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1.
This study investigates the effects of fermentation conditions on the production of angiotensin‐converting enzyme inhibitory (ACE‐I) peptides in yogurt by Lactobacillus helveticus 881315 (L. helveticus) in the presence or absence of Flavourzyme®, which is derived from a mould, Aspergillus oryzae and used for protein hydrolysis in various industrial applications. Optimal conditions for peptides with the highest ACE‐I activity were 4% (v/w) inoculum size for 8 h without Flavourzyme® supplementation, and 1% inoculum size for 12 h when combined with Flavourzyme®. The yogurt fermented by L. helveticus resulted in IC50 values (concentration of inhibitor required to inhibit 50% of ACE activity under the assayed conditions) of 1.47 ± 0.04 and 16.91 ± 0.25 mg mL?1 with and without Flavourzyme® respectively. Seven fractions of ACE‐I peptides from the yogurt incorporated with L. helveticus and Flavourzyme® were separated using the preparative high‐performance liquid chromatography. Fraction (F3) showed the highest ACE‐I activity with an IC50 of 35.75 ± 5.48 μg mL?1. This study indicates that yogurt may be a valuable source of ACE‐I peptides, which may explain the outcomes observed in the experimental and clinical studies and foresee the application of fermented milk proteins into functional foods or dietary supplements.  相似文献   

2.
Angiotensin‐converting enzyme inhibitory (ACE‐I) activity as affected by Lactobacillus helveticus strains (881315, 881188, 880474, and 880953), and supplementation with a proteolytic enzyme was studied. Reconstituted skim milk (12% RSM) or whey protein concentrate (4% WPC), with and without Flavourzyme® (0.14% w/w), were fermented with 4 different L. helveticus strains at 37 °C for 0, 4, 8, and 12 h. Proteolytic and in vitro ACE‐I activities, and growth were significantly affected (P < 0.05) by strains, media, and with enzyme supplementation. RSM supported higher growth and produced higher proteolysis and ACE‐I compared to WPC without enzyme supplementation. The strains L. helveticus 881315 and 881188 were able to increase ACE‐I to >80% after 8 h of fermentation when combined with Flavourzyme® in RSM compared to the same strains without enzyme supplementation. Supplementation of media by Flavourzyme® was beneficial in increasing ACE‐I peptides in both media. The best media to release more ACE‐I peptides was RSM with enzyme supplementation. The L. helveticus 881315 outperformed all strains as indicated by highest proteolytic and ACE‐I activities.  相似文献   

3.
PurposeTo investigate the effect of the addition of electrolytes, basic tear solution (BTS), and sodium carboxymethylcellulose (SCMS) on the tear ferning (TF) patterns of Blink Contact Soothing Eye Drops® and Refresh Plus Tears®.MethodSamples of Blink Contact Soothing Eye Drops® and Refresh Plus Tears® (10 μL) were mixed with different volumes (3–30 μL) of several electrolytes, namely sodium chloride, potassium chloride, calcium chloride, magnesium chloride hexahydrate, sodium hydrogen carbonate, and sodium dihydrogen phosphate, BTS, and SCMS. Samples (1 μL) of the mixtures were dried on a glass slide at room temperature and the TF patterns were inspected using a light microscope, graded using the Masmali five-point grading scale and compared to the corresponding TF grades of the artificial tears.ResultsThe TF grades of Blink Contact Soothing Eye Drops® and Refresh Plus Tears® improved from 1.2 and 1.5, respectively to 0.2 when calcium chloride was used as the electrolyte. Improvements in TF grades were also observed when other electrolytes (e.g., sodium dihydrogen phosphate), BTS, and SCMS were used.ConclusionThe tear ferning test can be used to evaluate the effect of the addition of electrolytes to an artificial tear in-vitro. The TF patterns of artificial tear solutions such as Blink Contact Soothing Eye Drops® and Refresh Plus Tears® can be improved with the addition of various concentrations of electrolytes, BTS, and SCMS, however further research is still needed to understand the clinical relevance of TF patterns with respect to the management of dry eye symptoms and their potential role in the development of new artificial tears.  相似文献   

