Assessment of genotoxicity and acute oral toxicity of a standardized Ocimum tenuiflorum extract (Holixer^TM)

Ocimum tenuiflorum, commonly referred to as holy basil or Tulsi, has a long history of use in traditional medicine systems, particularly Ayurveda, due to its various health benefits, including anti-inflammatory, antioxidant, and adaptogenic properties. In contemporary contexts, this plant is progressively incorporated into dietary supplements and nutraceuticals. Given its widespread use and potential health beneficial properties, it is imperative to scientifically evaluate the safety of Ocimum tenuiflorum. This study presents comprehensive safety assessments of a standardized extract of Ocimum tenuiflorum. We conducted a series of genotoxicity studies, including the bacterial reverse mutation test (BRMT), in-vitro mammalian chromosomal aberration (CA) test, and in-vivo mammalian erythrocyte micronucleus (MN) test in Swiss Albino mice. Additionally, an acute oral toxicity study was performed using Sprague Dawley rats, adhering to OECD guidelines in a GLP-compliant laboratory. The results showed no mutagenic effect with O. tenuiflorum extract up to a dose of 5000 µg/plate in BRMT. The results of CA test revealed the non clastogenic activity of O. tenuiflorum extract up to a dose of 500 µg/mL with and without metabolic activation (S9). Ocimum tenuiflorum extract was found to be non-clastogenic at the highest tested dose of 2000 mg/kg bodyweight in invivo MN test. In acute oral toxicity study, O. tenuiflorum extract was found to be safe up to 5 g/kg bodyweight in Wistar rats. Collectively, these findings suggest that Ocimum tenuiflorum extract is non-genotoxic and safe for oral consumption up to 5000 mg/kg body weight in Sprague Dawley rats.