Abstract: The present work is focused mainly on optimizing the extraction of glycoprotein- biosurfactant (BS) produced by Lactobacillus delbrueckii in a biphasic liquid-liquid extraction. The production yield of BS is significantly affected by extraction strategies instead of the whole fermentation process, so it becomes a straightforward approach to enhance BS yield while optimizing various extraction parameters. The tailoring of process parameters for BS extraction was achieved by OFAT (one factor at a time) strategy and partition coefficient (Kd) served as the calculation factor for extraction. The optimal yield of BS (5+0.1 g/L) from CFB (from cell-free broth) was achieved by solvents; chloroform, methanol, and, butanol, 1:2:1 (v/v), from cell-free broth (CFB), 30% (v/v), at pH 3.5, temperature 37°C after extraction time of 60 min. Under optimized conditions, the extraction yield was 78.5% higher and subsequently, a co-current, and counter-current system enhanced the extraction yield by 16% (5.8g/L) and 20% (6.0g/L) respectively. The purity of extracted BS (EBS) was confirmed by UV/Visible spectroscopy and HPLC (High-performance liquid chromatography). The concentration-dependent activity profile of EBS analyzed by ODA (oil displacement area; 50.24+0.3 cm2), DCD (drop collapse diameter; 1.1+0.3 cm), and EI24 (73+0.3%), exhibited enhancement by 60, 52, and 55% respectively as compared to control. Thin-layer chromatography (TLC), FTIR (Fourier Transform Infra-Red) and NMR (Nuclear Magnetic Resonance) techniques confirmed the polymeric glycoprotein (65:35 protein: carbohydrates %) nature of BS.

The aim of this work was to isolate the potent bacterial strains for the production of cellulose enzyme. A total 30 bacterial isolates showed positive results for the cellulase production but highest enzyme activity was shown by isolate JS 14. From the morphological and biochemical reactions, the isolate was identified as Bacillus sp. Cellulase production was studied by this strain using response surface methodology (RSM). A central composite design (CCD) quadratic response surface was applied to explicate the parameters that significantly affected cellulase production in solid substrate fermentation (SSF). The wheat bran concentration and incubation period were significant factors. The process parameters optimized with response surface methodology was wheat bran concentration 400 g/L; pH, 6.5; temperature, 400C and incubation period 5 days when inoculum 10 % (1x107 cells/ ml) was used for cellulase production in SSF. Supplementation of lactose and CMC to the wheat bran medium favored the enzyme formation.

The aim of this work was to study the isolation of glucose oxidase (GOx) from Aspergillus niger in aqueous two phase system consisting of PEG 7500 (150g l-1), potassium phosphate (175 g l-1, K2HPO4 +KH2PO4) and glucose (10 gl-1), the enzyme was partitioned in polymer phase. By sequential extraction GOx (69.2%) was recovered in polymer phase by 11.8 fold purification, giving a yield of 129U mg protein-¹.