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991.
Valerio F de Candia S Lonigro SL Russo F Riezzo G Orlando A De Bellis P Sisto A Lavermicocca P 《Journal of applied microbiology》2011,111(1):155-164
Aims: To evaluate the positive influence of the probiotic strain Lactobacillus paracasei LMGP22043 carried by artichokes into the human gut with special reference to faecal bacterial balance, short‐chain fatty acid concentrations and enzyme activities in a randomized, double‐blind human trial in comparison with probiotic‐free artichokes (control). Methods: Twenty subjects were randomized into two groups, which consumed daily 180 g of the artichoke product (probiotic or control) during two 15‐day study periods (periods 1 and 2) separated by a 15‐day washout in a crossover manner. Faecal samples were subjected to microbiological and biochemical analyses, and a strain‐specific PCR was performed to monitor the probiotic strain. Results: The probiotic strain, transported by the vegetable matrix, transiently colonized the gut of 17/20 subjects (median 6·87 log CFU g?1 faeces), antagonized Escherichia coli and Clostridium spp. and increased the genetic diversity of lactic population based on REP‐PCR profiles, mainly after period 1. Conclusions: The probiotic L. paracasei LMGP22043 successfully colonized the human gut and positively influenced faecal bacteria and biochemical parameters. Significance and Impact of the Study: The association of the probiotic L. paracasei with a food carrier rich in fibre can represent a new strategy for favouring a daily supply of probiotics and attracting more consumers to vegetable food fortified with probiotic strains. 相似文献
992.
Aims: To determine structure–function relationships of antibacterial phenolic acids and their metabolites produced by lactic acid bacteria (LAB). Methods and Results: Minimum inhibitory concentrations (MICs) of 6 hydroxybenzoic and 6 hydroxycinnamic acids were determined with Lactobacillus plantarum, Lactobacillus hammesii, Escherichia coli and Bacillus subtilis as indicator strains. The antibacterial activity of phenolic acids increased at lower pH. A decreasing number of hydroxyl groups enhanced the activity of hydroxybenzoic acids, but had minor effects on hydroxycinnamic acids. Substitution of hydroxyl groups with methoxy groups increased the activity of hydroxybenzoic, but not of hydroxycinnamic, acid. Metabolism of chlorogenic, caffeic, p‐coumaric, ferulic, protocatechuic or p‐hydroxybenzoic acids by L. plantarum, L. hammesii, Lactobacillus fermentum and Lactobacillus reuteri was analysed by LC‐DAD‐MS. Furthermore, MICs of substrates and metabolites were compared. Decarboxylated and/or reduced metabolites of phenolic acids had a lower activity than the substrates. Strain‐specific metabolism of phenolic acids generally corresponded to resistance. Conclusions: The influence of lipophilicity on the antibacterial activity of hydroxybenzoic acids is stronger than that of hydroxycinnamic acids. Metabolism of phenolic acids by LAB detoxifies phenolic acids. Significance and Impact of the Study: Results allow the targeted selection of plant extracts for food preservation, and selection of starter cultures for fermented products. 相似文献
993.
目的:探讨胃癌围手术期能量及营养物质的代谢特点,研究强化胰岛素治疗对围手术营养代谢的影响。方法:选取胃中、下部癌病理诊断明确并且外科病房ICU住院时间不少于24h的患者64例,取得知情同意后随机分到强化胰岛素治疗(IIT)组血糖控制在4.4~6.1mmol/L,和传统治疗(CIT)组血糖控制在10mmol/L以下;应用CCM营养代谢监测系统测定围手术期静息能量消耗(REE),呼吸商(RQ),每公斤体重静息能量消耗(REE/kg)和脂肪氧化比率,应用多频人体生物电阻抗分析仪测定围手术期人体组分的变化及应用稳态模式评估法计算胰岛素抵抗指数(HOMA-IR)。结果:64例病人入选,每组32例,手术创伤引起术后第1、3天REE水平增加约22%和12%,呼吸商降低至0.759和0.791,REE/kg增加28kcal/kg和26kcal/kg,脂肪氧化比率增加至78%和65%,Ln-HOMA-IR明显增加(P〈0.05);IIT治疗能降低术后第1、3天Ln-HOMA-IR和REE/kg水平;术后人体指标如细胞内液、脂肪组织、蛋白组织、肌肉组织、瘦体组织和体质量较术前水平明显降低(P〈0.05);IIT能明显减少脂肪组织、蛋白组织和细胞内液的消耗量(P=0.009,t=0.026)。结论:IIT能够有效降低胃癌围手术期胰岛素抵抗程度、降低静息能量消耗的水平和减少脂肪及蛋白质的消耗。 相似文献
994.
