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1.
This study was designed to determine the changes in saponin content in American ginseng berries after treatment by heating and to assess the anticancer effects of the extracts. After steaming treatment (100-120 degrees C for 1 h, and 120 degrees C for 0.5-4 h), the content of seven ginsenosides, Rg1, Re, Rb1, Rc, Rb2, Rb3, and Rd, decreased; the content of five ginsenosides, Rh1, Rg2, 20R-Rg2, Rg3, and Rh2, increased. Rg3, a previously identified anticancer ginsenoside, increased significantly. Two hours of steaming at 120 degrees C increased the content of ginsenoside Rg3 to a greater degree than other tested ginsenosides. When human colorectal cancer cells were treated with 0.5 mg/mL steamed berry extract (120 degrees C 2 h), the antiproliferation effects were 97.8% for HCT-116 and 99.6% for SW-480 cells. At the same treatment concentration, the effects of unsteamed berry extract were 34.1% for HCT-116 and 4.9% for SW-480 cells. After staining with Hoechst 33258, apoptotic cells increased significantly by treatment with steamed berry extract compared with unheated extracts. Induction of apoptosis activity was confirmed by flow cytometry after staining with annexin V/PI. The steaming of American ginseng berries augments ginsenoside Rg3 content and increases the antiproliferative effects on two human colorectal cancer cell lines.  相似文献   

2.
Milled Piper methysticum roots were extracted sequentially with hot water and methanol. Cyclooxygenase (COX) enzyme inhibitory assay directed purification of the methanol extract yielded bornyl esters of 3,4-methylenedioxy cinnamic acid (1) and cinnamic acid (2), pinostrobin (3), flavokawain B (4), and 5,7-dimethoxyflavanone (5). The structures of compounds 1-5 were accomplished by spectral experiments. The aqueous extract contained previously reported kava lactones, as confirmed by TLC analysis. Compounds 3 and 5 were isolated for the first time from kava kava roots. Compound 4 showed the highest COX-I inhibitory activity at 100 microg/mL. All the compounds tested gave good COX-I and moderate COX-II enzyme inhibitory activities at 100 microg/mL. This is the first report of COX-I and -II inhibitory activities for compounds 1-5.  相似文献   

3.
Muscadine grapes have unique aroma and flavor characteristics. Although a few studies reported high polyphenols content of muscadine grapes, little research has been conducted to evaluate the phenolic compounds bioactivities in any muscadine grape cultivar. The objective of this study was to evaluate the effect of phenolic compounds in muscadine grapes on cancer cell viability and apoptosis. Four cultivars of muscadine (Carlos, Ison, Noble, and Supreme) were assessed in this study. Phenolic compounds were extracted from muscadine skins and further separated into phenolic acids, tannins, flavonols, and anthocyanins using HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC. Anthocyanin fractions were more than 90% pure. The effect of different fractions on the viability and apoptosis of two colon cancer cell lines (HT-29 and Caco-2) was evaluated. A 50% inhibition of cancer cell population growth for the two cell lines was observed at concentrations of 1-7 mg/mL for crude extracts. The phenolic acid fractions showed a 50% inhibition at the level of 0.5-3 mg/mL. The greatest inhibitory activity was found in the anthocyanin fraction, with a 50% inhibition at concentrations of approximately 200 microg/mL in HT-29 and 100-300 microg/mL in Caco-2. Anthocyanin fractions also resulted in 2-4 times increase in DNA fragmentation, indicating the induction of apoptosis. These findings suggest that polyphenols from muscadine grapes may have anticancer properties.  相似文献   

4.
Volatile chemicals obtained from a commercial beer by liquid-liquid continuous extraction were evaluated for antioxidant activity. The inhibitory ability of this extract toward the conversion of hexanal to hexanoic acid was monitored over a 35-day period. The volatile extract demonstrated >99% effectiveness at inhibiting hexanal oxidation at 50 microg/mL, comparable to that of the natural antioxidant alpha-tocopherol (vitamin E). Volatile compounds contained in the extract were isolated and identified by gas chromatography-mass spectrometry (GC-MS). From the volatile constituents identified in beer extract, phenylethyl alcohol, maltol, and 2-furanmethanol were examined for antioxidative activities. At a concentration of 500 microg/mL, maltol and 2-furanmethanol demonstrated approximately 95 and 100% inhibition of hexanal oxidation over 35 days, respectively. Phenylethyl alcohol did not show any appreciable level of inhibition of hexanal oxidation. Heterocyclic compounds, some of which are known to possess antioxidative activities, were also identified in the volatile extract.  相似文献   

