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寡聚糖在水产养殖上的应用 总被引：1，自引：0，他引：1
寡聚糖又称低聚糖或寡糖,是指由2～10个单糖通过糖苷键连接形成直链或支链的一类糖,分子通式一般可表示为(C6H10O5)n,n=2～10,分子量约为300～2000道尔顿,甜度一般只有蔗糖的30%～50%,由于单糖分子不同和单糖间的不同结合方式,形成了种类繁多的寡聚糖,已知有1000种以上。日本20世纪70年代开始寡聚糖开发研究,80年代批量生产异麦芽寡糖和果寡糖,90年代已开发70余种功能性寡糖。1994年日本生产的1/3寡聚糖用作饲料添加剂,40%的日本猪饲料中都添加了这类物质。目前寡聚糖在亚洲、加拿大、欧洲的生产和使用都呈上升势头。我国从90年代中后期才… 相似文献
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正寡糖又称为低聚糖或寡聚糖,是由2~10个单糖单位通过糖苷键连接而成的小聚合体。寡糖又分为普通寡糖和功能性寡糖两大类,常见的普通寡糖有蔗糖、麦芽糖、乳糖等,易于被动物消化吸收、产生能量;常见的功能性寡糖有果寡糖、甘露寡糖等,这类寡糖不易被动物消化吸收,但却有着特殊的生理功能。 相似文献
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功能性寡糖在水产养殖中的应用 总被引：1，自引：0，他引：1
寡糖（O ligo saccharide）又称低聚糖或寡聚糖,是由2个～10个单糖通过糖苷键连接形成的低度聚合糖类的总称。人们通常把寡糖看成是抗营养因子。20世纪60年代,日本首先将其应用于食品,作为免疫增强剂, 相似文献
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琼胶寡糖的制备及其_13_C_NMR研究 总被引：4，自引：0，他引：4
天然多糖酶降解是制备寡聚糖的一个重要途径。酶降解由于具有特异性 ,可选择性地酶解切断特定链 ,从而制得特定的寡聚糖 ,并且反应条件温和 ,降解过程易于控制 ,在多糖降解中运用日益增多。在对多种微生物筛选研究基础上 ,从一种海洋微生物中分离获得了对琼胶具有较高降解活性的琼胶酶 ,并将此琼胶酶应用于琼胶糖降解修饰研究。本文研究了琼胶寡糖的制备 ,并运用波谱分析对琼胶寡糖的结构进行研究 ,为琼胶的构效关系研究提供基础实验资料。1 材料与方法1 .1 琼胶糖的酶解取 5ｇ琼胶糖 ,加入 2 5 0ｍＬ蒸馏水并加热至 10 0℃摇动使其溶解 ,… 相似文献
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黑龙滩水库的底栖动物 总被引：3，自引：0，他引：3
黑龙滩水库底栖动物主要由寡毛类和水生昆虫组成。共检出底栖动物３５种（属），年均生物量６．５５５ｇ／ｍ＾２，密度１７６３个／ｍ＾２，每年提供的鱼产潜力为１０．９ｋｇ／ｈａ。 相似文献
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泥河水库底栖动物群落的研究 总被引：1，自引：0，他引：1
1997年对泥河水库进行资源调查，共获底栖动物4大类26种。其中软体动物14种，摇蚊幼虫6种，寡毛类5种，甲壳类1种。底栖动物的年平均密度为621.9个/m^2，生物量年平均为37.226g/m^2。阐述了底栖动物的季节变化、渔产潜力及底栖动物在环境检测中的作用。 相似文献
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2001年4月起对信阳南湾水库的底栖动物进行了周年定量采样调查。结果表明该水库底栖动物主要由水生昆虫和寡毛类组成，共检出底栖动物3种，年均生物量为0．6032克／平方米；密度为263．83个／m^2，每年提供的鱼产潜力为20034公斤。 相似文献
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自从1950年Stockstad报道在饲料中添加某种抗生素具有促生长效果以来,畜、禽、鱼饲料中添加抗生素日趋普遍.但长期使用抗生素后出现的负面效应,诸如药物残留,耐药苗株的产生,环境污染,以及二重感染等问题已倍受全球关注.美国、日本、比利时等国家逐渐加大对药物饲料添加剂的限制和监控;欧盟目前仅允许黄霉素、盐霉素、莫能霉素及卑霉素作为药物饲料添加剂,截止时间为2005年底.因而研制能改善畜禽健康、提高生产性能、无污染的安全无毒的饲料添加剂已成为一个开发热点.众多学者的研究表明,寡聚糖最有希望成为抗生素替代品之一[1].甘露寡糖(Mannan-oligosaccharides,MOS)便是众多寡聚糖中的代表. 相似文献
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低聚糖又称寡聚糖、寡糖,是由2-10个单糖通过糖苷键连接形成直链或支链的一类糖分子。由于组成低聚糖的单糖分子的种类以及连接单糖分子的糖苷键的类型不同,所以在自然界中低聚糖的种类达数千种以上。各种低聚糖在生物体内的功能是不相同的,根据低聚糖 相似文献
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Guangyu Wang Zhaoqi Meng Lei Chen Jiahui Jiang Yali Feng Bosong Zhang 《Aquaculture Research》2020,51(3):1133-1142
The kelp aquaculture production in China is the largest in the world, and a large amount of kelp residue is produced by kelp processing. Kelp residues contain substantial quantities of crude fibre, protein, and residual alginic acid, and may be used as feedstuff for aquaculture animals. In this study, we used probiotics to ferment kelp residues to improve kelp nutrient content and then fed the fermented kelp to the sea cucumber, Apostichopus japonicus. To study the effect of fermented feed on sea cucumber, its growth performance, digestive enzyme