Rhizosphere microorganisms from the soil around the roots of Lycium barbarum L.

Abstract

Plant of Lycium barbarum L., in Chinese name of “Goqi” tree, produce very important traditional Chinese medicine of Goqi berries for clinical application over 2000 years in China. In the early stage, people conducted extensive research on the bioactive components, planting methods, and deep processing of L. barbarum L., yet paid scant attention to the rhizosphere microorganisms surrounding their roots. In this context, the rhizosphere soil of L. barbarum L., collected in Ningxia province of China, was studied to investigate the microbial diversity by performing 16S rRNA/ITS sequencing, which led to identify 29 strains including 9 bacteria and 20 fungi. On the bases of the GNPS analysis of HPLC-q-ToF MS data of the fermentation broth, rich secondary metabolites were identified from twenty microorganisms. The molecular network clustering analysis suggests that the fermentation broth of bacteria may contain 607 compounds and that of fungi may contain 1359 compounds, involving multiple types. Antibacterial activity evaluation results revealed that rhizosphere microorganisms had inhibitory effects on Staphylococcus aureus and Candida albicans. This article lays a scientific foundation for the utilization of soil biological resources in L. barbarum L. cultivation and paves the way for the discovery of novel antibacterial active substances with unique structures.