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STUDY ON PRODUCING BACTERIAL STUDY ON PRODUCING BACTERIAL
Research institute for Aquaculture No2
116 Nguyen Dinh Chieu, Dist 1, HCM city116 Nguyen Dinh Chieu, Dist 1, HCM city
STUDY ON PRODUCING BACTERIAL STUDY ON PRODUCING BACTERIAL
DIGESTIVE ENZYME FOR USE IN DIGESTIVE ENZYME FOR USE IN
STRIPED CATFISH FEED TO IMPROVE STRIPED CATFISH FEED TO IMPROVE
FEED UTILIZATIONFEED UTILIZATION
Nguyen Van Nguyen Bach Quynh MaiNguyen Van Nguyen Bach Quynh MaiNguyen Van Nguyen, Bach Quynh MaiNguyen Van Nguyen, Bach Quynh Mai
Phạm Duy Hai, Giap Văn ThangPhạm Duy Hai, Giap Văn Thang
I. INTRODUCTION
OUTLINE
II. CONTENT
III. MATERIAL & METHOD
IV. RESULT & DISCUSSION
V. CONCLUSION
(5 sections)
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I. INTRODUCTIONI. INTRODUCTION
Currently, Striped catfish is one of the most
important aquaculture species.
 Feed cost is a large component in striped  Feed cost is a large component in striped
catfish production cost.
Improving feed utilization is concerning to
efficiency and sustainable aquaculture
• Consequently, our general objective that
improving feed utilization in striped
catfish by addition of bacterial
digestive enzymes

feed
in vitro
di ib
in vivo
l
Field
farming
Crude
enz
yme
Commercial
Protease
Mixtu
re A
Bi
commercial
Alpha amilase
commercial
Phytase
ivity
digestib
ivity
culture
farming
y
extract
Mixture of
bac.digest. E +
crude E. Extract
preparation

ation
Bacillus
subtilis
Bacillus
subtilis
Aspergillu
s niger
Trichoderm
a viride
mixtu
re D
III. III. MATERIAL AND METHODMATERIAL AND METHOD
1.Material:
Sampling
:
Tracatfishrangingfrom 50,
300 d 600 ll t d300 and 600gwerecollected.
Compounded pellet feed were used for
feeding only and routinely fed on 3 times
per day.
 Tra catfish previously starved for 12
hours before digestive tract removed
and dissected into stomach, intestine,
liver and pancreas
•
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2.METHOD2.METHOD
2.1.Determine the enzyme activities in the striped catfish digestive organs
2.1.1. PAGE Electrophoresis was used to characterize alpha amylase and

10.000 rounds/min , in 20
minutes
Supernatant filled in
eppendoff 1.5 ml
Stored at  -30
0
C
According to Alarcon et al.,1998; Hidolgo et al.,1999, Sampling
and process stage for collecting crude enzyme extract are two
main factors effect to enzyme activity.
Following Glass et al (1989), Das and Tripathi (1991); Dimes et
al (1994), the starved time of striped catfish relates with
enzyme activity
Some researches of Torrissen (1984); Das and Tripathi (1991);
Dimes et al (1994) và Chakrabarti et al (1995), they also mixed
organs with glass powder and centrifuge with different speeds
to collect Crude enzyme extract. Contrary to them, Hofer and
Schiemer (1981) và Uys and Hecht, (1987) conducted to
homogenize and filter for collecting the supernatant.
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2. 2. Electrophoresis to detect amylaseElectrophoresis to detect amylase
123
2.1. Characterization of amylase in pancreas and intestine
1 2 3
1 2 3
1 2 3
1 2 3
Tụy cá tra;1: cá kích cỡ 50 g;
2: cá kích cỡ 300 g; 3: cá kích cỡ 600 g;