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Euphorbia tirucalli (Euphorbiaceae) is a species widely utilized for popular medicine in northeast of Brazil because of its innumerable reported medicinal properties. The HPLC-Qtrap-MS/MS analysis from E. tirucalli roots ethanol extract revealed that this species presents 8 flavonoids and 5 shikimate derivative compounds. Chemical studies of these ethanolic extract using chromatographic procedures allowed the isolation of four previously unreported compounds for this species: myricetin, 3,3'-dimethoxy-4-O-α-rhamnopyranoside-ellagic acid, 4-O-methyl-gallic acid and ampelopsin. All structures were determined using 1D and 2D NMR spectroscopy analysis. The ethanol extract and four isolated compounds were evaluated for antimicrobial activity against Staphylococcus aureus, Escherichia coli, Sporothrix brasiliensis and Candida albicans. All the analyzed compounds presented activity against all evaluated bacteria and fungi, with MIC values ranging from 8 to 2048 μg/mL.

The multiple free radical scavenging reactions of flavonoids have been studied considering the gas, benzene, and water phases by applying density functional theory (DFT). Intramolecular hydrogen-bonds are found in all the most stable geometries of flavonoids and can reduce the antioxidant activity of hydroxyl groups, acting as hydrogen-bond donors (5−OH, 3−OH and 3’−OH), while enhancing the antioxidant activity of hydroxyl groups, acting as hydrogen-bond acceptors (4’−OH). In the gas and benzene phases, all of the flavonoids first prefer performing continuous di-hydrogen atom transfer (HAT) reaction from the B ring OH groups to trap two free radicals with the formation of stable quinones for ampelopsin, taxifolin, dihydro orobol and eriodictyol and benzodioxole for hesperetin. They would trap the third free radical via the HAT in the gas phase. In the benzene phase, ampelopsin also favours to apply HAT to trap the third free radical, and the other flavonoids would use the sequential proton loss electron transfer (SPLET) mechanism. In the water phase, the investigated flavonoids would first perform consecutive proton loss (PL) reactions from all of the OH groups with the formation of polyanions. The multiple PL reactions begin from the 7−OH group. The second PL reaction prefers performing in the OH groups on the B benzene ring due to the better delocalization of the negative charge via conjugation over the entire skeleton. The polyanions of the investigated flavonoids scavenge three free radicals via three consecutive ET reactions.

Ampelopsin (APS) is the main bioactive component from Ampelopsis grossedentata and has anti-inflammatory properties. We hypothesize that it could reduce the acute phase response (APR) and help to maintain balance between inflammation-mediated oxidative damage and APS-induced protective mechanisms in liver. In the present study, APS possessed strong DPPH, ABTS, H2O2 and O 2 radical scavenging activities in different in vitro antioxidant assays. Further study demonstrated that APS alleviated APR as reflected in the changes in the whole body metabolic rate, physical conditions, and production of cytokines in LPS-treated piglets. Moreover, APS has the potential to prevent Akt-mediated activation of NF-κB and decreased the levels of STAT3 in inflammation. The administration of APS ameliorated mitochondrial dysfunction and moderated the involvement of Ref-1 and Nrf2 in the attenuation in LPS-induced APR. The present results suggest that the APS attenuate LPS induced inflammation and oxidative stress in liver of piglets.

Increasing evidence suggests that microglia are a major cellular contributor to neuroinflammation. The present study investigated whether Ampelopsin (Amp), a type of flavanonol derivative from Ampelopsis grossedentata, may exert an anti-inflammatory effect on lipopolysaccharide (LPS)-induced BV2 and primary microglia cells. We found that pre-treatment of microglia cells with Amp before LPS with a non-cytotoxic concentration range decreased the production of nitric oxide (NO) and prostaglandin E2 (PGE2). Amp also suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the mRNA and protein levels. In addition, LPS-induced production of pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) was obviously reduced by Amp. Our mechanistic study indicated that Amp suppressed LPS-induced activation of the IκB/NF-κB inflammation pathway without affecting changes in the phosphorylation levels of mitogen-activated protein kinases (MAPKs) in BV2 cells. Further studies revealed that Amp markedly reduced the phosphorylation levels of JAK2-STAT3 and STAT3 nuclear translocation. Overall, our data suggest that Amp can suppress the LPS-induced inflammatory response of microglial cells, indicating that Amp has potential for the treatment of inflammation-mediated neurodegenerative diseases.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. The major component of the plaques, amyloid-β (Aβ), is generated from amyloid-β precursor protein (APP) by β- and γ-secretase-mediated cleavages. Multiple lines of evidence demonstrate that overproduction/accumulation of Aβ in vulnerable brain regions is a primary cause of the pathogenesis of AD. Among the twelve polyphenols isolated from the leaf extracts of Vitis thunbergii var. taiwaniana (VTT), stenophyllol C, stenophyllol B, ampelopsin C, vitisin A, and davidiol A were shown to significantly reduce both Aβ40 and Aβ42 levels in N2a695 cells. Further studies revealed that ampelopsin C and vitisin A reduce Aβ production through inhibiting β-secretase activity, while the effects of the other active polyphenols on reducing Aβ generation are through different mechanisms. These results suggest that VTT extracts may be beneficial for AD prevention and treatment.

