D~I HOC Quac GIA TP.HO CHi MINH
TRUONGD~I HOC KHOAHOCTV NHIEN

YO NGOC B{n
NGHIEN CUU QUA TRINH THUY PHAN PROTEIN CA BANG
ENZYME PROTEASE TU B.5UBTILI5 55
Chuyen nganh: Hml sinh
Mil s6: 1.05.10
TOM TAT LU!N ANTIEN si SINHHOC
THANHPHO HO CHI MINH-2004
Cong tr'inh du(jc hoan thanh t~i:
Tntong D<;tihQc Khoa hQc Tif nhien TP. H6 Chi Minh va Truong
D<;tihQcThuy san Nha Trang.
NguOi huang daD khoa hQc:
1. PGS.TS. D6ng Thi Thanh Thu
Truong Dc~lihQc Khoa hQc Tif nhien, D<;ti hQc Qu6c gla
TP.HCM
2. PGS. TS. Tr~n Thi Luye'n
Truong D<;tihQc ThUy san Nha Trang.
Philo bi~n 1: GS.TSKH. Nguy~n Van Thoa
Philo bi~n 2: GS.TSKH. Nguy~n TrQngC~n
Philo bi~n 3: PGS.TSKH. Ngo Ke'Sudng
Lu~n an dii du<;1cbao v~ truoc HQid6ng cha'm lu~n an ca'p Nha
nuoc hQp t<;tiTruong D<;tihQc Khoa hQc Tif nhien -D<;tihQc Qu6c gia
TP. H6 Chi Minh
Vao h6i 9 gio 00 ngay 15 thang 10Dam2004
Co th~ HIDhi~u luij.nan t~i:
Thu vi~n Truong D<;tihQc Khoa hQcTif nhien
- DHQGTP.HCM
ho<\icthu vi~n Khoa hQcT6ng h<;1pTP.HCM.
1

commersonii).
2
3. D6i tu(jng va ph~m vi nghien CUll
3.1. D6i tu(jng nghien CUll
B.subtilis 55 la chUngvi khu~n co kha nang san xua'tprotease voi ho1;tt
tinh cao du<Jcphan l~p ttt ttf nhien. Ca m6i thuC1ng(5aurida tumbil) va ca
cdm thuC1ng(5tolephorus commersonii) du<Jcdaub bift t1;tivung bi€n
Khanh Hoa.
3.2. Ph~m vi nghien CUll:g6m 3 phh
1) Nghien cUuthu nMn che' ph~m protease ttt canh truC1ngnuoi ca'y vi
khu~n B.subtilis 55 va xac dinh m(}tso'd~c tinh cua enzyme nay.
2) Nghien cUuung d\mg protease B.subtilis 55 vao san xua't b(}td1;tm
thuy phan ttt ca m6i thuC1ng(5aurida tumbil).
3) Nghien CUu qua trlnh thUy phan ca cdm thuC1ng(5tolephorus
commersonii) b~ng protease B.subtilis 55 va d~ xua't huang ung d\mg
enzyme nay trong che' bie'n nuoc mifm.
4. Phudng phap nghien CUll
Lu~n an sil'd\mg cac phudng phap nghien CUucd ban cua Hoa sinh
hQc co stf h6 tr<Jcua cac 19thuye't loan hQCd€ phat hi~n ra cac tinh cha't
moi, cac m6i quail M gifi'acac d1;tilu<Jngva ki€m chung cac gia thuye't.
5. Cac dong gop mdi v~ mijt khoa hQc
-L~n dh lien nghien cUu m(}tcach hoan chlnh v~ cac d~c tinh cua
protease du<Jcsan xua't ttt chUng B.subtilis 55 phan l~p t1;tiVi~t Nam. Ke't
qua cua lu~n an gap ph~n lam phong phu them nhfi'ng hi€u bie't v~
protease ttt vi khu~n B.subtilis 55. .
- Dffnghien CUllsil'd\mg che' ph~m protease ttt B.subtilis 55 trong thuy
phan thit ca m6i d€ san xua't b(}td1;tmthuy phan. Ke't qua nghien CUucua
lu~n an khi du<Jcap d\mg trong san xua't se gap ph~n vao chudng trlnh
"chi biln cae san phdm co giLltrj gia tang" m(}ttrong b6n chudng trlnh
Ion cua B(}ThUysan.

