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Comprehensive Summary: Twenty‐two new limonoids, mufolinoids A—V (1—22), including six rings A, B‐seco limonoids (1—6), twelve ring A‐seco limonoids (7—18), four ring‐intact limonoids (19—22), together with thirteen known compounds (23—35) were isolated from Munronia unifoliolata. Their structures including absolute configurations were elucidated by combination of NMR, HR‐MS, single‐crystal X‐ray diffraction and calculations of ECD and NMR technologies. Compounds 24, 25, 33, 34 could be significantly reversed the multidrug resistance of MCF‐7/doxorubicin (DOX) cells, and the reversal fold (RF) was much higher than that of positive drug Verapamil. Compounds 24, 28, and 29 exhibited significant anti‐inflammatory activity with the IC50 values in the range of 17.7—39.4 μmol/L. Furthermore, compound 29 could markedly inhibit the release of IL‐1β by inhibiting the initiation and assembly of NLRP3 inflammasome, which demonstrates the great potential of limonoids as an anti‐inflammatory agent. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Sarcaglarols A—D (1—4), two pairs of lindenane−monoterpene heterodimers fused by a 1,2‐dioxane moiety, were discovered and isolated from the leaves of Sarcandra glabra guided by MS/MS molecular networking‐based strategy. Their planar structures, absolute configurations of basic skeleton and flexible polyhydric side chain were established by analysis of HRESIMS, NMR spectroscopic data, ECD spectrum, and the X‐ray diffraction study of isopropylidene derivatives. An intermolecular [2+2+2] cycloaddition may play a key role in the biosynthesis pathway of the 1,2‐dioxane moiety fused lindenane−monoterpene heterodimer skeleton, which can be recognized as the biogenetic precursors of our previous reported lindenane−normonoterpene conjugates. In addition, compounds 1, 3 and 4 exhibited moderate inhibitory effects of lipid accumulation in free fatty acid‐exposed L02 cells. [ABSTRACT FROM AUTHOR]

• Comprehensive molecular networking strategy was proposed to improve the annotation accuracy of natural products. • MOlNetEnhancer workflow analysis for automatic compounds classification in herbal medicine. • Chemotaxonomic chromatogram was built to achieve component visualization. • MS/MS of 48 purified compounds from Ginkgo biloba leaf were collected and shared to public library. [Display omitted] Molecular networking (MN) is an efficient tool for natural product research. However, single MN might lead to false annotation due to the limited information, and the importance of combining MN with chromatogram is always ignored. In this study, we proposed a comprehensive MN strategy combining feature-based molecular networking (FBMN) and dual ionization mode MS/MS to improve the annotation accuracy and to achieve structural feature visualization in a chemotaxonomic chromatogram. Three steps were taken: (1) employing FBMN and dual ionization mode MS/MS to distinguish isomers and improve components' identification accuracy. (2) Using a 3-level initiative supported by in-house database to evaluate the annotation confidence. As a result, 95 compounds were successfully identified from Ginkgo biloba leaf extract (GBE) and Ginkgo biloba leaf (GBL), and 70 compounds mainly consisting of flavonoid glycosides, ginkgolides, and lignan glycosides were assigned as high-confidence molecules. (3) Building color-dependent chemotaxonomic chromatograms, to achieve component visualization by connecting FBMN with chromatogram in which the peaks of the same color indicated the compounds with similar structural features. Our research provided a new and efficient strategy for component identification and visualization of herbal medicine. [ABSTRACT FROM AUTHOR]