5.
Piper betle, belonging to the Piperaceae family, is a tropical plant, and its leaf and inflorescence are popularly consumed by betel quid (BQ) chewers in Taiwan and many other South and Southeast Asian countries. However, little is known about the biochemical properties of inflorescence Piper betle (IPB) toward reactive oxygen species (ROS) and platelet functions. In the present work, aqueous IPB extract was shown to be a scavenger of H(2)O(2), superoxide radical, and hydroxyl radical with a 50% inhibitory concentration (IC(50)) of about 80, 28, and 73 microg/mL, respectively. IPB extract also prevented the hydroxyl radical induced PUC18 plasmid DNA breaks at concentrations higher than 40 microg/mL. Since ROS are crucial for platelet aggregation, we further found that IPB extract also inhibited the arachidonic acid (AA) induced and collagen-induced platelet aggregation, with an IC(50) of 207 and 335 microg/mL, respectively. IPB extract also inhibited the AA-, collagen- (>100 microg/mL of IPB), and thrombin (>250 microg/mL of IPB)-induced thromboxane B(2) (TXB(2)) production by more than 90%. However, IPB extract showed little effect on thrombin-induced aggregation. These results indicated that aqueous components of IPB are potential ROS scavengers and may prevent the platelet aggregation possibly via scavenging ROS or inhibition of TXB(2) production.  相似文献   

6.
Research has shown that diets rich in phenolic compounds may be associated with lower risks of several chronic diseases including cancer. This study systematically evaluated the bioactivities of phenolic compounds in rabbiteye blueberries and assessed their potential antiproliferation and apoptosis induction effects using two colon cancer cell lines, HT-29 and Caco-2. Polyphenols in three blueberry cultivars, Briteblue, Tifblue, and Powderblue, were extracted and freeze-dried. The extracts were further separated into phenolic acids, tannins, flavonols, and anthocyanins using an HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC with >90% purity in anthocyanin fractions. The dried extracts and fractions were added to the cell culture medium to test for antiproliferation activities and induction of apoptosis. Flavonol and tannin fractions resulted in 50% inhibition of cell proliferation at concentrations of 70-100 and 50-100 microg/mL in HT-29 and Caco-2 cells, respectively. The phenolic acid fraction showed relatively lower bioactivities with 50% inhibition at approximately 1000 microg/mL. The greatest antiproliferation effect among all four fractions was from the anthocyanin fractions. Both HT-29 and Caco-2 cell growth was significantly inhibited by >50% by the anthocyanin fractions at concentrations of 15-50 microg/mL. Anthocyanin fractions also resulted in 2-7 times increases in DNA fragmentation, indicating the induction of apoptosis. The effective dosage levels are close to the reported range of anthocyanin concentrations in rat plasma. These findings suggest that blueberry intake may reduce colon cancer risk.  相似文献   

7.
The bioassay-guided isolation and purification of the hexane extract of the cultured mycelia of Grifola frondosa led to the characterization of a fatty acid fraction and three compounds, ergosterol (1), ergostra-4,6,8(14),22-tetraen-3-one (2), and 1-oleoyl-2-linoleoyl-3-palmitoylglycerol (3). The composition of fatty acid fraction was confirmed as palmitic, oleic, and linoleic acids by GC-MS and by comparison with the retention values of authentic samples. The structures of compounds 1-3 were established by spectroscopic methods. The fatty acid fraction and compounds 1-3 showed cyclooxygenase (COX) enzyme inhibitory and antioxidant activities. The inhibition of COX-1 enzyme by the fatty acid fraction and compounds 1-3 at 250 microg/mL were 98, 37, 55, and 67%, respectively. Similarly, COX-2 enzyme activity was reduced by fatty acid fraction and compounds 1-3 at 250 microg/mL by 99, 37, 70, and 4%, respectively. The inhibitions of liposome peroxidation by the fatty acid fraction and compounds 1 and 2 at 100 microg/mL were 79, 48, and 42%, respectively. This is the first report of compounds 2 and 3 from the cultured mycelia of G. frondosa. The COX inhibitory activities of compounds 1-3 are reported here for the first time.  相似文献   

