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1.
Liquorice (root of Glycyrrhiza uralensis FISCH) is an ingredient of candies and used as a popular medicine in Europe and oriental countries. Cyclosporine (CsA), an immunosuppressant with narrow therapeutic window, is widely used in transplant patients. The absorption and disposition of CsA were associated with P-glycoprotein (P-gp) and cytochrome P450 3A4 (CYP3A4). This study investigated the effects of liquorice extract (LE) and its major ingredient, glycyrrhizin (GZ), on CsA pharmacokinetics in rats. The results indicated that LE and GZ significantly decreased the peak blood concentration and the areas under the curves of CsA in rats. Mechanism studies revealed that glycyrrhetic acid (GA), the major metabolite of GZ, significantly activated the functions of P-gp and CYP3A4. In conclusion, liquorice significantly reduced the oral bioavailability of CsA through activating P-gp and CYP3A4.  相似文献   

2.
The pharmacokinetics of resveratrol in 11 healthy male volunteers has been assessed in a randomized, crossover, controlled clinical trial after the administration of three grape products: red wine (250 mL), grape juice (1/L), or tablets (red wine extracts enriched with trans-resveratrol). Doses of trans-resveratrol independently of the product administered, were about 14 μg/kg. Biological samples were collected and analysed by capillary gas chromatography–mass spectrometry. cis-Resveratrol, trans-resveratrol and dihydroresveratrol were determined in plasma and urine. Plasma concentration of trans-resveratrol after hydrolysis increased as a response to all grape products and that of cis-resveratrol after wine and grape juice. Free forms of these phenolic compounds were deemed undetectable in plasma. Despite similar trans-resveratrol doses being administered, its bioavailability from wine and grape juice was 6-fold higher, than that from tablets. Resveratrol was better absorbed from natural grape products than from tablets, pointing out the importance of the matrix in its bioavailability.  相似文献   

3.
A limited amount of research suggests that oral ingestion of pinitol (3-O-methyl-d-chiro-inositol) positively influences glucose tolerance in humans. This study assessed the effects of different doses of pinitol supplementation on glucose tolerance, insulin sensitivity and plasma pinitol concentrations. Thirty healthy subjects underwent two one-day trials in which they consumed a nutritive beverage (Fruit Up®) containing 2.5, 4.0 or 6.0 g of pinitol and a corresponding placebo equivalent in both energy and carbohydrates. Blood samples were collected frequently over the 240-min test period. The pinitol-enriched beverage reduced serum glucose and insulin at 45 and 60 min, but only at a dose of 6.0 g. Plasma pinitol concentrations, maximum concentration and AUC increased according to the dose administered. The results show that a single dose of pinitol from a naturally-occurring food ingredient at the highest dose administered acutely influences indices of whole-body glucose tolerance and insulin sensitivity in healthy subjects.  相似文献   

4.
Food allergy has become a public health problem that continues to challenge both the consumer and the food industry. The objectives of this study were to evaluate the reduction of immunoreactivity by natural and induced fermentation of soybean meal (SBM) with Lactobacillus plantarum, Bifidobacterium lactis, Saccharomyces cereviseae, and to assess the effect on amino acid concentration. Immunoreactivity of commercially available fermented soybean products and ingredients was also evaluated. ELISA and western blot were used to measure IgE immunoreactivity using plasma from soy sensitive individuals. Commercial soy products included tempeh, miso and yogurt. Fermented SBM showed reduced immunoreactivity to human plasma, particularly if proteins were <20 kDa. S. cereviseae and naturally fermented SBM showed the highest reduction in IgE immunoreactivity, up to 89% and 88%, respectively, against human pooled plasma. When SBM was subjected to fermentation with different microorganisms, most of the total amino acids increased significantly (p < 0.05) and only few of them suffered a decrease depending on the type of fermentation. All commercial soy containing products tested showed very low immunoreactivity. Thus, fermentation can decrease soy immunoreactivity and can be optimized to develop nutritious hypoallergenic soy products. However, the clinical relevance of these findings needs to be determined by human challenge studies.  相似文献   

5.
The amino acid (AA) composition and physicochemical and conformational properties of protein isolate (SNPI), globulin (SNG) and albumin (SNA) fractions from soapnut seeds were evaluated. The essential AA of SNG, SNA and SNPI (except sulfur-containing AA) are sufficient for the FAO/WHO suggested requirements for 2–5 year old infants. SNG and SNPI showed similar electrophoresis patterns and AA compositions, the subunit of those proteins consisted of two polypeptides linked by disulfide bonds. In contrast, SNA showed a different AA compositions and SDS–PAGE pattern. Both SNG and SNPI presented a typical U-shape protein solubility (PS)–pH profile, SNA showed a completely different PS–pH profile, especially at pH 2.0–4.0. The near-UV circular dichroism (CD), differential scanning calorimetry (DSC) and tryptophan fluorescence spectra analyses indicated that the flexibility in tertiary conformations decreased in the order: SNA > SNPI > SNG, while soapnut proteins had a similar secondary conformation, with a highly ordered structure (the β-types), as evidenced by far-UV CD spectra.  相似文献   

