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1.
The present study investigated the antibacterial effect of four extracts from the fruitbody of the edible medicinal mushroom Hericium erinaceus (hot water extract, HWE; microwave/50% ethanol extract, MWE; acid extract, ACE; and alkaline extract, AKE) against murine salmonellosis. The extracts had no effect on Salmonella ser. Typhimurium growth in culture. Nor were the extracts toxic to murine macrophage cells, RAW 264.7. HWE and MWE stimulated uptake of the bacteria into the macrophage cells as indicated by increased colony-forming unit (CFU) counts of the contents of the lysed macrophages infected with Salmonella Typhimurium for 30 and 60 min. Two hours postinfection, the bacterial counts increased in the macrophages, but 4 and 8 h postinfection the HWE- and MWE-treated cells showed greater activity against the bacteria than the control. HWE- and MWE-treated noninfected macrophages had altered morphology and elevated inducible nitric oxide (NO) synthase (iNOS) mRNA expression. In the presence of S. Typhimurium, iNOS mRNA expression was further increased, accompanied by an increase in NO production. Histology assays of the livers of mice infected with a sublethal dose (1 × 10(4) CFU) of S. Typhimurium showed that HWE and MWE, administered by daily intraperitoneal injection, protected against necrosis of the liver, a biomarker of in vivo salmonellosis. The lifespans of mice similarly infected with a lethal dose of S. Typhimurium (1 × 10(5) CFU) were significantly extended by HWE and MWE. β-Glucan, known to stimulate the immune system, was previously found to be present in high amounts in the active extracts. These results suggest that the mushroom extract activities against bacterial infection in mice occur through the activation of innate immune cells.  相似文献   

2.
A new liquid rice hull smoke extract with a smoky aroma and sugar-like odor prepared by pyrolysis of rice hulls followed by liquefaction of the resulting smoke contained 161 compounds characterized by GC/MS. Antioxidative, antiallergic, and anti-inflammatory activities of the extract were assessed in vitro and in vivo. At pH 5, the extract inhibited 1-diphenyl-2-picrylhydrazyl (DPPH) free radicals and suppressed nitric oxide (NO) and β-hexosaminidase releases from lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophage leukemia cells and ionophore A23187-stimulated RBL-2H3 rat basophilic cells without significant cytotoxicity. 12-O-Tetradecanolylphorbol-13-acetate (TPA) was applied to the ears of CD-1 mice to induce inflammation (edema), which was accompanied by increases in a series of biomarkers. Topical application of 1% of the extract as well as feeding mice a standard diet with 1% extract for two weeks significantly reduced the expression of biomarkers associated with the TPA-induced inflammation. These include tumor necrosis factor-α (TNF-α), IL-1β, interleukin-1β (IL-1β), interleukin-6 (IL-6), leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)), myeloperoxidase (MPO). These in vitro and in vivo findings demonstrate the potential value of rice hull smoke extract derived from a major agricultural byproduct to serve as a new biomaterial for the improvement of food quality and safety and the environment.  相似文献   

3.
Red koji has been recognized as a cholesterol-lowering diet supplement because of it contains fungi metabolites, monacolins, which reduce cholesterol synthesis by inhibiting HMG-CoA reductase. In this study, water extracts of red koji were loaded onto a C(18) cartridge, and the acetonitrile eluate was collected as test fraction. Red koji water extracts and its C(18) cartridge acetonitrile eluent had total phenols concentrations of 5.57 and 1.89 mg/g of red koji and condensed tannins concentrations of 2.71 and 1.20 mg/g of red koji, respectively. Both exhibited an antioxidant activity and an inhibitory activity to mushroom tyrosinase. The higher antioxidant activity of the red koji acetonitrile eluent was due to the existence of a high percentage of condensed tannins. The results from the kinetic study for inhibition of mushroom tyrosinase by red koji extracts showed that the compounds in the extracts competitively inhibited the oxidation of tyrosine catalyzed by mushroom tyrosinase with an ID(50) of 5.57 mg/mL.  相似文献   

