Change in mutagenicity in white rice after accelerated and long-term storage

ABSTRACT:  Certain reactions that occur in food during storage, such as nonenzymatic browning and lipid oxidation, form compounds that have been shown to be mutagenic. It is possible that over long storage periods, significant amounts of these products could be formed. Although some research has been published concerning the mutagenicity of foods due to processing or cooking, little research has been done regarding mutagenicity of foods stored for an extended time. The objective of this research was to determine the potential mutagenicity of white rice held in accelerated and long-term storage using the Ames Salmonella /microsome assay. Fresh long-grain white rice was packaged in foil laminate pouches and held at 60 °C for 18 wk. Rice stored for > 25 y in an oxygen-free environment at or below room temperature in size number 10 cans was obtained from residential storage. The standard plate-incorporation method was used to evaluate the mutagenic potential of all treatments using Salmonella typhimurium tester strains TA97a, TA98, TA100, and TA102. Samples were plated at 5 dilutions with and without rat liver S9 enzyme. A solvent control was also plated for each strain. Treatments yielding counts at least double the solvent control level were considered mutagenic. Plate counts for all treatments fell well below the required doubling of the solvent control value. White rice held in accelerated and long-term storage appears not to increase in mutagenic compounds as measured by the Ames assay, supporting its use for long-term storage purposes such as emergency preparedness and humanitarian food aid.     

Clinical manifestations of cross-allergic reactions to food among children

Scientists have recently studied the frequency and possible forms of clinical manifestations of cross-reactivity to food among 239 of Abakan at the age from 6 month to 15 years with skin, respiratory and combined manifestation of atopy It was proved that risk factors of development of cross-reactivity to food occur among 80% of children who have various forms of allergic diseases moreover the cross allergic reactions between the foodstuffs most frequently occur with the gastrointestinal and with skin forms of food allergy and the cross allergic reactions between the pollen and food allergens more frequently occut with the respiratory forms of atopy and dermorespiratory syndrome. Considerably more rarely this type of reactions is discovered between the epidermal and food allergens, which most frequently were revealed with the dermatorespiratory syndrome.     

The effect of various levels of chitosan in rat diet on vitamins assimilation under their combined deficiency

he effect of chitosan inclusion in the semi-synthetic diet of rats at a dose of 0,24 and 0,9% of dry weight on vitamin assimilation under combined moderate and deep deficiency has been studied. Four-week introduction of chitosan did not have a significant effect on levels of vitamins C, B1, B2 and A in the liver of animals, on vitamin B2 blood plasma concentration and thiamine and riboflavin urinary excretion regardless of the degree of vitamin deficiency intensity. The significantly decrease of vitamin E blood plasma concentration has been observed at high dose of chitosan in the diet under moderate vitamin deficiency, whereas under deep deficit such reduction has been detected even at a low dose. Thus, long-term chitosan inclusion in the diet under existing polyhypovitaminosis can lead to the deterioration of the sufficiency with fat-soluble vitamins.     

To substantiation of vitamin and mineral level in fortified food products

This review outlines the scientific rationale and commentary for the introduction of sanitary rules and norms governing the enrichment of foods of mass consumption with vitamins and minerals, which were harmonized with EU documents and Codex Alimentarius.     

Effect of vitamin beverages on vitamin sufficiency of the workers of Pskov Hydroelectric Power-Plant

The research of influence of vitamin complexes in the form of a drink or kissel on vitamin sufficiency of working persons has been carried out. Long inclusion (6,5 months) in a diet of vitamin drinks containing about 80% from recommended daily consumption of vitamins, was accompanied by trustworthy improvement of vitamins C and B6 sufficiency and prevention of seasonal deterioration of beta-carotene status. As initially surveyed have been well provided with vitamins A and E, their blood serum level increase had not occurred.     