Dihydromyricetin (DMY or DHM), also known as ampelopsin, is the main natural flavonol compound extracted from the plant Ampelopsis grossedentata (Hand. -Mazz) W.T. Wang. In recent years, accumulating studies have been conducted to explore the extensive biological functions of DMY, including antitumor, anti-inflammation, organ-protective, and metabolic regulation effects. DMY acts as a potential preventive or therapeutic agent in treating multiple diseases, such as diabetes mellitus, atherosclerosis, nonalcoholic fatty liver disease and osteoporosis. This review article summarizes the preventive and therapeutic potential of DMY in multiple metabolic diseases and the main signaling pathways in which DMY participates to offer a comprehensive understanding and guidance for future studies.

Ampelopsin (Amp), a natural flavonoid found in the vine tea of Ampelopsis grossedentata, exhibited anti-cancer, anti-oxidant, anti-inflammatory, anti-apoptosis and hepatoprotective properties. The current study instigates the protective effect of Amp on carbon tetrachloride (CCl4)-induced hepatic fibrosis and explores its underlying mechanisms. The results indicated Amp decreased the levels of liver injury markers. Amp inhibited liver fibrosis, as indicated by decreases in hepatic collagen deposition, extracellular matrix (ECM) deposition and α-smooth muscle actin (α-SMA). Amp blocked the activation of hepaticstellate cells (HSCs) by decreasing the expression of collage I, α-SMA, tissue inhibitor of matrix metalloproteinases (TIMPs) 1, transforming growth factor (TGF)-β1, phosphorylated Smad3 (p-Smad3) and increasing the expression of matrix metalloproteinases (MMPs) 9 and SIRT1 in the model of liver fibrosis and cultured HSCs. The sirtuin 1 (SIRT1) specific inhibitor Sirtinol activated the TGF-β1/Smad3 pathway and enhanced ECM accumulation. Attractively, Amp up-regulates the expression of autophagy-related proteins microtubule-associated protein light chain three II (LC3-II) and Beclin-1 in vivo and in vitro. However, depletion of autophagy by specific inhibitor 3-MA obviously abolished the inhibiting effect of Amp on HSC activation and hepatic fibrosis. Conclusively, these results suggest that Amp could decrease CCl4-induced hepatic fibrosis through regulating the SIRT1/TGF-β1/Smad3 and autophagy pathway.

The treatment of the fruit of Hovenia dulcis with the cellulase produced by Bacillus amyloliquefaciens DL-3 for the extraction of reducing sugars increased the release of sugars and decreased the extraction temperature and time. The production of the reducing sugars with the treatment of cellulase was 1.43 times higher than that without cellulase. The cellulase produced by B. amyloliquefaciens DL-3 had three different types of cellulosic activities, which seemed to result in the enhanced extraction of reducing sugars. These reducing sugars were used as the substrate for the sequential production of ethanol and acetic acid. The production of ethanol by Saccharomyces cerevisiae KCCM 11293 from 36.1 g/L reducing sugars was 18.0 g/L for 72 h and the sequential production of acetic acid by Acetobacter pasteurianus KCCM 40117 from 18.0 g/L ethanol was 18.4 g/L for 72 h. The concentration of ampelopsin in the fermentation broth was maintained throughout the sequential productions of ethanol and acetic acid.

Two O-glucosides of resveratrol dimers, ampelopsin F-11b-O-β-glucopyranosides with enantiomeric aglycones [cordifoloside A (1) and cordifoloside B (2)] and an enantiomer of the aglycone [(−)-ampelopsin F] were isolated from the leaves of Shorea cordifolia (Dipterocarpaceae). These structures were identified on the basis of spectroscopic evidence and their absolute configurations were elucidated using circular dichroism data. This is the first report on oligostilbenoids that demonstrates the co-occurrence of diastereomeric O-glucosides with enantiomeric aglycones in this family.

This study investigated the protective effects of ampelopsin on H2O2-induced oxidative injury in porcine kidney epithelial cell line, PK-15; cells were pretreated with medium containing 0, 15, 30, and 60 μg mL−1 ampelopsin, respectively, for 1 h prior to the addition of 100 μmol L−1 H2O2. After 2 h, the cell viability, intracellular superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, cellular malondialdehyde (MDA) content, and DNA strand breakage were determined. Results showed that ampelopsin pretreatment did not modify the SOD and GSH-Px inactivation but significantly decreased MDA production; except for the medium dose (30 μg mL−1), all the tested concentrations of ampelopsin did not significantly inhibit cell viability reduction and gave no influence on DNA damage. The results suggested that all the tested doses of ampelopsin pretreatment before H2O2 addition can protect PK-15 cell from H2O2-induced lipid peroxidation, which might not be mediated by the SOD and GSH-Px responsees. The appropriate dose of ampelopsin pretreatment prevents PK-15 cell from DNA damage and cell viability reduction.

