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1.
This study evaluated a novel stearic acid complexed high-amylose cornstarch (SAC) for the prevention of preneoplastic lesions in the colon of azoxymethane (AOM)-treated Fisher 344 rats fed resistant starches at 50-55% of the diet for 8 weeks. Uncooked SAC (r-SAC) diet was compared with raw normal-cornstarch diet (r-CS) or raw high-amylose cornstarch diet (r-HA), and water-boiled CS (w-CS) was compared with w-HA and w-SAC, respectively. w-SAC markedly reduced mucin-depleted foci (MDF) numbers compared with w-HA or w-CS. r-HA significantly decreased aberrant crypt foci (ACF) numbers compared with r-CS or r-SAC. Increased cecum weight and decreased cecum pH were observed in the SAC or HA groups. The highest amounts of total or individual short-chain fatty acids (SCFAs) in cecum and of butyrate or propionate in feces were observed in the AOM-treated w-SAC group. This study revealed the effectiveness of a novel resistant starch in inhibiting colonic preneoplastic lesions and the importance of high-moisture cooking on the suppression of colon carcinogenesis by this resistant starch.  相似文献   

2.
The effects of intake of dietary amounts of carrot or corresponding amounts of (-)-(3R)-falcarinol from carrots on development of azoxymethane (AOM)-induced colon preneoplastic lesions were examined in male BDIX rats. Three groups of eight AOM-treated rats were fed the standard rat feed Altromin supplemented with either 10% (w/w) freeze-dried carrots with a natural content of 35 mug falcarinol/g, 10% maize starch to which was added 35 mug falcarinol/g purified from carrots, or 10% maize starch (control). After 18 weeks, the animals were euthanized and the colon was examined for tumors and aberrant crypt foci (ACF), which were classified into four size classes. Although the number of small ACF was unaffected by the feeding treatments, the numbers of lesions as a function of increasing size class decreased significantly in the rats that received one of the two experimental treatments, as compared with the control treatment. This indicates that the dietary treatments with carrot and falcarinol delayed or retarded the development of large ACF and tumors. The present study provides a new perspective on the known epidemiological associations between high intake of carrots and reduced incidence of cancers.  相似文献   

3.
Inflammatory bowel diseases have been a risk factor of colorectal cancer (CRC). The reactive oxygen species (ROS) generated by inflammatory cells create oxidative stress and contribute to neoplastic transformation, proliferation, and even metastasis. Previously, resveratrol (RS) and pterostilbene (PS) had been reported to prevent chemical-induced colon carcinogenesis by anti-inflammatory and pro-apoptotic properties. In this study, we investigated whether RS and PS could prevent the azoxymethane (AOM)-induced colon tumorigenesis via antioxidant action and to explore possible molecular mechanisms. Male BALB/c mice were injected with AOM (5 mg/kg of body weight) with or without RS or PS, and at the end of the protocol, all of the mice were euthanized and colons were analyzed. Administrations of PS can be more effective than RS in reducing AOM-induced formation of aberrant crypt foci (ACF), lymphoid nodules (LNs), and tumors. We also find that PS is functioning more effectively than RS to reduce nuclear factor-κB (NF-κB) activation by inhibiting the phosphorylation of protein kinase C-β2 (PKC-β2) and decreasing downstream target gene expression, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and aldose reductase (AR) in mouse colon stimulated by AOM. Moreover, administration of RS and PS for 6 weeks significantly enhanced expression of antioxidant enzymes, such as heme oxygenase-1 (HO-1) and glutathione reductase (GR), via activation of NF-E2-related factor 2 (Nrf2) signaling. When the above findings are taken together, they suggest that both stilbenes block cellular inflammation and oxidative stress through induction of HO-1 and GR, thereby preventing AOM-induced colon carcinogenesis. In comparison, PS was a more potent chemopreventive agent than RS for the prevention of colon cancer. This is also the first study to demonstrate that PS is a Nrf2 inducer and AR inhibitor in the AOM-treated colon carcinogenesis model.  相似文献   

