Optimizing the extraction of protein from Prosopis cineraria seeds using response surface methodology and characterization of seed protein concentrate

摘要

Prosopis cineraria is one of the leguminous trees in arid India, and its pods are known as "Sangri". The study aims to optimize the extraction condition for soluble protein from Sangri seed flour using response surface methodology considering pH (8-12), extraction temperature (30-60 degrees C) and time (1-3 h) as variables. The optimized condition suggested employing the isoelectric precipitation method at pH 9.81 for 100 min at 60 degrees C would lead to the maximum soluble protein of 310 g kg(-1). The molecular weight of the seed protein concentrate (SPC) was found to be 26.5 kDa exhibiting an amorphous nature having a crystallinity index value of 0.97. The denaturation heat (Delta H) for SPC was 238.16 J/g with a transition enthalpy of 11.5 J/g of protein. The solubility of SPC is 41.5% at pH 7. The water and oil holding capacity of SPC were 3.87 g/g and 1.4 g/g, respectively; whereas, the maximum foaming capacity of SPC was 40.5% at pH 12. The total phenolic content in the concentrate was 2.8 mg GAE/g with an antioxidant capacity of 3.0 mg AAE/g. During the extraction, the antinutrients such as tannin, saponin, and phytate content were reduced by 95, 50, and 42%, respectively.