Contribution of Phenolic Acid Profiles to the Anti-Adipogenic Activity of Different Mesona procumbens Hemsl. Ethanol Extracts

Background/Objectives: Obesity represents a critical risk factor for various chronic illnesses and metabolic dysfunctions, underscoring the urgency of identifying safe, food-based interventions to curb fat over-accumulation. Mesona procumbens Hemsl. (Hsian-tsao) is a traditional Chinese herb known for its antioxidant and health-promoting properties; however, it remains unclear how its phenolic acid profiles contribute to anti-obesity activity. This research explored the anti-adipogenic potential of various Hsian-tsao ethanol extracts, focusing on how their phenolic profiles influence lipid suppression in 3T3-L1 adipocytes. Methods: Ethanol extracts prepared using different ethanol concentrations were analyzed for total polyphenol content, antioxidant capacity, and phenolic acid profiles. Adipocytes were exposed to 0, 100, and 250 μg/mL of Hsian-tsao ethanol extract for 48 h duration to monitor changes in cell count and intracellular triglyceride levels. Results: Among all fractions, the 40% ethanol extract (40EEHT) possessed the most robust antioxidant capacity and highest polyphenol content, specifically showing enriched levels of caffeic acid, p-coumaric acid, and total phenolic acids. Notably, while 40EEHT influenced cell density at certain concentrations, it significantly and specifically reduced intracellular triglyceride content, indicating a potent inhibitory effect on lipid storage independent of changes in cell number. Comparative analysis using phenolic acid standards revealed that caffeic acid exerted the strongest inhibitory effect on lipid accumulation, suggesting that it is a key contributor to the anti-adipogenic activity of 40EEHT. Conclusions: Collectively, these findings demonstrate that phenolic acid profiles, particularly caffeic acid enrichment, critically contribute to the potential anti-adipogenic effects of specific ethanol extracts of M. procumbens. Therefore, Hsian-tsao ethanol extracts represent a promising natural source for the development of functional ingredients targeting obesity and related metabolic disorders.