Screening And Identification Of Oleaginous Fungi From The Sediments Of Deep Sea And Antarctica And Optimization Of Fermentation Conditions Of The Oleaginous Fungi

The main purposes of this paper are to study fungal diversity of Antarctic,screen oleaginous fungi from the isolated Antarctic fungi and deep sea fungi based on both Nile red staining method and TTC staining method,analy the fatty acid compositions of these oleaginous fungi and investigate the effects of medium components on lipid accumulation. The results were obtained as following:75 culturable filamentous fungi isolated form 30 collection sites sediments in Central Pacific Ocean, West Pacific Ocean and South Atlantic Ocean, including:Aspergillus sp.(27 strains)、Penicillium sp.(21 strains)、Cladosporium sp.(8 strains)、Fusarium sp.(6 strains)、Alternaria(2 strains)、Exophiala sp.(2 strains)、Engyodontium sp.(2 strains)、Acremonium sp.(1 strain)、Nectria sp.(1 strain)、Tritirachium sp.(1 strain)、Aureobasidium sp.(1 strain)、Thielavia sp.(1 strain)、Lecythophora sp.(1 strain)、Sarocladium sp.(1 strain)。Got 61 oleaginous fungi from369 deep sea fungi,they belong to 10 genera: Aspergillus(21 strains),Fusarium(13strains),Cladosporium(10 strains),Penicillium(9 strains),Engyodontium(2strains),Sarocladium(2 strains),Alternaria(1 strain),Aureobasidium(1strain),Lecythophora(1 strain) and Nectria(1 strain). The proportion of the oleaginous fungi in Antarctic is 18.70%.The strains from Aspergillus are in a largest number, the total content is 30.43%,and the are Fusarium(18.84%),Cladosporium(14.49%) and Penicillium(13.04%).In the 29 th Chinese Antarctic scientific expedition,23 sediment samples were collected from Prydz Bay. A total of 21 fungal strains were isolated from the sediment samples and these fungi belong to 11 genera based on fungal ITS sequence analysis,including: Penicillium(9 strains),Cladosporium(3 strains),Acremonium(1 strain),Aureobasidium(1 strain),Botryotinia(1 strain),Eurotiales(1 strain),Exophiala(1strain),Fusarium(1 strain), Nectria(1 strain), Phoma(1 strain) and Sarocladium(1strain). The fungi of Antarctic have abundant diversity. The total content of the strains from Penicillium is 42.85%,in a largest number,and the total content of the strainsfrom Cladosporium is 14.29%.Eight oleaginous fungi were obtained from the isolated Antarctic fungi based on both Nile red staining method and TTC staining method. The oleaginous fungi belong to 7 genera, including Penicillium(2strains),Aureobasidium(1 strain),Cladosporium(1 strain),Eurotiales(1strain),Exophiala(1 strain),Fusarium(1 strain) and Sarocladium(1 strain). The proportion of the oleaginous fungi in Antarctic is 38%.Fatty acid composition analysis of intracellular lipids showed that fatty acids occurred in the range C16-C18 for most oleaginous fungi. A relative high proportion of unsaturated fatty acids were observed in the lipid contents, suggesting that these oleaginous fungi have potential for biodiesel production.Selected one oleaginous fungi(P7-07-M1) from Antarctic oleaginous fungi and two oleaginous fungi(JL7KGC01A-M7 and MP4CTD-11-M5) from deep sea oleaginous fungi as the target bacteria to investigeta the effects of medium components on lipid accumulation.The results showed that: Optimization of media resulted in a 27.89% increase in the lipid yield of P7-07-M1 after cultivation for 8days. The best nitrogen source of culture medium was peptone,and the best carbon source was glucose,the optimization medium components are:The C/N molar ratio is168, the concentration of Cu SO4.5H2 O is 0.0001g/L and the concentration of Mn SO4.H2 O is 0.004g/L; Optimization of media resulted in a 30.15% increase in the lipid yield of JL7KGC01A-M7 after cultivation for 67 days,the optimization medium components are:The C/N molar ratio is 140, the concentration of Cu SO4.5H2 O is0.0002g/L and the concentration of Mn SO4.H2 O is 0.003g/L; Optimization of media resulted in a 111.16% increase in the lipid yield of MP4CTD-11-M5 after cultivation for 7 days,the optimization medium components are:The C/N molar ratio is 140, the concentration of Cu SO4.5H2 O is 0.0001g/L and the concentration of Mn SO4.H2 O is0.004g/L.The strain MP4CTD-11-M5 achieved the largest enhance.