Binbin Wei

Microcos paniculata L. (ML) is an edible herbal tea plant with regional differences in flavor and bioactive quality. However, the chemical and microbial factors associated with these differences remain unclear. This study integrated HS-GC-Orbitrap-MS/MS, 16S rRNA sequencing, sensory evaluation, color analysis, and antioxidant assays to characterize ML samples from Guangdong, Guangxi, and Yunnan, China. Guangdong samples were characterized by the highest total phenolic and flavonoid contents and superior antioxidant capacity, whereas Yunnan samples showed the best sensory performance, particularly for aroma and taste attributes. A total of 133 volatile constituents were tentatively identified, mainly comprising olefins and cycloolefins, aromatic compounds, terpenes, alcohols, and ketones. Chemometric analysis revealed clear origin-dependent separation and identified 12 differential volatile compounds, including p-cymene, L-limonene, α-phellandrene, dimethyl sulfide, and ethylbenzene. Bacterial community analysis showed distinct origin-associated patterns, and several bacterial taxa were correlated with characteristic volatile compounds and quality traits. Functional prediction and multivariate correlation analysis suggested potential associations among environmental factors, bacterial communities, volatile metabolites, and antioxidant properties. These findings provide a foodomics-based framework for understanding geographical quality variation in ML and offer potential markers for origin traceability and quality evaluation of edible herbal tea resources.

Maydis stigma is an important medicine herb used in many parts of the world for treatment of diabetes mellitus, which main bioactive ingredients are flavonoids. This paper describes for the first time a study on the comparative pharmacokinetics of six active flavonoid ingredients of Maydis stigma in normal and diabetic rats orally administrated with the decoction. Therefore, an efficient and sensitive ultra high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of six anti-diabetic ingredients (cynaroside, quercetin, luteolin, isorhamnetin, rutin and formononetin) of Maydis stigma in rat plasma has been developed and validated in plasma samples, which showed good linearity over a wide concentration range (r² > 0.99), and gave a lower limit of quantification of 1.0 ng·mL⁻¹ for the analytes. The intra- and interday assay variability was less than 15% for all analytes. The mean extraction recoveries and matrix effect of analytes and IS from rats plasma were all more than 85.0%. The stability results showed the measured concentration for six analytes at three QC levels deviated within 15.0%. The results indicated that significant differences in the pharmacokinetic parameters of the analytes were observed between the two groups of animals, whereby the absorptions of these analytes in the diabetic group were all significantly higher than those in the normal group, which provides an experimental basis for the role of Maydis stigma in anti-diabetic treatment.