Saponins From The Roots Of Securidaca Inappendiculata Hassk

Securidaca inappendiculata Hassk is a traditional Chinese herbal medicine, belonging to the Polygalaceae family, mainly distributed in Yunnan, Guangxi, Guangdong, and Hainan provinces of southern China and the tropical regions of Asia. The roots of S. inappendiculata are used as an anti-inflammatory, antibacterial, and antirheumatism agent in China. Oligosaccharide esters, benzophenones, and hemiterpenoic acid glycoside are already isolated from it, and some saponins obtained from the plant also have been reported. Modern pharmacological evaluations revealed that triterpene saponins from roots of S.inappendiculata exhibited anticancer activities, and triterpenoid Saponins from Polygala tenuifolia showed neuroprotective effects. In continuation of our research, we have examined the saponin fraction of the roots of S.inappendiculata. This paper reported the isolation and the structural elucidation of three new triterpene saponins and five known triterpene saponin with presenegenin as aglycon isolated from S.inappendiculata by means of various chromatographic techniques such as silica gel, MPLC, preparative HPLC, and semi-preparative HPLC. Their chemical structures were identified as scurioside C(1), scurioside D(2), scurioside E(3), polygalasaponin XLIV(4), securioside B(5), 3-O-?-D-glucopyranosyl presenegenin 28-O-?-D-xylopyranosyl-(1?4)-?-Lrhamnopyranosyl-(1?2)-[?-D-glucopyranosyl-(1?3)]-4-O-[(E/Z)-3,4-dimethoxycin namoyl]-?-D-fucopyranosyl ester(6/7), 3-O-?-D-glucopyranosyl presenegenin 28-O-?-L-arabinopyranosyl-(1?3)-?-D-xylopyranosyl-(1?4)-?-L-rhamnopyranosyl-(1?2)-4-O-[(E)-3,4-dimethoxycinnamoyl]-?-D-fucopyranosyl ester(8) on the basis of spectroscopic data analysis and physicochemical properties. Among them, compound 8 was isolated from the plants in genus Securidaca for the first time and compounds 6/7 were isolated from the species for the first time. The cytotoxicity assay and neuroprotection bioassays showed that compounds 1, 5, 6/7, 8 showed moderate cytotoxic activities against Lewis lung carcinoma LLC cells with IC50 values of 45.56, 41.10, 38.17, and 48.92?mol·L-1, respectively; compound 2 have weak cytotoxic activities against Lewis lung carcinoma LLC cells with IC50 values of 85.98 ?mol·L-1, compounds 3/4 no cytotoxic activities against Lewis lung carcinoma LLC cells with IC50 >100?mol·L-1. Compound 5 exhibited moderate cytotoxic activities against human breast cancer MCF-7 cells with IC50 values of 47.93?mol·L-1, Compounds 6/7 exhibited weak cytotoxic activities against human breast cancer MCF-7 cells with IC50 values of 82.24?mol·L-1. Compounds 1, 2, 3/4, 8 have no cytotoxic activities against human breast cancer MCF-7 cells with IC50 > 100 ?mol·L-1. Besides, compounds 1, 2, 3/4, 5, 6/7, 8 exhibited weak neuroprotection activities against neuroblastoma SK-N-SH. This paper summarized the structure characteristics and spectroscopy of the acylated triterpene saponins from the roots of Securidaca inappendiculata Hassk.The problem of separation process and cis-trans isomerism of acylated triterpene saponin were discussed.