不同生境银柴胡根内生菌群落特征及其与药材主要有效成分、产量的相关性分析

Correlations of endophytic microbial community with main active components and yield of Stellaria dichotoma var. lanceolata in different habitats

摘要:

【背景】银柴胡（Stellaria dichotoma var.lanceolata）具有重要的临床药用价值，其总甾醇和总黄酮含量是评价药材的关键。【目的】探究药用植物银柴胡在不同生境下根内生菌群落特征及其与药材主要成分、产量之间的关系。【方法】采用高通量测序技术和药材常规测定方法，分析了风沙土（semi-fixed aeolian sandy soil，SFA）生境、石砾质土（lithosol，LI）生境和黄绵土（loessal，LO）生境银柴胡根内生菌群落特征及其与药材性状响应关系。【结果】各生境银柴胡内生优势细菌门为放线菌门（Actinobacteriota）和变形菌门（Proteobacteria），优势真菌门为子囊菌门（Ascomycota）和担子菌门（Basidiomycota），而内生优势菌属因生境不同各不相同；银柴胡药材主要有效成分总甾醇和总黄酮含量在LI生境中较高，而单株干重和干鲜比在SFA生境中较高。Spearman相关性分析表明，与银柴胡药材有效成分及产量显著正相关的内生菌相对较多。综合比较，内生细菌如metagenome_g__norank_f__67-14和内生真菌如unclassified_p__Ascomycota等更为显著。【结论】与银柴胡药材关键活性成分相关的内生菌群落在种类鉴定和提取、菌种培养和次生代谢物分析等方面具有广阔的研究价值。本研究为银柴胡道地产区药材高质量产业发展提供理论参考。

Abstract:

[Background] Stellaria dichotoma var. lanceolata has an important medicinal value, and its quality can be evaluated based on the total sterols and total flavonoids. [Objective] To explore the endophytic microbial community characteristics in the root of S. dichotoma var. lanceolata growing in different habitats and the relationship of the microbial community structure with the main components and yield of the medicinal herb. [Methods] We employed the high-throughput sequencing and conventional determination methods of medicinal materials to analyze the characteristics of the endophytic microbial community in the roots of S. dichotoma var. lanceolata in different habitats of semi-fixed aeolian sandy soil (SFA), lithosol (LI), and loessal (LO). [Results] The dominant endophytic bacteria were Actinobacteriota and Proteobacteria, and the dominant fungi were Ascomycota and Basidiomycota. The dominant endophytic microbial genera varied depending on the habitats. The content of total sterols and total flavonoids was higher in the LI habitat, while the dry weight per plant and the dry weight-to-fresh weight ratio were higher in the SFA habitat. Spearman correlation analysis suggested that there were rich endophytes represented by metagenome_g__norank_f__67-14 (endophytic bacteria) and unclassified_p__Ascomycota (endophytic fungi) showing significantly positive correlations with the main medicinal components and yield of S. dichotoma var. lanceolata. [Conclusion] The endophytic microbial taxa associating with the key active components of S. dichotoma var. lanceolata have a broad research value in species identification and extraction, strain culture, and secondary metabolite analysis. This study provides a theoretical reference for the development of high-quality medicinal materials in the suitable producing areas of S. dichotoma var. lanceolata.