| Cordyceps gunnii,the teleomorph of Paecilomyces gunnii,whose host insects are the larvae of Hepialidae,is a major entomogenous fungus.In this research,on the basis of intensive study of the artificial culture conditions on fruiting body of C.gunnii,the contents of several main active ingredients of fruiting body and the abilities of enriching mineral elements of P.gunnii are analyzed.This research includes strains screening,liquid culture medium screening,ascertainment of optimal culture time of flask seed,culture conditions optimization on fruiting body growth of C.gunnii by single factor experiment and orthogonal experiment,infecting non-host insects by P.gunnii using several inoculation methods,analysis of amylase,amino acids and mineral elements of three different kinds of artificial culture of C.gunnii,exploration of the abilities of enriching calcium,magnesium and zinc of P.gunnii.The experimental results indicated that the optimum culture conditions on fruiting body growth of C.gunnii were as follows: single strain Pg05S21 of P.gunnii var.minor RCEF0864 as the cultivated strain,liquid culture medium ? as the liquid shake flask culture medium,8d as the culture time of liquid shaking flask,millet as the solid cultivation substrate,nutrient solution as cultivation nutrient solution,pH6.0 cultivation nutrient solution,20 g millet and 40 mL nutrient solution per container,9mL inoculums size,25? culture temperature and continuous illumination(1~200lux).The result that the non-host insects were not successfully infected by P.gunnii should be the cause of its host specificity.Composition analysis indicated that the contents of amylase,amino acids and mineral elements in three kinds of artificial culture of C.gunnii were distinctly different.The result of the determination of amylase: amylase in mycelia from solid medium(274mg/g)was the highest and that in fruiting body(124mg/g)was significantly higher than that in mycelia from liquid medium.The content of total and total essential amino acids in mycelia from liquid medium(84.40g/100 g,31.29g/100g)was higher than these in mycelia from solid medium(81.31g/100 g,30.67g/100g)and fruiting body(64.33g/100 g,25.79g/100g).The content of calcium was determined by inductively coupled plasmaatomic emission spectrometry.The content of calcium in mycelia from solid medium(1870?g/g)was higher than that in fruiting body(1260?g/g)and mycelia from liquid medium(893?g/g).Atomic absorption spectrometer was used for determining the contents of magnesium and zinc.The content of magnesium in mycelia from solid medium(1410?g/g)was higher than that in mycelia from liquid medium(1140?g/g)and fruiting body(1080?g/g).The content of zinc in fruiting body(152?g/g)was higher than that in mycelia from solid medium(139?g/g)and mycelia from liquid medium(105?g/g).The analysis of the abilities of enriching calcium,magnesium and zinc of P.gunnii showed that the effects of enrichment were better when the content of calcium or magnesium or zinc in medium was in 10~160mg/L and the impacts on mycelia growth were little.The maximum calcium accumulation in mycelia was 16120?g/g when the content of calcium in medium was 160mg/L.When the content of calcium in medium was 120mg/L,the maximum rate of calcium accumulation of P.gunnii was 391.3%.The maximum magnesium accumulation in mycelia was 4066?g/g when the content of magnesium in medium was 120mg/L.When the content of magnesium in medium was 40mg/L,the maximum rate of magnesium accumulation of P.gunnii was 38.23%.The maximum zinc accumulation in mycelia was 5085?g/g when the content of magnesium in medium was 160mg/L.When the content of calcium in medium was 10mg/L,the maximum rate of calcium accumulation of P.gunnii was 103.78%.The analysis and comparison displayed that the ability of enriching calcium of P.gunnii was better than zinc and magnesium with the same concentration of calcium,magnesium and zinc in disparate mediums. |
PDF Full Text Request