Nguyễn Thế Hùng, Nguyễn Thị Lân - Nghiên cứu ảnh hưởng của một số loại cây trồng xen đến sinh trưởng và.. năng suất của giống dong riềng DR3 tại Trường Đại học Nông Lâm – ĐH Thái Nguyên [r]
Trang 1Tập 164, số 04, 2017
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CHUYÊN SAN KHOA HỌC NÔNG NGHIỆP - LÂM NGHIỆP - Y DƯỢC
Nguyễn Thế Hùng, Nguyễn Thị Lân - Nghiên cứu ảnh hưởng của một số loại cây trồng xen đến sinh trưởng và
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Lê Thị Kiều Oanh, Trần Văn Điền, Trần Đình Hà, Trần Trung Kiên - Đánh giá khả năng sinh trưởng và phát
Hà Đình Nghiêm, Nguyễn Thanh Hải, Đỗ Thị Lan, Nguyễn Thị Huệ - Quản lý cây trinh nữ móc (Mimosa
diplotricha) bằng mô hình dự đoán phân bố, mức độ xâm lấn và sử dụng sinh khối để trồng nấm 21
Nguyễn Thị Lân, Nguyễn Thế Hùng - So sánh, lựa chọn giống lúa năng suất cao, chất lượng tốt cho vụ mùa tại
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xây dựng bản đồ sinh khối và trữ lượng các bon rừng trồng thông thuần loài tại xã Nguyên Bình, huyện Tĩnh Gia,
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Đặng Minh Tơn, Đặng Văn Minh, Nguyễn Văn Toàn - Các loại đất chính, phân bố và tính chất trên địa bàn
Nông Thị Huyền Chanh, Hoàng Hữu Chiến - Nghiên cứu ảnh hưởng của hoạt động khai thác cát sỏi đến biến
Triệu Mùi Chản, Chu Văn Trung , Đỗ Sơn Tùng, Nguyễn Đình Thi, Nguyễn Thảo Yến, Bùi Thị Hường,
Hoàng Đông Quang - Xây dựng hệ thống lập quy hoạch kế hoạch sử dụng đất bán tự động 67
Nguyễn Văn Lợi - Nghiên cứu ảnh hưởng của nhiệt độ đến sự biến đổi chất lượng của quả vải thiều sau thu hoạch 75
Phạm Thị Phương, Nguyễn Thị Đoàn, Nguyễn Văn Bình, Nguyễn Thị Nhung, Lưu Hồng Sơn - Nghiên cứu hiệu
quả bảo quản của compozit của chitosan khối lương phân tử thấp với axit oleic ứng dụng trong bảo quản đào Pháp 81
Nguyễn Thị Kim Lan, Nguyễn Thị Ngân, Nguyễn Văn Quang, Phan Thị Hồng Phúc, Lê Minh, Phạm Diệu
Thùy, Trần Nhật Thắng, Dương Thị Hồng Duyên - Xác định serotype, độc lực và tính kháng kháng sinh của 3
Nguyễn Thị Thúy Mỵ, Trần Thanh Vân, Đỗ Thị Kiều Duyên - Ảnh hưởng của việc bổ sung chế phẩm Mfeed+
Từ Trung Kiên, Trần Thị Hoan, Nguyễn Văn Sơn- Ảnh hưởng của bổ sung dầu hạt lanh vào khẩu phần đến
Trương Hữu Dũng, Nguyễn Thị Hằng, Phùng Đức Hoàn - Đánh giá khả năng sinh trưởng và tiêu tốn thức ăn
của 3 tổ hợp lợn lai thương phẩm (DP x CA); (PD x CA) VÀ (LP x CA) giai đoạn sơ sinh đến 56 ngày tuổi 109
Sử Thanh Long, Nguyễn Công Toản, Trần Văn Vũ - Nghiên cứu một số yếu tố ảnh hưởng tới thời gian mang
Trần Thị Hoan, Từ Trung Kiên, Nguyễn Thị Hiền - Nghiên cứu ảnh hưởng của việc thay thế thức ăn viên
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Journal of Science and Technology
164 (04)
Trang 3Vũ Khánh Linh, Nguyễn Thị Hà, Nguyễn Thị Quỳnh Lâm, Lương Hùng Tiến - Phân lập và tuyển chọn một
số chủng vi sinh vật phân giải cellulose hướng tới tạo ra chế phẩm xử lý phế phụ phẩm nông nghiệp 133
Vũ Hoài Nam, Dương Văn Cường - Tăng cường sinh tổng hợp β-carotene trong Escherichia coli tái tổ hợp được
Nguyễn Thị Thu Ngà, Sỹ Danh Thường, Cao Thị Phương Thảo - Sử dụng mã vạch DNA để định loại loài Màn
Trịnh Đình Khá, Lý A Hù, Đặng Duy Phong, Nguyễn Hữu Quyền, Hoàng Thị Thiên Hương - Tổng hợp nano
Nguyễn Thị Thu Hà, Chu Thị Na, Cao Thị Phương Thảo - Nghiên cứu đặc điểm hình thái và giải phẫu một số
Phạm Thị Mỹ, Hoàng Thị Mai, Vi Đại Lâm, Dương Mạnh Cường - Thử nghiệm điều kiện ảnh hưởng đến sinh
trưởng của dòng vi khuẩn phân giải nitơ phân lập từ một số mẫu nước tại Trường Đại học Nông Lâm – ĐH Thái Nguyên 165
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Dương Hữu Lộc, Nguyễn Xuân Vũ, Vũ Thị Thu Thủy, Nguyễn Thị Tâm - Đặc điểm nông sinh học và mối
