Isolation, molecular characterization, immunological and anticoagulatant activities of polysaccharides from frankincense and its vinegar processed product.

Frankincense (FRA), the oily resin consisting of essential oils, boswellic acids (BAs) and polysaccharides, has been used to improve the blood circulation and relieve pain against carbuncles. According to the theory of traditional Chinese medicine, vinegar processed frankincense (VPF) can increase the effects of promoting blood circulation and relieving pain. Existing studies have carried out much on BAs and essential oils. However, the comparative analysis of polysaccharides from FRA and VPF has not been reported. In this paper, two polysaccharides were isolated and purified from FRA and the other two were from VPF, and their structures and physicochemical properties were analyzed. The immunological and anticoagulatant activities of the four polysaccharides were tested in RAW 264.7 cell and Sprague-Dawley rats, respectively. The polysaccharides purified from VPF showed better immunological and anticoagulatant activities than those in FRA. Therefore, polysaccharides may be one of the active substances for the synergistic effect of VPF.

Prenylated isoflavones from the roots of Flemingia philippinensis as potential inhibitors of ß-amyloid aggregation.

In our efforts to find potential agents for the treatment of Alzheimer's disease in naturally occurring compounds, a systematic investigation for the active constituents of Flemingia philippinensis was carried out. Four new prenylated isoflavones, philippinone A-D (1-4), together with six known analogues (5-10), were obtained from the roots of Flemingia philippinensis. Their structures were established through extensive physical and spectroscopic data analysis. All the isolates were evaluated for their inhibitory effect of self-induced Aß aggregation among which compound 5 showed significant Aß aggregation inhibitory ability with the inhibitory rate of 70.56%. The results of molecular docking experiment for compounds 1 and 6 corresponded to that of the thioflavin-T assay. Moreover, the results further clarified the effects of different substituent group of tested compounds on the Aß aggregation inhibition. A preliminary structure-activity relationship is further discussed. Our results suggested that the isoflavonoids may mitigate the progression of AD and compounds 2 and 5 may be a candidate in the treatment of AD.