Opposite trends of glycosides and alkaloids in Dendrobium nobile of different age based on UPLC-Q/TOF-MS combined with multivariate statistical analyses.

INTRODUCTION: Alkaloids and glycosides are the active ingredients of the herb Dendrobium nobile, which is used in traditional Chinese medicine. The pharmacological effects of alkaloids include neuroprotective effects and regulatory effects on glucose and lipid metabolism, while glycosides improve the immune system. The pharmacological activities of the above chemical components are significantly different. In practice, the stems of 3-year-old D. nobile are usually used as the main source of Dendrobii Caulis. However, it has not been reported whether this harvesting time is appropriate. OBJECTIVE: The aim of this study was to compare the chemical characteristics of D. nobile in different growth years (1-3 years). METHODS: In this study, ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q/TOF-MS) was employed to analyze the constituents of D. nobile. The relative abundance of each constituent was analyzed with multivariate statistical analyses to screen the characteristic constituents that contributed to the characterization and classification of D. nobile. Dendrobine, a component of D. nobile that is used for quality control according to the Chinese Pharmacopoeia, was assayed by gas chromatography. RESULTS: As a result, 34 characteristic constituents (VIP > 2) were identified or tentatively identified as alkaloids and glycosides based on MS/MS data. Moreover, the content of alkaloids decreased over time, whereas the content of glycosides showed the opposite trend. The absolute quantification of dendrobine was consistent with the metabolomics results. CONCLUSION: Our findings provide valuable information to optimize the harvest period and a reference for the clinical application of D. nobile.

[Chemical Constituents from Leaves of Acanthus ilicifolius and Their Anti-influenza Virus Activities].

OBJECTIVE: To study the chemical constituents from the leaves of Acanthus ilicifolius. METHODS: The compounds were isolated by silica and gel column chromatographic methods and identified by spectoscopic analysis. The anti-influenza virus activities of these compounds were obtained by measuring the neuraminidase activity of influenza virus. RESULTS: Five compounds were isolated and their structures were identified as blepharin(1), acteoside(2), isoverbascoside(3), daucosterol(4), and 3-O-ß-D-glucopyranosyl-stigmasterol(5). CONCLUSION: All the compounds are isolated from the leaves of Acanthus ilicifolius for the first time, and compounds 1 ~ 3 exhibit the anti-influenza virus activities.

Chemical characterization and comparative analysis of different parts of Cocculus orbiculatus through UHPLC-Q-TOF-MS.

Cocculus orbiculatus (L.) DC. (C. orbiculatus) is a medicinal herb valued for its dried roots with anti-inflammatory, analgesic, diuretic, and other therapeutic properties. Despite its traditional applications, chemical investigations into C. orbiculatus remain limited, focusing predominantly on alkaloids and flavonoids. Furthermore, the therapeutic use of C. orbiculatus predominantly focuses on the roots, leaving the stems, a significant portion of the plant, underutilized. This study employed ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) with in-house and online databases for comprehensive identification of components in various plant parts. Subsequently, untargeted metabolomics was employed to analyze differences in components across different harvest periods and plant sections of C. orbiculatus, aiming to screen for distinct components in different parts of the plant. Finally, metabolomic analysis of the roots and stems, which contribute significantly to the plant's weight, was conducted using chemometrics, including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), and heatmaps. A total of 113 components, including alkaloids, flavonoids, and organic acids, were annotated across the root, stem, leaf, flower, and fruit, along with numerous previously unreported compounds. Metabolomic analyses revealed substantial differences in components between the root and stem compared to the leaf, flower, and fruit during the same harvest period. PLS-DA and OPLS-DA annotated 10 differentiating components (VIP > 1.5, P < 0.05, FC > 2 or FC < 0.67), with 5 unique to the root and stem, exhibiting lower mass spectrometric responses. This study provided the first characterization of 113 chemical constituents in different parts of C. orbiculatus, laying the groundwork for pharmacological research and advocating for the enhanced utilization of its stem.

Identification of Pyrrolizidine Alkaloids in Senecio Plants by Liquid Chromatography-Mass Spectrometry.

Pyrrolizidine alkaloids (PAs) are considered as the major constituents that cause hepatoxicity in Senecio plants. PAs can be found in about 3%-5% of the world's flowering plants. Nowadays, the identification method of PAs by separation and preparation was too slow and lacked effective power. A rapid method to identify PAs in plants must be developed. Based on the fragmentation regularity, the hepatoxic PAs and nonhepatoxic PAs were characterized by liquid chromatography-mass spectrometry (LC-MS). The detailed structures of PAs in five Senecio plants were identified based on tandem mass spectrometry (MS/MS) spectrum and chemical research information. In the present study, some new fragmentation regularities of PAs have been found, such as product ions at m/z 122, m/z 140 and m/z 124, m/z 142, which have been discovered as the characteristic fragments of lactone and mono-esterase type of saturated PAs, respectively. Moreover, two product ions at m/z 120 and m/z 138 have been reported as the characteristic fragments of unsaturated PAs. Some of them were found in Senecio species for the first time, and some of them may be new nature product or even new compound. Finally, we classified these plants into five categories based on PAs which were identified in the present study; the result corresponded with the classification by morphology. In addition, we have found some constituents that have odd molecular weight number only in Senecio species but not in Ligularia species; the detailed structures of these non-PAs constituents need penetrating study. LC-MS was rapid and sensitive method for detecting and identifying PAs in plants. Pyrrolizidine alkaloids were the toxiferous constituent of Senecio plants. In this study, we found that PAs can be used as the characteristic constituent of Senecio species.

Quantitative Determination of 15 Active Components in Lepidium meyenii with UHPLC-PDA and GC-MS.

In this study, a method using ultrahigh-performance liquid chromatography with photodiode array (UHPLC-PDA) was established and validated for the simultaneous quantification of 10 active components, including eight macamides and two glucosinolates, in Lepidium meyenii (maca). A gas chromatographic mass spectroscopy (GC-MS) method was used to determine the levels of three benzyl isothiocyanates and two sterols in maca. Liquid chromatographic separation was achieved on a Waters Acquity UHPLC HSS T3 column (2.1 mm × 100 mm, 1.8 µm) with gradient elution over 15 min. The mobile phase was (B) acetonitrile-(A) 10 mM aqueous ammonium phosphate, and the detection wavelength was 210 nm. The gas chromatographic separation was performed on an SH-Rxi-1 MS column, and the ionization mode was electron ionization (EI). Two methods were confirmed to have desirable precision (RSD < 1.58%), repeatability (RSD < 1.97%), stability (RSD < 1.76%), and good linearity (R 2 ≥ 0.999) within the test range. The recoveries were in the range of 96.79-109.99%, with an RSD below 2.39%. We applied the established methods and successfully analyzed 15 compounds in maca processed under different drying conditions, providing a comprehensive reference for maca processing method of development. In summary, this study provided two rapid and effective methods for the quantification of 15 active components, which contributed to the in-depth maca quality control and provided a reference for the development of maca products.