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Đinh Thị Huyền Chuyên, Sỹ Danh Thường, Trịnh Đình Khá, NguyễnThị Yến - Nghiên cứu đặc điểm hình
La Việt Hồng, Trần Hồng Thu, Phạm Thị Quy, Đinh Phương Thảo, Nguyễn Thị Thanh, Phạm Ngọc Khánh
- Xác định chỉ thị phân tử và tái sinh chồi in vitro của loài Hoàng tinh hoa đỏ (Polygonatum kingianum Coll ex
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Hạnh - Cao cây sương sáo (Mesona chinensis Benth.) có tác dụng hỗ trợ điều trị béo phì trên chuột nhắt trắng 195
Lê Phong Thu, Nguyễn Thu Thủy, Tạ Văn Tờ - Tổng quan đáp ứng mô bệnh học ung thư vú sau điều trị hóa
Hà Trọng Quỳnh - Lượng giá thiệt hại sức khỏe cộng đồng do ô nhiễm không khí tại phường Tân Long, thành
Nguyễn Thị Trung - Nghiên cứu khả năng nhận biết đặc hiệu các kháng nguyên của Listeria monocytogenes của
Trang 4Vũ Khánh Linh và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 164(04): 133 - 139
133
ISOLATION OF CELLULOLYTIC BACTERIA
TO TREAT AGRICULTURAL BY PRODUCTS
Vu Khanh Linh * , Nguyen Thi Ha, Nguyen Thi Quynh Lam, Luong Hung Tien
University of Agricultural and Forestry – TNU
SUMMARY
Isolation and selection consist of cellulolytic bacteria from natural resources such as rubbish, leaves, straw and wood decay has played an important role in the development of preparations responsible for agricultural waste treatment This study was performed in three kinds of different medium, such as MP, Czapek-Dox and ISP4; all of these ones were added with CMC substance Samples were collected in Phu Binh district, and 13 distinct bacteria with the diameter length of inhibition zone equal to 20 mm, were isolated Amongst 13 of these types of bacteria there consists
of 3 bacterial strains, 4 actinobacteria strains and 6 mildew strains In particular, the two types of microbes getting with the highest value of cellulolytic capacity were NM1 and NM3, which were derived from wood decay and decomposed straw, respectively; with the diameter of inhibition zone were equal to 46 mm and 40 mm subsequently Two types of microbes NM1 and NM3 were chosen in an attempt to conduct an experiment determining the optimum condition to generate and synthesis cellulose enzyme As a result, the cellulolytic capacity of these microbes was higher in Czapek Dox medium, which was added by 5 % amount of straw at pH = 5 and 400C and the period
of time for enzyme extraction was equal to 42 hours
Keywords: Actinobacteria, Cellulolytic bacteria, CMC, Czapek-Dox medium, Mildew
Agricultural waste is considered as an
auxiliary product generated by the planting,
breeding and farming process, which
produced before and after harvest period
Agricultural waste treatment has a great
influence on agro – environmental quality,
development [3] To conduct agricultural
waste treatment, many recent national and
global researches have indicated that using
bio – method is optimum and efficient in
order to maintain environmental quality
Cellulose is the most abundant biological
polymer on the earth [4] Each year, there is a
large volume of organic substance derived
from the photosynthesis process This induces
a high degree of cellulose in agricultural land,
which comes from bio-synthetic products
such as dead trees, falling branches and
leaves, rubbish, scrap paper and sawdust
released by human activities Vietnam is one
*Tel: 01642532867; Email: Vukhanhlinh115@gmail.com
of agricultural producing countries, which has contributed to generate organic waste source containing a huge amount of cellulose, which
is the main composition of agricultural waste
In fact, the application of cellulolytic microorganisms in agricultural waste treatment for many kinds of products, including straw, bagasse, wood decay, etc has been developed
