南北接力养殖对皱纹盘鲍营养成分的影响

鲍的南北接力养殖是我国的一种常见养殖模式,旨在提高南方鲍鱼在夏季的存活率。鲍鱼通常在4月份从中国南方运至北方,11月返回南方。本实验探讨了这种模式对皱纹盘鲍营养成分的影响。测定方法主要依据GB 5009系列。研究样品于2017年12月采样,为相同饵料喂养(龙须菜)的商品鲍。两组鲍分别为全年于南方养殖(连江)的皱纹盘鲍和南北接力养殖的皱纹盘鲍。结果发现,两组鲍足肌中灰分、胶原蛋白、粗脂肪和糖原含量并没有显著差异,但南北接力组(水分:76.50%WW,蛋白质48.40%DW)相比于全年于南方养殖组(水分:73.70%WW,蛋白质:56.80%DW)有较高的水分含量和更低的蛋白质含量。矿物质含量方面,全年于南方养殖的皱纹盘鲍(0.07 mg/100g)足肌中硒的含量高于南北接力养殖组(0.05 mg/100 g)。呈味氨基酸方面,南北接力养殖方式下的皱纹盘鲍,其足肌谷氨酸、牛磺酸、精氨酸、赖氨酸和呈味氨基酸总量显著低于全年南方养殖组。脂肪酸方面,两组鲍有相似的脂肪酸组成,但南北接力养殖组的脂肪酸营养价值较高。研究表明,南北接力养殖模式对皱纹盘鲍的营养成分既有积极影响,又有消极影响,但总体上看差别并不显著。     

长岛皱纹盘鲍产业现状与发展对策研究

溯源长岛鲍鱼增养殖历史,分析产业现状,从种质、栖息地生境、产业化和品牌化建设四个方面查摆制约因素,并针对性提出政产学研金协同推动皱纹盘鲍(Haliotis discus hannai)种质保护和持续发展,建立长岛皱纹盘鲍标准体系,推进长岛皱纹盘鲍种业发展,推动皱纹盘鲍资源快速恢复,推进皱纹盘鲍生态养殖产业发展,加快品牌建设和宣传推介,加强资金保障的对策建议。     

液熏鲍冷风干燥工艺优化及贮藏期的研究

为提高鲍鱼的附加值,研发干制液熏鲍新产品,以确定液熏鲍干燥最优工艺参数及贮藏时间。以液熏鲍为研究对象,采用冷风干燥技术干制液熏鲍。在单因素试验基础上,通过响应面设计试验,以冷风干燥温度、干燥风速和干燥时间为因素,对干制熏鲍的硬度和弹性变化情况进行研究并建立相关数学模型,确定液熏鲍冷风干燥的加工工艺;同时探讨干制熏鲍的安全指标及保藏性。结果显示,由模型方程确定液熏鲍鱼冷风干燥工艺的最优参数为:温度26℃,风速4 m/s,时间23 h。在此条件下干制熏鲍的硬度为(22 845.05±1 098.71)N,弹性为(-0.13±0.03)mm。经该工艺生产的干制熏鲍,各项指标均符合国家食品安全标准和商业无菌要求,并且具有较好的风味和品质。     

