In Vitro Antibacterial Activity and Synergistic Antibiotic Effects of Phlorotannins Isolated from Eisenia bicyclis Against Methicillin‐Resistant Staphylococcus aureus

Six phlorotannins, isolated from Eisenia bicyclis, were evaluated for antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentrations (MIC) of the compounds were in the range 32 to 64 µg/mL. Phlorofucofuroeckol‐A (PFF) exhibited the highest anti‐MRSA activity, with an MIC of 32 µg/mL. An investigation of the interaction between these compounds and the β‐lactam antibiotics ampicillin, penicillin, and oxacillin revealed synergistic action against MRSA in combination with compound PFF. To our knowledge, this is the first report on the anti‐MRSA activity of phlorotannins from E. bicyclis. The results obtained in this study suggest that the compounds derived from E. bicyclis can be a good source of natural antibacterial agents against MRSA. Copyright © 2012 John Wiley & Sons, Ltd.     

Lapacho Tea (Tabebuia impetiginosa) Extract Inhibits Pancreatic Lipase and Delays Postprandial Triglyceride Increase in Rats

Earlier work in our laboratory indicated that ethanolic extracts of Tabebuia impetiginosa, Arctium lappa L., Calendula officinalis, Helianthus annuus, Linum usitatissimum and L. propolis, inhibit pancreatic lipase in vitro. In a follow‐up study we assessed their effects on plasma triglycerides in rats fed on a fatty meal. Extracts, orlistat or only ethanol were given orally to the rats together with the test meal and the rate of increase of postprandial triglycerides was assessed over 4 h. Clearing of the triglycerides from the blood compartment was abolished by inhibiting lipoprotein lipase with Triton WR‐1339. Our results showed that out of all the extracts, the bark of Tabebuia impetiginosa led to a significant delay in the postprandial increase of plasma triglycerides. However, lapachol, which is contained in the bark of Tabebuia impetiginosa and soluble in ethanol, had no lipase inhibitory effect in vitro and hence this substance did not seem to mediate the pertinent effect. Copyright © 2012 John Wiley & Sons, Ltd.     

Lipase inhibitory activity in alcohol extracts of worldwide occurring plants and propolis

In the search for lipase inhibitory agents, 144 alcohol plant extracts and propolis were screened for pancreatic lipase activity in vitro using methods with methylresorufin and triolein as substrates. Ethanol extracts of Linum usitatissimum (oil flax) and Helianthus annuus (sunflower seeds) showed the strongest lipase inhibitory actions with ID₅₀ values of 1:370 and 1:166, respectively. Copyright © 2008 John Wiley & Sons, Ltd.     

侧柏叶不同提取部位抑制胰脂肪酶及抗氧化活性筛选

目的:考察侧柏叶不同提取部位体外抑制胰脂肪酶活性和抗氧化活性。方法:对侧柏叶的醇提液、石油醚部位、乙酸乙酯部位、正丁醇部位、水部位采用体外抑制胰脂肪酶活性研究,并通过其清除1,1二苯基苦基苯肼(DPPH)自由基和Fe3+还原能力(FRAP)测定侧柏叶提取物的体外抗氧化作用。结果:侧柏叶提取物均有不同程度抑制胰脂肪酶活性,以乙酸乙酯部位效果最佳(IC50为26.09 mg·L-1),其次正丁醇部位(IC50为39.02 mg·L-1)和醇提物(IC50为98.20 mg·L-1),石油醚部位(IC50为188.27 mg·L-1)和水部位(IC50为325.28 mg·L-1)最弱。抗氧化活性依次为醇提液(DPPH IC50为7.59 mg·L-1,FRAP 4.40 mmol·g-1)乙酸乙酯部位(DPPH IC50为8.28 mg·L-1,FRAP 3.82 mmol·g-1)正丁醇部位(DPPH IC50为24.21mg·L-1,FRAP 1.77 mmol·g-1)水部位(DPPH IC50为27.53 mg·L-1,FRAP 1.38 mmol·g-1)石油醚部位。结论:初步确定侧柏叶抑制胰脂肪酶活性有效成分主要在乙酸乙酯与正丁醇部位,抗氧化及其相关成分主要在乙酸乙酯部位。     

基于分子对接技术探讨中药抑制人胰脂肪酶活性的潜在物质基础以及用药规律研究

目的 探讨中药抑制人胰脂肪酶(Human pancreatic lipase,HPL)活性的潜在物质基础以及用药规律.方法 以OB(oral bioavailability)≥30％、DL(drug likeness)≥0.18、Lipinski类药五原则及Verb原则为条件从TCMSP数据库中筛选出化合物并构建配体数...     

