Studies On Screening Of Marine Fungi With Anti-MRSA Activity And The Active Compounds Produced By Strain W0707

With the wide use of antibiotics and other antibacterial agents, bacteria resistant to many antibiotics is increasing seriously, for example, Methicillin-resistant Staphylococcus aureu(sMRSA) which is resistant to most antibiotics is increasing rapidly and has become the vital pathogenic bacteria in the clinic. A renewed effort should be made to seek new antibiotics against MRSA. Microorganism resources in land once were the main source for screening for antibiotic. However, with the research going on, it is becoming more and more difficult to find new antibiotics. It is necessary to seek for the new medicine source. Since the specific living environment, marine microorganisms have unique heredity background and metabolite pathways, and may synthesize some distinct antibiotics in structures. Therefore it has significance for antibiotics screening from marine microorganism.In this paper, 29 selected marine environment speciments were collected from Island of Hainan, Zhanjiang and Beihai , research was carried out on the isolation of marine fungi and screening for strains with anti-MRSA active compounds. Strain W0707 possessed higher stability and repeatability of activity against MRSA, and was further studied. Using seven culture media, marine fungi were isolated from marine sponge and marine algae collected from Sanya by the method of dilution. The results showed that medium A containing 2% sucrose,0.5% K2HPO4,1% peptone, 10% potato, 100 U·mL-1 penicillin and streptomycin respectively with initial pH6.5 was the best media for marine fungi isolation. Utilizing the aforesaid medium, amounts to 312 fungi were isolated from 29 marine samples, which were collected from island of Hainan, Zhangjiang and Beihai. 22 fungi isolates with anti-MRSA active compounds were obtained by the method of Kirby Bauer.A fungus strain W0707 was isolated from marine sponge collected from Qionghai was found to produce antibiotics. By studying the morphology, 18S rDNA and phylogenetic tree, strain W0707 was proposed as Aspergillus terreus W0707. The GenBank accession number for the 18S rDNA gene sequence of strain W0707 is DQ489561.