Shruthi SD et al. IRJP 2012, 3 (8) OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE...

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Shruthi SD et al. IRJP 2012, 3 (8) Page 135 INTERNATIONAL RESEARCH JOURNAL OF PHARMACY www.irjponline.com ISSN 2230 – 8407 Research Article PRODUCTION OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS Mamatha J, Suresh V, Vedamurthy AB, Shilpi B and Shruthi SD* P.G. Department of Biotechnology, The Oxford College of Science, Bangalore 560102, Karnataka, India Article Received on: 18/06/12 Revised on: 22/07/12 Approved for publication: 19/08/12 *Email: [email protected] ABSTRACT α-amylases are ubiquitous enzymes produced by plants, animals and microbes, where they play a dominant role in carbohydrate metabolism. In spite of the wide distribution of amylases, microbial sources, namely fungal and bacterial amylases, are used for the industrial production due to advantages such as cost effectiveness, consistency, less time and space required for production and ease of process modification and optimization. Filamentous fungi are known to be prolific producers of extracellular proteins; they are widely exploited for the production of different enzymes including a-amylase. SSF is generally defined as the growth of microorganisms on moist solid substrates with negligible free water, which is preferred than SmF because of simple technique, low capital investment, lower levels of catabolite repression, end- product inhibition, low waste water output, better product recovery and high quality production. Different substrates such as wheat bran, mollasses bran, rice bran, maize meal and sugarcane bagasse were used; out of which sugarcane bagasse has been reported to produce promising results. Different carbon and nitrogen supplements were given which increased the yield of the enzyme and optimized the pH as 6.0 and temperature 30 0 C. Thus the maximum production of amylase was observed at optimized conditions, which can be employed in large scale. Keywords: α-amylase, A. flavus, sugarcane bagasse, pH, supplement, temperature INTRODUCTION Microbial starch utilization is responsible for one of the largest material flows in the biosphere and is of interesting relation to analysis of carbon flux at both local and global scales. The importance of microbial starch and cellulose utilization in natural environments is further enhanced by the status of ruminants as a major source of dietary carbon. Microbial cellulose and starch utilization is also an integral component of widely used processes such as anaerobic digestion and composting 1 . A promising strategy for efficient utilization of the resources is the microbial hydrolysis and fermentation of waste materials rich in starchy substances and of the resultant reducing sugar for production of desired metabolites or biofuel 1 . Effective bioconversion processes of starchy materials depend mainly on the good sources of enzymes, the nature of starchy substances and the optimal conditions for production and catalytic activity of the enzymes 2 . Fungal α-amylase is preferred for use in formulations for human or animal consumption involving applications under acidic conditions and around 37°C. Similarly, due to its biocompatibility, fungal amylases are preferred in baking and food processing. With the advent of new frontiers in biotechnology, the spectrum of amylase application has expanded into many other fields, such as clinical, medical and analytical chemistry. To develop an efficient enzyme based process, prior knowledge of optimum growth conditions, various fermentation parameters, purification strategies and properties of the biocatalyst is of most importance. α-amylases (EC 3.2.1.1, endo-1,4-α-D-glucan glucohydrolase) are endo-acting enzymes which randomly hydrolyze α-1,4-glycosidic bonds between adjacent glucose units in a starch polymer leading to the formation of linear and branched oligosaccharides. They are usually used in synergy with glucoamylases or β-amylases or pullunases for the complete hydrolysis of the starch 3 . These starch hydrolytic enzymes comprise 30% of the world’s enzyme consumption 4 . Thus, α-amylases are extensively used in sugar, textile, alcohol and paper industries. Further, they are employed in food industry for baking, brewing, preparation of digestive aids, production of cakes, fruit juices and starch syrups. In addition, they are used in sewage treatment for reducing the disposable solid content of sludge 5,6 and as detergents 7 . Soil is selected as a source for obtaining desirable amylase producing organisms, because it is rich source of diverse group of microorganisms. Further its wide availability, ease of processing and cost effectiveness also plays a role. Sugar processing includes gelatinization of the starch slurry which is achieved by heating starch with water at temperatures around 100°C, due to insolubility of starch at lower temperatures 8 . Dissolution of starch granules forms a viscous suspension, which poses serious problems with mixing and pumping 9,10,11 . This is overcomed with liquefaction which is brought about by thermostable α-amylases 12,13 , which can act at temperatures around 70-100°C depending on the temperature profile of the α-amylase 10 . Both fungal and bacterial systems are widely used in the production of α- amylases under submerged fermentation (SmF). With the advent of Solid State Fermentation (SSF), production of industrial enzymes received lot of importance. Solid state fermentation is of special importance where the crude fermented product can be directly used as the enzyme source 14 . Thermostable α-amylases have been produced under both submerged 15,16 and solid state fermentations 17,18,19 . Usage of SSF systems effectively overcomes several problems and the yield is several times higher and is cost- effective 20 . The present study deals with the isolation of Aspergillus flavus colonies, production of α-amylase under solid state fermentation using various substrates such as sugarcane bagasse, wheat bran, mollasses bran, rice bran, maize meal and optimizing the conditions necessary for increased production of amylase. MATERIALS AND METHODS Collection of Sample: Soil sample was collected in and around The Oxford College of Science, HSR layout, Bangalore, using pre-sterilized zip lock cover and sterile spatula. Precautionary measures were