基于DEB理论的皱纹盘鲍个体生长模型参数的测定

为获取皱纹盘鲍(Haliotis discus hannai)个体生长模型所需的6个关键参数，设计了饥饿耗能、温度对耗氧的影响等相关生理实验，计算得到各项参数值。单位体积维持耗能率的值 、形成单位体积结构物质所需的能量值 、单位体积最大储存能量 和储备能量值 4个参数，通过连续测定皱纹盘鲍饥饿过程中呼吸耗氧率和软组织干重不断下降直至保持稳定时的能量值计算；温度函数中Arrhenius温度 的数值根据皱纹盘鲍在不同温度梯度下的单位干重耗氧率测定、计算；形状系数δm值通过统计测量的壳长、软组织湿重等生物学参数拟合回归得到。结果显示，皱纹盘鲍在饥饿后，呼吸耗氧率和软组织干重分别降低了26.3%和70.0%，呼吸耗氧率由2.69 mg/(ind.?h)逐渐降低并稳定在0.8 mg/(ind.?h)，软组织干重由(5.21±0.89) g降低至(3.84±0.22) g；根据公式计算得 和 的值分别为20.18 J/(cm3?d)和8120 J/cm；皱纹盘鲍饥饿前后有机物含量分别为80%和58%，经过换算， 和 的值分别为2726 J/cm3和32583 J/g。不同规格的皱纹盘鲍在水温为5℃~20℃范围内，温度与单位干重耗氧率呈正比；当水温超过20℃之后，温度与单位干重耗氧率呈反比。在转折点20℃之前，单位干重耗氧率的ln值与温度(热力学温度，K)的倒数呈线性关系，线性回归方程斜率的绝对值为Arrhenius温度 值( =7196 K)。生物学统计分析鲍壳长(L)与体积(V)呈三次函数关系：V=0.0639 L3.1621(R²=0.9852)，根据公式对软组织湿重的立方根与壳长进行线性回归，所得的斜率即为形状系数δm值(δm=0.43)。本研究对建立以DEB理论为指导的皱纹盘鲍个体生长模型提供了数据支撑。     

皱纹盘鲍染色体C带和rDNA定位

为了提高对皱纹盘鲍染色体的辨识水平,实验利用 Ba(OH)₂ 处理显示了皱纹盘鲍染色体的C带,并用荧光原位杂交分析(fluorescence in situ hybridization,FISH)研究了核糖体大亚基rDNA在皱纹盘鲍中期染色体上的数目与位置。核型结果显示,皱纹盘鲍染色体组包含7对中部着丝粒染色体和8对亚中部着丝粒染色体,另有3对染色体介于中部着丝粒染色体与亚中着丝粒染色体之间(m/sm)。C显带结果显示,8对染色体有稳定的着丝粒C带,5～7对染色体上有中期相间多态的端部C带,3对染色体上有同源染色体异态的臂间C带。FISH 分析显示,皱纹盘鲍中期染色体上分布着4个大亚基 rDNA位点,分别位于2号短臂(2S)、7号短臂(7S)、12号短臂(12S)和18号长臂(18L)的端部。研究结果为皱纹盘鲍染色体辨识提供了新的特征与标记,为进一步研究皱纹盘鲍种群的染色体多态和鲍属染色体进化提供了基础资料。     

鲍鱼海上养殖技术探讨

鲍鱼是爬附在浅海低潮线以下岩石上的一种单壳类软体动物。我国南方以养殖盘鲍与皱纹盘鲍的杂交品种黑鲍为主,也有九孔鲍等其他鲍鱼。1鲍鱼养殖的海区选择鲍鱼海上养殖应选择在无工业＂三废污染＂的海区放养,其水质应符合NY5052技术标准的要求。并在潮流畅通,流速1～3m/s,流向平直稳定的海区放养     

辽宁鲍鱼资源现状与增殖途径

鲍鱼是珍贵海产软体动物。主要分布在太平洋北部及印度洋东南部，经济价值较高的有二十种。分布在我国广东、福建、台湾、浙江、山东及辽宁沿海的有三种。在南海、东海分布的，为杂色鲍(H．diversivolor R．)及耳鲍(H．asinina L．)；在黄海水域辽宁、山东沿岸分布的为皱纹盘鲍(H．discus hanai Ino)(本文简称鲍鱼)。     

皱纹盘鲍与绿鲍杂交种生长比较

为探明皱纹盘鲍(Haliotis discus hannai)与绿鲍(Haliotis fulgens)种间杂交的受精、孵化和苗种发育规律,对皱纹盘鲍和绿鲍进行种间杂交,检测了不同组合受精率和孵化率,并以同期培育的皱纹盘鲍与绿鲍种间杂交F1(DF)、自繁F1(DD、FF)及回交F1(DD×DF、DD×FD)为研究对象。在相同养殖条件下,本文对皱纹盘鲍与绿鲍杂交、回交后代的生长、存活差异及相应的优势进行研究,为进一步探讨皱纹盘鲍与绿鲍的杂交效果、准确评价杂种优势提供理论依据。     

