菌株F75风化煤降解特性研究

摘要

[Objective] Microbes can effectively improve the conversion efficiency of weathered coal.Due to the differences of geographical condition and age,weathered coals usually showed different physical and chemical properties,which affected the degradation of microbes.Therefore,the definition of degradation characteristics of different weathered coals could effectively improve its conversion efficiency.[Method]In this study,taken Three different sources of weathered coal as tested materials,the strain ' F75 ' was screened and identified,which could degrade weathered coal.[Result] Under the solid and liquid culture,the degradation characteristics of the contents and structure of humic acids of the strains from weathered coals were analyzed.The strain ' F75' could degrade the three sources of weathered coals and was identified as Aspergillus niger.Under the liquid culture,the UV analysis showed that the curves of F75 to the YF01 and YF09 increased firstly and then decreased from 190 nm to 280 nm,whereas the curve of F75 to the YF06 increased in this stage,and all the weathered coals showed obvious enhancement before 205 nm.The results of FT-IR showed that under the action of YF01,the carbon chain of F75 was shortened,with higher rate of weight loss,and for the YF06 and YF09,the content of water-soluble humic acid and fulvic acid increased,which implied that the effect of F75 to YF06 and YF09 concentrated in the carboxyl groups.Under the solid culture condition,the content of free humic acid of YF06 significantly increased when F75 was added;The content of water soluble humic acid and fulvic acid of three weathered coals significantly increased with F75 addition,of which the increase of water soluble humic acid had a dominant effect on YF09 and some consumption effect on YF06.[Conclusion] During the degradation of different sources of weathered coals according to the rate of weight loss and the content of humic substances,the strain had different dominant effects,which would guide the further transformation of weathered coal.%[目的]利用微生物能有效提高风化煤类物质的转化效率.由于地理环境和形成年代及条件的差异,使得风化煤理化性质差异较大,直接影响了微生物的降解作用,所以明确微生物菌株对不同风化煤的降解特性能有效提高其转化效率.[方法]本研究以3个不同来源的风化煤样为研究材料,筛选了具有降解作用的微生物菌株F75并进行鉴定.[结果]在固体和液体培养条件下,从风化煤样的各腐植酸含量及结构的变化上分析菌株对其的降解特性.菌株F75对3个风化煤样均有降解作用,经鉴定为黑曲霉.液体培养条件下,风化煤YF01和YF09在190～ 280 nm的吸收曲线较对照呈现先增加后减少的趋势,而风化煤YF06则呈现较对照一直增加的趋势,且3个风化煤样均在小于205 nm时有明显的加强.红外光谱分析显示菌株F75对风化煤YF01的作用集中在碳链的缩短上,表现为失重率较高;对风化煤YF06和YF09的作用集中在羧基官能团上,表现为水溶性腐植酸和黄腐酸含量的增加.固体培养条件下,菌株F75对风化煤YF06的游离腐植酸含量提高明显;菌株F75对3个风化煤样的水溶性腐植酸含量和黄腐酸含量均有明显提高,其中对风化煤YF09中水溶性腐植酸含量的增加呈主导作用,而对风化煤YF06中黄腐酸的含量有一定的消耗作用.[结论]菌株降解风化煤的作用在失重率和腐植酸类物质含量上因不同的风化煤样而存在不同的主导作用,可以指导风化煤进一步的转化生产.