Transcript of Shruthi SD et al. IRJP 2012, 3 (8) OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE...

Page 1: Shruthi SD et al. IRJP 2012, 3 (8) OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS Mamatha J, Suresh V, Vedamurthy AB, Shilpi B and Shruthi

Shruthi SD et al. IRJP 2012, 3 (8)

Page 135

INTERNATIONAL RESEARCH JOURNAL OF PHARMACY www.irjponline.com ISSN 2230 – 8407

Research Article

PRODUCTION OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION

WITH OPTIMUM CONDITIONS Mamatha J, Suresh V, Vedamurthy AB, Shilpi B and Shruthi SD*

P.G. Department of Biotechnology, The Oxford College of Science, Bangalore 560102, Karnataka, India

Article Received on: 18/06/12 Revised on: 22/07/12 Approved for publication: 19/08/12 *Email: [email protected] ABSTRACT α-amylases are ubiquitous enzymes produced by plants, animals and microbes, where they play a dominant role in carbohydrate metabolism. In spite of the wide distribution of amylases, microbial sources, namely fungal and bacterial amylases, are used for the industrial production due to advantages such as cost effectiveness, consistency, less time and space required for production and ease of process modification and optimization. Filamentous fungi are known to be prolific producers of extracellular proteins; they are widely exploited for the production of different enzymes including a-amylase. SSF is generally defined as the growth of microorganisms on moist solid substrates with negligible free water, which is preferred than SmF because of simple technique, low capital investment, lower levels of catabolite repression, end- product inhibition, low waste water output, better product recovery and high quality production. Different substrates such as wheat bran, mollasses bran, rice bran, maize meal and sugarcane bagasse were used; out of which sugarcane bagasse has been reported to produce promising results. Different carbon and nitrogen supplements were given which increased the yield of the enzyme and optimized the pH as 6.0 and temperature 300C. Thus the maximum production of amylase was observed at optimized conditions, which can be employed in large scale. Keywords: α-amylase, A. flavus, sugarcane bagasse, pH, supplement, temperature INTRODUCTION Microbial starch utilization is responsible for one of the largest material flows in the biosphere and is of interesting relation to analysis of carbon flux at both local and global scales. The importance of microbial starch and cellulose utilization in natural environments is further enhanced by the status of ruminants as a major source of dietary carbon. Microbial cellulose and starch utilization is also an integral component of widely used processes such as anaerobic digestion and composting1. A promising strategy for efficient utilization of the resources is the microbial hydrolysis and fermentation of waste materials rich in starchy substances and of the resultant reducing sugar for production of desired metabolites or biofuel1. Effective bioconversion processes of starchy materials depend mainly on the good sources of enzymes, the nature of starchy substances and the optimal conditions for production and catalytic activity of the enzymes2. Fungal α-amylase is preferred for use in formulations for human or animal consumption involving applications under acidic conditions and around 37°C. Similarly, due to its biocompatibility, fungal amylases are preferred in baking and food processing. With the advent of new frontiers in biotechnology, the spectrum of amylase application has expanded into many other fields, such as clinical, medical and analytical chemistry. To develop an efficient enzyme based process, prior knowledge of optimum growth conditions, various fermentation parameters, purification strategies and properties of the biocatalyst is of most importance. α-amylases (EC 3.2.1.1, endo-1,4-α-D-glucan glucohydrolase) are endo-acting enzymes which randomly hydrolyze α-1,4-glycosidic bonds between adjacent glucose units in a starch polymer leading to the formation of linear and branched oligosaccharides. They are usually used in synergy with glucoamylases or β-amylases or pullunases for the complete hydrolysis of the starch3. These starch hydrolytic enzymes comprise 30% of the world’s enzyme consumption4. Thus, α-amylases are extensively used in sugar, textile, alcohol and paper industries. Further, they are employed in food industry for baking, brewing, preparation

