Transcriptomic and metabolomic analyses provide insights into the biosynthesis of chlorogenic acids in Lonicera macranthoides Hand.-Mazz

Lonicera macranthoides Hand.-Mazz (L. macranthoides) is a medicinal herb that is widely distributed in South China. The developmental stage and corolla dehiscence of the flower are the important factors affecting the quality of medicinal ingredients. However, neither the regulatory mechanism controlling chlorogenic acids biosynthesis in L. macranthoides nor the molecular basis of effect of corolla dehiscence on the quality of medicinal materials is fully understood. In this study, metabolomics and transcriptomics were used to analyze the metabolic and transcriptional differences of two different cultivars closed bud type (Bt), and flowering type (Ft), as well as the effect of jasmonic acid methyl ester (MeJA) on chlorogenic acids (CGAs) biosynthesis. In total, large number of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were filtered among three lines of samples. Gene metabolite correlation analyses revealed a ‘core set’ of 30 genes and 54 genes that were strongly correlated with CGAs biosynthesis and regulating the flowering, respectively. Quantitative real-time polymerase chain reaction results proved the alterations in the expression levels of genes encoding the pathways involved in CGAs biosynthesis. The ion abundances of CGAs were most significantly increased, while some of the CGAs derived and Caffeoyl-CoA-derived substances showed the most largely reduced abundances in the closed bud type (Bt) compared to the flowering type (Ft). MeJA may leads to the activation of downstream genes in CGAs biosynthesis pathway. Overall, there were significant differences in the transcriptional and metabolic levels of CGAs biosynthesis pathway in flower buds of different flowering cultivars. The redirection of metabolic flux may contribute to increased accumulation of CGAs. However, whether MeJA and flowering have direct effects on the accumulation of CGAs needs further studied. These researches effectively expanded the functional genomic library and provide new insights into CGAs biosynthesis in L. macranthoides.

Chemical Composition and Antibacterial Activity of the Essential Oil Isolated From Flos Lonicerae (Flower Buds of Lonicera macranthoides Hand.-Mazz.)

Flos Lonicerae (FL, flower buds of Lonicera macranthoides Hand.-Mazz.) is a traditional Chinese medicinal herb that is officially listed in the Chinese Pharmacopoeia. The aim of this study was to screen the chemical composition and to study the antibacterial activity of essential oils of Flos Lonicerae. The chemical composition of the essential oils was investigated using gas chromatography-mass spectrometry (GC-MS). The antibacterial activity was evaluated by the disc diffusion method to determine minimum inhibitory concentration (MIC). The major compounds of Flos Lonicerae essential oils were linalool (10.4%), palmitic acid (8.0%), geraniol (6.9%), hexanal (2.5%), and α-terpineol (2.2%). Flos Lonicerae essential oils demonstrated antibacterial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The results of this study suggest that the essential oils of Flos Lonicerae have an interesting antimicrobial effect and may be a new potential source for a natural antimicrobial applied in the pharmaceutical field.

Determination of effective medicinal components in Lonicera macranthoides flower buds

This study is to determination of active medicinal components in Lonicera macranthoides. The results of High-performance liquid chromatography showed that the contents of chlorogenic acid were as follows: Baiyun: 6.297%, jincuilei: 5.293%, yincuilei: 5.288%, common variety: 7.455%, common variety (after flowering): 4.140%. The contents of Luteolin in different Lonicera macranthoides varieties were as follows: Baiyun: 0.0264%; Jincuilei: 0.0573%; Yincuilei: 0.0347%; common variety: 0.0394%; common variety (after flowering) : 0.0197%.

Metabolomics Reveals Distinct Metabolites between Lonicera japonica and Lonicera macranthoides Based on GC-MS

Lonicera japonica Thunb. (LJ) and Lonicera macranthoides Hand. -Mazz. (LM) have been widely used in Chinese medicine for thousands of years. Although the morphological characteristics of LJ and LM are quite similar, there are significant distinctions of medicinal ingredients (mainly the secondary metabolites) and clinical indications between them. However, the in-depth differences of primary metabolites have not thoroughly been studied yet. Therefore, gas chromatography-mass spectrometry- (GC-MS-) based metabolomics method combined with chemometric methods were performed to analyze the distinction in this study. The results showed that LJ and LM were obviously classified into two groups. 10 metabolites were obtained as biomarkers on account of their p values, pcorr values, and differing variable importance in projection (VIP) values. Metabolic pathway analysis showed that the galactose metabolism and starch and sucrose metabolism gathered as potential pathways caused these extraordinary differences of primary metabolites between LJ and LM. Further, we found that the differences of main medicinal ingredients between LJ and LM could be interpreted from these metabolites according to the analysis of mainly related pathways. The metabolites involved in the starch and sucrose metabolism presented upregulated in LJ, while almost all metabolites in the galactose metabolism, the TCA cycle, and the phenolic acid part of phenylpropanoid metabolism were downregulated in LJ. Therefore, the energy stored in the starch and sucrose metabolism may be saved to produce flavonoid, which could be the reason that the level of flavonoid of phenylpropanoid metabolism is higher in LJ compared to LM. Consequently, this study presented an effective tool for quality evaluation of LJ and LM and laid a foundation for further studies of the metabolic mechanisms and high-quality manufacturing of them.

Prenyleudesmanes and A Hexanorlanostane from the Roots of Lonicera macranthoides

Three previously undescribed compounds, two prenyleudesmanes (1 and 2), and one hexanorlanostane (3), were isolated from the roots of Lonicera macranthoides. Their structures were established based on 1D and 2D nuclear magnetic resonance (NMR) spectra and high-resolution electrospray ionization mass spectral (HR-ESI-MS) data. The absolute configurations of 1 and 3 were determined by X-ray diffraction. To the best of our knowledge, this is the first time that the absolute configuration of a prenyleudesmane with a trans-decalin system and a hexanorlanostane have been unambiguously confirmed by single-crystal X-ray diffraction with Cu Kα radiation. Thecompounds were tested for their antiproliferative activity on the cancer cell lines (HepG2 and HeLa). The compounds 1–3 exhibited moderate inhibitory effects against two human cancer cell lines.