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1.
Some studies suggest that increased consumption of soy protein hydrolysates may cause body weight loss but the mechanism of action is unknown. The objective of this investigation was to determine whether intracerebroventricular (i.c.v.) infusion of soy protein hydrolysates decrease food intake and body weight. Adult male Sprague Dawley rats (n = 24) received i.c.v. injections of soy hydrolysate I (SH I) or soy hydrolysate II (SH II) three times weekly for 2 weeks. Krebs solution and leptin were used as negative and positive controls respectively. SH I (6.5–20 kDa with a strong band at 14 kDa) was produced by hydrolysis with alcalase, and SH II (∼2 kDa) was obtained by hydrolysis and ultrafiltration. Leptin successfully reduced body weight (−1.60 g) 24 h (p = 0.0093) after the third injection. SH I caused significant (p = 0.0009) decreases in body weight (−1.70 g) 24 h after the third injection but not after 48 h. SH II showed a tendency to prevent body weight gain but this effect was short of statistical significance (p < 0.40). Food intake was not affected by any of the soy hydrolysate treatments but leptin injection did cause significant decreases in food intake (p < 0.05). Data suggest that soy alcalase hydrolysate can decrease, in the short term, the rate of body weight gain independently of food consumption. This preliminary data show that soy peptides may play a role on body weight regulation, possibly by increasing energy utilization.  相似文献   

2.
Germination of soybeans increases the bioavailability of some nutrients. An evaluation was done to determine if germination increased the anti-adipogenic and lipolytic effects of soybean. Soybeans were germinated for 0 to 6 days and protein concentrates extracted from beans germinated at each period. Soy protein concentrates can retain notable amounts of phytochemicals with anti-adipogenic activity. For this reason, it was evaluated the effect of protein hydrolysates with and without phytochemicals in the adipocyte-like cells after 3T3-L1 (murine fibroblasts) cell line differentiation. Cell viability decreased with exposure to the germinated soybean protein hydrolysates during the differentiation stage, but not during the fibroblast or mature adipocyte stages. Adipogenesis and triglycerides accumulation were strongly inhibited by the hydrolysate from soybeans germinated for 2 days (with ethanol-soluble phytochemicals), when compared to ungerminated soybean. Adipolysis increased with exposure to hydrolysates from beans germinated for 2 days (with phytochemicals) and 5 days (without phytochemicals). Germinated soy protein hydrolysates had an effect on inhibition of lipid storage in adypocites and increasing lipolysis, which was improved by changes of the protein and increased phytochemical content due to germination.  相似文献   

3.
The objectives of this study were to: i) define the optimum concentration of triticale bran (TB) that can be incorporated in yogurt, ii) evaluate the prebiotic effects of TB on microbial viability, pH and total titratable acidity (TTA) in yogurt across 28 days of cold storage, and iii) measure the oxygen radical absorbance capacity (ORAC) of water-extractable polysaccharides (WEP) in TB. Lactobacillus bulgaricus and Streptococcus thermophilus were used as starter cultures. Lactobacillus acidophilus and Bifidobacterium lactis were used as probiotics. A concentration of 4% TB in yogurt was determined to be the maximum amount that could be added without causing synersis. By day 7, the number of bacteria greatly increased in yogurt samples containing TB and maintained higher viable bacteria counts at the end of the cold storage period, in comparison to controls (P ≤ 0.05). Confirming this data was the lower pH levels and higher TTA values of TB yogurt samples exhibited throughout 28 days (P ≤ 0.05). Polysaccharide extracts of TB exhibited strong antioxidant activity with an ORAC value of 33.86 ± 2.30 μmol trolox equivalents (TE)/g of bran. Results of this study suggest that TB may serve as a new prebiotic and antioxidant source for functional foods and nutraceutical applications.  相似文献   

4.
The aim of this study was to evaluate the protein quality of organic and genetically modified soy by feeding specific diets to rats. Three groups of Wistar rats (n = 10) were used, and each group was named according to the food that they ate. There was an organic soy group (OG), a genetically modified soy group (GG), and a control group (CG). All animals received water and diet ad libitum for 455 days. At the end of this period, the weight of the GG group was the same as that of the OG, and both were higher than CG. Protein intake was similar for the OG and GG, which were significantly lower (p < 0.0005) than the CG. The growth rate (GR) of the rats, albumin levels, and total levels of serum protein were comparable for all groups. Hematocrit (p < 0.04) and hemoglobin (p < 0.03) for the OG and GG were less than the CG. Although the OG and GG demonstrated reduced hematocrit and hemoglobin, both types of soy were utilized in a way similar to casein. This result suggests that the protein quality of soy is parallel to the standard protein casein in terms of growth promotion but not hematological indicators.  相似文献   