of digestive aids, production of cakes, fruit juices and starch syrups. In addition, they are used in sewage treatment for reducing the disposable solid content of sludge5,6 and as detergents7. Soil is selected as a source for obtaining desirable amylase producing organisms, because it is rich source of diverse group of microorganisms. Further its wide availability, ease of processing and cost effectiveness also plays a role. Sugar processing includes gelatinization of the starch slurry which is achieved by heating starch with water at temperatures around 100°C, due to insolubility of starch at lower temperatures8. Dissolution of starch granules forms a viscous suspension, which poses serious problems with mixing and pumping9,10,11. This is overcomed with liquefaction which is brought about by thermostable α-amylases 12,13, which can act at temperatures around 70-100°C depending on the temperature profile of the α-amylase10. Both fungal and bacterial systems are widely used in the production of α-amylases under submerged fermentation (SmF). With the advent of Solid State Fermentation (SSF), production of industrial enzymes received lot of importance. Solid state fermentation is of special importance where the crude fermented product can be directly used as the enzyme source14. Thermostable α-amylases have been produced under both submerged15,16 and solid state fermentations17,18,19. Usage of SSF systems effectively overcomes several problems and the yield is several times higher and is cost-effective20. The present study deals with the isolation of Aspergillus flavus colonies, production of α-amylase under solid state fermentation using various substrates such as sugarcane bagasse, wheat bran, mollasses bran, rice bran, maize meal and optimizing the conditions necessary for increased production of amylase. MATERIALS AND METHODS Collection of Sample: Soil sample was collected in and around The Oxford College of Science, HSR layout, Bangalore, using pre-sterilized zip lock cover and sterile spatula. Precautionary measures were

