| 摘要: |
| 【目的】研究食线虫性真菌Duddingtonia flagrans生长特性和不同营养要素对产孢量的影响，为其规模化发酵工艺的确定提供参考。【方法】以D. flagrans F088分离株为研究对象，研究该菌培养过程中pH值、厚垣孢子产量、菌丝干质量等指标的变化；通过单因素试验及正交试验，研究几种常见碳源、氮源、无机盐、维生素和碳氮比对厚垣孢子产量和菌丝平均生长速率的影响。【结果】供试真菌在培养2 d后进入对数生长期，4 d时达到高峰（OD600值为7.46，菌丝干质量为12.07 g/L），而pH快速下降至4.45；3 d开始产生厚垣孢子，4 d时呈爆发式增长。OD600与菌丝干质量、厚垣孢子产量呈极显著正相关，与pH呈极显著负相关。单因素试验结果表明，产生厚垣孢子的最佳碳源为白糖,氮源为大豆蛋白胨,碳氮比为40∶1,维生素为VB1、无机盐为MgSO4；菌丝生长较好的碳源为红糖,氮源为大豆蛋白胨，与对照相比，无机盐和维生素对菌丝生长无显著促进作用。4因素3水平正交试验结果显示，D. flagrans F088产生厚垣孢子和菌丝生长的最佳配方组合为：30 g/L白糖、4 g/L大豆蛋白胨、1 g/L MgSO4和30 mg/L VB1。【结论】初步明确了D.flagrans F088培养过程中pH、厚垣孢子产量、菌丝干质量等的变化趋势，确定了该菌菌丝平均生长速率和厚垣孢子产量达到最佳时的营养要素和配方组成。 |
| 关键词: Duddingtonia flagrans 食线虫性真菌 菌丝生长速率 产孢特性 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（31660708） |
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| Growth and sporulation characteristics of nematophagous fungus Duddingtonia flagrans F088 |
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CHANG Fanfan,HUANG Haiyan,LIN Guozhen,et al
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| Abstract: |
| 【Objective】This study investigated the growth characteristics and effects of different nutritional factors on sporulation of nematophagous fungus Duddingtonia flagrans F088 to provide reference for its large-scale fermentation technology.【Method】The changes of pH value,chlamydospore yield and biomass of mycelial in culture process of the strain F088 of D. flagrans were studied.By single factor test and orthogonal experiment,the effects of several common carbon sources,nitrogen sources,inorganic salts,vitamins and carbon nitrogen ratios on chlamydospore and mycelial average growth rate were also studied.【Result】The growth of fungus entered the logarithmic phase at 2 d and reached the peak at 4 d with OD600 of 7.46 and mycelial dry weight of 12.07 g/L),during which pH decreased rapidly to 4.45.The chlamydospores began to produce at 3 d and increased explosively at 4 d.Correlational analysis showed that OD600 was positively correlated with mycelial dry weight and chlamydospore yield was negatively correlated with pH.The single factor tests showed that the best carbon source,nitrogen source,inorganic salt and vitamin for chlamydospore production were white sugar,soybean peptone,MgSO4 and VB1,and the best ratio of carbon to nitrogen was 40∶1.The good carbon sources for mycelial growth were brown sugar,and good nitrogen sources were soybean peptone.No significant promoting role was observed for inorganic salts and vitamins as compared with the control (P>0.05).The orthogonal experiment of 4 factors and 3 levels showed that 30 g/L white sugar,4 g/L soybean peptone,1 g/L MgSO4 and 30 mg/L VB1 were the best combination for chlamydospores production and mycelial growth of D. flagrans F088.【Conclusion】This study preliminarily determined the changes of pH,chlamydospores production and biomass during the culture of D.flagrans F088,and the optimum nutritional formula for its mycelial average growth rate and sporulation were clarified. |
| Key words: Duddingtonia flagrans nematophagous fungi mycelial grouth rate sporulation characteristic |
