Optimization of physico-chemical parameters for biosurfactant production by yeast
dc.contributor.advisor | Sangwan, Seema | |
dc.contributor.author | Sharma, Pankaj | |
dc.date.accessioned | 2017-10-21T06:36:27Z | |
dc.date.available | 2017-10-21T06:36:27Z | |
dc.date.issued | 2017 | |
dc.description.abstract | Commercial production of biosurfactant, a surface-active compound produced by microorganisms such as bacteria, yeast and fungi, is restricted due to increased cost of production which could be lowered down by optimization of production process using high yielding strains. The present investigation was designed to optimize various physical and chemical parameters of biosurfactant production monitored in terms of oil displacement and E24 index, by four promising isolates, YK20, YK21, YK22 and YK32. Among carbon sources, olive oil at 8%(v/v) concentration was optimized as it gave maximum oil displacement of 7.5cm in case of isolate YK32 followed by 6.6cm in case of isolate YK20. Diesel being complex hydrocarbon source was not utilized easily and showed poor biosurfactant production, however it was maximum supported by YK22 which gave maximum oil displacement of 4.5cm after 5 days of incubation. Yeast extract at 1.5%(w/v) concentration yielded maximum biosurfactant as evident from maximum oil displacement of 8.1cm followed by 7.3cm along with an emulsification index of 52.6% and 50.2% in case of isolates YK32 and YK20, respectively. Yeast extract showed most encouraging results with isolate YK22 as its supplementation, approximately doubled the biosurfactant production in first 24h from 1.2-1.9cm to 3.0-3.1cm at different concentrations Sodium chloride concentration at the rate of 3%(w/v) was selected for further studies as it supported oil displacement of 8.8 and 8.1cm given by isolates YK32 and YK20, respectively. Any increased concentration above this level, negatively influenced the biosurfactant production. Biosurfactant production was observed maximum at 30°C as monitored in terms of oil displacement of 8.8cm in case of isolate YK32 and it decreased marginally as the temperature was shifted to either 35°C (5.2cm) or 25°C (7.6cm). An increased temperature to 40°C, however, decreased oil displacement, significantly to 2.5cm. Biosurfactant production appeared to be sensitive to varying pH as evident from an emulsification index as high as 67.3% at pH 6.0 in case of isolate YK32 as compared to 60.2%, 60.1% and 52.4% at pH 5.0, 5.5 and 7.0, respectively. Maximum biomass production, 10.3g/L, was observed at pH 6 in isolate YK32 while a minimum biomass, 6.3g/L was attained at pH 7 in case of isolate YK21. Elimination of shaking at the rate of 150rpm reduced the emulsification index from 63.8% to 30.3%, 58.8% to 34.1% and 60.2% to 30.6%, respectively in case of isolates YK20, YK21 and YK22 after 5 days of incubation. | en_US |
dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810033447 | |
dc.keywords | Biosurfactant, Yeast, Oil displacement technique, Emulsification index, Biomass production, Optimization, Stationary conditions | en_US |
dc.language.iso | en | en_US |
dc.publisher | CCSHAU | en_US |
dc.sub | Microbiology | en_US |
dc.subject | null | en_US |
dc.theme | Optimization of physico-chemical parameters for biosurfactant production by yeast | en_US |
dc.these.type | M.Sc | en_US |
dc.title | Optimization of physico-chemical parameters for biosurfactant production by yeast | en_US |
dc.type | Thesis | en_US |