Comparative analysis in different organs and tissue-specific metabolite profiling of Atractylodes lancea from four regions by GC-MS and laser microdissection

Comparative analysis of the rhizosphere microbiome and medicinally active ingredients of Atractylodes lancea from different geographical origins

This study aimed to explore the important role of the rhizosphere microbiome in the quality of Atractylodes lancea (Thunb.) DC. (A. lancea). The rhizosphere microbial community of A. lancea at two sampling sites was studied using metagenomic technology. The results of α-diversity analysis showed that the rhizosphere microbial richness and diversity were higher in the Maoshan area. The higher abundance of core microorganisms of the rhizosphere, especially Penicillium and Streptomyces, in the Maoshan area compared with those in the Yingshan area might be an important factor affecting the yield of A. lancea. Redundancy analysis illustrated that the available phosphorus had a significant effect on the rhizosphere microbial community structure of A. lancea. We also showed that the plant-microbe and microbe-microbe interactions were closer in the Maoshan area than in the Yingshan area, and Streptomyces were the main contributors to the potential functional difference between the two regions. A. lancea in the Maoshan area had a high content of atractylodin and atractylon, which might be related to the enhanced abundance of Streptomyces, Candidatus-Solibacter, and Frankia. Taken together, this study provided theoretical insights into the interaction between medicinal plants and the rhizosphere microbiome and provides a valuable reference for studying beneficial microbes of A. lancea.

Induction and metabolomic analysis of hairy roots of Atractylodes lancea

Atractylodes lancea is an important source of traditional Chinese medicines. Sesquiterpenoids are the key active compounds in A. lancea, and their presence determines the quality of the material. Hairy hoot (HR) culture is a potential method to produce medicinally active compounds industrially; however, the induction and metabolic profiling of A. lancea HR have not been reported. We found that optimal induction of A. lancea HR was achieved by Agrobacterium rhizogenes strain C58C1 using the young leaves of tissue culture seedlings in the rooting stage as explants. Ultra-performance liquid chromatography-tandem mass spectrometric analyses of the chemical compositions of HR and normal root (NR) led to the annotation of 1046 metabolites. Over 200 differentially accumulated metabolites were identified, with 41 found to be up-regulated in HR relative to NR and 179 down-regulated in HR. Specifically, atractylodin levels were higher in HR, while the levels of β-eudesmol and hinesol were higher in NR. Metabolic pathway analyses showed a significant difference in metabolites of the shikimate acid pathway between HR and NR. Five A. lancea compounds are potential biomarkers for evaluation of HR and NR quality. This study provides an important reference for the application of HR for the production of medicinally active compounds. KEY POINTS: • We established an efficient protocol for the induction of HR in A. lancea • HR was found to have a significantly higher amount of atractylodin than did NRs • Metabolic pathway analyses showed a significant difference in metabolites of the shikimate acid pathway between HR and NR.

Authenticating the geographic origins of Atractylodes lancea rhizome chemotypes in China through metabolite marker identification

Introduction

Atractylodes lancea is widely distributed in East Asia, ranging from Amur to south-central China. The rhizome of A. lancea is commonly used in traditional Chinese medicine, however, the quality of products varies across different regions with different geochemical characteristics.

Method

This study aimed to identify the chemotypes of A. lancea from different areas and screen for chemical markers by quantifying volatile organic compounds (VOCs) using a targeted metabolomics approach based on GC-MS/MS.

Results

The A. lancea distributed in Hubei, Anhui, Shaanxi, and a region west of Henan province was classified as the Hubei Chemotype (HBA). HBA is characterized by high content of β-eudesmol and hinesol with lower levels of atractylodin and atractylon. In contrast, the Maoshan Chemotype (MA) from Jiangsu, Shandong, Shanxi, Hebei, Inner Mongolia, and other northern regions, exhibited high levels of atractylodin and atractylon. A total of 15 categories of VOCs metabolites were detected and identified, revealing significant differences in the profiles of terpenoid, heterocyclic compound, ester, and ketone among different areas. Multivariate statistics indicated that 6 compounds and 455 metabolites could serve as candidate markers for differentiating A. lancea obtained from the southern, northern, and Maoshan areas.

Discussion

This comprehensive analysis provides a chemical fingerprint of selected A. lancea. Our results highlight the potential of metabolite profiling combined with chemometrics for authenticating the geographical origin of A. lancea.

