Evaluation of Total Flavonoids, Myricetin, and Quercetin from Hovenia dulcis Thunb. As Inhibitors of α-Amylase and α-Glucosidase.

This study was designed to investigate the inhibition effect and mechanism of total flavonoids, myricetin and quercetin extracted from Hovenia dulcis Thunb. on α-amylase and α-glucosidase in order to explore the potential use of Hovenia flavonoids in alleviating postprandial hyperglycemia. The results demonstrate that total flavonoids, myricetin, and quercetin were effective inhibitors of α-amylase with IC50 values of 32.8, 662 and 770 µg ml-1, respectively. And all three were effective inhibitors of α-glucosidase with IC50 values of 8, 3 and 32 µg ml-1, respectively. Enzyme kinetics tests and Lineweaver-Burk results showed the inhibition effects of total flavonoids, myricetin and quercrtin on α-amylase were all reversible and competitive, and the effects on α-glucosidase were all reversible but non-competitive. This study revealed that Hovenia flavonoids, especially myricetin, are effective and promising functional foods in alleviating type 2 diabetes mellitus.

A review on extraction, purification, structural characteristics, biological activities, applications of polysaccharides from Hovenia dulcis Thunb. (Guai Zao).

Hovenia dulcis Thunb. (H. dulcis) is a widely distributed plant with a long history of cultivation and consumption. As a common plant, it has economic, edible and medicinal value. H. dulcis polysaccharides are one of their main bioactive ingredients and have many health benefits, such as anti-diabetes, antioxidation, anti-glycosylation, anti-fatigue, immune regulation activities and alcoholic liver disease protection activity. In this paper, the research progress of H. dulcis polysaccharides in extraction, purification, structural characteristics, biological activities, existing and potential applications were reviewed, which could provide new valuable insights for future studies.

Hovendulcisic acid A-D: four novel ceanothane-type triterpenoids from Hovenia dulcis stems with anticancer properties.

Sixteen ceanothane-type triterpenoids, including four new compounds-hovendulcisic acids A-D (1-4) -were purified from the stems of Hovenia dulcis Thunb. The structures of 1-4 were confirmed by comprehensive means including ECD and quantum chemical calculations. Putative biosynthetic pathways of 1-16 were proposed, and 3, 5, and 15 exhibited antitumor activity on A549 and MDA-MB-231 cells.

Hovenia dulcis Thunb. Fruit Extract Attenuates Psoriatic Skin Inflammation in Tumor Necrosis Factor-α-Stimulated Human Keratinocyte HaCaT Cells In Vitro.

Hovenia dulcis Thunb. fruit (HDF) is traditionally used for treating liver diseases and alcohol poisoning. The purpose of this study was to explore the effects of HDF on hyperproliferation, levels of inflammatory cytokines, and signaling mechanisms in human psoriatic keratinocyte HaCaT cells. HDF showed a preventive effect on tumor necrosis factor-α (TNF-α)-induced abnormal proliferation of psoriatic keratinocytes. Furthermore, real-time reverse transcription-PCR analysis showed that HDF suppressed the expressions of inflammatory cytokines; interleukin (IL)-1α and IL-1ß and chemokines; CCL-20 and CXCL-8 in TNF-α-induced HaCaT cells. Western blotting revealed that HDF suppressed the levels of phosphorylated IκB and STAT3 together with a decline in the levels of phosphorylated mitogen-activated protein kinases (MAPKs). These outcomes indicate that HDF prevents the abnormal proliferation of keratinocytes and modulates inflammatory responses by suppressing nuclear factor-κB (NF-κB) and STAT3 activation through downregulation of the MAPK signaling pathway in TNF-α-induced psoriatic keratinocytes. Our study demonstrates that HDF is prospective and beneficial for psoriatic skin inflammation.

Three new bisflavonols from the seeds of Hovenia dulcis Thunb. and their anti-RSV activities.

Three novel bisflavonol derivatives, Hovenianins A-C, along with 12 known flavonoids were isolated and identified from the seeds of Hovenia dulcis Thunb. Their structures were established on the basis of spectroscopic methods (MS, UV, IR, 1D and 2D NMR) and electronic circular dichroism experiments. Hovenianin A (1) was the first dimer of flavonol linked dihydroflavonol via the B rings at C-2' and C-2″'positions to be found in nature. While Hovenianins BC (2-3) were a pair of diastereoisomeric bis-dihydroflavonols firstly reported in the Hovenia genus. The in vitro antiviral activity against respiratory syncytium virus (RSV) were evaluated by cytopathic effect (CPE) reduction assay. As a result, compounds 4, 5, and 10 displayed better antiviral effect against RSV A2 strains.

Laxative Activity of the Hot-Water Extract Mixture of Hovenia dulcis Thunb. and Phyllostachys pubescens Mazel in Chronic Constipation Model SD Rats.

