Inhibitory effect of Lonicera japonica flos on Streptococcus mutans biofilm and mechanism exploration through metabolomic and transcriptomic analyses.

Introduction: Streptococcus mutans was the primary pathogenic organism responsible for dental caries. Lonicera japonica flos (LJF) is a traditional herb in Asia and Europe and consumed as a tea beverage for thousands of years. Methods: The inhibitory effect and mechanism of LJF on biofilm formation by S. mutans was investigated. The active extracts of LJF were validated for their inhibitory activity by examining changes in surface properties such as adherence, hydrophobicity, auto-aggregation abilities, and exopolysaccharides (EPS) production, including water-soluble glucan and water-insoluble glucan. Results and discussion: LJF primarily inhibited biofilm formation through the reduction of EPS production, resulting in alterations in cell surface characteristics and growth retardation in biofilm formation cycles. Integrated transcriptomic and untargeted metabolomics analyses revealed that EPS production was modulated through two-component systems (TCS), quorum sensing (QS), and phosphotransferase system (PTS) pathways under LJF stress conditions. The sensing histidine kinase VicK was identified as an important target protein, as LJF caused its dysregulated expression and blocked the sensing of autoinducer II (AI-2). This led to the inhibition of response regulator transcriptional factors, down-regulated glycosyltransferase (Gtf) activity, and decreased production of water-insoluble glucans (WIG) and water-soluble glucans (WSG). This is the first exploration of the inhibitory effect and mechanism of LJF on S. mutans, providing a theoretical basis for the application of LJF in functional food, oral health care, and related areas.

Analysis of phenotype formation mechanism of a new variety of Lonicera japonica Flos "Huajin 6" at long bud stage / 药学学报

Based on the long bud stage phenotype of a new Lonicera japonica Flos variety "Huajin 6", using "Huajin 6" and "Da Mao Hua" as materials, probing the mechanism of its phenotype formation. Detection of endogenous Jasmonic acid hormones (JAs) content; the genes related to jasmonic acid (JA) synthesis were identified by transcriptome analysis of Lonicera japonica; flower buds and flowers of "Huajin 6" and "Da Mao Hua" were collected at different periods, and the qRT-PCR (quantitative real-time PCR) technique was used to analyze the trend of the expression of synthesis-related enzyme genes in Lonicera japonica Flos during the bud stage. The study found that the content of JAs in "Huajin 6" Lonicera japonica Flos was significantly lower than that in "Da Mao Hua"; applying exogenous methyl-jasmonate (MeJA) to "Huajin 6" can restore its flowering phenotype, making it close to wild type Lonicera japonica Flos; there are significant differences in the expression of two allene oxide synthase genes (AOS), three lipoxygenase genes (LOX), and two allene oxide cyclase genes (AOC) in the flowers and buds of "Huajin 6" and "Da Mao Hua" at different periods. It is hypothesized that the low expression of JA synthesis-related enzyme genes in " Huajin 6" leads to the blockage of JA synthesis, which causes the formation of the long bud phenotype. This study laid a certain foundation for the genetic breeding of Lonicera japonica, provided a new idea for the improvement of Lonicera japonica varieties, and provided a reference for the study of JAs in plant flower organs.

Discovery of the covalent SARS-CoV-2 Mpro inhibitors from antiviral herbs via integrating target-based high-throughput screening and chemoproteomic approaches.

The main proteases (Mpro ) are highly conserved cysteine-rich proteins that can be covalently modified by numerous natural and synthetic compounds. Herein, we constructed an integrative approach to efficiently discover covalent inhibitors of Mpro from complex herbal matrices. This work begins with biological screening of 60 clinically used antiviral herbal medicines, among which Lonicera japonica Flos (LJF) demonstrated the strongest anti-Mpro effect (IC50 = 37.82 µg/mL). Mass spectrometry (MS)-based chemical analysis and chemoproteomic profiling revealed that LJF extract contains at least 50 constituents, of which 22 exhibited the capability to covalently modify Mpro . We subsequently verified the anti-Mpro effects of these covalent binders. Gallic acid and quercetin were found to potently inhibit severe acute respiratory syndrome coronavirus 2 Mpro in dose- and time- dependent manners, with the IC50 values below 10 µM. The inactivation kinetics, binding affinity and binding mode of gallic acid and quercetin were further characterized by fluorescence resonance energy transfer, surface plasmon resonance, and covalent docking simulations. Overall, this study established a practical approach for efficiently discovering the covalent inhibitors of Mpro from herbal medicines by integrating target-based high-throughput screening and MS-based assays, which would greatly facilitate the discovery of key antiviral constituents from medicinal plants.

Investigation of Lonicera japonica Flos against Nonalcoholic Fatty Liver Disease Using Network Integration and Experimental Validation.