in many countries around the world for environmental treatment, animal food production by using agro – waste [1], [5] In this study, our ambition is to isolate and characterize cellulolytic bacteria strains that play a vital role in developing biological products for waste treatment and enhancing economic efficiency in agricultural production MATERIALS AND METHODS
Research object
Object in this study is isolating and selecting consist of cellulolytic bacteria from natural resources such as rubbish, leaves, straw and wood decay, decomposed straw were taken in Phu Binh district, Thai Nguyen province
Trang 5Vũ Khánh Linh và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 164(04): 133 - 139
134
Methodology
Bacterial isolation, implantation and retention
were performed in Crapek – Dox medium
The implantation of bacteria was carried out
by using a kind of medium which was similar
to Crapek – dox medium without agar
Applying medium containing compositions
which was resemble like of Crapek – dox
medium and replacing carbon sources by
CMC (cacbonxylmethyl cellulose) was
responsible for evaluating cellulase active
capacity of bacteria strains
Method for treatment of samples
Decomposed leaves, rubbishes, straw and
wood decay were collected in Phu Binh
district, Thai Nguyen province with around 20
grams of each sample was taken per once
After, the sample will be for plastic bags,
which was marked and filled information
about time and place of taken sample Then,
these samples were preserved in dry, avoid the
sun in cool places before isolation process
The isolation method
Isolated conducting
Taken 1 gram of each sample and diluted with
different levels (from 10-1 to 10-6) Next, plating
onto agar medium to feed Crapek- Dox in an
incubator, counting the number of colonies
grown from medium after 48 hours and
processing the results Then, the inoculated seed
is obtained and conserved on agar
Method of active testing
Method of determining the enzyme activity by
scoring method
Cellulose is qualified by using “dot method”
The inoculator loop was chosen for taking a
little amount of bacteria colonies into agar slant
Then one dot was transplanted into agar plate
which contained 1% CMC, after that cultured
about 3-4 days in the Incubator chamber
Showed clear zone by a red lugon reagent 1%,
the enzyme active was determined by
arithmetical difference (D-d, cm)
With D: the clear zone diameter
d : the bacteria diameter
Method of determining the enzyme active by diffusion method on agar
A cork border was applied to create a bunch
of holes in agar culture surface testing enzyme activity and these holes were matched
to each type of enzyme Then, these holes were dripped 100 μm of prepared enzyme solution and hence all these samples were put into a refrigerator in 6 – 8 hours in order to perform agar diffusion before positioning in incubator chamber in 24 hours at 30°C The presence of clear zone was conducted by using Lugol’s solution 1% The enzyme activity value was determined by calculating the difference between D and d (D – d, cm) With: D is the diameter of inhibition zone
d is the diameter of punched hole
Method of the laboratory layout for determining the suitable culture condition
Method for determination of optimum period
of time for bacteria growth
The implantation of microbes was conducted
by shaker with the optimum speed at 200 rounds per minute in various periods of time including 6; 12; 18; 30; 36; 42; 48; 54 and 60 hours, respectively After that, biomass derived from the step above and activated
capacity of enzyme was recorded
Method for determination of optimum temperature for bacteria growth
