大豆小肽的营养及其在水产养殖中的应用

近年来,小肽作为一种绿色饲料添加剂逐渐成为研究的热点。大豆小肽是大豆蛋白质水解后产生的由几个到几十个氨基酸残基组成的肽混合物,能对动物的生理功能产生直接影响。小肽作为蛋白质的主要消化产物,在氨基酸消化、吸收以及动物营养代谢中起着重要的作用。在水产养殖中,添加适量的小肽可增强水产动物的免疫力,提高养殖成活率、饲料中各种矿物元素的利用率、饲料转换率、体内蛋白质的合成能力以及养殖过程中的增重率,促进鱼类的生长。一、大豆小肽的营养大豆是一种优良的植物蛋白资源,其中含有35%的粗蛋白,经过加工而成的大豆饼粕含有42%左…     

大豆蛋白活性肽培育淡水鱼种试验

大豆蛋白活性肽是以大豆蛋白为原料将产酶菌种经特殊发酵工艺所生产的一种低分子肽混合物。它具有以下几种特性:①活性肽是一种分子肽混合物,含有大豆蛋白酶解的小肽,还有产酶菌发酵分子的小肽及其代谢产物。②活性肽的氨基酸平衡良好,作为蛋白源吸收率     

大豆小肽在鲫鱼鱼苗中的应用

大豆是一种优良的植物蛋白资源,其中含有35％的粗蛋白,经过加工而成的大豆饼粕含有42％左右的粗蛋白,而且必需氨基酸丰富平衡,因此是动物日粮中最常用的蛋白质饲料。但是其中也含有多种抗营养因子,使用不当,不仅会造成营养价值下降,而且会危害动物健康。大豆小肽是大豆蛋白质水解产物产生的由几个到几十个氨基酸残基组成的肽混合物,     

大豆小肽蛋白替代鱼粉对黄颡鱼幼鱼生长性能、消化酶活性和抗氧化功能的影响

为研究大豆小肽蛋白替代鱼粉对黄颡鱼(Pelteobagrus fulvidraco)生长性能、体成分、消化酶活性和抗氧化功能的影响,以30%鱼粉组为对照组(A0),大豆小肽蛋白分别替代17%、33%和50%的鱼粉作为实验组(A17、A33和A50),配制4种等氮配合饲料。每组设置4个重复,每个重复饲喂30尾平均体重为(3.7±0.6) g的黄颡鱼幼鱼,进行为期80 d的饲养实验。结果显示,A17组生长性能与对照组无显著差异(P>0.05),A33组除增重率(WGR)显著高于对照组外(P<0.05),其余指标均与对照组无显著差异(P>0.05)。A50组饵料系数(FCR)显著高于对照组和其他实验组(P<0.05),增重率、特定生长率(SGR)及蛋白质效率(PER)显著低于对照组和其他实验组(P<0.05)。各实验组肥满度(CF)和脏体比(VSI)与对照组无显著差异(P>0.05)。大豆小肽蛋白替代鱼粉对黄颡鱼全鱼水分、灰分和粗蛋白含量无显著影响(P<0.05);然而,当大豆小肽蛋白替代鱼粉水平从33%升高至50%时,鱼体粗脂肪含量显著降低(P<0.05)。各实验组肠脂肪酶和肠淀粉酶活性显著高于对照组(P<0.05),A33和A50组胃淀粉酶显著高于对照组(P<0.05)。大豆小肽蛋白替代鱼粉对黄颡鱼肝胰脏丙二醛(MDA)活性无影响。综上所述,黄颡鱼配合饲料中鱼粉替代量小于33%时,黄颡鱼生长性能最佳,且对鱼体肝脏抗氧化功能无不利影响。本研究首次探究大豆小肽蛋白替代鱼粉对黄颡鱼生长等的影响,以期为黄颡鱼饲料配制和大豆小肽蛋白的使用等提供参考。     

介绍一种蛋白饲料原料——高赖氨酸活性蛋白饲料

众所周知，近年来饲料原料紧缺，尤其是优质蛋白饲料原料．如鱼粉等资源越来越少，为此必须寻找新的优质蛋白饲料原料替代鱼粉等优质蛋白原料。高赖氨酸活性蛋白为最新研制的高科技优质蛋白原料．利用生物技术将大豆等植物蛋白降解为小肽。并将植物蛋白的抗营养物质彻底分解，同时使植物细胞壁100％破解，     