Mosnier E van der Werf HM Boissy J Dourmad JY 《Animal : an international journal of animal bioscience》2011,5(12):1972-1983
The incorporation of feed-use (FU) amino acids (AAs) in diets results in a reduced use of protein-rich ingredients such as soybean meal, recognized to have elevated contributions to environmental impacts. This study investigated whether the incorporation of L-lysine.HCl, L-threonine and FU-methionine reduces the environmental impacts of pig and broiler feeds using Life Cycle Assessment. The following impact categories were considered: climate change, eutrophication, acidification, terrestrial ecotoxicity, cumulative energy demand and land occupation. Several feeds were formulated either to minimize the cost of the formulation (with or without AA utilization), to maximize AA incorporation (i.e. the cost of AA was considered to be similar to that of soybean meal), or to minimize greenhouse gas emissions. For both pig and broiler feeds, calculations were made first using only cereals and soybean meal as main ingredients and then using cereals and several protein-rich ingredients (soybean meal, rapeseed meal and peas). In addition, these calculations were performed using two types of soybean meal (from Brazil, associated with recent deforestation or not). For broiler feeds, two types of maize (from France, irrigated, with mineral fertilization v. not irrigated, with animal manure fertilization) were also tested. Regarding the feeds formulated to minimize cost, incorporation of AA decreased the values for eutrophication, terrestrial ecotoxicity and cumulative energy demand of both pig and broiler feeds, regardless of the base ingredients. Reduction in climate change and acidification due to the incorporation of AA depended on the nature of the feed ingredients, with the effect of AA incorporation being greater when combined with ingredients with high impacts such as soybean meal associated with deforestation. Feeds formulated to maximize AA incorporation generally had a similar composition to those formulated to minimize cost, suggesting that the costs of AA were not the limiting factor in their incorporation. Feeds formulated to minimize greenhouse gas emissions had the lowest values for climate change and cumulative energy demand, but not for other impacts. Further research is needed to elucidate whether the incorporation of additional AA (tryptophan and valine) along with L-lysine, L-threonine and FU-methionine could decrease on the environmental impacts of pig and broiler feeds further. 相似文献
995.
Zhanar A. Kozhamkulova Mohamed M. Radwan Galiya E. Zhusupova Zharilkasin A. Abilov Samir A. Ross 《Phytochemistry letters》2011,4(3):323-327
Halimodendrin I, a new acylated triterpene glycoside (1), was isolated and chemically characterized as 3β-O-palmitoyl-28-[3′-palmitoyl-β-d-glucopyranosyl]-olean-12-en-28-oic acid from the aerial part of Halimodendron halodendron (Fabaceae) by IR, 1D and 2D NMR, HR-ESI-MS and LR-ESI-MS experiments. In addition, seven known compounds were isolated and identified as: palmitic acid, glycerol-2-linoleneate, glycerol-1,3-dilinoleneate, ferulic acid, 3-O-methylquercetin, β-sitosterol, and β-sitosterol-3-O-β-d-glucopyranoside. Nine fatty acids were identified and quantified in the saponifiable matter of the hexane extract. These fatty acids are: myristic, n-pentadecanoic, palmitoleic, palmitic, linoleic, oleic, stearic, arachidic, and behenic acids. The volatile oil was isolated by hydrodistillation (0.013%, w/w) with unpleasant smell. Twenty-seven components were identified in the oil by GC/MS. 相似文献
996.
