Objective: To study the antiviral effect of polysaccharides from brown seaweed Lobophora variegata. Method: The crude polysaccharide was extracted with boiling water and precipitated with ethanol,and then fractionated with ion exchange chromatography. Its antiviral activity was tested by cytopathic effect (CPE) reduction assay and plaque reduction assay. The cytotoxicity of the water crude extract was determined by MTT method. Results: The crude water extract showed markedly antiviral activity against herpes simplex virus (HSV) type 1 and type 2 including ACV resistant strain and clinical strains with low EC50 values of 18.2 and 6.25 μg/ml respectively. It also showed very low cytotoxicity to Vero, HEp-2 and MDCK cells. Therefore, the crude extract possessed high selective index for antiviral effect. It also had some inhibitory effect on respiratory syncytial virus (RSV) but had no effect on influenza A virus. Two fractions were isolated from the water crude extract and they exhibited anti-HSV activity in the test of CPE reduction assay in Vero cells. Conclusion: Seaweed Lobophora variegata contains antiviral polysaccharides with high inhibitory effect on herpes simplex virus.

Objective: Soy products may cause excessive intestinal gas because of soybean oligosaccharides . The effect of recombinant ?-galactosidase on eliminating mouse flatus was observed. Methods:The mouse model of flatulence was set up by ig raffinose and stachyose and the flatulence was investigated by measuring intestinal flatulent volume. Oligosaccharides were examined by TLC test and soybean protein was examined by SDS-PAGE. Results: Raffinose and stachyose can result in mouse flatus and recombinant ?-galactosidase can eliminate it without any effect on soybean protein. Conclusion: Recombinant ?-galactosidase can eliminate flatus, and be used as food additive.

Objective: To investigate the effect of oat?-glucan on colon flora and its function in mice. Method:126 Kunming mice(23-25g)were divided into seven groups (18 mice in each). The group 1 and 2, 3 and 4 ,5 and 6 were respectively administered oat?-glucan (OG2600 , OG340 and OG5) at dose of 0.25 and 0.5g/(kg bw?d)daily for 28 d. The control group received the equal volume of normal saline. Bifidobacterium , Lactobacillus and Enterobacillus were monitored in colon after oral administration of oat ?-glucan at 14 d, 28 d and 35 d (after terminating oat?-glucan admimistration for 1 w) . The contents of short chain fatty acids (SCFA) in colon were analyzed by GC and cell proliferation in colonic mucosa epithelium by FCM in each group. ResuIts:The numbers of Bifidobacterium , Lactobacillus compared with the control were significantly increased and Enterobacillus strains were decreased in experimental groups. Oat ?-glucan had the function of regulating intestinal flora and the effect was related to molecular weight and dosage. The contents of acetate, propionate, butyrate were higher in the group 2, 4 and 6 compared with the control (P

Objective: To explore the effect of iodine overdose on cathepsin B and D in thyroidcell line (FRTL). Method: The cells were treated with potassium iodide (0, 1, 5, 10, 50 and 100mmol/L). After treatment 6, 12, 24, 48 and 72 hours, the cells were collected. The activities of cathepsin B (CB) and cathepsin D (CD) were assayed by fluorospectrophotometry and Lowry, respectively. The mRNA levels of CB and CD were determined with real-time PCR. Results: After 12 and 24 hours, the activities of CB and CD, treated by 50mmol/L potassium iodide were decreased significanty. The mRNA levels of CB and CD of 50mmol/L potassium iodide group were decreased significanty after treatment 24 hours. Conclusion: The decreased activities of CB and CD were one of reasons of thyroid colloid retention resulted from iodine excess.

Objective: To investigate the effects of selenium-enriched probiotics on immunity and antioxidation function in mice. Method: One hundred healthy KM mice, female and male in half, were randomly divided into control, sodium selenite, selenium-enriched yeast (Se yeast), selenium-enriched probiotics (Se probiotics) and probiotics groups. One milliliter of water, sodium selenite (2 ?g Se/ml), Se yeast (2 ?g Se/ml), Se probiotics (2 ?g Se/ml) or probiotics were respectively supplemented to five groups in oral (ig) every day. Whole experiment lasted for 28 d. During the experiment, immunity and antioxidation functions were measured respectively. Results: The activation of peritoneal macrophage and thymus index in Se probiotics group were significantly higher than those of other four groups. The spleen index of Se probiotics group was higher than that of control, sodium selenite and probiotics group. The spleen lymphocyte transformation rate in Se probiotics group was significantly or very significantly higher than that in control or probiotics group. In addition, blood GSH-Px and plasma SOD activity in Se probiotics group were significantly higher than those in control and sodium selenite group. Plasma MDA concentration in Se probiotics group was very significantly lower than that in control and sodium selenite group. Conclusion: Selenium-enriched probiotics supplementation could significantly enhance immunity and antioxidation function in mice.