Tyrosinase Inhibitory Activity of Total Triterpenes and Poricoic Acid A Isolated from Poria cocos

Objective With the improvement of people’s living standards, people’s requests for beauty are increasing. Skin whitening and lightening have become the pursuit of many women, and whitening and removing freckles have become the focus of scientific research. At present, widely used whitening agents, such as kojic acid, vitamin C, and its derivatives, have shortcomings such as poor stability and retarded effect. Therefore, safer and more effective whitening products from herbs are urgently needed. To explore the possibility of triterpenes as whitening active substance, the effects of total triterpenes of Poria (TTP) and poricoic acid A (PAA) on mushroom tyrosinase activities and B16 cells were investigated, and their mechanisms on mushroom tyrosinase were also studied. Methods Using arbutin and nicotinamide as reference substances, we determinated the inhibitory effects of TTP and PAA on mushroom tyrosinase and tyrosinase in B16 cells and then studied the inhibitory mechanism on mushroom tyrosinase. Results TTP and PAA exhibited good inhibitory effects on the activities of monophenolase and diphenolase in mushroom tyrosinase, as well as a certain inhibitory effect on tyrosinase in B16 cells. Conclusion TTP and PAA are potential whitening active ingredients.     

Medicinal Plants Traditionally Used for Treatment of Obesity and Diabetes Mellitus – Screening for Pancreatic Lipase and α‐Amylase Inhibition

In order to find new pancreatic lipase (PL) and α‐amylase inhibitors from natural sources for the treatment of obesity and related diseases as diabetes mellitus II, 23 medicinal plants with weight‐reducing, serum glucose‐reducing or related potential were investigated. Methanolic and water extracts of the plants were evaluated by using two in vitro test systems. Our findings have shown that the methanolic extract of Hibiscus sabdariffa L. (Malvaceae) showed high inhibitory activities to PL (IC₅₀: 35.8 ± 0.8 µg/mL) and α‐amylase (IC₅₀: 29.3 ± 0.5 µg/mL). Furthermore, the methanolic extract of Tamarindus indica L. (Leguminosae) showed a high anti‐lipase (IC₅₀: 152.0 ± 7.0 µg/mL) and the aqueous extract a high anti‐amylase (IC₅₀: 139.4 ± 9.0 µg/mL) activity. This work provides a priority list of interesting plants for further study with respect to the treatment of obesity and associated diseases. Copyright © 2015 John Wiley & Sons, Ltd.     

Inhibitory Effects of Key Compounds Isolated from Corni fructus on BACE1 Activity

Progressive cerebral deposition of Aβ in the brain is a seminal event in the pathogenesis of Alzheimer's disease (AD). Aβ is generated from the amyloid precursor protein (APP) by proteolytic processing of β‐secretase (BACE1) and γ‐secretase. Consequently, BACE1, a key enzyme in the production of Aβ, is a prime target for therapeutic intervention in AD. In the course of screening for natural BACE1 inhibitors from Corni fructus, the ethyl acetate (EtOAc) fraction showed significant inhibitory activity against BACE1. By activity guided purification, three compounds of BACE1 inhibitors p‐coumaric acid, gallic acid and ursolic acid were isolated from Corni fructus EtOAc fraction. All isolated compounds suppressed BACE1 in a dose dependent manner. p‐Coumaric acid, in particular, exhibited significant inhibitory activity against BACE1 with 9.0 × 10^‐5 m and a K_i value of 1.9 × 10^‐6 m . Also this compound was non‐competitive with a substrate in the Dixon plot, suggesting that it might bind either to the β‐secretase subsite or to another regulatory site. All compounds showed no significant attenuation of TACE (α‐secretase) and other serine proteases such as chymotrypsin and trypsin, demonstrating that they were relatively selective and specific inhibitors of BACE1. These novel findings suggest that Corni fructus contains biologically active components that may be used to attenuate the progression and/or prevention of Alzheimer's disease. Copyright © 2012 John Wiley & Sons, Ltd.     

