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971.
Immunoreactivity and amino acid content of fermented soybean products   总被引:1,自引:0,他引:1  
Food allergy has become a public health problem that continues to challenge both the public and the food industry. The objective of this research was the detection and quantification of the major human allergenic soy proteins and to study the reduction in immunoreactivity and improvement of amino acid content after fermentation of soybean flour. Fermentation was carried out in the solid state of cracked seeds inoculated with Aspergillus oryzae, Rhizopus oryzae, and Bacillus subtilis and in the liquid state of milled soybean flours fermented naturally by microorganisms present only in the seeds or by inoculation with Lactobacillus plantarum. ELISA and Western blot were used to quantify IgE antibody response, and HPLC was used to identify and quantify total amino acids. L. plantarum fermented soy flour showed the highest reduction in IgE immunoreactivity (96-99%) depending upon the sensitivity of the plasma used. Among the solid fermented products, the lowest reduction in immunoreactivity was obtained when mold strains, R. oryzae and A. oryzae, were used (66 and 68%, respectively, for human plasma 97.5 kUA/L). Among the solid fermented products, those inoculated with B. subtilis yielded a 81 and 86% reduction in immunoreactivity against both human plasma 97.5 IgE kUA/L and human pooled plasma samples, respectively. When soybean was subjected to liquid fermentation, most of the total amino acids increased significantly ( p < or = 0.05). In solid fermentation with R. oryzae, only Ala and Thr content improved. Fermentation can decrease soy immunoreactivity, and there is potential of developing nutritious hypoallergenic soy products.  相似文献   
972.
Genetic and demographic studies of fragmented populations of common plant species often reveal negative impacts that are likely to constrain persistence. Examining species that are broadly representative of functional groups within fragmented landscapes is one approach to providing a better understanding of how these processes will influence vegetation persistence. Acacias are a significant component of the Australian flora, with Acacia dealbata being a common and representative species of fragmented landscapes across New South Wales. Previous reproductive assessments of fragmented A. dealbata populations indicated significant constraints for small populations through low reproductive output mediated by fertilisation success. This study examined genetic diversity, mating system, and progeny growth parameters of the seed crops produced by these populations to assess whether further constraints to persistence could be detected. Spatially explicit simulation studies were also conducted to assess the persistence likelihood of fragmented populations. Landscape parameters such as population size and plant density were useful predictors for some of the genetic and demographic responses, but a poor response signal was generally observed. Strong evidence for a self-incompatibility mechanism was observed in A. dealbata and is likely to be the major driver of population persistence. Self-incompatibility in small populations limits mate availability and eliminates inbred progeny early in the reproductive cycle leading to poor reproductive output. The simulation data provides further evidence that mate limitation in smaller populations (<200 plants and 40 S alleles) constrains reproductive output and persistence. These data indicate that introducing new germplasm to smaller populations can dramatically improve their persistence likelihood.  相似文献   
973.
Myrosinase is a cytosolic plant enzyme present in daikon ( Raphanus sativus, Japanese white radish) roots that hydrolyzes 4-methylthio-3-butenyl glucosinolate (MTBGLS) into the natural pungent agent 4-methylthio-3-butenyl isothiocyanate (MTBITC), which possesses antimicrobial, antimutagenic, and anticarcinogenic properties. The concentration of MTBGLS, myrosinase activity, and production of MTBITC in seven daikon varieties (one conventional and six heirlooms) were determined to rank the activity of the glucosinolate-myrosinase system and identify critical factors influencing the production of MTBITC. The six heirloom varieties produced 2.0-11.5 times higher levels of MTBITC as compared to the conventional variety, Aokubi, which is consumed by the present Japanese population. The myrosinase was located exclusively in the outer epidermal layer in Aokubi, and MTBGLS was widely distributed throughout the root tissue. Although the skin is a potentially rich source of myrosinase in Aokubi, the skin is usually peeled off in the current practice of preparing daikon for cooking. New practices are therefore proposed for the preparation of daikon tubers that eliminate the peeling of the skin to avoid removing the enzyme needed to convert MTBGLS to the health-beneficial MTBITC. It is also concluded that the consumption of heirloom daikon varieties in addition to changes in food preparation will optimize the health benefits of daikon.  相似文献   
974.
