腐乳抗氧化作用研究进展

从腐乳抗氧化作用的角度入手,阐述了抗氧化的评价方式,讨论了前酵菌种、后酵汤料成分对腐乳的抗氧化性的影响,综述了腐乳中大豆异黄酮、大豆多肽、超氧化物歧化酶、大豆皂甙等潜在的产生抗氧化作用因子的研究进展,并展望了腐乳中抗氧化功能因子的研究前景.     

The effect of sodium chloride on gluten network formation and rheology

Gluten samples were obtained from two wheat flours with different levels of total protein in the presence or absence of sodium chloride (2% flour base). The dynamic oscillation rheology, large extensional deformation, confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM) and chemical analysis of disulfide bond linkages and the ratio of polymeric glutenins and monomeric gliadins were used to investigate the effect of salt on the structure and rheological properties of gluten. CLSM and TEM images showed that NaCl caused the gluten to form fibrous structure. The presence of NaCl increased non-covalent interactions and β-sheet structure, measured by FTIR, in gluten proteins. The gluten matrix formed with salt resulted in higher tan δ values corresponding to a less elastic network when measured using oscillatory rheometry. Large deformation extensional measurements showed that the maximum force to fracture were lower for the gluten samples prepared in the presence of NaCl. The results from this study indicate that changes in the solvent quality due to the presence of NaCl during dough mixing result in different molecular conformation and network structure of gluten proteins which contributed to the differences in the rheological properties.     

Iron status and growth of rats fed different dietary iron sources

The present study was carried out to investigate the availability of iron from spirulina, whole wheat, whole egg and standard ferrous sulphate in terms of haemoglobin formation, serum and tissue iron levels. Male albino Wistar rats were first depleted of iron by giving low-iron diet (9 ppm) and bleeding 1–2 ml blood at weekly intervals for a period of 21 days. The anaemic rats were repleted with iron sources at a level of 35 ppm for 21 days. Rats receiving whole egg gained significantly (p<0.01) higher weight than the rest of the three groups. The increase in haemoglobin was significantly higher with ferrous sulphate than with whole wheat (p<0.05), spirulina and whole egg (p<0.01). Feeding of ferrous sulphate, whole egg and spirulina produced significantly higher tissue iron levels than feeding of whole wheat. Thus, availability of iron from spirulina and whole egg were found to be comparable to that of the standard.     

Effect of amino acid supplementation on protein quality of soy-based infant formulas fed to rats

The powder forms of soy-based infant formulas obtained from four manufacturers were fed to weanling rats for two weeks, as the sole source of protein in diets containing 8% protein, 20% fat, and adequate amounts of minerals and vitamins. The relative protein efficiency ratio (RPER) and the relative net protein ratio (RNPR) values (casein + methionine=100) of diets containing unsupplemented formulas were 71–81 and 78–85, respectively. Supplementation of the formula diets with lysine (0.2%), methionine (0.2%), threonine (0.1%) or tryptophan (0.05%) increased the level of the supplemental amino acid in rat serum but generally failed to improve the RPER or RNPR values. Addition of all four essential amino acids to the formula diets, however, caused a marked improvement in their protein quality (RPER or RNPR values=100). The data suggested that proteins in soy-based formulas could be marginally co-limiting in several indispensable amino acids.Presented in part at the 202nd annual meeting of the American Chemical Society, New York City, 25–30 August 1991.     

The effects of sodium chloride application to pasture, or its direct supplementation, on dairy cow production and grazing preference

The experiment aimed to examine the effects of sodium chloride (NaCl) application to pasture on dairy cow production, distinguishing the effects of Na supply on pasture production from the direct effects on animal production, and also to examine the preference of dairy cows for sodium-fertilized pasture. Twenty-four dairy cows were grazed in six treatment areas with three fertilizer levels—all (A), one-half (H) or none (N) of the area fertilized with 50 kg NaCl ha⁻¹, and with or without 50 g cow⁻¹ day⁻¹ NaCl supplementation (+, −) offered in concentrate feed. The experiment was a changeover design with four 3-week periods. NaCl fertilization increased herbage growth rate and Na, Cl and calcium (Ca) contents and reduced K content. Milk yield and liveweight gain were increased by NaCl application to pasture but not by direct supplementation. Milk fat content was increased with increasing Na concentration in the diet. Grazing time was increased by NaCl application to pasture, but only cows not receiving direct NaCl supplementation preferred NaCl-fertilized pasture. Ruminating time was increased both by NaCl application to pasture and by direct supplementation. It is concluded that in the warm, dry conditions of this experiment, increasing Na supply to natrophilic herbage increased both pasture and animal production, and that within the range 3–8 g Na kg⁻¹ dietary DM, increasing Na supply to the cow increased milk fat content.     