Inhibitory activities of pancreatic lipase and phosphodiesterase from Korean medicinal plant extracts

To find new pancreatic lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) inhibitors from natural products, 61 medicinal plants from Korea were screened for their antilipase activity for prevention of obesity. Dried and powdered plants were extracted three times with EtOH and extracts were obtained by removal of the solvent in vacuo. Lipase activity was determined by measuring the hydrolysis of p-nitrophenyl butyrate to p-nitrophenol. Also, the inhibitory effect was measured on phosphodiesterase (PDE), another therapeutic target for obesity. Of the extracts tested, Sorbus commixta (stem, leaf) and Viscum album (whole plant) exhibited antilipase activity (with IC(50) values of 29.6 μg/mL and 33.3 μg/mL, respectively) and only anti-PDE activity (IC(50) values of 20.08 μg/mL and 35.15 μg/mL, respectively).     

抑制乙酰胆碱酯酶活性的蛇足石杉内生真菌筛选

目的筛选具有乙酰胆碱酯酶抑制活性的蛇足石杉内生真菌菌株。方法采用DTNB显色法,优化条件后筛选;对蛇足石杉的29株内生真菌菌株发酵液醇提物进行了酶抑制活性的初步筛选。结果xg,g8,g5,xgc2,xy7对乙酰胆碱酯酶具有较高的抑制率,其IC50分别是285.62,293.53,434.17,668.82,856.21μg/ml。结论蛇足石杉内生真菌xg,g8,g5发酵醇提物能够较为显著地抑制乙酰胆碱酯酶,为寻找具有乙酰胆碱酯酶抑制作用的药用资源开辟了一条新的途径。     

Effects of Cyanidin‐3‐O‐glucoside on Synthetic and Metabolic Activity of Ethanol Stimulated Human Pancreatic Stellate Cells

Activated pancreatic stellate cells (PSC) play a major role in the development of chronic pancreatitis. Flavonoids (C‐3‐O‐G) theoretically may have potential to suppress activated PSC. The aim of our study was to determine the ability of C‐3‐O‐G to invert synthetic and metabolic activity of alcohol stimulated human pancreatic stellate cells (hPSC). In the present study we demonstrate that treatment with C‐3‐O‐G decreased proliferation rate of ethanol activated hPSC by 51%. Synthesis of extracellular matrix proteins in activated hPSC was markedly inhibited, as shown by reduced levels of collagen I and fibronectin expression. The decrease of secretion of fibronectin by 33% and in collagen I‐25% in ethanol activated and C‐3‐O‐G treated hPSC was observed. Moreover, treatment of ethanol activated hPSC with C‐3‐O‐G resulted in the decrease of oxygen consumption rate by 44% and reduced levels of ATP synthesis (i.e. energy production) by 41%. Hence, the effects of C‐3‐O‐G on ethanol activated hPSC may provide new insights for the use of anthocyanins as anti‐fibrogenic agents in treatment and/or prevention of pancreatic fibrosis. Copyright © 2015 John Wiley & Sons, Ltd.     

Inhibitory Effect of Verbascoside Isolated from Buddleja brasiliensis Jacq. ex Spreng on Prolyl Oligopeptidase Activity

The phenylpropanoid glycoside verbascoside [2‐(3,4‐dihydroxyphenylethyl)‐1‐O‐α‐l ‐rhamnopyranosyl‐(1→3)‐β‐d ‐(4‐O‐caffeyl)‐glucopyranoside] (1) has been isolated as the main constituent of the crude extract of Buddleja brasiliensis Jacq. ex Spreng from Southern Brazil. The crude extract, main fractions and the compound 1 were evaluated for inhibition of the enzymes acetylcholinesterase (AChE), dipeptidyl peptidase‐IV (DPP‐IV) and prolyl oligopeptidase (POP). Compound 1 showed weak activity against DPP‐IV with an IC₅₀ >> 150 µm and was inactive against AChE, with a pMIQ determined by bioautography of 9.6. In contrast, 1 displayed significant inhibition of POP in a dose‐dependent manner with an IC₅₀ value of 1.3 ± 0.2 µm , similar to the positive control, baicalin, with a POP IC₅₀ of 12 ± 3 µm . Copyright © 2012 John Wiley & Sons, Ltd.     

