Comparative phytochemical profiling of Alysicarpus heyneanus [Wight & Arn.] and Alysicarpus heyneanus var. ludens [Baker] A. Pramanik & Toth Using HRLC-MS

Abstract

The genus Alysicarpus (Fabaceae) is taxonomically complex due to morphological variability, necessitating integrative approaches for species delimitation. This study presents a comparative phytochemical and micromorphological profiling of Alysicarpus heyneanus [Wight & Arn.] and Alysicarpus heyneanus var. ludens [Baker] A. Pramanik & Toth. High-resolution liquid chromatography-mass spectrometry (HRLC-MS) of leaf extracts revealed distinct metabolite spectra between the taxa. Both shared major bioactive compounds, such as Apiin, Quercitrin, and fatty acid esters, which confer antioxidant, antimicrobial, and hypocholesterolemic properties. However, A. heyneanus uniquely exhibited Lucenin, Stigmasterol, and a vitamin B analog, while A. heyneanus var. ludens contained Chaulmosulfone, Toosendanin, and Ergosta-5, 7, 22-trien-27-ol, highlighting potential chemotaxonomic markers. Micromorphological analyses further supported differentiation, with significant variation in stomatal subsidiary cell size and trichome morphology. A. heyneanus displayed long, straight trichomes with sharp apices, whereas A. heyneanus var. ludens exhibited shorter, curved trichomes with blunt tips. These findings highlight the complementary roles of phytochemical and micromorphological traits in resolving taxonomic ambiguities and contribute to an understanding of species diversity within Alysicarpus. Moreover, the bioactive metabolites identified suggest promising pharmacological applications, particularly in antioxidant, antimicrobial, and anti-inflammatory therapies. This integrative approach strengthens the taxonomic framework of Alysicarpus and provides baseline data for future molecular, pharmacognostic, and phylogenetic studies.