4.
Providing balanced energy and nutrients for microbiota growth is essential for the maintenance of the colon ecosystem, and dietary fiber (DF) fermentation, particularly butyrogenic fermentation, augments colon health. Cereal DF, which are the complex carbohydrates of cereal grains that escape small intestine digestion and function either as substrate for colonic fermentation or as bulking material, are a dietary measure to mitigate the occurrence of certain colonic diseases, and perhaps to some degree act as therapeutic agents. In developed Western countries, as well as in many developing countries, colon cancer is one of the major causes for premature death and disability, and inflammatory bowel disease and other colonic disorders have become serious health issues. The function of DF in colon health is mediated through its physicochemical properties (e.g., water‐holding for laxative effect) or effect on colon microbiota (e.g., leading to immune regulation), as well as through colonic fermentation products, principally the short chain fatty acids (SCFA) of acetate, propionate, and butyrate. Due to the chemical diversity and complexity of DF and because not all DF materials function equally, new developments in DF fermentation behavior (pattern and end product profile) will be reviewed from a structure‐function viewpoint. The effect of cereal DF, mainly nonstarch cereal polysaccharides and resistant starch on colonic microbiota, fermentation products of SCFA, microbiota modulation, as well as on colon health will be summarized.  相似文献   

5.
The antiradical activity of dry beans was evaluated in order to assess the validity of this test and to correlate the results with those achieved with the Folin-Ciocalteu method and with a rapid spectrophotometric method for the analysis of total flavonoids. Four landraces (12 samples) of common beans (Phaseolus vulgaris L.), collected in two regions of Italy (Tuscany and Basilicata) in three different years, were analyzed. The EC50 values ranged from 39 to 2810 mg sample/mg 1,1-diphenyl-2-picrylhydrazil radical. The phenolic content of each sample was expressed as gallic acid equivalents; it changed from 1.17 to 4.40 mg/g. The flavonoid content, expressed as mg of (+)-catechin per g of dry seeds, ranged from 0.24 to 1.43 mg/g. The qualiquantitative composition of polyphenols has been also elucidated by means of high-performance liquid chromatography (HPLC)-diode array detection and HPLC/MS. These investigations showed that rapid tests can contribute to assessing the quality of functional food.  相似文献   

6.
Addition of a nearly tasteless aqueous extract isolated from beans (Phaseolus vulgaris L.) to a model chicken broth enhanced its mouthfulness and complexity and induced a much more long-lasting savory taste sensation on the tongue. Gel permeation chromatography and hydrophilic interaction liquid chromatography/comparative taste dilution analysis (HILIC/cTDA), followed by LC-MS/MS and 1D/2D-NMR experiments, led to the identification of gamma-L-glutamyl-L-leucine, gamma-L-glutamyl-L-valine, and gamma-L-glutamyl-L-cysteinyl-beta-alanine as key molecules inducing this taste-modifying effect. Sensory analysis of aqueous solutions of these peptides showed threshold concentrations between 3.3 and 9.4 mmol/L for an unspecific, slightly astringent sensation. More interestingly, when added to a savory matrix such as sodium chloride and monosodium glutamate solutions or chicken broth, the detection thresholds of these gamma-glutamyl peptides decreased significantly and remarkably enhanced mouthfulness, complexity, and long-lastingness of the savory taste were observed; for example, the threshold of gamma-glutamyl-cysteinyl-beta-alanine decreased by a factor of 32 in a binary mixture of glutamic acid and sodium chloride. As tasteless molecules inducing mouthfulness, thickness, and increasing continuity of savory foods were coined about 10 years ago as "kokumi" flavor compounds, the peptides identified in raw as well as thermally treated beans have to be considered as kokumi compounds.  相似文献   

