浓香型白酒窖泥梭菌的分离及其挥发性代谢产物分析

摘要

从河南张弓老酒酒业的窖泥中分离厌氧梭菌属细菌,基于微生物16S rRNA基因序列分析对分离到的细菌进行鉴定;采用顶空固相微萃取(HS-SPME)和气相色谱-质谱联用(GC-MS)技术萃取和检测了分离菌株发酵液中的挥发性代谢产物.结果表明,分离到的88株细菌与基因库中8种芽孢梭菌(Clostndium celerecrescens、C.cochlearium、C carboxidivorans、C.sporogenes、C.sartagoforme、C.thernopalmarium、C.aurantibutyric啪和C.butyricum)具有较高的序列同源性.从分离菌株的发酵液中共检测到20种酯类、12种酸类、11种醇类和4种醛类物质,还有一部分酮类和醚类物质;其中主要的酯类物质有丁酸乙酯、丁酸丁酯、3-苯丙酸乙酯等,酸类物质主要为丁酸和己酸,醇类物质主要为丁醇、己醇和3-苯丙醇.本研究有助于进一步揭示窖泥中可培养梭菌菌群对浓香型白酒风味的贡献.%Anaerobic Clostridium spp.were isolated from pit muds at Henan Zhanggong Laojiu,and identified based on 16S rRNA gene sequence analysis.The volatile metabolites of these isolates were extracted by H S-SPME and determined by GC-MS.The results suggested that the 88 bacterial strains showed high sequence similarities with 8 Clostridium spp.in GenBank,including Clostridium celerecrescens,C.cochlearium,C.carboxidivorans,C.sporogenes,C.sartagoforme,C.thermopalmarium,C.aurantibutyricum,and C.butyricum.A total of 20 esters,12 acids,11 alcohols and 4 aldehydes,and some ketones and ethers were detected from the metabolites of Clostridium spp.fermentation broth.Among them,ethyl butyrate,butyl butyrate and 3-benzene ethyl propionate were dominant esters;butyric acid and caproic acid were dominant acids;butanol,hexanol and 3-phenylpropanol were main alcohols.The study was helpful to reveal the contribution of the cultivable Clostridium spp.from pit mud to the flavor constitution of strong-flavor Baijiu (Chinese liquor).