nghiên cứu quá trình lên men

7/24/2019 Nghin Cu Qu Trnh Ln Men

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BGIO DC V O TO

I HC NNG

PHM THTHY TRANG

NGHIN CU QU TRNH LN MENAXIT GLUCONIC TRNG

BNGASPERGILLUS NIGER

Chuyn ngnh: Cng nghThc phm v ung

M s: 60.54.02

TM TT LUN VN THC SKTHUT

Nng,Nm 2012

2

Cng trnh c hon thnh ti

I HC NNG

Ngi hng dn khoa hc: PGS. TS. ng Minh Nht

Phn bin 1: GS. TS. o Hng Cng

Phn bin 2: PGS. TS. L ThLin Thanh

Lun vn c bo vtrc Hi ng chm Lun vn tt nghipthc s kthut hp ti i hc Nng vo ngy 17 thng 11 nm

2012.

C thtm hiu lun vn ti:

Trung tm Thng tin-Hc liu, i hc Nng

Trung tm Hc liu, i hc Nng


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chc ngha vkinh tm cn mra khnng gii quyt cc vn

vcht lng sn phm, cc vn vgii php kthut mt cch

hiu qu2. MC TIU NGHIN CU

- Xc nh cc thng scng nghtt nht nh: tlging,

thi gian ln men, hm lng nitbsung trong qu trnh ln men.

- xut quy trnh k thut ln men axit gluconic t r

ng bng chng nm mcA. niger.

3. I TNG V PHM VI NGHIN CU

- S dng r ng c thu nhn cng ty ng Kon

Tum ti Km 2, x Vinh Quang, Thnh phKon Tum, tnh Kon Tum.

-Chng nm mc A. niger ti phng th nghim khoa Ha,

trng i hc Bch Khoa, i hc Nng.

- Nghin cu ln men axit gluconic t rng bng chng

nm mcA. nigerqui m phng th nghim (PTN).

4. PHNG PHP NGHIN CU

- Phng php vt l:

Xc nh nng cht kh bng Bx k

- Phng php ha hc:

Xc nh hm lng ng khbng phng php Bectran

Xc nh hm lng nittng bng phng php kjehldal.

- Phng php ha l:

Xc nh pH rng v pH ca mi trng nui cy trc v

sau ln men

Xc nh axit gluconic bng my sc k lng hiu nng

- Phng php vi sinh:

Phng php hot ha ging

Phng php ln men chm.

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- Phng php ton hc:

Sdng quy hoch thc nghim ton phn 3 yu tkho

st nh hng ca cc yu tthnh phn n hm lng axit gluconic.Sdng phng php leo dc ti u ha cc yu tnh

hng.

5. NGHA KHOA HC CA TI

- Xc nh mt sthnh phn ha hc trong rng v hm

lng axit gluconic bng cc phng php (PP) phn tch hin i.

- Xc nh iu kin ln men tt nht thu c hm lng

axit gluconic cao nht.

- Xy dng c quy trnh ln men gluconic t rng

quy m PTN.

6. NGHA THC TIN CA TI

- Nghin cu ny gip s dng phphm ca qu trnh

sn xut ng to ra ngun nguyn liu chnh sn xut axit

gluconic, mang li li ch kinh tcho cc nh sn xut ng.

- Gim lng axit gluconic ngoi nhp, chng sn xut.

- M rng ng dng cng ngh sinh hc trong cng ngh

thc phm v mt slnh vc khc.

7. CU TRC LUN VN

Ngoi phn mu, kt lun, ti liu tham kho v phlc,

trong lun vn gm c cc chng nhsau :

Chng 1: Tng quan

Chng 2: i tng v phng php nghin cu

Chng 3: Kt quv tho lun


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CHNG 1

TNG QUAN

1.1. AXIT GLUCONIC1.1.1.Gii thiu vaxit gluconic

Axit gluconic l mt axit hu c yu, c tnh st khun,

khng bay hi, khng c, khng c tnh n mn, c ngun gc t-

D-glucose to thnh bi mt phn ng oxy ha di xc tc ca

enzym glucose oxidase. Axit gluconic c mt tnhin trong cc loi

qu, mt ong, tr kombucha (nm hng tr) v ru vang.

Trong cng nghip thc phm axit gluconic c s dng

nhmt cht iu v, n c khnng to ra hng vchua du nhv

c sdng nhmt phgia iu chnh vchua (E574) dng cho

cc sn phm nhru vang, nc p tri cy, sa chua,.

