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Staphylococcus aureus is the main culprit, causing a variety of severe clinical infections. At the same time, clinics are also facing the severe situation of antibiotic resistance. Therefore, effective strategies to address this problem may include expanding the antimicrobial spectrum by exploring alternative sources of drugs or delaying the development of antibiotic resistance through combination therapy so that existing antibiotics can continue to be used. Plumbagin (PLU) is a phytochemical that exhibits antibacterial activity. In the present study, we investigated the in vitro antibacterial activity of PLU. We selected five antibiotics with different mechanisms and inhibitory activities against S. aureus to explore their interaction with the combination of PLU. The interaction of combinations was evaluated by the Bliss independent model and visualized through response surface analysis. PLU exhibited potent antibacterial activity, with half maximal inhibitory concentration (IC50) and minimum inhibitory concentration (MIC) values against S. aureus of 1.73 μg/mL and 4 μg/mL, respectively. Synergism was observed when PLU was combined with nitrofurantoin (NIT), ciprofloxacin (CPR), mecillinam (MEC), and chloramphenicol (CHL). The indifference of the trimethoprim (TMP)-PLU pairing was demonstrated across the entire dose-response matrix, but significant synergy was observed within a specific dose region. In addition, no antagonistic interactions were indicated. Overall, PLU is not only a promising antimicrobial agent but also has the potential to enhance the growth-inhibitory activity of some antibiotics against S. aureus, and the use of the interaction landscape, along with the dose-response matrix, for analyzing and quantifying combination results represents an improved approach to comprehending antibacterial combinations.

Perilla frutescens was an annual herb considered as one of the “One Root of Medicine and Food”, and it was used widely for food and medical treatment. Its main active ingredients were volatile organic compounds (VOCs), but it was easily affected during drying and storage. The leaves, seeds and stems had shown differences in therapeutic effects, but the underlying reason remained unclear. In the present work, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC–MS) were utilized to effectively and comprehensively analyze VOCs of fresh and dried P. frutescens between the leaves, stems and seeds. Meanwhile, chemometric analysis was applied to compare and identify characteristic volatile markers. As a result, 60 VOCs were identified by HS-GC-IMS and 115 VOCs were identified by HS-SPME-GC–MS from P. frutescen. 25 potential volatile markers were selected based on a combination model of orthogonal partial least squares discriminant analysis (OPLS-DA) and random forest (RF). The models could be used to analyze the variation between fresh and dried P. frutescens and distinguish the differences in different parts effectively and comprehensively. It was the first research regarding the method development of HS-GC-IMS and HS-SPME-GC–MS that comprehensively analyzes the VOCs characterization of fresh and dried P. frutescens in different parts and the findings obtained would evaluate the quality and provide a reference for further exploration of the edible and medicinal effects of P. frutescens.

The flower buds of three Panax species (PGF: P. ginseng; PQF: P. quinquefolius; PNF: P. notoginseng) widely consumed as health tea are easily confused in market circulation. We aimed to develop a green, fast, and easy analysis strategy to distinguish PGF, PQF, and PNF. In this work, fast gas chromatography electronic nose (fast GC e-nose), headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were utilized to comprehensively analyze the volatile organic components (VOCs) of three flowers. Meanwhile, a principal component analysis (PCA) and heatmap were applied to distinguish the VOCs identified in PGF, PQF, and PNF. A random forest (RF) analysis was used to screen key factors affecting the discrimination. As a result, 39, 68, and 78 VOCs were identified in three flowers using fast GC e-nose, HS-GC-IMS, and HS-SPME-GC-MS. Nine VOCs were selected as potential chemical markers based on a model of RF for distinguishing these three species. Conclusively, a complete VOC analysis strategy was created to provide a methodological reference for the rapid, simple, and environmentally friendly detection and identification of food products (tea, oil, honey, etc.) and herbs with flavor characteristics and to provide a basis for further specification of their quality and base sources.

This work was designed to investigate the dynamic changes process of non-volatile organic compounds (n-VOCs) and volatile organic compounds (VOCs) in mulberries during different growth periods using UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS, and HS-GC-IMS. A total of 166 compounds were identified, including 68 n-VOCs and 98 VOCs. Furthermore, principal component analysis (PCA), random forest analysis (RFA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze differences in mulberries at different ripening stages. A total of 74 compounds appeared or disappeared at different ripening periods and 24 compounds were presented throughout the growth process. Quantitative analysis and antioxidant experiments revealed that as the mulberries continued to mature, flavonoids and phenolic acids continued to increase, and the best antioxidant activity occurred from stage IV. Conclusively, an effective strategy was established for analyzing the composition change process during different growth periods, which could assist in achieving dynamic change process analysis and quality control.