6.
The heat and pH stability of prebiotic non-digestible wheat bran-derived arabinoxylooligosaccharides (AXOS), xylooligosaccharides (XOS)-and chicory root inulin-derived fructooligosaccharides (FOS) were compared. Heat stability (at 100 and 121 °C) and shelf-life measurements (at 4 and 37 °C) revealed decomposition at alkaline pH (pH 11.0) for all three preparations tested. The short chain oligosaccharides, XOS and FOS (apparent peak molecular mass of 400 and 800 Da, respectively), were more sensitive to alkaline decomposition than were the longer chain AXOS (apparent peak molecular mass of 1500 Da), the latter being the result of the higher abundancy of reducing ends in short chain oligosaccharide preparations. At pH 2.0 and 3.0, hydrolysis of oligosaccharide linkages took place, with FOS being the most acid-sensitive component.  相似文献   

7.
The electrochemical behaviour and the antioxidant effectiveness of ascorbic acid (AA), caffeic acid (CA), quercetin (Q), catechin (Cat), hesperetin (H) and their equimolar binary mixtures were evaluated by means of cyclic voltammetry and luminol Co(II)–EDTA chemiluminescence, respectively, with a view to the prediction of a potential prooxidant or synergistic behaviour of mixtures of antioxidants. An important synergistic oxidation between Q and Cat was observed. The mixture CA/AA manifested the most prooxidant tendency among all the tested compounds and their mixtures. AA increased the antioxidant activity of Q and decreased that of Cat. Q and Cat regenerated CA, the prooxidant effect of the mixtures increasing with less e-delocalisation. Cat and CA have an antagonistic effect. H has the closest oxidation potential to CA and a slight increase of its antioxidant activity was registered when mixed with CA, which was not the case when it was combined with the other compounds or measured alone.  相似文献   

8.
This article reports a study of the concentrations of dietary fiber (DF) and antioxidant capacity in fruits (pulp and oil) of a new açaí (Euterpe oleraceae) cultivar—‘BRS-Pará’, with a view to determine the possibility of using it as a source of antioxidants in functional foods or dietary supplements. Results show that ‘BRS-Pará’ açaí fruits has a high content of DF (71% dry matter) and oil (20.82%) as well as a high antioxidant capacity in both defatted matter and oil. ‘BRS-Pará’ Açaí fruits can be considered as an excellent source of antioxidant dietary fiber. Antioxidant capacity of açaí ‘BRS-Pará’ oil by DPPH assay was higher (EC50 = 646.3 g/g DPPH) than extra virgin olive oil (EC50 = 2057.27 g/g DPPH). These features provide açaí ‘BRS-Pará’ fruits with considerable potential for nutritional and health applications.  相似文献   

9.
Little is known about the content and development of pyranoanthocyanins, pigments mainly formed during red wine ageing, in commercial wines. Some of the major pyranoanthocyanins in a wide selection of 1–10 years-old Spanish Tempranillo wines and also in a 29 years wide-vertical series of Tempranillo wines from an individual cellar have been determined. Great variability in pyranoanthocyanin concentrations was found (range, mg/l): vitisin A, 0–10.76; pinotin A, 0–4.26; and malvidin 3-glucoside-4-vinylphenol, 0.03–1.37. Vitisin A and malvidin 3-glucoside-4-vinylphenol were already present in 1–2 years-old wines, whereas pinotin A was only detectable in a few of the 1 and 2 years-old wines. Vitisin A tended to decrease with wine age, while hydroxyphenyl-pyranoanthocyanins showed the reverse trend. However, the aforementioned trends were interrupted by various temporary maxima, most likely due to some “refreshment” of the oldest wines (i.e., addition of young wine), as suggested by unexpected high concentrations of malvidin 3-glucoside, in contrast to the results found in the wine vertical series. The effects of addition of young wine on aged wine pyranoanthocyanin concentrations were confirmed by wine refreshment experiments.  相似文献   