Tn khoa hc:

(2R,3S,4R,5R)-2,3,4,5,6-pentahyroxyhexanoic axit

1.1.2. Cu to ca axit gluconic

Axit gluconic l mt hp cht hu cc cng thc phn tl

C6H12O7, cng thc cu to l:

Hnh 1.1. Cu to hn taxit luconic

8

Axit gluconic c cu trc ho hc bao gm mt chui su

cacbon vi nm nhm hydroxyl v kt thc bng mt nhm chc

cacboxyl (-COOH). Trong dung dch nc nng 1/1000 axitcacboxylic pH gn trung tnh, axit cacboxylic ny to ra cc ion

gluconat v cc mui ca axit gluconic gi chung l cc gluconat.

Khi ha tan trong nc axit nhanh chng chuyn sang trng thi cn

bng ng vi vng glucono--lacton, lm cho dung dch tr thnh

hn hp ca axit vi glucono--lacton.

1.1.3. Tnh cht ca axit gluconic v mui gluconat

1.1.4. Lch spht trinaxit gluconic

1.1.5. ng dng ca axit gluconic v mui gluconat

1.1.6. Sn xut axit gluconic v mui gluconat

1.1.6.1. Sn xut axit gluconic tenzyme glucose oxidase

1.1.6.2. Sn xut axit gluconic tvi khun

1.1.6.3. Sn xut axit gluconic tA. niger v Penicillium luteum

Axit gluconic

Hnh 1.2. Schuyn ha glucose thnh axit gluconic bi A. niger

C6H12O6+ H2O + O2C6H12O7+ H2O2


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1.2. CSQU TRNH LN MEN AXIT GLUCONIC

1.2.1. Gii thiu vAspergillus niger

1.2.2. Cc phng php ln men1.2.2.1. Phng php ln men bmt

1.2.2.2. Phng php ln men bsu

1.2.3. Ssinh trng v pht trin ca vi sinh vt trong iu kin

nui cy tnh

1.2.3.1. Pha mu (pha tim pht)

1.2.3.2. Pha logarit (pha ly tin)

1.2.3.3. Pha n nh (pha cn bng)

1.2.3.4. Pha tvong

1.2.4. Cc yu tnh hng n qu trnh ln men axit gluconic

1.2.4.1.nh hng ca cacbon

1.2.4.2.nh hng ca nit

1.2.4.3.nh hng ca thi gian

1.2.4.4.nh hng ca oxy

1.2.4.5.nh hng ca nhit

1.2.4.6.nh hng ca PH

1.2.4.7.nh hng ca tlging

1.3. NGUYN LIU RNG

1.3.1. Gii thiu nguyn liu rng

1.3.2. Mc ch ca xl rng trc khi ln men1.4. TNH HNH NGHIN CU AXIT GLUCONIC VIT

NAM V TRN THGII

1.4.1. Cc cng trnh nghin cu trong nc

1.4.2. Cc cng trnh nghin cu nc ngoi

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CHNG 2

I TNG V PHNG PHP NGHIN CU

2.1. I TNG NGHIN CU2.1.1. Rng

R ng ly t cng ty ng Kon Tum v c x l

trong phng th nghim trc khi ln men. Rng c pha long

vi tlrng:nc l 2:1 kg/kg, tin hnh xl nhit 85-90oC

trong thi gian 45-60 pht, iu kin ny hu ht cc tp khun u

btiu dit. Sau khi xl nhit tin hnh ly tm nguyn liu 8oC, tc

5500 vng/pht, thi gian 30 pht, tch cc cht khng ha tan v

cc cht keo ra khi rng. Kt thc qu trnh xl rng c

bo qun 4oC.

2.1.2. Chng vi sinh vt

Chng nm mc A. niger c nui cy v gi ging ti

PTN khoa Ha, trng i hc Bch Khoa, i hc Nng.