7.
The effects of a canned mixed green vegetable and fruit beverage, containing broccoli (Brassica oleracea L. var. botrytis L.) and cabbage (Brassica oleracea L. var. capitata L.) as main materials, on serum lipid levels in hypercholesterolemic patients were investigated. Thirty-one adult subjects were administered two cans of the beverage (160 g/can) per day for 3 weeks. Their serum total cholesterol (TC) levels significantly decreased from 6.7 +/- 0.8 to 6.1 +/- 0.6 mmol/L, and, more strikingly, the level of low-density lipoprotein cholesterol (LDL-C) significantly decreased from 4.4 +/- 0.8 to 3.8 +/- 0.7 mmol/L. At 9 weeks after the cessation of the administration, these levels had returned to the preadministration levels. Furthermore, 14 other subjects who were administered one can of the sample for 12 weeks also showed a significant reduction in the levels of serum TC and LDL-C. Thus, daily consumption of this mixed green vegetable and fruit beverage may be useful in lowering serum TC and LDL-C levels in hypercholesterolemic patients.  相似文献   

8.
Seeds of finger millet (Eleucine coracan (L.) Gaertner) and kidney beans (Phaseolus vulgaris L.) were sprouted, autoclaved, and fermented during the processing of a weaning (complementary) food for children. Relative changes in individual amino acids with processing were evaluated. Finger millet and kidney beans both showed a good percentage of essential to total amino acids, with 44. 2-44.9% in finger millet and 44.2-45.1% in kidney beans, when compared to 33.9% for the FAO/WHO reference protein for 2-5 year old children. Sprouting resulted in a significant decrease in lysine in kidney beans. Autoclaving caused significant decreases in histidine, while fermentation significantly decreased phenylalanine and increased tryptophan in finger millet. The leucine-to-lysine ratio, which is an indicator of the pellagragenic character of a protein, was significantly improved in finger millet by both sprouting and fermentation.  相似文献   

9.
Abstract

A study to investigate the effect of lime on dry matter yield of maize (Zea mays) and beans (Phaseolus vulgaris) and nodulation of beans grown in three tropical acid soils (two humic Nitosols and one humic Andosol) was carried out in a greenhouse. The soils ranged from 4.2 to 5.0 in pH; 1.74 to 4.56 in %C; 21.0 to 32.0 meq/100g in CEC; 5.10 to 8.10 meq/100g in exchange acidity; 0.60 to 3.20 meq/100g in exchangeable (exch.) Al and 0.13 to 0.67 meq/ 100g in exch. Mn.

Exchange acidity and exch. Al decreased with increasing levels of lime in the three soils. Exchangeable Al was reduced to virtually zero at pH 5.5 even in the soils which had appreciable initial amounts. Exchangeable Mn also decreased with increasing levels of lime in the two Nitolsos. Exceptional results, however, were obtained with the Andosol where exch. Mn increased ten‐fold with the first level of lime and then decreased with subsequent levels.

In all the soils, mean dry matter yield of beans and maize, and mean nodule dry weight of beans generally increased significantly with increasing lime levels up to pH value of 6.0. The dry matter yield of beans and maize, and nodule weight of beans, however, decreased progressively with increasing lime levels beyond pH 6.0 value. pH range of 5.5 to 6.0 was considered optimum for the growth of maize and beans, and nodulation of beans in these soils.  相似文献   

10.
Antioxidant capacity, as measured by oxygen radical absorbance capacity (ORAC(PE)), total phenolic, total and individual anthocyanins, and proanthocyanidin fraction contents were evaluated in red and white wines from grapes. A comparison in terms of antioxidant capacity is made with nontraditional wines made from highbush blueberry. Blueberries are among fruits that are best recognized for their potential health benefits. In red wines, total oligomeric proanthocyanidin content, including catechins, was substantially higher (177.18 +/- 96.06 mg/L) than that in white wines (8.75 +/- 4.53 mg/L). A relative high correlation in red wines was found between ORAC(PE) values and malvidin compounds (r = 0.75, P < 0.10), and proanthocyanidins (r = 0.87, P < 0.05). In white wines, a significant correlation was found between the trimeric proanthocyanidin fraction and peroxyl radical scavenging values (r = 0.86, P < 0.10). A moderate drink (1 drink per day, about 140 mL) of red wine, or white wine, or wine made from highbush blueberry corresponds to an intake of 2.04 +/- 0.81 mmol of TE, 0.47 +/- 0.15 mmol of TE, and 2.42 +/- 0.88 mmol of TE of ORAC(PE)/day, respectively.  相似文献   

