[Structural characterization of PCP-â from Poria as vaccine adjuvant and its hydrolytic oligosaccharide].

Poria is an important medical herb in clinic. The authors isolated a polysaccharide(PCP-Ⅰ) from Poria in previous studies, which is composed of galactose, mannose, fucose and glucose. PCP-Ⅰ exhibited significant adjuvant effects on H1N1 influenza vaccine, hepatitis B surface antigen and anthrax protective antigen, and its adjuvant activity was stronger than aluminium adjuvant. However, little is known about the chemical structure of PCP-Ⅰ at present. In this study, weak acid hydrolysis was used to obtain the backbone oligosaccharide of PCP-Ⅰ. Then periodate oxidation, Smith degradation, methylation analysis, Fourier transform infrared spectroscopy(FT-IR), nuclear magnetic resonance(NMR) and gas chromatography-mass spectrometry(GC-MS) were performed to investigate the chemical structural features of PCP-Ⅰ and its hydrolytic oligosaccharide(PCP-Ⅰ-hy-1). These results suggested that the backbone of PCP-Ⅰ was composed of galactose with α anomeric carbon and ß anomeric carbon. The linking residues of galactan are(1→),(l→6) and(1→2,6).

Chemical characters and protective effect of Baqi Lingmao formula on experimental liver injury.

OBJECTIVE: To investigate the chemical characters of water-extract of Baqi Lingmao formula (BQLM formula) and its effects on anti-liver injury in model mice and live cells. METHODS: BQLM formula was composed of ten herbal medicines. We determined the contents of alkaloids, saponins, phenolic acids and flavonoid in BQLM formula by UV spectrophotometry. The active components of alkaloids and phenolic acids in BQLM formula were identified by HPLC chromatography. The anti-hepatic injury effects of BQLM formula were investigated with concanavalin A (ConA)-induced hepatitis model of mice, human liver LO2 and HepG2.2.15 cells. RESULTS: BQLM formula (2 and 10 g/kg, orally) significantly improved the damages of liver tissues and functions caused by ConA in mice, reduced the infiltration of inflammatory cells into liver and inhibited the inflammatory cytokine secretion of interferon-γ, tumor necrosis factor-α and interleukin-6. BQLM formula simultaneously decreased the levels of alanine aminotransferase and aspartate aminotransferase of liver and serum, and recovered the superoxide dismutase and catalase activities of liver to normal levels in ConA-induced hepatic-injury mice. The serum of BQLM formula group stimulated the human liver LO2 cell proliferation in vitro. Further, BQLM formula obviously promoted the proliferation of normal hepatocytes (LO2 cells) and inhibited the hepatocytes death induced by ConA. It also significantly inhibited the proliferation of HepG2.2.15 cells and decreased the secretion of HBsAg and HBeAg in vitro. CONCLUSIONS: BQLM formula has anti-inflammation and anti-hepatitis virus Beffects, and is capable of improving liver injury in vivo and in vitro.

Longibramides A-E, Peptaibols Isolated from a Mushroom Derived Fungus Trichoderma longibrachiatum Rifai DMG-3-1-1.

Five new peptaibols, longibramides A-E (1-5) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A-E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A-E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C-E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future.

The potential adjuvanticity of quaternized chitosan hydrogel based microparticles for porcine reproductive and respiratory syndrome virus inactivated vaccine.

Infectious diseases possess a big threat to the livestock industry worldwide. Currently, inactivated veterinary vaccines have attracted much attention to prevent infection due to their safer profile compared to live attenuated vaccine. However, its intrinsic poor immunogenicity demands the incorporation of an adjuvant. Mineral oil based adjuvant (Montanide™ ISA206) was usually used to potentiate the efficacy of veterinary vaccines. However, ISA206 could not induce robust cellular immune responses, which was very important in controlling virus replication and clearing the infected cells. Moreover, mineral oil would result in severe side effects. To improve both the humoral and cellular immune responses of porcine reproductive and respiratory syndrome virus (PRRSV) inactivated vaccine, we developed pH-sensitive and size-controllable quaternized chitosan hydrogel microparticles (Gel MPs) without using chemical cross linking agent. Gel MPs, ionic cross-linked with glycerophosphate (GP), were biocompatible and could efficiently adsorb the inactivated PRRSV vaccine with a loading capacity of 579.05µg/mg. After intramuscular immunization in mice, results suggested that Gel MPs elicited significantly higher cell-mediated immune responses and comparable humoral immune responses compared to ISA 206. Regarding the biocompatibility, safety and effectiveness, Gel MPs would be a promising candidate to enhance the efficacy of veterinary vaccine.

