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" , ° '°°'' ' 7 "'"' " '•'""•• " « " "•"»"«• " ' "ir™ chd, luong eh„m vd chi,o,an Ticklioa Lplainarum VTCC43i, L bulgarici,, fTCC 703, vo dim ,dn, cliiio„m cliilm '\B,S1R,\CT
and ,iZ:::z::i:z:,::!::; r r - T"" ""- '"-"• -^""" •" '•-•' - ^•'"•-
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i''7.ici,i,,iioiicondi,L:^i::: : : : . . : x ^ ^ '•"'"""" "-"• -"™™'»
hevvoids-Lpiamarum VTCC4Sf L hulgoriciis VTCC JOf head, and,hel. „ ,h.m::!::::, el.nm I. BAT VAN o e ,.
" * n - i t r . n g . c h . h i . n c 0 ^ n h u . u . j = : : S ^ ^ ^ r ^ ^ ^ - ^ r r i r ^ :
ThS Le Phuong Chung, 5 Hoang ThI Bao Yen Vien r h n n n n h a . ^ ^
Vien Cong oghe smh hoc va Mo, laiong - Trumg 6ai hoc Nha Traog TRLfONG OAI HOC NHA TRANG . 11
Tap chi Khua hoc - Cong nghe Tlun
'"^ i \ i ^ ^ j ^ fir Sd i/2016 gop mot ty trong lan trong kim ngach xuat khau
Ihijy san Theo su' phat tnen chg bien thuy san, mot vin a^lon. i3ang duoc quan tam la phelieu tiJ' cong nghiep che bign, trong i36 co phg lieu tu' chg bign torn xuat khau Ngu6n phe lieu nay neu khong du'oc xi> ly hay tan dtjng mot each hieu qua se gay 6 nhiem moi truong Trong phe lieu torn co cht>a protein, astaxanthin, chitin, la nhu'ng chit rat hu'u ich Do 66.
ngoai viec dung phi lieu torn de che bi4n thO'c an chan nuoi, chiing ta co th§ sii' dung chiing de san xuat chitin va chitosan mang lai gia tn kinh te cao (Trlin Thi Luygn. 1995)
Chitin va dSn xuat ciia no la chitosan la nhu'ng polysacchand mach thSng Chitin ton tai a ca dong vat va thirc vat 6' dong vat thuy san, chitin co nhieu a vo torn, cua ghe (Tran Thi Luyin va cong 5u\ 2005) Vi vay, vo torn, cua ghe la nguyen phe lieu doi dao <3e san xult chitin-chitosan Hien nay, cong nghe san xuat chitin va chitosan chij yeu theo phu'ong phap hoa hoc dung HCI, NaOH dg khu' protein va khoang chit Nhu'O'c diem cua cong nghe nay la gay 6 nhiim moi truang, an mon thiet bi, chi phi san xuat cao, chua tan thu duoc cac thanh phln CO gia tn nhu protein, chit mau tir phe heu thuy san Nhiiu nghien cuu da duac thuc hien nham cai thien quy trinh, han c h i nhuo'c diem, tang hieu suit thu hii cac thanh phln co ich, trong do sir dung vi smh vat ho tro la mot trong nhung giai phap duoc nhiiu nha nghien cuu quan tam (Trang ST Trung, 2008)
Len men lactic la mot trong nhung ky thuat phat tnin tu lau doi va duac con nguai ung dung sum nhat trong bao quan va che bien thuc pham (sua len men. thit len men, rau len men, cac san pham do uong ) cung nhu trong nhieu ITnh vuc khac nhu y duo-c, hoa chat va chan nuoi (Nguyin Trong Can va cong su, 2006) Trong diiu kien co mat nguin CO chal carbohydrat (saccharose glucose, fructose, tmh bot ngo, tmh hot san ), vi khuan lactic se len men carbohydrat tao thanh acid lactic va san smh enzyme protease Acid lactic se tac dung vai phln canxicacbonat
i : • TRLIONG DAI HOC NHA TRANG
trong vo tom de tao thanh iactatcanxi 6 dang khong hoa tan (Nguyin Difc Luang, 2001), Phan irng nay g i n tuang icng viyi qua trinh khCf khoang boi HCI trong phu'ong phap hoa hoc D i n g thai he enzyme protease se thuy phan mot phan protein co trong vo torn lam tang qua trinh khu- protein khoi vo d i u torn Vi vay viec su dung vi khuan lactic trong qua trinh len men khi> khoang va protein tren vo dau tom hua hen se nang cao hieu qua san xuat chitin. chitosan va han che o nhilm moi trifffng.
