Effects of oral administration of botanical extracts of oak leaves (Quercus sideroxyla Bonpl.) obtained by infusion and supercritical fluids.

Quercus sideroxyla has been shown to possess a variety of biological activities, including anti-inflammatory, anticancer, and anxiolytic properties. The present study evaluated the acute and subchronic effects of leaf extracts prepared via infusion (Inf) and supercritical fluid extraction (SFE). Male Sprague Dawley rats were divided into seven groups (n = 3) for the acute study: a control group and six groups treated with Inf or SFE extracts at 1000, 2500, and 5000 mg/kg. For the subchronic study, male and female rats (n = 5 groups) received the same treatments for 60 days. A comprehensive analytical approach encompassed blood biochemistry and liver histopathology. No signs of acute toxicity were observed at the limit dose of 5000 mg/kg, indicating that the LD₅₀ is likely higher than this threshold. The results indicated that Q. sideroxyla extracts were well-tolerated in both acute and subchronic response studies, with no significant adverse effects. These findings support the safety of the extracts for human use and highlight the need for further research into their effects across various physiological systems, paving the way for their potential therapeutic applications.