Estrogenic Activity Including Bone Enhancement and Effect on Lipid Profile of Luteolin‐7‐O‐glucoside Isolated from Trifolium alexandrinum L. in Ovariectomized Rats

Luteolin‐7‐O‐glycoside (LG), an abundant component in many edible plants, was found to be one of the major constituents of the aqueous methanol extract of Trifolium alexandrinum L. family Fabaceae, a fodder plant widely cultivated in Egypt. The estrogenic activity of LG concerning the effect on uterotrophy, lipid profile, weight gain and bone enhancement activity was determined in ovariectomized rat model at a dose of 5 mg/kg. Luteolin‐7‐O‐glycoside showed significant estrogenic effect through the preservation of normal uterine weight and plasma estradiol level. It also significantly inhibited the bone turnover markers plasma bone‐specific alkaline phosphatase, plasma osteocalsin, type I procollagen N‐terminal, and C‐telopeptide of type II collagen levels. It induced a significant improvement in plasma lipid profile. The effect of LG was comparable with estradiol with lower effect on uterine weight. Liver and kidney functions revealed a wide safety of LG at this dose level. The present study revealed that LG may be a promising hormone replacement therapy after being examined thoroughly on human. Copyright © 2016 John Wiley & Sons, Ltd.     

Reduction of fat storage in mice fed a high-fat diet long term by treatment with saponins prepared from Kochia scoparia fruit

The fresh fruit (Japanese name, Tonburi) of Kochia scoparia has been used as a food garnish in Japanese-style dishes from ancient times, and may prevent metabolic syndromes such as hyperlipidemia, hypertension, obesity and atherosclerosis. This study was performed to clarify whether an ethanol extract of K. scoparia fruit prevented obesity induced in mice by a high-fat diet for 9 weeks. The ethanol extract of K. scoparia fruit prevented the increases in body weight and parametrial adipose tissue weight induced by the high-fat diet. Furthermore, consumption of a high-fat diet containing 1% or 3% K. scoparia extract significantly increased the fecal content and the fecal triacylglycerol level at day 3 compared with those in the high-fat diet group. The ethanol extract (250 mg/kg) and total saponins (100 mg/kg) of K. scoparia inhibited the elevation of the plasma triacylglyccerol level 2 or 3 h after the oral administration of the lipid emulsion. Total saponins, momordin Ic, 2'-O-beta-d-glucopyranosyl momordin Ic and 2'-O-beta-d-glucopyranosyl momordin IIc isolated from K. scoparia fruit inhibited the pancreatic lipase activity (in vitro). These findings suggest that the anti-obesity actions of K. scoparia extract in mice fed a high-fat diet may be partly mediated through delaying the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity.     

Anti‐inflammatory Activity of Constituents Isolated from Aerial Part of Angelica acutiloba Kitagawa

Recently, the resources of medicinal plants have been exhausting. The root of Angelica acutiloba is one of the most important ingredients in Japanese Kampo medicine for the treatment of gynecological diseases. In our search for alternative medicinal plant resources of the root of A. acutiloba, we found that its aerial part has the anti‐inflammatory potency as well as the root. Phytochemical investigation of the aerial part resulted in the isolation of four compounds including a new dimeric phthalide, namely tokiaerialide (2), along with Z‐ligustilide (1), falcarindiol (3), and bergaptol (4). Next, we investigated the in vitro anti‐inflammatory activity of 1–4 in lipopolysaccharide‐stimulated RAW264 macrophages. Among the isolated compounds, 1 exhibited the most potent inhibition against lipopolysaccharide‐induced production of prostaglandin E₂, nitric oxide, and pro‐inflammatory cytokines (interleukin‐6 and tumor necrosis factor‐α). Compounds 3 and 4 also inhibited all inflammatory mediators, but their inhibitory abilities were weaker than those of 1. Furthermore, 1, 3, and 4 strongly also induced heme oxygenase‐1. These results suggest that 1, 3, and 4 potentially exert anti‐inflammatory activity, and the aerial part of A. acutiloba may be considered to be a useful medicinal resource for inflammatory diseases. Copyright © 2015 John Wiley & Sons, Ltd.     

Macrophage Immunomodulatory Activity of a Purified Polysaccharide Isolated from Ganoderma atrum

The objective of this study was to evaluate the immunomodulatory effects of the purified Ganoderma atrum polysaccharide (PSG‐1) on murine macrophage cell line RAW264.7. Phagocytotic assay by fluorescein isothiocyanate‐dextran internalization showed that PSG‐1 stimulated the phagocytosis of macrophages. G. atrum polysaccharide increased the production of NO, and the level of mRNA expression of inducible nitric oxide synthase in a dose–response manner. G. atrum polysaccharide also dose‐dependently induced the release of TNF‐α and interleukin‐1β. Generation of reactive oxygen species was promoted by PSG‐1, as determined by flow cytometry. Moreover, PSG‐1 induced nuclear factor‐κB activation by elevation of p65 nuclear translocation, suggesting that PSG‐1 probably stimulated macrophage activities by activating the nuclear factor‐κB pathway. Copyright © 2012 John Wiley & Sons, Ltd.     

