Extraction and Characterization of Bioactive Compounds from Kinnow Seeds (Citrus reticulata)

Abstract

During the present study, a study on Kinnow seeds was conducted on their extraction, optimization, and characterization. Kinnow seeds were given three treatments for the extraction of pomace acid treatment, base treatment, and vacuum drying. The three treatment combinations were analyzed for the seeds' moisture, fat, protein, and nitrogen content. On analysis, the acid treatment proved to be an effective method among the three treatment combinations. For estimation of kinnow seed oil extraction yield, the suitability of ultrasound pretreatment in n-hexane solvent as well as enzymatic treatment with cellulase enzyme to extract oil from kinnow seed powders. To further optimization, the effects of ultrasonic time (30–90 min), cellulase enzyme concentration (1–2%) and ultrasound power (20-40%) were investigated using response surface methodology (RSM). The optimum conditions of ultrasound-assisted enzymatic extraction using n-hexane as solvent (UAEE) were found to be 49 min of ultrasonic pretreatment time, cellulase concentration of 1.66%, and ultrasound power of 38% before the incubation process at a temperature of 56 °C for 120 min. The Kinnow seed extracts were evaluated for their total phenolic content (TPC), antioxidant properties with two antioxidant assays DPPH (2, 2 diphenyl-1-picryl hydroxyl) and FRAP (ferric reducing antioxidant power) and antimicrobial (antibacterial and antifungal) properties using different microbial strains.