2.2. HA CHT V THIT B

2.2.1. Ha cht

2.2.2. Thit b

2.3. PHNG PHP NGHIN CU

2.3.1. Phng php vt l

2.3.2. Phng php ha l

2.3.3. Phng php ha hc2.3.4. Phng php vi sinh

2.3.5 Phng php ton hc


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CHNG 3

KT QUV THO LUN

3.1. KHO ST THNH PHN HA HC CA RNGBng 3.1. Kt qukho st thnh phn ha hc ca rng

Thnh phn Gi tr

Bx 84.41

pH 5.40

Protein 3.64 (% cht kh)

ng kh 22.70 (% khi lng)ng tng 54.50 (% khi lng)

ng saccarose 30.21 (% khi lng)

3.2. NGHIN CU LA CHN PHNG PHP LN MEN

AXIT GLUCONIC

Bng 3.2. Kt qunghin cu la chn phng php ln men axit gluconic

Thng s Phng php cnhnm mcA. niger

Phng phpkhng cnh

nm mcA. niger

Chun b

ln men

Xl xda, cnh

nm mc 20 gi

trong iu kin tnh

Hot ha nm mc

trn my lc 20 gi

Xl sau

ln men Lc p chn khng Lc tch b

Vdch ln men

(ml/100ml)50 ml 75 ml

Chiu cao

peak (mAU)266.95 380.26

Axit gluconic 2.53 3.59

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(g/100ml)

Sc k

Nhvy, trong iu kin c cnh nm mc ln men axit

gluconic trn my lc, do scn trca cht mang oxy kh ha tan,

qu trnh ln men din ra chm, thi gian ln men ko di to sn

phm ph. Ln men trong mi trng lng trn my lc to iu kincho oxy tip xc ccht, qu trnh ln men din ra trong ton bkhi

dch ln men, thi gian ln men ngn, hiu sut ln men cao. Tkt

qutrn, chng ti la chn phng php ln men trong mi trng

lng trn my lc lm phng php nghin cu ca mnh.

3.3. NGHIN CU XY DNG PHNG PHP XC NH

HM LNG AXIT GLUCONIC BNG MY HPLC3.3.1. Nghin cu xy dng ng chun HPLC cho axit gluconic

3.3.1.1. Nghin cu tlpha ng khi cnh pH mu phn tch 7.0

Bng 3.3. Nghin cu tlpha ng khi cnh pH mu phn tch 7.0Tn quy

trnhTlpha ng

pH mu

phn tchthnh tnh

1 Acetonitrile:nc3:7 (v/v)

pH = 7.0.

2Acetonitrile:nc

7:3 (v/v)

pH = 7.0.

3Acetonitrile

100%

pH = 7.0.


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Da vo kt quphn tch cho thy sc k c hnh dng

phc tp. Khi sdng NaOH tinh khit iu chnh pH mu phn

tch 7.0, lc ny mu phn tch tn ti 3 hp cht (axit gluconic,glucono--lacton, mui gluconat), do trong dung dch tn ti h

bin gia 2 dng ng phn ny. Thay i tlpha ng chlm thay

i schuyn ha gia cc cht, cht no tn ti nhiu nht cho hnh

dng peak cao nht. Kt qusc k tn ti nhiu peak phc tp.

3.3.1.2. Nghin cu tlpha ng khi cnh pH mu phn tch 2.5

Bng 3.4. Nghin cu tlpha ng khi cnh pH mu phn tch 2.5

Tn quy

trnhTlpha ng

pH mu

phn tchthnh tnh

1Acetonitrile:nc

3:7 (v/v)pH = 2.5

2Acetonitrile:nc

7:3 (v/v)

pH = 2.5.

3Acetonitrile

100%

pH = 2.5

Khi c nh pH mu phn tch 2.5 v mt l thuyt axit

gluconic tn ti dng mch thng. Tuy nhin, do pha ng c pH

trung tnh, hiu qupha long pha ng nh hng ln n pH ca

mu khi i qua ct lm ti xc lp cn bng gia 2 dng ng phn.

Axit gluconic nhanh chng chuyn sang trng thi cn bng vi vng

glucono--lacton. Khi thay i tlpha ng chlm thay i tl

gia axit gluconic v glucono--lacton. Khi mu qua ct trn sc k

xut hin 2 peak tng i r.

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3.3.1.3. Nghin cu pH pha ng khi cnh pH mu phn tch 2.5

Chng ti tin hnh iu chnh pH pha ng 2.5, bng cch

bsung H3PO4vo nc ca pha ng tlaxit H3PO4:nc(1:1000v/v), tlpha ng acetonitrile:nc (3:7 v/v). Trong iu kin ny

ch xut hin 1 peak duy nht. Nh vy, trong mi trng H+

glucono--lacton mvng chuyn ha vaxit gluconic, lc ny dung

dch i qua ct l axit gluconic ng nht, trn sc k cho duy

nht 1 peak. Kt qunghin cu thhin bng 3.5.

