Studies on Photocatalysis by Nano Titania Modified with Non-Metals

The present work aims to prepare visible light responsive anion doped titania via sol-gel precipitation method.The prepared catalysts were characterized by various techniques.The photocatalytic abilities of the prepared catalysts were measured by the degradation of dyes,pesticides,hydrogen production through water splitting reaction and antibacterial study.We also compared the activities of prepared catalysts with pure titania prepared in the laboratory and one of the commercial anatase titania samples.

Development of nitrifying and photosynthetic sulfur bacteria based bioaugmentation systems for the bioremediation of ammonia and hydrogen sulphide in shrimp culture

This thesis entitled Development of nitrifying ans photosynthetic sulfur bacteria based bioaugmentation systems for the bioremediation of ammonia and hydregen sulphide in shrimp culture. the thesis is to propose a sustainable, low cost option for the mitigation of toxic ammonia and hydrogen sulphide in shrimp culture systems. Use of ‘bioaugmentors’ as pond additives is an emerging field in aquaculture. Understanding the role of organisms involved in the ‘bioaugmentor’ will obviously help to optimize conditions for their activity.The thesis describes the use of wood powder immobilization of nitrifying consortia.Shrimp grow out systems are specialized and highly dynamic aquaculture production units which when operated under zero exchange mode require bioremediation of ammonia, nitrite nitrogen and hydrogen sulphide to protect the crop. The research conducted here is to develop an economically viable and user friendly technology for addressing the above problem. The nitrifying bacterial consortia (NBC) generated earlier (Achuthan et al., 2006) were used for developing the technology.Clear demonstration of better quality of immobilized nitrifiers generated in this study for field application.

Production, purification and partial characterization of a novel protease from marine Engyodontium album BTMFS10 under solid state fermentation

Engyodontium album isolated from marine sediment produced protease, which was active at pH 11. Process parameters influencing the production of alkaline protease by marine E. album was optimized. Particle size of <425 mm, 60% initial moisture content and incubation at 25 8C for 120 h were optimal for protease production under solid state fermentation (SSF) using wheat bran. The organism has two optimal pH (5 and 10) for maximal enzyme production. Sucrose as carbon source, ammonium hydrogen carbonate as additional inorganic nitrogen source and amino acid leucine enhanced enzyme production during SSF. The protease was purified and partially characterized. A 16-fold purified enzyme was obtained after ammonium sulphate precipitation and ion-exchange chromatography. Molecular weight of the purified enzyme protein was recorded approximately 38 kDa by SDS-PAGE. The enzyme showed maximum activity at pH 11 and 60 8C. Activity at high temperature and high alkaline pH suggests suitability of the enzyme for its application in detergent industry

Propyl Gallate Synthesis Using Acidophilic Tannase and Simultaneous Production of Tannase and Gallic Acid by Marine Aspergillus awamori BTMFW032

Marine Aspergillus awamori BTMFW032, recently reported by us, produce acidophilic tannase as extracellular enzyme. Here, we report the application of this enzyme for synthesis of propyl gallate by direct transesterification of tannic acid and in tea cream solubilisation besides the simultaneous production of gallic acid along with tannase under submerged fermentation by this fungus. This acidophilic tannase enabled synthesis of propyl gallate by direct transesterification of tannic acid using propanol as organic reaction media under low water conditions. The identity of the product was confirmed with thin layer chromatography and Fourier transform infrared spectroscopy. It was noted that 699 U/ml of enzyme could give 60% solubilisation of tea cream within 1 h. Enzyme production medium was optimized adopting Box–Behnken design for simultaneous synthesis of tannase and gallic acid. Process variables including tannic acid, sodium chloride, ferrous sulphate, dipotassium hydrogen phosphate, incubation period and agitation were recognized as the critical factors that influenced tannase and gallic acid production. The model obtained predicted 4,824.61 U/ml of tannase and 136.206 μg/ml gallic acid after 48 h of incubation, whereas optimized medium supported 5,085 U/ml tannase and 372.6 μg/ml of gallic acid production after 36 and 84 h of incubation, respectively, with a 15-fold increase in both enzyme and gallic acid production. Results indicated scope for utilization of this acidophilic tannase for transesterification of tannic acid into propyl gallate, tea cream solubilisation and simultaneous production of gallic acid along with tannase