[Analysis of microbial community of heat resistant microorganisms in Chinese herbal pieces]

To investigate the composition and diversity of heat resistant microorganisms in contaminated Chinese herbal pieces. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) protein fingerprinting and 16S rRNA high-throughput sequencing of Illumina Miseq were used to analyze the heat resistant microbial community of 9 varieties of Chinese herbal pieces. Stem pieces (Spatholobi Caulis, Tetrapanacis Medulla, Stachyuri Medulla) showed highest detection rate and most species of contaminants; However fruit pieces (Schisandrae Sphenantherae Fructus) had the lowest detection rate and least species of contaminants; among root pieces, the detection rate and number of contaminants species were lower in Tuber Dioscoreae Persimilis and Rehmanniae Radix Praeparata. The heat resistant microbial community was mainly of Bacillaceae and Paenibacillaceae, and Bacillus showed the highest detection rate among them, followed by Brevibacillus, Paenibacillus, and Solibacillus. The rest genus in high-throughput sequencing analysis included Enterobacter, Brevundimonas, Leuconostoc, Methylobacterium, Dechloromonas, Pantoea, Klebsiella, and Erwinia. There were potential risk factors in heat resistant microbial community of Chinese herbal pieces, so we shall improve the microbial limit standard, strictly control the pathogenic bacteria in the product, and strengthen the supervision and management in production and circulation of Chinese herbal pieces.