Fatty acid and proximate composition of bluefin tuna (Thunnus thynnus) muscle with regard to plasma lipids

The composition of tail muscle fatty acids from wild and cultured bluefin tuna reared on a diet based on herring and sardine, along with the plasma lipid profile of the farmed individuals, was determined. The total lipid content of farmed bluefin in this study was 0.922 g/100 g or 3.49 g of saturated fatty acids (SAFA), 4.48 g of monounsaturated fatty acids (MUFA), 2.58 g polyunsaturated fatty acids (PUFA) n‐3 and 0.37 g of PUFA n‐6 fatty acids; for wild specimens, it was 0.920 g/100 g, or 2.85 g of SAFA, 4.82 g of MUFA, 2.78 g PUFA n‐3 and 0.27 g of PUFA n‐6 fatty acids. The major fatty acids in this study were 16:0; 16:1, n‐7; 18:1, n‐9 and DHA 22:6, n‐3 acids. The sum of these major components accounted for more than 57% and 80% of the total fatty acids in all the samples of farmed and wild tuna respectively. No significant differences in the proximate composition were demonstrated between farmed and wild samples, except for the energy value, in favour of the farmed tuna. Statistically, glucose tends to increase together with cholesterol (CHOL) and plasma triglyceride, as for these pairs, it showed positive correlation coefficients and P>0.05. Some measured tuna metabolites demonstrated strong mutual correlations, especially GLU, CHOL and TRIG, which are crucial factors in the lipid profile of animals.     

Live prey first feeding regimes for short‐snouted seahorse Hippocampus hippocampus (Linnaeus, 1758) juveniles

As with many species of seahorses, Hippocampus hippocampus wild populations are being subjected to uncontrolled exploitation in their natural environment. Thus, aquaculture could contribute to satisfy the commercial demand for animals while promoting the recovery of wild stocks. The present study was conducted to compare the effect of the substituting Artemia nauplii with rotifers for first feeding seahorse juveniles. Survival, growth and biochemical composition of prey organisms and fish were studied during the feeding trial. In addition, to help the biometric study, an anaesthetic test was also carried out using clove oil. The results showed excellent survival (average 60%) in juveniles exclusively fed with Artemia, with better values than those reported previously obtained by other authors for this species. By comparison, high mortality and poor growth were observed during first feeding with seahorses fed on rotifers. This could have been related to the lower energy intake and poorer nutritional value of the rotifers. Furthermore, clove oil concentrations of 25 ppm were found to work well as an anaesthetic for seahorse juveniles. Overall, first feeding Artemia alone was found to be an efficient and simplified method for feeding young H. hippocampus fry, building the principles for their culture for ornamental or re‐stocking purposes.     

功能性脂质稳定性的乳液物理调控研究进展

食品功能性脂质多存在不溶于水和氧化稳定性差等缺点,采用油水界面技术制备乳液作为功能性脂质的载体,可提高功能性脂质的稳定性和生物利用度,扩大其在食品领域的应用。食品胶体结构复杂,分子构象多种多样,形成的界面结构对功能性脂质的化学稳定性有重要影响。从决定乳液结构和性质的乳化剂种类、乳液颗粒粒径分布、界面吸附特性等方面综述了乳液体系对功能性脂质稳定性的影响,为设计基于食品胶体乳液技术的功能性脂质载体提供理论支持。     

大气温室效应与植物的光合性状──大气CO_2浓度升高对油桐和烟草光合气体交换及叶的脂类组成的影响

在大气ＣＯ２体积分数为７００×１０－６条件下，对油桐和烟草的光合ＣＯ２同化速率、光呼吸１８Ｏ２吸收速率、光合色素、叶的脂类和脂肪酸组成等进行了比较分析．结果表明：大气ＣＯ２体积分数为７００×１０－６时油桐和烟草的光合速率有所增加，并抑制光呼吸１８Ｏ２的吸收，但是，油桐对ＣＯ２浓度升高比烟草敏感，它的光合速率在７００×１０－６ＣＯ２时增加了２倍，而光呼吸１８Ｏ２吸收则完全消失；油桐在７００×１０－６ＣＯ２下生长，光合色素合成量增加较多，其中叶绿素ｂ及类胡罗卜素等属于捕光色素系统的色素增加尤其明显，叶绿素ａ／ｂ值显著下降，在同样条件下，烟草的叶绿素含量还略有减少，类胡罗卜素含量则明显减少；高浓度ＣＯ２影响这两种植物叶的脂类和脂肪酸的组成，７００×１０－６ＣＯ２下生长的这两种植物叶的饱和脂肪酸和磷脂含量有所增加，但油桐叶的糖脂含量有所下降，烟草的糖脂含量则不受ＣＯ２浓度升高的影响．     

