燕麦甜醅真菌群落多样性及米根霉发酵对甜醅性质的影响

Fungal Diversity of Traditional Oats Tianpei and the Fermentation Effects of Rhizopus Oryzae on Tianpei Properties

利用Illumina测序技术对我国西北地区5种代表性燕麦甜醅样品进行了真菌多样性研究。研究发现燕麦甜醅样品中,毛霉菌门(Mucoromycota)和子囊菌门(Ascomycota)类群丰度最高,还有少量担子菌门(Basidiomycota)类群。在属水平,根霉属(Rhizopus)含量最高,其次是未能准确分类的子囊菌类群(unclassified_p_Ascomycota)、酵母菌属(Saccharomyces)和伊萨酵母属(Issatchenkia)。主成分分析(PCA)表明5种燕麦甜醅样品具有不同真菌群落结构。通过线性判别分析(Lefse)找出了甜醅样品的真菌生物标志分类单元,包括毛霉(Mucor)和毕赤酵母(Pichia)等。甜醅真菌组成与甜醅所含化学成分(乳酸、游离脂肪酸、氨基酸、还原糖等含量)显著相关。并研究了米根霉发酵对甜醅化学成分的影响。米根霉发酵显著提高了甜醅化学成分含量。上述结果为我国传统发酵全谷物甜醅微生物区系研究、相关微生物资源发掘、甜醅产品改性及品质提升等提供了理论依据。

The fungal diversity of five sweet fermented oats samples in China was studied by Illumina sequencing.The results showed that the abundance of Mucoromycota and Ascomycota peaked in the oats Tianpei samples, and a bit Basidiomycota were also included. As to genus, Rhizopus had the highest abundance, followed by unclassified_p_Ascomycota, Saccharomyces and Issatchenkia. Principal component analysis (PCA) indicated that five kinds of oats Tianpei samples formed their own fungal clusters. The biomarker taxa of oats Tianpei were identified by Lefse, including Mucor and Pichia. The fungal composition of oats Tianpei was significantlly related to the chemical composition of oats Tianpei (lactic acid, free fatty acid, amino acid, reducing sugar, etc). The fermentation effects of Rhizopus oryzae on the chemical composition of oats Tianpei were studied also. The fermentation of Rhizopus oryzae significantly increased the chemical composition in oats Tianpei. The research provided a theoretical basis for the study of microbial flora, the discovery of related microbial resources, the fermented modification grains, and the improvement of oats Tianpei quality.