温度胁迫对皱纹盘鲍生理和生化活动的影响

为探讨温度胁迫下皱纹盘鲍(Haliotis discus hannai Ino)的响应机制,采用室内控温实验,通过设置4个温度梯度(5℃、10℃、20℃和25℃),设计温度骤变处理组(皱纹盘鲍从15℃暂养温度直接转移至各实验温度)和温度缓变处理组(0.5℃/12 h),分析温度剧烈变化和温度缓慢变化对皱纹盘鲍耗氧率和排氨率的影响及其差异性;并对高温和低温处理下皱纹盘鲍消化腺中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、酸性磷酸酶(ACP)和溶菌酶(LSZ)活性的变化情况以及不同组织(血细胞和肌肉组织)中Cu/Zn–SOD基因的表达状况进行了研究。结果表明,皱纹盘鲍耗氧率和排氨率随海水温度的升高而增加,20℃达到最高值;25℃骤变处理组与缓变处理组耗氧率和排氨率间存在极显著差异(P0.01)。5℃和10℃骤变处理组皱纹盘鲍氧氮比(O/N)同缓变处理组间存在极显著差异(P0.01)。在高温胁迫后的3 h,消化腺中SOD、CAT和LSZ活性达到最高,而ACP活性在胁迫6 h后达到最高(P0.01);低温胁迫显著降低皱纹盘鲍LSZ的活性,于胁迫9 h后达到最低(P0.01)。不同温度胁迫下,皱纹盘鲍血细胞和肌肉组织中Cu/Zn–SOD基因的相对表达量均表现上调,与对照组存在显著差异性(P0.05)。本研究表明,温度胁迫能显著影响皱纹盘鲍的生理和生化活动,这将有助于探讨皱纹盘鲍夏季高死亡率的原因,为皱纹盘鲍健康养殖提供一定的理论依据。     

贝类养殖技术之五南方地区皱纹盘鲍育苗技术

皱纹盘鲍为我国鲍属中的优势种,主要分布于我国辽宁、山东沿海,属耐寒不耐高温品种。近年来,由于日本盘鲍(黑鲍)抗病力、商品价值(2006年市场差价40元左右/公斤)明显逊色于皱纹盘鲍,南方地区各育苗场开始引进皱纹盘鲍进行苗种培育及养成。笔者于2004年~2006年在平潭县上井海珍品开发有限公司对皱纹盘鲍秋季培育、繁殖及人工育苗进行了比较深入的研究,并取得较好的市场效果与经济效益,特将南方地区皱纹盘鲍育苗技术总结如下。一、育苗场设施育苗场交通便利,进排水设施完善,具沙井20口,过滤池1口(面积200m2),室内培养池200m3,培育池规格6m×3.…     

Optimization of Hydrolysis Conditions for Production of Angiotensin-Converting Enzyme Inhibitory Peptides from Basa Fish Skin Using Response Surface Methodology

ABSTRACT

Basa fish skin free from fat and noncollagenous proteins was hydrolyzed by different proteinases to produce angiotensin-converting enzyme (ACE) inhibitory peptides. Protamex hydrolysates were found to have the highest ACE inhibitory activity. Response surface methodology (RSM) was applied to optimize the hydrolysis conditions of Protamex—including enzyme-to-substrate ratio, hydrolysis time, and solid (fish skin)-to-liquid (water for hydrolysis)—at a temperature of 50°C and a pH of 7.0. The mathematical model demonstrated a good fit with the experimental data. An enzyme-to-substrate ratio of 6,108 U/g, a hydrolysis time of 1.24 h, and a solid-to-liquid ratio of 1:8.05 g/mL were found to be the optimal conditions to achieve the highest value of ACE inhibitory activity. The IC₅₀ of the hydrolysates for ACE inhibitory activity was 1.417 mg/mL under these conditions.     