phep co th~ tai sa d\1ngl<;tienzyme nhi€u Mn. Vi v~y ma vi~c ung d\1ng
protease ngay cang gia tang.
d Vi~t Nam cling co nhi€u cong trinh cong b6 v€ vi~c nghien CUllsa
d\1ngprotease cM ye'u t~p trung vao cae protease th\fc v~t va dQng v~t
con protease tit vi sinh v~t mdi chi d11'c,1cnghien CUlltrong hdn ch\1cnam
trd l<;tiday. Vi v~y dn tie'p t\1Ctang c11'angnghien cUu v€ protease tit vi
sinh v~t noi chung va protease tit vi khua'nnoi rieng.
4
'1.2. Gioi thi~u v~ ntioe miim va phtidng phap su' d\mg protease
trong san xua't ntioe miim
Nuoc miim truy~n th6ng Hike't qua cua qua trlnh thuy phan protein thit
ca duoi tac dQngcua M protease nQitl;litrong di~u ki~n co mu6i theo co
che':
protease protease protease
Protein ~ ~ polypeptid .peptid ~ .axit alliin
Ciing voi qua trlnh thiiy phan protein thit ca con co hang lol;ltqua trlnh
bie'n d6i sinh boa sau sAcdo mc dQngcua nhi~t dQva h~ vi sinh v~t co
trong do ma hlnh thanh mall sAc, huang vi d~c tru'ng cua nuoc mAID.
Trong khoang 24 gia d~u tieD, duoi mc dQngcua M protease nQiti;licua
ca ma chUye'u la cac proteinase serine, proteinase kim 10l;liva proteinase
aspartic mQt ph~n protein thit ca bi thuy phan thanh peptid, polypeptid
boa tan trong nuoc b6i (nuoc ca). Sau do protein thit ca, polypeptid va
cac peptid du<;lcti;lothanh d tren Il;litie'p t1;1cbi thuy phan ml;lnhme bdi
cac proteinase kim 10l;litl;lothanh cac axit alliin t1!do, cac peptid ngiin va
da: co s1!hlnh thanh huang vi nuoc mAID.Tit giai dol;ln3 + 6 thang duoi
tac d1;1ngcua cac protease d~c bi~t Ia cac proteinase serine, cac peptid,
cac protein, polypeptid con Il;litie'p t1;1cbi thUy phan tl;lothanh cac axit
amiD t1!do. Khi do chU<;lpda:chin, nuoc mAmnit ra co mall va mlii vi d~e
tru'ng. Ch!t lu<;lngcua nuoe mAm ph1;1thuQe vao 10l;liea, t)11~mu6i sii'
d1;1ng,pH, nhi~t dQ,phudng phap ehe' bie'n Trongqua trlnh san xu!t ne'u

