Dan Zhang,Yun-ling Gao,Sheng Jiang,Yiwen Chen,Yi Zhang,Zheng Pan
Lamiophlomis rotata (L. rotata) is a Tibetan medicinal herb used for centuries that contains iridoid glycosides (IGs), which are pharmacologically active ingredients and can be used for quality control. The IG profiles of the underground and aerial parts of the plant were determined by UPLC-TOF-MS to evaluate the similarity and variability of the different herbal parts listed in the Chinese Pharmacopoeia. Twenty-six IGs were detected in the total ion current (TIC) profile of L. rotata, and twenty-two of these were identified by comparing the retention times and mass spectra of the compounds to those of authentic standards. Among these compounds, five IGs with the same molecular formula (C17H26O11) were identified for the first time by mass spectrometry based on their different hydroxyl group-substituted positions. The aerial part has a similar chemical profile to that of the roots. The difference between the two parts was determined by multivariate statistical analysis of the UPLC-TOF-MS data of 24 specimens. Sesamoside was explored as the most characteristic marker to distinguish the two parts of L. rotata. To further estimate the distinction between the two parts, the content of total IGs and the antioxidant capacity were investigated in samples from different locations. The aerial parts showed a high content of total IGs and high antioxidant capacity, although not higher than those of the roots. The results also suggest the dosage should be increased when the aerial parts are used as crude medicinal materials instead of the underground parts.
This study aimed at obtaining precise quality control standards to efficiently screen Chrysanthemum morifolium Ramat. ‘ Boju ’ with strong xanthine oxidase (XO) inhibitory activity for developing C. morifolium ‘ Boju ’ extract based-hypouricemic functional food. The results indicated significant differences in volatile and phenolic profiles and XO inhibitory (XOI) activities of 31 batches of C. morifolium ‘ Boju ’ collected in herb/tea market. The minority of C. morifolium ‘ Boju ’ having abundant characteristic monoterpenoids and flavonoid aglycones showed strong XOI activities, while the majority of C. morifolium ‘ Boju ’ possessing few corresponding monoterpenoids and flavonoid aglycones exhibited moderate XOI activities. Seven XOI activity-directly related phenolics and ten XOI activity-indirectly related volatiles were identified by UPLC-ESI-QTOF/MS-based and HS-SPME-GC/MS-based spectrum-effect relationships, respectively. Three flavonoids (luteolin, apigenin and acacetin) identified as key XO inhibitors and four monoterpenoids (filifolone, α-terpineol, thymol and piperitenone) closely related to key XO inhibitors were screened for XOI activity-oriented quality control of C. morifolium ‘ Boju ’.
Lard imparts unique organoleptic properties that underpin its essential role in Chinese gastronomy; however, the specific lipid precursors contributing to its aroma remain unclear. This study explores the flavor formation mechanism of lard by comparing its texture and aroma at two preparation temperatures, 130 °C and 100 °C. We identified a total of 256 and 253 lipids at these temperatures, respectively, with triacylglycerols (TGs) and diacylglycerols (DGs) being the predominant lipid species. An HS-GC-IMS analysis detected 67 volatile compounds, predominantly aldehydes, acids, and alcohols. A subsequent Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) identified 49 discriminatory lipids and 20 differential volatiles. A correlation analysis showed a positive relationship between aldehydes and unsaturated triglycerides in lard, with TG (16:1-16:1-18:0), TG (17:2-18:1-18:1), TG (16:1-17:1-18:1), and TG (18:1-18:1-20:1) identified as characteristic markers at both temperatures. Furthermore, there was a positive correlation between ketones and alcohols and phospholipids and sphingolipids containing unsaturated fatty acid chains. TGs and glycerophospholipids (GPs), rich in polyunsaturated fatty acids, are likely key precursors driving the formation of distinct flavors during lard processing. This study elucidates the mechanistic interactions between lipids and volatile organic compounds, providing a framework for optimizing lard processing protocols and flavor modulation.