Influence of spoilage and processing temperature on the quality of marine fish protein sources for salmonids

Press cake meals were prepared from previously frozen herring immediately following thawing and after storage for 8 or 12 days at 2-5°C. Each of the raw sources of herring was subjected to two processing temperatures, 75°C and 100°C, during meal preparation. Also, protein hydrolysates were prepared using ocean perch when fresh or after storage at 2-5°C for 4 or 8 days. Subsequently, each of the three hydrolysates was dried at 85°C or 93°C. In two separate experiments, each of the herring press cake meals and dried perch protein hydrolysates was blended with a reference diet in a 30:70 ratio (test protein source: reference diet). All diets contained 5 g kg^?1 chromic oxide as an indigestible marker. The reference diet and all test diets were provided to satiation to chinook salmon in salt water and rainbow trout in fresh water, with digestibility of organic matter, protein and energy measured by difference. Digestibility of protein was also measured by the pH-stat and dilute pepsin solubility in vitro techniques. The results indicated that variation in processing temperature to a maximum of 100°C had little effect on digestibility of marine fish protein sources. By contrast, raw material storage for 8 days or more at 2-5°C prior to processing was found to reduce organic matter digestibility and sometimes nitrogen digestibility in salmonids. In vitro measures of digestibility were of little help in predicting the nutritive value of the test protein sources. Cadaverine level in herring press cake meal was shown to be a good indicator of spoilage in the raw material.     

Angiotensin-converting enzyme I inhibitory activity of phlorotannins from Ecklonia stolonifera

ABSTRACT:   As part of our study of the isolation of antihypertensive agents derived from natural marine products, the bioactivity of 10 edible Korean seaweeds were screened by angiotensin converting enzyme (ACE) inhibitory and peroxynitrite assays. Among the crude extracts of selected seaweeds, including five Phaeophyta ( Ecklonia stolonifera , E. cava , Pelvetia siliquosa , Hizikia fusiforme , and Undaria pinnatifida ), four Rhodophyta ( Gigartina tenella , Gelidium amansii , Chondria crassicaulis , and Porphyra tenera ) and one Chlorophyta ( Capsosiphon fulvescens ), the ethanol extracts of E. stolonifera , E. cava , P. siliquosa , U. pinnatifida , and G. tenella exhibited significant inhibitory properties against ACE at more than 50% inhibition at a concentration of 163.93 µg/mL. Phloroglucinol 1 , eckstolonol 2 , eckol 3 , phlorofucofuroeckol A 4 , and dieckol 5 had been isolated previously, and triphlorethol-A 6 and fucosterol 7 were isolated for the first time from E. stolonifera. Also, the ACE inhibitory and peroxynitrite scavenging properties of phlorotannins 1–6 were evaluated, along with fucosterol 7 obtained from E. stolonifera . Among profound peroxynitrite scavenging compounds 1–6 , phlorotannins 3 , 4 and 5 were also determined to manifest marked inhibitory activity against ACE, with 50% inhibition concentration (IC₅₀) values of 70.82 ± 0.25, 12.74 ± 0.15, and 34.25 ± 3.56 µM, respectively.     

An evaluation of open and closed systems for in vitro protein digestion of fish meal

The availability of a rapid, cost-effective, accurate and reliable method of assessing fish meal protein digestibility would greatly enhance and standardize quality-control procedures in both the fish meal and fish feed industries. However, while several in vitro digestibility tests have been developed, few have been adopted by industry due to their time-consuming nature, problems surrounding reliability and/or inconsistencies in predictive ability. The present investigation was undertaken to evaluate the utility and predictive qualities of two in vitro digestion assays of distinct design. Methods examined included a novel open system, wherein on-line removal of digestion products was attainable, and a closed system, which permitted analysis of products following completion of the digestion process. Results provided by the two systems were compared using four differentially processed fish meals. The open system supplied information based upon the detected quantity of products below 10 kDa. The closed system provided measurement of free amino groups. Both methods were in agreement with respect to assessing the presence of hydrolysed product. Both systems furnished complementary data with respect to the characterization of fish meal protein quality. The closed and open systems provided insight upon digestibility and digestion kinetic profiles respectively.     