Photostimulated luminescence (PSL) and thermo-luminescence (TL) analyses were conducted to detect irradiated kiwifruits. Samples were irradiated with Co-60 gamma-rays at 0-2 kGy. The freeze-dried kiwifruit peel showed 309 photon counts (PCs) for nonirradiated samples that accounted for less than the lower threshold value (700 counts/60 s, negative) and above 9306 PCs for 1 and 2 kGy-irradiated samples, which was higher than the upper threshold value (5000 counts/60 s, positive). However, PSL signals of irradiated samples remarkably decreased after 6 weeks of storage. The TL measurement using minerals isolated from the whole kiwifruit surface revealed a glow curve (TL 1) with a low intensity at 200-300 degrees C in nonirradiated samples but with a higher intensity at around 180 degrees C in irradiated samples at 1 kGy or more. The TL ratios, integrated areas of TL 1/TL 2 that was measured after 1 kGy re-irradiation for the TL 1-tested minerals, were less than 0.1 in nonirradiated samples and higher than 0.1 in irradiated ones and could verify TL 1 results. The inorganic dust minerals used were mainly composed of feldspar and quartz.  相似文献   
975.
Hydrocarbons and 2-alkylcyclobutanones in sesame seeds ( Sesamum indicum L.) irradiated at 0.5-4 kGy were used to determine the effect of subsequent steaming, roasting, and oil extraction from the roasted samples on the changes in their concentrations. The concentrations of radiation-induced hydrocarbons increased almost linearly (R(2) = 0.8671-0.9953) with the applied dose. The hydrocarbons, 1,7-hexadecadiene and 8-heptadecene, were detected only in the irradiated samples before and after three types of treatments at doses > or =0.5 kGy, but they were not detected in non-irradiated samples before and after treatment. These two hydrocarbons could be used as markers to identify irradiated sesame seeds. The concentrations of the three detected 2-alkylcyclobutanones, 2-dodecylcyclobutanone (2-DCB), 2-tetradecylcyclobutanone (2-TCB), and 2-(5'-tetradecenyl)cyclobutanone (2-TeCB), linearly increased with the irradiation dose. These compounds could be detected at doses > or =0.5 kGy but not in non-irradiated samples. The three types of treatments had no significant effect on the levels of 2-alkylcyclobutanones.  相似文献   
976.
(-)-Epigallocatechin gallate (EGCG), a polyphenolic compound found in green tea, is a promising chemopreventive agent against cancer due to its strong antiproliferative effects on cancer cells; however, its possible toxicity and carcinogenicity must be investigated before EGCG can be used as a dietary supplement for chemoprevention. The inhibition of gap junctional intercellular communication (GJIC) is strongly associated with carcinogenesis, particularly the tumor promotion process; thus, we investigated the effects of EGCG on GJIC in WB-F344 normal rat liver epithelial (RLE) cells. EGCG, but not (-)-epicatechin (EC), another polyphenol found in green tea, inhibited GJIC in a dose-dependent and reversible manner in RLE cells. EGCG also induced the phosphorylation of connexin 43 (Cx43), a major regulator of GJIC. The phosphorylation of extracellular signal-regulated protein kinase 1/2 (ERK1/2) was also observed in EGCG-treated RLE cells. The inhibition of GJIC and phosphorylation of Cx43 and ERK1/2 by EGCG were completely blocked by U0126, a pharmacological inhibitor of mitogen-activated protein kinase/ERK kinase. EGCG generated a larger amount of hydrogen peroxide than EC in a dose-dependent manner. Furthermore, catalase partially inhibited the EGCG-induced inhibition of GJIC and the phosphorylation of Cx43 and ERK1/2. These results indicated that EGCG inhibited GJIC mainly due to its prooxidant activity.  相似文献   
977.
Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT), which is a key enzyme in triglyceride synthesis in eukaryotic organisms, has been proposed as one of the drug targets for treating obesity, type II diabetes mellitus, and metabolic syndrome. Bioassay-guided fractionation of EtOH extract of the flower buds of Tussilago farfara , using an in vitro DGAT enzyme assay, resulted in the isolation of four known sesquiterpenoids, tussilagonone (1), tussilagone (2), 7beta-(3-ethyl-cis-crotonoyloxy)-1alpha-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (3), and 8-angeloylxy-3,4-epoxy-bisabola-7(14),10-dien-2-one (4). DGAT1 inhibitory activity was studied by in vitro DGAT assay using rat liver microsomes and HepG2 cell microsomes. They showed DGAT1 inhibition with IC(50) values of 99.2 (1), 18.8 (2), 47.0 (3), and 211.1 (4) microM (for rat liver microsomes) and >1 mM (1), 49.1 (2), 160.7 (3), and 294.4 (4) microM (for HepG2 cell microsomes), respectively. Compound 2 showed the most potent inhibition against microsomal DGAT1 derived from rat liver and human hepatocellular carcinoma HepG2 cells and also significantly inhibited triglyceride synthesis by suppressing incorporation of [(14)C]acetate or [(14)C]glycerol into triglycerides in HepG2 cells. These findings suggest that tussilagone is a potential lead compound in the treatment of obesity and type 2 diabetes.  相似文献   
978.
979.
The interaction between polychlorobiphenyls (PCBs) and an alkaline amino acid reagent (NaL) in solutions and a gray forest soil contaminated by these solutions was studied by IR spectroscopy and gas-liquid chromatography depending on the component concentrations and reaction time. Intermolecular interaction of PCBs with NaL by hydrogen bonds of hydroxyl, amide, and carboxyl groups, as well as the detachment of chlorine from the aromatic ring of PCB molecules, was revealed in solutions. A significant decrease (by 32 to 75%) in total PCBs was observed in solutions and gray forest soil in the presence of the amino acid reagent depending on the concentration of the reagent and the amount of its addition to soil samples. Changes in the relative content of low-and high-chlorinated PCB congeners were revealed in solutions and PCB-contaminated gray forest soil in the presence of the amino acid reagent, which indicated their stepwise dechlorination.  相似文献   
980.
Purpose