A Mildew were cultured in a semi-solid environment at temperatures: 25; 30; 35; 40; 45; 50oC After 36h – 48h at 50°C, these samples were milled smoothly by ball mill and poured 4 – 5 times higher amount of water in comparison with culture weight in order to solute protein – enzyme from mycetocyte culture Afterwards, cellulase
enzyme activity was measured its value Method of determining the suitable level sensor
The mildew was cultured liquid and shook 200 rev/min in the environment, which was containing inducers concentration from 1% - 8% After 36 - 48 hours, it was collected, filtrated and
determined enzyme cellulase active
Trang 6Vũ Khánh Linh và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 164(04): 133 - 139
135
Method of determining the suitable pH
environment
The mildew was cultured liquid and shook
200 rev/min in the environment with pH is
3,4,5,6,7,8 at room temperature After 36 - 48
hours, it was determined enzyme active
Method of data processing
The data was calculated by the software Excel
and Processing performed on the computer by
IRRISTAT 4.0 program
RESULT AND DISCUSSION
Isolation of bacteria has high cellulase
enzymes
A selection of bacteria was capable of
generating cellulase enzyme and hydrolyzed
cellulose, we conducted to isolated samples
from Phu Binh district, Thai Nguyen province
Used agar to isolate bacteria, Capek and ISP4
environment was carried out in order to isolate
mildew and antinobacteria (respectively)
The isolated result showed 13 these types of
bacteria that consists of 3 bacteria strains(VK),
4 actinobacteria strains(XK) and 6 mildew strains (NM) In particular, the mildew strain accounted largest about 46.1%, the bacteria strains and antinobacteria strains to appropriated aproximately 53.9% The most strain was isolated on wood decays
Result of active testing
In order to test whether isolated bacteria was capable of generating cellulase enzyme, we used "dot method" on Crapek-dox has 1% CMC After 3 days, we measured the diameter
of cellulase resolution The result of active testing showed in table 2
As indicated by the results, the ability of these types of bacteria is different biosynthesis The different types of bacteria were isolated and bacteria was capable of generating cellulase enzyme in 13 types of bacteria Two types of bacteria getting the highest cellulase enzyme activiy includes (1) NM1 which was extracted from wood decay sample and (2) NM3 was generated from straw decay
Table 1 Results and Particular of bacteria were saparated
Sample No
Bacteria colonies
The characteristic of
bacteria colonies The particular traits of
cellular The color of
bacteria colony
Time appear
Leaves
decaying
1 VK1 Milky-white 3 days Globular, viscous surface
2 VK2 Milky-white 2 days Globular, viscous surface
3 XK1 Yellow 3 days Figure yarn, terry surface,
multiple fiber links
4 XK2 White 3 days Figure yarn, smooth surface
Wood
decaying
5 VK3 White 1 day Globular, viscous surface
6 NM1 Black 3 days
Figure yarn, mycelia with walls, Ceiling spores has sphere
7 XK3 Yellow 2 days Spherical, fibrous interlinked
8 XK4 Yellow 2 days Sphere, having branched
fibers
9 NM2 Dark brown 4 days Figure yarn, having many
colors on bacteria colony
Straw
decaying
10 NM3 Black 2 days Figure yarn, many fibers
11 NM4 Black 3 days Figure yarn
12 NM5 Yellow 3 days Figure yarn, the mycelium
without walls
13 NM6 Brown 3 days Figure yarn, the mycelium,
branching
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136
Table 2 Result active testing
Sample No.1 Bacteria
colonies
Cellulase active (D-mm)
Leaves
decaying
1 VK1 27
2 VK2 24
3 XK1 23
4 XK2 30
Wood
decaying
5 VK3 36
6 NM1 46
7 XK3 31
8 XK4 36
9 NM2 28
Straw
decaying
10 NM3 40
11 NM4 36
12 NM5 32
13 NM6 24