nhung san phifm co mui vi va mall sAckern nudc mAm san xua't rhea
phuong phap truy~n th6ng. DS khAcphl,lchi~n tuQngnay nguai ta co thS
cho ch~y qua chuQp t6t dS la'y huang. Vi v~y, vi~c nghien cUu san xua't
nudc mAm rhea phuong phap sit dl,lngprotease con dn thie't phai duQc
tie'p tl,lCnghien cUu.
1.3. GiOi thi~o v~ b~t d~m va phu'dng phap su' dvng protease d~
san xoa't b~t d~m thuy phan tit ca
Trong qua trlnh khai thac danh bAt tbUy san d nudc ta, luQng ca t~p
kern gia tri kinh te'thuang chie'm ty tr<;}figIOn.Vi v~y, trong chuang trlnh
"chi biin cac san pMm co gid tri gia tang" cua BQTbUy san co phiin
nghien CUusit dl,lng hQp 19cac ngu6n ca t~p, mQt trong cac huang che'
bie'n do la san xua't bQtd~m tbUyphan. Thl)'ccha't cua qua trinh san xua't
bQt d~m ca b~ng phuong phap sit dl,lngprotease la qua trinh tbUyphan
protein ca t~o ra cac peptid va axit amin dudi tac dQngcua h~ protease
nQit~i va protease b6 sung tit bell ngoai. Trong qua trinh thuy phan thit
ca b~ng protease co nhi~u ye'u to'anh hudng tdi t6c dQthuy phan nhu: ty
l~ enzyme, nhi~t dQ,pH, ty l~ nudc b6 sung Nen yell ch d~t ra la phai
tim ra che'dQ thuy phan thich hQpdS san xua'tra bQtd~m ca d~t yell duo
Chudng 2.VOl TU(1NGvA PHUONGPHAp NGHIEN CUD
2.1. VO'itu'Q'ngnghien CUll
2.1.1. Ngo6n tho nh~n enzyme protease
B.subtilis S5 Ia chung vi khuifn co kha nang san xua't protease vdi ho~t
tinh cao duQc phan l~p tit tl)'nhien va lUll giii' t~i phOng Vi sinh - Vi~n
Sinh hQc Nhi~t ddi TP. H6 Chi Minh. ChUng B.subtilis S5 nay duQc sit
dl,lngdS nghien cUu san xua't protease b~ng phuong phap nuoi ca'y ban
rAn.Sau khi ditng qua trinh nuoi, thu canh trltang chua protease, sa'ykho,
xay min va sit dl,lngdS tach chie't protease.
6
2.1.2. Nguy~n li~u ea d~ san xudt nu'oe miim va bQt d~m
- Ca m6i nguyen li~u: Ca m6i thu'ang (hlnh 2.1) du'<;ledaub bAt t~i

3.1.1. Phuong phap giii'~m thich hQ'p
Thii nghi~m san xua't protease ttt B.subtilis S5 rhea phuong phap nuoi
ea'y ban rAntrong di~u ki~n co thong gio va giG'a"'mrhea 3 phuong phap
nhu san: phuong phap 1: b~ m~t khay nuoi khOng pho vai a"'m;phuong
phap 2: b~ m~t cae khay nuoi duQcphOvai a"'m;phu'ong phap 3: b~ m~t
khay nuoi pho vai a"'mva san 4 giOnuoi phon hoi nude qua may th6i khi
vao phong nuoi d~ t<.10de>a"'m.San 37 gio nuoi, tho canh tru'ong chua
enzyme va xae dinh ho<.1tde>protease. Ke'tqua th~ hi~n d bang 3.1.
Bang 3.1. Anh hudng cua phuong phap giii'~m toi ho~t dQprotease
B.subtilis 55 tho duQ'ctrong canh truong
Phu'ong phap
giG' a"'m
Ho<.1tde>protease
(UI/g canh
tru'ong)
1
20,2
2
21,1
3
28,2
Tr<.1ngthai eoa eanh tru'ong
B~ m~t eanh tru'ong bi thO, nUt,vi
khua"'nmQe trAngphia du'di con d
phia tren thl thong mQc.
Tu'ongtl! nhu'tren
B~ m~t canh tru'ong thOng bi thO,
kh6i canh tru'ong nong, a"'m,m~m,
vi khua"'nmQc trAng cii tren va
du'di.

de'n 55°C, vi khuffn phat tri6n kern,
canh trlfong roi rc.
2
28,6
Nhit dQcanh trlfong nuoi t6i da leu
Wi 45°C, vi khuffn rnQctriing d. teen
va dlfdi, canh trlfong cleodinh.
Th<'1igian
17 21 25 29 33 37
41
45 49 53
(gi<'1)
Hot d(>
5,0 8,0 12,5 17,5 23,5 31,5
33,2
33,1 32,0 29,5
protease (DUg)
9
Nuoc 80% so voi nguyen lieu
BOt blip + kh6 d~u I,!c + cam
gaD
Khming bon h(ip
Giang B.subtilis 55
E>anhwi
1
ffinh 3.1. Sd d6 quy trlnh san xua't protease tt'iB.subtilis 85
* Thuye"tminh quy trlnh
+ Nhan gi6ng B.subtilis 85: gi6ng B.subtilis 85 phan l~p tu tt! nhien
va du'<;1ebaa quan (j 5°C tren moi tru'onggiG'gi6ng co thanh ph~n: agar:
2%, eao thit: 0,5%, peptone: 0,5%, NaCl: 0,25%.

