Comparative Evaluation of Takhrai (Cymbopogon citratus) Leaf Extracts with Commercial Antioxidants for Oxidative Stress Mitigation in Ruminants Under Heat Stress

This investigation presents a rigorous comparative evaluation of methanolic and hexanoic extracts from Takhrai (<i>Cymbopogon citratus</i>) leaves against commercial antioxidants for mitigating oxidative stress in heat-stressed ruminants. Phytochemical profiling revealed significantly higher concentrations of bioactive compounds in methanolic extracts, particularly ascorbic acid (2.12 ± 0.08 mg/g), sinapic acid (0.71 ± 0.03 mg/g), and apigenin (0.38 ± 0.02 mg/g). Methanolic extracts demonstrated exceptional antioxidant activities (DPPH IC₅₀ = 36.62 ± 0.65 μg/mL), superior erythrocyte protection (hemoglobin oxidation IC₅₀ = 12.06 ± 0.29 μg/mL), and robust Nrf2 pathway activation (HO-1 induction = 3.42 ± 0.17-fold). Metabolomic analyses revealed preservation of glutathione metabolism and attenuation of lipid peroxidation product accumulation. Immunomodulatory assessment demonstrated significant reduction of pro-inflammatory cytokines (TNF-α reduced by 54.3 ± 4.8%) and enhancement of anti-inflammatory mediators following LPS challenge. While storage stability presented limitations at ambient conditions (52.4 ± 3.7% activity retention after 6 months), refrigeration substantially improved preservation (92.3 ± 2.8%). Comprehensive effectiveness ranking across twelve parameters positioned methanolic extracts (mean score 1.7) comparable to vitamin E (1.6) and superior to other interventions. Collectively, these findings establish methanolic Takhrai extracts as promising sustainable alternatives to commercial antioxidants, with particular relevance for ruminant production in tropical regions.