II. eOl TU-ONG VA PHU'O'NG PHAP NGHIEN CLTU 1. Do! lu'p'ng nghten CLPU
Vi khuan giing: su dung hai chung vi khuan lactic L plantarum VTCC 431 va L. bulgaricus VTCC 703 do Bao tang giing chuan Viet Nam (VTCC), Dai hoc Quoc gia Ha Npi cung cap,
Nguyen lieu dau torn the chan tring d i u v6 torn the chan tring thu nhan tai b^n c h i bten cua Cong ty Co phln Nha Trang Seafoods - F17. Vo dau torn sau khi thu nh$n, riia sach, van chuyen ve Phong thi nghi?m Cong nghe Thuc pham - Truang Oai hoc Nha Trang, dong lanh va bao quan a -20''C de dung d i n trong qua trinh nghien ciru.
2. Phu'O'ng phap nghien ci>u
2 1. Phuxyng phap xir ly tniu Truac khi tien hanh nghien cii'u, nguyen lieu diu torn du'pc rua sach, xay nho bing may xay voi kich cd nguyen lieu tif 4-6 mm, tron deu, can cho vao tui polymer (lOOOg/tiii) va bao quan dong a nhiet dp -20''C de dijng cho qua trinh nghien ciru
2 2. Phuvng phap phan tich
- Xac dmh ham luang am bing phuong phap say kho a nhiet dp lOS-'C theo TCVN 3700 - 1990.
- Xac dinh ham luai ig khoang bang phuang phap nung o SSO^C theo TCVN 4588 - 1988
- Xac dinh ham luang protein con lai bing phuang phap Microbiuret
iMcMjawa hoc - Coin mhi Tlniy san
- Xac dmh mai ijp t4 bao vi khuan bang Phu'O'ng phap ijo OD a baac sting 600 nm k§t hcrp phuang phap Sim khuin lao (Trjn Linh Thuoc, 2007).
- Xac dinh hieu suit khir khoang va khu protein di,a tren cong thuc cua Rao va cong sv (2000)
• CiSc so lieu dugc xu ly va ve do thi bing
phin m i m MS EXCEL 2010
III. KET QUA NGHIEN CLfU VA THAO LUAN p. Thanh phin hoa hoc cua dau torn the Chan trang
K i t qua phan tich thanh phin hoa hoc co' ban cua d j u vo torn the chan tring duoc trinh bay d' bang 1
^^!^^yy;''^^'>^Vi^nhiah^^ ,a^ ,h^ ^^5„ ,^j„g
Ham lugng khoang Ham luang lipid Chllm
•Kit qua Unh iheo ham luang chil kho luyel do, Ket qua phan tich cho thiy d i u torn chCra 4 ,hanh phan chinh la protein, khOiSng. lipid va chitin Trong do protein chiem ham i w n g Idn nhat (48,6%) - kel qua nghien ciiu nay cao ban sa vol thiShh phan proetin d i u vo tdm the chan trang ma Trang Si Trung da phan lich nam 2008 Su^khiSc biet nay co t h i la do mua vu viS thdi diem lay m i u Ham luong lipid (5,8%) cung cao hon nhieu so vrii ham luang lipid chi CCI a phin vd tom (4,7%)
2. Nhan giong vl khuan
Chung giing L. plantarum VTCC 431 va L bulgaricos VTCC 703 duac boat hda tren moi trudng MRS agar Khuin lac dac tri/ng cho L p/an/ar-iym VTCC 431 cd hinh Iron, nhin, min
Ham liFO-ng (*) 48.6 25,2 5,8 i 17,9
±1,3 1 t0,6 1 0.3 1 t0,5
