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Growth Hormone Secretagogue (A233) Improves Growth and Changes the Tissue Fatty Acid Profile in Juvenile Tilapia (Oreochromis niloticus) 下载免费PDF全文
Rebeca Martínez Carmen Morales Amilcar Arenal Antonio Morales Fidel Herrera Víctor González Mario Pablo Estrada 《Lipids》2018,53(4):429-436
Growth hormone (GH) release is a process that is well regulated by several factors, including GH secretagogues. GH can mediate the regulation of the fatty acid level and composition. The aim of this study was to determine the effect of a synthetic GH secretagogue peptide (A233) on the growth and fatty acid composition in tilapia (Oreochromis niloticus). To address this objective, we administrated a diet supplemented with A233 to juvenile tilapia for 60 days. The group fed with a diet supplemented with 600 μg of A233 per kg of feed increased in weight (4.81 ± 0.09 g) and specific growth rate (2.49 ± 0.03%/day) compared to the control diet group (3.63 ± 0.08 g, 2.07 ± 0.04%/day; respectively) (p < 0.001). In the muscle, the total lipids for the control diet group were higher than that in the group fed with 600 μg of A233 per kg feed; however, no differences were detected in the liver. In both tissues, the patterns of fatty acid composition and content were generally similar, with some exceptions. Tilapia fed with 600 μg of A233 per kg of feed showed, in liver and muscle, a significantly higher composition and content of n‐3 polyunsaturated fatty acids (such as 20:5n‐3, 22:5n‐3, 22:6n‐3) and n‐3/n‐6 PUFA than animals fed with the control diet. To our knowledge, this is the first report on the the effects of natural or synthetic GH secretagogues (GHS) on fatty acid composition, implying an increase in the nutritional quality of the tilapia. 相似文献
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A 20-week feeding trial was conducted to determine whether increasing linolenic acid (18:3n-3) in vegetable oil (VO) based
diets would lead to increased tissue deposition of 22:6n-3 in Nile tilapia (Oreochromis niloticus). Five isonitrogenous and isoenergetic diets were supplemented with 3% of either linseed oil (LO), a mixture of linseed oil
with refined palm olein oil (PO) (LO–PO 2:1) and a mixture of refined palm olein oil with linseed oil (PO–LO 3:2) or with
fish oil (FO) or corn oil (CO) as controls. The PO–LO, LO–PO and LO diets supplied a similar amount of 18:2n-6 (0.5% of diet
by dry weight) and 0.5, 0.7 and 1.1% of 18:3n-3, respectively. Increased dietary 18:3n-3 caused commensurate increases in
longer-chain n-3 PUFA and decreases in longer-chain n-6 PUFA in the muscle lipids of tilapia. However, the biosynthetic activities
of fish fed the LO-based diets were not sufficient to raise the tissue concentrations of 20:5n-3, 22:5n-3 and 22:6n-3 to those
of fish fed FO. The study suggests that tilapia (O. niloticus) has a limited capacity to synthesise 20:5n-3 and 22:6n-3 from dietary 18:3n-3. The replacement of FO in the diet of farmed
tilapia with vegetable oils could therefore lower tissue concentrations of 20:5n-3 and 22:6n-3, and consequently produce an
aquaculture product of lower lipid nutritional value for the consumer. 相似文献
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以罗非鱼鱼皮为原料,研究利用酶法制备胶原蛋白肽制品。测定了罗非鱼皮的基木组成成分,利用低温连续相变萃取技术进行脱脂处理;以水解度、水解产物分子量和感官评定为指标,研究蛋白酶种类对酶解的影响;以水解度为指标,研究酶解条件对水解度的影响,并采用响应面试验对鱼皮胶原肽制备工艺进行优化;用凝胶过滤色谱法测定酶解液分子质量分布。结果表明:采用碱性蛋白酶水解鱼皮效果最好,酶解的最佳工艺条件为:时间7 h、加酶量7%、温度60℃、pH值10.38,在此条件下碱性蛋白酶水解罗非鱼皮的水解度最高可达23.01%。由本法所得胶原肽是以分子质量180~1000 u之间的寡肽(约2~8个氨基酸残基)为主的物质,具有较好的生理活性,可作为功能因子广泛应用于保健食品、化妆品、医药等各个行业当中。 相似文献
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罗非鱼下脚料蛋白合成类蛋白反应的工艺优化 总被引:1,自引:0,他引:1
以罗非鱼下脚料为原料,采用Alcalase蛋白酶对其进行控制酶解,制备不同水解度的罗非鱼下脚料酶解蛋白,在此基础上添加胃蛋白酶对其进行合成类蛋白反应的研究。以类蛋白产率为指标,在反应温度恒定(37℃)的条件下,通过单因素实验,确定底物水解度为40%、反应时间24h,选取底物浓度、加酶量和pH值3个因素进行响应面实验,通过响应面分析法优化合成类蛋白反应的最佳工艺组合为:底物浓度44.16%,加酶量4.12%,pH值5.08;在此条件下,类蛋白产率达到(10.08±0.03)%,与响应面二次模型预测值(10.11%)无显著差异。 相似文献
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Red hybrid tilapia (Oreochromis sp.) were fed one of four diets containing either fish oil, crude palm oil, palm fatty acid distillates or refined palm olein as the only added oil. Post-harvest fillet quality was then evaluated at 1, 10 and 30 weeks of frozen storage. Dietary oil source did not significantly (p > 0.05) influence the liquid holding capacity and texture of fillets but both these parameters were increased by frozen storage. Fillets from fish fed palm oil-based diets exhibited significantly higher oxidative stability during frozen storage, compared to fish fed the fish oil diet. Dietary oil source and frozen storage had little impact on sensory attributes. Unlike fillet proximate composition, fillet fatty acid composition was significantly affected by both diet and frozen storage. Total n-3 polyunsaturated fatty acids decreased significantly in the fillet lipids of all fish after 30 weeks of frozen storage. 相似文献
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以罗非鱼加工鱼片的下脚料鱼头、鱼骨、鱼尾等为原料,选用弹性蛋白酶对其水解,通过响应面进行分析并优化酶解条件.以水解度与多肽含量为指标,分别对酶浓度、温度、pH值、料液比、酶解时间等因素对弹性蛋白酶酶解罗非鱼下脚料水解效果的影响进行分析.结果表明,弹性蛋白酶水解罗非鱼加工下脚料的最佳条件为:酶浓度0.553 mg/g,料液比1:5、自然pH、温度41.94 ℃、酶解3.31 h,在此条件下得到的水解度为18.09%,多肽含量为0.9 mg/mL. 相似文献
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响应面法优化罗非鱼鱼皮胶原多肽螯合镁的工艺条件的研究 总被引:1,自引:0,他引:1
以罗非鱼鱼皮为原料,研究鱼皮胶原多肽和镁离子的螯合工艺条件.探讨了鱼皮胶原多肽与氯化镁的质量比、反应体系的pH、螯合温度、螯合时间等因素对鱼皮胶原蛋白螯合反应的影响;在单因素实验的基础上,通过响应面法对鱼皮胶原多肽与镁的螯合工艺条件进行优化,确定最佳的螯合工艺条件为:质量比1∶5、pH7.0、螯合温度70℃、螯合时间30min.在此条件下,螯合率达84.58%.通过对比螯合反应前后傅里叶变换红外光谱图的变化,证明了鱼皮胶原多肽与镁离子形成了新的螯合物. 相似文献