Bng 3.5. Nghin cu pH pha ng khi cnh pH mu phn tch 2.5

thnh tnh Cchchuyn ha

glucono--lacton

thnh axit gluconic

Nh vy, chng ti xy dng c quy trnh phn tch axit

gluconic nhsau pha tnh l ct C18, tc dng 0.5 ml/pht, bc

sng 210 nm, tlpha ng: acetonitrile:nc (3:7 v/v), pHnc= 2.5.

3.3.1.4. Xy dng ng chun axit gluconic

Hnh 3.1.ng chun axit gluconic


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gim. Kt qutlging bsung l 10% vi mt bo t106-107

bo t/ml thu c kt qutt nht l 30.24 g/100g mt r.

3.4.3. nh hng ca thi gian ln men n hm lng axit gluconic

Qua quan st hnh 3.5 cho thy ban u khi thi gian ln men

tng, hm lng axit gluconic sinh ra tng, khi thi gian ln men ko

di hm lng axit gluconic gim. Thi gian u nm mc sdng

ccht tng sinh khi, ng thi tit enzyme chuyn ha cc

cht. Khi lng tbo cng ln th lng enzyme tit ra cng nhiu,

lng axit gluconic sinh ra cng tng theo thi gian. thi im 96

gi qun th vi sinh vt bc vo pha cn bng hm lng axit

gluconic sinh ra ln nht. Nu tip tc ko di thi gian ln men, khi

ngun dinh dng cn kit cng vi sn phm axit gluconic to ranhiu sc ch spht trin ca vi sinh vt. Nm mc bt u s

dng sn phm sinh ra lm ccht, to ra cc sn phm phgy tn

tht sn phm chnh ng thi gy kh khn cho qu trnh tinh sch

sn phm. Kt qu sau 96 gi hm lng axit gluconic ln nht l

30.81 g/100g mt r.

Hnh 3.5.nh hng thi gian ln men n hm lng axit gluconic

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3.4.4. nh hng ca hm lng nit b sung n hm lng

axit gluconic

Qua nghin cu nh hng ca hm lng nitbsung n

hm lng axit gluconic to thnh, da vo thhnh 3.6 cho thy

ngun nit c sn trong nguyn liu khng m bo cho qu trnh

sinh trng pht trin ca vi sinh vt. Trong giai on u khi hm

lng nitbsung tng hm lng axit tng ln r rt, t gi trcao

nht 29.18 g/100g mt rvi hm lng (NH4)2HPO43 g/l. Tip tc

tng hm lng (NH4)2HPO4, khi hm lng nitqu cao dn n

lng sinh khi to ra ngy cng nhiu, xy ra hin tng cnh tranh

dinh dng nh hng n hiu sut ln men. Hm lng axitgluconic sinh ra gim dn v thp nht 23.97 g/100g mt rkhi hm

lng (NH4)2HPO45 g/l. Kt quhm lng axit gluconic to thnh

ln nht l 29.18 g/100g mt rkhi hm lng (NH4)2HPO4 bsung

l 3 g/l,

3.5. NGHIN CU NH HNG NG THI CA BA YU

TN QU TRNH LN MEN AXIT GLUCONIC

Hnh 3.6.nh hng hm lng nitbsung

n hm lng axit gluconic


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3.5.1. Chn yu tnh hng

3.5.2. Chn iu kin th nghim

Y = b0+ b1x1+ b2x2 + b3x3 + b12x1x2 + b13x1x3+ b23x2x3 + b123x1x2x3(3.2)Bng 3.8. Cc iu kin th nghim

