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Effect of nutrient components for phytase production by Aspergillus niger
Section 2. Biotechnology
Kaliyeva Aigul, Department of Biochemistry, LLP Antigen, Ph.D, Senior researcher Almaty, Kazakhstan Zhanara Suleimenova, Department of Biochemistry, LLP Antigen, Ph.D, Senior researcher Almaty, Kazakhstan E-mail: msyban@mail.ru Nurlan Akhmetsadykov, Department of Biochemistry, LLP Antigen, Professor, Head Almaty, Kazakhstan Zhazira Saduyeva Department of Biochemistry, LLP Antigen, MS, Junior researcher Almaty, Kazakhstan
Effect of nutrient components for phytase production by Aspergillus niger
Abstract: In present study the effect of carbon sources, glucose, sucrose, lactose, maltose, fructose, xylose and nitrogen sources such as ammonium sulfate, ammonium phosphate, ammonium nitrate, potassium nitrate, yeast extract, peptone on the phytase production has been studied. Maximal phytase activity of Aspergillus niger was detected in media with 1.0% sucrose as a carbon source. All other monosaccharides and disaccharides used had less effect on phytase production. Among the inorganic and organic nitrogen sources, ammonium nitrate in concentration of 0.5% was found to be a favorable nitrogen source for phytase production in Aspergillus niger Keywords: phytase, carbon source, nitrogen source, poultry, Aspergillus niger.
One of the major components of poultry fodder is wheat, soybean meal, corn, which serve as an indispensable source of protein, carbohydrates, calcium and phosphorus. However, those substances are contained in fodder in the form of complex indigestible conglomerates bound by complex organic compounds — phytates and cannot be digested by birds. One of the solutions of this critical issue is the introduction into the poultry diet of phytase. Phytase is a specific enzyme that initiates the decomposition of phytate — phytic compounds, which contain 70-90% of the total phosphorus in plant. Due to the inability of poultry to produce own phytase availability of phosphorus, calcium, protein and other nutrients is limited. The use of phytase provides a new qualitative approach to improving fodder efficiency and reducing nutrients consumption per unit of livestock production. In spite of the fact that phytases from several species of bacteria, yeast and fungi have been characterized, commercial production of this enzyme currently focuses on fungi of the Aspergillus because of high productivity [1,
585; 2, 581]. However, great drawback of industrial fungal strains is their low activity, despite the fact that the essential requirement to enzymes is their high activity.
The production of phytase have been affected by a variety of physical and chemical factors, such as the composition of the growth medium, cell growth, methods of cultivation, inoculum concentration, time of incubation, pH, temperature, carbon, nitrogen and mineral sources etc. [3, 211-217; 4, 3-14]. However, composition of the cultivation medium (carbon and nitrogen sources) play significant role on enzymes production. The effect of different carbon and nitrogen sources on phytase production by Aspergillus niger was investigated.
Materials and Methods:
Media: Aspergillus niger was maintained on Czapek Dox agar (g/l): glucose — 30, NaNO3-3, K2HPO4-1, MgSO4-0.5, KCl — 0.5, FeSO4-0.001, pH 5.5.
Phytase production in submerged fermentation: Submerged fermentation was carried out to study the effect of carbon and nitrogen sources on phytase production
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Section 2. Biotechnology
by Aspergillus niger using the following cultivation medium: 0.5% (NH4)2SO4, 0.05% KCl, 0.01% MgSO47H2O,
0.01% NaCl, 0.01% CaCl2, 0.001% FeSO4, 0.001% MnSO4, 1,5% sucrose, pH 6.5.
For inoculum preparation, 25 ml of sterile distilled water was added to the 5-day-old culture grown on Czapek agar plate and scraped aseptically with inoculating loop. This suspension, having spore concentration of 1.3-10 7 cells/ml, was used as inoculum for the cultivation. Aspergillus niger isolate was cultivated for 72h at 30°C on production medium enriched in the various carbon and nitrogen sources.
Phytase assay: phytase was determined by spectro-photometric method (State Standard of Russian Federation 53360-2009).
Effect of Carbon and Nitrogen Sources: Different pure carbon sources (e. g. glucose, sucrose, lactose, maltose, fructose and xylose) with concentration of 1,5% were added to basal medium replacing sucrose (control) to
analyze their effect on phytase production. Enzyme production was optimized by using different organic and inorganic nitrogen sources such as ammonium sulfate, ammonium phosphate, ammonium nitrate, potassium nitrate, peptone and yeast extract with concentration of 0.5% incorporated in basal medium replacing ammonium sulfate (control).
Results and discussion:
Effect of different carbon sources on phytase production by Aspergillus niger.
The results indicated that among the various (fructose, maltose, glucose, xylose, lactose and sucrose) carbon sources used for phytase production, sucrose is a suitable carbon source for maximal phytase activity of 1150 U/g (Fig. 1). All other monosaccharides and disaccharides used had less effect on phytase production (enzymatic activity ranged from 670 U/g to 900 U/g). This indicates that sucrose is the most efficient source for phytase production by A. niger.