8.
The inhibitory activity of Curcuma longa L. (turmeric) rhizome constituents against sortase A, a bacterial surface protein anchoring transpeptidase, from Staphylococcus aureus ATCC 6538p was evaluated. The activity of the isolated compounds (1-4) was compared to that of the positive control,p-hydroxymecuribenzoic acid (pHMB). The biologically active components of C. longa rhizome were characterized by spectroscopic analysis as the curcuminoids curcumin (1), demethoxycurcumin (2), and bisdemethoxycurcumin (3). Curcumin was a potent inhibitor of sortase A, with an IC50 value of 13.8 +/- 0.7 microg/mL. Bisdemethoxycurcumin (IC50 = 31.9 +/- 1.2 microg/mL) and demethoxycurcumin (IC50 = 23.8 +/- 0.6 microg/mL) were more effective than pHMB (IC50 = 40.6 +/- 1.2 microg/mL). The three isolated compounds (1-3) showed no growth inhibitory activity against S. aureus strain Newman, with minimum inhibitory concentrations (MICs) greater than 200 microg/mL. Curcumin also exhibited potent inhibitory activity against S. aureus cell adhesion to fibronectin. The suppression of fibronectin-binding activity by curcumin highlights its potential for the treatment of S. aureus infections via inhibition of sortase activity. These results indicate that curcumin is a possible candidate in the development of a bacterial sortase A inhibitor.  相似文献   

9.
In this study, an in vitro nitric oxide (*NO)-generating system was used to investigate the *NO-scavenging effects of methanolic extracts of white ginseng (Panax ginseng C.A. Meyer), red ginseng, and sun ginseng and several ginsenosides and phenolic compounds. Sun ginseng extract showed the strongest activity among the three ginseng extracts. None of the ginsenosides used in this experiment showed *NO-scavenging activity, but the phenolic compounds, such as p-coumaric and vanillic acids, and maltol inhibited *NO production in a concentration-dependent manner. Moreover, maltol levels markedly increased by heat processing. Therefore, the enhanced *NO-scavenging activity of ginseng by heat processing was closely related to phenolic acids and the increased content of maltol.  相似文献   

10.
A method based on high-performance liquid chromatography (HPLC) and negative ion electrospray mass spectrometry (LC-MS) has been used to determine ginsenosides Rb1, Rc, and Re in six different samples of ginseng. These included a liquid extract, capsules, tea bags, and an instant tea. It was found that four of the six samples had detectable levels of at least one of the ginsenosides. The liquid extract, capsules, instant tea, and tea bags labeled ginseng had ginsenosides. The labels on the two samples that did not have ginsenosides indicated that they were a mixture of green tea, licorice, and ginseng. Also, 13C NMR was used to identify the types of complex carbohydrates present in the samples. One of the samples of tea bags had none of the ginsenosides, but did have complex carbohydrates found in most of the other samples. The instant tea had all three ginsenosides, but had no complex carbohydrates, only sucrose. The amounts of ginsenosides found in standard doses from six different sources of ginseng varied considerably. It was found that steeping a tea bag for a longer time than that recommended on the label produced a larger recovery of ginsenosides and that reusing a tea bag produced even higher recoveries.  相似文献   