misu tring sua. Quan sat vi khuan L. plantarum VTCC 431 dudi kinh hliu VI thiy ring L plantarum VTCC 431 la true khuin Gram duong. cd dang hinh que nhd. khdng smh bao tu. khong dl ddng Khuin lac dac trung cho L bulgaricus VTCC 703 phang. hai viSng, du'dng kinh 2 - - 3 mm, khuan lac cang gia thi cang trd nen sam mau Vi khuin L bulgaricus VTCC 703 la true khuin Gram du'dng. hinh que dai. mianh thuang x i p thanh chuSi dai, khong cd kha nang di ddng Tidn hanh nhan giong tren mdi trudng MRS Idng va lie 150 vong/phut
Sau cac khoang thdi gian 2, 4,. 30h tion hanh xac dinh mat do l i bao trong dich nuoi c i y kit qua t h i hien d hinh 1 va hinh 2 nhu sau
ll*t|tarail^^tt,^[p
Hinh I. Vnh l,„m|, cua Ihm gian „„«! j f „ ,,, ,,„
IriroTi.; cua ,i khuan L ptanrarum \'TCC 431 Hinh 2. Anh hironi; cua thoi gian nuolTc^u^fnl trirmg cu. , i khuin i . fa./jar.cus V ICC 703
TRl/ONG OAI HOC NHA TRANG . 13
Tg2_chi Khoa hoc - Cong nghi Tim- sdn iactatcanxi 6 dang khong hoa tan (Rao va cs, 2001 va 2005). Vr vay ham iutmg protein va khoang con lai trong diu vo tom giam dang kk Tif phan tich o- Iren cho thiy ty le dich vi khuan bo sung vao nguyen lieu diu tom thich hpp la 10%.
3.2. Xac dinh thai gian len men khCf protein va khif khoang
S"' ^Mng 2 chiing L plantamm VTCC 431
So I 20J 6 va L buigancus VTCC 703 d l len men vo d i u tom vcri tl le vi khuan bd sung 10% (v/w) 6 pH 7,2 va len men a nhiet do phong vai thai gian len men khac nhau. Sau khi len men t i l n hanh ep tach djch len men. n>a sach va s l y kho d i n ciing do am ia 11%. K i t qua phan tich ham luang protein va khoang con lai a vo d i u tom dugc trinh bay a cac hinh 7 -10
S 5
'^IZ-BJlLTBlLM
108 UO iii J44 1S6 168 tWiri ttrAi Lplantarum (h)
Hinh 7. Sir tiiay Aii ham lu^tig klioang con iai o „
lau torn ibeo thoi gian len men bSng « khuin L.plantamm Hinh 8. Sy thaj doi ham lirong khoang con lai a \ L lau torn theo Ihdi gian len men bing \i khuin Lbuigaricus
Hlnh 9. Sir thaj doi ham Iirang protein or \6 dau torn theo thoi gian Jen men bSng
\) l<huan L.planlarum Kit qua phan tich cho thiy thai gian len men CO quan he nghich bien vai ham iu>ang protein va khoang con lai a vo dau torn sau qua trinh len men Trong gim han nghien ciru. cang tang tho/
gian len men thi ham lugng protein va khoang con l?^t a dau vo tom cang giam. Nhung cang ve CUOI qu^ trinh len men, mirc dp gjam ham lu'gng pnotein va khoang chit con lai a vo diu Bang 2. Thong so thich hwp cho qua trini
L. plantarum VTCC 4 3 t
Hinh JO. Sy tha) doi ham \\tqag protein eon lai ff \6 dau tom theo thoi gian len men bing
11 khuan L.bulgancus tom cang cham. Do vay de t i l kiem thai gian ma hieu qua khu protein va khoang vin dat yeu cau, nen dirng tiial gian len men a giai doan 132 h.