热塑挤压蒸煮对鱼肉蛋白质营养价值的影响初探

采用胃蛋白酶—胰酶复合处理法对原料鱼肉、蒸煮和罐藏处理的鱼肉产品,以及热塑挤压蒸煮的鱼肉制品进行蛋白质体外消化率的测定,分析比较各种鱼肉制品的蛋白质体外消化率的测试结果;结果表明,挤压蒸煮对鱼肉蛋白质的消化率有一定的影响。     

Utilization of Shrimp By-Products by Bioconversion with Medical Fungi for Angiotensin I-Converting Enzyme Inhibitor and Antioxidant

ABSTRACT

A liquid fermentation process to bioconvert shrimp by-products was developed with two species of fungi, Boletus edulis and Suillus bovinus. Angiotensin I-converting enzyme (ACE) inhibitory, antioxidant activities of bioconverted products and the deodorization effect of fungal bioconversion were determined. Two species of fungi could grow quickly in shrimp by-products medium and deodorize shrimp by-products. Bioconverted products had higher ACE inhibitory and antioxidant activities than control medium. Water extracts without crude polysaccharides from mycelia of B. edulis had the highest ACE inhibitory activity (IC₅₀ = 0.084 ± 0.011 mg/mL). Crude exopolysaccharides of B. edulis had higher antioxidant activity. Bioconversion with the fungus was proven to be a novel, practicable way to recycle shrimp by-products.     

Digestibility and growth performance of juvenile rainbow trout (Oncorhynchus mykiss) fed with pea and canola products

A digestibility experiment and subsequent 84-day feeding experiment evaluated the use of pea and canola meal products in diets for rainbow trout. The effect of milling and heat treatment on nutrient, dry matter and energy digestibility of raw/whole peas, raw/dehulled peas, extruded/dehulled peas and autoclaved air-classified pea protein was determined. Digestibility of the protein component was uniformly high for all pea ingredients (90.9–94.6%), regardless of the processing treatment. Autoclaving or extrusion increased starch digestibility by 41–75% ( P  ≤ 0.05), which consequently increased energy and dry matter digestibility of whole and dehulled peas. Autoclaved air-classified pea protein had superior protein (94.6%), energy (87.0%) and dry matter (84.0%) digestibility ( P  ≤ 0.05). It was demonstrated that inclusion of 25% dehulled peas, 20% air-classified pea protein or 20% canola meal fines was feasible in trout diets allowing for replacement of soya bean meal. The data showed no difference ( P  ≥ 0.05) in feed intake, final weight and specific growth rate (SGR) measurements, and feed utilization was not compromised with inclusion of pea or canola meal products as the primary plant ingredient. It was concluded that dehulled peas, air-classified pea protein and canola meal fines are suitable ingredients for use in trout diet formulation at a level of 20%.     

饲用血粉的新生产工艺及采用膨化血粉喂养试验的效果

饲用血粉的生产从采用干燥工艺，发酵工艺，到采用喷雾干燥工艺，都存在产品的可消化率偏低的问题，并涉及诸如生产环境和耗能过大等问题，本校采用专门研制的连续膨化设备对含有一定水分的碎血块进行连续瞬时加工，经进一步粉碎后，制成了新型饲用血粉－膨化血粉，其体外消化率达９７．６％。用含有膨胀化血粉的配合饲料喂养淡水鱼类的平均饲料系数为１．７９。利用膨化血粉和喷雾血粉对ＡＡ肉鸡进行对比喂养试验表明，两组的平均饲     

鲍鱼冷风干燥和自然晾晒试验的比较分析

研究皱纹盘鲍(Haliotis discus hannai Ino)在冷风干燥和自然晾晒两种干燥方式下的干燥速率、色泽、酸性粘多糖和总糖含量,以及微观结构变化的差异,并进行分析比较。在实验室内采用冷风干燥试验机和自然晾晒方式进行鲍鱼干燥试验。结果显示:当鲍鱼样品干基含水率从238%下降到16%以下时,冷风干燥所需时间约为122 h,是自然晾晒的70%;至干燥完成时冷风干燥鲍鱼多糖含量高于自然晾晒样品;冷风干燥样品通透性明显优于晾晒样品;两种干燥样品的微观结构差异性不明显。综合分析得出,与自然晾晒相比,冷风干燥方式具有干燥时间短,干燥过程易于控制,品质和卫生条件好,适合工业化生产等优点,是一种较佳的鲍鱼干制方法。