Phytochemical characterization, antioxidant activity and antihypertensive evaluation of Ocimum basilicum L. in l-NAME induced hypertensive rats and its correlation analysis

by Selleckchem | Jun 05 2023

Ocimum basilicum Linn. (basil) is an aromatic culinary herb that has shown a great potential in therapeutic world. It has many promising pharmacological activities that make it centre for investigations for many researchers. Current study has been planned to determine chemical constituents of basil leaves extracts and their in-vitro and ex-vivo antioxidant and in-vivo antihypertensive potential. GC-MS studies of non-polar extracts showed presence of 75 compounds including monoterpenes, hydrocarbons, sesquiterpenes, triterpenes, phyto-sterols and phthalates. Higher percentages of fatty acids were also identified. The major compounds include linalool (7.65%), terpineol (1.42%), tau-cadinol (13.55%), methyl palmitate (14.24%), palmitic acid (14.31%), linolenic acid (1.30%) and methyl linolenate (17.72%). Electron spray ionization mass spectrometry ESI-HRMS/MS of the polar extracts revealed the presence of alkaloids, phenolic acid, amino acid, coumarin, lignin, flavanoid and terpene derivative. Total phenolic content and total flavonoid content were determined using spectrophotometric technique and calculated as gallic acid equivalents GAE/g dry weight and rutin equivalent RE/g of dry weight respectively. The highest phenolic content and flavonoid content were found in ethyl acetate extract 9.40 mg GAE/g and 15.9 mg RE/g of dry weight. All the extracts showed significant antioxidant activity in DPPH and ABTS cation decolorization assays. Dichloromethane extract possess the highest DPPH scavenging activity, i.e., 64.12% ± 0.23 at concentration of 4 mg/ml. Moreover in ex-vivo studies all the extracts showed prominent effect by inhibiting AAPS induce oxidation in Human erythrocytes being 69.24% ± 0.18 in dichloromethane extract, 64.44% ± 0.04 in ethyl acetate and 53.33% ± 0.09 in acetone extract. The methanol extract of O. basilicum exhibited significant decrease in systolic blood pressure in l-Name induced hypertensive rats at the dose of 50 mg/kg for 28 days. Total phenolic content had a higher linear correlation (r = 0.678) with antihypertensive activity, with a level of significance 95% showing that phenolic compounds in the leaves of the plant has important role in inhibiting l -NAME induced hypertension while flavonoid compounds may play a key role in the antioxidant activities of the plant, through synergism. Conclusively, O. basilicum leaves with bioactive metabolites are a potential source for the development of antihypertensive drugs.

Comments：

The study explores the chemical composition and potential therapeutic properties of Ocimum basilicum Linn. (basil) leaves extracts. The non-polar extracts were found to contain various compounds, including fatty acids, monoterpenes, sesquiterpenes, triterpenes, phyto-sterols, and phthalates, while polar extracts contained alkaloids, phenolic acid, amino acid, coumarin, lignin, flavonoid, and terpene derivatives. The highest total phenolic and flavonoid contents were found in ethyl acetate extract.

All extracts showed significant antioxidant activity in DPPH and ABTS cation decolorization assays, and ex-vivo studies showed the extracts' ability to inhibit AAPS-induced oxidation in human erythrocytes. The methanol extract of O. basilicum exhibited significant antihypertensive activity in l-Name induced hypertensive rats, with a higher correlation observed between antihypertensive activity and total phenolic content.

In conclusion, O. basilicum leaves with bioactive metabolites have the potential to be developed into antihypertensive drugs, with phenolic compounds playing a key role in inhibiting l-Name induced hypertension and flavonoid compounds contributing to antioxidant activities.