enzyme bhg cae dung djeh: nude efft, dung dieh d~m Britton pH 6, dung
dieh d~m phosphat pH 6 va dung dieh mu6i sinh 1:9.Sau khi ehie't rut ly
tam tho djeh ehie't (DC) enzyme va xae dinh ho~t dQ protease, ke't qua
th€ hi~n (j hinh 3.2.
~
'0 .';:;'
;:,~. 90
" "
:0 ~.
'=' " 60
:-0.<6
;: ~ 30
". ~
0
::r:
11
120
100
%.3
0
.Nudc dlt . f)~m britton GI f)~m phosphat GI Mu6i sinh 19 I Dung djch chi"t enzyme
Hinh 3.2. AOOhuang ena dung dieh ehie't rut de'n ho~t dQprotease
Tli ke't qua hlnh 3.2 cho tha'ynudc ca'tchinh la dung moi thich hQpcho
vi~c chie'trut protease tli B.subtilis S5.
3.2.2. Xae djnh tae nhdn ke't tna protease B.subtilis SS
Tie'n hanh ke't tua protease B.subtilis S5 ra khai DC enzyme b~ng
aceton, ethanol va sulphat amon d cling n6ng de>70%. Sau do ly tam thu
che' ph£m enzyme (CPE), boa tan trong cling me>tth~ tich nudc ca'tva xac
dinh ho~t de>protease. Ke'tqua nghien cUuth~ hi~n d hlnh 3.3.
'0 :::;-120

'i<.
0
:I:
120
100
80
60
40
20
0
100
99,89
93,1
83,5
60 ~ m ~ w
Ndngd~Ethanol(%)
Hinh 3.4. AOOhuang ena n6ng dQethanol de'n ho~t dQprotease CPE
12
Ke't qua a hinh 3.4 cho tha'y ethanol
an6ng dO75% la thich hQpcho
vi~c ke't tua thu protease CPE.
3.2.3. Anh hu'dng cua pH de'n ho~t dQprotease B.subtilis SS
Ke't qua nghien CUuduQcth~ hi~n a hinh 3.5.
L :~L : :
li~ /- ~
0 2 ~ 3 U 4 U 5 U 6 ~ 7 U 8 U 9 ~
I -DC -o-CPE I pH
Hinh 3.5. Anh hu'dng cua pH de'n ho~t dQprotease B.subtilis SS
Ke't qua nghien cUua hinh 3.5 cho tha'ykhoang pH thich hQpcho ho<.tt
dOprotease B.subtilis 55 la 5,5 - 7 va pH t6i thich la 6.

xac dinh ho<.ttdOprotease. Ke'tqua th~ hi~n a hinh 3.7.
13
:g;g 150
~
",,'0
.§~IOO
'=: .D
:;;.;s 50
'0 >
5; 0
o. ~
:r:~ 0 5 10
-
-0
-
=t
.
0
.
t
.
0
.
'9'
. .
0- -0
~ $
15 20 25 30 35
Thai gian xii' 19 (pMt)
- DC65 CPE65I

s6 cha't d~c hi~u nh6m thu'ong co vai tro quan trQng d6i voi hol;ltdQ
protease. Ke'tqua du'ejCth~ hi~n d hlnh 3.9.
0
0
3 5 7 9 11 13 15
14
~ 120
01)
:g <S 100
01) -8 80
c
"0 \0
::: "" 60
~. ~ 40
~. ~ 20
::r::~ 0
~
~
(, ~< x x x x x x x x x x,,>,' '1'
O
t\."-$'
~ -# cP "',;' ~:;: p"i # "lY 0~ 0~ ",-<"'i ~:;: 0"- <i,'Y<' ~'Y o,,>i}~
Cha't them vao ptian ti'ng
Ifmh 3.9. Anh hu'dng cua ion kim lo~i va mQt s6 cha't ~c hi~u
nhom de'n ho~t dQprotease B.subtilis 85
Tu hlnh 3.9 cho tha'y ta't ca cac cha't them vao phan ftng (trir 2-
Mercaptoethanol va L-cystein) d~u lam giam ho;:ttd(>protease CPE va
DC. Cac ion Cuz+,Pbz+,Hgz+,HzOzva EDTA lam giam m;:tnhho;:ttd(>cua
protease CPE va mftc d(>lam giam nhi~u hdn so vdi protease Dc. Trong
khi do 2-Mercaptoethanol va L-cystein l;:ti lam tang r5 r~t ho;:tt d(>