Background and objective: Lonicera japonica Flos (LJF) is a well-known traditional herbal medicine that has been used as an anti-inflammatory, antibacterial, antiviral, and antipyretic agent. The potent anti-inflammatory and other ethnopharmacological uses of LJF make it a potential medicine for the treatment of nonalcoholic fatty liver disease (NAFLD). This research is to explore the mechanisms involved in the activity of LJF against NAFLD using network integration and experimental pharmacology. Materials and methods: The possible targets of LJF involved in its activity against NAFLD were predicted by matching the targets of the active components in LJF with those targets involved in NAFLD. The analysis of the enrichment of GO functional annotations and KEGG pathways using Metascape, followed by constructing the network of active components-targets-pathways using Cytoscape, were carried out to predict the targets. Molecular docking studies were performed to further support the involvement of these targets in the activity of LJF against NAFLD. The shortlisted targets were confirmed via in vitro studies in an NAFLD cell model. Results: A total of 17 active components in LJF and 29 targets related to NAFLD were predicted by network pharmacology. Molecular docking studies of the main components and the key targets showed that isochlorogenic acid B can stably bind to TNF-α and CASP3. In vitro studies have shown that LJF down-regulated the TNF-α and CASP3 expression in an NAFLD cell model. Conclusions: These results provide scientific evidence for further investigations into the role of LJF in the treatment of NAFLD.

The metabolic profile elucidation of Lonicera japonica flos water extract and the metabolic characteristics evaluation of bioactive compounds in human gastrointestinal tract in vitro.

Lonicera japonica Flos (LJF) is taken orally as a health food and medicinal plant in China for a long time. The gastrointestinal metabolism of LJF was investigated in vitro by three independent models (gastric juice, intestinal juice, and human intestinal bacteria), qualitative analyzed by UPLC-LTQ-Orbitrap-MSn and quantified by HPLC-DAD. 72 prototype compounds were detected in LJF water extraction (LJF-WE), including 14 organic acids, 43 iridoids, 14 flavonoids and one other compound. The prototype and metabolic components of LJF-WE bio-transformed by simulated gastric fluid (70 and 12), intestinal fluid (69 and 12) and human fecal bacteria (29 and 70) were characterized, respectively. The metabolites were formed through desaccharization, isomerization, hydrogenation, methylation, dehydration, and then cyclization, glucuronization and dimethylation followed. 8 bioactive compounds including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, sweroside, secoxyloganin, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C were much stable in simulated gastric fluid and intestinal fluid, compared with human fecal bacteria. Especially, sweroside and secoxyloganin with glucoside bonds degradated extraordinarily fast, because of the abundant ß-glucosidases in human fecal bacteria.

[Research progress on pesticide residues of Lonicera Japonica Flos].

Lonicera Japonica Flos is the dried bud or nascent flower of Lonicera japonica(Caprifoliaceae). The plant suffers from various diseases and pests in the growth period and thus pesticides are often used. As a result, the resultant pesticide residues in Lonicera Japonica Flos have aroused great concern. This review summarized the investigation, detection methods, content analysis, and risk assessment of pesticide residues in Lonicera Japonica Flos since 1996, and compared the maximum residue limits among different countries and regions. The results showed that the pesticide residues were detected in Lonicera Japonica Flos from different production areas, and only some exceeded the limits. The residual pesticides have changed from organochlorines to new types such as tebuconazole and nitenpyram. The detection method has upgraded from chromatography to chromatography-mass spectrometry. Most pesticide residues will not cause health risks, except carbofuran. Pesticide residues limit the development of Lonicera Japonica Flos industry in China. In practice, we should improve the drug registration of Lonicera Japonica Flos, promote ecological prevention and control technology, and formulate and promote pesticide residue limit standard of Lonicera Japonica Flos.

Research progress on pesticide residues of Lonicera Japonica Flos / 中国中药杂志

Lonicera Japonica Flos is the dried bud or nascent flower of Lonicera japonica(Caprifoliaceae). The plant suffers from various diseases and pests in the growth period and thus pesticides are often used. As a result, the resultant pesticide residues in Lonicera Japonica Flos have aroused great concern. This review summarized the investigation, detection methods, content analysis, and risk assessment of pesticide residues in Lonicera Japonica Flos since 1996, and compared the maximum residue limits among different countries and regions. The results showed that the pesticide residues were detected in Lonicera Japonica Flos from different production areas, and only some exceeded the limits. The residual pesticides have changed from organochlorines to new types such as tebuconazole and nitenpyram. The detection method has upgraded from chromatography to chromatography-mass spectrometry. Most pesticide residues will not cause health risks, except carbofuran. Pesticide residues limit the development of Lonicera Japonica Flos industry in China. In practice, we should improve the drug registration of Lonicera Japonica Flos, promote ecological prevention and control technology, and formulate and promote pesticide residue limit standard of Lonicera Japonica Flos.

Comparison of the Trace Elements and Active Components of Lonicera japonica flos and Lonicera flos Using ICP-MS and HPLC-PDA.

