The Scutellaria baicalensis—Coptis chinensis pair is an herbal combination used for the treatment of various heat-related diseases. During the extraction process, two herbs can mutually influence the extraction efficiency of the chemical constituents contained in each herb. The concentrations of five flavonoids from S. baicalensis and seven alkaloids from C. chinensis were compared in paired or single hot-water extracts at different temperatures (80, 90, and 100 °C) and extraction times (60, 90, and 120 min). Temperature- and time-dependent increases in marker compound concentrations were observed in both paired and single extracts, with the exception of baicalin, berberine, and coptisine in the paired extracts at 100 °C. However, the extractions of the compounds in the paired and single extracts were affected differently by the extraction conditions. Furthermore, the concentrations of most marker compounds in single extracts were 1.09–44.13 times those in paired extracts. The contents of baicalin, wogonoside, coptisine, and berberine, known to be easily aggregated by the flavonoid–alkaloid complex, were changed by 0.024–0.764-fold in the paired extract. The effect of extraction temperature and time on the formation of the flavonoid–alkaloid complex was not significant. The extraction efficiency of the flavonoids and alkaloids can be affected by the pair of S. baicalensis—C. chinensis, which is a primary factor in the chemical modification of two herb-containing herbal extracts.

Spirodela polyrhiza (L.) S_CHLEID. has been used to treat epidemic fever, dysuria, and various skin ailments, such as measles eruptions, eczema, and pruritus, in China, Japan, and Korea. In this study, the active compounds in S. polyrhiza and their target genes were identified by network-based analysis. Moreover, the study evaluated the effects of a 70% ethanolic extract of S. polyrhiza (EESP) on skin lesions, histopathological changes, inflammatory cytokines, and chemokines in mice with contact dermatitis (CD) induced by 1-fluoro-2,4-dinitrobenzene (DNFB), and examined the inhibitory effects of EESP on mitogen-activated protein kinase (MAPK) signalling pathways. In our results, 14 active compounds and 29 CD-related target genes were identified. Among them, tumour necrosis factor (TNF) and interleukin 6 (IL-6) were identified as hub genes, and luteolin and apigenin showed a strong binding affinity with TNF (<−8 kcal/mol) and IL-6 (<−6 kcal/mol). Our in vivo studies showed that topical EESP ameliorated DNFB-induced skin lesions and histopathological abnormalities, and reduced the levels of TNF-α, interferon (IFN)-ɣ, IL-6, and monocyte chemotactic protein (MCP)-1 in inflamed tissues. In conclusion, our findings suggest the potential for dermatological applications of S. polyrhiza and suggest that its anti-dermatitis action is related to the inhibition of TNF and IL-6 by luteolin and luteolin glycosides.

The genus Angelica comprises various species utilized for diverse medicinal purposes, with differences attributed to the varying levels or types of inherent chemical components in each species. This study employed DNA barcode analysis and HPLC analysis to genetically authenticate and chemically classify eight medicinal Angelica species (n = 106) as well as two non-medicinal species (n = 14) that have been misused. Nucleotide sequence analysis of the nuclear internal transcribed spacer (ITS) region revealed differences ranging from 11 to 117 bp, while psbA-trnH showed variances of 3 to 95 bp, respectively. Phylogenetic analysis grouped all samples except Angelica sinensis into the same cluster, with some counterfeits forming separate clusters. Verification using the NCBI database confirmed the feasibility of species identification. For chemical identification, a robust quantitative HPLC analysis method was developed for 46 marker compounds. Subsequently, two A. reflexa-specific and seven A. biserrata-specific marker compounds were identified, alongside non-specific markers. Moreover, chemometric clustering analysis reflecting differences in chemical content between species revealed that most samples formed distinct clusters according to the plant species. However, some samples formed mixed clusters containing different species. These findings offer crucial insights for the standardization and quality control of medicinal Angelica species.