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51.
为探讨接种贝莱斯芽孢杆菌SW5菌株对发酵鳀鱼鱼露的影响,以贝莱斯芽孢杆菌SW5为唯一发酵菌株,以低值鳀鱼为原料,测定鱼露发酵过程中氨基酸态氮(AA-N)、挥发性盐基氮(TVB-N)、pH值、总酸含量,并使用顶空固相微萃取结合气相色谱-质谱联用仪(HS-SPME-GC-MS)测定发酵结束后发酵液的挥发性风味物质。结果表明,在发酵期间,利用SW5菌株发酵的处理组1在发酵第6天时AA-N含量最高,为0.76 g·100 mL-1,达到市售二级鱼露标准。3种处理组和舟山商品鱼露中共检测出挥发性风味成分82种,主要是醇、酸、醛、酮、呋喃、烷烃及其他类化合物,接种组中的挥发性风味物质(40种)较未接种组(35种)有所增加。综上,接种贝莱斯芽孢杆菌SW5菌株发酵鱼露,能缩短发酵时间,增加风味物质种类,该菌株可用作海洋蛋白质源发酵精深加工的优良微生物菌株。 相似文献
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为实现掺杂掺假鸡肉的快速、客观评价,该研究利用电子鼻和电子舌联合检测技术对掺杂鸡肉糜进行快速检测,通过对采集的数据进行主成分分析和偏最小二乘法分析,所得结果表明,采用主成分分析,电子鼻和电子舌联合检测掺大豆蛋白鸡肉糜和掺淀粉鸡肉糜的主成分总贡献率分别为99.8%和99.1%;采用偏最小二乘法分析,电子鼻和电子舌联合检测鸡肉糜中掺杂大豆蛋白含量的预测值与真实值之间的决定系数为0.992,均方根误差为2.8%;联合检测鸡肉糜中掺杂淀粉含量的预测值与真实值之间的决定系数为0.996,均方根误差为2.4%。表明电子鼻和电子舌联合检测对鸡肉糜的掺杂情况具有良好的区分和预测能力,并且是一种有效、高精度的肉类掺假检测方法。 相似文献
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In the Coral Triangle community-based marine protected areas (MPAs) are being established at a prolific rate. Their establishment can benefit both fisheries and biodiversity, and they provide both a socially and economically acceptable means of managing coral reefs in developing nations. However, because such MPAs are typically small (usually <0.5 km2), they will rarely provide protection to large mobile fishes. An exception to this limitation may exist when community-based MPAs are established to protect small sites where vital processes occur, such as fish spawning aggregations (FSAs). To test the effectiveness of small (0.1–0.2 km2) MPAs for protecting FSAs, we monitored three FSA sites where brown-marbled grouper (Epinephelus fuscoguttatus), camouflage grouper (Epinephelus polyphekadion) and squaretail coralgrouper (Plectropomus areolatus) aggregate to spawn. Sites were monitored during peak reproductive periods (several days prior to each new moon) between January 2005 and November 2009. All three sites are located in New Ireland Province, Papua New Guinea, and had been exploited for decades, but in 2004 two sites were protected by the establishment of community-based MPAs. The third site continued to be exploited. Over the monitoring period densities of E. fuscoguttatus and E. polyphekadion increased at both MPAs, but not at the site that remained open to fishing. At one MPA the densities of E. polyphekadion increased tenfold. Our findings demonstrate that community-based MPAs that are appropriately designed and adequately enforced can lead to the recovery of populations of vulnerable species that aggregate to spawn. 相似文献
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Constructed ponds are an important consideration in the conservation of wetland biota in agricultural landscapes. Twenty-two natural ponds and 22 adjacent constructed ponds (farm dams) were surveyed on the Southern Tablelands of New South Wales to compare patterns of use by frogs and develop frog conservation recommendations. Farm dams supported similar numbers of frog species to natural ponds, although differences in frog assemblage were observed between the pond types. Limnodynastes tasmaniensis and Uperolia laevigata were significantly more likely to occur at farm dams while L. peronii was more likely to occur at natural ponds. Results suggest waterbodies with high levels of emergent vegetation cover that lack fish are likely to support a high number of frog species, regardless of origin (i.e. natural or constructed). However, it is important for landholders to conserve natural waterbodies as these environments appear likely to support frog species that do not use farm dams. 相似文献