11.
The cytotoxic and antitumor activity of methanolic extract of rice hulls (MERH) were evaluated by the MTT-dye reduction assay against human colon cancer cells and the colonic aberrant crypt foci (ACF) assay in 1,2-dimethylhydrazine (DMH)-injected F344 male rats, respectively. MERH was found to be highly cytotoxic, with IC50 values of 0.5 microg/mL in vitro. Forty weeks of MERH supplementation (50 mg/kg of body weight/day) reduced colonic pre-neoplastic ACF formation by 35% (p < 0.01). An active compound, momilactone B, was isolated from MERH by silica gel chromatography, Sephadex LH-20 chromatography, and HPLC. The cytotoxic activity of momilactone B was evaluated by the MTT-dye reduction, lactate dehydrogenase (LDH), and colony-forming ability assays in human colon cancer HT-29 and SW620 cells. The results indicated that momilactone B from rice hulls might be a new candidate for chemotherapeutic agent against human colon cancer.  相似文献   

12.
As recently shown, a cloudy apple juice (CloA) was effective to modulate colon cancer associated parameters in rats treated with 1,2-dimethylhydrazine (DMH). To identify the bioactive substance classes in CloA, we fractionated CloA to yield a total polyphenol (PF) and a cloud (CF) fraction consisting of proteins, fatty acids, polyphenols, and cell wall polysaccharides. Rats received water (control (Cont)) or CloA, PF, and CF separate or combined (PF-CF) ad libitum for 7 weeks starting one week before the first DMH-injection. As determined by comet assay, the DMH-induced genotoxicity in colonocytes of controls (Cont/DMH: 7.7 +/- 0.5%) was significantly reduced by CloA (3.3 +/- 0.3%) but not by any of the fractions. The crypt cell proliferation induced by DMH (Cont/NaCl: 7.5 +/- 0.6%; Cont/DMH: 14.9 +/- 0.8%) was significantly decreased by CloA (9.4 +/- 0.4%), PF (12.4 +/- 0.7%), CF (11.6 +/- 0.4%), and PF-CF (12.4 +/- 0.6%). Although not statistically significant, CloA tended to reduce the number of large aberrant crypt foci (ACF) (Cont/DMH: 19.0 +/- 3.7; CloA/DMH: 12.3 +/- 1.9), while none of the fractions affected ACFs. Neither CloA nor the fractions changed mRNAs of colonic cyclooxygenases (COX-1, COX-2), glutathione-associated enzymes (GST-M2, gamma-GCS, GST-P), the splenocyte CD4/CD8 ratio, natural killer cell activity, and plasma antioxidant status. These results demonstrate that CloA had a higher cancer-preventive potential than the fractions and further, besides PF, identified CF as an additional bioactive fraction of CloA.  相似文献   

13.
APC-germline mutation creates predisposition for intestinal tumorigenesis. APCMin/+ mice, developing tumors preferentially in the small intestine and only minimally in the colon, were fed pectin-enriched diets (10% galacturonan; degree of methoxylation=37.0 and 70.4%) or standard diet. Pectins used in the present study do not inhibit intestinal tumorigenesis and rather accelerate it in APCMin/+ mice. Both pectins exhibited prebiotic effects associated with high fermentative formation of acetate but producing low butyrate. The differences of the short-chain fatty acid concentrations between cecum and colon and those between colon and feces were larger than expected and increased with cancer progression, indicating an inhibition of butyrate absorption. Pectins transported more bile acids toward the colon than the standard diet and caused a higher generation of secondary bile acids despite lower pH values. Overexpression of COX-2 resulted in lower antioxidative capacity, thus promoting cancer. Apoptosis increased in hyperplasia but decreased in late adenomas. When biological modular design principles are taken into consideration, it can be expected that pectin also reinforces colorectal tumorigenesis of patients suffering from APC gene defects.  相似文献   