5.
Previous short-term trials (9-week duration) have shown that the fry colour of stored potatoes (Solanum tuberosum L.) can be negatively affected by simultaneous exposure to elevated CO2 plus a trace concentration of ethylene gas. In the present study, trials were conducted during each of two storage seasons (2008–2009 and 2009–2010), to examine the effects of long-term exposure to these two gases during the entire November to June storage season. In each year, 0 or 2 kPa CO2 and 0 or 0.5 μl l−1 ethylene were applied in a factorial design to tubers of four processing cultivars (Russet Burbank, Shepody, Innovator and Dakota Pearl). Processing colour of the tubers was evaluated at the start of each trial and at intervals of 4 weeks thereafter. In the three French fry cultivars (i.e. Russet Burbank, Shepody and Innovator), the fry colour of tubers exposed to CO2 + ethylene together was darker than the controls. In the chipping cultivar Dakota Pearl, the gas treatments had only a small effect on chip colour. Fry colour darkening due to an interaction of CO2 × ethylene × time was significant only in Innovator. Processing colour of all cultivars was darkened by these gases, but the magnitude and timing of the responses varied widely between gases, among cultivars and from the start to the end of the season.  相似文献   

6.
Hordein, the major storage protein of barley (Hordeum vulgare L.), was hydrolysed by three selected proteases, including alcalase, flavourzyme and pepsin. The effects of protease type and hydrolysis time on hordein molecular weight, surface hydrophobicity, secondary structure and antioxidant activity were investigated. Flavourzyme hydrolysis of hordein was relatively more extensive and rapid, resulting in the formation of medium- and small-sized peptides with a broad distribution within 30 min. Alcalase and pepsin more gradually and less extensively hydrolysed hordein into medium- and larger-sized peptides, respectively. Protein surface hydrophobicity decreased with an increasing degree of hydrolysis. The flavourzyme and alcalase hydrolysates had superior DPPH (1,1-diphenyl-2-picryl hydrazyl) free radical scavenging activity (44-70 and 48-58%, respectively, at 0.5 mg/mL), Fe2+-chelating ability (21-64% and 39-73%, respectively, at 1 mg/mL), and superoxide radical scavenging capacity. It is proposed that the large- and medium-size hydrolysate fractions were most likely responsible for the antioxidant activities of hordein hydrolysates, and could be used as antioxidant peptides in food and nutraceutical applications.  相似文献   

7.
Lupin protein is capable of reducing plasma lipids in hypercholesterolemic man and animals. Whether lipid-lowering properties of lupin protein will be influenced by thermal treatment or by other nutrients has not been elucidated. In a two-factorial study, rats were fed hypercholesterolemic diets based on high amounts of carbohydrates (HC) or fat (HF), which contained either (20.4% of energy) untreated or thermally treated lupin protein (steam: 120 °C, 30 min) or casein as control protein. Lupin protein lowered plasma lipid concentrations in rats fed the HF diet but not in those fed the HC diet (P < 0.05). Among rats fed the HF diet, plasma and VLDL triglyceride concentrations were lower in rats fed thermally treated (−46% and −44%, P < 0.05) and untreated lupin protein (−47% and −46%, P < 0.05) than in those fed casein; whereas liver triglycerides were reduced only in rats fed untreated lupin protein (P < 0.05). Compared to casein, untreated lupin protein had slightly stronger cholesterol-lowering effects in plasma, LDL and HDL (−34%, −37%, −35%; P < 0.05) than thermally treated lupin protein (−23%, −29%, −31%, P < 0.10). In conclusion, the lipid-lowering effect of lupin protein strongly depends on composition of the basal diet, and thermal treatment is accompanied by a slight reduction of its hypocholesterolemic properties.  相似文献   

8.
In Thailand, beverages containing mulberry leaf (Morus alba L.) are believed to promote good health, especially in people with diabetes. We examined the effects of long-term administration of an ethanolic extract of mulberry leaf (MA) on blood glucose, oxidative damage, and glycation in streptozotocin-induced diabetic rats. Daily administration of 1 g/kg MA for six weeks decreased blood glucose by 22%, which was comparable to the effect of 4 U/kg insulin. Lipid peroxidation, measured as malondialdehyde and lipid hydroperoxide concentrations (3.50 ± 0.33 and 3.76 ± 0.18 μM, respectively) decreased significantly (P < 0.05) compared to nontreated control diabetic rats (8.19 ± 0.45 and 7.50 ± 0.46 μM, respectively). Hemoglobin A1C, a biomarker for chronic exposure to high concentration of glucose, was also significantly decreased in the MA-treated group (6.78 ± 0.30%) in comparison to untreated group (9.02 ± 0.30%). The IC50 of in vitro antiglycation and free radical scavenging activities of MA were 16.4 ± 5.6 μg/ml and 61.7 ± 2.1 μg/ml, respectively. These findings support that long-term administration of MA has antihyperglycemic, antioxidant and antiglycation effects in chronic diabetic rats, which may be beneficial as food supplement for diabetics.  相似文献   