activity, diversity of intestinal microbiota and water quality of the sea cucumber culture water were determined. Growth performance of sea cucumber fed with fermented feed significantly (p < .01) increased when compared with sea cucumber fed with formulated feed. Amylase, cellulose and alginase activities were significantly (p < .01) higher in the fermented feed group when compared with the formulated feed group. The total number and diversity of intestinal microbiota showed a significant increase in sea cucumbers fed with the fermented feed. The water quality of the fermented feed group showed much lower ammonia and nitrite (<0.050 mg/L) levels when compared with the formulated feed group. These results suggest that kelp residues fermented with probiotics enhance the growth, digestive enzyme activities and intestinal microbiota of sea cucumbers and improve the culture water quality. Fermented kelp residues are a new supplementary nutrient source for sea cucumbers and may be applicable to other animal aquacultures. 相似文献
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三角褐指藻是一种单细胞蛋白,蛋白质含量丰富,质量好,动物易消化,并且三角褐指藻容易培养,生长速度快。本文旨在通过测定藻液中的主要营养指标蛋白质的变化,探讨三角褐指藻藻液的采收,研究三角褐指藻作为蛋白质饲料添加到饲料中的可能性,为饲料蛋白质提供新的来源。 相似文献
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P. De Schryver R. Crab T. Defoirdt N. Boon W. Verstraete 《Aquaculture (Amsterdam, Netherlands)》2008,277(3-4):125-137
The expansion of the aquaculture production is restricted due to the pressure it causes on the environment by the discharge of waste products in the water bodies and by its dependence on fish oil and fishmeal. Aquaculture using bio-flocs technology (BFT) offers a solution to both problems. It combines the removal of nutrients from the water with the production of microbial biomass, which can in situ be used by the culture species as additional food source. Understanding the basics of bio-flocculation is essential for optimal practice. Cells in the flocs can profit from advective flow and as a result, exhibit faster substrate uptake than the planktonic cells. The latter mechanisms appear to be valid for low to moderate mixing intensities as those occurring in most aquaculture systems (0.1–10 W m− 3). Yet, other factors such as dissolved oxygen concentration, choice of organic carbon source and organic loading rate also influence the floc growth. These are all strongly interrelated. It is generally assumed that both ionic binding in accordance with the DLVO theory and Velcro-like molecular binding by means of cellular produced extracellular extensions are playing a role in the aggregation process. Other aggregation factors, such as changing the cell surface charge by extracellular polymers or quorum sensing are also at hand. Physicochemical measurements such as the level of protein, poly-β-hydroxybutyrate and fatty acids can be used to characterize microbial flocs. Molecular methods such as FISH, (real-time) PCR and DGGE allow detecting specific