A novel combined recirculating treatment system for intensive marine aquaculture

This study established a pilot‐scale recirculating treatment system that coupled an ecological process with a biological process to achieve adequate water quality and to minimize the water consumption for intensive marine culture. The recirculating treatment system consisted of a settling cell, a biofilter tank, a bivalve tank and gravel beds. The toxic pollutants, threatening the growth of bivalves, were reduced by the settling cell and the biofilter tank, so that the polyculture of shrimp and bivalves could be achieved. The living bivalve tank could function well as a remover of remaining small suspended solids (SS), and other pollutants. As the SS was reduced to a very low level by bivalve tank before the water flowing into the gravel beds, the risk of clogging was prevented. The studies suggested that the system maintained high removal efficiencies of SS, ammonium nitrogen () and nitrite nitrogen () and could contribute to the increase in shrimp yield.     

A Novel C1q Domain-Containing Protein Isolated from the Mollusk Modiolus kurilensis Recognizing Glycans Enriched with Acidic Galactans and Mannans

C1q domain-containing (C1qDC) proteins are a group of biopolymers involved in immune response as pattern recognition receptors (PRRs) in a lectin-like manner. A new protein MkC1qDC from the hemolymph plasma of Modiolus kurilensis bivalve mollusk widespread in the Northwest Pacific was purified. The isolation procedure included ammonium sulfate precipitation followed by affinity chromatography on pectin-Sepharose. The full-length MkC1qDC sequence was assembled using de novo mass-spectrometry peptide sequencing complemented with N-terminal Edman’s degradation, and included 176 amino acid residues with molecular mass of 19 kDa displaying high homology to bivalve C1qDC proteins. MkC1qDC demonstrated antibacterial properties against Gram-negative and Gram-positive strains. MkC1qDC binds to a number of saccharides in Ca²⁺-dependent manner which characterized by structural meta-similarity in acidic group enrichment of galactose and mannose derivatives incorporated in diversified molecular species of glycans. Alginate, κ-carrageenan, fucoidan, and pectin were found to be highly effective inhibitors of MkC1qDC activity. Yeast mannan, lipopolysaccharide (LPS), peptidoglycan (PGN) and mucin showed an inhibitory effect at concentrations three orders of magnitude greater than for the most effective saccharides. MkC1qDC localized to the mussel hemal system and interstitial compartment. Intriguingly, MkC1qDC was found to suppress proliferation of human adenocarcinoma HeLa cells in a dose-dependent manner, indicating to the biomedical potential of MkC1qDC protein.     

Analysis of Phytosterol,Fatty Acid,and Carotenoid Composition of 19 Microalgae and 6 Bivalve Species

ABSTRACT

In this study, the functional components of 19 microalgae and 6 bivalve species were investigated in the context of the application in bivalve feeding and human health food. Principal component analysis was performed to detect any association between the functional components and individual microalgal species or taxonomic group. The proportions of the functional components differed depending on the taxonomic group or species of microalga. The genera Cheatoceros, Thalassiosira, and Isochrysis contained high concentrations of fucosterol and fucoxanthin, which are present in large amounts in brown algae. Diatoms, haptophytes, and eustigmatophytes, which are used as feed for bivalves, were rich in fucosterol and eicosapentenoic acid (EPA); further, haptophytes were rich in docosahexaenoic acid (DHA). In addition, the microalgae associated with red tide, i.e., the raphidophytes, were found to be rich in fucoxanthin, β-sitosterol, and EPA, whereas dinoflagellates were rich in DHA. Seven bivalve species also contained high concentrations of fucosterol, EPA, and DHA, as did microalgae, which were used to feed by bivalves. These results are useful in selecting microalgae effectively as feed of the bivalves.     

海洋经济软体动物肌肉副肌球蛋白分布特性初探

以肌肉组织的蛋白为切入点,探索海洋经济软体类主要可食部位的化学特性与差异,并对软体类副肌球蛋白的分布特点进行初步探索。研究对象为商品活体经济软体类,包括菲律宾蛤仔、毛蚶、脉红螺、皱纹盘鲍及长蛸5个种类。首先,对可食部位化学组成及氨基酸组成进行分析比较,结果显示,5种软体动物间一般化学组成差别不大,肌肉中均含有17种氨基酸,且亮氨酸和赖氨酸含量均较高,氨基酸含量无显著差异。然后,对肌肉组织蛋白组分及各组分含量分布进行分析与比较,SDS-PAGE分析表明,5种软体动物肌肉中均含有肌球蛋白、肌动球蛋白、副肌球蛋白及原肌球蛋白等重要组分;同时在菲律宾蛤仔、毛蚶及皱纹盘鲍的肌肉中含有分子量高于200 ku的未知蛋白聚合物。基于质谱分析鉴定并结合分子量进一步计算,确定该蛋白聚合物为副肌球蛋白聚合体。综上可知,不同软体类肌肉蛋白组分分布的差异主要体现在副肌球蛋白,因此,副肌球蛋白及其聚合体的分布特性值得进一步探索。     