Figure 1 Pictures of active testing bacteria
cultured
Determination of some factors were
affected by the ability of bacteria was
capable of generating cellulase enzyme in
NM1, NM3 were selected
The influence of time
Results of analysis showed that bacteria was
capable of generating extracellular cellulase
enzyme of NM1, which strongly increased at
6 cultured hours from 17% (6mm) to 94%
(33mm) at 30 cultured hours , it reached
maximum 100% (35mm) at 36 hours, then it
decreased from 91.5% (32mm) at 48 hours
and dramatically dropped 83% (29mm),
51.5% (18mm) after 60 hours Therefore,
NM1 was largest capable of generating
extracellular cellulase enzyme after 30 ÷ 48
cultured hours and the maximum at 36 hours
Similarly, NM3 was strongly capable of
generating extracellular cellulase enzyme at
30-54 hours and which was reached a
maximum of 100% (31mm) at 42 cultured hours, after it was going down to 71% (22mm) at 60 cultured hours The results of our study showed that two strains mildew NM1 and NM3 have time strongest cellulase biosynthesis in 36-48 cultured hours This result is consistent with Nguyen Duc Luong (2003) [2]; Nguyen Trong Can et al (1998) suggested that fiber fungus grows from 36-48 hours with high cellulase enzyme activity; while actinobacteria strain takes at least 72
hours for synthesize cellulase [5]
Table 3 The affected results of culturing period to
the ability biosynthesis cellulase in bacteria NM1,
NM3
Bacteria colonies
Time (h)
Cellulase active (D-mm)
The biomass (g/l)
NM1
0 0h 2,216k
6 6g 3,325j
12 16f 4,913i
18 20e 7,441h
24 26d 8,847e
30 33b 9,778b
36 35a 9,897a
42 33b 9,747c
48 32b 9,235d
54 29c 8,135f
60 18d 7,736g
CV( %) LSD 0,05
6.20 1.23
7.10 0.47
NM3
0 0g 2142k
6 4f 3,116j
12 11e 5,344i
18 16d 7,962h
24 25c 8,875d
30 29a 9,372c
36 30a 9,675b
42 31a 9,873a
48 29a 8,530e
54 28a 8,213f
60 24c 8,157g
CV%
LSD 0.05
6.10 2.14
4.90 0.91
The influence of temperature
As a result, when the temperature rose from
25 oC to 35 oC, the NM1 activity increased rapidly and reached maximum value at 35 oC
In particular, the cellulase activity was 27 mm
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137
at 25oC, which was 37 mm at 35oC If the
temperature increased, the cellulase activity
was decreasing and lost activity at 50oC NM3
gradually increased cellulase activity at 40oC
(36 mm) when the temperature increased
from 25oC to 40oC, then which was going
down to lose activity at 50oC The NM3
strains cellulase activity gradually increased
at 40oC (36mm) when the temperature
increases from 25 – 40oC, then descending to
inactivation at 50oC As the temperature goes
up slowly, the enzymatic activity will
gradually increase to the optimum level Each
enzyme has a temperature that it works
optimally If the temperature is higher than
the optimal temperature, the enzyme activity
will be reduced So, the two ends of the
activity range for an enzyme is determined by
what temperature starts the activity and what
temperature starts to break down the protein
Due to the nature of the enzyme is protein,
when high temperature will denature protein
leading to inactivation enzyme
Table 4 The affected of Temperature to the ability
to produce enzyme cellulase from bacteria NM1,
NM3
Bacteria
colonies
Temperature
( o C)
Cellulase active (D-mm)
NM1
25 27d
30 33b
35 37a
40 31c
45 25e
50 0f
CV (%)
LSD 0,05
4.10 1.32
NM3
25 30c
30 32b
35 33b
40 36a
45 27d
50 0e
CV (%)
LSD 0,05
3.30 1.59
The influence of initial pH
pH environment strongly influenced on the growth and the profound impact on the metabolism of microorganisms The slightest change in the concentrations of ions which also strongly influenced to microorganisms From the Figure shows the ability of extracellular cellulase biosynthesis of potent strains NM1 and NM3 about pH 3-5, strains NM3 about pH 3-6 and also reach a maximum at pH 5 (36 mm with strains NM1,
