Studies On Optimizing The Fermentation Conditions Of Ganoderma Applanatum And The Antimicrobial Activities Of Its Products

Ganoderma applanatum belongs to Basidionmycota, Basidiomycetes, Ganodermatales and Ganodermataceae. G. applanatum is a Chinese medicine food homologous. Researches demonstrated that it is bitter and has many pharmacological actions, such as anti-tumor, relieve pain, suppression of inflammation and so on. In recent years, there is a large demand for G. applanatum. G. applanatum becomes much more popular to exploit fungi resources. The submerged and solid fermentation conditions, the extraction conditions and antimicrobial activity of G. applanatum from the city of LeYe, GuangXi province were studied. The main research results showed as follows:1. The fruit body of G. applanatum was discovered by our investigation in LeYe, GuangXi. It was collected from the rotten wood in doline. The strain was separated and cultivated with tissue separating. The strain was identified as G. applanatum by morphology and references.2. The effect of nutrient demands on mycelia biomass was studied respectively by single factors experiment. The experimental results showed that the optimum formula of liquid culture medium were corm flour 40 g/L, soybean powder 15 g/L, KH2PO4 3 g/L, MgSO4 1.5 g/L, VB1 20 mg/L. The optimum flask culture conditions were seed age 6 days, vaccination size 4%, agitation speed 150r/min, culture temperature 28℃, medium capacity 80/250mL, culture time 6 days, initial pH value 6. Under the optimum liquid fermentation culture conditions, the dry weight of mycelia reached 12.2 g/L3. The effect of carbon source, nitrogen source, salt and the optimum initial pH of medium etc. factors on the production of ex-cellular polysaccharide were studied separately. The liquid fermentation mediums were as follows:sucrose 50 g/L, soybean powder 10 g/L, KH2PO4 4.5 g/L, MgSO4 1.5 g/L, VB1 30 mg/L. The optimum culture conditions were seed age 6 days, vaccination size 5%, agitation speed 150 r/min, culture temperature 28℃, medium capacity 100 mL/250mL,15 pieces of glass beads, culture time 9 days, initial pH value 6. Under the optimum liquid fermentation culture conditions, the extra-cellular polysaccharide production reached 3.4 g/L.4. Selected the optimum medium and culture conditions of solid fermentation on polysaccharide. The results showed:rice husk and wheat bran as medium and its quality ratio was 2 to 1, the other ingredients of solid fermentation medium were: sucrose 25 g/kg, soy bean powder 5 g/kg, CaCl2 4.8 g/kg, MgSO45 g/kg, VB1 20 mg/kg. The optimum culture conditions were culture temperature 28℃, vaccination size 5%, culture time 15 days, substrate moisture content 60%, the initial pH value 6. Under the optimum solid fermentation culture conditions, the produciont of polysaccharide reached 6.47 g/kg.5. The extract technology of solid fermentation polysaccharide was developed in this experiment, the results was distilled water as extract solvent, the radio of substance and water 30:1, extract temperature 75℃, extract duration for 2.5 h, extract 2 times. After optimization of the extract process, the yield of polysaccharide was increased by 16.3%, the polysaccharide reached 7.51 g/kg.6. With filter paper disk method and tube double dilution method, the antimicrobial activities of petroleum ether, chloroform, ethyl acetate, water extract of liquid fermentation mycelium and broth, extro-cellular polysaccharide and polysaccharide of solid fermentation on Escherichia coli, Staphylococcus aureus, Bacilhus subtilis, etc. ten strains. The result shows that the extracts of with different solvents had different antimicrobial activities. The extract of chloroform, ethyl acetate, of liquid fermentation mycelium and broth had evident antimicrobial effect. The extract of ethyl acetate of broth indicated the best antimicrobial effect and its average diameter of inhibited halo was 19.6 mm. Then it was elution to 9 fractions. The B5 fraction had the best antimicrobial activity. Its MIC to Micrococcus luteus was 25mg/mL, its MIC to Escherichia coli, Staphylococcus aureus, Bacilhus subtilis, Proteus was 50mg/mL, its MIC to Candida albicans was 100mg/mL, its MIC to yeast was 200mg/mL, its MIC to Aspergillus niger, Aspergillus oryzae, Trichoderma was 400mg/mL. 7. The chemical constituents of fermentation broth were studied by the methods of sillica gel column chromatography, TLC, recrystallization etc.. After sepearation and purifiction,β-sitosterol was obtained.