贵阳市花溪河软体动物资源调查

为了解软体动物的群落特征,探究它们在河流中的生态功能,对花溪河软体动物的资源状况进行了调查.结果表明:花溪河软体动物有26种,隶属13科21属,其中,以紧缢小田螺[Paludinella stricta (Gould)]、赤豆螺[Bithynia fuchsiana (Moellendorff)]、梨形环棱螺[Bellamya purificata (Heude)]、平盘螺[Valvata cristata(Muller)]和光钉螺[Katayama nosophora (Robson)]为优势种.软体动物资源丰富.     

软体动物毛蚶RNA干扰技术的应用研究

为了在软体动物中建立RNA干扰技术,以用于毛蚶基因功能研究。通过体外转录技术合成双链RNA,并将其注射毛蚶干扰目标基因的表达。肌肉注射双链RNA 48 h后取样,用RT-PCR技术检测目标基因的表达变化,以确定干扰的有效性。结果显示：各目标基因的表达均能被各自特异的双链RNA有效干扰而降低。在注射双链RNA后不同时间点,即12、48、72、96、120 h,取样检测目标基因的时序表达,以确定目标基因表达被干扰的时间效应。发现目标基因的表达在48 h即能有效降低,而且有效时间能持续至120 h以上。对注射双链RNA的动物个体,于48 h取样检测不同组织的目标基因表达,发现毛蚶的RNA干扰效应能系统性地在不同组织发生,表明干扰效应能在不同组织之间进行传递。因此,本研究报道了一种稳定的毛蚶RNA干扰技术,为在毛蚶中进行基因功能鉴定和抗病毒研究提供了一个有效的分子生物学的方法。     

滇西北四大高原湖泊软体动物现状调查

2008-2010年对滇西北洱海、程海、泸沽湖和碧塔海的软体动物现状进行了全面系统的调查,并在此基础上对比讨论4个湖泊间软体动物生物多样性的差异和水体富营养化过程中软体动物种群结构的改变.在泸沽湖采集到的软体动物标本种类最多,共计23种、1亚种;其次为洱海采集到14种,碧塔海和程海分别采集到6种和5种.将洱海记录的软体动物种类与此次采集到的种类对比,洱海的软体动物种群结构由底栖型向漂浮型转变,这可能与水体富营养化有关.     

滤食性双壳贝类对工厂化养殖废水中悬浮物的生物滤除研究

针对海水鱼类半滑舌鳎养殖池排出水中大量絮状悬浮物难以用常规机械过滤法去除的问题,选择适应能力强的滤食性双壳贝类长牡蛎(Crassostrea gigas)和紫贻贝(Mytilus galloprovincialis),通过现场实验测定了它们对鱼类养殖排出水中悬浮物的生物滤除能力。结果表明,在海水流速为100L·h-1条件下,牡蛎[壳高(9.80±0.45)cm,湿重(117.0±10.0)g]和贻贝[壳高(6.54±0.26)cm,湿重(29.7±2.4)g]对养殖排出水悬浮物的生物沉积速率分别为40.28～45.30mg·ind-1·d-1[平均(43.40±2.16)mg·ind-1·d-1]和6.96～8.87mg·ind-·1d-1[平均(7.66±0.99)mg·ind-·1d-1];在实验海水流速为150L·h-1条件下,牡蛎[壳高(9.33±0.99)cm,湿重(95.8±31.4)g]和贻贝[壳高(6.39±0.91)cm,湿重(28.0±15.4)g]对悬浮物的生物沉积速率分别为13.68～22.50mg·ind-1·d-1[平均(17.35±4.59)mg·ind-1·d-1]和5.37～...     

麒麟菜与贝类混养体系净化富营养化海水的研究

研究了热带亚热带类型双壳贝类沟纹巴非蛤(Paphia exarata Philippi) 和热带大型海藻异枝麒麟菜 (Kappaphycus striatum Schmitz) 净化富营养化海水的效果。发现沟纹巴非蛤和麒麟菜混养能有效地清除富营养化水体中的N、P和chla。影响综合评价指标、N清除率、P清除率和chla清除率的因素均为麒麟菜﹥贝;其中麒麟菜对各指标的影响均为极显著(P﹤0.01);贝对N清除率、chla清除率的影响为极显著(P﹤0.01),对综合评价指标、P清除率有一定影响,但不显著。最佳混养组合为：麒麟菜养殖量6Kg/m3、沟纹巴非蛤养殖量60只/m3（40g±2g/只）。