9.
The aim of the study was to determine whether phenolic compounds in some varieties of buckwheat, winter and spring barley and peas can be used as factors which distinguish selected cultivars and varieties of plant material. It was observed that the content of total phenolics might be useful as a cultivar-distinguishing factor for all the plant materials analyzed, but it was a distinguishing factor for only some varieties. Individual cultivars and varieties were best distinguished by the content of syringic acid. The levels of syringic and vanillic acids were in reverse proportion to the total amount of phenolics soluble in methanol and a positive correlation between syringic and ferulic acid was observed. Moreover, the protein content of plant material was analyzed and a significant (p ≤ 0.05) correlation between this component and ferulic and vanillic acids was noted.  相似文献   

10.
Muskmelons (Cucumis melo L.) are well-known as excellent sources of several vitamins, minerals and non-enzymatic antioxidant phytochemicals such as vitamin C and pro-vitamin A. Less well-studied is their potential role as sources of enzymatic antioxidants such as superoxide dismutase (SOD), which have been associated with enhanced reactive oxygen species scavenging capacity in some muskmelon fruits. In this study, we investigated the variability in SOD activities among diverse advanced breeding lines and commercial muskmelon cultivars grown in two different soil types—clay or sandy loam. Specific and total SOD activities varied significantly among the genotypes (P ≤ 0.001), compared to soil type (P ≤ 0.055). Netted (cantaloupe) genotypes generally had the lowest SOD activities compared to the green- and orange-fleshed honey dew types. Casaba type fruit had average SOD activities that were ∼ 1.6-fold greater than those of honey dew types, and ∼ 9.0-fold greater than those of cantaloupe types. These data indicate there is useful genetic diversity among commercial melon varieties and in exotic genotypes that could be used to develop C. melo as a functional food with enhanced SOD content.  相似文献   

11.
Consumption of soybeans can reduce the risk of different types of cancer. Little is known about the effect of germination on the anticancer properties of soya. This study was done to determine if germination improves the anticancer properties of soybean protein through generation of amino acids or bioactive peptides. Soybean was germinated for 0, 2, 3, 4, 5, and 6 days and proteins were isolated from the seeds. Isolates with and without ethanol-soluble phytochemicals were hydrolyzed with digestive enzymes and their effect on growth in HeLa and C-33 (epidermoid cervical carcinoma) and HaCaT (non-cancerous human keratinocytes) cells were evaluated with the Alamar Blue method. Germination induced degradation of the α and α’ fractions of β-conglycinin and acid fraction of glycinin, generating low molecular weight peptides. Degrees of hydrolysis ranged from 73–77%. Hydrolysates inhibited the growth of HeLa cells and C-33 at concentrations exceeding 1.25 mg/ml. Major inhibition was observed with the hydrolysate germinated for 2 days and containing ethanolsoluble phytochemicals (IC50 2.15 and 2.27 mg/ml for HeLa and C-33, respectively). Interestingly, hydrolysate cytoxicity for normal cells was minimal in comparison to cancer cells.  相似文献   

12.
Sugar profiles of different almond and chestnut cultivars were obtained by high-performance liquid chromatography (HPLC), by means of a refractive index (RI) detector. A solid-liquid extraction procedure was used in defatted and dried samples. The chromatographic separation was achieved using a Eurospher 100-5 NH2 column using an isocratic elution with acetonitrile/water (70:30, v/v) at a flow rate of 1.0 ml/min. All the compounds were separated in 16 min. The method was optimized and proved to be reproducible and accurate. Generally, more than 95% of sugars were identified for both matrixes. Sugars profiles were quite homogeneous for almond cultivars; sucrose was the main sugar (11.46 ± 0.14 in Marcona to 22.23 ± 0.59 in Ferragnes g/100 g of dried weight), followed by raffinose (0.71 ± 0.05 in Ferraduel to 2.11 ± 0.29 in Duro Italiano), glucose (0.42 ± 0.12 in Pegarinhos two seeded to 1.47 ± 0.19 in Ferragnes) and fructose (0.11 ± 0.02 in Pegarinhos two seeded to 0.59 ± 0.05 in Gloriette). Commercial cultivars proved to have higher sucrose contents, except in the case of Marcona. Nevertheless, chestnut cultivars revealed a high heterogeneity. Sucrose was the main sugar in Aveleira (22.05 ± 1.48), Judia (23.30 ± 0.83) and Longal (9.56 ± 0.91), while glucose was slightly prevalent in Boa Ventura (6.63 ± 0.49). The observed variance could serve for inter-cultivar discrimination.  相似文献   

