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1.
Anthocyanin pigments in the berries of bagua?u (Eugenia umbelliflora Berg), a tropical fruit from Brazil, were extracted with 0.1% HCl in ethanol, and the crude anthocyanin extract was purified by Amberlite XAD-7 open-column chromatography. Six major anthocyanins were isolated by preparative HPLC, and their chemical structures were identified by spectroscopic methods (TLC, UV-vis, MS, and (1)H NMR). Delphinidin 3-O-beta-glucopyranoside, cyanidin 3-O-beta-glucopyranoside, petunidin 3-O-beta-glucopyranoside, pelargonidin 3-O-beta-glucopyranoside, peonidin 3-O-beta-glucopyranoside, and malvidin 3-O-beta-glucopyranoside were identified. On the basis of chromatographic data the total anthocyanin content was 342 mg/100 g of fresh bagua?u berries. Therefore, the concomitant presence of six anthocyanins in a single plant species makes this product promising as a new pigment source.  相似文献   

2.
It has been reported that epigallocatechin-3-O-(3″-O-methyl)-gallate (EGCG3″Me) and the EGCG3″Me-rich green tea ( Camellia sinensis L.) cultivar 'Benifuuki' exhibit antiallergic effects. The objective of this study was to investigate the effect of various tea leaf catechins on histamine release from murine bone marrow mast cells (BMMC). At a dose of 50 μg/mL, the rank order of histamine release inhibition was observed to be epicatechin-3-O-(3″-O-methyl)-gallate (ECG3″Me) > gallocatechin-3-O-(3″-O-methyl)-gallate (GCG3″Me) > EGCG3″Me > gallocatechin-gallate (GCG) > catechin-gallate (CG) > EGCG > epicatechin-gallate (ECG) > epigallocatechin (EGC) > gallocatechin (GC). Of the various tea cultivars analyzed by HPLC, the greatest content of ECG3″Me was found in the third crop of 'Benifuuki' (1.05% dry weight). Moreover, ECG3″Me content was positively correlated with EGCG3″Me content in 'Benifuuki' tea leaves. In an assay of mixtures of ECG3″Me and EGCG3″Me, inhibitory activity (50 μg/mL in total) was increased as the content of ECG3″Me increased. This suggests that ECG3″Me might link to the antiallergic effect of 'Benifuuki' tea, as has been reported for EGCG3″Me.  相似文献   

3.
The objective of this work was to improve the purity of β-(1→3)(1→6)-glucan in the native triple helical structure from the fruiting bodies of Pleurotus sajor-caju for effective biological function using cell wall-degrading enzymes. A crude carbohydrate was extracted with hot water, then treated with crude xylanase and cellulase from Paenibacillus curdlanolyticus B-6. β-Glucan in the extract was purified to homogeneity with a single and symmetrical peak using 650M DEAE Toyopearl and Sepharose CL-6B column chromatography. The purity of β-glucan was confirmed by high-performance size-exclusion chromatography. Purified β-glucan was obtained at a purity of up to 90.2%. The Congo red reaction and atomic force microscopy indicated that the purified β-glucan exhibited a triple helix conformation. Purified β-glucan was able to effectively up-regulate the functions of macrophages such as nitric oxide (NO) and tumor necrosis factor (TNF-α) production.  相似文献   

4.
5.
Two previous studies have reported that pu-erh tea contains a high level of γ-aminobutyric acid (GABA), which is the major inhibitory neurotransmitter in the central nervous system and has several physiological functions. However, two other researchers have demonstrated that the GABA content of several pu-erh teas was low. Due to the high value and health benefits of GABA, analysis of mass-produced pu-erh tea is necessary to determine whether it is actually enriched with GABA. A high-performance liquid chromatography (HPLC) method was developed for the determination of GABA in tea, the results of which were verified by amino acid analysis using an Amino Acid Analyzer (AAA). A total of 114 samples of various types of Chinese tea, including 62 pu-erh teas, 13 green teas, 8 oolong teas, 8 black teas, 3 white teas, 4 GABA teas, and 16 process samples from two industrial fermentations of pu-erh tea (including the raw material and the first to seventh turnings), were analyzed using HPLC. Statistical analysis demonstrated that the GABA content in pu-erh tea was significantly lower than that in other types of tea (p < 0.05) and that the GABA content decreased during industrial fermentation of pu-erh tea (p < 0.05). This mass analysis and comparison suggested GABA was not a major bioactive constituent and resolved the disagreement GABA content in pu-erh tea. In addition, the GABA content in white tea was found to be significantly higher than that in the other types of tea (p < 0.05), leading to the possibility of producing GABA-enriched white tea.  相似文献   