Accounting for ionic strength and ion association, the degree of calculated supersaturation with CaCO3 of gleyic solonetz and molic solonetz soil solution is high. The purpose of the research was to reveal the effect of the water-dissolved organic matter (DOM) on the calcium carbonate equilibrium (CCE) in soil solution, to create a thermodynamic model of carbonate association and complexation with DOM and heavy metals (HMs), and to correct the principal of soil management.

Materials and methods

Object of research—Kastanozem complex of the dry steppe, Rostov Oblast, Russia. The water extraction of soluble salts was made at the water-to soil-ratio 5:1 and analyzed using standard methods. DOM content was determined by Strosser (J Agrobiol 27:49–60, 2010). The soil solution macro-ion equilibrium composition was calculated using ION-2 program (Endovitsky et al. 2009). DOM role in soil solution supersaturation with СаСО3 was assessed, comparing C content in real solution and in identical artificial solution prepared without organic matter. Taking into account the ion association, the molar fractions of free and bound HM ion were calculated using microelement association coefficient, kas(ME). The soil liquid-phase saturation with CaCO3 was characterized by the ratio of the real solubility product (S) to the thermodynamic solubility product (S0): К?=?S/S0.

Results and discussion

The soil solution supersaturation with CaCO3 was characterized by the product of analytical concentrations (S), equilibrium concentrations [accounting ion activity (SI), ion association (SII), ion association and complexation (SIII)], and the thermodynamic solubility product (S0). To evaluate the role of DOM in soil solution supersaturation with CaCO3, the initial pure Ca (HCO3)2 solution series was prepared. The humic and fulvic acids from the illuvial horizon of gleyic solonetz with concentrations of 20 mg C L?1 and 120 mg C L?1 decreased the CaCO3 precipitation compared with initial soil solution. The release of CaCO3 from soil water extracts containing water-soluble organic matter was 1.2–1.9 times less compared with identical artificial solution not containing organic matter. The HM binding by carbonates is proportional to the DOM content.

Conclusions

In molic solonetz and gleyic solonetz, the neutralization of the soda should be assessed by the soil solution supersaturation with CaCO3. To calculate the degree of HM passivation in soil solution containing DOM, the coefficient of soil solution oversaturation with CaCO3 is proposed. For reducing soil organic matter and DOM mobility and loss from soil, as well as for Pb passivation, intra-soil mechanical processing, intra-soil waste management, and intra-soil watering are proposed.

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