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Julien Cucherousset 《Biological conservation》2008,141(12):2984-2992
We studied the patterns of commonness and rarity for one vertebrate (fish) and four freshwater insect taxa (Ephemeroptera, Plecoptera, Trichoptera and Coleoptera) in southwestern France (57,000 km2), and we analysed the relationships between the location of sites and the contribution of commonness and rarity to species richness within a large stream system. Richness patterns in fish and aquatic insects were related to the location of sites within the stream system. The number of common and rare fish species increased from up- to downstream areas as a result of downstream additions of species. The number of common insect species peaked in the intermediate section of the river continuum, whereas rarity increased with decreasing elevation. In all taxa, common species gave a closer approximation to overall patterns of species richness than did rare ones. The biodiversity patterns of river animals emerged from convergence in the distributions of common and rare species (fish), or mostly from the distribution of common species (insects). However, in fish, Ephemeroptera and Plecoptera, the rarer species became almost equally, or more strongly correlated with overall species richness when increasing information along the common-to-rare and rare-to-common sequences. These patterns suggested that rarer species show a similar or stronger affinity, on a species-for-species basis, for high richness areas than do the commoner species. These schemes have implications for biodiversity assessments, as studies using common species richness to target important areas for monitoring or conservation efforts within stream systems will not necessarily identify areas important for rare species, and vice versa. 相似文献
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本研究通过对2010~2011年渤海大面调查所获得的渔获物进行胃含物分析,了解当前渤海鱼类的食物关系及其变化。结果显示,渤海生态系统的27种鱼类有12种低营养级鱼类、12种中营养级鱼类和3种高营养级鱼类,包括了杂食性鱼类、浮游动物食性鱼类、底栖动物食性鱼类、混合动物食性鱼类和鱼食性鱼类,各鱼种营养级较20世纪90年代变化不大。3种高营养级鱼类均为鱼食性鱼类,饵料生境宽度值均很低,属于狭食性鱼类;矛尾虾虎鱼(Chaeturichthys stigmatias)和小黄鱼(Pseudosciaena polyactis)是渤海饵料生境宽度最大的2种鱼,同时也是当前渤海生态系统食物网中最重要的饵料种类,其广食性有利于食物网各营养层次的物质、能量流动。当前渤海食物网中浮游食物链削弱,主要食物链转变为“植物、有机碎屑→鼓虾→鱼类”和“底栖动物→虾虎鱼、小黄鱼→大型经济鱼类”。 相似文献
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为了探究β-伴大豆球蛋白(7S)中α和α′亚基缺失对大豆分离蛋白乳化特性的影响,该文以东农47(对照)和3种不同蛋白亚基缺失型(α缺失、α′缺失以及α、α′缺失)大豆为原料提取大豆分离蛋白(SoyProteinIsolate,SPI),通过十二烷基磺酸钠聚丙烯酰胺凝胶电泳(Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis,SDS-PAGE)技术分析其亚基组成,然后制备乳状液并测定乳化活性指数(Emulsifying Activity Index,EAI)、ζ-电位、粒径、微观结构、稳定动力学指数(Turbiscan Stability Index,TSI)及界面蛋白吸附量。结果表明:α′亚基缺失型SPI乳状液乳化活性指数最大,为87.59 m2/g;ζ-电位绝对值最大,为47.7 mV;粒径最小,为2.223μm;显微结构显示其分子最小且分布最均匀,稳定动力学指数最小;界面蛋白吸附量最大,为31.40%。4种不同SPI乳状液的稳定性结果由大到小为α′亚基缺失型、东农47、α亚基缺失型、α和α′亚基缺失型。研究结果可为高乳化性大豆蛋白系列产品的开发应用提供理论支撑和技术支持。 相似文献
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