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Five natural secondary metabolites as cinnamic acid (1), (+)-catechin (2), (-)-epicatechin (3), p-coumaric acid (4), and ferulic acid (5) were isolated from Amanita caesarea based on anti-inflammatory activity-guided extraction. Their structures (1-5) were determined by NMR spectra as well as by comparison with previously reported literature. Compounds 3 and 5 have been isolated from A. caesarea for the first time. The anti-inflammatory activity through inhibition of nitric oxide (NO) production of isolates (1-5) was evaluated. Among them, compounds 2 and 3 exhibited strong inhibitory activity with IC50 values of 4.8 and 5.7 μM, respectively. Compounds 4 and 5 with IC50 values of 18.4 and 9.6 μM, respectively showed moderate inhibitory activity. The results proposed that A. caesarea might exert anti-inflammatory effects due to its mainly NO-inhibitory constituents

Three compounds, naringenin (1), arctiin (2) and martinoside (3) were isolated from the whole plant of Scutellaria indica (Labiatae). The chemical structures of these compounds were determined by spectroscopic analyses including 1D- and 2D-NMR. Compounds 2 and 3 were isolated from S. indica for the first time

Natural condensed tannins (CT) have received great interest due to their vast beneficial bioactivities. Recently, Euonymus laxiflorus, an edible medicinal herb collected in the Central Highlands of Vietnam, was newly recognized as a natural source rich in antioxidant CT. The aim of this study is to scale up extraction and investigate various novel bioactivities of the isolated CT. The screening of the parts used rich in CT, such as heartwood, trunk bark, branch, and the leaves of EL, indicated that the EL trunk bark (ELTB) has the highest CT content. E. laxiflorus CT (ELCT) was extracted with high-level scale from ELTB via several techniques and then was qualified by NMR spectra and HPLC finger printing. A condensed tannin ELBT-3.1.d was isolated and showed its high molecular weight of ≥ 10 kDa and various in vitro bioactivities. ELBT-3.1.d demonstrated high antioxidant capacity (IC50 = 6.11 µg/mL), and potent enzymes inhibition targets in anti-diabetes, especially showing novel potential inhibition against human salivary α-amylase with IC50 value of 3.01 µg/mL. ELBT-3.1.d displayed no anti-NO effect but did show moderate to effective anticancer activities against A549, MCF-7, HepG2, and WiDr. Notably, condensed tannin ELBT-3.1.d displayed no toxicity to normal cells and a novel potential prebiotic effect on Lactobacillus paracasei BCRC14023 and Lactobacillus rhamnosus BCRC16000. In the animal test, ELCT demonstrated significant effect on reducing plasma glucose in mice at the doses of 50–100 mg/kg BW. The current study contributes to enrich the novel bioactivities of ELCT which may be suggested as functional food or drugs due to processing numerous beneficial bioactivities.