4.
β‐Carotene, zeaxanthin, lutein, β‐cryptoxanthin, and lycopene are liposoluble pigments widely distributed in vegetables and fruits and, after ingestion, these compounds are usually detected in human blood plasma. In this study, we evaluated their potential to inhibit hemolysis of human erythrocytes, as mediated by the toxicity of peroxyl radicals (ROO?). Thus, 2,2′‐azobis (2‐methylpropionamidine) dihydrochloride (AAPH) was used as ROO? generator and the hemolysis assay was carried out in experimental conditions optimized by response surface methodology, and successfully adapted to microplate assay. The optimized conditions were verified at 30 × 106 cells/mL, 17 mM of AAPH for 3 h, at which 48 ± 5% of hemolysis was achieved in freshly isolated erythrocytes. Among the tested carotenoids, lycopene (IC50 = 0.24 ± 0.05 μM) was the most efficient to prevent the hemolysis, followed by β‐carotene (0.32 ± 0.02 μM), lutein (0.38 ± 0.02 μM), and zeaxanthin (0.43 ± 0.02 μM). These carotenoids were at least 5 times more effective than quercetin, trolox, and ascorbic acid (positive controls). β‐Cryptoxanthin did not present any erythroprotective effect, but rather induced a hemolytic effect at the highest tested concentration (3 μM). These results suggest that selected carotenoids may have potential to act as important erythroprotective agents by preventing ROO?‐induced toxicity in human erythrocytes.  相似文献   

5.
A randomized, double‐blinded, placebo‐controlled and crossover study was conducted to simultaneously measure the effects, 3 h after consumption and after 4‐wk daily exposure to plant sterols‐enriched food product, on in vivo nitrite and nitrate production in healthy adults. Eighteen healthy participants (67% female, 35.3 [mean] ± 9.5 [SD] years, mean body mass index 22.8 kg/m2) received 2 soy milk (20 g) treatments daily: placebo and one containing 2.0 g free plant sterols equivalent of their palmityl esters (β‐sitosterol, 55%; campesterol, 29%; and stigmasterol, 23%). Nitrite and nitrate concentrations were measured in the blood plasma and urine, using stable isotope‐labeled gas chromatography‐mass spectrometry. L‐arginine and asymmetric dimethylarginine concentrations in blood serum were measured using commercially available enzyme immunoassays. Nitrite and nitrate concentrations in blood plasma (nitrite 5.83 ± 0.50 vs. 4.52 ± 0.27; nitrate 15.78 ± 0.96 vs. 13.43 ± 0.81 μmol/L) and urine (nitrite 1.12 ± 0.22 vs. 0.92 ± 0.36, nitrate 12.23 ± 1.15 vs. 9.71 ± 2.04 μmol/L) were significantly elevated after 4‐wk plant sterols supplementation Placebo and 3‐h treatments did not affect the blood plasma and urinary concentrations of nitrite and nitrate. Circulating levels of L‐arginine and asymmetric dimethylarginine were unchanged in the placebo and treatment arms. Total plant sterols, β‐Sitosterol, campesterol, and stigmasterol concentrations were significantly elevated after 4‐wk treatments compared to the placebo and 3‐h treatments. Blood plasma nitrite and nitrate concentrations correlated significantly with the plasma total and specific plant sterol concentrations. Our results suggest that dietary plant sterols, in the combination used, can upregulate nitrite, and nitrate production in vivo.  相似文献   