4.
The lentinan contents in the Lentinus edodes fruit body during storage were examined by ELISA method using anti-lentinan antibodies. The lentinan content (12.8 mg.g(-)(1) dw) before storage decreased to 3.7 mg.g(-)(1) dw over 7 days at 20 degrees C. However, it only slightly decreased at 1 degrees C and only decreased to 9.3 mg. g(-)(1) dw at 5 degrees C. Glucanase activity, which seems to be associated with lentinan degradation, increased more during storage of L. edodes at 20 degrees C than it did at lower temperatures. In addition, only glucose was detected as a degraded product from lentinan by the glucanase. This suggested that this enzyme would fit the profile of an exo-type glucanase. Also, polyphenol oxidase activity, known as an index of freshness reduction in the mushroom, increased approximately 2.7-fold (to 61.5 units.mg(-)(1)) over 7 days during storage at 20 degrees C. However, its activity changed little during storage at lower temperatures. These results indicate that the reduction during storage of the quality of L. edodes as a functional food is accompanied by the decrease of lentinan, and by browning, and that exo-glucanase plays an important role in the decrease of lentinan content.  相似文献   

5.
Polyphenolic compounds in cranberries have been investigated to determine their role in protection against cardiovascular disease and some cancers. Extracts of whole fruit were assayed for radical-scavenging activity and tumor growth inhibition using seven tumor cell lines. Selective inhibition of K562 and HT-29 cells was observed from a methanolic extract in the range of 16-125 microg/mL. Radical-scavenging activity was greatest in an extract composed primarily of flavonol glycosides. Seven flavonol glycosides were isolated and purified from whole fruit for further evaluation; the anthocyanin cyanidin 3-galactoside was also purified for comparison with the flavonoids. Three flavonol monoglycosides were newly identified by (13)C NMR as myricetin 3-alpha-arabinofuranoside, quercetin 3-xyloside, and 3-methoxyquercetin 3-beta-galactoside (isorhamnetin); the other four isolated were the previously identified myricetin 3-beta-galactoside, quercetin 3-beta-galactoside, quercetin 3-alpha-arabinofuranoside, and quercetin 3-alpha-rhamnopyranoside. These compounds were evaluated for 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity and ability to inhibit low-density lipoprotein oxidation in vitro. Most of the flavonol glycosides showed antioxidant activity comparable or superior to that of vitamin E; cyanidin 3-galactoside showed activity superior to that of the flavonoids as well as vitamin E or Trolox in both antioxidant assays.  相似文献   

6.
菌糠复合基质在番茄育苗上的效果   总被引:10,自引:0,他引:10  
以发酵菌糠为试验材料,研究了菌糠与草炭、蛭石、炉渣以不同比例(V/V)混合后基质的理化性质,并以复合基质进行了番茄育苗试验。结果表明,发酵菌糠的总孔隙度、持水孔隙度比草炭低11.8%、36.8%,通气孔隙度比草炭高41.9%,电导率比草炭高12.5倍。菌糠以30%~70%的比例与蛭石、草炭混合后,复合基质的理化性质与CK(草炭∶蛭石=7∶3)相近。在番茄育苗试验中,以T3(菌糠∶蛭石=7∶3)表现最好,T4(菌糠∶草炭∶蛭石=5∶2∶3)、T5(菌糠∶草炭∶蛭石=3∶4∶3)育苗效果均优于CK。  相似文献   

7.
The antidiabetic effects of Mung bean sprout (MBS) extracts and Mung bean seed coat (MBSC) extracts were investigated in type 2 diabetic mice. Male KK-A (y) mice and C57BL/6 mice were used in this study. In KK-A (y) mice, the blood glucose, plasma C-peptide, glucagon, total cholesterol, triglyceride, and blood urea nitrogen (BUN) levels were significantly higher than those in the C57BL/6 mice ( P < 0.001, P < 0.001, P < 0.01, P < 0.001, P < 0.01, and P < 0.01). In addition, KK-A (y) mice showed an obvious decrease in insulin immunoreactivity in pancreas as well. MBS and MBSC were orally administrated to KK-A (y) mice for 5 weeks. It was found that MBS (2 g/kg) and MBSC (3 g/kg) lowered blood glucose, plasma C-peptide, glucagon, total cholesterol, triglyceride, and BUN levels and at the same time markedly improved glucose tolerance and increased insulin immunoreactive levels. These results suggest that MBS and MBSC exert an antidiabetic effect in type 2 diabetic mice.  相似文献   