14.
The effect of fermentation on antinutritional factors and also on total dietary fiber (TDF), insoluble (IDF) and soluble (SDF) dietary fiber fractions was studied in beans (Phaseolus vulgaris L.). The processes studied were two types of fermentation (lactic acid and natural), and a portion of the obtained flours were processed by autoclaving. The dietary fiber (DF) content and its components were determined using the enzymatic-gravimetric and enzymatic-chemical methods. The TDF content ranged from 24.5% dry matter (DM) in the raw to 25.2% DM in the processed beans. All the processing treatments significantly decreased the SDF content, and irrelevant changes were noticed in the IDF content of processed beans. Cellulose content of all samples was reduced by the processing treatments. Correspondingly, higher amounts of resistant starch was observed in the processed beans, except in the lactic acid fermented ones. However, the levels of pectic polysaccharides and Klason lignin were higher in the samples fermented by Lactobacillus plantarum. The action of microorganisms was determinant for the different degradation of the bean cell wall, disrupting the protein-carbohydrate integration, thus reducing the solubility of DF.  相似文献   

15.
Bush beans (Phaseolus vulgaris L. cv Contender) were grown on perlite with nutrient solution and 0, 1, 2.5 and 5 ppm levels of Na2CrO4 Significant decrease of top growth and chlorosis in trifoliated leaves were observed for 2.5 and 5 ppm Cr, with Cr concentrations (μg/g) in tops:≥ 12.1, in roots:≥ 509.9. Cr decreased K, Na, Mg and Fe concentrations, and increased P and Mn concentrations in roots. In tops decreased N, K, Na and Fe concentrations and increased Mn and Ca concentrations were observed, Translocation of P, Zn, Cu and Fe was inhibited; Ca and Mn translocation was generally enhanced. P/Fe ratio was increased up to 60% in chlorotic plants, indicating a shift from Fe2+ to Fe3+.  相似文献   

16.
Previous studies reported that peracetylated (-)-epigallocatechin-3-gallate (AcEGCG) has antiproliferative and anti-inflammatory activities. Here, we evaluated the chemopreventive effects and underlying molecular mechanisms of dietary administration of AcEGCG and EGCG in dextran sulfate sodium (DSS)-induced colitis in mice. The mice were fed a diet supplemented with either AcEGCG or EGCG prior to DSS induction. Our results indicated that AcEGCG administration was more effective than EGCG in preventing the shortening of colon length and the formation of aberrant crypt foci (ACF) and lymphoid nodules (LN) in mouse colon stimulated by DSS. Our study observes that AcEGCG treatment inhibited histone 3 lysine 9 (H3K9) acetylation but did not affect histone acetyltransferase (HAT) activity and acetyl- CREB-binding protein (CBP)/p300 levels. In addition, pretreatment with AcEGCG decreased the proinflammatory mediator levels by down-regulating of PI3K/Akt/NFκB phosphorylation and p65 acetylation. We also found that treatment with AcEGCG increased heme oxygenase-1(HO-1) expression via activation of extracellular signal-regulated protein kinase (ERK)1/2 signaling and acetylation of NF-E2-related factor 2 (Nrf2), thereby abating DSS-induced colitis. Moreover, dietary feeding with AcEGCG markedly reduced colitis-driven colon cancer in mice. Taken together, these results demonstrated for the first time the in vivo chemopreventive efficacy and molecular mechanisms of dietary AcEGCG against inflammatory bowel disease (IBD) and potentially colon cancer associated with colitis. These findings provide insight into the biological actions of AcEGCG and might establish a molecular basis for the development of new cancer chemopreventive agents.  相似文献   