6.
目的:以苦荞提取物为研究对象,通过正交实验设计优化苦荞提取物中芦丁被酸水解为槲皮素的工艺条件,并结合药代动力学研究探讨酸水解工艺对苦荞提取物中芦丁和槲皮素吸收的影响。方法:以盐酸百分含量、水解时间、乙醇百分含量、水解温度作为因素设计四因素三水平正交实验优化苦荞提取物中芦丁酸水解为槲皮素的工艺条件,以该工艺进行苦荞提取物酸水解,并在水解第1、2、4、6 h取样得到不同槲皮素含量的水解产物1、2、3、4。分别灌胃大鼠200 mg/kg的苦荞提取物及各水解产物,并在不同时间点采血,以黄芩素为内标,高效液相色谱(HPLC)测定血浆中槲皮素的浓度,DAS 2.0计算主要药代动力学参数。结果:苦荞提取物芦丁酸水解的最佳工艺参数为盐酸百分含量0.91%、水解时间6 h、乙醇百分含量50%、水解温度70 ℃,在该工艺条件下64.11%芦丁转化为槲皮素。苦荞提取物、水解产物1、2、3、4槲皮素的AUC0-t分别为(17.604±5.422)、(42.175±9.435)、(87.917±19.347)、(116.706±46.256)、(178.509±49.478) mg/L·h,Cmax分别为(2.743±1.217)、(7.109±2.603)、(12.438±3.197)、(15.727±4.68)、(20.044±5.736) mg/L。与苦荞提取物相比,其水解产物1、2、3、4的药代动力学参数AUC0-t、Cmax具有显著性差异(p<0.05)。结论:苦荞提取物经酸水解后部分芦丁转化为槲皮素,芦丁和槲皮素在大鼠体内的累计吸收量也相应提高。  相似文献   

7.
The optimisation of the spray drying process for low‐phenylalanine skim milk as a dietary supplement for phenylketonurics was studied. The effects of basic parameters including the inlet air temperature (100, 150 and 200 °C), feed flow rate (5, 10 and 15 mL min?1) and air flow rate (400, 600 and 800 L h?1) on the solubility and particle size of the low‐phenylalanine skim milk powder were determined using response surface methodology. The optimum conditions have been obtained with inlet air temperature of 133 °C, feed flow rate of 5 mL min?1, and air flow rate of 800 L h?1. With the optimum parameters, the predicted values for the solubility and mean diameter were 95.33% and 5.34 μm, respectively, and experimentally were 94.36 ± 1.62% and 5.50 ± 0.44 μm, respectively. The experimental and predictive values were closely related showing predictive accuracy of the models.  相似文献   

8.
Scope Xanthohumol (XN), a dietary flavonoid found in hops, may have health‐protective actions against cardiovascular disease and type 2 diabetes. Yet, there are limited data on the pharmacokinetics (PK) of XN. This study provides PK parameters for XN and its major metabolites in rats. Methods and results A PK study was conducted in male jugular vein‐cannulated Sprague‐Dawley rats. Rats (n = 12/group) received an intravenous (IV) injection (1.86 mg/kg BW) or an oral gavage of a low (1.86 mg/kg BW), medium (5.64 mg/kg BW), or high (16.9 mg/kg BW) dose of XN. Plasma samples were analyzed for XN and its metabolites using LC‐MS/MS. The maximum concentration (Cmax) and area under the curve (AUC0‐96 h) of total XN (free and conjugated) were 2.9±0.1 mg/L and 2.5±0.3 h* mg/L in IV group, 0.019±0.002 mg/L and 0.84±0.17 h* mg/L in the oral low group, 0.043±0.002 mg/L and 1.03±0.12 h* mg/L in the oral medium group, and 0.15±0.01 mg/L and 2.49±0.10 h* mg/L in the oral high group. Conclusion The bioavailability of XN is dose‐dependent and approximately 0.33, 0.13, and 0.11 in rats, for the low‐, medium‐, and high‐dose groups, respectively.  相似文献   