Tir k i t qua phan tich tren cho phep lua chon thong s6 thich hgp cho qua trinh khu khoang va protein tren d i u vo tom t h i bang cac Chung vi khuan L. plantamm VTCC 431 va L bulgaricus VTCC 703 a bang 2 ih khi> khoang va protein bing djch vi khuan Iva L. bulgaricus VTCC 703
IRU'ONG DAI HOC NHA TRANG •
Tap i hi Khoa lioc - C ong nglie Tlun san
3 3 Xac 6inh che 66 khu khoang bang HCI Sau kh! tien hanh ien men khir khoang va protein bing djch vi khuan, tien hanh khu khoang
So 1/2016 cdn lai a vo dau torn bing acid HCI. Ket qu^
nghien cuu khu khoang con lai bing HCI 6\jt^
trinh bay a hinh 11 va 12.
1
1.47I I I I
ZOO ZSO EDO 3 50 4 00 4 5D 5 00 Hong (fa dung JidiHClpo) Hinh 11 Anh hiroTig cua nfing do dung dich HCI
diin hiim lu-gTig khoanj; con lai ff dau \ o lorn da
\v K bang \ i khuan L.plantamm Ket qua trinh bay a hinh 11 va hinh 12 cho thay cang tang nong do HCi su' dung thi ham luong khoang con lai o dau torn giam cang manh Khi nong dd HCI la 4,0%, ham luo'ng khoang con iai 6 vo dau tom da xu' ly bang vi khuan L plantarum VTCC 431 giam chi con 0,70% (ham iuang khoang ban dau ciia vo dau torn la 13,1%), con doi vai m i u da xu ly
I I
Hinh 11. \nh hu-iiTig ciia thoi gian den liiim luong khoang con lai^o \o dau lorn xir l> b^ng dung djch HCI 4"'„ (doi sin mau da \u-1>' b i n g x i khuan L. planluiuin)
Ket qua phan tich trinh bay a hinh 13 va hmh 14 cho thiy d6i vai mau d i u vo torn da xu' ly bang dung dich vi khuin L plantarum VTCC 431 VOI nong do HCI su'dung4,0%, thai gian khu khoang cang dai thi iuang khoang khCr duac cang nhieu, sau 17h xu iy luong khoang con lai 6 dau vo torn chi la 0,47% (ham iuong khoang
If* • TRLfONG DAI HOC NHA TRANG
4S s I N6ng(ia(limgd|dliKO(9i>] j Hinh 12. Anh huong cua nong do dung dich HCI den ham Ivgng khoang con lai a dau vo torn da i v l y
bang vi khuan L.bulgaricus bang vi khuan /_. buigancus VTCC 703 thi h^m luang khoang giam con 1,22% Khi nong dp HCI SU' dung lan han 4,0% ham luang khoang con lai a vo d i u tom giam khong dang kl so vo'i m i u xu ly su dung n6ng dp HCI \A 4,0%.
Do vay, de dam bao du'ac hieu qua va chal luang chitosan thanh pham sau nay, nlng dp HCi 4.0% la thich hap.
• 189
I I ,u
• • 0<I1
I I I I I
J4 15 16 17 IB 19 Th&lglanih) H i n h 14. A n h h u m i g ciia t h o i gian a6n hitm lirflug k h o a n g con l a i o vti dau torn xir I;* bSng dung djch HCI 4 % ( d o i vo'i m a u d a xir Iy b a n g v i k h u i n L. bulgaricus)
ban dau con lai a v o d l u tom la 13,1%), con doi vai m i u da xi> ly bang vi khuan L buigancus VTCC 703. ham lugng khoang con lai 6 vo d i u torn la 0,92% (ham luang khoSng ban d i u con lai a vo dau tom la 14,65%) Sau 1?
h tra dl luang khoang trong d i u vo torn gi^m khong dang ke. Thai gian ngin thi qua trinh
^aiShUg^oahoc^Cmiij^ohlT^^
k h i khoang se khong tnet ai, ngu.<,c lai nSu ttoi gian da, thi se anh hL/ong a i n chit l„ong cua chitin thanh pham. Nhip vay tho, gian thich hop cho qua tnnh khCf khoang la 17h.