Variation of wheat grain lipid fraction and its antioxidative status under the impact of delayed sowing

This study determined the profile of hydrophobic phytochemicals (steroid-like components and lipophilic phenolics) and antioxidant potential (DPPH and Rancimat tests) of wheat grain in relation to sowing date (standard vs. delayed) using six cultivars of Triticum aestivum wheat grown in Poland. The study found that “sowing time” generally had a low impact on sterols, carotenoids, squalene and total lipophilic phenolics in wheat grain. The highest impact of “sowing time” was noted for α-tocopherol, C19:0 alkylresorcinol and campesterol. Delayed sowing reduced their content by up to 9%. The antioxidant potential of grain extracts obtained by the use of water-saturated butanol (WSB) was mostly cultivar-dependent (depending on assay: DPPH 56.3% and Rancimat 75.1% of explained variation, respectively). Wheat grain WSB extracts increased rapeseed oil induction time by up to 21% and their antioxidant capacity was up to 1.24 μM TEg⁻¹.     

日粮中添加屎肠球菌对AA肉鸡生产性能、免疫器官指数和血液脂质代谢相关指标的影响

本试验旨在研究日粮中添加屎肠球菌对AA肉鸡生产性能、免疫器官指数和血液脂质代谢相关指标的影响，探讨屎肠球菌替代抗生素在肉鸡日粮中应用的可行性及其最适添加量。试验选取1日龄AA肉鸡公仔鸡600只（50 g/只），随机分成5组，每组6个重复，每个重复20只鸡。对照组（CON）饲喂基础日粮；抗生素组（ANT）饲喂基础日粮+0.1%金霉素；3个屎肠球菌试验组（LEF、MEF和HEF组）在基础日粮中分别添加50、100、200 mg/kg屎肠球菌。试验分2期，分别为1~21日龄（前期）和22~42日龄（后期）。结果显示：①各试验组肉鸡生长性能与CON组相比均无显著差异（P>0.05）；从饲养全期看，MEF组和HEF组AA肉鸡的死淘率最低。②在饲养后期，与CON组相比，MEF组胸腺指数显著提高（P<0.05），MEF组脾脏指数有提高的趋势（0.05 < P < 0.1）。③在饲养前期，与CON组和ANT组相比，LEF组和HEF组血清总胆固醇（TC）含量极显著降低（P<0.01）；与ANT组相比，LEF组和MEF组血清甘油三酯（TG）含量极显著降低（P<0.01）；与CON组相比，MEF组和HEF组血清高密度脂蛋白（HDL）含量极显著提高（P<0.01）；与ANT组相比，添加屎肠球菌试验组的低密度脂蛋白（LDL）含量极显著降低（P<0.01）。在饲养后期，与CON组和ANT组相比，LEF组肉鸡血清中TG含量极显著降低（P<0.01），LEF组和MEF组HDL含量极显著提高（P<0.01）。综上所述，在肉鸡饲养中，添加屎肠球菌可以在一定程度上降低死淘率，并有促进免疫器官发育的趋势，还具有一定的降低血脂的作用。综合考虑，建议在AA肉鸡日粮中添加100 mg/kg屎肠球菌。     

Plasma Membrane Lipids Are the Powerful Components for Early Stage Aluminum Tolerance in Triticale

The order of aluminum (Al) tolerance in triticale lines (ST2>ST22) after re-elongation in an Al-free 0.2 mM calcium (Ca) solution for 9 h (Ca period) following 1 h pretreatment with 20 μM Al (Al period) agreed with that after 24 h of Al treatment. Permeability of the plasma membrane (PM) of root-tip cells after the Ca period was significantly increased in Al-sensitive ST22. Al was accumulated more heavily in the root-tip portion of ST22 than in that of ST2, although similar amounts of malic and citric acid anions were released from both triticale lines. We established a new system examining lipid permeability using synthesized nylon-2,8 ultrathin and porous capsules trapped previously with 0.1% (w/v) methylene blue solution and coated thereafter with PM lipid isolated from root tips by a newly developed technique. Permeability of the PM lipid measured with time in 0.2 mM Ca with or without 50 μM Al photometrically ( A ₆₈₀) was significantly greater in Al-sensitive ST22 after 5 min of Al treatment. This is the first report to directly show the primary and early role of PM lipid in Al tolerance in triticale.     