A polysaccharide from the stems of Rubus amabilis Focke and its immunological enhancement activity.

A water-soluble polysaccharide (named RAP) was newly isolated from the stems of Rubus amabilis. Structural confirmation of the polysaccharide was provided by hydrolysis, periodate oxidation, Smith degradation, and methylation analysis, combined with nuclear magnetic resonance (NMR), capillary electrophoresis (CE), infrared spectroscopy (IR), and gas chromatography-mass spectra (GC-MS). In vitro immunological enhancement activity was characterized using the proliferative activity of spleen lymphocytes and phagocytic activity of peritoneal macrophages in mice. The polysaccharide was mainly composed of xylose, arabinose, glucose, rhamnose, galactose, mannose, glucuronic acid, and galactocuronic acid in the molar ratio of 1.0:6.9:0.8:1.1:6.9:0.3:0.5:3.3, with the average molecular weight of 26.2 kDa. The linkage types of netural monosaccharides were as follows: the arabinose was →2) Ara (1→ and galactose were Gal (1→, →3) Gal (1→, →3,6) Gal (1→, →2,3,6) Gal (1→ and →2,3,6) Galf (1→. Xyl (1→, →6) Glc (1→, →2) Glc (1→, →3) Rha (1→, Rha (1→ and Man (1→ were also found in the structure. RAP-B-2 could improve the proliferative activity of spleen T cells and B cells and boost phagocytic activity of peritoneal macrophages at the concentration of 50 µg/ml (p < 0.05, p < 0.01).

Identification of a methyltransferase encoded by gene stel16 and its function in Ebosin biosynthesis of Streptomyces sp. 139.

Streptomyces sp. 139 generates a novel exopolysaccharide (EPS) designated as Ebosin, which exerts an antagonistic effect on IL-1R in vitro and anti-rheumatic arthritis activity in vivo. A ste gene cluster for Ebosin biosynthesis consisting of 27 ORFs was previously identified in our laboratory. In this paper, ste16 was expressed in Escherichia coli BL21 and the recombinant protein was purified, which has the ability to catalyze the transfer of the methyl group from S-adenosylmethionine (AdoMet) to dTDP-4-keto-6-deoxy-D-glucos, which was thus identified as a methyltransferase. In order to determine the function of ste16 in Ebosin biosynthesis, the gene was disrupted with a double crossover via homologous recombination. The monosaccharide composition of EPS-m generated by the mutant strain Streptomyces sp. 139 (ste16) was found to differ from that of Ebosin. The IL-1R antagonist activity of EPS-m was markedly lower than that of Ebosin. These experimental results have shown that the ste16 gene codes for a methyltransferase which is involved in Ebosin biosynthesis.

Identification of alpha-D-glucose-1-phosphate cytidylyltransferase involved in Ebosin biosynthesis of Streptomyces sp. 139.

Ebosin, a novel exopolysaccharide produced by Streptomyces sp. 139 has antagonist activity for IL-1R in vitro and remarkable anti-rheumatic arthritis activity in vivo. Its biosynthesis gene cluster (ste) has been identified. In this study, gene ste17 was expressed in Escherichia coli BL21 and the recombinant protein was purified. With CTP and alpha-D-glucose-1-phosphate as substrates, the recombinant Ste17 protein was found capable of catalyzing the production of CDP-D-glucose and pyrophosphate, demonstrating its identity as an alpha-D-glucose-1-phosphate-cytidylyltransferase (CDP-D-glucose synthase). To investigate the function of ste17 in Ebosin biosynthesis, the gene was disrupted with a double crossover via homologous recombination. The monosaccharide composition of exopolysaccharide (EPS) produced by the mutant Streptomyces sp. 139 (ste17 (-)) was found significantly altered from that of Ebosin, with glucose becoming undetectable. This gene knockout also negatively affected the antagonist activity for IL-1R of EPS. These results indicate that the CDP-D: -glucose synthase encoded by ste17 gene is involved in the formation of nucleotide sugar (CDP-D-glucose) as glucose precursor in Ebosin biosynthesis.

Knockout of the gene (ste15) encoding a glycosyltransferase and its function in biosynthesis of exopolysaccharide in Streptomyces sp. 139.

