Objective To detect the antiviral effect and its antiviral mechanism of the sulfated polysaccharide SP2 isolated from the brown alga Sargassum patens C. Ag. against RSV.Methods The antiviral activity,cytotoxicity and its possible antiviral mechanism were assayed by cytopathogenic effect (CPE) inhibition assay,MTT assay and plaque reduction assay. Reduction assay when it was added during virus adsorption. It did not show any antiviral activity against influenza A and B viruses and parainfluenza type 3 virus up to the concentration of treatment of cells with SP2 did not protect the cells from RSV infection. This polysaccharide addition assay showed that when SP2 was present only during virus adsorption phase at 37℃, it could significantly inhibit RSV-induced plaque formation. Conclusions SP2 might be a potent substance for treating RSV infection. The mode of action of SP2 might depend on inhibiting RSV attachment to host cells.

Objective To investigate the inhibitory effect of DHA and its mechanism of apoptosis induced by DHA on human gastric cancer cell SGC-7901.Methods The survival rate of tumor cells was evaluated by MTT assay,cell morphology of apoptotic cell was observed with Hoechest 33258 staining.The contents of MDA and GSH were measured respectively by TBA and DTNB assay.Flow cytometry was used to detect the rate of apoptotic cell and intracellular variation of ROS level.Results After being treated with different concentrations of DHA,the survival rate of tumor cells was decreased in a dose-dependent manner and apoptosis was induced.The morphological characterizes of apoptotic cells were chromatin condensation and formation of apoptotic bodies.Intracellular MDA content was increased in the treated cells compared with control group,whereas GSH was decreased.After treated with 80 ?mol?L-1 DHA 5 h,flow cytometic analysis showed ROS peak and NAC could block the generation of ROS.Conclusion DHA can inhibit the growth of human gastric cancer cell SGC-7901 via inducing apoptosis.The increase of lipid peroxidation production and ROS may play an important role in apoptosis of the cells.

Objective To observe the effects of Chlamys farreri skirt glycosaminoglycan(SS-GAG) on the expressions of c-myc and TNF-? genes so as to explore the anti-atherosclerosis(AS) mechanism of SS-GAG.Methods The cell proliferation model of vascular smooth muscle cells(VSMC) was established by basic fibroblast growth factor(bFGF) induction.In Situ hybridization marked by non-isotope was applied to determine the effects of SS-GAG on the mRNA levels of c-myc and TNF in proliferative VSMC.Results The mRNA levels of c-myc and TNF in low dose group and high group of SS-GAG were obviously lower than that of model group(P

Objective To screen for ?-glucosidase inhibitors from the extracts of marine invertebrates collected at the seashore of Qingdao China.Method The 95% ethanol extracts of 33 species of marine invertebrates were screened for the presence of ?-glucosidase inhibitors using rapid colorimetric method.Result Some extracts have inhibitory activity against ?-glucosidase,among which the extracts of Tubularia marina,Asterina pectinifera,Apostichopus japonicus and Scapharca subcrenata have much higher inhibitory rate: 56.1%,67.3%,62.2%,and 66.3% at the concentration of 0.6 mg?mL-1.Conclusion The results suggested that marine invertebrates are sources of new ?-glucosidase inhibitors.

Objective To investigate the antimicrobial and antitumor activities of extracts from the root of mangrove plant,Kandelia candel.Methods Micro-dilution and MTT method were used to test the antimicrobial and antitumor activities of extracts from the root of K.candel.Results The petroleum ether extracts of root could inhibit the growth of Staphylococcus aureus,S.epidermidis,Bacillus subtilis and Sarcina lutea with the minimal inhibitory concentration(MIC) of 3.125 mg?mL-1,1.5625 mg?mL-1,0.78125 mg?mL-1 and 3.125 mg?mL-1 respectively.The ethyl acetate extracts and ethyl alcohol extracts could inhibit the growth of S.epidermidis with MIC of 3.13 mg?mL-1 and 6.25 mg?mL-1 respectively.At the same time,the petroleum ether extracts could inhibit the proliferation of tumor cells,such as SMMC-7721,B16,BGC803 and HepG2 with IC50 of 355.2?g?mL-1,378.6?g?mL-1,275.6?g?mL-1 and 411.6?g?mL-1 respectively,while the other extracts could stimulate the proliferation of tumor cells apparently.Conclusion The antimicrobial and antitumor activities of extracts from the root of K.candel indicate the potential pharmaceutical usage of this plant.