8.
Pleurotus citrinopileatus is a popular edible mushroom which is physiologically active in both humans and animals. In the study we investigate the effects of this mushroom on hyperlipidemic hamster rats. Four dietary forms of the mushroom were created as follows. The powdered dry fruiting body, hot-water extract, and two kinds of elutes were obtained, from ethyl acetate extract and methanol extract, respectively, in different mixed proportion solvents over silica gel column chromatography (referred to as EAE and MOE, respectively). They were tested at different dosages as a supplement to a high-fat diet in hyperlipidemic rats. Serum triglycerides and total cholesterol levels were significantly lower in groups supplemented with the highest dosages of EAE and MOE (0.5 g/kg, body weight daily) as compared with the control groups that received no mushroom additive. High-density lipoprotein levels in these same two experimental groups were also significantly higher than those in the negative control group. The tested rats that were fed with EAE had the highest serum glutathione peroxidase and superoxide dismutase activity, and those with the MOE and EAE had the highest DPPH free radical scavenging activities and ferric-reducing abilities, tested in vitro. The major constituents of MOE and EAE were identified as ergosterol and nicotinic acid, respectively. P. citrinopileatus extracts may have a significant antihyperlipidemia effect. Furthermore, antioxidant activities and antihyperlipidemic effects of MOE and EAE seemed to display similar tendencies.  相似文献   

9.
菇渣发酵园艺基质的理化性状和应用效果   总被引:14,自引:0,他引:14  
利用菇渣等固体废弃物生产园艺基质是充分利用自然资源的环保措施。利用工厂化生产金针菇的菇渣为主要原料,加入一定比例的尿素、芝麻渣、发酵微生物等辅料,通过充分堆制发酵生产园艺基质。试验表明,菇渣发酵后按照体积比6:4的比例与蛭石混合是最佳配方。黄瓜和网纹甜瓜的栽培试验表明,混配的菇渣基质可以降低生产成本,提高产量和品质,是一种优质的环保型有机园艺基质。  相似文献   

10.
芦荟粗提物对苹果采后灰霉病的防治效果与机理   总被引:4,自引:2,他引:2  
为了探讨芦荟粗提物对苹果采后抗灰霉病的效果及其机理。该试验将供试苹果分别用类黄酮质量浓度为0.020,0.035,0.050 g/L的芦荟粗提物浸泡5 min,常温下(23±1)℃放置2 d后,接种灰葡萄孢孢子悬浮液,以清水浸泡作为对照。结果表明:芦荟粗提物可显著降低果实灰霉病的发生率(P0.05),抑制病斑直径的扩展。经过4d的贮藏,类黄酮质量浓度为0.035和0.050 g/L的芦荟粗提物处理的苹果发病率分别为73%和53%,显著低于对照处理(93%)。芦荟粗提物处理能诱导红富士苹果果实的过氧化物酶、多酚氧化酶、苯丙氨酸解氨酶、几丁质酶、β-1,3-葡聚糖酶活性的提高,诱导酚类物质的合成,增强果实的抗病性。其中以类黄酮质量浓度为0.050 g/L的芦荟粗提物处理效果较好,与对照差异显著(P0.05);当类黄酮质量浓度大于0.050 g/L时,杀菌效果仍可增强,但会在果实上表面留下残留物。该研究结果也可为其他水果采后病害的防治研究提供参考。  相似文献   

11.
There is significant interest in the direct antioxidant activities of dietary polyphenols, due to associations between consumption of polyphenol-rich foods, such as fruits and vegetables, and decreased incidence of oxidative-stress related disease. However, indirect antioxidant action, such as the inhibition of ROS-producing enzymes, may be equally relevant to health benefits through a general reduction in oxidative stress in vivo. To this end, the effects of food extracts and individual compounds on the in vitro activity of xanthine oxidase (XO) were assessed, many for the first time. Several compounds were shown to be potent inhibitors in vitro, including hesperetin and theaflavin-3,3'-digallate with IC50 values of 39 and 49 microM, respectively. Of the extracts, cranberry juice, purple grape juice, and black tea were the most potent, with IC50 values of 2.4, 3.5, and 5.8% of extracts, respectively. Some samples were shown to promote XO activity over the concentration ranges tested, including orange juice and pink grapefruit juice. Certain "inhibitors", such as purple grape juice and black tea, promoted XO activity at low concentration. The possible role of dietary inhibitors of XO in reducing oxidative stress in vivo is discussed.  相似文献   