6.
Experimental (N979-5-2-4 and IA95111) and traditional oat lines (Jim and Paul) with average %β-glucan of 7.5, 7.8, 4.9, and 4.4%, respectively, were grown in 2002, 2003, and 2004. Molecular weight (MW) distributions of the β-glucans were examined for potential variations among growing years and for relationships with pasting properties measured by Rapid ViscoAnalyser under three separate conditions: 1) in silver nitrate (SN) solution to inactivate enzymes; 2) hydrolyzed by α-amylase to eliminate the effect of starch; and 3) treated with lichenase to remove β-glucan. The β-glucan was extracted by a process involving multiple precipitation and dialysis steps, and the MW distributions were determined by HPLC. %β-Glucan in N979-5-2-4 and IA95111 lines were consistently and significantly greater (P < 0.05) than in Jim and Paul lines during three growing years. The contribution of β-glucan to peak viscosity on the RVA was substantially greater than that of the starch for all three years. The molecular number average and peak MW of β-glucan from N979-5-2-4 and IA95111 were greater than these values for Jim and Paul, and values were consistent among years. The MW of extracted β-glucan was associated with pasting properties after amylase hydrolysis, but not after treatment with lichenase or in SN solution.  相似文献   

7.
The seeds of peas (Pisum sativum) and chickpeas (Cicer arietinum) expressing a gene for α-amylase inhibitor-1 (αAI) from the common bean (Phaseolus vulgaris) are protected from damage by old world bruchids (pea and cowpea weevils). Here, we used electrospray ionization time-of-flight mass spectrometry to compare the post-translational modifications of αAI from transgenic sources with the processed forms of the protein from several bean varieties. All sources showed microheterogeneity with differences in the relative abundance of particular variants due to differences in the frequency of addition of glycans, variable processing of glycans, and differences of C-terminal exopeptidase activity. The structural variation among the transgenics was generally within the range of the bean varieties. Previously, mice showed allergic reactions following ingestion of transgenic pea αAI but not bean αAI. Here, only minor differences were observed following intraperitoneal sensitization. Both of the transgenic pea and bean forms of αAI elicited Th1 and Th2 antibody isotype responses, suggesting that both proteins are immunogenic and could potentially be allergenic.  相似文献   

8.
4-(3,4-Dihydroxybenzoyloxymethyl)phenyl-O-β-d-glucopyranoside (DBPG), a polyphenolic glycoside, isolated from Origanum vulgare has shown 1,1-diphenyl-2-picrylhydrazyl (DPPH(?))-scavenging capacity in previous work. This study demonstrated that DBPG exhibits antioxidant activity by a series of DPPH(?), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS(?+)), and superoxide anion radical (O(2)(?-)) radical-scavenging assays. The inhibition of lipid peroxidation (LP) by DBPG exceeded that by l-ascorbic acid (AA) in a liposome model system. Adding DBPG to mouse liver and brain tissue inhibited the formation of thiobarbituric acid reactive substances (TBARS) to a greater extent than did trolox. In the oxygen stress test, BNLCL2 and HaCaT cells pretreated with DBPG showed increased activities of glutathione peroxidase (GPx), perhaps as a result of reduction of the production of reactive oxygen species (ROS). These findings proved that DBPG had antioxidant activities and a cytoprotective effect in hepatocytes and keratinocytes, suggesting that DBPG may be a useful food and cosmetic additive.  相似文献   

