Phenotypic and chemotype variation of Andrographis paniculata from different regions in Thailand

Abstract

This study assessed the link between the phenotypic and chemical makeup of the local Andrographis paniculata. The five seed collections came from various parts of Thailand: Kamphaeng Saen (KS), Udon Thani (UT), Chiang Rai (CR), Chiang Mai (CM), and Ratchaburi (RB). They were grown in an open conventional greenhouse under the same conditions: potted and 60% shaded. At the point of commercial harvesting, these plants' phenology and chemical makeup were evaluated (ca. 90 days after planting). The findings showed that UT was morphologically unique and had the maximum edible biomass output (aerial and mature leaf size). Following ethanol maceration at an 80 % (w/w) concentration, the above-ground portions (i.e., the leaves and stem) were examined for bioactive chemicals. The leaf and stem extracts from all samples except KS had the highest lactone content (~14 mg/g extract), it was discovered. Still, it was found that the KS stem extract had the most total phenolics and flavonoids, at 3.22 mg/g and 2.42 mg/g, respectively. According to DPPH and ABTS assay results, phytochemicals from both leaf and stem extracts were capable of having significant antioxidant activity (70%). Chemically, RB had the most 14-deoxy-11,12-didehydroandrographolide (156.98 mg/g extract), while UT and CM only had up to 0.68 mg/g extract of neoandrographolide. The samples' classification revealed a distinct correlation between morphological characteristics and chemical contents. Our research suggests that the various landraces of A. paniculata exhibit differences in phenotypic and chemotypic relationships. In essence, the consumable part count served as a barometer for the quality of the phytochemical components. The main result of this study was the selection of physiological traits that may be applied to future breeding initiatives of the optimal variety with high productivity and greater bioactive(s) content.