0.8
i;j .g
<I) <=
0.6 <0- ~
"0 ""
0.4 ';;j. ;::;
o.z ~ 2-
0
Philo do~n
Ifmh 3.10. siic ky d6 protease CPE qua cQt IQcgel sephadex G-75
Ke't qua a hlnh 3.10 cho tha'y sau khi qua cQt IQcgel sephadex G-75
thu duQc4 dinh protein theo thftt11qua c(>tla I, II, III, IV. Trong do chi co
15
2 dinh co ho~t dOprotease cM ye'u 1adinh I va II (ki hi~u la P-I va P-II).
P-II co ho~tdO protease chie'm toi 84,3% ho~t dO len cOt va co dOtinh
s~ch ga'p 15l~n so voi protease DC ban dffu(bang 3.4).
Bang 3.4. Tom tiit qua trinh tinh s~ch protease
Sail khi tach protease CPE qua cOt lQcgel, tie'n hanh thu cac phan
do~n co P-I (phan do~n tit 6 - 12) va P-II (phan do~n tit 13 - 24) d~ tie'p
tl,lCnghien CUllmQts6 tinh cha'tcua cac protease nay.
3.2.8. MQt s6 tInh chift cua cae P.I va P.II
3.2.8.1. Anh htidng cua mQt s6 ion kim lo~i hoa trf 2 va mQt s6 chift
d~c hi~u nhom tOiho~t dQP-I va P-II
Ke't qua nghien CUllth~ hi~n d hinh 3.11.
~ 250
55 200
""
,":::00 150
;g <§
"" -5 100

DC
192,55 8,28
100,00
0,043
1,0
CPE
21,33
6,63
80,07
0,311
7,2
P- I
1,48 0,18 2,17
0,122
2,8
P- II
8,69 5,59 67,51 0,643
15,0
16
ho<:ttdQP-II; trong d6 Hg2+,H2O2va EDTA uc che' m<:tnhme ho<:ttdQP-II
va lam giam tu'dng ung tdi 100%,97,9% va 98,6% ho<:ttdQP-II. D~c tinh
nay kern theo kha nang du'<;1cho<:tthoa du'ditac d\mg cua cac chtt khii'2-
Mercaptoethanol va L-Cystein (2-Mercaptoethanol va L-Cystein lam
tang tdi 200%va 189,7%ho<:ttdQP-II) la OOungtinhchtt d~ctru'ngcua
protease c6 chua nh6m thiol (-SH) trong trung tam ho<:ttdQng cua
enzyme. Ke't qua nay chung to P-II thuQc nh6m proteinase thiol
(proteinase cystein) theo cach phan lo<:ticua Hartley.
D~ tie'p h,lCtlm hi~u v~ d~c tinh cua P-II, till nghi~m tie'nhaOOxii'19P-
II b~ng EDTA vdi n6ng dQtrong h6n h<jpla 6 x 10.3M(j 30°C trong thai
gian 10 phut. Sau khi xii' 19 tai ho<:tt hoa enzyme b~ng: 2-