9.
10.
Mashua (Tropaeolum tuberosum Ruíz and Pavón), an Andean tuber with high antioxidant activity, has sparked interest because of its traditional medicinal use. In this study, we evaluated the anthocyanin composition for three purple mashua genotypes and their contribution to the overall antioxidant activity of the tuber. Mashua anthocyanins, total phenolics, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) antioxidant activity ranged from 45.5 to 131.9 mg of cyanidin 3-glucoside equivalents/100 g fresh weight (FW), 174.9 to 275.5 mg of gallic acid equivalents/100 g of FW, and 16.2 to 45.7 micromol of Trolox equivalents/g of FW, respectively. The high-performance liquid chromatography with photodiode array detection (HPLC-DAD) and HPLC-electrospray ionization tandem mass spectrometry (ESI/MS-MS) profiles revealed the presence of 11 different anthocyanins. The two major pigments (56.4-73.0% total area range at 520 nm) were identified as delphinidin 3-glucoside-5-acetylrhamnoside and delphinidin 3-sophoroside-5-acetylrhamnoside. Other pigments were delphinidin 3-glucoside-5-rhamnoside, delphinidin 3-sophoroside-5-rhamnoside, delphinidin 3-glucoside, cyanidin 3-sophoroside, and cyanidin 3-sophoroside-5-rhamnoside. Cyanidin 3-glucoside and cyanidin 3-rutinoside were only found in two genotypes, while pelargonidin 3-sophoroside and pelargonidin 3-sophoroside-5-rhamnoside were only found in the third one. Anthocyanins from mashua were the major contributors to the total ABTS values for only one of the three genotypes, suggesting that other phenolics present are playing a major role in the antioxidant power of mashua tubers. Results from this study provide important information for the Nutraceutical and Functional Food Market for the use of mashua anthocyanins not only as a source of natural colorants but also as a source of phytonutrients.  相似文献   

11.
Glycosylated α-galactosidase (melibiase) has been purified from white chickpea ( Cicer arietinum ) to 340-fold with a specific activity of 61 units/mg. Cicer α-galactosidase showed a M(r) of 45 kDa on SDS-PAGE and by MALDI-TOF. The optimum pH and temperature with pNPGal were 4.5 and 50 °C, respectively. The K(m) for hydrolysis of pNPGal was 0.70 mM. Besides hydrolyzing the pNPGal, Cicer α-galactosidase also hydrolyzed natural substrates such as melibiose, raffinose, and stachyose very effectively; hence, it can be exploited commercially for improving the nutritional value of soy milk. Galactose was found to be a competitive inhibitor. The property of this enzyme to cleave the terminal galactose residues can be utilized for converting the group B erythrocytes to group O erythrocytes.  相似文献   

12.
The physiological significance of 5-(3',4'-dihydroxyphenyl)-γ-valerolactone, an important metabolite derived from the catabolism of flavan-3-ols by gut microbiota, has been often overlooked due to the lack of the commercial standard. In the present work, this metabolite has been chemically synthesized, and its analytical parameters and antioxidant capacity have been determined in comparison to other chemical analogues [isomer 3-(3',4'-dihydroxyphenyl)-δ-valerolactone and γ-valerolactone] and other structurally related compounds [(+)-catechin, (-)-epicatechin, and 3-(3,4-dihydroxyphenyl)-propionic acid]. The synthesized compound was also used to perform a targeted analysis in samples collected during the in vitro fermentation of a grape seed flavan-3-ol extract with human fecal microbiota from three healthy volunteers. The time-course formation of 5-(3',4'-dihydroxyphenyl)-γ-valerolactone revealed large interindividual differences among volunteers, with concentrations ranging from 3.31 to 77.54 μM at 10 h of fermentation. These results are further discussed in view of the scarce reports quantifying 5-(3',4'-dihydroxyphenyl)-γ-valerolactone in in vitro fermentation studies, and pharmacokinetic and intervention studies.  相似文献   

