Polymyxin B as an inhibitor of lipopolysaccharides contamination of herb crude polysaccharides in mononuclear cells / 中国天然药物

Lipopolysaccharides (LPS) contamination in herbal crude polysaccharides is inevitable. The present study was performed to explore the effect of polymyxin B on abolishing the influence of LPS contamination in mononuclear cells. LPS was pretreated with polymyxin B sulfate (PB) at different concentrations for 1, 5 or 24 h, and then used to stimulate RAW264.7 and mouse peritoneal macrophages (MPMs). The nitric oxide (NO) and tumor necrosis factor-α (TNF-α) in cell culture supernatant, as the indications of cell response, were assayed. Bupleurum chinensis polysaccharides (BCPs) with trace amount contamination of LPS was treated with PB. 30 μg·mL of PB, treating LPS (10 and 1 000 ng·mL in stimulating RAW264.7 and MPMs respectively) at 37 °C for 24 h, successfully abolished the stimulating effect of LPS on the cells. When the cells were stimulated with LPS, BCPs further promoted NO production. However, pretreated with PB, BCPs showed a suppression of NO production in MPMs and no change in RAW264.7. In the in vitro experiments, LPS contamination in polysaccharide might bring a great interference in assessing the activity of drug. Pretreatment with PB (30 μg·mL) at 37 °C for 24 h was sufficient to abolish the effects of LPS contamination (10 and 1 000 ng·mL).

Isolation of an anti-complementary polysaccharide from the root of Bupleurum chinense and identification of its targets in complement activation cascade / 中国天然药物

AIM@#To isolate and characterize the anti-complementary polysaccharide from the root of Bupleurum chinense.@*METHODS@#Bioactivity-guided fractionation and purification was used to obtain the anti-complementary polysaccharide from the hot-water extract of the root of Bupleurum chinense. The polysaccharide was characterized by various chemical and spectral analyses. The anti-complementary activities were evaluated by hemolytic assay in vitro. The action targets were identified in the system with individual complement-depleted sera.@*RESULTS@#A homogeneous polysaccharide BC-PS2 was isolated as an anti-complementary agent. It was identified as a branched polysaccharide with an average molecular weight about 2 000 KDa, composed of Glc, Ara, Gal, and Man in the ratio 3.5 : 2.4 : 2.0 : 1.0, respectively, along with a trace of Rha and Xyl, and only 1.11% of protein. The main linkages of the residues of BC-PS2 include terminal, 1, 6-linked, 1, 3-linked and 1, 3, 6-linked Glcp, terminal and 1, 5-linked Araf, terminal, 1, 4-linked, 1, 6-linked and 1, 4, 6-linked Galp, terminal, and, 1, 4-linked and 1, 4, 6-linked Manp. The bioassay experiments revealed that BC-PS2 inhibited complement activation on both the classical and alternative pathways, with CH50 and AP50 of (0.222 ± 0.013) and (0.356 ± 0.032) mg·mL(-1), respectively. Preliminary mechanism studies indicated that BC-PS2 interacted with C1q, C2, and C9 components.@*CONCLUSION@#The results demonstrated that BC-PS2 is an anti-complementary polysaccharide, and should be important constituent of the root of Bupleurum chinense for its application in the treatment of diseases associated with the excessive activation of complement system.

Study on quality specification of Rhizoma et Radix Valeriana Jatamansi / 中国中药杂志

<p><b>OBJECTIVE</b>To provide scientific basis for the utilization and development of Valeriana jatamansi by setting up the quality control specification of V. jatamansi.</p><p><b>METHOD</b>The pharmacognostical methods were applied. The extract of V. jatamansi was examined. Moisture and ash were determined. And the bioactive constituents were analyzed by TLC and HPLC.</p><p><b>RESULT</b>The morphological and histological characters of V. jatamansi were observed. Content of total ash, acid-insoluble ash, and moisture of 15 samples from different habitats and times were determined. The qualitative and quantitative analysis of valtrate and acevaltrate by TLC and HPLC were preformed respectively.</p><p><b>CONCLUSION</b>The established method can be used for the quality control of V. jatamans.</p>