13.
The objective of the present study was to evaluate the effect of the bread supplemented with whole amaranth flour (0, 20 and 40%) on iron bioavailability using Caco-2 cells model. The phytate and lower myo-inositol phosphates content in in vitro bread digests were measured by high pressure liquid chromatography. The breads made with amaranth showed significant increase of soluble phytates levels (up to 1.20 μmol/g in dry matter for the 40% of substitution) in comparison with controls, which have not detectable values. A negative correlation among phytate and Fe availability was found when increased levels of amaranth. Ferritin concentration was found 2.7- and 2.0-fold higher (P < 0.05) in cultures exposed to 20% and 40% of amaranth formulated bread samples, respectively, compared to control bread. The soluble phytate/Fe molar ratio explained the whole amaranth flour-mediated inhibitory effect associated to the limitation of available Fe; however, the use up to 20% of amaranth in bread formulation appears as a promising strategy to improve the nutritional value of bread, as indicated by the ferritin concentrations quantified in cell cultures. Higher proportion of amaranth flour increased Fe concentration although there was not detected any increase in Fe uptake.  相似文献   

14.
We hypothesized that fruit ingestion provides measurable amounts of salicylic acid (SA) and produces different metabolic and inflammatory responses compared to mere fruit sugars. In a randomized-crossover study, 26 healthy subjects received a peach shake meal (PSM) (SA: 0,06 ± 0,001 mg/100 g) and a mixed sugar meal (MSM), consisting in an aqueous solution with the same sugars found in the peach shake. In order to control for the SA contribution from meals in the previous day, 16 subjects (Group 1) abstained from fruits and vegetables consumption the evening before trials, and 10 subjects (Group 2) maintained their usual diet. Circulating SA, glucose, insulin, free fatty acids, and interleukin-6 were determined. Basal SA was lower in Group 1 than in Group 2 (0.09 ± 0.02 vs. 0.30 ± 0.03 μmol/l, p < 0.001), peaked at 90 min in both groups (0.18 ± 0.01 vs. 0.38 ± 0.02 μmol/l, p < 0.01) and remained above baseline (p < 0.05) up to 3 h. Glycemia increased less after PSM at 15 min (p < 0.01) with a lower average glucose excursion (p < 0.05). Insulin peaked at 45 min with both meals but decreased less rapidly with PSM. Free fatty acids decreased more (p < 0.01), and interleukin-6 increased less (p < 0.05) with PSM. Dietary fruit intake increases the concentration of SA in vivo, and provides non-nutrients capable to modulate the inflammatory and metabolic responses to carbohydrates.  相似文献   

15.
Gluten hydrolysates were prepared by limited enzymatic hydrolysis with a protease having a chymotryptic activity in the presence or in the absence of cysteine during the dispersion phase of the process. The hydrolysates were fractionated by ultrafiltration, using two inorganic membranes with different molecular weight cut-off (MWCO), 50 kg/mol and 150 kg/mol. The retentates were enriched in hydrophobic peptides and the permeates were enriched in hydrophilic peptides. The foaming and emulsifying properties of hydrolysates, retentates and permeates were analysed at two pHs (4 and 6·5) and two salt concentrations (0·2 and 2% NaCl). Hydrolysates displayed a foaming capacity, but the foams were not stable. Permeates generated foams at pH 6·5 only, and these foams had a very short life-time. Permeates displayed no emulsifying properties. Retentates yielded foams with a good stability and were more efficient than whole hydrolysates to stabilise emulsions. They provided a strong resistance to coalescence. The functional properties of retentates were only sightly influenced by pH and ionic strength. Neither cysteine addition, which helps gluten dispersion and increases the yield of soluble hydrolysate, nor the MWCO of the ultrafiltration membranes influenced the functionality of the hydrolysate fractions.  相似文献   

