The improvement of kinsenoside in wild-imitated cultivation Anoectochilus roxburghii associated with endophytic community

Abstract

Due to the low content of active ingredients and poor efficacy in herbal medicine in modern large-scale planting conditions, a growing number of methods for improving the content of active ingredients have been studied, such as improving planting techniques, developing and applying microbial engineering bacteria. In recent years, most studies have focused on improving the quality of Anoectochilus roxburghii through conventional farming methods. However, the role of endophytes in improving the quality of herbal medicine was often ignored. Although some studies have shown that microorganisms can regulate Anoectochilus roxburghii growth, there are still few studies on their regulation of plant active ingredients in plants. In this study, endophytic community and active ingredient content under the three culture patterns were examined through amplicon sequencing and high performance liquid chromatography-evaporative light scattering detector, and the correlation between the abundance of endophytes and kinsenoside content was analyzed. The results indicated a significant alteration in the diversity and network complexity of endophytic community within Anoectochilus roxburghii under the three culture conditions. After being cultivated in a wild-imitated environment for 3 months, the microbial composition of wild-imitated cultivated Anoectochilus roxburghii differentiated and converged toward that of wild-tending planted Anoectochilus roxburghii. Correlation analyses showed that the diversity of bacterial community has a significant positive relationship with the content of kinsenoside, and Burkholderia-Caballeronia-Paraburkholderia is the key taxa affecting kinsenoside content. In addition, acetylacetyl-CoA reductase, a key enzyme for the synthesis of kinsenoside, was significantly enriched in wild-imitated cultivated and wild tending cultivated Anoectochilus roxburghii. The study proposed that the medicinal quality of wild-imitated cultivated and wild tending cultivated Anoectochilus roxburghii, with high content of kinsenoside, which is likely attributed to the Burkholderia-Caballeronia-Paraburkholderia and acetylacetyl-CoA. This study provides a basis for the improvement and sustainable utilization of Anoectochilus roxburghii resources.