11.
Volatiles were isolated from the dried inner bark of Tabebuia impetiginosa using steam distillation under reduced pressure followed by continuous liquid-liquid extraction. The extract was analyzed by gas chromatography and gas chromatography-mass spectrometry. The major volatile constituents of T. impetiginosa were 4-methoxybenzaldehyde (52.84 microg/g), 4-methoxyphenol (38.91 microg/g), 5-allyl-1,2,3-trimethoxybenzene (elemicin; 34.15 microg/g), 1-methoxy-4-(1E)-1-propenylbenzene (trans-anethole; 33.75 microg/g), and 4-methoxybenzyl alcohol (30.29 microg/g). The antioxidant activity of the volatiles was evaluated using two different assays. The extract exhibited a potent inhibitory effect on the formation of conjugated diene hydroperoxides (from methyl linoleate) at a concentration of 1000 microg/mL. The extract also inhibited the oxidation of hexanal for 40 days at a level of 5 microg/mL. The antioxidative activity of T. impetiginosa volatiles was comparable with that of the well-known antioxidants, alpha-tocopherol, and butylated hydroxytoluene.  相似文献   

12.
An active compound that inhibits cancer cells was isolated from the fruit of Prunus mume, and its structure and in vitro activities were characterized. The n-hexane fraction obtained from methanol extracts exhibited the strongest inhibitory effect on the growth of cancer cells. From the n-hexane fraction, a new compound named B-1 was purified through preparative thin-layer chromatography, ODS column chromatography, and reverse phase high-performance liquid chromatography and its structure was analyzed by fast atom bombardment mass spectrometry and 1H and 13C NMR. The molecular formula of B-1 was C19H22O6 {2-hydroxy-1-[(7-hydroxy-2-oxo-2H-chromen-6-yl)methyl]-2-methylpropyl-(2Z)-3-methyl-but-e-enoate:prunate}, and the IC50 value was in the range of 39-58 microg/mL in descending order of the cancer cell lines Hep-2, SW-156, HEC-1-B, and SK-OV-3. B-1 exhibited 81-96% inhibition at a concentration level of 100 microg/mL against all cells, based on an 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. However, B-1 showed little effect against normal cells with only 23% or less growth inhibition at 100 microg/mL. Thus, B-1 has a highly specific inhibitory effect against cancer cells but little effect against normal cells. When the cancer cell lines Hep-2 and SK-OV-3 were incubated with B-1 for 72 h, most of the tested cells suffered strong growth inhibition. The compound has the potential to be developed as a nutraceutical.  相似文献   

13.
Pollenosis is a disease that affects 1 in 10 of the Japanese population. During the season of cedar pollen dispersal, many patients suffer from symptoms such as sniffling, sternutation, and itching of the eyes. Japanese butterbur is a popular vegetable and is one of the few domestic vegetables in Japan. The anti type I allergic effects of an aqueous ethanol extract from aerial parts of Japanese butterbur (JBE) were evaluated in rats and RBL-2H3 mast cells. In the passive cutaneous anaphylaxis reaction in rats, a single oral treatment of JBE (1000 mg/kg) was found to suppress the reaction. In IgE-sensitized RBL-2H3 cells, JBE (10-100 microg/mL) inhibited beta-hexosaminidase release, leukotriene C(4)/D(4)/E(4) synthesis, and TNF-alpha production. Moreover, a high concentration of JBE (1000 microg/mL) suppressed smooth muscle constriction induced by histamine (10 microM) and leukotriene D(4) (10 nM) in a guinea pig trachea strip. The search for components in JBE with an inhibitory activity on mast cell degranulation was guided by inhibition of beta-hexsosaminidase release. Two eremophilane-type sesquiterpenes, six polyphenolic compounds, and two triterpene glycosides were isolated. Of these compounds, fukinolic acid, a principal polyphenol constituent, showed potent inhibitory activity (IC(50) value = 2.1 microg/mL). Consequently, On the basis of its inhibition of mast cell activation and direct smooth muscle reaction induced by released mediators, JBE was found to suppress the type I allergic reaction.  相似文献   