Fig. 1. Effect of different carbon sources on phytase production by Aspergillus niger in submerged fermentation The effect of different concentration of sucrose on of 0.25 to 2% (Fig.2). Sucrose at 1.0% concentration was
phytase production was studied using sucrose in the range found to support maximal phytase activity (1250 U/g).
Fig. 2. Effect of different concentrations of sucrose on phytase production by A. niger in submerged fermentation
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Effect of nutrient components for phytase production by Aspergillus niger
Effect of different nitrogen sources on phytase production by Aspergillus niger
The result obtained through the studies on the effect niger phytase production in submerged fermentation is of inorganic and organic nitrogen sources on Aspergillus shown in Figure 3.
Fig. 3. Effect of nitrogen sources on phytase production by A. niger in submerged fermentation
Among the various nitrogen sources such as ammonium sulfate, ammonium phosphate, ammonium nitrate, potassium nitrate, yeast extract, peptone used for phytase production, ammonium nitrate supported phytase production in A. niger with enzymatic activity of 1320 U/g. All other nitrogen sources used had less
effect on phytase production with enzymatic activity from 850 U/ml to 1200 U/g. The various concentration of ammonium nitrate (0.25% — 2.0%) have been used for the phytase production in submerged fermentation (Fig. 4). It was found that 0.5% ammonium nitrate has given the highest enzymatic activity (1320 U/g).
Fig. 4. Effect of different concentrations of ammonium nitrate on phytase production by A. niger in submerged fermentation
Thus, among the different nitrogen and carbon sources tested 0.5% ammonium nitrate and 1.0% sucrose were found to be good nitrogen and carbon sources for phytase production.
Acknowledgements: This research work was funded by Ministry of Education and Sciences of the Republic of Kazakhstan
References:
1. Sayim Akturk, Hatice K. Güvenmez, Sadik Din$er Purification and characterization of extracellular phytase from Aspergillus niger//Current Opinion in Biotechnology Vol. 24, 2013. P. 585.
2. Gamze Sevri Ekren, Kubilay Metin Production, purification and characterization of phytase from phytase producing fungus//Current Opinion in Biotechnology Vol. 24, 2013. P. 581.
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Section 2. Biotechnology
3. Purva Vats, U.C Banerjee Studies on the production of phytase by a newly isolated strain of Aspergillus niger var teigham obtained from rotten wood-logs//Process Biochemistry Vol. 38, Issue 2, 2002. P. 211-217.
4. Purva Vatsa, Uttam C Banerjee Production studies and catalytic properties of phytases (myo-inositolhexakispho-sphate phosphohydrolases): an overview//Enzyme and Microbial Technology Vol. 35, Issue 1, 2004. P. 3-14.
Hafizov Qarib Kerim oglu, head of the laboratory of biochemistry and processing of fruit of Azerbaijan Science Research Institute of Horticultural and Subtropical Crops
E-mail: hafizov-54@mail.ru Hafizov Samir Qarib oglu, specialty in processes and equipment for food production in the laboratory of biochemistry and processing of fruit of Azerbaijan Science Research Institute of Horticultural and Subtropical Crops
E-mail: hafizovsamir@bk.ru
Biochemical peculiarities of persimmons fruits storage convention and refrigerated conditions
Abstract: We studied the change in weight, and shelflife ofpersimmons in conventional and refrigerated conditions depending on the degree of pollination and some chemical parameters of the particular fruit pomology varieties. It was found that by using the characteristic organoleptic properties of freshly fruits and chemical indicators can predict with certainty the timing of their storage and take into account the decline in the weight of the fruit, as well as to anticipate future changes in the content of nutrients and bioactive substances.
Keywords: persimmon fruit, varietal characteristics, duration of storage, the nutritional value, decline in the mass, Azerbaijan.
Гафизов ГарибКерим оглы, заведующий лабораторией биохимии и переработки плодов Азербайджанского Научно-Исследовательского Института Садоводства и Субтропических Культур E-mail: hafizov-54@mail.ru Гафизов Самир Гариб оглы, специалист по процессам и аппаратам пищевых производств лаборатории биохимии и переработки плодов Азербайджанского Научно-Исследовательского Института Садоводства и Субтропических Культур E-mail: hafizovsamir@bk.ru
Биохимические особенности хранения плодов хурмы в обычных и охлаждаемых условиях
Аннотация: В работе изучены происходящие изменения в массе и сроках хранения хурмы в обычных и охлаждаемых условиях, в зависимости от степени опыления и некоторых химических показателей плодов конкретного помологического сорта. Установлено, что используя характерные для свежесобранных плодов органолептические свойства и химические показатели, можно с большой уверенностью прогнозировать сроки их хранения и учитывать убыль в массе плодов, а также предугадывать грядущие изменения в содержании питательных и биологически активных веществ.
Ключевые слова: плоды хурмы, сортовые особенности, длительность хранения, убыль в массе, пищевая ценность, Азербайджан.
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