phng php truyn thng, n bao gm cc quy trnh ha hc trn c s hot ng ca cc cht xc tc c bn cht sinh hc. Enzyme c th hot ng trn cc cht nhim c bit kh x l loi chng bng cch kt ta hoc chuyn chng thnh dng khc. Ngoi ra chng c th lm thay i cc c tnh ca cht thi a chng v dng d x l hoc chuyn thnh cc sn phm c gi tr hn. Phng php x l bng enzyme so vi phng php x l thng thng c nhng u im vt tri nh: p dng c i vi cc hp cht sinh hc kh x l; tc dng c vng nng cht nhim cao v thp; mt s enzyme ring bit c tc dng trn phm vi ca pH, nhit , mn; khng gy ra nhng bin ng bt thng; khng nh hng n cn bng sinh thi.

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Da trn phng php enzyme hc v qu trnh phn hy cellulose, hemicellulose v lignin ngy nay c mt vi phng php sinh hc thc hin chu trnh x l lignocellulose. Trong tng lai gn, cc quy trnh s dng enzyme thy phn lignocellulose hoc da vo vi sinh vt c th mang li cho chng ta nhiu li ch ln v thn thin vi mi trng. Mi quan h gia cellulose v hemicellulose trong thnh t bo thc vt bc cao cht ch hn chng ta tng trc . c th l do cc phn t ti cc lin kt cellulose-hemicellulose hoc ti cc vng cellulose tinh th i hi phi c cc enzyme khc nhau thy phn hiu qu hn. Mi polymer b thy phn bi mt s vi sinh vt sn xut cc enzyme hot ng h tr nhau. Nu ng nh vy, iu ny c th gip chng ta gii thch c ti sao vi sinh vt cellulolytic tng hp c trng nhiu enzyme cellulase khc nhau c tnh c hiu gi nhau v ti sao mt s enzyme xylanase li mang vng lin kt c cht gn vi cellulose. Cc vi sinh vt cellulolytic v xylanolytic khng trong mi trng ring bit m chng tn ti cng vi cc loi khc nh nm v vi khun. Cc chng ny s ng vai tr nh trung tm thy phn polymer to ra ng v cc sn phm thy phn khc. 1.1.5. Enzyme cellulolytic Enzyme thy phn cellulose c kh nng thy phn cht thi cha cellulose, chuyn ha cc hp cht kiu lignocellulose v cellulose trong rc thi to nn ngun nng lng thng qua cc sn phm, ethanol, kh sinh hc hay cc sn phm giu nng lng khc. Th d nh t cc cht thi nh my giy nh cc sn phm t bt giy v giy c th thu ngun nng lng nh ethanol [12]. Lin kt ch yu trong cu trc ca cellulose l -(14) glucoside. Ni chung, ph hy hon ton cu trc ca polysaccharide ny cn c cc enzyme cellulase vi nhng tc ng c trng ring bit. Da theo nghin cu v h

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enzyme cellulase ca nm Trichoderma reesei [36], h enzyme thy phn gm 3 loi hot tnh enzyme (Hnh 1.9): Endoglycanase hoc 1,4--D-glucan glucanohydrolase (EC 3.2.1.4) Enzyme ni bo endoglycanase hoc 1,4--D-glucan glucanohydrolase l enzyme thy phn ni bo lin kt 1,4--D-glucosidic trong phn t cellulose bi tc dng ngu nhin trong chui polymer hnh thnh cc u chui kh t do v cc chui oligosaccharide ngn. Cc endoglucanase khng th thy phn cellulose tinh th hiu qu nhng n s ph v cc lin kt ti khu vc v nh hnh tng i d tip cn. Exoglucanase Enzyme ngoi bo exoglucanase gm c 1,4-beta-D-glucan glucanohydrolase (EC 3.2.1.74), gii phng D-glucose t -glucan v cellodextrin v 1,4-beta-D-glucan cellobiohydrolase (EC 3.2.1.91) m gii phng D-cellobiose. T l thy phn ca enzyme cellobiohydrolase ngoi bo b hn ch bi s sn c cc u chui cellulose. -glucosidase hay -D-glucoside glucohydrolase (EC 3.2.1.21) -glucosidase hay -D-glucoside glucohydrolase gii phng phn t Dglucose t ng cellodextrin ha tan v mt lot cc glucoside khc.

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Hnh 1.9: Tc dng ca tng enzyme trong cellulose

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1.1.6. Enzyme xylanolytic Do tnh khng ng nht ca xylan, s thy phn ca n i hi cc nh hng ca mt h thng enzyme phc tp. Enzyme ny thng bao gm hai loi: enzyme khng phn nhnh (-1,4-endoxylanse, -xylosidase) v enzyme phn nhnh (-arabinofuranosidase, -glucuronidase, esterase xylan acetyl v esterase axit phenolic) (Hnh 1.10). Tt c cc enzyme ny tc ng tng h chuyn i xylan thnh cu t ng ca n. H thng enzyme xylanolytic a chc nng nh vy kh ph bin nhng vi khun v nm. Cc xylan khc loi cha nhm th khc nhau trong mch chui chnh v chui bn. Nh vy, s phn gii polysaccharide phc tp nh vy c th gm hot ng h tr gia cc thnh phn khc nhau ca h thng enzyme xylanolytic [7].