14.
Grape and its cell culture extracts are rich in flavonoids and stilbenes that are biologically active. The objective of this study was to evaluate possible inhibitory effects of grape (a Vitis hybrid Bailey Alicant A) cell culture extract and subfractions on human DNA topoisomerase II catalytic activity and to characterize constituents in the most potent fractions. At 5 microg/mL, grape cell crude extract and Toyopearl (TP) fractions 2-6 provided significantly greater inhibition of topoisomerase II catalytic activity than quercetin, a chemopreventive agent previously known as a topoisomerase catalytic inhibitor. The most potent topoisomerase II catalytic inhibitors from grape cell culture extracts in descending order of potency were TP fractions 4 and 6 (IC(50) = 0.28-0.29 microg/mL), TP-3 (IC(50) = 0.74 microg/mL), and crude extract (IC(50) = 1.02 microg/mL); each was significantly more potent than resveratrol (IC(50) = 18.0 microg/mL), another well-known chemopreventive topoisomerase II catalytic inhibitor. Using both high-performance liquid chromatography and liquid chromatography electrospray ionization mass spectrometry, constituents in TP-4 and TP-6 were characterized. These constituents included cyanidin-3,5-diglucoside, malvidin-3-acetylglucoside, peonidin-3-coumaryl-5-diglucoside, procyanidin B(1), procyanidin B(2), procyanidin B(5), procyanidin dimer digallate, procyanidin C(1), myricetin, and rutin, none of which have been previously characterized from grape cell cultures. The significant potency especially of TP-4 and TP-6 from grape cell cultures suggests that these fractions may have potential as chemopreventive agents.  相似文献   

15.
The nitrification inhibition (NI) bioassay guided fractionation of the methanol extract of lyophilized and milled roots of Leuceana leucocephala resulted in the isolation of four compounds, 1-4, as confirmed from their 1H and 13C NMR spectral data. Compound 1, gallocatechin, was the most active NI inhibitor at 12 microg/mL. Epigallocatechin, 2, and epicatechin, 4, isolated as mixtures, were not assayed individually for their NI inhibitory activities against the nitrification bacterium Nitrosomonas europaea.  相似文献   

16.
The antioxidant ferulic and caffeic acid phenolics are ubiquitous in plants and abundant in fruits and vegetables. We have synthesized a series of ferulic and caffeic acid esters and tested for tumor cell proliferation, cyclooxygenase enzymes (COX-1 and -2) and lipid peroxidation inhibitory activities in vitro. In the tumor cell proliferation assay, some of these esters showed excellent growth inhibition of colon cancer cells. Among the phenolics esters assayed, compounds 10 (C12-caffeate), 11 (C16-caffeate), 21 (C8-ferulate), and 23 (C12-ferulate) showed strong growth inhibition with IC50 values of 16.55, 13.46, 18.67, and 7.57 microg/mL in a breast cancer cell line; 9.65, 7.45, 17.05, and 4.35 microg/ mL in a lung cancer cell line; 5.78, 3.5, 4.29, and 2.46 microg/mL in a colon cancer cell line; 12.04, 12.21, 14.63, and 8.09 microg/ mL in a central nervous system cancer cell line; and 8.62, 7.76, 11.0, and 5.37 in a gastric cancer cell line. In COX enzyme inhibitory assays, ferulic and caffeic acid esters significantly inhibited both COX-1 and COX-2 enzymes. Caffeates 5-10 (C4-C12), inhibited COX-1 enzyme between 50% and 90% and COX-2 enzyme by about 70%, whereas ferulates 15-21 (C3-C8) inhibited COX-1 and COX-2 enzymes by 85-95% 25 microg/mL. Long-chain caffeates 11-14 (C16-C22) and short-chain ferulates 15-20 (C3-C5) were the most active in lipid peroxidation inhibition and showed 60-70% activity at 5 microg/mL concentration.  相似文献   