12.
A novel antitumor protein, coded as TBWSP31, was isolated from tartary buckwheat water-soluble extracts and purified by DEAE-Sepharose Fast Flow anion exchange, Sephadex G-100 gel filtration, and Sephacryl S-200 gel filtration column chromatography. TBWSP31 was identified to a homogeneous fraction by native PAGE. The antitumor effect of TBWSP31 against human mammary cancer cell Bcap37 was measured by an MTT assay. TBWSP31 showed higher antitumor activity, and time- and concentration-dependent effects were observed. SDS-PAGE analysis showed that TBWSP31 is composed of a single polypeptide with an approximate molecular weight of 57 kDa. TBWSP31 was rich in Glx (Gln+Glu), Arg, and Asx (Asp+Asn) according to amino acid analysis. Secondary structural analysis by CD spectroscopy revealed that TBWSP31 has the following: alpha-helix (33.9%), beta-sheet (22.8%), beta-turn (11.3%), and random coil (32.0%).  相似文献   

13.
The metabonomics changes of plasma and brain tissue after dietary supplementation with blueberry extracts (BBE) and cyanidin-3-O-galactoside from blueberry (BBM) in aged mice were investigated by (1)H NMR technique. The mice received intragastric administration of BBE (200 mg/kg/day), BBM (50 mg/kg/day), and saline water (0.9%) for 6 weeks, respectively, in the BBE, BBM, and control groups. At the end of the experiment, plasma and brain samples were collected for NMR analysis. The results demonstrated that the level of choline in plasma from BBE and BBM groups were obviously elevated relative to the control group, whereas the levels of lactate and phosphocholine in plasma were remarkably reduced. Compared with those in the control group, the levels of choline and GABA in the brain from the BBE group were obviously increased, whereas glutamate and phosphocholine in the BBE group were significantly decreased. The level of taurine in the brain from the BBM group was particularly higher than that in the control group. These results indicated supplementation with BBE or BBM might induce similar changes of endogenous plasma and brain metabolic profiles in aged mice.  相似文献   

14.
The antioxidant and antimicrobial activities of ethyl acetate extracts obtained from acid hydrolysates of several lignocellulosic materials (Eucalyptus globulus wood, barley bran, corn cobs, and corn leaves) were evaluated. The minimum inhibitory and bactericide concentrations (MIC and MBC, respectively) were determined against a selection of bacteria and yeasts. Extracts from Eucalyptus wood hydrolysates were the most active for inhibiting bacteria and yeast growth, with MIC in the range of 10(2)--5 x 10(3) microg/mL and MBC in the range of 10(3)--0(5) microg/mL. Bacteriogenic and bacteriostatic activities of extracts from Eucalyptus wood and barley bran acid hydrolysates were slightly higher than those of corn cobs and leaves. Both the radical scavenging capacity and the inhibition of the beta-carotene bleaching caused by extracts were determined and compared with those of synthetic antioxidants. The antioxidant activity of extracts increased with their concentrations in the media, the stronger properties corresponding to those obtained from Eucalyptus wood hydrolysates.  相似文献   

15.
Renal protective effects of naringenin at 0.5, 1, and 2% of the diet in diabetic mice were examined. Naringenin supplemented at 1 and 2% increased its deposit in liver and kidney of diabetic mice. Compared with the diabetic control group, naringenin treatments at 1 and 2% lowered plasma levels of glucose and blood urea nitrogen, as well as increased insulin level and creatinine clearance (P < 0.05). Naringenin treatments dose-dependently reduced renal tumor necrosis factor-α level and expression (P < 0.05) but only at 1 and 2% significantly decreased production and expression of interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein-1 (P < 0.05). Naringenin intake at 2% decreased renal formation and expression of type IV collagen, fibronectin, and transforming growth factor-β1 (P < 0.05). This compound at 1 and 2% lowered protein kinase C activity and suppressed nuclear factor κB (NF-κB) p65 activity, mRNA expression, and protein production in kidney. However, this agent only at 2% diminished NF-κB p50 activity, mRNA expression, and protein production (P < 0.05). These results indicate that naringenin could attenuate diabetic nephropathy via its anti-inflammatory and antifibrotic activities.  相似文献   

