Influence of tissue and geographic locality on culturable endophytic bacteria of Atractylodes macrocephala

Abstract

The endophytic bacterial community and their diversity are closely related to the host’s growth and development. This paper explores the culturable endophytic bacteria in the stems, leaves, roots and rhizomes of Atractylodes macrocephala (AM) of four localities (Yuqian, Wenxian, Pan’an and Pingjiang) and the potential correlation between the bacteria and plant bioactive compounds. A total of 118 endophytic bacteria belonging to 3 phyla, 5 classes, 11 orders, 26 families and 48 genera were isolated and identified from the four AM tissues. Among them, Bacillus was the dominant genus. In AM, the tissue type and locality influenced the endophytic bacterial community. Approximately 29.7 and 28.8% of the endophytic bacteria exhibited tissue specificity and geographic specificity, respectively. Furthermore, high-performance liquid chromatography revealed that the sesquiterpenoid (atractylenolide I, atractylenolide Ⅱ and atractylon) content was more in the rhizomes of Wenxian than in those of Pingjiang, Yuqian and Pan’an. The multiple linear regression was used to screen the bacterial strains related to the bioactive compounds of AM. The relative frequency of Microbacterium positively correlated with atractylenolide I and atractylon content in AM but negatively correlated with atractylenolide Ⅱ content. The study also provides a theoretical framework for future research on endophytic bacteria as alternative sources of secondary plant metabolites.

Microbial fortification of pharmacological metabolites in medicinal plants

“…Similarly, geographic specificity was observed for both the microbiome and the sequiterpenoid contents of Atractylodes macrocephala Koidz. , which is a herbaceous medicinal plant used in traditional Chinese medicine formulations to invigorate the spleen [28] . The microbial enhancement of C. reticulate monoterpene production was attributed to the higher expression levels of some genes related to terpenoid biosynthesis and modifications [25] .…”

Cultivable Endophyte Resources in Medicinal Plants and Effects on Hosts

“…Atractylodes macrocephala Koidz., called Baizhu in Chinese, is a medicinal plant used in traditional Chinese medicine theoretical systems to treat gastrointestinal dysfunction, cancer, osteoporosis, obesity and other symptoms, and has various pharmacological activities [ 15 ]. Wu et al [ 16 ] explored the cultivable endophytic bacteria in the stems, leaves, roots, and rhizomes of Atractylodes macrocephala Koidz. in four different regions and their potential correlation with plant bioactives.…”