Cc mc

Mc di Mc cs Mc trnYu t

-1 0 +1

Khong

bin thin

Z1 8 10 12 2

Z2

84 96 108 12

Z3 2 3 4 1

3.5.3. Tchc v thc hin cc th nghim

Bng 3.9: Kt quth nghim quy hoch nhn tton phn 23

Cc nhn ttheo t

lxch tnhinCc nhn ttrong htokhng thnguyn

TT Z1 Z2 Z3 x1 x2 x3 x1x2 x1x3 x2x3 x1x2x3 y

1 8 84 2 - - - + + + - 22.90

2 12 84 2 + - - - - + + 24.42

3 8 108 2 - + - - + - + 28.97

4 12 108 2 + + - + - - - 23.76

5 8 84 4 - - + + - - + 26.95

6 12 84 4 + - + - + - - 27.29

7 8 108 4 - + + - - + - 33.38

8 12 108 4 + + + + + + + 28.55

T1 10 96 3 0 0 0 0 0 0 0 33.69

20

T2 10 96 3 0 0 0 0 0 0 0 32.49

T3 10 96 3 0 0 0 0 0 0 0 33.31

3.5.4. Tnh cc hshi quy

Bng 3.11. Gi trcc hsb trong phng trnh hi quy y

b0 27.03 b12 - 1.49

b1 - 1.02 b13 - 0.10

b2 1.64 b23 0.28

b3 2.02 b123 0.19

3.5.5. Kim nh tnh ngha ca cc hshi quy v stng

thch ca phng trnh

Bng 3.12. Gi trcc chun Student thc nghim ttn

t0 124.713 t12 6.859

t1 4.728 t13 0.461

t2 7.550 t23 1.315

t3 9.302 t123 0.895

Tra bng phn bphn vchun Student (tb) vi mc ngha

p = 0,05 bc to f = 2 ta c: t0,05;2 = 4,3.

Do t13 , t23 , t123 < tp(f) nn h s b13, b23, b123 khng c

ngha, ta loi ra khi phng trnh, lc ny phng trnh hi quy c

dng:

y = 27.03 - 1.02x1 + 1.64x2 + 2.02x3 - 1.49x1x2 (3.9)

Bng 3.13. Cc gi trtnh lch d


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STN yu uy 2

uyuy

1 22.90 24.68 3.17

2 24.42 25.68 1.59

3 28.97 27.39 2.50

4 23.76 25.34 2.50

5 26.95 28.15 1.42

6 27.29 26.10 1.427 33.38 31.99 1.94

8 28.55 29.94 1.94

Suy ra Fb = F(0,05; 3; 2) = 19.13, do Ftn< Fb(f1f2), phng trnh thu

c tng thch vi thc nghim v phng trnh ny c sdng

tm kim ti u. PTHQ (3.9) hon ton tuyn tnh nn ta c thtm iu

kin ti u bng phng php leo dc (phng php Box-Wilson).

3.5.6. Ti u ho thc nghim

Bng 3.14. Cc iu kin cn thit tin hnh th nghim leo dc

Cc chtiu Z1,% Z2, h Z3, g/l

Mc cs 10 96 3

Khong bin thin (j) 2 12 1

Hsbj - 1.02 1.64 2.02

bjj - 2.04 19.68 2.02

jjb 2.04 19.68 2.02

Bc chuyn ng (j ) - 0.373 3.6 0.369

Lm trn bc chuyn ng ( j ) - 0.4 3.6 0.4

Bng 3.15. Kt quth nghim theo hng leo dc

22

Cc yu tnh hng Hm mc tiuTh nghim

Z1,% Z2, gi Z3, g/l Y

K hiu

mu

1(TN ti tm) 10 96 3 31.00 M122 9.6 99.6 3.4 33.91 M13

3 9.2 103.2 3.8 31.17 M14

4 8.8 106.8 4.2 28.88 M15

5 8.4 110.4 4.6 28.16 M16

Cn cvo kt ququi hoch thc nghim cho thy rng theo

hng leo dc th nghim th2 cho kt qutt nht vi hm lng axit

gluconic 33.91 g/100g mt rcao nht tng ng vi tlging bsung

9,6%, thi gian ln men l 99.6 gi, hm lng (NH4)2HPO43.4 g/l.

3.5.7. Th nghim kim chng

Kt quthu c hm lng axit gluconic 33.62 g/100g mt

r, kt quny gn tha mn gi trti u.

3.5.8. Kt lun

Bng phng php quy hoch thc nghim chng ti xy

dng c phng trnh ng hc m tmi tng quan ca cc yu

ttrong qu trnh ln men n hm lng axit gluconic.


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3.6. XUT QUY TRNH CNG NGH LN MEN AXIT

GLUCONIC TRNG BNG ASPERGILLUS NIGER

QUY M PTN

3.6.1. Quy trnh cng ngh

Pha long

Gia nhit

Ly tm

Rn

Chun bmi trng ln menKhong cht

Hot haA.niger Ln men

t = 30 oC

T= 96 gipH = 6.0

Hnh 3.15. Quy trnh ln men axit gluconic

Dung dch axit gluconic

H2SO40.2 M

Tch bB

Cn 96o

Dch

CaSO4

Lc tch dch

Lc tch kt ta

Tit trng

24

3.6.2. Thuyt minh quy trnh

Rng: c thu nhn tcc nh my sn xut ng.