Acori tatarinowii rhizome (ATR) is a Traditional Chinese Medicine (TCM), which has multiple effects, such as neuroprotective activity, antidepressant and other activity. However, the widespread cultivation of ATR has led to it varying quality. Therefore, it is important to find a method to quickly identify the components of ATR. Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC–MS) were applied to analyze and characterize the volatile organic compounds (VOCs) of ATR. 33 VOCs were identified by HS-GC-IMS and 95 VOCs were identified by HS-SPME-GC–MS from 15 batches of ATR. Then, quantification of estragole, methyleugenol, γ-asarone, β-asarone and asarone by gas chromatography-mass spectrometry (GC–MS). The fingerprint of HS-GC-IMS and the heatmap of HS-SPME-GC–MS were established. Which compared differential components of ATR. In addition, principal component analysis (PCA) was performed on the results of both instruments. The VOCs in the ATR were significantly correlated with β-asarone and asarone by PatternHunter analysis. It assisted HS-GC-IMS determine ATR quality. It is the first report regarding the method development of HS-GC-IMS and HS-SPME-GC–MS that targets the VOCs characterization of ATR, and the findings obtained would benefit the quality control and distinguish the complex analytical objects of ATR.

Quality evaluation of phytomedicines is limited to small molecules as quality markers, even for herbs with high sugar contents. We established a high-resolution method for distinguishing similar medicinal materials using sugar as quality marker, taking Schisandrae Chinensis Fructus (SCF) and Schisandrae Sphenantherae Fructus (SSF) as an example. High performance liquid chromatography with an evaporative light-scattering detector (HPLC-ELSD), high performance size exclusion chromatography coupled with multi-angle laser light scattering detector and refractive index detector (HPSEC-MALLS-RID) and high performance liquid chromatography with photo-diode array (HPLC-PDA) after 1-phenyl-3-methyl-5-pyrazolone (PMP) pre-column derivatization were used respectively to determine monosaccharide contents, molecular weights and monosaccharide compositions of polysaccharides in this study. The differences of SCF and SSF from ten producing areas were compared by principal component analysis (PCA) and hierarchical cluster analysis (HCA). Results showed that contents of fructose and glucose were similar between SCF and SSF. Molecular weight (Mw) of SCF polysaccharides was ranging from 1.561 × 102 to 6.599 × 102 kDa, and that of SSF polysaccharides was ranging from 8.524 × 102 to 1.7416 × 103 kDa. Schisandra polysaccharides were mainly composed of mannose, galacturonic acid, glucose, galactose and arabinose. Based on PCA and HCA, SCF and SSF from ten different areas were classified into three categories. With great accuracy, sensitivity and stability, the methods established in this study had important reference value for quality evaluation, development and utilization of saccharide components in medicinal materials.

The co-elution, pervasive isomers, and frequently occurring in-source fragmentation definitely hinder the comprehensive characterization of the multiple components from traditional Chinese medicine (TCM) by liquid chromatography/mass spectrometry. Herein, a dimension-enhanced strategy, by utilizing an ion mobility quadrupole time-of-flight mass spectrometer coupled to ultra-high performance liquid chromatography (UHPLC/IM-QTOF-MS) with the ability of offering four-dimensional information (retention time, Rt; drift time or collision cross section, CCS; accurate mass of precursors; and accurate MS2 product ions), is presented. Shuanghe Decoction (SHD) is a classic tonifying formula composed of nine herbs, however, little is known to its chemical complexity, hitherto. Good chromatographic separation was achieved on an HSS T3 column, and by the Vion™ IMS-QTOF high-resolution mass spectrometer, data-independent MSE and High-Definition MSE (HDMSE) in both the negative and positive electrospray ionization modes were employed for acquiring the collision-induced dissociation-MS2 data. A self-built database, including 642 known compounds, was established, which assisted to perform the automated peak annotation by UNIFI™. By reference to 55 compounds, totally 236 components were identified or tentatively characterized from SHD with 4D data recorded. The combination of negative and positive modes could yield more information complementary to structural elucidation. Compared with the conventional MSE, HDMSE exhibit of merits in the provision of CCS, better separation and detection those easily co-eluting components, and reduction of the false positives in the identification results. Conclusively, the combination of HDMSE acquisition, in-house library, and UNIFI-facilitated automated peak annotation, renders a potent approach dedicated to deconvoluting the chemical composition of complex systems like TCM formulae.

The pericarps of Zanthoxylum bungeanum (ZBP) and leaves of Zanthoxylum bungeanum (ZBL) are popular spices in China, and they have pharmacological activities as well. In this experiment, the volatile organic compounds (VOCs) of the pericarps of Zanthoxylum bungeanum in Sichuan (SJ) and its leaves (SJY) and the pericarps of Zanthoxylum bungeanum in Shaanxi (SHJ) and its leaves (SHJY) were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The fingerprint of HS-GC-IMS and the heat maps of HS-SPME-GC-MS were established. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were performed. The results showed that a total of 95 components were identified, 62 components identified by HS-SPME-GC-MS and 40 components identified by HS-GC-IMS, of which 7 were the same. The analysis found that SJ and SHJ were obviously distinguished, while SJY and SHJY were not. There were considerably fewer VOCs in the leaves than in the pericarps. In the characterization of the VOCs of ZBL and ZBP, the flavor of ZBP was more acrid and stronger, while the flavor of ZBL was lighter and slightly acrid. Thirteen and eleven differential markers were identified by HS-GC-IMS and HS-SPME-GC-MS, respectively. This is helpful in distinguishing between SHJ and SJ, which contributes to their quality evaluation.

