Gvhd :Ths ng Th Ngc Dung
Ha Sinh Thc phm
LI M UNgy nay, cng vi s pht trin mnh m ca cng ngh sinh hc, cc ch
phm enzyme c sn xut cng nhiu v c s dng trong hu ht trong cc lnh vc
nh: ch bin thc phm, nng nghip, chn nui, y t Hng nm lng enzyme c sn
xut trn th gii t khong trn 300.000 tn vi gi tr trn 500 triu USD, c
phn phi trong cc lnh vc khc nhau. . Phn ln enzyme c sn xut quy m
cng nghip u thuc loi enzyme n cu t, xc tc cho phn ng phn hy. Khong
75% ch phm l enzyme thy phn c s dng cho vic thy phn c cht t nhin .
Protease l enzyme c s dng nhiu nht hin nay trong mt s ngnh sn xut
nh: ch bin thc phm (ng t sa lm pho mat, lm mm tht, b sung lm tng
cht lng sn phm trong sn xut bia, x l ph ph phm trong ch bin thc
phm), sn xut cht ty ra, thuc da, y t, nng nghip Qua nhiu nm, vic
gia tng s dng vi sinh vt nh l mt ngun cung cp protease ci thin ng k
hiu qu sn xut v sn phm c to ra nhiu hn. Tuy nhin gi thnh ch phm
protease cn kh cao, do cng
Cc phng php tinh sch enzyme
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Gvhd :Ths ng Th Ngc Dung
Ha Sinh Thc phm
hn ch vic s dng rng ri enzyme trong san xut. Cc ch phm thu c sau
qu trnh nui cy sn xut enzyme cha phi l ch phm c tinh khit cao v
protein ch chim 20-30% .V vy, vic nghin cu ci tin phng php tch v
tinh ch enzyme nhm thu c ch phm c tinh khit cao rt cn thit. tch v
tinh ch enzyme ni ring v protein ni chung thng c mt lot phng php
ha-l v ha hc khc nhau. C th chia lm nm nhm phng php sau: - Phng php
bin tnh chn lc - Phng php kt ta phn an - Phng php hp th chn lc -
Phng php sc k - Phng php tch h hai pha nc Cho n nay khng c phng php
tch v lm sch chung cho cc enzyme. xy dng phng php tch v lm sch mt
enzyme no d cn bit la chn v phi hp mt cch c hiu qu nht cc bin php
tch v lm sch khc nhau.
PHN I: TNG QUANCc phng php tinh sch enzyme 2
Gvhd :Ths ng Th Ngc Dung
Ha Sinh Thc phm
I/Khi nim enzyme - Enzyme l nhng protein c kh nng xc tc cho cc
phn ng ho hc vi mc c hiu khc nhau nhit tng i thp. - Enzyme c trong
tt c cc t bo sng, l cc cht xc tc sinh hc. - Enzyme c y cc tnh cht
ca cht xc tc, nhng enzyme c hiu sut xc tc ln hn tt c cc cht xc tc
hu c v v c khc.Enzyme khng nhng c th xc tc cho cc phn ng xy ra
trong c th sng, m sau khi tch khi h thng sng, nhng iu kin nht nh
chng vn gi c hot tnh xc tc. Nh vy,c th ni mt cch khi qut, enzyme l
nhng phn t ln tn ti trong t nhin, hay c tng hp c kh nng xc tc cho
mt hay nhiu phn ng vi mc c hiu khc nhau nhit v p sut bnh thng.
II/Nhng tiu chun tinh sch ca enzyme xc nh xem protein c chit tch ra
c phi l enzyme tinh khit khng hay cn cha nhng tp cht protein khng
hat ng, ngi ta s dng mt s phng php ch yu da trn vic nghin cu nhng
tnh cht vt l ca protein.
Cc phng php tinh sch enzyme
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Gvhd :Ths ng Th Ngc Dung -
Ha Sinh Thc phm
Lm lng (kt ta) dung dch protein trong phn quay phn tch ca
my siu ly tm: pht hin mt nh ca protein th l protein thun nht.
Tuy nhin mt s protein tuy khc nhau nhng c cng trng lng phn t v c
hnh dng tiu phn ( hoc c khi c s b ph ca cc nh hng ca khi lng v hnh
dng) th c hng s lng trng nhau. V th khi siu ly tm, chng c th lng vi
tc nh nhau v cho mt nh chung.-
in li ( phng php ranh gii di ng): phng php ny rt hiu
qu. Tuy nhin kh m phn bit c nhng protein ging nhau v tr s di ng
in li. Dung dch enzyme khi c in li khu vc trong jela tinh bt hoc
thch ch ra mt nh cn i th l du hiu ca enzyme thun nht. Th nhng khi
hm lng nhng protein tp nh(