16.
Seven legume extracts containing phytoestrogens were analyzed for estrogenic activity. Methanol extracts were prepared from soybean (Glycine max L.), green bean (Phaseolus vulgaris L.), alfalfa sprout (Medicago sativa L.), mung bean sprout (Vigna radiata L.), kudzu root (Pueraria lobata L.), and red clover blossom and red clover sprout (Trifolium pratense L.). Extracts of kudzu root and red clover blossom showed significant competitive binding to estrogen receptor beta (ERbeta). Estrogenic activity was determined using an estrogen-dependent MCF-7 breast cancer cell proliferation assay. Kudzu root, red clover blossom and sprout, mung bean sprout, and alfalfa sprout extracts displayed increased cell proliferation above levels observed with estradiol. The pure estrogen antagonist, ICI 182,780, suppressed cell proliferation induced by the extracts, suggesting an ER-related signaling pathway was involved. The ER subtype-selective activities of legume extracts were examined using transiently transfected human embryonic kidney (HEK 293) cells. All seven of the extracts exhibited preferential agonist activity toward ERbeta. Using HPLC to collect fractions and MCF-7 cell proliferation, the active components in kudzu root extract were determined to be the isoflavones puerarin, daidzin, genistin, daidzein, and genistein. These results show that several legumes are a source of phytoestrogens with high levels of estrogenic activity.  相似文献   

17.
研究了维生素C(Vc)、茶多酚(TP)以及牛至(Origanum vulgare)和鼠尾草(Salvia farinacea)等植物提取物对鲜牛肉的护色效果。采用4℃冰箱冷藏经处理过的鲜牛肉1个星期,使其发生氧化反应,然后测定其生成的变肌红蛋白的相对含量和pH值,并配合色泽感官评定来评价提取物的抗氧化性能。结果表明:Vc与TP复配剂的抗氧化性明显好于单一抗氧化剂的抗氧化性,其最佳配比为Vc250mg/L、TP32.5mg/L;在复配的基础上分别添加牛至500mg/L、鼠尾草300mg/L的抗氧化效果最好。  相似文献   

18.
茄子秸秆水提物自毒作用初探   总被引:20,自引:0,他引:20  
试验研究茄子秸秆水提物自毒作用结果表明,茄子干秸秆水提物原液浓度为0 .0 15 g/ mL时明显抑制茄时明显抑制茄子胚根的生长,低浓度提取物原液对胚芽生长有一定促进作用,当其浓度增至0 .0 75g/ mL时明显抑制茄时茄子胚芽生长也受抑,表明茄子秸秆水提物对茄子生长有较强的自毒作用;水提物中醇溶性组分对茄子胚根、胚芽生长的影响与水提物原液表现一致,且对水培茄子幼苗生长有较强抑制作用,表明醇溶性组分中含有大量自毒物质。茄子幼苗根系活力随水提物中醇溶性组分浓度的增加而降低,植株对NO-3 、PO3 -4、K 、Mg2 和Ca2 等离子的吸收受阻,因而抑制离子的吸收是水提物中自毒物质发挥作用的重要因素之一。  相似文献   

19.
20.
Mushroom dietary fiber or nonstarch polysaccharides (NSPs) that were soluble in hot alkali and belonged to the beta-glucan type were isolated from the sclerotia of an edible mushroom, Pleurotus tuber-regium. The mushroom NSPs were further separated into a number of fractions [hot alkali extracts (HAEs)] with weight-average molecular weights (M(w)) ranging from 1 x 10(4) to 42.2 x 10(4). The HAE fractions [with M(w) of (5.8-17.1) x 10(4)] administered intraperitoneally at a dose of 20 mg/kg of body weight to BALB/c mice implanted with solid tumor Sarcoma 180 were found to be effective in inhibiting tumor proliferation with an inhibition ratio of > or =50%. In vitro experiments using human tumor cell lines HL-60 and HepG2 had shown that HAE fractions with M(w) of (5.8-42.2) x 10(4) also had antiproliferative activity at three different concentrations (50, 100, and 200 microg/mL) toward the tumor cell lines tested. All HAE fractions did not inhibit the growth of a normal kidney cell line (Vero) from monkey. It is therefore postulated that the antitumoral effect of NSPs from the sclerotia of P. tuber-regium is probably host-mediated and cytocidal.  相似文献   

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