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The aim of this study was to probe the potential anti-H. pylori activity of the synthetic antimicrobial peptide pexiganan, which is an analog of the peptide magainin, and its nanoparticles (PNPs) that were prepared in our laboratory. To compare their antibacterial effects in vitro and in vivo, studies of H. pylori growth inhibition, kinetics and resistance assays were undertaken. The gastric mucoadhesive efficiency and H. pylori clearance efficiency of pexiganan and PNPs were evaluated in rats and mice infected with H. pylori. The eradication of H. pylori was determined using urease tests and a microbial culture method. We observed that PNPs adhered to gastric mucosa more effectively owing to a prolonged stay in the stomach, which resulted in a more effective H. pylori clearance. In addition, PNPs had greater anti-H. pylori effect than pexiganan in infected mice. The amount of pexiganan required to eradicate H. pylori was significantly less using PNPs than the corresponding pexiganan suspension. The results confirmed that PNPs improved peptide stability in the stomach and more effectively eradicated H. pylori from mice stomachs than pexiganan.

A novel gene of thermostable phytase, phyA, was isolated by polymerase chain reaction (PCR) techniques from Aspergillus aculeatus RCEF 4894. The full-length phyA gene comprises 1,404 bp and encodes 467 amino-acid residues, including a 19-residue putative N-terminal signal peptide. The phytase of A. aculeatus was a novel addition to the histidine-acid phosphatase family, as evidenced by both the conserved motifs RHGXRXP and HD in the amino-acid sequence, and 3D structure models. The recombinant phytase was overexpressed in Pichia pastoris, and its specific activity reached 3,000 U mL−1 at the optimum pH of 5.5. This recombinant, thermostable phytase was able to withstand temperatures of up to 90 °C for 10 min, with a loss of only 13.9% of initial enzymatic activity, and showed high activity with phytic-acid sodium salt at a pH range of 2.5–6.5. The broad pH optima and high thermostability of the phytase makes it a promising candidate for feed-pelleting applications.

Helicobacter pylori (H. pylori)-induced oxidative stress has been shown to play a very important role in the inflammation of the gastric mucosa and increases the risk of developing gastric cancer. Resveratrol has many biological functions and activities, including antioxidant and anti-inflammatory effect. The purpose of this study was to probe whether resveratrol inhibits H. pylori-induced gastric inflammation and to elucidate the underlying mechanisms of any effect in mice. A mouse model of H. pylori infection was established via oral inoculation with H. pylori. After one week, mice were administered resveratrol (100 mg/kg body weight/day) orally for six weeks. The mRNA and protein levels of iNOS and IL-8 were assessed using RT-PCR, Western blot and ELISA. The expression levels of IκBα and phosphorylated IκBα (which embodies the level and activation of NF-κB), Heme Oxygenase-1 (HO-1, a potent antioxidant enzyme) and nuclear factor-erythroid 2 related factor 2 (Nrf2) were determined using Western blot, and lipid peroxide (LPO) level and myeloperoxidase (MPO) activity were examined using an MPO colorimetric activity assay, thiobarbituric acid reaction, and histological-grade using HE staining of the gastric mucosa. The results showed that resveratrol improved the histological infiltration score and decreased LPO level and MPO activity in the gastric mucosa. Resveratrol down-regulated the H. pylori-induced mRNA transcription and protein expression levels of IL-8 and iNOS, suppressed H. pylori-induced phosphorylation of IκBα, and increased the levels of HO-1 and Nrf2. In conclusion, resveratrol treatment exerted significant effects against oxidative stress and inflammation in H. pylori-infected mucosa through the suppression of IL-8, iNOS, and NF-κB, and moreover through the activation of the Nrf2/HO-1 pathway.

To study the extraction conditions of mycelium polysaccharides from selenium-rich Morchella esculenta with neutral proteinase for increasing of yield.On the basis of single factor tests, orthogonal experiment design was applied to analyze the influence of factors including enzyme dosage, enzymolysis time, enzymolysis temperature and material/liquid ratio on the extraction rate of the polysaccharides.The optimal extraction conditions of mycelium polysaccharides from selenium-rich Morchella esculenta was as follows: enzyme dosage was 1.5%, enzymolysis time was 2 h, enzymolysis temperature was 40 degrees C, and material/liquid ratio was 1:15. The extraction rate of polysaccharide was 11.26% under the extraction conditions.The process is simple, stable and practicable, and can be used for the extraction of mycelium polysaccharides from selenium-rich Morchella esculenta.

Ultrasonic technology was applied to extract mycelial polysaccharides fromPaecilomyces hepiali and the process was optimized by response surface methodology. Antioxidant activity of polysaccharides was also investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (%DPPHsc). Three independent variables were ratio of water to raw material (x1), ultrasonic power (x2) and extraction time (x3). Statistical analysis indicated that x1, x2, x12, x32, x1x2, x1x3and x2x3 had significant effect on the yields. Besides, x2, x12 and x22 shaped the %DPPHsc of polysaccharides significantly. Three dimensional surface plots and contour plots were drawn from the mathematical model. The optimal conditions for yield and %DPPHsc were as follows: condition (1) x1 = 125 mL/g, x2 = 300 W, x3 = 12 min, and condition (2) x1 = 125 mL/g and x2 = 500 W, x3 = 11 min, respectively. Under these conditions, the yield was 9.37%, and %DPPHsc was 45.34%. There existed good agreement between experimental and predicted values. Key words: Ultrasonic extraction, polysaccharides, Paecilomyces hepiali, response surface methodology, antioxidant activity.

A F2 population containing 180 lines, which was derived from the cross between the partially sequenced indica variety "Pei'ai 64S" and the completely sequenced japonica variety "Nipponbare" , was used to construct a genetic linkage framework map (referred to as F2 map), which included 138 microsatellite sites and covered 1737.81 cM of total genomic length, an average distance of 11.90 cM. Single seed descent F2:6 population with 330 lines was used to construct a genetic linkage map (known as F6 map) using 92 markers. The total genomic length and average distance were 2563.5 cM and 27.86 cM, respectively. The F2 and F6 maps differed in linkage groups, mapped markers, sequenced order of markers, ge-netic distance and average distance on the maps. Preliminary analysis about these difference was carried out.