| 摘要: |
| 【目的】明确内生放线菌Hhs.015中抗菌成分的性质及其物质类型。【方法】采用皿内抗菌活性测定的方法，研究了内生放线菌Hhs.015的抑菌谱及其发酵液粗提物的理化性质，并根据纸层析、紫外吸收曲线和捷克氏八溶剂系统对活性物质进行了化学类型的早期鉴别。【结果】菌株Hhs.015对16株靶标真菌中的13种有抗性，占靶标菌总数的81.25%，抑菌谱广；其中对番茄叶霉病菌、小麦纹枯病菌、番茄灰霉病菌、苹果腐烂病菌、苹果轮纹病菌的抑制能力较强，但不抑制细菌。自然pH（pH=6.2）下，随着温度由30 ℃上升至90 ℃，Hhs.015粗提物中抗菌活性物质的稳定性有小幅下降，至90 ℃时下降了2.61%，100 ℃下保温60 min仍有较好活性，说明其具有较好的热稳定性；在偏碱性环境（pH=10.0）和酸性条件（pH=4.0）下，当温度由40 ℃上升至90 ℃时，Hhs.015粗提物对普通假丝酵母菌的抑菌圈直径降幅大于自然pH，且酸性条件下活性降低更多；在室温时，pH的变化对粗提物活性没有太大影响，紫外线对其抗菌活性影响很小。Hhs.015的活性物质粗提物在321，338和357 nm处有典型共轭五烯生色基团的吸收峰，结合纸层析和纸电泳结果，推测活性物质中含有五烯类中性抗生素。【结论】菌株Hhs.015中抗菌成分的性质比较稳定，物质的离子特性为中性，可能含有多烯类成分。 |
| 关键词: 内生菌 活性物质 稳定性 化学类型 多烯类 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（31101476）；陕西省科技计划项目（2013K01-45） |
|
| Properties and preliminary identification of antimicrobial active substances of endophytic actinomycete strain Hhs.015 |
|
YAN Xia,HUANG Yi-chao,LAN Xin,et al
|
| Abstract: |
| 【Objective】This study aimed to clarify properties of antifungal ingredients from endophytic actinomycete strain Hhs.015.【Method】Dish assay was used to evaluate the antibiotic spectrum and the factors affecting the activities of crude extracts from Hhs.015.The preliminary identification was conducted according to the paper chromatography,ultraviolet absorption curve and the Czech 8 solvent system.【Result】The bioactive substances of Hhs.015 had high inhibitory activity against 13 out of 16 target fungi (81.25%),especially to Fulvia fulva,Rhizoctonia cerealis,Botrytis cinerea,Valsa mali and Macrophoma kawatsukai.However,the bioactive substances could not inhibit bacteria.Under natural pH (pH=6.2),the antifungal activity decreased slightly as the temperature increased from 30 ℃ to 90 ℃ (2.61%).The activity remained strong after being incubated at 100 ℃ for 60 min,indicating that the substances had good thermal stability.In alkaline (pH=10.0) and acidic (pH=4.0) conditions,the antifungal ability reduced as temperature increased from 40 ℃ to 90 ℃.The decrease of inhibition zone diameter was larger than natural pH.pH had no significant effects on activity of the substances at room temperature and UV had very less effects as well.UV spectrum showed that the active crude extracts presented three typical absorbance peaks at 321,338 and 357 nm,which were typical for conjugated polyene chemicals.Combining the results of paper chromatography and paper electrophoresis,it was inferred that the active substances of strain Hhs.015 included pentaene acting as antibiotic.【Conclusion】The antimicrobial components of strain Hhs.015 were neutral and stable under different conditions.Ingredients like polyene may exist in the crude extracts. |
| Key words: endophyte bioactive substance stability chemical type polyene |