Pha long: Pha long rng:nc (2:1 kg/kg) nhm thun

li cho qu trnh ly tm tch tp cht, gia nhit tiu dit tp khun.

Gia nhit: Gia nhit 85-90oC, ginhit trong khong

45-60 pht, hu ht cc tp khun btiu dit, sau l tm.

Ly tm: Nguyn liu c ly tm tch cc cht khng ha

tan trong mt r. Nguyn liu sau xl c bo qun 4oC

Tit trng: Mc ch ca qu trnh tit trng mi trng l

tiu dit cc vi sinh vt nh hng n qu trnh ln men. Tit trng

mi trng nhit 121oC v thi gian 30 pht.

Ln men: Thnh phn mi trng chun b vi hm lng

c cht mt r 150 g/l, (NH4)2HPO4 3 g/l, KH2PO4 0.5 g/l,

MgSO4.7H2O 0,1 g/l, CaCO340 g/l. iu chnh pH 6.0 bng H2S04

2.0 M, tin hnh ln men nhit 30oC, thi gian ln men 96 gi,

theo di pH mi trng ln men 6 gimt ln.

Ging:Ging sau khi hot ha m bo mt 106-107bo

t/ml vi t lging 10% (v/v). Mi trng ln men tit trng xong

ngui vnhit mi trng th tin hnh bsung ging.

Tch b: Sau 96 giln men tin hnh lc sch b, thu hi

dch canxi gluconat. Bsung cn kt ta canxi gluconat.

Tch dch: Sau khi kt ta canxi gluconat bng cn, lc thukt ta loi bdch, ra kt ta trn giy lc bng H2SO40.2 M.

Tch kt ta:Ra kt ta canxi gluconat trn giy lc bng

H2SO40.2 M, tin hnh loi kt ta CaSO4, thu c axit gluconic.


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KT LUN V KIN NGH

1. KT LUN

1) Rng nh my ng Kon Tum c cht lng ph

hp vi ln men axit gluconic c thnh phn ha hc nhsau:

Bx: 84.41

pH: 5.40

Protein: 3.64 (% cht kh)

ng kh: 22.70 (% khi lng)

ng tng: 54.50 (% khi lng)

ng saccarose: 30.21 (% khi lng)

2) xy dng phng php xc nh axit gluconic bng

my HPLC (Dionex - M) vi cc thng s nh sau: S dng pha

tnh l ct C18, tc dng 0,5 ml/pht, bc sng pht hin 210

nm, t l pha ng l acetonitrile:nc (3:7 v/v), t l axit H3PO4:

nc(1:1000 v/v), (pHnc= 2.5), mu phn tch c pH = 2.5.

3) Sau khi nghin cu nh hng ng thi 3 yu tn hiu

sut thu hi axit gluconic: tlging, gian ln men, hm lng nit

b sung bng phng php quy hoch thc nghim, TYT23 th

phng trnh hi quy thu c l:

y = 27.03 - 1.02x1+1.64x2+ 2.02x3 - 1.49x1x2

4) Khi ti u ha thc nghim bng phng php leo dc vi

cc thng sln men ti u: tlging 9.6%, thi gian ln men 99.6gi, lng (NH4)2HPO4 t3.4 g/l. Kt quthu c tth nghim i

chng hm lng axit gluconic t 33.62 g/100g mt r.

5) xut qui trnh ln men axit gluconic trng s

dngAspergillus nigerqui m PTN.

26

2. KIN NGH

1) Nn tip tc nghin cu cc yu tnh hng khc n

qu trnh ln men: nhit ln men, nng mt r, nng oxy,...

T xy dng phng trnh ti u ha cc qu trnh ln men

mnh dn xut quy trnh cng ngh ln men axit gluconic t r

ng bng chng nm mcA.nigerquy m pilot.

2) Nghin cu xl mu ca sn phm.

3) Nghin cu kt tinh sn phm to sn phm dng rn.

4) Nghin cu tn dng b thi ca mi trng sau ln men

lm thc n gia sc, phn bn vi sinh.

nghiên cứu quá trình lên men

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