Inhibitory effect of panduratin A isolated from Kaempferia panduarata Roxb. on melanin biosynthesis

Hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, thus melanin synthesis inhibitors have been of great interest as target molecules for cosmetic and medicinal purposes. The aim of this study was to investigate the in vitro inhibitory effect of panduratin A, isolated from Kaempferia pandurata Roxb., on melanogenesis and its related enzymes such as tyrosinase, tyrosinase related protein-1 (TRP-1) and tyrosinase related protein-2 (TRP-2) in melan-a murine melanocytes. The IC(50) values of panduratin A for melanogenesis and tyrosinase were 9.6 μm and 8.2 μm, respectively, while those of arbutin as a positive control were 990 μm and 660 μm, respectively. In western blot analysis, panduratin A also significantly decreased tyrosinase, TRP-1 and TRP-2 protein levels. These results indicate that panduratin A effectively inhibits melanin biosynthesis, thus creating the possibility of developing a new skin-whitening agent.     

番石榴叶总黄酮对慢性胰腺炎小鼠纤维化的影响

目的:探讨番石榴叶总黄酮(total flavonoids from Psidium guajava leaves,TFPGL)对慢性胰腺炎(chronic pancreatitis,CP)小鼠纤维化的影响及其机制。方法:将50只C57BL/6小鼠随机均分为正常组,CP模型组,oxidized ATP(oxATP)组,TFPGL低、高剂量组。后4组小鼠腹腔注射雨蛙素50μg·kg~(-1)·h-1(溶于200μL生理盐水),每天6次,每周3 d,连续6周,建立慢性胰腺炎小鼠模型。6周后,oxATP组腹腔注射oxATP(15μg·kg~(-1)·d-1,溶于200μL生理盐水)2周,TFPGL低、高剂量组分别予以TFPGL 0.186,0.372 g·kg~(-1)·d-1灌胃2周。同时,正常组小鼠腹腔注射与模型组等体积、等频率的生理盐水。苏木素-伊红(HE)染色评估胰腺损伤程度;天狼星红染色检测胰腺组织胶原含量;免疫组化检测α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA),核苷酸结合寡聚化结构域样受体3(nucleotide binding oligomerization domain-like receptor 3,NLRP3),半胱氨酸天冬氨酸蛋白酶-1(cysteinyl aspartate specific proteinase-1,Caspase-1)的蛋白表达水平;酶联免疫吸附法测定胰腺组织中IL-1β(interleukin-1β),IL-18水平。结果:与正常组比较,雨蛙素注射后胰腺损伤加重(P0.01),Caspase-1,NLRP3,α-SMA,IL-1β,IL-18水平升高(P0.01)。天狼星红染色显示胰腺组织细胞周围胶原Ⅰ(ColⅠ),胶原Ⅲ(ColⅢ)含量较正常组升高(P0.01)。与模型组比较,oxATP组及TFPGL低、高剂量组炎症损伤及纤维化程度均减轻,表现为天狼星红染色程度减轻(P0.05,P0.01),Caspase-1,NLRP3,α-SMA,IL-1β,IL-18水平均降低(P0.05,P0.01)。结论:TFPGL可通过抑制P2X7R介导NLRP3炎性体信号途径活化显著减轻慢性胰腺炎模型小鼠的慢性炎症及纤维化程度。     

20S proteasome inhibitory activity of flavonoids isolated from Spatholobus suberectus

The promising biological role of the ubiquitin proteasome pathway (UPP) in cancer therapy has recently emerged. Inhibition of proteasome has been proposed as a new therapeutic target for treatment of cancer. Bioassay‐guided fractionation of a MeOH extract of the stems of Spatholobus suberectus resulted in seven compounds, liquiritigenin (1), isoliquiritigenin (2), genistein (3), daidzein (4), medicarpin (5), 7‐hydroxyflavanone (6) and formononetin (7), which were evaluated for the first time for their inhibitory effect on 20S proteasome. Among the isolated compounds, 2, 3 and 6 exhibited inhibitory activities on human 20S proteasome with IC₅₀ values of 4.88 ± 1.5, 9.26 ± 1.2 and 5.21 ± 1.5 µm , respectively. Copyright © 2010 John Wiley & Sons, Ltd.