The effect of chloride fertilization on blackspot susceptibility and other quality characteristics and on yield of potato

Summary Trials were carried out in two years on a sandy loam and on a heavy clay soil with two cultivars to examine the potential of chloride fertilization as a tool to reduce blackspot susceptibility of potatoes and to investigate other effects on yield and quality. Blackspot susceptibility was significantly reduced in cv. Marijke, but not in cv. Bintje as a result of increasing doses of applied chloride from 0 to 400 kg ha1. Dry matter concentration, assessed as under-water weight, was reduced by chloride in both cultivars at the two locations. Fry colour of French fries was improved by chloride. Applying 400 kg ha⁻¹ Cl⁻ to both soil types decreased net tuber yield >35 mm of cv. Bintje but not of cv. Marijke. Chloride caused slower emergence, retarded crop development and less stems per plant on the sandy loam soil but not on the heavy clay soil.     

The effect of forage type and level of concentrate supplementation on the performance of spring-calving dairy cows in early lactation

Abstract In 1993 and 1994, 40 cows in early lactation in early spring were assigned randomly to four feeding treatments. One group of cows was kept indoors with access to grass silage ad libitum, plus 6 kg of concentrate daily. The other three groups had access to grass pasture (5–6 h per day in 1993 and 11–12 h per day in 1994) plus grass silage similar to that fed to the previous group while indoors plus 6, 4 or 2 kg of concentrate daily. The average daily allocations of herbage (> 3·5 cm) were 8·5 and 14·0 kg DM cow^?1 day^?1 in 1993 and 1994 respectively. The treatments were applied for 8 weeks (26 February to 23 April) in 1993, and 7 weeks (11 March to 29 April) in 1994. Cows with access to pasture had lower (P < 0·001) silage dry‐matter (DM) intakes and higher (P < 0·001) total forage DM intakes in both years than those kept indoors. This resulted in significantly higher yields of milk, fat, protein and lactose. Similarly, milk protein concentration was higher (P < 0·05 in 1993; P < 0·001 in 1994). There was a significant linear increase in total DM intake in both years with increased concentrate supplementation. In 1993, there was a linear increase in milk (P < 0·01), fat (P < 0·01), protein (P < 0·001) and lactose (P < 0·01) yields with increased concentrate supplementation. In 1994, only milk protein yield (P < 0·05) was increased. Concentrate supplementation had no effect on milk composition or liveweight change. Cows with access to grazed grass had higher liveweight gains (P < 0·05) than those kept indoors in both years. In 1993, increasing the energy intake increased the processing qualities of the milk produced. The results showed that access to grass pasture resulted in higher milk production, in reduced silage requirement and in reduced level of concentrate supplementation required for a given level of milk production with spring‐calving cows in early lactation compared with those kept indoors.     

A study on composition and hypolipidemic effect of dietary fibre from some plant foods

Dietary fibre content of foods namely,khejri beans (Prsopsis cinceria),peepalbanti (Ficus religiosa),barbanti (Ficus bengalensis),gullar (Ficus glomerata) andteent (Capparis decidua) varied from 38.5% to 55.7%. Cellulose and lignin were predominating constituents inpeepalbanti,barbanti andgullar; hemicellulose inteent and pectin inkhejri beans. Fibre from all these plant foods, fed at the 10% dietary level to rats, induced a greater resistance to hyperlipidemia than cellulose.Teent had the most pronounced hypocholesterolemic effect which appeared to operate through increased fecal excretion of cholesterol as well as bile acids. Dietary hemicellulose showed a significant negative correlation with serum and liver cholesterol and a significant positive correlation with fecal bile acids. The dietary fibre influenced total lipids, cholesterol, triglycerides and phospholipids of the liver to varying extents.     