10.
Two baking times (9 and 24 min) and storage temperatures (4 and 25 °C) were used to explore the impact of heat exposure during bread baking and subsequent storage on amylopectin retrogradation, water mobility, and bread crumb firming. Shorter baking resulted in less retrogradation, a less extended starch network and smaller changes in crumb firmness and elasticity. A lower storage temperature resulted in faster retrogradation, a more rigid starch network with more water inclusion and larger changes in crumb firmness and elasticity. Crumb to crust moisture migration was lower for breads baked shorter and stored at lower temperature, resulting in better plasticized biopolymer networks in crumb. Network stiffening, therefore, contributed less to crumb firmness. A negative relation was found between proton mobilities of water and biopolymers in the crumb gel network and crumb firmness. The slope of this linear function was indicative for the strength of the starch network.  相似文献   

11.
The mature peptide of Thermomonospora fusca xylanase A (TfxA) was successfully expressed in Pichia pastoris under the control of AOX1 promoter. The activity of recombinant T. fusca xylanase A (reTfxA) in culture supernatant was 117.3 ± 2.4 U/mg, which is 3 times higher than that of the native TfxA. The optimal temperature and pH for reTfxA were 60 °C and 6.0, respectively. When treated at 70 °C and pH 6.0 for 2 min, the residual activity of the reTfxA was 70%. The reTfxA was very stable over a wide pH range (5.0–9.0). After incubation over pH 5.0–9.0 at 25 °C for 1 h, all the residual activity of reTfxA was over 80%. The Km and kcat values for reTfxA were 2.45 mg/ml and 139 s−1, respectively. HPLC analysis revealed that xylobiose (X2) was the main hydrolysis product released from birchwood xylan and wheat bran insoluble xylan by reTfxA. Hydrolysis results of xylooligosaccharides showed that reTfxA was an endo-acting xylanase and xylobiose, xylotriose (X3), xylotetraose (X4), xylopentaose (X5), and xylohexaose (X6) could be hydrolysed. This is the first report on the expression of reTfxA in yeast and on the determining and quantifying of the hydrolysis products released from xylans and xylooligosaccharides by reTfxA.  相似文献   

12.
Large amounts of floral bio-residues are wasted in saffron spice production, which need to be stabilized because of how quickly they deteriorate. These bio-residues are rich in phenolic compounds, and the aim of this study was to evaluate the effect of drying temperatures and air flows on their color and phenolic composition. Anthocyanins and flavonols were degraded at 110 and 125 °C. The best drying temperatures were 70 and 90 °C for maintaining their physicochemical quality. The duration at 70 °C was double than that of 90 °C. Anthocyanins and flavonols were stable at 70 and 90 °C with 2, 4, 6 and 8 m s−1. Dehydrations at 90 °C with 2, 4 and 6 m s−1 were the most appropriate, due to a better color and greater similarity to control samples for their flavonols and anthocyanins.  相似文献   

13.
Yearling steers were fed 70:30 forage:concentrate diets for 205 d, with either grass hay (GH) or red clover silage (RC) as the forage source, and concentrates containing either sunflower-seed (SS) or flaxseed (FS), each providing 5.4% oil to diets. Feeding diets containing SS versus FS significantly improved growth and carcass attributes (P < 0.05), significantly reduced meat off-flavor intensity (P < 0.05), and significantly increased intramuscular proportions of vaccenic (t11-18:1), rumenic (c9,t11-CLA) and n − 6 fatty acids (FA, P < 0.05). Feeding diets containing FS versus SS produced significantly darker and redder meat with greater proportions of atypical dienes (P < 0.05). A significant forage × oilseed type interaction (P < 0.05) was found for n − 3 FA, α-linolenic acid, and conjugated linolenic acid, with their greatest intramuscular proportions found when feeding the RC-FS diet. Feeding GH versus RC also significantly improved growth and carcass attributes, sensory tenderness (P < 0.05) and significantly influenced intramuscular FA composition (P < 0.05), but overall, forage effects on FA profiles were limited compared to effects of oilseed.  相似文献   

14.
The interaction between oat β-glucan and other food components has the potential to influence starch digestibility and consequently affect its bioactivity in reducing glycemic responses. Blood glucose concentrations were measured before and after ingesting wheat and oat granolas, with 0.6 and 6.2 g of β-glucan, respectively, and two starch doses (40 and 60 g). As the in vitro extract viscosity of β-glucan increased, the in vitro starch digestibility was reduced and the glucose responses were lowered. The peak blood glucose response (PBGR) and the incremental area under the curve (iAUC) were lower in the 40 g than in the 60 g starch formulation. β-Glucan was significantly more active in reducing PBGR and iAUC when the β-glucan/starch ratio was 1.6:10 rather than 1.1:10. This information is valuable for new product development and for quality assessment of bioactive foods containing oat β-glucan.  相似文献   

