Quantitative Analysis of Total Free Amino Acids and Their Pharmacological Implications in Wild Solanaceae Species from Menal Forest, Rajasthan, India

Abstract

This study assesses the total free amino acid content in five wild Solanaceae species—Datura fastuosa, Datura innoxia, Physalis angulata, Physalis minima, and Solanum virginianum—collected from the Menal Forest region of Chittorgarh, Rajasthan. Using the ninhydrin colorimetric method following acid hydrolysis, both interspecific and organ-specific variations were observed. Among the species, Datura innoxia exhibited the highest amino acid concentrations in leaves (68.09 mg/g), stems (54.07 mg/g), and roots (35.08 mg/g), suggesting strong metabolic activity and adaptive responses to semi-arid conditions. Solanum virginianum and Datura fastuosa also showed substantial foliar amino acid levels, supporting their traditional use in treating liver disorders, infections, and neurological issues. In contrast, Physalis angulata and Physalis minima had lower amino acid contents, particularly in roots and stems, although they retain medicinal value due to other active compounds like withanolides and flavonoids. Overall, leaves consistently recorded the highest amino acid levels across all species, underlining their role in biosynthesis. The findings highlight the nutritional and therapeutic significance of these underutilized wild taxa, reinforcing their relevance in pharmaceutical and nutraceutical applications.