Gjerlaug-Enger E Kongsro J Aass L Odegård J Vangen O 《Animal : an international journal of animal bioscience》2011,5(11):1829-1841
This study was conducted to evaluate the potential of near-infrared (NIR) spectroscopy (NIRS) technology for prediction of the chemical composition (moisture content and fatty acid composition) of fat from fast-growing, lean slaughter pig samples coming from breeding programmes. NIRS method I: a total of 77 samples of intact subcutaneous fat from pigs were analysed with the FOSS FoodScan NIR spectrophotometer (850 to 1050 nm) and then used to predict the moisture content by using partial least squares (PLS) regression methods. The best equation obtained has a coefficient of determination for cross-validation (CV; R(2)(cv)) and a root mean square error of a CV (RMSECV) of 0.88 and 1.18%, respectively. The equation was further validated with (n = 15) providing values of 0.83 and 0.42% for the coefficient of determination for validation (R(2)(val)) and root mean square error of prediction (RMSEP), respectively. NIRS method II: in this case, samples of melted subcutaneous fat were analysed in an FOSS XDS NIR rapid content analyser (400 to 2500 nm). Equations based on modified PLS regression methods showed that NIRS technology could predict the fatty acid groups, the main fatty acids and the iodine value accurately with R(2)(cv), RMSECV, R(2)(val) and RMSEP of 0.98, 0.38%, 0.95 and 0.49%, respectively (saturated fatty acids), 0.94, 0.45%, 0.97 and 0.65%, respectively (monounsaturated fatty acids), 0.97, 0.28%, 0.99 and 0.34%, respectively (polyunsaturated fatty acids), 0.76, 0.61%, 0.84 and 0.87%, respectively (palmitic acid, C16:0), 0.75, 0.16%, 0.89 and 0.10%, respectively (palmitoleic acid, C16:1n-7), 0.93, 0.41%, 0.96 and 0.64%, respectively (steric acid, C18:0), 0.90, 0.51%, 0.94 and 0.44%, respectively (oleic acid, C18:1n-9), 0.97, 0.25%, 0.98 and 0.29% (linoleic acid, C18:2n-6), 0.68, 0.09%, 0.57 and 0.16% (α-linolenic acid, C18:3n-3) and 0.97, 0.57, 0.97 and 1.22, respectively (iodine value, calculated). The magnitude of this error showed quite good accuracy using these rapid methods in prediction of the moisture and fatty acid composition of fat from pigs involved in breeding schemes. 相似文献
997.
The first limiting nutrients in typical laying hen diets are the sulphur-containing amino acids and, in particular, methionine. To fulfil the birds' recommended requirement, conventional diets are supplemented with synthetic methionine. As this is not allowed in organic production it becomes very important to have access to alternative high-quality protein feed ingredients. An experiment was performed to evaluate the possibility to compose a diet with 100% organically approved feed ingredients using mussel meal as a major source of methionine. The experiment included 678 Lohman Selected Leghorn (LSL) and 678 Hyline White, W-98, layers during 20 to 72 weeks of age. There were 12 aviary pens with 113 birds in each. The birds were fed one of the two experimental diets containing either 3.5% or 7% dried mussel meat meal or a commercial organic diet from a Swedish feed manufacturer for comparison. Production and mortality were recorded daily per group, and egg weight was recorded once weekly. At 33, 55 and 70 weeks, 10 eggs from each treatment group were collected and analysed for internal egg quality. Diets had no significant effect on laying percentage, egg mass, feed intake, feed conversion ratio, mortality, bird live weight or proportion misplaced, cracked or dirty eggs. Egg quality, that is, shell deformation, shell breaking strength, albumen height, shell percentage and proportion of blood and meat spots were also unaffected. There was a significant difference in egg yolk pigmentation, that is, the egg yolk was more coloured when feeding 7% mussel meal compared with the other diets. Hyline hens had lower feed intake and laying percentage, and higher egg weight, but lower egg mass production than LSL birds. The age of the birds influenced all egg quality traits except for meat and blood spots. The dry matter of the excreta was significantly lower for both genotypes fed the 7% mussel meal diet. These results indicate that mussels may be a high-quality protein source and may replace fishmeal in organic diets for layers. 相似文献
998.
999.
1000.