高效液相色谱法测定大豆秸杆中大豆异黄酮的含量

通过对大豆黄酮液相色谱检测条件和大豆秸杆中大豆异黄酮的提取、净化、浓缩方法的优化,建立一套适应浙江省衢州市实际情况的大豆秸杆中大豆异黄酮含量检测方法,并检测了衢州市野生及常规品种的大豆秸杆中大豆异黄酮的含量。结果表明:利用反相液相色谱法对乙酸乙酯提取的大豆秸杆中大豆异黄酮进行直接检测,提取效率高,无杂质干扰,检测成本低廉适合于推广普及。衢州市野生及常规品种的大豆秸杆中大豆黄酮和染料木素的含量相差不大,为837.7⁹55.3μg/g。     

海洋鱼、虾、贝类的生物活性肽研究进展

肽与蛋白质是海洋生物中含量极其丰富的生理活性物质,近年来的研究表明,海洋生物活性肽具有特殊的生理活性,诸如免疫、抗肿瘤、抗高血压、抗血脂、抗菌和促生长等生理活性。本文就鱼类活性肽中的鲨肝肽、鲨鱼多肽、鱼精蛋白肽、鱼类抗菌肽、鱼类抗高血压肽,虾类活性肽以及贝类中的扇贝多肽和贻贝肽的生物活性研究概况作一简述。为该领域研发海洋保健食品和功能性食品提供参考。     

蛋白质营养的新阶段:肽营养

动物蛋白质营养研究已进入一个新的阶段:肽营养阶段。肽作为蛋白质代谢的中间产物具有的重要的作用。肽营养理论是国内外营养学家研究的热点之一。从肽的吸收特点、吸收机制,肽的营养与生理作用,影响肽释放、吸收和利用的因素及饲料蛋白源活性肽的开发应用等方面阐述了当前动物肽营养的研究进展。     

鱼类肽YY与胰肽Y的研究进展

酪酪肽与胰肽Y同属于胰多肽家族,是广泛存在的多功能调节肽;胰肽Y是酪酪肽基因组复制产生的鱼类中特有的神经肽。目前已在多种鱼类中分离得到酪酪肽与胰肽Y的基因,与特定受体发挥生理功能,包括使机体产生饱腹感而食欲下降,减少摄食,降低体质量,在调控养殖鱼类摄食,提高饲料转化率,促进鱼类健康养殖以及消化道、肝胰腺、肥胖等治疗方面发挥重要作用。本文通过概述鱼类中酪酪肽与胰肽Y的结构特征、体内分布、作用的形式及受体、影响因素等生物学功能,为鱼类肽YY及胰肽Y的研究提供参考。     

小肽营养研究进展

小肽是由二或三个氨基酸残基构成的二肽或三肽,是蛋白质降解为氨基酸过程的中间产物,其营养作用不容忽视。对单胃动物、反刍动物小肽的吸收机制及特点、小肽的营养生理作用、影响小肽营养的因素等方面进行阐述。同时对小肽的应用前景作出展望。     

Apparent digestibility of soybean coproducts in extruded diets for Nile Tilapia,Oreochromis niloticus

Soybean coproducts are important protein sources in aquaculture because of their amino acid profile. Tilapia can be reared on soybean coproducts as the only source of dietary protein without compromising growth. This study estimated apparent digestibility coefficients for five soybean coproducts for juvenile Nile tilapia, Oreochromis niloticus, fed with extruded diets. A reference diet and test diets consisting of 70% reference diet and 30% coproduct ingredient were formulated, along with 5.0 g kg^?1 chromic oxide (Cr₂O₃) as a marker. Apparent digestibility coefficients (ADC) for dry matter (ADCDM), gross energy (ADCGE) and crude protein (ADCCP) for soybean coproducts were estimated as 84.2–88.4%, 86.9–91.1% and 96.8–97.9%, respectively. ADCDM and ADCCP values did not vary among the ingredients, but low‐protein soybean meal exhibited lower ADCGE values than did soybean protein concentrate. ADCs of all amino acids were >95%, and mean ADCs for amino acids were similar to the values observed for ADCCP. Soybean coproducts had good nutritional value in extruded diets fed to tilapia. Methionine, histidine and valine were the limiting amino acids in all evaluated ingredients.     