Streptomyces sp. 139 produces a novel exopolysaccharide (EPS) designated Ebosin which has antagonistic activity for IL-1R in vitro and remarkable anti-rheumatic arthritis activity in vivo. We previously identified a ste (Streptomyces eps) gene cluster consisting of 27 ORFs responsible for Ebosin biosynthesis. The gene product of ste15 shows high homology to known glycosyltransferases (GTFs). To elucidate its function in Ebosin biosynthesis, the ste15 gene was knocked out with a double crossover via homologous recombination. Our analysis of monosaccharide composition for EPS-m produced by the mutant strain Streptomyces sp. 139 (ste15(-)) showed that glucose was significantly diminished compared to its natural counterpart Ebosin. This derivative of Ebosin lost the antagonistic activity for IL-1R in vitro and its molecular mass was smaller than Ebosin. These results have demonstrated that the ste15 gene codes for a GTF for glucose, which is functionally involved in Ebosin biosynthesis.

Anti-diabetic and hypolipidemic effects of aqueous-extract from the flower of Inula japonica in alloxan-induced diabetic mice.

The anti-diabetic and hypolipidemic effects of aqueous-extract from the flower of Inula japonica (IJ) and its two fractions (IJR and IJP) were investigated in alloxan-induced diabetic mice. An oral glucose tolerance test (OGTT) of IJ was also performed in normal and diabetic mice. The results showed that IJ (1000 mg/kg), IJR (500 mg/kg) and IJP (250 mg/kg) significantly reduced blood glucose levels in diabetic mice by oral administration (p<0.01). IJ and IJP markedly decreased serum triglyceride concentrations (p<0.05) in diabetic mice. Their hypoglycemic activities were better than gliclazide (40 mg/kg) and compared with metformin (250 mg/kg). IJ raised plasma insulin levels in alloxan-induced diabetic mice. IJ, IJR and IJP significantly decreased the consumption of water and food in diabetic mice. OGTT showed that IJ slightly lowered blood glucose levels in normal mice, but significantly decreased blood glucose in diabetic mice between 60-150 min after a glucose load (p<0.05). The data indicated that IJ has both anti-diabetic and hypolipidemic effects.

[Studies on physico-chemical properties and hypoglycemic activity of complex polysaccharide AMP-B from Atractylodes macrocephala Koidz].

AIM: To isolate a complex polysaccharide (AMP-B) from Atractylodes macrocephala Koidz and study its phtsico-chemical properties and hypoglycemic activity. METHODS: The root of Atractylodes macrocephala K. was extracted with water and precipitated with ethanol, dialyzed against water and freeze-dried to get the crude polysaccharides (AMP). A complex polysaccharide (AMP-B) was isolated and purified on DEAE-cellulose column. The model of diabetes rats was established with alloxan injection through the tail vein. Male rats were divided into 5 groups: the normal group, the control group, and three AMP-B-fed groups. Measuring the blood glucose, water and food consumption, thymus and pancreas index, and studying cut sections of pancreas tissues. RESULTS: AMP-B is a complex-polysaccharide, elemental analysis of AMP-B shown C 32.84%, H 5.68%, and N 1.79%. The neutral polysaccharide content of AMP-B was 50.3%, uronic acid was 40.4%, and protein was 11.5%. Monosaccharide composition of AMP-B was determined by GC, AMP-B composed of Glc, Gal, Man, Ara and Rha in a molar ratio of 3.0:2.5:1.3:3.5:1.0. AMP-B was found to reduce blood glucose level in alloxan-diabetic rats markedly at doses of 50, 100 and 200 mg.kg-1 by ig, but no effect in normal rat. AMP-B was found to decrease the consumption of water and food, recover pancreas damage of diabetic rats obviously, inhibited the atrophy of thymus and pancreas of the diabetic rats induced by alloxan. CONCLUSION: AMP-B showed significant hypoglycemic effect on the experimental hyperglycemias rats induced by alloxan.

[Effect of Angelica sinensis polysaccharides on lymphocyte proliferation and induction of IFN-gamma].

AIM: To study the effect of Angelica sinsensis polysaccharides on lymphocyte proliferation and induction of IFN-gamma. METHODS: Angelica sinensis polysaccharides(AP) were separated into AP-I, AP-II, AP-III and AP-IV by alcohol deposition with different concentration. The radioactivities of [3H]-TdR uptake by lymphocyte were used to determine the ability of lymphocyte. The bioactivity of IFN-gamma was measured by violet crystalline dying. RESULTS: AP-IV was found to be composed of Ara and Glu in the ratio of 0.99:6.47, the molecular weight was estimated to be 5,600. AP-I and AP-II 100 mg.kg-1 i.p. were found to significantly augment mice splenocyte proliferation, release IFN-gamma and increase IFN-gamma bioactivity. 50 micrograms.mL-1 AP-I, AP-II and AP-III were shown to enhance the proliferative response of the mouse spleen lymphocytes in vitro. CONCLUSION: AP-I and AP-II showed higher immunoactivity than AP-III, AP-IV had no effect.