Gynostemma pentaphyllum (thumb.) Makino is a functional herbal tea commonly used in Asian countries and regions to reduce blood lipid levels. G. pentaphyllum saponin is the main component, but there are still a large number of components with lipid-lowering activity that have not been found. In this study, 10 novel dammarane-type saponins, (1–10) and a known one (11) were isolated from G. pentaphyllum. Ten new compounds were identified and named as yunnangypenosides A-J (1–10), and another known one (11) was also obtained. Their chemical structures were determined by MS, NMR spectroscopic analyses. Moreover, the cytotoxicities on human HepG-2 hepatocellular carcinoma cells of these isolates were evaluated, and the results showed that compounds 1–11 had no obvious cytotoxicity. Finally, all these compounds were evaluated for their lipid-lowering effect by means of the oil red O staining method. Ten compounds could significantly reduce lipid levels except of 2, especially 8 exhibite the strongest hypolipidemia activity.

Russula vinosa Lindbl is a wild edible mushroom that is usually used for original material of food and soup and has rich nutritional value. What are the nutritional ingredients? In order to answer this question, we investigated the chemical constituents of this wild functional food. Six new compounds (1–6), together with nine known ones (7–15), were isolated from R. vinosa. The six new compounds were named as vinosane (1), rulepidadione C (2), (24E)-3,4-seco-cucurbita-4,24-diene-26,29-dioic acid-3-methyl ester (3), (24E)-3,4-seco-cucurbita-4,24-diene-26-oic acid-3-ethyl ester (4), (24E)-3β-hydroxycucurbita-5,24-diene-26,29-dioic acid (5), and (2S,3S,4R,2′R)-2-(2′-hydroxydocosanoylamino)eicosane-1,3,4-triol (6). Their structures were determined based on spectroscopic methods including HR-ESI-MS, 1D, and 2D NMR. Moreover, a cell counting kit-8 (CCK-8 kit) was used to screen for the cytotoxicity of compounds 1–5 and 7–13 on mouse macrophage RAW 264.7 cells. The results showed that compounds 1–5 and 7–13 had no obvious cytotoxicity. In addition, the inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells were evaluated. Compounds 1, 3, 4, 7, 12, and 13 showed moderate inhibitory activity on NO production.

An aptamer-based electrochemical biosensor was successfully developed and applied in the rapid detection of pathogenic Escherichia coli (E. coli) in licorice extract. The thiolated capture probes were firstly immobilized on a gold electrode, and then the biotinylated aptamer probes for E. coli were introduced by hybridization with the capture probes. Due to the stronger interaction between the aptamer and the E. coli, a part of the biotinylated aptamers will dissociate from the capture probes in the presence of E. coli. The residual biotinylated aptamer probes can quantitatively bind with streptavidin-alkaline phosphatase. Subsequently, α-naphthyl phosphate substrate was catalytically hydrolyzed to generate electrochemical response, which could be recorded by a differential pulse voltammetry. The dependence of the peak current on the logarithm of E. coli concentration in the range from 5.0 × 102 colony forming units (CFU)/mL to 5.0 × 107 CFU/mL exhibited a linear trend with a detection limit of 80 CFU/mL. The relative standard deviation of 5 successive scans was 5.3%, 4.5% and 1.1% for 5.0 × 102, 5.0 × 105 and 5.0 × 107 CFU/mL E. coli, respectively. In the detection of the licorice extract samples, the results obtained from the proposed strategy and traditional culture counting method were close to each other, but the time consumption was only ~1/30 compared with the traditional method. These results demonstrate that the designed biosensor can be potentially utilized for rapid microbial examination in traditional Chinese medicine and relevant fields.

A novel copolymer was synthesized successfully via polymerization of part (6-O-butene diacid ester)-β-cyclodextrin and styrene. Because the carboxyl groups of the new copolymer possess a strong chelating ability, the copolymer is capable of coordinating with metal ions. Utilizing this new ability, the copolymer metal complexes containing Cu(II) and Ag(I) were synthesized. The structures and properties of the copolymer and its metal complexes were characterized by IR, UV, MS, 13C NMR, X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), electron spin resonance (ESR), and cyclic voltammetry (CV). The results show that the novel copolymer metal complexes were composed of the desired metal ion, polystyrene, and the functionalized β-cyclodextrin (β-CD). Furthermore, they possess stable electrochemical activity and are paramagnetic. [ABSTRACT FROM AUTHOR]