大豆胰蛋白酶抑制剂微生物发酵灭活研究

采用乳酸菌、枯草芽胞杆菌发酵大豆粉,均能有效消除、灭活大豆中胰蛋白酶抑制剂的活性。乳酸菌发酵未加乳酸菌培养基的大豆粉,乳酸菌接种量为5%、10%时,胰蛋白酶抑制剂的活性灭活优于15%的菌种接种量;枯草芽胞杆菌发酵大豆粉,菌种接种量为5%时,胰蛋白酶抑制剂的活性灭活优于菌种接种量为10%、15%。     

不同饲料对南京丰年虫生长和生殖的影响

用豆浆、米糠、酵母3种饲料培养南京丰年虫(Chirocephalus nankinensisShen),试验结果表明:这3种饲料对南京丰年虫生长和生殖力的影响差异显著。其中,体长和体重增长依次为豆浆>酵母>米糠,成活率高低顺序为米糠>豆浆>酵母;生殖力高低顺序为豆浆>米糠>酵母。故用豆浆为饲料培养南京丰年虫较适于其生长和种群的增殖。     

Inhibition of protease activities in discus Symphysodon spp. by three plant meals

Based on biochemical assays and electrophoretical methods, the inhibitory effects of three plant meals (soybean meal, wheat meal, winged bean meal) on digestive alkaline proteases of discus were investigated. Casein assays revealed that increasing levels of soybean meal caused a linear inhibitory effect on activity of protease. SDS-PAGE images revealed that trypsin and chymotrypsin were the inhibited enzymes. Soybean showed the lowest inhibition rate followed by wheat meal and raw winged bean. There was a quadratic relationship between wheat meal levels and its inhibition of protease acitivity. The highest inhibitory effect was obtained with the winged bean meal with inhibition of caseinolytic activities ranging from 3.6–98.6%. Results from this study showed the potential of both soybean meal and wheat meal as ingredients for practical diet for discus, while demonstrating the need for further improvement in processing method for winged bean meal.     

大豆分离蛋白的机能特性及其应用

通过对大豆分离蛋白的溶解性、保水性、乳化性、起泡性、吸油性、凝胶形成性的研究,讨论温度、浓度、pH值对大豆分离蛋白的功能特性的影响,为大豆分离蛋白的进一步应用提供了理论依据,并指出了可应用的方向。     

Effects of different soybean proteins on lipid digestion and growth of yellowtail <Emphasis Type="Italic">Seriola quinqueradiata</Emphasis>

Two experiments were conducted to determine whether the undigested high molecular fraction (HMF) of soybean protein reduces growth of yellowtail through impairment of lipid digestion and absorption. Soybean meal (SBM), soy protein isolate (SPI), digested SPI (DSPI), and digested and purified SPI (DPSPI) were used as experimental diets. In experiment 1 (exp. 1), yellowtail were fed 4 diets with aforementioned soybean products for 3 weeks. In experiment 2 (exp. 2), the fish were fed soybean protein or fish meal (FM) diets for 8 weeks. Growth performance of DPSPI-fed fish was better than that of fish fed other soybean proteins, and comparable to that of fish fed with FM. Plasma and tissue lipid levels of DPSPI-fed fish tended to be higher than those of fish fed other soybean proteins. Significantly lower intestinal lipid levels and higher bile acid levels were found in DPSPI-fed fish than in fish fed with SBM, SPI, and DSPI. These findings indicate that one of the factors contributing to growth depression in yellowtail fed with SBM-based diets is the negative effect of undigested HMF of soybean protein on bile acid levels and lipid digestion.     

Growth response and fatty acid composition of rainbow trout (Oncorhynchus mykiss) fry fed diets containing different levels of soybean and egg lecithin

We investigated the effect of soybean and chicken egg lecithin on the growth performance, fatty acid profile and body composition of rainbow trout fry. Seven isonitrogenous and isolipidic diets were prepared by replacing 0, 2, 4 and 6 % soybean and egg lecithin instead of soybean oil in diets. Trout fry with initial average weight 120 ± 4.08 mg were randomly distributed in twenty-one 90-L tanks. Triplicate groups (165 fish per tank) of fry were fed to visual satiation at six meals per day for 40 days. Incorporation of 2 and 4 % egg lecithin led to increase in final weight, specific growth rate and weight gain compared with control group. Also, 4 % soybean lecithin had moderate effects on growth performance of fry. The fatty acid compositions of fry were influenced by dietary fatty acid. Fish fed egg lecithin showed higher amount of monounsaturated fatty acid than soybean lecithin and control groups. Fry fed soybean lecithin had significantly higher levels of polyunsaturated and n-6 fatty acid than egg lecithin and control groups. Soybean and egg lecithin induced higher amount of highly unsaturated fatty acid in lecithin groups compared with control group. The lipid and ash content of whole-body tissues were positively affected by percentages of soybean and egg lecithin in the diets. So 6 % soybean and egg lecithin induced higher amounts of lipid and ash body content. The results of our study indicated that dietary egg lecithin had growth-promoting effect, and rainbow trout fry had moderate lecithin requirement (at least 2 % as fed).     