34 in NM3 strain) In this pH range cell biomass is highest and the maximum at pH 5 (9.743 g/l with strains NM1 and 8.565 g/l with strains NM3) At pH <3 and pH> 6 extracellular cellulase activity of this strains only reached 53% - 83% activity compared with the maximum activity, biomass also reached 72-87% compared to the maximum After culturing all of the culture medium are
pH decreased slightly from the initial pH Enzyme is very sensitive to the pH of the medium; pH plays an important role in the reaction rate of enzyme A change in pH changes the protonation pattern and can, in some cases, result in protein denaturation In general enzyme have a pH optimum However the optimum is not the same for each enzyme Any change in pH above or below the optimum will quickly cause a decrease in the rate of reaction Compared to previous studies, the fungus strains produced the strongest cellulase synthesis in pH 4.5-5.5 (Nguyen Duc Luong, 2003, [2]); pH 5 - 6 (Trinh Dinh Kha, 2006, [6]); the initial pH is
6 to 10 with the bacterial isolates, and the antibiotic is 7-10 with the bacterium (Le Kim Bang et al., 1999, [1]) Therefore, the strains filamentous fungi cellulase biosynthesis strongest in the pH about from 4.5 to 6 (acidic conditions) and consistent with the previous results
Trang 9Vũ Khánh Linh và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 164(04): 133 - 139
138
Table 5 The result affected of the initial pH affects to the biosynthesis cellulase of bacteria NM1, NM3
Bacteria colonies Initial pH The biomass after
feeding (g/l)
Cellulase active (D-mm)
pH after culturing period
NM1
2 8,055c 20e 1,967e
3 9,684b 31b 2,472d
4 9.672b 31b 3,834c
5 9,743a 36a 4,241a
6 9,678b 28c 4,181a
7 7,130d 27c 4,055b
8 7,015e 25d 4,356a
CV (%)
LSD 0,05
3.40 0.34
3.20 1.047
3.90 0.159
NM3
2 7,364f 18e 1,854e
3 8,349c 32b 2,549d
4 8,251d 31b 3,783c
5 8,565a 34a 4,770a
6 8,437b 31b 4,820a
7 7,437e 28c 4,127b
8 7,041f 26d 4,116b
CV (%)
LSD 0,05
2.50 0.23
5.80 1.90
3.20 1.39
The influence of Substrate concentration to
substrates resolution of bacteria NM1 and NM3
Table 6 The result effected of the inducer
concentration to the ability of resolution substrate
of bacteria NM1, NM3
Bacteria
colonies
Concentration
(%)
Straw Wood
NM1
1 25f 20f
2 27e 22e
3 40c 23d
4 42b 25c
5 57a
28d
6 28d 29a
7 26e 30a
8 25f 24c
CV (%)
LSD
4.60 1.24
4.20 1.51
NM3
1 24e 19g
2 26d 20f
3 34b 22e
4 35b 22e
5 43a 29b
6 30c 30a
7 26d 28c
8 24e 26d
CV(%)
LSD
4.80 1.27
2.10 0.68
Results showed when the substrate were increasing, the probability of resolution grew
up in both NM1 and NM3 with the rate from 1% to 5% The cellulase ezyme activity of two bacterias reached maximum with concentration about 5% (57 mm with NM1 and 43 mm with NM3) Then, If the substrate rose more than 5%, the activity of both enzymes were significantly reduced With a certain amount of enzyme, if which was increasing the amount of substrate in the solution The first time, the activity of the enzyme sharply increases then Increasing the substrate concentration does not increase the activity of the enzyme Increasing Substrate Concentration increases the rate of reaction This is because more substrate molecules will
be colliding with enzyme molecules, so more product will be formed However, after a certain concentration, any increase will have
no effect on the rate of reaction, since Substrate Concentration will no longer be the limiting factor Because all active centers have been saturated by substrates The
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enzymes will effectively become saturated,