Objective To prepare insulin-containing chitosan-thioglycollic acid conjugates microspheres and evaluate their hypoglycemic effect.Methods The insulin-containing chitosan-thioglycollic acid conjugates microspheres were prepared by the dry-in-oil method using the chitosan-thioglycollic acid conjugates which the content of thiol group was 983?mol?g-1.The hypoglycemic effect of the microsphere was evaluated by drug release test in vitro and hypoglycemic test on hyperglycemic rats.Results The insulin-containing chitosan-thioglycollic acid conjugates microspheres with an average diameter of 13?m were administered by intraduodenal and intraileal application,and gave visible decrease in plasma glucose level in 4h at a dose of 20IU?kg-1.The relative bioavailability of the latter compared to hypodermic injection was 29.9%.Couclusion The results showed that the bioavailability of oral insulin could be facilitated by insulin-containing chitosan-thioglycollic acid conjugates microspheres,and good biological availability was obtained when the microspheres were administered by intraileal application.

Objective To extract dietary fiber from Udaria pinnatifida by using enzymatic-chemical extraction method.Methods All the factors that affect the extraction rate are enzyme content,enzymolysis temperature,enzymolysis time,Na2CO3concentration,Na2CO3extraction temperature,Na2CO3content and extraction time.They were tested with orthogonal experiment.Results The optimal conditions for extraction were determined as follows:the material was hydrolyzed at 50℃ for 1.5h with protease and cellulase mixed at the ratio of 30∶1,followed by the extraction at 65℃ for 3h with 30 volumes of 1% Na2CO3 solution.Under these conditions,the extraction rate could be as high as 12.65%with the color near light yellow.It could be used as additive source of dietary fiber for functional foods.Conclusion The optimum conditions for extraction dietary fiber were established.

Objective To investigate the effects of polysaccharide from Porphyra on spleen cell function in immunosuppressive mice. Methods The polysaccharide at dosages 0.025, 0.050 and 0.150g?kg~ -1 was injected intraperitoneally for 7 days in the immunosuppressive mice induced by cyclophosphamide. On day 8, the splenic lymphocytic proliferation and activity of TNF were determined. Results The splenic lymphocytic proliferation and cytotoxicity of tumor necrosis factor (TNF) of the group treated with 0.150g?kg~ -1 of porphyra polysaccharide were higher than those of model group. Conclusion Polysaccharide from Porphyra could promote splenic lymphocytic proliferation and raise the level of TNF.

Objective To study the antitumor mechanism of DHA compound. Methods RT-PCR was used to investigate the effects of DHA compound on H-Ras and pl6 mRNA transcription in gastric adenocarcinoma. Results Compared with control, the content of H-Ras mRNA was decreased and the content of p16 mRNA was increased in gastric adenocarcinoma significantly after treated with DHA compound. Conclusion The transcription of H-Ras gene was decreased and the transcription of pl6 gene was increased in gastric adenocarcinoma after treated with DHA compound and thus the cancer cell growth was inhibited.

Objective The polysaccharides sulfate were extracted from three kinds of algae in-cluding porphyra tenera , Laminaria ja ponica and Sargassum fusi forme ( Harv. )Setch . in order to screen antioxidant with exploiting potential. Methods Using the assay system of DP-PH,the antioxidative activities of various extracts were studied. Results Three kinds of algae polysaccharides sulfate had different antioxidative activities. Moreover, polysaccharide extracted with different solvents had different intensities of antioxidative activity. Conclusion Polysacchride sulfate extracted with water has stronger antioxidative activity than that with others.keywolds antioxidation; porphyra tenera kjellm. ; Laminaria japonica; Sargassum fusi -forme ( Harv. )Setch.Studies on the extraction of polysaccharides sulfate from three algae and their scavenging activity on free radicalsHAN Hua,ZHOU Hai Yan,LIU Cheng-Chu,WANG Chun-bo(1.Bromatology Institute of Shanhai Aquatic University , Shanghai 200090, China; 2. Medical College , Qingdao University ,Qingdao 266021, China)Abstract:Objective The polysaccharides sulfate were extracted from three kinds of algae in-cluding porphyra tenera , Laminaria ja ponica and Sargassum fusi forme ( Harv. )Setch . in order to screen antioxidant with exploiting potential. Methods Using the assay system of DP-PH,the antioxidative activities of various extracts were studied. Results Three kinds of algae polysaccharides sulfate had different antioxidative activities. Moreover, polysaccharide extracted with different solvents had different intensities of antioxidative activity. Conclusion Polysacchride sulfate extracted with water has stronger antioxidative activity than that with others.