13.
Partial acid hydrolysis of the tetrasaccharide (lycotetraose) side chain of the tomato glycoalkaloid α-tomatine resulted in the formation of four products with three, two, one, and zero carbohydrate side chains, which were separated by high-performance liquid chromatography (HPLC) and identified by thin-layer chromatography (TLC) and liquid chromatography ion-trap time-of-flight mass spectrometry (LCMS-IT-TOF). The inhibitory activities in terms of IC(50) values (concentration that inhibits 50% of the cells under the test conditions) of the parent compound and the hydrolysates, isolated by preparative HPLC, against normal human liver and lung cells and human breast, gastric, and prostate cancer cells indicate that (a) the removal of sugars significantly reduced the concentration-dependent cell-inhibiting effects of the test compounds, (b) PC3 prostate cancer cells were about 10 times more susceptible to inhibition by α-tomatine than the breast and gastric cancer cells or the normal cells, (c) the activity of α-tomatine against the prostate cancer cells was 200 times greater than that of the aglycone tomatidine, and (d) the activity increased as the number of sugars on the aglycone increased, but this was only statistically significant at p < 0.05 for the normal lung Hel299 cell line. The effect of the alkaloids on tumor necrosis factor α (TNF-α) was measured in RAW264.7 macrophage cells. There was a statistically significant negative correlation between the dosage of γ- and α-tomatine and the level of TNF-α. α-Tomatine was the most effective compound at reducing TNF-α. The dietary significance of the results and future research needs are discussed.  相似文献   

14.
(E)-β-farnesene is a strong and efficient alarm pheromone in most aphid species. However, applications in agriculture are prevented by its relatively high volatility, its susceptibility to oxidation and its complex and expensive synthesis. To develop novel compounds for aphid control, we have designed and synthesized analogues of (E)-β-farnesene, containing a pyrazole moiety present in several insecticides. Their structures have been confirmed by 1H NMR, elemental analysis, high-resolution mass spectroscopy and IR. Binding activities to three odorant-binding proteins (OBPs) of the pea aphid Acythosiphon pisum have been evaluated and correlated with their structures with reference to (E)-β-farnesene. Several derivatives were shown both to bind to A. pisum OBPs with a specificity similar to that of (E)-β-farnesene and to have aphicidal activity comparable to that of thiacloprid, a commercial insecticide. The compounds synthesized in this work represent new potential agents for aphid population control and provide guidelines to design analogues of (E)-β-farnesene endowed with both insecticidal and repellent activity for aphids.  相似文献   

15.
A murine hepatoma (Hepa 1c1c7) cellular bioassay was used to guide the isolation of phase II enzyme inducers from fermented soy sauce, using quinone reductase (QR) as a biomarker. A crude ethyl acetate extract, accounting for 8.7% of nonsalt soluble solids of soy sauce, was found to double relative QR specific activity at 25 μg/mL (concentration required to double was defined as a "CD value"). Further silica gel column fractionation yielded 17 fractions, 16 of which exhibited CD values for QR induction of <100 μg/mL. The four most potent fractions were subfractionated by column and preparative thin layer chromatography, leading to the isolation and identification of two phenolic compounds (catechol and daidzein) and two β-carbolines (flazin and perlolyrin), with respective CD values of 8, 35, 42, and 2 μM. Western blots confirmed that the increases in QR activity corresponded to dose-dependent increases in cellular levels of NAD[P]H:quinone oxidoreductase 1 protein by these four QR inducers. To the authors' knowledge, this is the first report on the ability of β-carboline-derived alkaloids to induce phase II enzymes.  相似文献   

16.
Production, purification, and characterization of a novel β-1,3-1,4-glucanase (lichenase) from thermophilic Rhizomucor miehei CAU432 were investigated. High-level extracellular β-1,3-1,4-glucanase production of 6230 U/mL was obtained when oat flour (3%, w/v) was used as a carbon source at 50 °C. The crude enzyme was purified to homogeneity with a specific activity of 28818 U/mg. The molecular weight of purified enzyme was estimated to be 35.4 kDa and 33.7 kDa by SDS-PAGE and gel filtration, respectively. The optimal pH and temperature of the enzyme were pH 5.5 and 60 °C, respectively. The K(m) values of purified β-1,3-1,4-glucanase for barley β-glucan and lichenan were 2.0 mM and 1.4 mM, respectively. Furthermore, the gene (RmLic16A) encoding the β-1,3-1,4-glucanase was cloned and its deduced amino acid sequence showed the highest identity (50%) to characterized β-1,3-1,4-glucanase from Paecilomyces thermophila. The high-level production and biochemical properties of the enzyme enable its potential industrial applications.  相似文献   

