AUTHOR=Zhang Xin-Guo , Guo Si-Jia , Wang Wen-Na , Wei Guo-Xing , Ma Guo-Yan , Ma Xiao-Di 

TITLE=Diversity and Bioactivity of Endophytes From Angelica sinensis in China

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.01489

DOI=10.3389/fmicb.2020.01489

ISSN=1664-302X

ABSTRACT=<p>Plant seeds are not merely reproductive organs, they are also carriers of microorganism, particularly, inherent and non-invasive characteristic endophytes in host plant. Therefore, in this study, the endophytic diversity of <italic>Angelica</italic> seeds was studied and compared with endophytes isolated from healthy leaves, stems, roots, and seeds of <italic>A</italic>. <italic>sinensis</italic> using 20 different media. The metabolites of endophytic strains were evaluated with six different methods for their antioxidant activity and the paper disc diffusion method for antimicrobial activities. As a result, 226 endophytes were isolated. Compared with the biodiversity and abundance of uncultured fungi from <italic>Angelica</italic> seed, the result showed that the most frequent endophytic fungi were <italic>Alternaria</italic> sp. as seen in artificial media; moreover, compared with artificial media, the pathogenic fungi, including <italic>Fusarium</italic> sp. and <italic>Pseudallescheria</italic> sp., were not found from the <italic>Angelica</italic> seed, the results suggested it may not be inherent endophytes in plants. In addition, bacteria from seven phyla were identified by high-throughput sequencing, while five phyla of endophytic bacteria were not isolated on artificial media including <italic>Proteobacteria</italic>, <italic>Actinobacteria</italic>, <italic>Bacteroidetes</italic>, <italic>Microgenomates</italic>, and <italic>Saccharibacteria</italic>. Furthermore, the sample JH-4 mycelium displayed the best antioxidant activity, and the active constituent may be a flavonoid as determined by total phenol and flavonoid content. Moreover, YH-12-1 mycelium had strong inhibitory activity against the five tested strains and the minimum inhibitory concentration (MIC) against <italic>Pseudomonas aeruginosa</italic> and <italic>Streptococcus pneumoniae</italic> was found to be 25 μg/mL. Our results confirm that plant endophytes are rich in biodiversity and contain important resource of many uncultured microorganisms.</p>