17.
Antioxidant and cyclooxygenase activities of fatty acids found in food   总被引：6，自引：0，他引：6  
Several commercially available C-8 to C-24 saturated and unsaturated fatty acids (1-29) were assayed for cyclooxygenase-I (COX-I) and cyclooxygenase-II (COX-II) inhibitory and antioxidant activities. Among the saturated fatty acids tested at 60 microg mL(-1), there was an increase in antioxidant activity with increasing chain length from octanoic acid to myristic acid (C-8-C-14) and a decrease thereafter. All unsaturated fatty acids tested at 60 microg mL(-1) showed good antioxidant activity except for undecylenic acid (12), cis-5-dodecenoic acid (13), and nervonic acid (29). The highest inhibitory activities among the saturated fatty acids tested on cyclooxygenase enzymes COX-I and COX-II were observed for decanoic acid to lauric acid (3-5) at 100 microg mL(-1). Similarly, among the unsaturated fatty acids tested, the highest activities were observed for cis-8,11,14-eicosatrienoic acid (25) and cis-13,16-docosadienoic acid (27) at 100 microg mL(-1).  相似文献   

18.
The bioactive hexane extract of Daucus carota seed yielded 2,4,5-trimethoxybenzaldehyde (1), oleic acid (2), trans-asarone (3), and geraniol (4). Compounds 1-4 were evaluated for their mosquitocidal, nematicidal, antifeedant, and antimicrobial activities. Only trans-asarone was active in the assays performed, causing 100% mortality to fourth-instar mosquito larvae, Aedes aegyptii, at 200 microg mL(-1) and the nematodes Caenorhabditis elegans and Panagrellus redivivus at 100 microg mL(-1). In feeding trials, trans-asarone also caused significant weight reductions of the caterpillars Helicovarpa zea, Heliothis virescens, and Manduca sexta when incorporated into artificial diet at a concentration of 100 microg mL(-1). Also, it exhibited slight activity at 100 microg mL(-1) against the yeasts Candida albicans, Candida parapsilasis, and Candida kruseii.  相似文献   

19.
A method for simultaneous determination of ginsenosides and polyacetylenes in Panax quinquefolium L. (American ginseng) roots was developed. The ginsenosides Rb1, Rb2, Rc, Rd, Re, Rg1, Ro, malonyl-Rb1, malonyl-Rc, and malonyl-Rd and the polyacetylenes falcarinol and panaxydol were extracted from fresh ginseng roots in a sequential extraction process with 100% methanol followed by 80% aqueous methanol and quantified simultaneously in extracts by high-performance liquid chromatography using diode array detection. Separations were achieved with a phosphate buffer-acetonitrile gradient system using an RP-C18 column. Except for Rd, the present extraction method resulted in similar or significantly higher concentrations of both ginsenosides and polyacetylenes in comparison to commonly used extraction methods for these compounds. The contents of polyacetylenes and ginsenosides were determined in the root hairs, lateral roots, and main roots of 6 year old ginseng plants. The total mean concentrations of ginsenosides and polyacetylenes in root hairs were 31.0 g/kg fresh weight (FW) and 2.6 g/kg FW, respectively, whereas the concentrations of these bioactive compounds in the main roots were significantly lower with total mean concentrations of 17.8 g/kg FW for ginsenosides and 0.6 g/kg FW for polyacetylenes. The concentration of individual and total ginsenosides and polyacetylenes did not differ significantly between main roots of different sizes. Consequently, it is possible to do quantitative screening for ginsenosides and polyacetylenes to breed ginseng roots with higher levels of bioactive compounds.  相似文献   

20.
Four methods were tested for extraction and recovery of six major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) found in roots of American ginseng (Panax quinquefolius): method A, sonication in 100% methanol (MeOH) at room temperature (rt); method B, sonication in 70% aqueous MeOH at rt; method C, water extraction (90 degrees C) with gentle agitation; and method D, refluxing (60 degrees C) in 100% MeOH. After 0.5-1 h, the samples were filtered and analyzed by high-performance liquid chromatography (HPLC)-UV. A second extraction by methods C and D was done, but 85-90% of ginsenosides were obtained during the first extraction. Lyophilization of extracts did not influence ginsenoside recovery. Method D resulted in the highest significant recoveries of all ginsenosides, except Rg1. Method C was the next most effective method, while method A resulted in the lowest ginsenoside recoveries. Method B led to similar recoveries as method C. All methods used one filtration step, omitted time-consuming cleanup, but maintained clear peak resolution by HPLC, and can be used for quantitative screening of ginsenosides from roots and commercial ginseng preparations.  相似文献   

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