Screening for Neuroprotective and Rapid Antidepressant-like Effects of 20 Essential Oils

Depression is a serious psychiatric disorder with high prevalence, and the delayed onset of antidepressant effects remains a limitation in the treatment of depression. This study aimed to screen essential oils that have the potential for rapid-acting antidepressant development. PC12 and BV2 cells were used to identify essential oils with neuroprotective effects at doses of 0.1 and 1 µg/mL. The resulting candidates were treated intranasally (25 mg/kg) to ICR mice, followed by a tail suspension test (TST) and an elevated plus maze (EPM) after 30 min. In each effective essential oil, five main compounds were computationally analyzed, targeting glutamate receptor subunits. As a result, 19 essential oils significantly abolished corticosterone (CORT)-induced cell death and lactate dehydrogenase (LDH) leakage, and 13 reduced lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). From in vivo experiments, six essential oils decreased the immobility time of mice in the TST, in which Chrysanthemum morifolium Ramat. and Myristica fragrans Houtt. also increased time and entries into the open arms of the EPM. Four compounds including atractylon, α-curcumene, α-farnesene, and selina-4(14),7(11)-dien-8-one had an affinity toward GluN1, GluN2B, and Glu2A receptor subunits surpassed that of the reference compound ketamine. Overall, Atractylodes lancea (Thunb.) DC and Chrysanthemum morifolium Ramat essential oils are worthy of further research for fast-acting antidepressants through interactions with glutamate receptors, and their main compounds (atractylon, α-curcumene, α-farnesene, and selina-4(14),7(11)-dien-8-one) are predicted to underlie the fast-acting effect.

Geographic Differentiation of Essential Oil from Rhizome of Cultivated Atractylodes lancea by Using GC-MS and Chemical Pattern Recognition Analysis

The rhizome of Atractylodes lancea (RAL) is a well-known Chinese herbal medicine (CHM) that has been applied in clinical settings for thousands of years. In the past two decades, cultivated RAL has gradually replaced wild RAL and become mainstream in clinical practice. The quality of CHM is significantly influenced by its geographical origin. To date, limited studies have compared the composition of cultivated RAL from different geographical origins. As essential oil is the primary active component of RAL, a strategy combining gas chromatography-mass spectrometry (GC-MS) and chemical pattern recognition was first applied to compare the essential oil of RAL (RALO) from different regions in China. Total ion chromatography (TIC) revealed that RALO from different origins had a similar composition; however, the relative content of the main compounds varied significantly. In addition, 26 samples obtained from various regions were divided into three categories by hierarchical cluster analysis (HCA) and principal component analysis (PCA). Combined with the geographical location and chemical composition analysis, the producing regions of RAL were classified into three areas. The main compounds of RALO vary depending on the production areas. Furthermore, a one-way analysis of variance (ANOVA) revealed that there were significant differences in six compounds, including modephene, caryophyllene, γ-elemene, atractylon, hinesol, and atractylodin, between the three areas. Hinesol, atractylon, and β-eudesmol were selected as the potential markers for distinguishing different areas by orthogonal partial least squares discriminant analysis (OPLS-DA). In conclusion, by combining GC-MS with chemical pattern recognition analysis, this research has identified the chemical variations across various producing areas and developed an effective method for geographic origin tracking of cultivated RAL based on essential oils.

Full-length transcriptome analysis of two chemotype and functional characterization of genes related to sesquiterpene biosynthesis in Atractylodes lancea

Atractylodes lancea (Thunb.) DC. is an important medicinal plant mainly distributed in China. A. lancea is rich in volatile oils and has a significant effect on various diseases, including coronavirus disease 2019 (COVID-19). Based on the signature constituents of volatile oils, A. lancea is divided into two chemotypes: the Dabieshan and Maoshan chemotype. Gas chromatography-mass spectrometry (GC-MS) results revealed that the hinesol and β-eudesmol contents in the Dabieshan chemotype were higher than those in the Maoshan chemotype. Next-generation sequencing (NGS) and single-molecule real-time (SMRT) sequencing technologies were combined to investigate the molecular mechanisms of sesquiterpenoid biosynthesis in A. lancea. A total of 42 differentially expressed genes (DEGs) for terpenoid biosynthesis were identified in the two chemotype groups, and nine full-length terpene synthase (TPS) genes were identified. Subcellular localization revealed that AlTPS1 and AlTPS2 proteins were localized in the nucleus and endoplasmic reticulum. They use FPP as a substrate to generate sesquiterpenoids. AlTPS1 catalyzes biosynthesis of elemol while AlTPS2 is observed to perform β-farnesene synthase activity. This study provides information for understanding the differences in the accumulation of terpenoids in two chemotypes of A. lancea and lays a foundation for further elucidation of the molecular mechanism of sesquiterpenoid biosynthesis.