Chemical constituents from non-medicinal parts of Stephania kwangsiensis

Stephania kwangsiensis, a vine plant of the Stephaniaceae family, is mainly spread in Guangxi, China. The medicinal part (root tuber) of S. kwangsiensis, “Jin Bu Huan” in Chinese, is often used for sedative, insecticidal, anti inflammatory, anti-tumor, antiviral and antibacterial, as well as for the treatment of Alzheimer’s disease. In order to make full use of the plant resources, clarify its chemical constituents, and find the relevant active compounds, the methanol extracts of non-medicinal parts of this plant were isolated using various chromatographic methods such as positive phase Sephadex LH-20, positive phase silica gel, positive phase polyamide, and MCI gel CHP-20P. The structures of the isolated monomer compounds were determined by MS, 1H-NMR, 13C-NMR, and other spectral data analysis, as well as comparison with relevant literatures. The activities of the isolated compounds from S. kwangsiensis against bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis) and fungi (Fusarium oxysporum) were evaluated using filter paper method. The results were as follows: (1) A total of 10 compounds obtained from the non-medicinal parts of this plant were identified as vomifoliol (1), grasshopper ketone (2), isocorydine(3), 2-O-β-D-glucopyranosyl-D-arabinitol(4),(9S,12S,13S)-trihydroxyoctadeca-(10E,15Z)-dienoic acid (5), magnoflorine (6), corchoionoside C (7), tormentic acid (8), corydine (9) and crebanine (10). Among them, compounds 1, 2, 4, 5, 6, 7 and 8 were isolated from this plant for the first time, compounds 1, 2, 4, 5, 7 and 8 were firstly obtained from this genus plants, and Compound 4 was found from natural products for the first time. (2) At concentration of 6 mg·mL-1, compounds 1, 2 and 5 showed weak antibacterial activities against Escherichia coli; Compound 2 exhibited weak antibacterial activities against Staphylococcus aureus; compounds 3 and 8 displayed weak antibacterial activities against Bacillus subtilis. In conclusion, the non-medicinal parts of Stephania kwangsiensis contain large numbers of active components and have the potential of development and utilization.