This study examined the laxative effects of hot-water extracts of Hovenia dulcis Thunb. (HD), Phyllostachys pubescens Mazel (PM), and a 2:8 mixture of both (HP) in two chronic constipation models. For the loperamide-induced constipation model, animals were divided into an untreated group, negative control group (loperamide 4 mg/kg), positive control group (bisacodyl 4 mg/kg) group, and six treatment groups (HP 100 or 400, HD 50 or 100, and PM 100 or 400 mg/kg). For the lowfiber diet-induced constipation model, animals were divided into an untreated group (normal diet), negative control group (low-fiber diet), positive control group (Agio granule, 620 mg/kg), and the same treatment groups. Fecal number, weight, fecal water content, and intestinal transit ratio were higher in the groups treated with HP, HD, and PM than in the groups treated with loperamide or lowfiber diet. Thickness of colon mucosa and muscle layers were increased in the treated groups. Colon tension increased in the HP groups, and [Ca2+]i measurements using fura-2 as an indicator showed that HP inhibits ATP-mediated Ca2+ influx in IEC-18 cells. These results showed that the HP mixture has laxative activity by increased mucin secretion and inducing contractile activity and relaxation. It may be a useful therapeutic strategy for ameliorating in chronic constipation.

Anti-steatotic and anti-inflammatory effects of Hovenia dulcis Thunb. extracts in chronic alcohol-fed rats.

The anti-steatotic and anti-inflammatory effects of fruit water extract (FW) and seed ethanol extract (SE) of Hovenia dulcis Thunb. in chronic alcohol-fed rats were investigated. Rats were fed a liquid diet containing 36% calories from alcohol and orally administered FW or SE (300 and 500mg/kg/day). Both FW and SE reduced hepatic lipid contents and droplets, serum lipid concentration and inflammatory markers (hs-CRP, TNF-α and IL-6) levels compared with the alcohol control group. Alcohol led to significant decreases in the hepatic fatty acid oxidative gene (Ppargc1a, Cpt1a and Acsl1) levels, while it significantly increased the Myd88 and Tnfa gene levels. However, FW or SE supplementation significantly up-regulated gene expression of Ppargc1a, Ppara, Cpt1a and Acsl1, and down-regulated gene expression of Myd88, Tnfa and Crp compared with the alcohol control group. FW or SE supplementation also significantly decreased hepatic activities of fatty acid synthase and phosphatidate phosphohydrolase in chronic alcohol-fed rats. Plasma alcohol and acetaldehyde levels, hepatic enzyme activity and protein expression of CYP2E1 were lowered by FW or SE supplementation. These results indicate that both FW and SE play an important role in improvement of alcoholic hepatic steatosis and inflammation via regulation of lipid and inflammation metabolism.

A standardized extract of the fruit of Hovenia dulcis alleviated alcohol-induced hangover in healthy subjects with heterozygous ALDH2: A randomized, controlled, crossover trial.

ETHNOPHARMACOLOGICAL RELEVANCE: Hovenia dulcis, known as the oriental raisin tree, is mainly found in East Asia. It has long been used as traditional folk remedies for alcohol intoxication. AIM OF THE STUDY: To examine the anti-hangover effect of Hovenia dulcis Thunb. fruit extract (HDE) in a randomized controlled crossover trial. MATERIALS AND METHODS: Twenty-six eligible male adults with heterozygous ALDH2 (23.7±0.3 years old) consumed 360mL of Korean Soju (50g alcohol) together with HDE (2460mg) or matched placebo with subsequent crossover. The blood samples were taken at baseline and 1, 4, and 12h post-treatment. RESULTS: Blood alcohol, acetaldehyde, and total hangover scores were highest at 1h post-treatment with no difference between groups, but declines in hangover symptom scores were significant in the HDE group compared to the placebo group. Significant differences between groups were also observed on interleukin (IL)-6, IL-10, IL-10/IL-6 ratio, and aspartate aminotransferase levels, but not on endotoxins. Pearson correlation analysis revealed a positive correlation between total hangover symptom scores and IL-6 and IL-10 level. Further analyses by CYP2E1 polymorphism at rs10776687, rs2031920, rs3813867, and rs4838767 alleles showed a reversed association, suggesting that CYP2E1 polymorphism might be an effect modifier. CONCLUSIONS: The results suggest that a favorable effect of HDE on alcohol hangovers might be associated with enhancing homeostatic regulation of inflammatory response. The magnitude of impact might be different in the presence of CYP2E1 polymorphism.

Anti-alcoholism effects of Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture on acute alcoholism mice / 药学实践杂志

Objective To study the anti-alcoholism effect of Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture on acute alcohol poisoning in mice.Methods A model of acute alcoholism in mice was established by intragastrical administration of alcohol.The best ratio of each component in the mixture was identified by observing the sobering effect of the mixtures on mice.The best ratio mixture was divided into low dose group and high dose group.The mice tolerance time, drunken time, the ethanol concentration in the blood and the alcohol dehydrogenase activity in liver were measured to study the anti-alcoholism effect of the mixture.Results The Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture not only increased the tolerance time and decreased the drunken time of mice, but also significantly reduced the ethanol concentration in blood and improved the activity of alcohol dehydrogenase in liver.Conclusion This study found that Puerariae lobatae radix, Puerariae lobatae flowers, Hovenia dulcis thunb mixture has anti-alcoholism effect on acute alcoholism in mice.