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taken to minimize the contamination. The soil sample was mixed well and processed on the same day. Isolation of Amylolytic Fungi: The amylase producing fungal strains were isolated using serial dilution and spread plate technique on Potato Dextrose Agar medium at 27°C for 3 to 5 days. Identification of the Isolates: The fungal isolates obtained were maintained on PDA slants and were refrigerated at 4°C for further use. Study of colony morphology of the isolated cultures was carried out. Lactophenol cotton blue staining was performed and the slides were observed under microscope. Screening of Isolates for Amylase Production: Screening of the fungal isolates for the amylase production was carried out as below. Starch Agar plates were prepared and inoculated with the single spore inoculum of the fungal isolates. The plates were incubated at 27°C for 3 days. Following incubation, the plates were flooded with iodine solution and looked for clear zone around the fungal growth. Selection of the Solid Substrate: Commercial quality wheat bran, mollasses bran, rice bran, maize meal and sugarcane bagasse procured from the local market were used as solid substrates and their effect on the production of amylase was determined. 5 grams of these solid substrates were weighed individually and placed in petri dishes. 10 ml of distilled water was added to the solid substrates to maintain the moisture; plates were wrapped in aluminium foils and autoclaved. Plates were allowed to cool and 5 ml of the spore suspension of the fungi was added. The entire content of the plates were mixed uniformly with the help of sterile spatulas for uniform distribution of the spores. Plates were incubated at 27°C for 5 days. Analytical Methods: At the end of the fermentation process, the solid biomasses were taken in a pestle and mortar and ground with 50 ml of distilled water. The entire slurries were then centrifuged at 5000 rpm at 4°C for 30 mins. The supernatants were collected and the amylase enzyme assay was carried out using Dinitro Salicylic acid method. Amylase Assay: The culture supernatants were collected separately. With the help of a micropipette, 0.5 ml of each culture supernatant was transferred into different test tubes. 1 ml of 1% starch (S.D. Fine Chem Ltd., Mumbai) solution was added to it. The contents were mixed well and then incubated for 30 mins at 37°C. Released reducing sugar was measured using DNS method and glucose was taken as standard. 3 ml of DNS reagent was added to the incubated tubes and kept for boiling in a boiling water bath for 5 mins, 1 ml of Rochelle’s Salt solution was added after cooling and colour intensity was read at 510 nm. A standard graph was plotted and the enzyme activity was calculated. One unit of enzyme activity was defined as the amount of enzyme required to liberate µg of glucose per minute under the standard assay conditions. The tube showing the highest O.D value, following DNS activity at 510 nm was considered as the best solid substrate. The best solid substrate was selected and used in subsequent experiments. Selection of the Carbon Supplement: The best solid substrate was supplemented with different carbon sources like soluble starch, sucrose, lactose, maltose, dextrose, fructose and glucose at a concentration of 1% (w/w). Moisture content of the plates was maintained as mentioned earlier. Similar inoculation and incubation procedures were followed as above. Following incubation,

DNS activity was performed for the determination of enzyme assay. Selection of the Nitrogen Supplement: The best solid substrate, with the best carbon supplement was supplemented with different nitrogen sources like peptone, tryptone, urea, yeast extract, sodium nitrate and ammonium sulphate at a concentration of 1% (w/w). Moisture content of the plates, inoculation, incubation and determination of enzyme assay procedures were followed same as above. Selection of the Optimal pH: The best solid substrate, with the best carbon and nitrogen supplement was subjected to the effect of different pH, since pH has a profound role to play in the production capabilities of any organism. Different range of pH, ranging from 4 to 8 with an increment of one unit was considered. For maintaining the pH of the media, the water used for maintaining the moisture and the preparation of the inoculum was adjusted to the respective pH values. Following incubation, the DNS activity was performed for the determination of enzyme assay. Selection of the Optimal Temperature: The solid substrate with the carbon and the nitrogen supplement and the optimal pH being set was subjected to the effect of different temperatures. 10, 25, 30, 35, 40, 50, 60, 70 and 80ºC were selected for the production of amylase at low, moderate and high temperature conditions. Following the inoculation of the organism on to the media the plates are kept at different temperatures for an incubation period of 5 days. Following incubation, DNS activity was performed for the determination of enzyme assay. Production of Amylase Under Optimum Conditions: On the basis of the results obtained with all the optimum parameters, viz. sugarcane bagasse containing soluble starch and yeast extract as supplements (1%w/w) was inoculated with the spore suspension of Aspergillus flavus. pH was maintained at 6, incubation temperature of 25°C and incubation period of 5 days; the production of amylase were observed. Following incubation, DNS activity was performed for the determination of enzyme assay of A.flavus growing on optimised media. Protein Assay: Protein was determined by the method of Lowry et al. with crystalline Bovine Serum Albumin (BSA) as the standard. For protein estimation, the working standard was pipetted out as 0.2, 0.4, 0.6, 0.8 and 1 ml of BSA into a series of test tubes. 0.5 ml of the enzyme sample extract was pipetted out into another test tube. The volume was made up to 2 ml in all test tubes, with distilled water. A tube of 2 ml distilled water served as the blank. 5 ml of Reagent C was added to all tubes including the blank. The contents of the tubes were mixed and allowed to stand for 10 minutes at room temperature. Then 0.5 ml of Reagent D (Folins-Ciocalteau Reagent) was added, mixed well and incubated at room temperature in the dark condition for 20 mins. The colour intensity was read at 660 nm to estimate the amount of total protein present. Partial Purification of Enzymes: (i) Ammonium Sulphate Precipitation: The crude sample (enzyme extract) was collected by centrifuging the broth at 5000 rpm for 30 mins at 4°C. The supernatant was transferred in a sterile chilled centrifuge tube and an equal volume of 45% saturated ammonium sulphate solution was added to it. The contents were mixed thoroughly and kept for precipitation at -20°C, over night. The mixed contents were centrifuged again at 5000 rpm for 35 mins at