Effect of soybean-meal-based diets on the growth and survival rate of the Indian major carp, Cirrhinus mrigala (Ham.)

The effect of varying dietary levels of defatted soybean meal on the growth and survival of mrigal, Cirrhinus mrigala (Hamilton) was investigated. In a feeding trial of 90 days, three experimental diets containing soybean meal at 200, 300 and 400 g kg^?1 level of incorporation were fed to quadruplicate groups of 10 fish each. The conventional feed used in India, consisting of a mixture of groundnut oil cake and rice bran in 1 : 1 ratio served as the control. Best growth in terms of percentage weight gain, specific growth rate, protein efficiency ratio (PER), feed conversion ratio and survival rate was obtained for the test diet with 354 g kg^?1 crude protein and with 400 g kg^?1 soybean meal inclusion level. However, no statistical significant difference was observed between the three soybean‐based diets, except for PER and survival rate. Soybean meal is an easily available, acceptable and cost‐effective protein source in formulated feeds for Indian major carps. The results of the present study indicate that a diet of 350 g kg^?1 overall protein with soybean meal included at 400 g kg^?1 can elicit good growth response and survival in mrigal.     

Soybean molasses as an organic carbon source in the farming of Litopenaeus vannamei (Boone, 1931) in a biofloc system

Soybean molasses was evaluated as a partial replacement for sugarcane molasses as a carbon source for biofloc development in the superintensive culture of Pacific white shrimp (Litopenaeus vannamei). A 50‐day study was conducted with juvenile (3.2 g) shrimp stocked in 16 800 L tanks at a stocking density of 250 shrimp m^?3. Control of total ammonia concentration was performed by the addition of combined mixtures of soybean and sugarcane molasses to the culture water. Three different molasses treatments were evaluated using different soybean‐to‐sugarcane molasses ratios: 15–85%, 38–62% and 60–40% respectively. The control group was treated only with sugarcane molasses. Water quality, chlorophyll a concentration, heterotrophic bacterial load, Vibrio spp. concentration and zootechnical indexes were all evaluated. Total ammonia concentration was controlled by heterotrophic and chemotrophic pathways. Biofloc formation, as quantified by measuring the total suspended solids, was not altered. The Vibrio spp. concentration showed a significant reduction in treatments with soybean‐to‐sugarcane molasses ratios of 38–62% and 60–40%. All combined mixtures of soybean and sugarcane molasses could maintain water quality and productivity in the superintensive culture of L. vannamei using the biofloc system. Thus, the potential use of a residue from agroindustry as a carbon source in a biofloc culture is demonstrated.     

Gene expression responses to restricted feeding and extracted soybean meal in Atlantic salmon (Salmo salar L.)

We assessed effects of feed restriction and inclusion of 200 g kg^?1 extracted soybean meal in the diet on gene expression in Atlantic salmon using a cDNA microarray (SFA2.0) and real‐time qPCR. The trial lasted for 54 days. Restricted feeding and soybean inclusion reduced the thermal growth coefficient by respectively 51% and 22% compared with fish fed with the fishmeal‐based control diet to satiation. Soybean decreased distal intestinal expression of lysosomal (cathepsins C, D, L, Y and Z) and extracellular proteases while genes involved in responses to cellular stress were up‐regulated. Expression changes of immune genes suggested both pro‐ and anti‐inflammatory regulation. The hepatic responses to soybean and restricted feeding were highly similar, which could be because of negative effects of soybean meal on digestion and nutrient absorption. We observed up‐regulation of ribosomal proteins and down‐regulation of genes involved in lipid and steroid metabolism. Of note, growth reduction in both study groups was associated with coordinated down‐regulation of genes involved in oxidative and cellular stress responses, metabolism of xenobiotics and protein degradation. High expression of stress‐related genes in salmon fed with the control diet suggests that maximum growth rates can be associated with health problems.