海草床盐生植物根际土壤可培养细菌多样性及抑菌活性研究

he purpose of this study was to investigate the novelty and particularly of the culturable bacteria in seagrass beds and study its antibacterial activity. A total of nine rhizosphere soil samples were collected from the seagrass bed ecosystems in Pearl Bay and Yuzhouping, Fangchenggang City. Five different isolation medias were used to isolate and purify the culturable bacteria using the dilution spread plate method. The bacterial species were identified through PCR amplification and 16S rRNA sequencing. The antibacterial activity against four human pathogenic bacteria (Methicillin-resistant Staphylococcus aureus, S. epidermidis, S. aureu and Acinetobacter baumanii) were screened with Kirby-Bauer method. The results were as follows: (1)42 culturable bacteria were isolated, belonging to 14 genera and 13 families, which included Streptomyces, Vibrio, Bacillus, Shewanella, Microbacterium, Brevibacteriu, Staphylococcus, Sphingomona, Rothia, Psychrobacter, Pseudonocardia, Photobacterium, Halomonas, and Escherichia. The genus Streptomyces was the dominant bacterium. (2)Antibacterial activity showed that six bacterial exhibited strong inhibitory activity against at least two or more human pathogenic bacteria, which included Vibrio (1 bacteria), Rothia (1 bacteria), and Streptomyces (4 bacteria). The studies have shown that there are abundant resources of culturable bacterium and several bacteria has the potential antibacterial activity especially Streptomyces, which can provide a new source for the research and development of new antibiotics drugs.