Geographical Variation in Centella asiatica (L.) Urban: Morphological Adaptations Associated With Distinct Phytochemical Signals and Bioactivity of Extracts.

Centella asiatica (L.) Urban is a medicinal plant whose extract quality can vary with environmental context and associated differences in plant morphology and secondary metabolism. This study examined how geographical variation across three Indonesian agroecological regions (Kediri, Kulon Progo, and Tawangmangu) is associated with morphological variation, qualitative phytochemical profiles, and measured bioactivity of C. asiatica extracts. Comparative analyses revealed distinct region-specific morphological traits that covaried with differences in extraction yield, qualitative phytochemical signals, antioxidant capacity, and photoprotective activity. Among the tested solvent systems, ethanol consistently produced extracts with broader metabolite-class signals and higher measured bioactivity. The high-altitude Tawangmangu accession extracted with ethanol showed the lowest IC50 and the highest SPF values in this dataset, a pattern consistent with the working interpretation of eco-phytochemical association along an environmental gradient. Factorial statistical analyses indicated significant effects of accession, solvent polarity, and their interaction on extract quality and bioactivity. Overall, the findings support the importance of integrating geographical origin and extraction strategy when selecting plant sources for standardized botanical extracts while acknowledging that mechanistic causation was not tested.