15.
Teas from Maté have been widely consumed for centuries in Brazil, Argentina, Paraguay, and Uruguay. We now determine how age, growth conditions and post-harvesting processes of leaves from Ilex paraguariensis affect the concentration of bioactive compounds and their antioxidant capacity. Phenolics, xanthines, and carbohydrates were identified and quantified by electrospray ionisation mass spectrometry (ESI-MS) and ultra performance liquid chromatography (UPLC), which dramatically reduces the time for each analysis (<3 min). On average, sun-exposed (monoculture) leaf extracts exhibited higher levels of bioactive compounds as compared to shaded (forest grown) ones. PCA (principal component analysis) analysis of all the samples indicated that those obtained after blanching and drying contained more phenolics and a smaller concentration of xanthine than those in natura. The oxidised leaves had lower concentrations of phenolics, and consequently a decline in antioxidant activity. No differences were found based on the leaf age.  相似文献   

16.
Lycium barbarum has been used as a traditional Chinese medicine (TCM) to nourish liver and kidney, and brighten the eye. The fruits are dried or freshly squeezed for their juice and concentrated for beverages. Among various constituents, a group of polysaccharides (LBP) with a Glycan-O-Ser glycopeptide structure has been most researched and considered to be important for the efficacy of L. barbarum. Studies indicate effects of L. barbarum on aging, neuroprotection, general well-being, fatigue/endurance, metabolism/energy expenditure, glucose control in diabetics, glaucoma, anti-oxidant properties, immunomodulation, anti-tumor activity and cytoprotection. In addition to TCM, L. barbarum can be sold as a dietary supplement or classified as a food based upon the long and safe traditional usage. This review is to provide background and updated information of chemical constituents and efficacies with safety including a new direction for research and current regulatory situation of L. barbarum.  相似文献   

17.
Eugenia jambolana Lam. (syn. Syzigium cumini (L.) SKEELS; S. jambolana DC; Family: Myrtaceae), commonly known as black plum or Jamun is a plant native to India. Annually the trees produce oblong or ellipsoid fruits (berries). They are green when raw and purplish black when fully ripe. The ripe fruits are sweetish sour to taste and are used to prepare health drinks, squashes, juices, jellies and wine. Studies have shown that the berries contain carbohydrates, minerals and the pharmacologically active phytochemicals like flavonoids, terpenes, and anthocyanins. Jamun is a plant with known ethnomedicinal uses. Before the discovery of insulin, Jamun was useful in the treatment of diabetes and is an integral part in the various alternative systems of medicine. Scientific studies have shown that the various extracts of Jamun possess a range of pharmacological properties such as antibacterial, antifungal, antiviral, anti-genotoxic, anti-inflammatory, anti-ulcerogenic, cardioprotective, anti-allergic, anticancer, chemopreventive, radioprotective, free radical scavenging, antioxidant, hepatoprotective, anti-diarrheal, hypoglycemic and antidiabetic effects. The present paper reviews these aspects and also addresses the lacunas in the existing knowledge.  相似文献   

18.
Fruit of wolf (Solanum lycocarpum A. St. - HILL), found in Brazilian cerrado, has been used in the initial ripening stage as flour and/or starch in popular medicine due to its hypoglycemiant action. The aim of this work was to study the occurrence of phytochemical compounds, physical, chemical and technological characteristics of fruit of wolf flour and starch in the initial ripening stage. Flour and starch were extracted using known popularly and experimental methods (with sodium bisulfite) and chemical composition and technological characteristics were analyzed. The results were comparatively assessed by Tukey's test (p < 0.05). The recommendation for use was the extraction of flour and starch products by previously removing peels and seeds of fruit of wolf. The most relevant finding in this study is the high content of fibers in flour (23 g/100 g) and high content of resistant starch (32 g/100 g) in the fraction of starch extracted from fruit of wolf, which can explain their use as hypoglycemic agent.  相似文献   

19.
20.
Response surface methodology was used to model and optimise the production of ethyl butyrate, catalysed by Rhizopus oryzae lipase immobilised in a hydrophilic polyurethane foam. Experiments were carried out following a central composite rotatable design, as a function of reaction temperature (T: 22–38 °C) initial butyric acid concentration (A: 0.031–0.619 M) and initial molar ratio ethanol/acid (MR; 0.257–2.443). After 48 h reaction time, the production of ethyl butyrate could be fitted to a surface described by a second-order polynomial model. A maximum ethyl butyrate concentration of 0.106 M, corresponding to 47% conversion into ester and a productivity of 2.21 μmole/mL h, is expected at initial reaction conditions of T, A and MR of 33 °C, 0.225 M and 1.637, respectively. This maximum was experimentally confirmed.  相似文献   

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