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4°C. The pellet was collected and suspended in phosphate buffer. (ii) Dialysis: Dialysis tube of suitable diameter was selected and cut to a suitable length able to contain 3 ml volume. The tube was boiled for 10 mins in 100 ml of 2% sodium carbonate solution. The solution was discarded and the tube was boiled 3 times in distilled water for 10 mins. The tube was then boiled in 100 ml of 0.05% EDTA for 10 mins. The end of Dialysis bag was sealed with a knot and the sample was loaded in the bag. The bag was tied at the other end and placed in beaker containing 0.01X PBS. The contents of the beaker were then agitated with magnetic stirrer at 4°C for 24 hours. The partially purified protein was collected and stored at 4°C. RESULTS AND DISCUSSION Screening of Isolates for Amylase Production: Following the serial dilution and pour plate technique 11 colonies of A. niger, 7 colonies of A. flavus, 4 colonies of A. oryzae and 2 colonies of Penicillium were obtained. The pure cultures of fungal isolates were tested for their ability to produce amylase. When grown on the starch agar plates and incubated for 3 days varied degree of starch utilisation was seen. All the fungal isolates showed zone of clearance when iodine was added. Based on the zone of clearance it was found that A. flavus produced the highest level of amylase, which was followed by A. niger, A. oryzae and the least production was observed from Penicillium. The results of which are shown in table 1. Based upon the results of the initial screening, A. flavus was selected as the organism of choice for the further proceedings of the study. Media Optimization of Solid Substrate: In SSF, the selection of a suitable solid substrate for a fermentation process is a critical factor and thus involves the screening of a number of agro- industrial materials for microbial growth and product formation. In our study, all the substrates supported growth and enzyme formation by the culture, while sugarcane bagasse proved superior to the other substrates. A high titre of amylase activity was obtained in a medium containing sugarcane bagasse as the substrate. The order of the substrate suitability was sugarcane bagasse, wheat bran, mollasses bran, rice bran and maize meal as shown in table 2. Optimization of Carbon Source: The influence of supplementary carbon sources was studied. Of the carbon sources tested, soluble starch increased the amylase production followed by sucrose. The order of the substrate suitability was soluble starch, sucrose, lactose, maltose, dextrose, fructose and glucose as shown in fig 1. Optimization of Nitrogen Source: When sugarcane bagasse was supplemented with 1% (w/w) peptone, tryptone, urea, yeast extract, sodium nitrate and ammonium sulphate separately as an organic nitrogen source, along with 1% of soluble starch as supplementary carbon, the highest enzymatic activity was observed for yeast extract at 27°C for an incubation period of 5 days (fig 2). Optimization for Different pH: Each microorganism has a minimal, a maximal and an optimal pH for growth. Effect of pH on the amylase production and the enzyme activity was determined and it was found that the selected organism showed the maximum enzyme activity at pH 6.0, using sugarcane bagasse, soluble starch and yeast extract as the sources of carbon and nitrogen supplements respectively. The results of which are shown in fig 3.

