Optimization of Xylanase Production from Bacillus Sp. Pkd-9 under Solid State Fermentation, Partial Characterization and Application
Deepesh, Panwar (2011) Optimization of Xylanase Production from Bacillus Sp. Pkd-9 under Solid State Fermentation, Partial Characterization and Application. [Student Project Report]
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Abstract
This Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page.
Item Type: | Student Project Report |
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Additional Information: | A tremendous increase in the knowledge of microbial xylanolytic systems has been attained in the past few decades; however, quest of newer and novel microbial sources producing hyper titers of alkalo-thermostable xylanases is still prevalent across many laboratories worldwide. An enrichment and screening process was carried out to select bacteria capable of producing alkalo-thermo stable xylanase. The isolate was identified as Bacillus sp. based on cultural and morphological characters. Xylanase was produced under solid-state fermentation (SSF) using agro industrial residue i.e. wheat bran from Bacillus sp. PKD-9. Maximum (75000.0 IU/g) xylanase production was obtained at 1: 4 ratio of solid substrate-to-moisture, pH 8.0, Inoculum size 5.0% (v/v), 7.5 g substrate/250 ml Erlenmeyer flask. The process of xylanase recovery was also optimized (one at a time and statistical methods). Out of various ionic and non-inonic surfactants, Pluronic F-68 at low concentration (0.24% w/v) enhanced xylanase recovery by 26 % when compared with control without surfactant. Addition of Pluronic F-68 to the solid media in extraction buffer under shaking conditions (200 rpm) at RT for 20-60 min increase enzyme recovery by 14%. Response surface methodology (RSM) showed enhance xylanase recovery from Bacillus sp. PKD-9 fermented wheat bran (98000 IU/g) with increase in shaking time of 10 min and low levels of liquid extractant. The partially purified xylanase from Bacillus sp. PKD-9 was optimally active at pH 8.0 and retained 75.0% of its activity after 25 h of incubation at room temperature in pH range (6.0-10.0). Optimum temperature was found to be 55°C and enzyme had a half life of 60 min and 30 min at 450C and 500C, respectively. Surfactants such as Pluronic F-68, tween-20, 40, 60, and 80 increased xylanase activity up to 26.0% at 0.2% (w/v). Metal ions such as Na2+, Li+, K+, Ba2+ at 5.0 mM concentration stimulated enzyme activity up to 29.0%. The presence of Cu2+, Co2+, and Zn2+ reduced activity (up to 95.0 %) at 10.0 mM level. Hg2+ completely inhibited (up to 98.0%) xylanase activity The Km and Vmax values of partially purified xylanase were 0.071 mg/ml and 32654.0 mol/ml/min for birchwood xylan. Activity of partially purified xylanase from Bacillus sp. PKD-9 was not inhibited by - mercaptoethanol, iodoacetic acid and iodoacetamide. The bio-treatment efficiency of poultry feed by crude enzyme xylanase solution in terms of release of reducing sugars was found to be maximum (81.0 mg/g dry chick feed reducing sugars) after 1 h of incubation at enzyme dose of 200.0 IU/g poultry feed at 37°C. |
Uncontrolled Keywords: | microbial xylanolytic systems, solid-state fermentation, agro industrial residue, Bacillus sp |
Subjects: | 600 Technology > 05 Chemical engineering > 04 Fermentation Technology 600 Technology > 08 Food technology > 16 Nutritive value > 05 Enzymes |
Divisions: | Protein Chemistry and Technology |
Depositing User: | Food Sci. & Technol. Information Services |
Date Deposited: | 08 Jul 2011 04:25 |
Last Modified: | 08 Jul 2011 04:25 |
URI: | http://ir.cftri.res.in/id/eprint/10252 |
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