Thirteen trace elements and active constituents of 40 batches of Lonicera japonica flos and Lonicera flos were comparatively studied using inductively coupled plasma mass-spectrometry (ICP-MS) and high-performance liquid chromatography-photodiode array (HPLC-PDA). The trace elements were 24Mg, 52Cr, 55Mn, 57Fe, 60Ni, 63Cu, 66Zn, 75As, 82Se, 98Mo, 114Cd, 202Hg, and 208Pb, and the active compounds were chlorogenic acid, 3,5-O-dicaffeoylquinc acid, 4,5-O-dicaffeoylquinc acid, luteolin-7-O-glucoside, and 4-O-caffeoylquinic acid. The data of 18 variables were statistically processed using principal component analysis (PCA) and discriminate analysis (DA) to classify L. japonica flos and L. flos. The validated method was developed to divide the 40 samples into two groups based on the PCA in terms of 18 variables. Furthermore, the species of Lonicera was better discriminated by using DA with 12 variables. These results suggest that the method and statistical analysis of the contents of trace elements and chemical components can classify the L. japonica flos and L. flos using 12 variables, such as 3,5-O-dicaffeoylquincacid, luteolin-7-O-glucoside, Cd, Mn, Hg, Pb, Ni, 4-O-caffeoyl-quinic acid, 4,5-O-dicaffeoylquinc acid, Fe, Mg, and Cr.

HPLC fingerprint identification of Lonicera Japonica Flos and Lonicera Flos / 中草药

Objective: To compare the differences between Lonicera Japonica Flos and Lonicera Flos by establishing HPLC fingerprint and calculating the similarity. Methods: The columns was Phenomenex Luna 5 μm C18 (2) 100 A, 250 mm×4.6 mm; The column temperature was 40℃. The mobile phase was acetonitrile-0.5% phosphoric acid, the flow rate was 1 mL/min, and the wavelength was 350 nm. Results: HPLC fingerprint of Lonicera Japonica and similarity evaluation by screening large peak integration were established. The similarity of 12 batches of Lonicera Japonica Flos were all above 0.95, and four batches of Lonicera Flos were less than 0.80. Conclusion: HPLC fingerprint profiles under 350 nm can reflex the differences between Lonicera Japonica Flos and Lonicera Flos effectively; Similarity evaluation by screening large peak integration shows the tiny differences of chemical component.

[Research progress on pharmacological effects and their differences among the flowers, stems and leaves of Lonicera japonica].

It's a common phenomenon that two kinds or more than two kinds of herbs belong to different parts of the same plant. Lonicera Japonica Flos, Lonicera Japonica Caulis and Lonicera Japonica Folium are the typical representative of this phenomenon. They belong to different parts of the Lonicera japonica Thunb. This paper reviewed the research progress on pharmacological effects and their differences among them. It was found that the research mainly concentrated on Lonicera Japonica Flos, and the others were ignored. However, some pharmacological effects in leaves are stronger than that of flowers and stems, such as antibacterial, anti-bird flu and antioxidant activity.Lonicera Japonica Flos is mainly used for the treatment of respiratory tract virus infection while Lonicera Japonica Caulis is mainly used for the treatment of hepatitis virus infection, respectively. Finally, main problems and suggestions on pharmacological effects among them were also discussed.

Research progress on pharmacological effects and their differences among the flowers, stems and leaves of Lonicera japonica / 中国中药杂志

It's a common phenomenon that two kinds or more than two kinds of herbs belong to different parts of the same plant. Lonicera Japonica Flos, Lonicera Japonica Caulis and Lonicera Japonica Folium are the typical representative of this phenomenon. They belong to different parts of the Lonicera japonica Thunb. This paper reviewed the research progress on pharmacological effects and their differences among them. It was found that the research mainly concentrated on Lonicera Japonica Flos, and the others were ignored. However, some pharmacological effects in leaves are stronger than that of flowers and stems, such as antibacterial, anti-bird flu and antioxidant activity.Lonicera Japonica Flos is mainly used for the treatment of respiratory tract virus infection while Lonicera Japonica Caulis is mainly used for the treatment of hepatitis virus infection, respectively. Finally, main problems and suggestions on pharmacological effects among them were also discussed.

Identification of Lonicerae japonicae flos Volatile Oils by Fourier-transform Infrared Spectroscopy / 中国中医药信息杂志

Objective To set up a method for identification of Lonicerae japonicae flos volatile oils using Fourier-transform infrared spectroscopy. Methods The volatile oils of Lonicerae japonicae flos and Lonicerae flos was extracted by steam distillation combined with continuous liquid-liquid extraction with hexane. An oil film was prepared for Fourier-transform infrared spectroscopy scanning by dropping the volatile oils solution on the KBr disc and evaporating the solvent. The obtained infrared spectrum was treated by baseline removing and median filter smoothing. The spectral data within 1800-850 cm-1 was selected as the characteristic spectrum for hierarchical cluster analysis. And the volatile oils of Lonicerae japonicae flos and Lonicerae flos were discriminated by the result of hierarchical cluster analysis. Results Enough volatile oils were extracted for obtaining Fourier-transform infrared spectrum from small amount of Lonicerae japonicae flos. The method developed in the study was able to discriminate Lonicerae japonicae flos volatile oils from Lonicerae flos volatile oils. Conclusion The method can be used for identification of Lonicerae japonicae flos volatile oils.