Optimisation of the Fermentation Temperature: Temperature has a profound role to play in the amount of the enzyme produced. When 10, 25, 30, 35, 40, 50, 60, 70 and 80ºC were selected for the production of amylase at low, moderate and high temperature conditions, it was found that the optimal temperature for the enzyme produced by the A. flavus isolate is 30°C, with maximum enzyme activity as shown in fig 4. Production and Partial Purification of Amylase Under Optimised Conditions: The maximum productivity of amylase and the highest activity of the crude enzyme were achieved by utilising sugarcane bagasse as the solid substrate for 5 days at 300C, pH of 6.0 with soluble starch and yeast extract as supplements. The enzyme activity after the ammonium sulphate precipitation and dialysis were recorded as 21.76 µg/min and 25.05µg/min respectively (table 3). Estimation of protein done by Lowry’s method is presented in table 4. The appearance of different solid substratums before and after inoculation with A. Flavus is shown in fig 5. Whereas fig 6 depicts the produced amylase on bagasse under different temperatures, with starch supplement and with yeast extract supplement. SSF constitutes an interesting alternative since the metabolites so produced are concentrated and purification procedures are less costly21,22,23. In the earlier studies sugarcane bagasse has been reported to produce promising results24,25. In our study results indicate that sugarcane bagasse has proved to be the best solid substratum might be because of the high moisture content in the fibres and also presence of satisfactory amount of residual sugars. Other solid substrates had less amount of water content in them which did not aid in the penetration of the fungal hyphae and resulted in less utilisation of the nutrients and hence resulted in production of less amount of the enzyme. Our study proved that soluble starch as a carbon supplement increased the yield of the enzyme and better enzyme activity when compared to the other used sugars. Similar results have also been found by Chandra et al., 26 who found that carbon sources such as galactose, tarch and insulin have been reported as suitable substrates for the production of amylases by B. Licheniformis and Bacillus species. Starch and glycerol are known to increase enzyme production27,28. Soluble starch being the best substrate for the production of a-amylase by B. stearothermophilus is reported29. Earlier Pederson and Nielson30 had found that Yeast extract along with ammonium sulphate gave significant enzyme productivity by A. oryzae. Our results correlate with those found by Nguyen et al., 31 who found out that yeast extract also resulted in significant amylase yield along with L-asparagine and proved to be a promising nitrogen sources for a-amylase production by T. lanuginosus. In our study it was found that the best pH for the production of amylase under solid state condition is 6.0. Earlier studies have revealed that fungi required slightly acidic pH and bacteria required neutral pH for optimum growth. pH is known to affect the synthesis and secretion of a-amylase just like its stability32. Similar results were obtained for other fungi of Aspergillus sp. such as A. oryzae, A. ficuum and A. niger where they gave significant yields of α-amylase at pH 5.0–6.0 in SmF 33,34. α-Amylase producing yeast strains such as S. cerevisiae and S. kluyveri exhibited maximum enzyme production at pH=5.0. The influence of temperature on amylase production is related to the growth of the organism. Hence, the optimum temperature depends on whether the

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culture is mesophilic or thermophilic. Among the fungi, most amylase production studies have been done with mesophilic fungi within the temperature range of 25–37 °C. Our result is in perfect accordance with the results obtained by other workers, where raw starch degrading α-amylase was produced by A. ficuum at 30°C35. CONCLUSION α-Amylases are one of the most widely used enzymes required for the preparation of fermented foods. With the increase in its application spectrum, the demand for the enzyme with specificity is increased. Research is focused on developing thermotolerant and pH tolerant α-amylase from microbes, modifying them genetically or applying site-directed mutagenesis to acquire desired properties in the enzyme. Commercially most of the production of α-amylase is carried out in submerged fermentation, but solid-state fermentation is being looked at as a potential tool for its production, especially applying agroindustrial residues as substrate. The production of α-amylases by SSF has several advantages: production at high enzyme titres, stability in a range of temperature and pH being some of them. These, along with the economics of the production make SSF the ideal choice for the production of α-amylases. Needless to say, these techniques should be of valuable importance to various amylase intensive industries like food-processing, textiles and detergents. However, major hurdles remain in the commercialization of the technology such as online measurement and control of temperature, pH, aeration and moisture content because the production of enzymes in SSF is highly dependent on these environmental factors. Further studies aiming in this direction should be undertaken. REFERENCES 1. Hao YY, Brackeit RE. Pectinase Activity of Vegetable Spoilage

