Lin Song is now a second-year PhD student at Institute of Oceanology, Chinese Academy of Sciences. She has completed her Master’s Degree at the age of 25 at Lund University in Sweden. During the Master’s study, she accomplished her Master thesis project at Purdue University, School of pharmacy, working on the compounds selection of Parkinson’s disease. She is now working on the application of algae polysaccharides in Institute of Oceanology, Chinese Academy of Sciences and especially focused on the immune enhancement and anti-virus on animals. Despite being in this field for only one and a half year, she had applied two patents from Chinese Intellectual Property Office, and finished one paper writing.
Prevalence of H9N2 influenza virus has caused widespread poultry mortality in different area of the world including in China. To reduce the prevalence rate and mortality rate the administration of compounds with immunomodulatory or anti-virus effect. In this research, polysaccharides extracted from three seaweeds: Grateloupia filicina, Ulva Pertusa and Sargassum qingdaoense were studied for structural features, immunologic enhancement effect and potential antivirus effect. In the result, the ratio of total saccharide was 53.13%, 40.9% and 20.81 in Ulva Pertusa polysaccharides (UPP), Grateloupia filicina polysaccharides (GFP) and Sargassum qingdaoense polysaccharides (SCP) respectively. The monosaccharide composition was determined by high performance liquid chromatography (HPLC) and the sulfated content of UPP, GFP and SCP were 24.99%, 47.33% and 25.81%. Fourier transformation infrared (FT-IR) spectroscopy was applied to assess structure features of these three polysaccharides. Immunologic enhancement effect of the polysaccharides was evaluated both in vitro and in vivo (in mice) and anti-Avian Influenza virus (AIV)-H9N2 activity was analyzed in the Madin-Darby canine kidney (MDCK) cells. The result indicated that all three polysaccharides could stimulate the spleen cell proliferation effectively in vitro. In vivo analysis showed that polysaccharides treated groups obtained higher AIV-specific antibody titers than vaccine group and control group, especially the 50mg/kg GFP and 50mg/kg SCP stimulation groups. Meanwhile, the cytokines IFN-γ and IL-4 which can represent the immune level could be stimulated by three polysaccharides, 10mg/kg group got higher IFN-γ response than the 50mg/kg group for all three polysaccharides. While for the IL-4 level, the 50mg/kg treated groups gain better effect than the 10mg/kg groups. Furthermore, analysis of the CD3+CD4+ T-cell subpopulation level showed that 50mg/kg groups had better effect than 10mg/kg groups. Moreover, all of the three polysaccharides could significantly inhibit the activity of H9N2, via measuring the HA level and copies of H9N2. In summary, it revealed that, three polysaccharides are different in structural features, and could enhance the immune level, also have the anti-AIV- H9N2 activity both in vitro and in vivo.
Mehader Getachew is M.Sc student in Pukyong National University, Fisheries College (Department of Biotechnology), Busan, Republic of Korea. She has been working on isolation of bioactive anti-fouling compounds from different seaweed species. Currently, she is purifying anti-fouling compounds from the brown seaweed H. fusiformis.
Marine algae and invertebrates are major fouling organisms causing considerable structural and economic damage to man-made structures such as ship hulls and aquaculture nets. Most anti fouling techniques have relied on organotin or heavy metals based paints that act as broad spectrum toxins to target and non-target marine organisms. So, naturally occurring anti fouling compounds are the most promising alternatives to prevent the attachment of fouling organisms. Therefore, in this study we have investigated the anti-attachment and enhancing activities of 18 seaweed extracts against the known fouling species of red algae, Porphyra suborbiculata. At both tested concentrations of 20 and 200 µg/ mL culture medium, Hizikia fusiformis extract showed the highest inhibitory effect on the rhizoid production, rhizoid growth and germinated and juvenile blade growth. Also, extracts from Ulva pertusa, Enteromorpha linza, Undaria pinnatifida, Sargassum horneri, Ecklonia cava showed significant growth inhibition activities (P < 0.01). In contrast, the Codium fragile extract enhanced the rhizoid production with same concentrations. Also H. fusiformis methanol extract inhibited the growth of the spores from both U. pertusa and U. pinnatifida and reduced the attachment of the diatoms Naviculata annexa and Nitzchia pungens (P < 0.05). Among the five fractions isolated from the H. fusiformis extract, ethyl acetate, chloroform-methanol and chloroforml fractions have shown significant inhibitory activities against the growth of the P. suborbiculata spore. In open silca-gel-column fractionation of this extract, among the five elutes collected the highest inhibition of the P. suborbiculata spore was found in the acetonirile fraction. The isolation of the purified inhibitory compound was done by RP-HPLC at 220nm, after choosing ethanol and acetonirile as mobile phases based on RP-TLC result.