Theo Rao va cong su (2001 va 2005) trong quy tnnh san xuit chitin - chitosan t i , p h i lieu yo tom thi cong aoan k h i khoang bing HCI anh huong nhiiu nhit a i n kich thi/oc va do
"hot cua chitosan thu au^oc. H i u h i t cac su.
suy giam trong lu'ong cua chudi chitin xay ra trong va, phut a i u tien va cac san phim hinh thanh la oligosaccharid. Tir do cho thSy ring viec tang ham krong HCI se cho hieu suit khir khoang cao nhung se anh hu'dng x i u d i n chit lumig^chitin va chitosan thu amn sau nay
Hinh 15. Anh hurnig c . njnj a j d„„ a,jj ^ ^ ^ clen l,.m Immg proie.n c6n 1,1 „ ,6 dSu ion, ( d j i , j ,
niiiii Ja w I, binj ,, i | , „ i „ ^ , , , „ , „ „ , „ ^ Ket qua tnnh bay a hinh 15 va hinh i f i cho thay 6 ciing mot chi do xi> ly. cang tang nong ao NaOH s i dung thi lirong protein bi khu' cang nhieu. a nong do NaOH tir 2 0% va 4.0%, sau 12 gid' thuy phan, ham lu'ong protein con lai d vo aau tdm tuong i n g la 2 49%
ViS 0.74% <I<iivm m i u a a x i l y bing Chung
So 1 21116 Su suy giam mach polysacchand cua chitin xay ra thdng qua viec acid HCI thuy phan cat dut lien k i t glucosid. Vi vay viec tang cao ndng ao HCI va thoi gian thuy phan phai dam bao hop ly a i tiet kiem hda chit va giam thdi gian thuy phan. t i , ad giam chi phi san xuit nhung van dam bad duoc v i n 36 quan trong la cac yeu to tren khdng tac dong d i n viec c i t mach polysacchand cua chitin
3 4. Xac tmh chi ad khu-protein bang NaOH Sau khi khu kheiSng va protein cdn lai d vd dau tom sau len men bing HCI. tiin hanh khir protein con lai bing NaOH Ioang K i t qua k h i protein cdn lai bing NaOH duoc trinh bay d hinh 15 va hinh 16
Hinh 17. \nli hmhiE eua ibfri gian xir I, den
\a()FU-. dSn ham lin/nc protein con lal'ldSi ,„
man da , „ |, d|cli ,i khuin t. planinmm)
H.nh 16. *„h h ™ . coa „6„g do dong dich NaOH den ham tag pe„,ei, eon la, o .o din , 6 „ ,d6i , "
man da vii K bang vi khnan i . bulgarieu,]
L plantarum VTCC 431. cdn dOi vd, m i u da xu ly bang chung L buigancus VTCC 703 luong protein con lai tuong i n g la 3.87% va 1 0 1 % Khi nong ad NaOH s i dung Idn hon 4 0%
ham luong protein k h i duoc tang khong dang ke Do vay nong do NaOH thich hop Se k h i j)roteinj;dn lai sau len men la 4,0%.
Hinh 18. \nh hiro NaOH J% d^n ham lirirn,
11,1> dich
thm" gian \ir K dfn lai (dfi,, i . tiut^ark-u,,
muOhIG OAI HOC NHA TRANG . I 7
Tap chi Khoa lioi - Cong ig^hc Tlun scui So 1/2016 Ket qua trinh bay a hinh 17 va hinh 18 cho
thay thai gian cang dai, hieu qua khu protein cang cao, luong protein khu duoc cang nhieu Sau 13h khu protein bing NaOH 4,0%, ham luang protein cdn lai o vo dau tom tuo'ng ung la 0.86% va 1,07% d6i voi cac miu da xu' ly bang L. plantamm VTCC 431 va L bulgaricus VTCC 703. Sau 66 neu tang thai gian xu ly tren 13h hieu qua khu protein gin nhu khong doi Ngu thai gian xu ly ngan han 13h, qua tnnh khu prolem khong tnet Do dd thai gian duoc chon de khu protein sau len men bang NaOH 4,0% la 13h
Nhu vay, qua trinh khu protein cdn lai tren diu vo tdm bang NaOH phu thudc rit Ion vao nong do NaOH va thai gian Quy luat bien doi ciia ham luong protein la khi tang
n6ng do NaOH va thai gian thiJy phan se l^m giam ham luang protein cdn lai trong vo dau tdm Nhigu nghien cuu cho r^ng qua trinh khu protein bing NaOH it tac dong den clu true mach polysacchand cua chitin han so vcri qua trinh khij' khoang bing acid HCI. Do do mu6n giam triet de luang protein ta phai tang nong do NaOH va keo dai thai gian thuy phan Theo nghien cuu cua Lertsutthiwong va cong su (2002), qua trinh khu protein neu thuc hi§n CT nhiet dp phong, n6ng dp NaOH 4% va thai gian 21 h la du de cho san pham chitin cd h^m luang protein con lai thip, x i p xi 1%. Tir ket qua nghien cuu a tren cho phep lua chpn c^c thong s6 thich hap cho qua trinh khii khoang va protein tren dau tom sau khi len men bing NaOH duac trinh bay a bang 3.
