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Hibiscusspecies are flowering plants of the Malvaceae family. Hibiscusare widely distributed in tropical and subtropical regions and play an important role not only in ornamental aspects but also traditional medicine. In this study, seven compounds, mukungarrole (1), a new compound and six known flavonoid derivatives (2–7) were isolated from Hibiscus syriacuspollen. Among the isolated compounds, kaempferol (2) and vincetoxicoside B (3) showed antioxidant activity. Additonally, the new compound, mukungarrole (1), along with kaempferol (2) and isorhamnetin-7-O-rhamnoside (5), showed α-glucosidase inhibitory activity and its interaction with α-glucosidase was confirmed using molecular docking analysis. Further comparison of five varieties of Hibiscusspp. showed that all five species contained vincetoxicoside B (3) and kaempferol-7-O-rhamnoside (4) as major components and exhibited antioxidant and α-glucosidase inhibitory activities. However, there was differences in the content of vincetoxicoside B (3) and kaempferol-7-O-rhamnoside (4) and minor components depending on of Hibiscusvariety, which contributed to differences in efficacy. This study proves that H. syriacuspollen and its constituents have antioxidant and α-glucosidase inhibitory potentials and the content and efficacy vary depending on Hibiscusspecies.

Actinidia arguta, commonly called hardy kiwifruit or kiwiberry, has cold-resistant properties and can be cultivated in Asia, including Korea. Seven new triterpenoids (2–4and 8–11) along with eight known triterpenoids were isolated from the leaves of A. argutathrough various chromatographic techniques. The new triterpenoids were defined as actiniargupenes A–C (2–4), actinidic acid derivatives with phenylpropanoid constituent units, dehydroisoactinidic acid (8), and actiniargupenes D–F (9–11), asiatic acid derivatives with phenylpropanoid substituents, on the basis of 1D and 2D NMR and MS data. Among the triterpenoids, those with a phenylpropanoid constituent unit showed inhibitory activity on α-glucosidase, which suggested the importance of the phenylpropanoid moiety. Molecular docking analysis demonstrated the interaction between the 4′-OH group of the phenylpropanoid moiety and α-glucosidase.