3.2.8.2. Anh htidng cua pH va nhi~t dQde'n ho~t dQP-II
Do P-II 1a dinh ho<;ltdOprotease chinh khi tach protease CPE qua cOt
1Qcgel sephadex G-75 nen tie'p tt;lcnghien CUllky hdn v€ protease nay.
Ke't qua nghien CUllcho tha'y P-II co pH thich h<jp6,0 va nhi~t dOthich
h<jp60°c.
3.2.9. Nghien cUu bao qUail protease CPE cua B.subtilis S5
Tie'n hanh nghien CUllbaa qUail protease CPE CJ4°C cho tha'y hoan
roan co thS bao qUail protease CPE cua B.subtilis S5 CJd<;ingdong kho
ho~c boa tan trong dung dich sorbitol co n6ng dOtren 10%. Ke't qua nay
mCJra mOthuang san xua'tprotease B.subtilis S5 duai d<;lngdich long ra't
ti~n l<jicho vi~c ung dt;lngtrong tht!c te'san xua't.
3.3. Nghien cuu qua trinh thuy phdn thjt ca m6i biing protease
B.subtilis S5 va san xuilt bQt d~m
3.3.1. Thanh ph§n boa hQccua ca m6i
Ke't qua xac dinh sd bOthanh phftn kh6i lu<jngcua ca m6i daub bAt
vao thang muCfiCJvung biSn Khanh Hoa dti<jctrlnh bay CJbang 3.5.
Bang 3.5. Thanh ph§n kh6i lti(/ng cua ca m6i (%)
Thit ca fillet
f)~uca
Xudngca Yayvavffy
NOit<;lng
56,23 18,46 13,69 5,64 5,98
Ke't qua phan rich cho tha'y ca m6i co ty l~ ph~n an du<jckha cao
(56,23%), ham lu<jngprotein t6ng s6 cao (19,7%) va ham lu<jnglipid tha'p
(1,4%) Den xe'p vito IO<;lica g~y ra't thich h<jpcho vi~c san xua't bOtd<;lm
va dam bao bOtd<;lmthanh phffm it bi oxy boa bCJilipid. Ngoai ra ke't qua
phan rich thanh ph~n axit amiDcua thit ca m6i con cho tha'y thit ca chua
kha d~y du cac axit amin thay the'va khong thay the'. Vi v~y, ca m6i la
d6i tu<jngdn du<jcnghien CUlldS san xua't thanh bOt d<;lmb6 sung vito
bOtdinh du6ng cho nguCfi.

ea m6i biing protease B.subtilis 55
Ke't qua nghien CUlleho tha'y b6 sung 3% mu6i an vao qua trlnh thuy
phan thit ca m6i b~ng protease B.subtilis S5 1athich h<;1pcho vi~c uc che'
19
vi sinh v~t gay thoi ma v~n dam baa eho qua trlnh thuy phan di~n ra
m~nh.
3.3.2.6. Anh htfdng eua ty I~ ethanol tOj qua tdnh thuy philo thit
ea m6i biing protease B.subtilis 55
Cae ke't qua phan tich eho tha'yb6 sung 8% ethanol VaGh6n heJpthuy
philo thit ca moi bAngprotease B.subtilis 55 la thleh heJpeho vi~e lie ehe'
vi sinh v~t gay thoi ma vh dam bao eho qua trlnh thuy philo di~n ra
m~nh.
3.3.2.7. Anh htfdng eua ty I~ sorbitol t8i qua tdnh thuy phan thit
ea m6i biing protease B.subtilis 55
Ke't qua thi nghi~m eho tha'y d~ lie ehe' ho~t di)ng eua vi sinh v~t gay
thoi trong qua tdnh thuy philo thit ca m6i b~ng protease B.subtilis 55 co
th~ b6 sung sorbitol vdi ty l~ 4%.
3.3.2.8. Dng d\mg protease B.subtilis 55 d~ san xua't bQt d~m tit ea
m6i
* Xae dinh thOi gian thleh hqp eho vi~e ue ehe'vi sinh v~t gay th6i
dieh thuy philo biing mu6i an, ethanol va sorbitol
Ke't qua cho tha'y doi vdi cae m~u b6 sung mu6i an 3% va b6 sung
sorbitol 4% san 16 giC1thuy philo co hi~n tueJngbi hu hOng bi~u hi~n la
ham lueJngpeptid, Naat~o thanh Mt d~u giam con ham lueJngNNH3t~o
tMnh beltd~u tang cao. VI v~y doi vdi hai m~u nay phiii dung qua trlnh
thuy philo (Jgiai dol,ln16giC1.Con mh b6 sung 8% ethanol thl san 18 giC1
tbUyphilo m~u nay beltd~u co hi~n tueJngbi hu hong. Do v~y, phiii dung
qua trlnh thuy philo (Jgiai dol,lnnay.
* San xua't thii' bQt d~m tit thit ea m6i
Thii'nghi~m thii'san xua't bi)t d~m theo cae thOng sO'tlm dueJe(Jtren.