The effect of a silage additive and level of concentrate supplementation on silage intake, animal performance and carcass characteristics of finishing beef cattle

An experiment was carried out to examine silage fermentation, effluent production and aerobic stability in unwilted grass silage, which was either ensiled without additive or with a commercially available blend of ammonium hexamethanoate, ammonium hexapropionate and octanoic acid (6 l t^?1, Maxgrass, BP Chemicals Ltd., Northwich, UK) and to determine alternative approaches to obtaining the same performance in finishing beef cattle. Seventy‐two Limousin × Friesian and Charolais × Friesian steers (mean initial live weight 424 kg s.d. 28·3) were blocked into groups of nine according to live weight and previous performance and offered silage, either with or without the additive, and supplemented with 0, 1·5, 3·0 or 4·5 kg d^?1 of a concentrate with a crude protein content of 150 g kg^?1 DM or allocated to a pre‐experimental slaughter group to enable calculation of daily carcass gain. Daily silage intakes were recorded for 112 days. At the end of the experiment, all cattle were slaughtered and daily carcass gain, omental, mesenteric, perinephric and retroperitoneal fat depots [kidney‐knob and channel fat (KKCF)], fatness, conformation, subcutaneous fat depth over M. longissimus dorsi muscle and carcass fat, protein and bone contents were assessed. Across all levels of supplementation, cattle offered the silage with the additive showed significantly (P < 0·001) higher daily DM intakes than those offered the silage without additive. Cattle offered the silage with the additive but unsupplemented had significantly (P < 0·001) higher daily carcass gains than those offered the silage without additive and unsupplemented. The response in carcass gain was 76 and 35 g kg^?1 additional concentrate for the silages with and without the additive respectively.     

The effect of fat supplementation in Shami goat diets on milk production and composition, does body weight and growth performance of their suckling kids

The aim of this study was to evaluate the effect of feeding a dry fat source to Shami does on their milk production and composition, body weight change, weaning weight and average daily gain of their suckling kids. For this purpose we used thirty two multiparous Shami does weighing (47.43 +/- 1.38 kg) and randomly assigned into four dietary treatments in a Completely Randomized Design (CRD) set. Does were housed with their suckling kids and fed one of four isonitrogenous total mixed rations containing 0, 2, 3 or 4% of dry fat. Milk production and milk fat content were higher (p < 0.05) for fat treated does, with no differences between 2% fat level and control group while there was no differences among groups in milk protein content. Final body weight of does was not affected by fat supplementation while body weight changes were higher (p < or = 0.05) for fat treated groups. Weaning weight and average daily gain of suckling kids were increased (p < or = 0.05) for fat treated does, with no differences between 2% fat level and control group. It is concluded that supplemental fat to does rations at 3 or 4% during their postpartum period can improve their milk production and milk fat content, as well as body weight change of does, weaning weight and average daily gain of suckling kids, without any effect on their milk protein content.     

The effects of cereal supplementation of grass and maize silages

Grass and maize silages were fed alone and with two levels of a barley supplement to Friesian steers of about 300 kg liveweight. The organic matter (OM) intakes of grass and maize silage were similar although the OM digestibilities of the silages were 0·722 and 0·649 respectively. For both silages, barley supplementation increased total OM intake and total digestible OM intake by 0·46·0·08 and 0·37·0·06 g per g OM of supplement respectively. Liveweight gains on grass and maize silage diets were 1·38 and 1·20 kg d^-1 respectively, but the differences were not significant (P> 0·05).     

缩节胺、多效唑和矮壮素对向日葵生理特性的影响

为使用化控技术塑造合理株型,通过不同浓度缩节胺、多效唑和矮壮素对食用向日葵生理特性分析,研究植物调节剂对向日葵生理特性影响以及合理的施用量。以新食葵7号为材料,将喷施缩节胺、多效唑和矮壮素设置5个不同处理浓度,研究不同浓度的植物生长调节剂下向日葵叶绿素、游离脯氨酸和可溶性蛋白含量、膜脂过氧化以及保护性酶活性的变化规律。不同浓度植物生长调节剂对向日葵的各生理指标影响不同,缩节胺200mg/L、多效唑100mg/L和矮壮素12g/L提高向日葵叶片的叶绿素和可溶性蛋白含量、增加游离氨基酸的积累量、降低丙二醛的产生、增强SOD、POD、CAT保护酶活性,提高植株的生理代谢功能。     

The influence of the growth season on the antimicrobial and antioxidative activity in Artemisia princeps var. orientalis