Bang 3. Thong so thich hp'p cho qua trinh khCI' khoang va protein con lai o- vo dau torn b i n g NaOH 4%
STT 1 2 3
*
Yeu to Nong do NaOH Thai gian Nhiet dp
Ty le dau tom/dung dich NaOH
Thcngs6t6i^u 4 % 1 3 h Nhiet do phong (khoang 30<'C)
1/4 (w/v) IV KET LUAN VA KIEN NGHI
I. Ket luan
Tu kel qua nghien cuu 6 tren cho phep rut ra mot so ket luan nhu sau
- Hai chung vi khuan L plantarum VTCC 431 va L buigancus VTCC 703 hoan toan CO kha nang khu' khoang va protein a vd dau 16m trong san xult chitin - chitosan Trong dd, Chung vi khuan L plantarum VTCC 431 cd kha nang khu khoang va protein 6 vo diu torn tot hon Chung L buigancus VTCC 703
- Che dd len men khu khoang va protein a vo dau tom thich hop la ti le vi khuan bo sung so voi nguyen heu la 10%. thoi gian len men la 132 h, pH cOa moi truong la 7,2, trong
dieu kien k! khi vai hieu qua khu dup'c hori 85% protein va khoang trong vo diu torn Phan khoang con lai trong vo dau torn se dii'(?c xu' ly tnet d l bing dung dich HC) 4% vai ti I? 5/1 (v/w) trong 17 h va luang protein cdn lai se dup-c xLf ly bing dung dich NaOH 4% vai ti 4/1 (v/w), trong 13h
2. Kien nghi
Tiep tuc nghien cuu cdng doan d hoan thien quy trinh san xult chitiJ Iheo phuang phap smh hoc D o n g I nghien cuu hoan thien qua trinh J va protein a vo dau tom bing f su dung vi khuan cung nhu nghia protein bo sung vao thuc an chaij
' TRUONG DAI HOC NHA TRANG
l^'^-^hLKhMjm^Cmgnohf Tlmv sdn
T.il TIKI TH.4M K H , i o Tieng Viet
: : : » N J " * ' " " " • ^ ' ™ ^ * - ^ " ^ * " " - - . - " . ™„. ,h™ ph^„ V. my ph.„. NXB C o
Urt.sul,hiw„„EP.Chandrk,ach™gS,NazhadM M and Slevcns W F , ™ „ rh ,
for paper. Appi,. Journal 55(3). 208-212 Chilosan as a dry strength agent Kao M. S , Tuven M H 1,,., , n, r
e i . , n , « , e a „ d U e , o b . e i l , : s i r : ™ , * s h r i : ™ : f ' " ' ' : " - " ' ' ™ ° " - °=''">'™"™ ^J " - . " . l e a , . Cl.,l.s.„ in Life Scene., Ya^agnch, C Z p L 301 - "oT™ " " " ° ' = " " " " ' " " " " " " - " " " " » » ' -
-:^^--::zL^tzzi^-^::\'-- - -"•- —- ^^ -™n..on orsi,„,np
80. pp 10811-1087 * " " " " • •'°"""" -rri.ein.cal Technology and Biotechnology.
TRUONG DAI HOC NHA IRANG . 19
