Research on the optimization, key chemical constituents and antibacterial activity of the essential oil extraction process of Thuja koraiensis Nakai.

Thuja koraiensis Nakai is a kind of precious economic tree species with fragrance, ornamental and medicinal functions. The essential oil has the satisfactory antibacterial activity. In this paper, the essential oil from the branches and leaves of Thuja koraiensis Nakai was studied by optimization of extraction process, and the optimized parameters mainly include solid-liquid ratio, NaCl concentration, distillation time, storage conditions, etc. Which provided technical scientific basis for the development and utilization of Thuja koraiensis Nakai. The essential oil from the branches and leaves of Thuja koraiensis Nakai was extracted by steam distillation, and the single factor experiment was carried out. The extraction process of the essential oil from the branches and leaves of Thuja koraiensis Nakai was optimized by response surface methodology. The chemical constituents were analyzed by GC-MS. The antibacterial activity of the essential oil was detected by filter paper and plate coating methods. Thuja koraiensis Nakai showed that when the material-to-liquid ratio was 50 g/400 ml, the NaCl concentration was 6.0%, the distillation time was 5 h,the storage condition was dry branch, the oil content was the highest. The response surface optimization method showed that material-to-liquid ratio was 7.8804 ml/g, distillation time was 2.23 h, NaCl concentration was 6.56%, under such condition, the yield was 1.1712%. The chemical constituents of the essential oil were analyzed by GC-MS (gas chromatography-mass spectrometry), and 45 compounds were detected, accounting for 96.03% of the total number. The bacteriostatic activity was detected by filter paper method. The results showed that the essential oil of Thuja koraiensis Nakai had antibacterial effect on three strains (Staphylococcus aureus, Bacillus subtilis and Escherichia coli), among them, the diameter of bacteriostatic circle against S. aureus, B. subtilis and E. coli was 10.00 mm, 15.20 mm and 9.86 mm. The minimum inhibitory concentration (MIC) of the branches and leaves of Thuja koraiensis Nakai to S. aureus was 5 µg/ml, to B. subtilis was 0.625 µg/ml and to E. coli was 2.50 µg/ml. The highest extraction yield of essential oil from the branches and leaves of Thuja koraiensis Nakai by steam distillation was 1.30%. A total of 45 compounds were identified from the essential oils of Thuja koraiensis Nakai, among which carverol acetate was the highest. The essential oil from the branches and leaves of Thuja koraiensis Nakai has obvious antibacterial effect and great development potential, for example, making insect repell0ents, fungicides, essential oil soaps, so it is recommended to collect and use it.

Anti-tumor and immunomodulatory activities induced by an alkali-extracted polysaccharide BCAP-1 from Bupleurum chinense via NF-κB signaling pathway.

Bupleurum chinense is a well-known traditional Chinese medicine. Polysaccharides extracted from medical plants possess multiple healthy benefits. In the present study, an alkali-extracted polysaccharide (BCAP-1) was isolated from Bupleurum chinense, and evaluated its physicochemical features, anti-tumor activities and immunomodulatory effects. BCAP-1 was obtained by alkali-extraction, ethanol precipitation, and fractionation by DEAE-cellulose and Sepharose CL-6B columns. BCAP-1 markedly inhibited Sarcoma 180tumor growth in tumor-bearing mice, and increased the secretion of TNF-α in serum. MTT assay showed that BCAP-1 had no cytotoxicity against S-180 tumor cells. BCAP-1 enhanced the secretion of TNF-α and NO, and the transcripts of TNF-α and iNOS were increased. Meanwhile, BCAP-1 treatment induced the phosphorylation of p65 and decreased the expression of IκB in macrophages. These results suggest that BCAP-1 could activate macrophages through NF-κB signaling pathway, and the anti-tumor effects of BCAP-1 can be achieved by its immunostimulating features.

Two new proanthocyanidins from the leaves of Garcinia multiflora.

Two new proanthocyanidins, namely garcinianin A (1) and garcinianin B (2), together with two known compounds (3 and 4) were isolated from the leaves of Garcinia multiflora Champ. Their structures were elucidated on the basis of spectroscopic analysis.

Structural characterization and in vitro inhibitory activities in P-selectin-mediated leukocyte adhesion of polysaccharide fractions isolated from the roots of Physalis alkekengi.

Selectin-mediated leukocyte initial attachment and rolling over vessel endothelial surface are crucial steps for inflammatory responses. As P-selectin is a promising target for anti-inflammation therapeutic strategy, recent works have focused on searching for more potent and non-toxic P-selectin antagonists among various natural carbohydrate products. Here, we isolated three water-soluble polysaccharide fractions (PPS-1, PPS-2 and PPS-3) from the roots of Physalis alkekengi by DEAE-cellulose and Sephacryl S-200 chromatography. Their physicochemical and structural characterizations were determined by chemical methods, GC (gas chromatography), HPLC (high performance liquid chromatography), FT-IR (Fourier transform infrared spectrometry), partial acid hydrolysis, methylation and GC-MS (gas chromatography-mass spectrometry) analyses. The inhibitory capacity of the polysaccharide fractions in P-selectin-mediated leukocyte adhesion was evaluated by flow cytometric, static adhesion and laminar flow assays. Results showed that different polysaccharide fractions possess distinct physicochemical and structural properties, including carbohydrate, protein and uronic acid contents, molecular weight, monosaccharide composition and glycosidic linkage type. Among the polysaccharide fractions, PPS-2 could effectively block the interaction between P-selectin and its native ligand.