species, evaluating the maturity and stability of the cooperative microbial community and quantifying specific functional genes. Finally, from the practical point of view for aquaculture, it is of interest to have microbial bio-flocs that have a high added value and thus are rich in nutrients. In this respect, the strategy to have a predominance of bacteria which can easily be digested by the aquaculture animals or which contain energy rich storage products such as the poly-β-hydroxybutyrate, appears to be of particular interest. 相似文献
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A. Colorni 《Aquaculture (Amsterdam, Netherlands)》1985,46(3):263-266
A practical dilution method for determining the degree of susceptibility of aquatic Vibrio and Aeromonas spp. to antibacterial agents is described. The method utilizes the differential ability of these two genera to ferment glucose. Acidification produced by the bacterial metabolism is demonstrated by the color change of an indicator (bromthymol blue) from blue-green to bright yellow. Where bacteria are inhibited by a sufficient concentration of the antibacterial drug tested, no color change occurs. The accurate quantitative results obtained with this method facilitate proper therapy for diseased fish, shrimps and oysters. The same method can in principle be applied to any other glucose-fermenting bacteria, when challenged with non-acidic antibacterial agents. 相似文献
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Abstract – Diet composition of Pterodoras granulosus was investigated from June 2004 to June 2005 in the Upper Paraná River floodplain, following invasion by two mollusc species Corbicula fluminea and Limnoperna fortunei . Stomach and intestinal contents analysis showed spatial differences in the diet composition. In the Baía River, P. granulosus diet consisted mainly of C. fluminea , whereas plant items dominated in the Ivinheima River, and L. fortunei was the most important food in the Paraná River. There was little selectivity in shell length consumed. In spite of C. fluminea being a larger mollusc, L. fortunei appears to be energetically more profitable because its shell is more fragile and is rapidly opened and digested. A considerable amount of closed shells of C. fluminea at the end of the digestive tract points to a possible role of P. granulosus as a mollusc disperser. 相似文献
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低盐胁迫对银鲳幼鱼肠道消化酶活力的影响 总被引：3，自引：2，他引：1
通过逐级降低水体盐度的方法,将银鲳幼鱼分别在盐度25、20、15和10的条件下饲养至120 h,检测不同盐度下、不同时间点银鲳幼鱼肠道脂肪酶、淀粉酶、胰蛋白酶和胃蛋白酶的活力。结果表明,随着盐度的降低和处理时间的延长,脂肪酶的活力总体表现出先升后降的变化趋势(P0.05);淀粉酶的活力呈升高的变化趋势(P0.05);胰蛋白酶和胃蛋白酶活力的变化趋势不同,胰蛋白酶的活力呈现升高的趋势(P0.05),而胃蛋白酶活力呈下降的变化趋势(P0.05)。说明盐度降低会对银鲳幼鱼肠道的消化酶产生激活作用,从而促进肠道对营养物质的利用,达到补充机体所损失的能量的目的。但对于不同种酶,激活的顺序和程度却不尽相同,甚至当超出一定的耐受范围后,酶活力反而被抑制。在本研究中,随着盐度的下降和处理时间的延长,脂类物质首先被大量消耗,然后是淀粉类物质,而蛋白类物质在整个过程中的利用率较低。因此建议,在雨季来临之前,提高脂类和淀粉类物质的投喂量,将有助于提高幼体对低盐度的耐受性及其成活率。 相似文献
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