Hnh 1.10: (A) Enzyme xylanolytic lin quan n qu trnh phn gii xylan. Ac: nhm acetyl; -Araf: -arabinofuranose; -4-O-Me-GlcA: -4-O-methylglucuronic acid. (B) Thy phn cc xylooligosaccharide bi enzyme -xylosidase [10]

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-Xylosidase -D-xylosidase (-D-xyloside xylohydrolase; EC 3.2.1.37) l enzyme ngoi bo exoglyosidase thy phn cc oligosaccharide ngn v xylobiose thnh ng xylose. -xylobiose tht c th phn tch cht nhn to nh p-nitrophenyl -Dxyloside [11]. Trong s cc xylooligomer, xylobiose thng l c cht tt nht. i lc ca enzyme i vi xylooligosaccharide gim theo mc tng ca phn ng polymer ha [4]. Hu ht cc -xylosidase c nghin cu cho n nay u b c ch bi xylose sn phm thy phn ca chng. Nhiu -xylosidase c hot tnh transferase, c bit l cc nng c cht cao, to ra sn phm phn t lng cao. -L-Arabinofuranosidase Mc d enzyme arabinosidase ng vai tr quan trng trong qu trnh thy phn xylan, ch c mt vi enxyme c c lp v m t. C hai loi enzyme arabinase, cc enzyme -L-arabinofuranosidase ngoi bo (EC 3.2.1.55) hot ha ngc li vi p-nitrophenly--L-arabinofuranoside v trn cc arabinan phn nhnh, v cc enzyme 1,5-alpha-L-arabinase ni bo (EC3.2.1.99), ch hot ha cc arabinan dng thng. -L-Arabinofuranosidase c kh nng thy phn c hai lin kt 1,3- v 1,5-L-arabinofuranosyl trong arabinoxylolan c bo co trong A. ninger v B. subtilis. Enzyme ny c hiu cao i vi arabinoxylan v c th gii phng mi arabinose t arabinoxylan. Khi gii phng arabinose, mch chnh xylan khng b thy phn v khng to ra xylooligosaccharide. Enzyme ny khng tc ng i vi -L-1,3 hoc -1,5 lin kt arabinose t arabinan, arabinogalactan, hoc pnitrophenyl-alpha-L-arabinofuranoside. -Glucuronidase

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-D-Glucuronidase phn gii lin kt -1,2 gia axit glucuronic v gc xylose trong phn t glucuronoxylan. Tnh c hiu ca -glucuronidase l khc nhau ph thuc vo ngun gc ca enzyme.

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Esterase acetylxylan Enzyme esterase acetylxylan l enzyme c th ct t gia cc nhm acetyl vi 2 hoc 3 v tr ca gc xylose v gp phn ng vai tr thy phn xylan trong t nhin [8]. Trong cc nghin cu trc chng minh c enzyme ny c chng minh l sinh ra t mt s loi vi khun v nm [20,31]. 1.3. ng dng ca enzyme lignocellulolytic Th h nhin liu sinh hc u tin da trn ng, tinh bt v du thc vt, khng c c nhng ng dng rng ri trong cng nghip, v cc nguyn vt liu ny cng c s dng lm thc n. Lignocellulose c xem l th h nhin liu sinh hc th hai. Trong thp k qua, enzyme thy phn lignocellulose ngy cng c quan tm. Cellulose v xylan rt ph bin trong t nhin. Hng nm, lng lignocellulose do thc vt tng hp nn l 1011 tn. S phn hy lignocellulose ch yu l do vi sinh vt. Do m qu trnh phn hy lignocellulose bng cc enzyme t vi sinh vt c mt ngha ln v l thuyt cng nh v thc t. Bi l do vi sinh vt phn hy cellulose m hng nm bu kh quyn ca tri t c b sung y lng CO2 cn thit cho s sng. Mt s ng dng chnh ca cellulase v xylanase nh:

ng dng trong qu trnh thy phn g v ph liu g r tin thnh cc ng n gin ri c th ch bin thnh thc n cho gia sc. Cc nguyn liu thc phm c ngun gc thc vt nu c gia cng bng ch phm enzyme cellulase v xylanase s c mm ra, tng h s ng ha v cht lng. Do s rt b ch lm thc n c hiu cho tr em, ngi n king cng nh ch bin thc n gia sc.

ng dng trong qu trnh thy phn cht thi cha cellulose, chuyn ha cc hp cht kiu lignocellulose v cellulose trong rc thi to nn ngun nng lng thng qua cc sn phm ng, ethanol, kh sinh hc hay cc sn

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phm giu nng lng khc. Th d: t cc cht thi nh my giy nh cc sn phm t bt giy v giy c th thu ngun nng lng nh ethanol.

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