Objective: Aim of the present investigation was to optimize the acid protease production from Aspergillus spp. through statistical method in solid state fermentation and to study the inhibitory enzyme kinetics.Methods: To fulfill above mentioned aim, seven solid substrates were screened though using PBD (Plackett-Burman Design) and concentrations of three significant were determined by using one of the Response surface methodologies (RSM), Box-Behnken design (BBD). Inhibitory enzymatic effects were carried by using previously developed models.Results: From PBD, wheat bran, soybean meal, and dried potato peel (DPP) were screened as major influencing nutritional factors for enzyme production. Better optimal values were determined by BBD as wheat bran: 8.841 g, soybean meal: 4.557 g, and DPP: 0.661 g with predicted protease activity as 817.83 U/g (±44.047 U/g). Linear, interactive, and quadratic effects of aforesaid substrates on enzyme activity were formulated by quadratic model through multiple regression model (R2Adj:Adjusted R square = 94.78%; R2Pre:Predicted R square = 98.13%). Partial substrate inhibition to crude acid protease activity was notified with casein concentration higher than 0.4 mmol and inhibitory constant, KN, was computed with previous developed mathematical models. Ratio of reaction rate constants, k4/k2, was found to be 0.233 that had confirmed partial casein inhibition to enzyme velocity. Improved activity and kinetics of caseinolysis make amicable for industrial applications.Conclusion: Quick optimization was performed with statistical methodology over conventional approach. Inhibitory enzyme kinetic studies were important for industrial applications of acid protease.

Objective: Oxidation is a normal process in many biological metabolisms in living beings, but in this technology era radiation, pollution, irregular life style, and unhealthy diet leads to excessive oxidation resulting in imbalance between antioxidants and free radicals in body called oxidative stress, which may result in cardiac problems, diabetes, and carcinogenic diseases. Therefore, exploration of natural antioxidants in flora and fauna is becoming important. In this motive a phytochemical study was taken up on various parts of Pterocarpus santalinus L.f. plant belonging to Leguminosae family to check the presence of antioxidant activity (AA). Methods: The leaves, flowers, fruits, and roots of this plant were extracted with six different organic solvents from polar to non-polar. To estimate the AA of these extracts, four types of antioxidant tests were done on them, namely, α, α – Diphenyl – β – Picryl - Hydrazyl free radical scavenging activity (DPPH RSA) assay, relative reducing power (RRP) assay, Ferric thiocyanate (FTC) assay, and β - carotene bleaching assay with Butylated Hydroxy Toluene (BHT) as synthetic standard. Results: In extraction, Me extracts showed highest yields. Qualitative phytochemical screening has revealed many bioactive components in the Me and Et extracts of plant parts majorly. In DPPH RSA assay, Me extracts of leaves showed RSA activity almost equal to reference standard. In RRP assay, Me floral extracts showed AA higher than standard. FTC and β – Carotene assays showed that Me sample extracts possess good AA than BHT. In FTC assay, lower absorption values specify high AA, whereas in β – Carotene assay, high absorption values indicate high AA of the sample extracts. Conclusion: Among six solvents methanol showed highest extraction efficiency and also revealed highest number of phytochemicals in its extracts. These four AA assays revealed that the methanol extracts of all plant parts, that is., leaves, roots, fruits, and flowers possess better AA compared other solvent extracts.