9.
A simple in vitro assay for the determination of soluble iron in fortified rice analogue/natural rice blends is described. The soluble iron, measured as an indicator of iron bioavailability, is quantified by FerroZine? colorimetry of the supernatant obtained after simulated gastric (pepsin) and intestinal (pancreatin) digestions. Method suitability was defined by assessments of linearity (R 2 average=0.9999±0.0001, and low standard residual average=+0.6±0.9 %; n=17), precision (day-to-day RSD values [n=3 days] ranged from 5.3 % to 75 % for concentrations from 0.017 to 0.585 mg per 100 g of fortified rice analogue/natural rice blend), accuracy (spike recovery=97.5±0.4 %, n=4, spiking level=0.2 to 0.8 mg/l; and linear response of the digest plot [R 2=1.0000] vs. the standard solution plot [R 2=1.0000]), and selectivity (absence of interference from Ca, Mg, Mn, and Zn; reagent blank correction for minimal bias by Cu). The assay provides for a reliable quantification of the soluble iron in fortified rice analogue/natural rice blends. The assay is regarded not as a substitute for in vivo determination of iron absorption, but instead as a tool for identifying formulation, extrusion, and storage issues that are worthy of formal in vivo study. In this connection, application of the assay to fortified rice analogue/natural rice blends and to experimental rice flour preparations has identified potential agents of iron absorption enhancement (e.g., NaFeEDTA at only 2 % of total iron), and of iron absorption inhibition (zinc).  相似文献   

10.
The addition of NaFeEDTA at only 5% of total iron to ferric pyrophosphate‐fortified Ultra Rice® increased the in vitro soluble iron ten‐fold. Ultra Rice® formulated with NaFeEDTA at 2–7% of total iron, or with Na2EDTA·2H2O at 0.5× the total iron equivalents, increased the soluble iron seven‐ to thirty‐fold. The colour of the batches was acceptable through 20 weeks at 21 °C, but colour stability needs to be evaluated under authentic storage conditions. Although only 34–46% of the initial vitamin A remained after extrusion, 18‐week storage at 30 °C/70% relative humidity, and simulated cooking, there were indications that losses could be decreased by raising the pH (to ~5) and/or using a better protected vitamin A ingredient. The enhancement of soluble iron afforded by low‐level NaFeEDTA or Na2EDTA·2H2O supplementation suggests that this fortification strategy may merit further study as a means of increasing absorbable iron in Ultra Rice®.  相似文献   

11.
In this study, antioxidant and antihemolytic activities of ethanolic extract of flowers, leaves, and stems of Hyssopus officinalis L. Var. angustifolius were investigated employing different in vitro assay systems. Extracts showed good antioxidant activity. IC50 for 1,1-diphenyl-2-picryl hydrazyl radical-scavenging activity were 148.8 ± 4.31 μg mL?1 for flowers, 79.9 ± 2.63 μg mL?1 for stems, and 208.2 ± 6.45 μg mL?1 for leaves. All extracts showed moderate iron (II) chelating ability. Extracts exhibited good antioxidant activity in the hemoglobin-induced linoleic acid model and also they were capable of scavenging hydrogen peroxide in a concentration dependent manner. Extracts showed good antihemolytic activity againts hydrogen peroxide-induced hemolysis (IC50 were 48.51 ± 2.27 μg mL?1 for flowers, 19.47 ± 0.73 μg mL?1 for leaves, and 63.1 ± 2.65 μg mL?1 for stems). The total amount of phenolic compounds in the extracts was determined as gallic acid equivalents and total flavonoid content was calculated as quercetin equivalents from a calibration curve.  相似文献   

12.
Plant‐based diets contain less saturated fat and cholesterol and more folate, fibre and phytochemicals than omnivorous diets, but some micronutrients, especially zinc, are poorly bioavailable. The findings of studies exploring the zinc intake and zinc status in populations that habitually consume vegetarian diets are inconsistent. This study aims to investigate the effects of plant‐based diets on dietary zinc intake and status in humans using systematic review and meta‐analysis techniques. Thirty‐four studies were included in the systematic review. Of these, 26 studies (reporting 48 comparisons) compared males and/or females consuming vegetarian diets with non‐vegetarian groups and were included in meta‐analyses. Dietary zinc intakes and serum zinc concentrations were significantly lower (?0.88 ± 0.15 mg day?1, P < 0.001 and ?0.93 ± 0.27 µmol L?1, P = 0.001 respectively; mean ± standard error) in populations that followed habitual vegetarian diets compared with non‐vegetarians. Secondary analyses showed greater impact of vegetarian diets on the zinc intake and status of females, vegetarians from developing countries and vegans. Populations that habitually consume vegetarian diets have low zinc intakes and status. Not all vegetarian categories impact zinc status to the same extent, but a lack of consistency in defining vegetarian diets for research purposes makes dietary assessment difficult. Dietary practices that increase zinc bioavailability, the consumption of foods fortified with zinc or low‐dose supplementation are strategies that should be considered for improving the zinc status of vegetarians with low zinc intakes or serum zinc concentrations at the lower end of the reference range. © 2013 Society of Chemical Industry  相似文献   

