Studies On The Secondary Metabolites Of Two Marine Fungi And Culture Condition Optimization For C2A

Because of their unique living environment, marine fungi have the potency to produce novel structural secondary metabolites with varied skeletons and bioactivities, these natural bioactive compounds have become an important source in research and development of drugs.There are two parts of researches in this thesis.Firstly we chose two marine fungi strains to study their secondary metabolites. In total, thirteen compounds were isolated and elucidated with various chromatograph and spectrum methods. From Penicillium Penicillium sp. ML-226, nine compounds were identified, including sterol compounds (MYL-1,MYL-4), furan derivatives (MYL-10,MYL-15), anthraquinone derivatives (MYL-39), diphenyl ketone compounds (MYL-23,MYL-5), benzoic acid benzene ester compounds(MYL-37), two ketone piperazine compounds (MYL-29). It’s possible that MYL-37and MYL-5were identified for the first time.From the strain0221-018, four compounds were separated and identified, they are sterol compound (KL-1), macrolide compounds (KL-6,KL-10), dihydroxy benzoic acid lactone compounds (KL-7). KL-7and KL-10are possible to be new compounds.Meanwhile,we tested the bioactivities of some isolated compounds. Unfortunately, they didn’t show any antitumor activity, while MYL-23have modium activity against B.p and B.s;compound KL-4showed certain antibacterial activity against B.s. Determination of antioxidant activity showed that four new compounds showed a certain activity.Secondly, fermentation conditions of compound C2A were optimized for its yield. C2A is a potential lead compound with unique bioactivity isolated by our lab. Through studying multiple basic media, and different fermentation courses, design with Plackett-Burman method, optimizing with single-factor and response surface methods, the best fermentation solid medium composition for C2A is found to be potato400g/L, glucose35g/L, peptone10.5g/L,(NH4)2SO40.6g/L, and the best fermentation condition is28℃for10d. Under this condition, the yield of C2A reached4mg/L, much higher than before.