Microbial biodiversity of raw milk collected from Yangzhou and the heterogeneous biofilm‐forming ability of Pseudomonas

Abstract

This study aimed to reveal microbial populations in Chinese raw milk using both 16S rRNA sequencing and high‐throughput sequence (HTS) methods. Psychrotrophic isolates were clustered into 23 genera and 57 species, and the abundant genera in raw milk were Pseudomonas, Acinetobacter and Lactococcus. Genetic diversity and biofilm‐forming capacity of Pseudomonas isolates were analysed using random amplified polymorphic DNA (RAPD) and crystal violet staining assay, respectively. Heterogeneous biofilm‐forming ability of Pseudomonas isolates with the same RAPD patterns was observed. HTS analysis revealed a 33‐fold higher diversity at the genus level, and a different bacterial population was predominated by Flavobacterium, Pseudomonas and Acinetobacter. The results provide insight into the microbial contamination of raw milk.