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Introduction and Aim: Phytic acid (myo-inositol 1, 2, 3, 4, 5, 6- hexakis dihydro­gen phosphate), a storage form of phosphorus is present in legumes, cereals and oilseeds. By forming insoluble complexes with proteins and divalent cations, it serves as an anti-nutrient in animal feed. Phytase (EC 3.1.3.8), a special class of phosphomonoesterases, catalyse the conversion of inorganic phosphate into mono-, di-, tri-, tetra-, and penta-phosphates of derivatives of myo-inositol. It is an important enzyme in food and feed industries. The present study aimed at isolation, molecular identification and optimization of physico-chemical parameters for phytase production by a red pigmented yeast Cystobasidium minutum. Materials and Methods: The phytase activity was estimated by using sodium phytate as substrate and the production of phytase under varied temperature, pH, agitation, incubation time, carbon and nitrogen sources. Results: The results showed maximum activity of 91.86 and 27.13 U/ml at 35°C and pH 5.5. At an agitation speed of 150 rpm and 120h of incubation time the enzyme activity was 18.9 and 21.4 U/ml respectively. Among the carbon sources tested sucrose served for highest enzyme activity of 26.33 U/ml and ammonium sulphate served the sole source of nitrogen and showed an activity of 50.12 U/ml. Conclusion: Cystobasidium minutum (Rhodotorula minutum) produced maximum phytase enzyme in an optimized physical and chemical condition. Hence, from the present investigation, it is found that optimization of physic-chemical conditions may be a promising tool for the growth of organisms and also maximum yield of any metabolite.

Introduction and Aim: Tannase an inducible extracellular microbial enzyme is extensively produced by different fermentation techniques and finds wide applications in food, pharmaceutical and textile industries. The present investigation focused on tannase production from Aspergillus niger through submerged (SmF) and solid-substrate fermentation (SSF) using different media. The enzyme was also induced using tamarind seeds. Methods and Materials: Aspergillus niger was grown in various submerged media such as Tannase screening broth (TSB), Czapek Dox broth (CDB), Sabouraud’s Dextrose broth (SDB) and Potato Dextrose broth (PDB). Among solid substrates wheat bran, ground nut cake, coconut cake and tamarind seed powder used individually and in mixed form. Results: In SmF, the highest tannase activity of 713.6 U/ml was found in TSB, followed by CDB (590.6 U/ml), SDB (465.6 U/ml) and PDB (424.8 U/ml). In all media highest activity was on 4th day while in SDB on 6th day of incubation. Tannase production was also carried out in CDB supplemented with 2% processed tamarind seeds to test for its induction, where the highest (936 U/ml) activity was in raw seeds than in processed seeds. SSF in mixed substrates showed highest activity of 1708.6 U/gds followed by 1278.0, 986.5, 826.3 and 723.6 U/gds in tamarind seeds, wheat bran, ground nut cake and coconut cake, respectively. Conclusion: Tannase enzyme is found to be induced by raw tamarind seed supplemented submerged medium than with processed seeds. In SSF with tamarind seed showed the highest tannase activity indicating that the tannic acid present in raw seeds serve to induce Aspergillus niger for increased production of tannase enzyme.