Isolation,Purification And Identiilcaton Of Medium Chain Peptaibols-trichokonin B And Scale-up Production Of Trichokonin ? From Trichoderma Longibrachiatum SMF2

Trichoderma species are ubiquitous fungi in the soil,root and foliar environments.Trichoderma spp.exhibited broad spectrum inhibition activities against a varity of phytopathogens and became one of the most important biological control agents.The bio-control mechanisms include antibiosis,competition effect,hyperparasitism,and inducing plant resistance.Antibiosis is one of the most important inhibition mechanism of Trichoderma spp.,and peptaibols are important secondary metabolites antibiosis,which are peptide secondary metabolites rich in a-aminoisobutyric acid(Aib)from filamentous fungi,especially by the members of the genus Trichoderma.In our previous study,we found T.longibrachiatum SMF2 is a good candidate for controlling plant diseases,which can inhibit a range of plant phytopathgens.The active secondary metabolites from SMF2 were thermostable and identified as Trichokonins(Trichokonin ?.? and ?),a member of peptaibols with 20 amino acid residues.Trichokonins exhibit antimicrobial,antiviral activities,induce tumor cell apoptosis and induced resistance in plants(Song et al.,2006;Shi et al.,2010;Luo et al.,2010).In our previous study,we also found that T.longibrachiatum SMF2 secreted several other lower abundance antimicrobial substances with.In this stuy,we used gel chromatography and high performant liquid chromatography to purify these low abundance substances.Six antimicrobial components were purified and identified as Trichokonin B(Trichokonin B-1,Trichokonin B-2,Trichokonin B-3,Trichokonin B-4,Trichokonin B-5,Trichokonin B-6)by ESI-MS/MS,peptaibols with 11 amino acid residues.These Trichokonin B showed typical microheterogeneity of peptaibols,which are only distinguished by exchange of single or two amino acids residues.Trichokonins exhibited a varity of biological activites and has the potential in argriculture and pharmaceutical industry.Therefore we scaled up and optimized the culture conditions for Trichokonins production under solid-state fermentation.The maximum yield was achieved by employing temperature 30?,initial moisture content 45%,inoculum 4 ml,0.5%of aib,phosphate concentration 1.8%w/w with coarse size of rice husk.The maximum yield was achieved when speed of wind was 0.5 L/min,rotational speed was 2 rpm,reflux frequency was 10 s-1 in bioreactors.