We investigated the influence of the growth season of Artemisia princeps var. orientalis (P_AMPAN.) H_ARA on antimicrobial and antioxidative activities. The ethyl acetate and water fractions of crude methanol extract from the plant collected monthly (April through October) were tested against three gram-positive, two gram-negative bacteria and one lactic acid bacterium. The ethyl acetate and water fractions of crude methanol extract from A. princeps var. orientalis collected in August and September had the highest antimicrobial activity. The antimicrobial activity of extract from A. princeps var. orientalis for Lactobacillus plantarum was not found at any concentration and in any growth season. Minimum inhibitory concentration (MIC) for each strain by ethyl acetate fraction of methanol extract from A. princeps var. orientalis was different depending on the tested strain and growth season of the plant. MIC for each strain was the highest in the sample from April, followed by October. The antioxidative activities of methanol extracts from A. princeps var. orientalis collected monthly were measured by their scavenging activity on free radical of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and xanthine oxidase (XO) inhibitory activity. The DPPH radical scavenging activities of the extracts from the plants collected in May, June and July were higher than any other. The XO inhibitory activities of the extracts of A. princeps var. orientalis collected in April and May showed the greatest activity, it is different with antimicrobial activity. This is the first report that antimicrobial and antioxidative activity of the extracts of A. princeps var. orientalis is different with growth season.     

The effect of stage of perennial ryegrass maturity at harvesting, fermentation characteristics and concentrate supplementation, on the quality and intake of grass silage by beef cattle

Abstract Two experiments were carried out in consecutive years to examine the influence of cutting date and restricting fermentation by carboxylic acid treatment on the nutrient intake from grass silage by beef cattle. In year 1, four cutting dates during July and August after a primary growth harvest and, in year 2, five cutting dates of primary growth between mid‐May and early July were examined. Herbage was ensiled either untreated or treated with high levels of acid additive (‘Maxgrass’, mean 8·6 l t^?1). Ninety‐six (year 1) or forty‐eight (year 2) continental cross steers were used in partially balanced changeover design experiments with each silage type either unsupplemented or supplemented with 4·5 (year 1) or 5·5 (year 2) kg concentrates head^?1 d^?1. Silage digestibility declined significantly between initial and final harvest dates (P < 0·001), whereas silage dry‐matter (DM) and digestible energy (DE) intakes were significantly higher in the initial compared with final harvest dates in both years of the study (P < 0·01). Similarly, silage DM and DE intakes, and total DM intakes, of acid‐treated and unsupplemented silages were greater than those of untreated and concentrate supplemented silages, respectively (P < 0·001). The results indicate that earlier cutting dates, and addition of acid to herbage before ensiling, can increase silage DM intake by beef cattle.     

Investigation of the effect of cupric chloride on thermal stabilization of polyamide 6 as carbon fiber precursor

An investigation on the role of cupric (Cu²⁺) ion incorporation during the thermal stabilization of polyamide 6 fibers was carried out using a combination of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) measurements. Cupric chloride pretreated and thermally stabilized polyamide 6 (PA6) fibers was characterized by a reduction in fiber diameter and linear density values together with color changes from light brown to black with increasing stabilization time. PA6 fibers were properly stabilized after 8 h of stabilization time prior to carbonization. The results obtained from DSC and TGA measurements indicated that there was an improvement in the thermal stability when cupric (Cu²⁺) ions were incorporated into the polymer structure. TGA thermograms showed the relative improvement in thermal stability as indicated by increasing char yield with progressing time. Char yield reached a maximum value of 33.6 % at 1000 °C for the cupric chloride pretreated PA6 fibers stabilized for 12 h at 180 °C. Experimental results obtained from DSC and X-ray diffraction methods suggested the loss of crystallinity as a result of perturbation of hydrogen bonds with progressing time. The formation of cupric ion-amide coordination bonds improved the thermal stabilization by encouraging the development of ladder-like structures. The investigation resulted in a new method of evaluation of X-ray stabilization index specifically intended for the thermally stabilized PA6 fiber.     

The mineral metabolism of sheep fed high- and low-magnesium selections of Italian ryegrass

Two experimental populations of Italian ryegrass selected for high and low magnesium content were established as swards, harvested fresh daily and offered to sheep. Chemical analysis of the crops showed a 44% higher Mg and a 22% higher Ca concentration in the high-Mg selection but no significant differences between the selections for the other minerals.
Blood and rumen contents were sampled throughout the feeding period and voluntary intake, digestibility and mineral balances for Na, K, Mg, Ca and P were determined. Magnesium intake, apparent availability and retention were significantly greater with the high-Mg selection. There were no significant differences in the plasma-mineral concentrations and all were within the normal range. Rumen fluid from animals fed the high-Mg selection had a higher proportion of soluble Mg and a higher Na:K ratio in the supernatant liquor.     