The nootropic components of Hovenia dulcis / 第二军医大学学报

Objective: To investigate the nootropic components of Hovenia dulcis. Methods: Six saponins were isolated from Hovenia dulcis and Step-down test was used to examine the memory ability of mice. The escape latency and the times of wrong performance within 3 min were used to evaluate the memory ability of mice. To study the effects of saponins on learning and memory in mice, we divided the mice into 6 groups: youth group, aged group, aged plus piracetam(0.3 g/kg) group, aged plus saponins (0.6 g/kg) group, aged plus saponins (0.3 g/kg) group, and aged plus saponins(0.15 g/kg) group. To study the influence of saponins on impairment of memory acquirement, consolidation, and reoccurrence (induced by scopolamine, sodium nitrite and 40% ethanol, respectively), mice were also divided into the following 7 groups: control group, untreated group, Piracetam group (0.3 g/kg), compound 3 group(0.3 g/kg), compound 4 group(0.3 g/kg), compound 5 group(0.3 g/kg), and compound 6 group (0.3 g/kg). Results: The chemical structures of six saponins were elucidated as 3-O-stigmasterol-(6-O- palmitoyl)-β-D-glucopyranoside (1), β-daucosterin (2), hovenidulcioside A1 (3), hoduloside I (4), hoduloside IV (5), and saponins C2 (6). Among them, compounds 1 and 2 were isolated from this plant for the first time. Compounds 5 and 6 had enhancing effect on the learning and memory ability of natural senile mice, and they could improve the impairment of memory acquirement, consolidation and recurrence in mice induced by scopolamine, sodium nitrite and 40% ethanol, respectively. Conclusion: The aglycone of jujubogenin might be the main saponins contributing to the nootropic effect of total saponins from Hovenia dulcis.

Study on the Bioavtive Fraction of the Seeds of Hovenia Dulcis Thunb.for Acute Alcoholism / 中国药房

OBJECTIVE:To study the active fraction of the seeds of Hovenia Dulcis Thunb.to treat acute alcoholism.METHODES:The seeds of Hovenia Dulcis Thunb.were divided into five parts:superitical fluid extraction(SFE)part,chloroform extraction part,ethyl acetate extraction part,n-butanol extraction part and water extraction part.The effects of the active fraction of the seeds of Hovenia Dulcis Thunb.on ebriety latency,ebriety rate,mortality,and ethanol concentration-time curve of the alcoholism mice were investigated.RESULTS:The ethyl acetate extract could prolong the ebriety latency of the mice,decrease ebriety rate and mortality of the alcoholism mice,and significantly decrease serum ethanol concentrations at 0.5,1,and 1.5h after alcohol administration(P

Study on Quality Standard of Hovenia dulcis Thunb Extract / 中国中医药信息杂志

Objective To establish a quality standard of Hovenia dulics Thunb. Method The presence of quercetin was identified and assayed by TLC and HPLC, respectively. Result Linearity of marker was obtained over the range of 1.32 ～ 5.28 ?g (r =0.9999). The average recovery rate was 98.78% (RSD=1.08%). Conclusion TLC is specific. The method of quality is accurate, reappearance, simple, rapid, and suitable for the quality control of Hovenia dulcis Thunb.

The nootropic components of Hovenia dulcis / 第二军医大学学报

Objective:To investigate the nootropic components of Hovenia dulcis.Methods: Six saponins were isolated from Hovenia dulcis and Step-down test was used to examine the memory ability of mice.The escape latency and the times of wrong performance within 3 min were used to evaluate the memory ability of mice.To study the effects of saponins on learning and memory in mice,we divided the mice into 6 groups:youth group,aged group,aged plus piracetam(0.3 g/kg) group,aged plus saponins(0.6 g/kg) group,aged plus saponins(0.3 g/kg) group,and aged plus saponins(0.15 g/kg) group.To study the influence of saponins on impairment of memory acquirement,consolidation,and reoccurrence(induced by scopolamine,sodium nitrite and 40% ethanol,respectively),mice were also divided into the following 7 groups:control group,untreated group,piracetam group(0.3 g/kg),compound 3 group(0.3 g/kg),compound 4 group(0.3 g/kg),compound 5 group(0.3 g/kg),and compound 6 group(0.3 g/kg).Results: The chemical structures of six saponins were elucidated as 3-O-stigmasterol-(6-O-palmitoyl)-?-D-glucopyranoside(1),?-daucosterin(2),hovenidulcioside A1(3),hoduloside Ⅰ(4),hoduloside Ⅳ(5),and saponins C2(6).Among them,compounds 1 and 2 were isolated from this plant for the first time.Compounds 5 and 6 had enhancing effect on the learning and memory ability of natural senile mice,and they could improve the impairment of memory acquirement,consolidation and recurrence in mice induced by scopolamine,sodium nitrite and 40% ethanol,respectively.Conclusion: The aglycone of jujubogenin might be the main saponins contributing to the nootropic effect of total saponins from Hovenia dulcis.