Phytochemical analysis, antioxidant, anti-inflammatory, anti-genotoxic and anticancer activities of different ocimum plant extracts prepared by ultrasound-assisted method

Abstract The genus Ocimum belonging to the family Lamiaceae, have been widely used in traditional medicines for the management of inflammation, dysentery, and chronic diarrhea as well as insect bites. The study aims to evaluate the phytochemistry and pharmacological activities of Ocimum gratissimum (OG), O. basilicum (OB), O. canum (OC), O. kilimandscharicum (OK), O. tenuiflorum (OT), and O. citriodorum (OXC) extracted in an ultrasound-assisted manner. There observed significantly higher polyphenols in OB (246.2 ± 8.0 mg GAE/g) and antioxidant activity in OG terms of DPPH radical (14.73 ± 0.54 μg/mL), ABTS+ radical and hydrogen peroxide scavenging assays (in OB with IC50 values 9.46 ± 0.28 and 6.22 ± 0.13 μg/mL); the most active extract was OB and OG. Similarly, OB, OG and OT were shown to have higher anti-inflammatory properties in terms of nitric oxide scavenging and lipoxygenase inhibition. Further, using the Allium cepa model, the genotoxicity of these extracts were evaluated; however, none of these plants was shown to have any kind of genotoxic potentials till a concentration of 500 μg/mL. Instead, they were able to protect the genotoxic effect of ethyl methyl sulfonate (EMS) in the dividing cells of Allium cepa. Further, these extracts, especially of OG, OT and OB, were found to reduce the proliferation of human breast cancer cells (OB and OC with IC50 values 49.36 ± 1.27 and 53.86 ± 0.96 μg/mL). The study identified the antioxidant, anti-inflammatory, anti-genotoxic and anticancer properties of ultrasound-assisted extracted Ocimum plants, with higher activity in OB and OG species.