Research On Optimum Conditions Of Pleurotus Ostreatus Protoplasts And Saccharomyces Cerevisiae Protoplasts Electrofusion

P. ostreatus, as a kind of White rot fungi, besides value in edible and medicinal, also has relationgship with degradation of lignin and cellulose, and Widely distributed in the world, it is one of the world’s edible fungus with the biggest cultivation area and highest yield. During biological treatment of straw, P. ostreatus produces and accumulates a lot of protein and other useful metabolites microbial bacteria, such as: organic acid alcohol, ester, vitamins, antibiotics and a variety of digestive enzymes. P. ostreatus also has a strong ability to degrade lignin and makes up Phanerochaete chrysosporium shortage that just degrades lignocellulose, so it can be widely used in lignin degradation system, such as crop residues. S. cerevisiae grows fast, and its metabolite contains rich superior protein, vitamins B and minerals.Lignin is the main component of plant cell wall and the key to affect the animal ability to digest plant feed. White rot fungi, is the most effective microorganism to degrade lignin. It is difficult to form the dominant population for white rot fungi, under the natural state, as a result of colonizing slowly, and the requirements of it for the fermentation condition is strict, most of the research is still limited to laboratory test at present.In this study, P. ostreatus, a kind of white-rot fungi with strong ability to degrade lignin, and S. cerevisiae who grows fast and whose metabolite contains rich superior protein, vitamins B and minerals, as parents, effects of alternating voltage、alternating electric field frequency、pulse strength、pulse number and pulse interval on P. ostreatus protoplasts and S. cerevisiae protoplasts electrofusion rate was researched through parents inactivation labeling method and Li6(45) orthogonal, then regenerative strains were screened through antagonism and morphological comparison of mycelium and identified by RAPD (Random Amplified Polymorphic DNA). The results showed that:Inactivation condition of P. protoplasts:60℃ for 10 min heat-inactivation.Inactivation condition of S. cerevisiae protoplasts:230 s UV-inactivation.The maximum fusion rate of 4.396×10-5 was achieved through 30 v alternating voltage% 1100 kHz alternating electric field frequency、6 kv/cm pulse voltage、pulse number 4 and 10 μs pulse interval. Screened three suspected fusant were all proved to be acquired from fusing P. ostreatus and S. cerevisiae protoplasts.The results showed that:similarity coefficient of S、T、G5 with P. ostreatus were higher than that with S. cerevisiae, Z and P. ostreatus have the closest relationship. This result is similar to that of mycelium morphology and antagonism.