16.
《Plant Production Science》2013,16(3):224-228
Abstract

Abstract : Cotton (Gossypium hirsutum L.) and soybean (Glycine max (L.) Merr.) cultivars were grown under arid (Urumqi, Xinjiang, China) and humid (Matsudo, Chiba, Japan) conditions to analyze their abilities to adapt to arid conditions in terms of transpiration, leaf movement and leaf temperature. Under the arid condition, the leaf temperature of the cotton cultivars was higher than that of the soybean cultivar and the air temperature. There was no significant difference in leaf temperature among the cotton and soybean cultivars under the humid condition. The flow rate of stem sap in the cotton cultivars under the arid condition was always higher than that in the soybean cultivar, and was largely affected by vapor pressure deficit (VPD). Under the humid condition, however, the flow rates of stem sap were lower in the cotton cultivars than in the soybean cultivars. These results indicate that cotton can avoid heat stress by the high transpiring ability possibly supported by well-developed root systems, which leads to higher drought resistance under the arid condition. Soybean would adapt to arid conditions by the combination of paraheliotropic leaf movement and reduced transpiration.  相似文献   

17.
Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise.  相似文献   

18.
Betalains are water-soluble plant pigments that are widely used as food colorants, and have a wide range of desirable biological activities, including antioxidant, anti-inflammatory, hepatoprotective, anti-cancer properties. They can be produced from various plants, notably beetroot, but betalain products obtained in this way also have some undesirable properties and are difficult to standardize. A potentially attractive alternative is to use hairy root cultures. In the study reported here, we found that betalain extracts obtained from hairy root cultures of the red beetroot B. vulgaris cv. Detroit Dark Red also had higher antioxidant activity than extracts obtained from mature beetroots: six-fold higher 2,2-dyphenyl-1-picrylhydrazyl radical scavenging ability (90.7% inhibition, EC50 = 0.11 mg, vs 14.2% inhibition, EC50 = 0.70 mg) and 3.28-fold higher oxygen radical absorbance capacity (4,100 μM TE/g dry extract, vs 1,250 μM TE/g dry extract). The high antioxidant activity of the hairy root extracts was associated with increased concentrations (more than 20-fold) of total phenolic concomitant compounds, which may have synergistic effects with betalains. The presence of 4-hydroxybenzoic acid, caffeic acid, catechin hydrate, and epicatechin were detected in both types of extract, but at different concentrations. Rutin was only present at high concentration (1.096 mg.g−1 dry extract) in betalain extracts from the hairy root cultures, whereas chlorogenic acid was only detected at measurable concentrations in extracts from intact plants.  相似文献   

19.
This study investigated whether the consumption of a diet in which high-β-glucan barley replaced rice would reduce the visceral fat area as well as the serum low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) in hypercholesterolemic Japanese men. A randomized, double-blinded, placebo-controlled intervention study was conducted in 44 hypercholesterolemic Japanese men with a body mass index (BMI) >22 kg/m2. The subjects were randomly assigned to groups consuming either rice (placebo group) or a mixture of rice and pearl barley with a high β-glucan content (test group, 7.0 g β-glucan per day) for 12 weeks. Blood samples were taken, and CT scan obtained before the trial and every four weeks during the trial. The pearl barley intake significantly reduced serum concentrations of LDL-C (P = 0.041) and TC (P = 0.037) during the trial. Significant differences between the test and placebo groups were found for the visceral fat (P = 0.039), BMI (P = 0.015), and waist circumference (P = 0.011) at the end point. The consumption of pearl barley with a high β-glucan content reduces not only LDL-C but also visceral fat area.  相似文献   

20.
Controlled environment studies with potato frequently assume responses from single-stem potato plants can be extrapolated to the field where multiple-stemmed plants are common. Controlled environment studies were conducted to characterize differences in canopy growth, development, and dry matter production between single- and multiple-stemmed potted potatoes. Leaf area distribution was influenced by stem density, with main stem and apical lateral branch leaf area being 150% to 200% larger in triple-stemmed (3S) versus single-stemmed (1S) pots (P < 0.01), while basal lateral branch leaf area was 50% less (P < 0.01). Basal lateral branches were more developed in 1S pots with longer branch lengths, more leaf area, and higher orders of branching. In a second experiment, more leaves were initiated in higher-density pots; however, individual leaf areas were approximately 50% smaller than those in 1S pots. Total leaf area and total, vegetative, and tuber dry matter production were unaffected by stem density in either experiment on a per pot basis. Development and growth of lower basal lateral branches in the 1S potato canopy offset any initial advantage in leaf numbers in the multiple-stemmed plants. These results appeared to validate the assumption that, given a late maturing cultivar and adequate nutrition, responses from single-stemmed plants can be extended to multiple-stemmed plants when expressed on a production area basis. These findings have practical considerations for potato researchers who conduct growth chamber experiments and potato modelers.  相似文献   

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