13.
The objectives of the current study were to determine S‐methyl‐L‐methionine (SMM) from various Brassicaceae family vegetables by using validated analytical method and to characterize the intestinal transport mechanism of SMM by the Caco‐2 cells. The SMM is well known to provide therapeutic activity in peptic ulcers. The amount of SMM from various Brassicaceae family vegetables ranged from 89.08 ± 1.68 μg/g to 535.98 ± 4.85 μg/g of dry weight by using validated ultra‐performance liquid chromatography‐electrospray ionization‐mass spectrometry method. For elucidating intestinal transport mechanism, the cells were incubated with or without transport inhibitors, energy source, or a metabolic inhibitor. Phloridzin and verapamil as inhibitors of sodium glucose transport protein (SGLT1) and P‐glycoprotein, respectively, were not responsible for cellular uptake of SMM. Glucose and sodium azide were not affected by the cellular accumulation of SMM. The efflux ratio of SMM was 0.26, implying that it is not effluxed through Caco‐2 cells. The apparent coefficient permeability (P app) of SMM was 4.69 × 10?5 cm/s, indicating that it will show good oral absorption in in vivo .  相似文献   

14.
Apples (Malus domestica L.) are the most common source of phenolic compounds in northern European diet. Besides pectins, dietary fibers, vitamins, and oligosaccharides they contain phenolic compounds of different classes. Apple powders are convenient functional forms retaining significant amounts of phenolic antioxidants. In this study reducing and radical scavenging profiles of freeze‐dried powders of “Aldas,? “Auksis,? “Connel Red,? “Ligol,? “Lodel,? and “Rajka? were determined and phenolic constituents were identified using ultra high‐performance liquid chromatography coupled to quadrupole and time‐of‐flight mass spectrometers. A negative ionization mode was applied and seventeen compounds: phenolic acids (coumaroylquinic, chlorogenic), flavonoids (quercetin derivatives), and procyanidin derivatives (B1, B2, and C1) were identified in all tested apple samples. Total values of Trolox equivalents varied from 7.72 ± 0.32 up to 20.02 ± 0.52 and from 11.10 ± 0.57 up to 21.42 ± 0.75 μmol/g of dry weight of apple powder in FRAP (ferric reducing antioxidant power) and ABTS (2,2‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) postcolumn assays, respectively. The greatest Trolox equivalent values were determined for apples of “Aldas? cultivar. Chlorogenic acid and procyanidin C1 were the most significant contributors to total reducing and radical scavenging activity in all apple cultivars tested, therefore they could be considered as markers of antioxidant activity.  相似文献   

15.
This study was carried out to examine the proteolytic and angiotensin‐converting enzyme (ACE‐I) activities of probiotic lactic acid bacteria (LAB) as influenced by the type of media, fermentation time, strain type and media supplementation with a proteolytic enzyme (Flavourzyme®). Lactobacillus casei (Lc210), Bifidobacterium animalis ssp12 (Bb12), Lactobacillus delbrueckii subsp. bulgaricus (Lb11842) and Lactobacillus acidophilus (La2410) were grown in 12% of reconstituted skim milk (RSM) or 4% of whey protein concentrates (WPC‐35) with or without combination (0.14%) of Flavourzyme® for 12 h at 37 °C. All the strains were able to grow in both media depending on type of strains used and fermentation time. All the strains showed higher proteolytic activity and produced more antihypersensitive peptides when grown in RSM medium at 12 h, when compared to WPC. Combination with Flavourzyme® also increased LAB growth and proteolytic and ACE‐I activities. Of the four strains used, Bb12 and La2410 outperformed Lc210 and Lb11842. The highest ACE‐I activity and proteolytic activity were found in B. animalis ssp12 combined with Flavourzyme®. Flavourzyme® led to an increase in the production of bioactive peptides with ACE‐I activity during 12 h at 37 °C.  相似文献   

