Lin_2026_Front.Nutr_13_1783378

INTRODUCTION: Resin glycosides (RGs) found in the aerial parts of sweet potato are health promoting agents that can be reclaimed from the by-products of sweet potato plantation as agriceuticals for combating obesity. However, RGs have complex structural variations across various sweet potato cultivars, along with an unclear structure-activity relationship. To address this gap, nine types of sweet potato leaves were evaluated, including "Shangshu 19", "Xuzi 20-1", "Xushu 24", "Xushu 32", "Yanshu 25", "Blackheart", "Blackie", and two "Beniazuma" samples. METHODS: RG-rich extracts were obtained from sweet potato leaves by using dichloromethane extraction. Pancreatic lipase (PL) inhibitory activity was then determined by a p-nitrophenyl palmitate (pNPP)-based assay. Individual RG profiles were characterized and semi-quantified by UHPLC-Q-TOF-MS/MS, followed by multivariate analysis to evaluate cultivar-dependent variations and identify spectral features associated with PL inhibition. RESULTS: Xushu 32 and Blackheart cultivars exhibited the highest PL inhibitory activities with an Orlistat equivalent (OE) of 2.44 +/- 0.30 and 2.02 +/- 0.10 ng orlistat/microg extracts, respectively. In total, 128 RGs were tentatively identified based on UHPLC-Q-TOF-MS/MS analysis. Multivariate analysis revealed cultivar-dependent differences in RG profiles and identified four RGs as potential marker compounds associated with PL inhibition. All four RGs were pentasaccharides featuring 2-methylbutyric and dodecanoic acid as side chains. Further mechanistic study revealed that long-chain fatty acid esters or a macrocyclic lactone moiety on the RG backbone may play a key role in conferring inhibition. DISCUSSION: Taken together, these findings may serve as valuable guidelines for foodomic analysis of RGs and cultivar selection in developing anti-obesity functional foods derived from agricultural by-products.In addition, we would like to double-check that the formatting of Table 1 is maintained as in the original manuscript we provided. The current proof version includes additional internal table lines that slightly alter the intended meaning of the table.