Studies on the effect of curry leaves supplementation (Murraya koenigi) on lipid profile,glycated proteins and amino acids in non-insulin-dependent diabetic patients

Curry leaves powder supplementation (12 g providing 2.5 g fibre) was carried out for a period of 1 month in 30 non-insulin dependent diabetes mellitus patients. The parameters monitored at 1, 15 and 30 days were fasting and 2 h post-prandial blood sugar levels, serum total cholesterol and its lipoprotein fractions, triglycerides, total amino acids, uronic acid, glycosylated serum proteins and glysocylated low density lipoprotein cholesterol fraction. The results indicated a transient reduction in fasting and post-prandial blood sugar levels at 15-day period with no appreciable changes in serum glycosylated protein levels, glycosylated low density lipoprotein cholesterol fraction, serum lipids, lipoprotein cholesterol levels, uronic acid and total amino acids were observed during the supplementation period, i.e. either at 15 days or 30 days.     

The effects of dietary fibre addition on the quality of common cereal products

Cereal products are consumed daily by the majority of the population. Popular belief is that these cereal products, rich in carbohydrates, produce a high glycaemic response and may not be a contributing factor to the obesity epidemic throughout the world. Recently the food industry has investigated ways of improving the overall nutritional balance of carbohydrate rich foods and focused on increasing their dietary fibre (DF) contents at the expense of readily digestible carbohydrates. It is well documented that dietary fibre is involved in disease prevention and enhanced health of consumers. Moreover, the food industry can take advantage of the physicochemical properties of fibre to improve the viscosity, texture, sensory characteristics and shelf-life of their products. The focus of this review paper is on the influence of DFs (inulin, fructo-oligofructose, β-glucans, arabinoxylans and resistant starch) supplementation on the quality and nutritional aspects of common foods containing cereals- pasta, bread, muffins/cakes and extruded snacks. This review reports on the evidence regarding fibre enrichment of cereal foods and looks at the advances and future trends in enriched dietary fibre cereal products.     

日本的大豆生产历史和现状概况

根据在日本合作研究期间收集的有关日本大豆生产、研究资料整理而成,从日本近百年来的大豆生产情况、日本食用大豆的利用情况、日本大豆的进口情况、日本大豆的主要生产地区、日本的大豆新品种选育及配套栽培技术的研究、日本国产大豆需求趋势等方面分析了日本的大豆生产历史和现状.     

The nutritional evaluation of Italian ryegrass cultivars fed as silage to sheep and cattle

Three feeding trials with big bale silage were carried out to determine whether previously established intake differences between artificially dried Italian ryegrass cultivars could be repeated under differing conditions of food preparation and presentation. The silage was prepared in 2 consecutive years from the same field crop and fed to groups of cattle in both years. The second year silage was also fed to sheep indoors. All animals were fed ad libitum and the voluntary intakes recorded for groups of cattle and individual sheep. Chewing activity was also recorded on all groups of sheep.
The chemical composition of the two cultivars as fresh grass was similar in 1984 but there were small differences in 1983 with Tarquin showing slightly higher organic matter digestibility (DOMD) and lower dry matter and water-soluble carbohydrate compared to RvP. The only consistent differences in silage composition between cultivars was a slightly higher level of modified acid detergent (MAD) fibre in RvP compared to Tarquin. Despite these small differences the voluntary intake of cattle fed Tarquin was 19% higher than RvP in the first year and 35% in the second, while sheep showed a similar difference of 40% with the second year silage.
Recording of jaw activity with sheep showed that animals spent 40% more time eating and 27% more time ruminating RvP than Tarquin per unit of food eaten. This suggested that the intake differences, which were independent of digestibility, were related to the physical resistance of the feed to breakdown by chewing. These differences depend on the structural characteristics of the plants and were associated with differences in leaf/stem ratios and MAD-fibre content. These are less likely to be affected by the method of conservation or feed presentation and, although the degree of difference between the cultivars changed with the different procedures, the inherently higher intake of Tarquin persisted.