Study of Metagenomic Sequencing Technology to Detect Microbial Contamination on the Surface of Chrysanthemi Flos

OBJECTIVE To establish a method based on metagenomic sequencing technology to detect the microbial content on the surface of Chrysanthemi Flos, detect the microbial contamination of Chrysanthemi Flos in commercially available Chinese medicine decoction pieces, and explore the ways and sources of microbial contamination. METHODS Metagenomic sequencing was used to compare the surface microbial detection differences between the cultured group and the non-cultured group of commercially available Chrysanthemi Flos samples, and the metagenomic sequencing technology was used to detect the surface microbial content of the two Chrysanthemi Flos products. Detect the surface microbe species of fresh Chrysanthemi Flos samples from Hangzhou original seed farm and Tongxiang county, and compare the species and relative content of microbes on the surface of fresh samples and commercial products. RESULTS Compared with cultured group, more fungi and archaea could be detected in the non-cultured group by metagenomic sequencing technology. Conditional pathogens were detected on the surface of both two commercial brands. Compared with fresh samples from different producing areas, more similar microbial community structure was found between the commercial samples and the fresh ones from the same producing area, which suggested that the microbial contamination mainly came from their original place. CONCLUSION Microbial contamination is present in commercial Chrysanthemi Flos samples, and the use of metagenomic sequencing in cultivation-independent samples can detect the microbial community structure. Thus, metagenomic sequencing can be considered as a powerful tool for the monitoring of microbial contamination and improving the drug safety of the Chinese herbal medicine.