Ve't Ve't
SIT
Ten chi lieu xet nghim
Ke't qua
1
T6ng so'vi sinh vt hie'u khf Ig
6,8.102
2 Escherichia coli
Am tfnh
3
Staphylococcus aureus
Am dnh
4
Salmonella Am tfnh
5
Clostridium perfringens
0
21
Bang 3.8. Thanh ph~n axit alliin tll do cua bc}td~m tit ca m6i
3.3.2.9. D~ xua't quy trlnh san xua't bc}td~m thuy philn tit ca m6i
Tit cae ke't qua nghien cU'ud tren cho phep rut ra quy trlnh san xua't
bQt d~m tMy phan tit thit ca m6i thu'C1ng(Saurida tumbil) bhg protease
B.subtilis S5 du'<;1cth€ hit;n tren hlnh 3.13.
STT
Ten axit amin
Ham 1u'<Jng(g/g bQtdm)
1
Alanine
10.241,0
2

Glutamic axil
4.563,0
15
Ornithine
2.830,0
16
Lysine
31.900,0
17
Histidine
6.269,0
18
Tyrosine
108.513,0
19
Tryptophan
1.553,0
20
T6ng cc}ng
236.139,0
B6 sung nude
I
B6 sung CPE
Bii
H Thi1can gia sue I
I Nghi~n mjn I
.
I Bao g6i bao qmin I
Hinh 3.13. Quy trinh san xua't bQt d~m tit ca mo'i
* Thuye't minh quy trinh

23
-Dun soi: ke't thuc qua trinh thuy phan dun soi trong 15 phut d~ vo
hoi;ltenzyme va die:;tvi sinh v~t.
- LQc: d~ 10i;libOph~n xuong, vay, vay con Ifilltrong h6n hc;fP.
- Ly Him tach ma: tach miJ co trong san ph~m nhAm hi;lnche' qua
trinh oxy boa lipid d~n de'n vie:;cbie'n mh, mui va lam giam chfft 1uc;fng
cua bQt di;lmthanh ph~m. Ly tam tach miJ bAngmay 1ytam 1i;lnhvoi t6c
dQ 7000 vong/phUt trong 15 phUt. Sau khi Iy tam IOi;libO lOpmiJ tren b~
m~t va tach thu ph~n dich thUyphan. Sau do co d~c bAngphuong phap co
quay chan khOng, sffykhOd nhie:;tdQ70°C, nghi~n nhO,baa goi bQtdi;lm
thanh ph~m bAngtui PE trong di~u kie:;nchan khong d~ bao quan.
3.4. Sd' d1)ngprotease B.subtilis 85 trong san xua't mfoc miim
3.4.1. Thanh phdn boa hQccua ca cdm
Thanh phffn boa hQCco ban cua ca com duc;fcth~ hie:;nd bang 3.9.
Bang 3.9. Thanh phdn boa hQc cd ban cua ca cdm (%)
Ke't qua nghien CUllcho thffyca com co ham Iuc;fngprotein kha cao toi
18,7% va ham Iuc;fnglipid thffp. Ngoai ra khi phan tich thanh ph~n axil
amin cua ca com con cho thffy ca com co kha d~y du va can d6i axil
amino Chinh VIthe' ca com la d6i tuc;fngthich hc;fpcho vie:;csan xufft nuoc
mcim.
3.4.2. Xac dinh di~u ki~n thfch hqp cho qua trinh thuy philo ca
cdm bhng protease B.subtilis 85
3.4.2.1.Xac dinh ty I~ CPE thfch h«jpcho qua trinh thuy phdn
Ke't qua nghien CUllthUyphan ca com bAngprotease B.subtilis 55 voi
cae ty Ie:;CPE b6 sung khae nhau cho thffy ty Ie:;protease CPE thich hc;fP
b6 sung vao qua trinh thUyphan ea com Ia 0,2%.
Nuoc
Protein
Lipid Khoang
NNH3 NTs