16.
Date (Pheonix dactylifera L.) seeds are a valuable and abundant by‐product with various potential food applications. Free polyphenols (FPPs) and bound polyphenols (BPPs) of date seeds from Deglet Nour variety grown in Australia were investigated using high‐performance liquid chromatography‐mass spectrometry. The FPP fraction contained the following main phenolic compounds per gram of date seed powder; procyanidin B1 (499.8 ± 7.8 μg), procyanidin B2 (288.6 ± 6.1 μg), catechin (167.6 ± 2.1 μg), epicatechin (39.44 ± 0.39 μg), and protocatechuic acid (1.77 ± 0.22 μg). Additionally, one of the 2 A‐type dimers was confirmed as procyanidin A2 (24.05 ± 0.12 μg/g). A‐type dimers have not been reported before in date seeds. The BPP fraction contained epicatechin (52.59 ± 0.76 μg/g) and procyanidin B2 (294.2 ± 3.7 μg/g), while several peaks exhibiting ESI? m/z of 153 indicated dihydroxybenzoic acid isomers including protocatechuic acid (2.138 ± 0.025 μg/g). These findings contributed to our knowledge of date seed phytochemicals and understanding of their contribution to the reported bioactivities.  相似文献   

17.
《Journal of dairy science》2023,106(7):5054-5073
The objectives of this study were to evaluate how varying colostral insulin concentrations influenced small intestinal development and peripheral metabolism in neonatal Holstein bulls. Insulin was supplemented to approximately 5× (70.0 μg/L; n = 16) or 10× (149.7 μg/L; n = 16) the basal colostrum insulin (12.9 μg/L; BI, n = 16) concentration to maintain equivalent macronutrient intake (crude fat: 4.1 ± 0.06%; crude protein: 11.7 ± 0.05%; and lactose: 1.9 ± 0.01%) among treatments. Colostrum was fed at 2, 14, and 26 h postnatal and blood metabolites and insulin concentration were measured at 0, 30, 60, 90, 120, 180, 240, 360, 480, and 600 min postprandial respective to the first and second colostrum meal. At 30 h postnatal, a subset of calves (n = 8/treatment) were killed to excise the gastrointestinal and visceral tissues. Gastrointestinal and visceral gross morphology and dry matter and small intestinal histomorphology, gene expression, and carbohydrase activity were assessed. Insulin supplementation tended to linearly reduce the glucose clearance rate following the first meal, whereas after the second meal, supplementation linearly increased the rate of glucose absorption and nonesterified fatty acid clearance rate, decreased the time to maximum glucose concentrations, and decreased the time to reach minimum nonesterified fatty acid concentrations. Additionally, insulin clearance rate was linearly increased by insulin supplementation following the second colostrum feeding. However, there were no overall differences between treatments in the concentrations of glucose, nonesterified fatty acids, or insulin in plasma or serum. With respect to macroscopic intestinal development, dry rumen tissue mass linearly decreased when insulin was supplemented in colostrum, and supplementation linearly increased duodenal dry tissue density (g dry matter/cm) while tending to increase duodenal dry tissue weight. Increasing the colostrum insulin concentration improved small intestinal histomorphological development in the distal small intestine, as ileal villi height and mucosal-serosal surface area index were increased by supplementing insulin. Lactase enzymatic activity linearly increased in the proximal jejunum while ileal isomaltase activity linearly decreased with insulin supplementation. These data indicate that changes in colostrum insulin concentrations rapidly affect gastrointestinal growth prioritization and carbohydrase activity. The changes in gastrointestinal ontology result in minor changes in postprandial metabolite availability and clearance.  相似文献   