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TABLE 1: RESULTS OF INITIAL SCREENING OF AMYLASE

PRODUCTION BY FUNGAL ISOLATES Sl. No. Isolates Zone of Clearance

(in mm) 1 A. niger 9 2 A. oryzae 6 3 A. flavus 11 4 Penicillium 5

TABLE 2: EFFECT OF SOLID SUBSTRATE ON ENZYME

PRODUCTION Sl.No Solid substrate OD at

540nm Enzyme Activity

(µg/min) 1. Mollasses bran 0.860 11.46 2. Maize meal 0.827 11.02 3. Rice bran 0.849 11.32 4. Sugarcane

bagasse 1.173 15.64

5. Wheat bran 0.895 11.93

Page 5: Shruthi SD et al. IRJP 2012, 3 (8) OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS Mamatha J, Suresh V, Vedamurthy AB, Shilpi B and Shruthi

Shruthi SD et al. IRJP 2012, 3 (8)

Page 139

TABLE 3: O.D AND ENZYME ACTIVITY AFTER DIFFERENT LEVELS OF PURIFICATION

Sl.No Pectinase enzymes OD at 540 nm Enzyme Activity(µg/min) 1. Crude enzyme 1.523 21.64 2. Ammonium sulphate precipitate of

enzyme 1.632 21.76

3. Dialyzed enzyme 1.879 25.05

TABLE 4: O.D VALUES FOR PROTEIN AND PARTIALLY PURIFIED ENZYME AT DIFFERENT STAGES

Test tubes

BSA (ml)

Conc. of BSA (μg)

Distilled water (ml)

Alkaline copper reagent

Incu

bate

for 1

0 m

in a

t roo

m te

mpe

ratu

re FC reagent

Incu

bate

in d

ark

cond

ition

for 2

0 m

inut

es OD at

660 nm

Blank 1 2 3 4 5

Unknown (0.5ml)

Crude sample (0.5 ml)

Ammonium sulphate ppt sample (0.5 ml)

Dialyzed sample(0.5ml)

0 0.2 0.4 0.6 0.8 1 - - - -

0 200 400 600 800

1000 - - - -

2 1.8 1.6 1.4 1.2 1.0 1.5

1.5

1.5

1.5

5ml

0.5ml

0 0.218 0.366 0.526 0.648 0.835 0.418

0.415

0.216

0.229

Fig 1: Graph Showing Effect of Carbon Sources on Enzyme Production

Fig 2: Effect of Different Nitrogen Sources on Enzyme Production

Fig 3: Effect of Different pH on Enzyme production

Fig 4: Effect of Different Temperature on Enzyme Production

Fig 5: Different Solid Substratum Before and After Inoculation with

A. Flavus

Page 6: Shruthi SD et al. IRJP 2012, 3 (8) OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS Mamatha J, Suresh V, Vedamurthy AB, Shilpi B and Shruthi

Shruthi SD et al. IRJP 2012, 3 (8)

Page 140

Fig 6: Amylase Production on Bagasse Under Different Temperatures (A and B); with Starch Supplement (C) and with Yeast Extract

Supplement (D).

Source of support: Nil, Conflict of interest: None Declared IRJP is an official publication of Moksha Publishing House. Website: www.mokshaph.com. All rights reserved.