Assessment of nutritional status of patients in the later period after renal transplantation

This article summarizes the modern approach for estimation of nutritional status (medical history, anthropometric, clinical and biochemical measures) in patients in the late period after kidney transplantation. It is showed that main complications in the late posttransplant period (cardiovascular diseases, diabetes, obesity, malnutrition) determine the need of complex assessment of nutritional status in these patients with the object of improve outcomes after transplantation.     

Effect of coenzyme Q10 and taurine on the availability of vitamins in the rat experiment

It has been observed that coenzyme Q10 (100 mg per 1 kg body mass) and taurine (1% in drinking water) treatment of rats has differently directed effect on vitamin A and E level in liver and blood serum. Coenzyme Q10 consumption has been accompanied with a tendency to increasing or an increase of vitamin content, while taurine consumption lead to the reverse effect. Both coenzyme Q10 and taurine addition caused diene conjugates decrease in blood serum. Supplementary coenzyme Q10 or taurine intake did not influence on rat liver vitamin B1 and B2 content.     

Effects of cyclodextrins on the flavor of goat milk and its yogurt

Goat milk fat includes several branched chain fatty acids (BCFAs), like 4-methyloctanoic acid, which when free, are responsible for goaty flavor. This flavor limits the market opportunities for goat milk. Prior research showed that cyclodextrins (CDs) can reduce goaty flavor, presumably by binding free fatty acids. This research extends that observation. In odor ranking trials in citrate buffer at pH 4.8, β-CD concentrations between 0% and 0.35% were increasingly effective in reducing odor intensity due to 4-methyloctanoic acid, but only when present in high molar excess. α-CD was also effective, but γ-CD was not. In lipase-treated goat milk only β-CD was effective but at much lower molar excess, a difference potentially explained by several factors. One was that BCFAs bind to CDs in marked preference to their straight chain isomers. Displacement experiments with phenolphthalein disproved that hypothesis. The ability of β-CD to reduce goaty flavor intensity extended to yogurt. An analytical panel showed that flavor of goat yogurt was reduced by addition of β-CD, but only if added before heating and fermentation. A hedonic trial showed that consumers preferred unsweetened and sweet/vanilla-flavored goat yogurt more when β-CD was included, P = 0.004 and 0.016, respectively. Males liked all yogurts more than females (P < 0.01), but there was a treatment × gender interaction (P = 0.016) for sweet/vanilla yogurt: sweet/vanilla masked the goaty flavor for males but not females. This results parallels previously demonstrated gender effects for sheepmeat flavor caused by BCFAs. PRACTICAL APPLICATION: β-Cyclodextrin masks goaty flavor in yogurt, and with its GRAS status means it could be used in commercial goat yogurts and similar products so the real or perceived nutritional advantages of goat milk are not lost to goaty flavor.     

Medical and prophylactic properties lipids and antioxidants derived from sea hydrobionts

Recent researches in the field of studying medical-preventive activity of lipids and natural antioxidants derived from sea hydrobionts at carbohydrate and lipid metabolic imbalances were analyzed. On experimental models of hyperlipidemia and a diabetes the optimum dozes and polyunsaturated fat acids omega-3/omega-6 in structure of phospho- and glycolipids derived from sea macrophytes Sargassum pallidum, Ulva fenestrata, Zostera marina, and also antioxidants-- polyhydroxynaphthoquinone a echinochrome. A derived from flat sea urchin Scaphechinus mirabilis and mixes of polyphenols from sea grass Zostera marina were determined. Prospective mechanisms of polar lipids, containing various polyunsaturated fat acids and specified above antioxidants are presented on the basis of the received results and the analysis of published data.     

时效制度对GH2132合金航空发动机螺栓性能的影响

研究不同时效制度对国产高温合金GH2132航空发动机螺栓性能的影响。结果表明,与标准时效制度720 ℃×16 h相比,680℃×24h时效能明显提升GH2132航空发动机螺栓类产品的硬度、室温抗拉强度、高温抗拉强度,特别是高温持久性能的保持时间可提高27%以上。虽然其疲劳寿命有所降低,但仍远高于航空发动机螺栓技术条件规定的平均6.5万次以上。