Vol. 10, Issue 12 (2021)

Author(s):
Abhishek Chitranashi, Ranjeet Ranjan, DV Bhargav, Anshif Ali and Vinutha T

Abstract:
Despite its high nutritional value (9-11 percent protein, 6% fat, micronutrients like iron and zinc), and high calorie content (361 kcal/100 gm), the pearl millet crop is not generally consumed owing to rancidity in the flour, even when kept for a short period of time (less than 30 days). Lipase, lipoxygenase (LOX), polyphenol oxidase, and peroxidase are four enzymes that produce enzymatic rancidity. Lipase degrades lipids to produce free fatty acids, which serve as a substrate for LOX, which catalyzes the reaction to produce hydroperoxides, and then leads to the formation of aldehydes, ketones, and polymers of hydroperoxide, all of which are responsible for the development of off odors and ultimately rancidity. Based on substrate selectivity and the generation of several forms of hydroperoxides, the LOX 2 isoform was chosen for this investigation to investigate its effectiveness in preventing flour rancidity utilizing various treatments. The transcript produced from the transcriptome data was 1.411 kb long and included 921 amino acids, according to bioinformatics analysis. The cytoplasmically confined LOX 2 protein has 45 alpha helices, 74 beta turns, and 5 domains as identified using PDBsum. According on Cys REC analysis, the most likely pair to form a disulfide bond is located between positions 5-151, 202-915, and 209-299. The catalytic residue in LOX 2 was anticipated to be Asn⁷²⁰, whereas amino acid residues His⁵²⁵ His⁵³⁰, His⁷¹⁶, Asn⁷²⁰, and Ile⁸⁶⁴ are involved in the formation of coordinating bonds with iron atoms. The amino acid residues His⁵⁸², His⁵⁸⁷, His⁷⁷⁴, and Asn⁷⁷⁸ are implicated in the ligand binding site, according to the 3D ligand binding tool.