18.
BACKGROUND: The paper discusses biosorption of microelements by a freshwater macroalga Pithophora varia Wille to produce biological feed supplement for livestock. The biomass was enriched with microelements recommended by feeding standards in a single and a multi‐metal system. RESULTS: The equilibrium of biosorption was described by using a Langmuir model and the following values of the maximum biosorption capacity in the single‐metal system were obtained: Zn(II), 61.1 mg g?1; Co(II), 52.3 mg g?1; Cu(II), 55.7 mg g?1; and Mn(II), 38.3 mg g?1. The average value of maximum biosorption capacity expressed in molar units for all the cations was equal 1.7 ± 0.2 meq g?1, suggesting chemical rather than physical biosorption. It was also found that the mechanism of biosorption was due to cation exchange of alkali and alkaline earth metals with microelements. The biomass was also enriched with microelements in multi‐metal system. The total metal ion binding capacity in the multi‐metal system was two‐fold lower than in the single‐metal system and was 0.90 meq g?1 in the preparation for laying hens and 0.95 meq g?1 in the supplement for swine. CONCLUSION: Finally, the level of supplementation of livestock feed (with enriched single‐ and multi‐metal system macroalga), to cover 25% of total requirements for microelements, according to feeding standards, was provided. Copyright © 2008 Society of Chemical Industry  相似文献   

19.

Scope

We modeled red blood cell (RBC)‐folate response to supplementation and developed personalized folate supplementation concepts.

Methods and results

The changes of RBC‐folate were modeled in a time‐ (4 or 8 weeks) and dose‐ (400 or 800 μg d?1 folate) dependent manner. Post‐supplementation RBC‐folate levels were predicted from folate‐loading capacities (= measured RBC‐folate – [baseline RBC‐folate × RBC‐survival]). The prediction equations were validated in 119 participants. The median increase of RBC‐folate was higher in the 800 μg d?1 than in the 400 μg d?1 group (275 vs 169 nmol L?1 after 4 weeks, and 551 vs 346 nmol L?1 after 8 weeks). Medians (interquartile range) of RBC‐folate loading were (4 weeks: 299 (160) vs 409 (237) nmol L?1) and (8 weeks: 630 (134) versus 795 (187) nmol L?1) in the 400 and 800 μg d?1 group, respectively. The individual measured and predicted RBC‐folate values (after 4 weeks/400 μg d?1 = 25 + 1.27 × baseline RBC‐folate) and (after 4 weeks/800 μg d?1 = 65 + 1.41 × baseline RBC‐folate) did not differ significantly. The measured and predicted concentrations showed high agreement in the validation cohort.

Conclusions

The models can guide nutritional recommendations in women when baseline RBC‐folate concentrations are measured and the time to pregnancy between 4 and 8 weeks.
  相似文献   

20.
In this study, we have explored the relationship between the cultivation method and the concentration of major flavonoid aglycones, hydroxycinnamic acids, carotenoids and the total antioxidant activity of tomato (Lycopersicon esculentum cv Perfectpeel); in addition, we have investigated the bioactivity of polyphenol extracts from tomato. The main polyphenols in extracts were quercetin (33.90 ± 6.31 mg kg?1 and 17.92 ± 1.09 mg kg?1 in conventional and organic extracts), chlorogenic acid (3.52 ± 0.74 mg kg?1 and 2.82 ± 0.92 mg kg?1 in conventional and organic extracts) and caffeic acid (3.61 ± 0.71 mg kg?1 and 3.29 ± 0.33 mg kg?1 in conventional and organic extracts). Although statistical differences were found between organic and conventional extracts in several target compounds, no difference in biological effect was observed using cell models. The observed Trans Epithelial Electrical Resistance values were not significantly different between organic and conventional tomato extracts, but we have observed, in both samples, a decrease in tight‐junction permeability at 17 μm of polyphenol concentrations. Antioxidant compounds entering within the cell could exert an antioxidant action, nevertheless at concentrations >17 μm could have a pro‐oxidant effect.  相似文献   

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