and will be working at their maximum
possible rate
CONCLUSION
Through the research results obtained by
experiments conducting in the laboratory of
the Technology Faculty of microbial
biotechnology - Agriculture and Forestry
University, results have isolated 13 strains of
microorganisms cellulase activity from
samples collected in Phu Binh District - Thai
Nguyen Since many strains have been
isolated, we have identified the activity of 13
strains and we identified two strains that have
the highest cellulase activity NM1 and NM3,
the 2 strains are the result resolution cellulose
substrate best culture conditions are as
follows: pH: 5, cultured temperature 40oC, 42
cultured hours, the inducer concentration
optimal 5% with straw From the results of
the evaluation cellulase activity,
corresponding (D-d) is 57 mm of NM1 strains
and the NM3 strains is 43 mm
REFERENCES
1 Ly Kim Bang, Le Gia Hy, Tang Thi Chinh, Phan Tuyet Minh, Le Thanh Xuan, Tran Quang Huy, Dao Ngoc Quang, Pham Thi Cuc (1999),
“Use of microorganism have high activity cellulase resolution to improve quality decomposition domestic waste and agriculture”
Report Sciences, Biotechnology national Conference, Science and Technics, Ha Noi
Publishing House
2 Nguyen Duc Luong (2003), “Coffee producing
by enzyme method”, Scientific reports biotechnology conferences nationwide, Science and Technics, Ha Noi Publishing House
3 Nguyen Van Mui, Biological safety, Vietnam
Education Publishing House, 2009
4 Schwarz, W H (2001), “The cellulosome and cellulose degradation by anaerobic bacteria”,
Appl Microbiol Biotechnol, 56, pp 634 - 649
5 To Kim Anh (2010), Created recombinant enzyme
preparations lignocellulose hydrolysates for fuel alcohol production, Science and Technology the
theme State level KC - 04 2009-2010
6 Tran Dinh Kha (2006), Selection, culturing the
microorganism species biosynthetic enzyme cellulase and evaluate physical and chemical properties of cellulose, Science master's thesis,
University of Natural Sciences, Ha Noi National University
TÓM TẮT
PHÂN LẬP VÀ TUYỂN CHỌN MỘT SỐ CHỦNG VI SINH VẬT
PHÂN GIẢI CELLULOSE HƯỚNG TỚI TẠO RA CHẾ PHẨM
XỬ LÝ PHẾ PHỤ PHẨM NÔNG NGHIỆP
Vũ Khánh Linh * , Nguyễn Thị Hà, Nguyễn Thị Quỳnh Lâm, Lương Hùng Tiến
Trường Đại học Nông Lâm - ĐH Thái Nguyên
Phân lập và tuyển chọn bộ chủng vi sinh vật phân giải cellulose từ các nguồn tự nhiên như rác thải,
lá cây, gỗ cây mục, rơm rạ mục đóng vai trò quan trọng trong việc phát triển chế phẩm xử lý rác thải nông nghiệp Nghiên cứu tiên hành phân lập các nhóm vi sinh vật trên môi trường MP, Czapek Dox và ISP4 có bổ sung CMC Từ các nguồn vật liệu thu được tại huyện Phú Bình, nhóm nghiên cứu đã phân lập được 13 chủng vi sinh vật có đường kích vòng phân giải cellulose ≥ 20
mm, bao gồm 3 chủng vi khuẩn, 4 chủng xạ khuẩn và 6 chủng nấm mốc Kết quả phân giải cellulose tốt nhất thu được từ hai chủng nấm mốc NM1 phân lập từ gỗ mục và nấm mốc NM3 phân giải từ rơm rạ đang phân hủy, với đường kính vòng phân giải cellulose tương ứng là 46 mm với chủng NM1 và 40 mm với chủng NM3 Nhóm nghiên cứu lựa chọn hai chủng nấm mốc NM1
và NM3 để tiếp tục tiến hành các nghiên cứu xác định các điều kiện nuôi cấy phù hợp cho khả năng sinh trưởng, phát triển và sinh tổng hợp enzyme cellulose Hai chủng nấm mốc NM1 và NM3 sinh trưởng, phát triển và cho khả năng phân giải cellulose tốt với điều kiện nuôi cấy là môi trường Czapek Dox có bổ sung 5% rơm, pH = 5, nhiệt độ nuôi cấy 40oC, thời gian thu enzyme là 42 giờ
Từ khóa: Xạ khuẩn, phân giải cellulose, CMC, môi trường Crapek-Dox, nấm mốc
Ngày nhận bài: 19/01/2017; Ngày phản biện: 14/3/2017; Ngày duyệt đăng: 27/4/2017
*Tel: 01642532867; Email: Vukhanhlinh115@gmail.com