17.
Symptoms of manganese toxicity in beans (Phaseolus vulgaris L) In water culture experiments with bush bean plants (Phaseolus vulgaris L. var. ?Red Kidney”?) the macro- and micro-symptoms of manganese toxicity had been studied. Typical symptoms of Mn toxicity are small distinct blackish-brown spots, first at the older leaves and at more severe toxicity also at the petals and stems. Using the autoradiographic technique on 54Mn-distribution and comparing this with corresponding light microscopic studies it could be demonstrated that the blackish-brown spots in the leaves resemble Mn-precipitations. These precipitations are Mn-compounds of higher oxidated form and are primarily localized in the walls of cells in vicinity of the vessels. The extend to which these precipitations occur is not only a function of the Mn-content of the leaves but also of their age. At comparable Mn-content the extend of the precipitation increases with the leaf age. As secondary symptom of Mn-toxicity under certain conditions (presence of silicon e.g.) induced Fe deficiency (chlorosis of the youngest leaves) and Ca deficiency (?crinkle leaf”?) may occur. It is assumed that the process of Mn precipitation within the leaves is enzymatically regulated. The severe reduction in the growth of leaf blades at Mn toxicity is presumably related to an interference with the growth hormon balance.  相似文献   

18.
The objective of this work was to evaluate extrusion cooking as a means to improve the nutritional properties of Phaseolus vulgaris L. that had been stored either at 42 degrees C and 80% relative humidity for 6 weeks or for periods >1 year in cereal stores in tropical conditions. Storage under these conditions resulted in an increase in cooking time increased (7.7- and 12-fold, respectively) as a result of development of the hard-to-cook (HTC) defect. Single-screw extrusion of the milled beans was carried out at four barrel temperatures and two moisture contents. The extrudate bulk density and water solubility index decreased with increasing temperature, whereas the water absorption index increased due to the higher proportion of gelatinized starch in the extruded samples. Both fresh and HTC beans contained nutritionally significant amounts of lectins, trypsin, and alpha-amylase inhibitors, which were mostly inactivated by extrusion. Extrusion also caused a considerable redistribution of insoluble dietary fiber to soluble, although the total dietary fiber content was not affected. Changes in solubility involved pectic polysaccharides, arabinose and uronic acids being the main sugars involved. Stored beans subjected to extrusion cooking showed physical and chemical characteristics similar to those of extrudates from fresh beans.  相似文献   

19.
Samples of common and biofortified beans ( Phaseolus vulgaris ), both raw and cooked (autoclaved at 120 degrees C for 20 min) were analyzed for their polyphenol composition. Polyphenols were identified via HPLC-UV/diode array detection. Cooking favored the extraction of polyphenols without the need of a hydrolysis step, a fact that is of interest because this is the usual form in which beans are consumed. The main differences between white and colored beans were the presence of free kaempferol (13.5-29.9 microg g(-1)) and derivatives (kaempferol-3-O-glucoside) (12.5-167.5 microg g(-1)), only in red and black beans. An in vitro digestion (pepsin, pH2; pancreatin-bile extract, pH 7) was applied to beans to estimate bioaccessibility of individual polyphenols. Kaempferol from seed coats exhibited high bioaccessibility (45.4-62.1%) and a potent inhibitor effect on Fe uptake at concentrations ranging from 0.37 to 1.30 microM. Caco-2 cell ferritin formation was used to evaluate Fe uptake. Cell Fe uptake was significant only from white beans.  相似文献   

20.
A previous study showed β-glucan with low molecular weight (MW, 1.56×10(5) g/mol) bound more bile acid and produced greater amounts of short-chain fatty acids (SCFA) than did β-glucan with high MW (Mn=6.87×10(5) g/mol). In the current study, β-glucan extracted from oat flour was fractionated into six different MW levels (high MW, 7.09×10(5); low level 1 (L1), 3.48×10(5); L2, 2.42×10(5); L3, 1.61×10(5); L4, 0.87×10(5); and L5, 0.46×10(5) g/mol) and evaluated to find the optimum MW affecting in vitro bile acid binding and fermentation. The β-glucan fractions with 2.42×10(5)-1.61×10(5) g/mol (L2 and L3) bound the greatest amounts of bile acid. After 24 h of fermentation, no differences were found in total SCFA formation among L1, L2, L3, and L4 fractions; however, the high MW and L5 MW fractions produced lower amounts of total SCFA. Thus, the optimum MW of β-glucan to affect both hypocholesterolemic and antitumorigenic in vitro effects was in the range of 2.42×10(5)-1.61×10(5) g/mol. This MW range also was the most water-soluble among the MWs evaluated.  相似文献   

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