Inheritance of groat-oil content and high-oil selection in oats (Avena sativa L.)

Summary The potential for breeding for high groat-oil content in oats was investigated by (a) conducting generation means analyses on data from three matings among adapted Avena sativa L. cultivars, (b) practicing one cycle of phenotypic recurrent selection in a segregating population derived from eight species backcrosses (Avena sativa x (A. sativa x A. sterilis)) among 24 parents, and (c) identifying transgressive segregates from interspecific (A. sativa x A. sterilis) matings.Additive gene action was the most important component in explaining the variation among generation means for groat-oil content. Dominance and epistatic interactions involving dominance were not significant in any mating. Significant residual genetic variation occurred in one mating, even after additive, dominance, and three digenic interactions were fitted. The importance of additive genes action implies that desired allelic combinations for high groat-oil content can be obtained in pure-line cultivars.One cycle of phenotypic recurrent selection using single plants as the selection units resulted in a genetic gain of 1.7 to 2.1% in groat-oil content. Individual plants selected for initiating the second cycle had from 9.5 to 12.6% groat oil.Over all 12 interspecific matings, the F₂ progeny means were similar to the midparent values. Only two were significantly deviant. Transgressive segregates for high and low groat-oil content from these matings provided evidence that A. sterilis possesses alleles for high and low groat-oil content that are different from those in the gene pool of cultivated oats.Journal Paper No. J-11340 of the Iowa Agric. and Home ECon. Exp. Stn., Ames, Iowa 50011. Project 2447. This study was supported in parts by grants from the Iowa Committee for Agricultural Development and the International Harvester Company.     

日粮脂质对家兔肉品质的影响概述

家兔日粮中的脂质能够影响兔肉的品质,科学利用日粮脂质,能够克服兔肉多不饱和脂肪酸组成不平衡和易氧化的缺点,提高兔肉的营养价值和肉品质。文章简述了日粮脂质在兔肉中的蓄积及对兔肉脂肪酸成分、抗氧化性、系水力和嫩度的影响。     

Do changes in Atlantic salmon,Salmo salar L., fillet fatty acids following a dietary switch represent wash‐out or dilution? Test of a dilution model and its application

The fatty acid compositions of fish tissue lipids usually reflect those of the feed lipids, but few attempts have been made to predict the way in which the profiles change or assess the time required for the fatty acid profile to stabilize following a dietary change. The present focus on the influences of vegetable oils and fish oils on the fatty acid compositions and sensory attributes of fish fillets increases the interest in the ability to make such predictions. A dilution model was tested using data for the influences of feed oils (rape/linseed (V) vs. sand‐eel (F)) and dietary fat concentrations (ca. 30% (H) vs. ca. 20% (L)) on the body growth and fatty acid compositions of the fillets of Atlantic salmon, Salmo salar L., parr and post smolt. Fish given HV or LV feeds during freshwater rearing (mass increase from ca. 19 g to ca. 130 g) were switched to HF and LF feeds following parr–smolt transformation. The changes in fillet percentages of 18:1, 18:2 (n‐6) and 18:3 (n‐3) during 98 days of on‐growing in seawater (mass increase from ca. 130 g to ca. 380 g) conformed closely to predictions made on the basis of the dilution model. Model applications require information about the proportionate increase in fillet fat over time, but the relative changes in body mass can be used as a surrogate provided that both fillet yield (as a % of body mass) and fillet fat percentage change little over time. This is not the case for small salmon, but does seem to apply to larger salmon as they approach harvest size. This means that, for large salmon, ratios of changes in body mass can be substituted for ratios in the quantitative change in fillet fat without the introduction of a large error in the prediction of the change in fillet fatty acid profile following the introduction of a novel feed.