17.
Genetic Resources and Crop Evolution - The loss of agrobiodiversity is a topic of global impact. On a local scale, Lombardy, in the Alpine macro-Region, has lost more than 78% of its plant...  相似文献   

18.
The possible adverse effects on health of diet-derived advanced glycation endproducts (AGEs) and advanced lipoxidation endproducts (ALEs) is of current interest. This study had the objective of determining the effects of the addition of AGE/ALE inhibitors and different types of sugar and cooking oil on Nε-(carboxymethyl)lysine (CML) and Nε-(carboxyethyl)lysine (CEL) formation in model foods (sponge cakes). The cake baked using glucose produced the highest level of CML (2.07±0.24 mmol/mol lysine), whereas the cake baked using fructose produced the highest concentration of CEL (25.1±0.15 mmol/mol lysine). There were no significant differences between CML concentrations formed in the cakes prepared using different types of cooking oil, but significant differences (P<0.001) were observed between the cakes prepared using different proportions of cooking oil. The cakes containing oil generated greater concentrations of CML than sucrose. α-Tocopherol and rutin did not inhibit CML and CEL formation. In contrast, ferulic acid and thiamin, thiamin monophosphate, and thiamin pyrophosphate reduced CML and CEL formation.  相似文献   

19.
Four flavonol glycosides were isolated from an extract of sea buckthorn pomace (Hippopha? rhamnoides) by Sephadex LH-20 gel chromatography and semipreparative HPLC. Their structures were elucidated by hydrolysis studies, ESI-MS(n), UV, and (1)H and (13)C NMR spectroscopy. The occurrence of the major flavonol glycoside kaempferol 3-O-beta-sophoroside-7-O-alpha-rhamnoside in sea buckthorn is described here for the first time. A further 21 flavonol glycosides of Sephadex LH-20 fractions of sea buckthorn pomace were characterized by HPLC-DAD-ESI-MS. The characteristic MS-MS and MS(3) fragmentation pattern of flavonol glycosides previously identified in sea buckthorn juice and of flavonol glycosides identified by NMR spectroscopy gave valuable indications for their identification. The results demonstrate that loss of the sugar moiety from C-7 of the aglycon is more favored than fission of the glycosidic linkage at the C-3 position. Thus, most of the compounds identified were 7-rhamnosides of isorhamnetin, kaempferol, and quercetin, which exhibit different substitution patterns at the C-3 position, mainly glucosides, rutinosides, and sophorosides. In addition, numerous flavonol glycosides were detected lacking a sugar moiety at C-7. Finally, eight flavonol derivatives were identified that are acylated by hydroxybenzoic or hydoxycinnamic acids.  相似文献   

20.
β3-肾上腺素能受体基因(β3-adrenergic receptor,ADRB3)的突变影响动物机体的产热机能。为了探讨绵羊ADRB3基因多态性与生产性能的相关性,本研究以甘肃高山细毛羊(Ovis aries)为研究对象,采用PCR-SSCP方法,检测ADRB3基因部分内含子序列的遗传多态性,分析不同等位基因及基因型与其生长速度的相关性。结果表明,甘肃高山细毛羊群体中检测到5种等位基因(A、B、C、D和E),构成7种基因型(AA、AD、BD、BE、CC、CD和DD),存在6个突变位点(T/C、C/T、A/G/C、T/C、A/C和T/C),其中等位基因D和基因型CD频率分别为0.4159和0.2540,为优势等位基因和基因型;与生长速度相关性分析发现,不同基因型对生长速度影响不同,其中基因型差异与二月龄体重显著相关(P0.05),与其他阶段生长速度相关性不显著(P0.05);含有等位基因A和D或基因型AD和BD的群体平均体重优于其他群体,BE基因型个体生长速度最低。本研究发现,甘肃高山细毛羊ADRB3基因内含子区具有丰富的多态性;等位基因A和D可作为甘肃高山细毛羊群体生产性能选育的有效分子标记,基因型AD和BD可作为肉用杂交改良中的有效标记,可用于指导绵羊肉用性能改良。  相似文献   

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