Vitis thunbergii var. taiwaniana is a vitaceous native folk medicinal plant in Taiwan. The root of V. thunbergii var. taiwaniana is used to treat hepatitis and arthritis. Centrifugal partition chromatography (CPC) and Sephadex LH-20 gel filtration column chromatography were successively used to isolate and purify three oligostilbenes, (−)-vitisin B, (+)-vitisin A, and ampelopsin A, from the root of V. thunbergii var. taiwaniana. The two-phase solvent system of CPC composed of chloroform–methanol–water (6:7:4, v/v/v) was used for the preparative separation of the methanolic extract of V. thunbergii var. taiwaniana. Using CPC and Sephadex LH-20 column chromatography, about 1 g of the crude extract was separated, yielding 28.9 mg of (−)-vitisin B, 18.7 mg of (+)-vitisin A, and 18.2 mg of ampelopsin A at respective purities of 93%, 91%, and 90%.

Salix sachalinensis has two chemotypes: one biosynthesises ampelopsin as a major component of low molecular weight phenolics in their leaves (A-type), and the other biosynthesises b-D-glucopyranose-1-trans-p-coumarate (PG1) and b-D-glucopyranose-1trans-cinnamate (PG2) in addition to ampelopsin (AP-type). We investigated phenotypic and genetic variations and clonal repeatabilities of the pubescence density, leaf mass per area (LMA), and concentrations of total phenolics, condensed tannin, ampelopsin, PG1 and PG2. Leaves of wild A-type trees contained significantly higher concentrations of total phenolics and ampelopsin, and lower concentration of condensed tannin than those of wild AP-type trees. In the greenhouse experiment that compared leaf traits between cloned trees obtained from wild chemotypes, there were significant between-type variations in the leaf phenolic concentrations, pubescence density, and LMA. Since chemotypes of cloned trees in the greenhouse were the same as those of wild parent trees, chemotype can be considered as a genetically controlled property. There were also significant within-chemotype variations in the pubescence density, LMA, total phenolics, ampelopsin, PG1, and PG2 concentrations, but not in concentration of condensed tannin for either chemotypes. Genetic variation of leaf traits except for LMA in AP-type was significant. PG1 and

Five resveratrol tetramers, amurensins I–M, were isolated from the roots of Vitis amurensis (Rupr.), together with five known resveratrol tetramers, (+)-hopeaphenol, isohopeaphenol, vitisin A, (+)-vitisifuran A, and heyneanol A. Their structures and stereochemistry were determined by chemical and spectroscopic methods, especially by use of 2D NMR analysis. Some of them had an ampelopsin A or a balanocarpol unit, in which the conformations of the seven-membered carbon ring were described for the first time. The anti-inflammatory activities of the tetramers were also tested. Among them, (+)-hopeaphenol, isohopeaphenol, vitisin A, (+)-vitisifuran A and heyneanol A showed potent inhibition on the biosynthesis of leukotriene B 4 (LTB 4 ), and amurensins I and L showed strong antagonism of the histamine acceptor.

The methanol extract of the roots of Ampelopsis brevipedunculata var. hancei exhibited marked protective activity against carbon tetrachloride and d -galactosamine-induced liver damage in primary cultured rat hepatocytes. The extract was fractionated by monitoring the activity to give active fractions from which four novel oxidative oligostilbenes, ampelopsins D, E, H and cis-ampelopsin E, were isolated in addition to the known compounds, (-)-epicatechin, pallidol, miyabenol C, piceid, cis-piceid and resveratroloside. The structures of the new stilbene derivatives have been established on the basis of spectroscopic evidence and chemical reactions. Among them, ampelopsin E and cis-ampelopsin E showed antihepatotoxic activity.

From the stem wood of Parthenocissus tricuspidata, four stilbene derivatives were isolated. Three known structures were characterized as resveratrol, e-viniferin and pallidol, and a new resveratrol dimer was confirmed to be a stereochemical isomer of ampelopsin F, isoampelopsin F, by spectroscopic analysis including 2D NMR.

A novel tetrastilbene, heyneanol A, was isolated from stems of Vitis heyneana together with the previously known ampelopsin C, ampelopsin A and (+)-e-viniferin. Its complex polycyclic structure was elucidated by 1D and 2D NMR analyses.

The 7- O -β-glucopyranoside of ampelopsin (5,7,3′,4′,5′-pentahydroxydihydroflavonol), a novel dihydroflavonol, together with the 7- O -β-glucopyranosides of taxifolin (5,7,3′,4′-tetrahydroxydihydroflavonol) and aromadendrin 5,7,4′-trihydroxydihydroflavonol have been isolated from needles of Norway spruce ( Picea abies ). The structures were established on the basis of acid hydrolysis, TLC and spectral data (UV, 1 H and 13 C NMR).

Two novel distilbenes, betulifol A and betulifol B, were isolated from stems of Vitis betulifolia together with the previously known resveratrol, (+)- e -viniferin; ampelopsin A; ampelopsin C; heyneanol A; hopeaphenol and vitisin A. Their structures were elucidated by 1D and 2D NMR analyses.