Pharmacokinetics and Bioavailability of Onion Peel Extracts

Onion peel extracts have been reported to possess various pharmacological activities, including antioxidant, anti-inflammatory, and antimicrobial effects. However, the pharmacokinetics and bioavailability of onion peel extracts have not been fully elucidated. This study aimed to investigate the pharmacokinetics and bioavailability of onion peel extracts in rats. The extracts were administered orally, and the plasma concentrations of the bioactive compounds were determined using HPLC-MS/MS. The results showed that the bioactive compounds in onion peel extracts, including quercetin and kaempferol, were rapidly absorbed and reached peak plasma concentrations within 1-2 hours. The bioavailability of the extracts was found to be moderate, with an absolute bioavailability of 23.4% for quercetin and 17.5% for kaempferol. The extracts were also found to undergo extensive metabolism, with glucuronidation and sulfation being the major metabolic pathways. The results of this study provide valuable information on the pharmacokinetics and bioavailability of onion peel extracts and may be useful in the development of onion peel-based pharmaceuticals and nutraceuticals