赤峰市巴林右旗地区乳及传统发酵乳制品中真菌多样性及其功能预测分析

Fungal Diversity and Functional Prediction of Milk and Traditional Fermented Dairy Products in the Bahrain Right Banner Region, Chifeng City

摘要:

该研究以赤峰市巴林右旗地区乳及传统发酵乳制品中真菌为研究对象，采用Illumina Miseq技术分析真菌多样性，并通过FUNGuild对真菌功能进行预测分析。结果显示：牛乳中的优势真菌属为Clavispora、Tirchosporon；乌如木为Geotirchum、Unclassified_f_Dipodascaceae；胡乳德为Unclassified_f_Metschnikowiaceae、Clavispora、Issatchenkia；塔拉格为Geotirchum、Dekkera、Apiotrichum、Cutaneotrichosporon、Unclassified_o_Saccharomycetales。与牛乳相比，乌如木、胡乳德、塔拉格中与致病相关的真菌属Trichosporon、Candida相对丰度下降，且有益真菌的占比增加，可见发酵能有效减少病原真菌并富集有益真菌。属水平真菌菌群组成中Geotrichum、Clavispora、Dekkera、Apiotrichum及Unclassified_o_Saccharomycetales相对丰度均存在显著差异（P<0.05）。综上所述，发酵会使真菌群落结构发生明显改变，且不同发酵工艺对乳制品真菌菌群组成的影响不同。FUNGuild基因功能预测结果表明，牛乳的主要营养模式为腐生营养型和病理营养型，包括腐生菌及动物病原菌；乌如木与胡乳德的营养模式均为腐生营养型，包括未定义的腐生菌；塔拉格的主要营养模式和牛乳相同，但包括未定义的腐生菌、土壤腐生菌、动物病原菌。该研究结果对评估巴林右旗地区乳及传统发酵乳制品的产品质量及真菌结构具有重要的参考意义。

Abstract:

Fungal diversity of milk and traditional fermented dairy products in the Bahrain Right Banner Region, Chifeng City, were determined using Illumina Miseq, and the fungal functions were predicted and analyzed using FUNGuild. The results showed that the dominant fungal genera in milk were Clavispora and Tirchosporon; those in urum were Geotirchum and Unclassified_f_Dipodascaceae; those in hurood were Unclassified_f_Metschnikowiaceae, Clavispora, and Issatchenkia; those in tarag were Geotirchum, Dekkera, Apiotrichum, Cutaneotrichosporon, and Unclassified_o_Saccharomycetales. Compared with those in milk, the fungal genera associated with pathogenicity in urum, hurood, and tarag, namely Trichosporon and Candida, were less abundant. Moreover, the relative percentages of beneficial fungi were higher in fermented dairy products, demonstrating that fermentation reduces pathogenic fungi and increases beneficial fungi. The relative abundance of Geotrichum, Clavispora, Dekkera, Apiotrichum, and Unclassified_o_Saccharomycetales exhibited significant differences (P<0.05). In summary, fermentation significantly alters the fungal community structure, and different fermentation processes have different effects on the fungal composition in dairy products. The results of FUNGuild gene function prediction indicated that the main modes of nutrition for fungi in milk were saprotrophic and pathotrophic nutrition, including saprotrophic fungi and animal pathogenic fungi. The modes of nutrition for fungi in urum and hurood were saprotrophic and included unclassified saprotrophic fungi. The main modes of nutrition for fungi in tarag were saprotrophic and pathotrophic, including undefined saprophytic fungi, soil saprotrophs, and animal pathogenic fungi. These results are important for assessing the product quality and fungal community structure of milk and traditional fermented dairy products in the Bahraini Right Banner Region.