利用复合微生物降解养殖水体中亚硝酸盐的初步研究

在养殖水体中对保存的芽孢杆菌、反硝化细菌、乳酸菌降解亚硝酸盐的能力进行比较,发现3种菌株对亚硝酸盐均能较好地降解,但降解速度不同,反硝化细菌>乳酸菌>芽孢杆菌;对3种菌株混合接种发现,具有较好净化水质效果的最佳接菌配比为芽孢杆菌∶反硝化细菌∶乳酸菌=1∶1∶2,在30℃、接种量为1%的条件下,以该配比接种亚硝酸盐,硝酸盐初始质量浓度分别为12.85、54.42mg/L的模拟养殖水体中,其亚硝酸盐、硝酸盐降解率在24h内均超99.99%,水体中的pH值显著降低,水体中的氨氮变化较小,可以实现对养殖水体的快速脱氮。     

三种微生物制剂对有机物废水中氨氮及亚硝酸盐的影响

实验采用复合净水菌、复合芽孢杆菌、光合细菌与空白对照比较了三种微生物制剂对有机物废水中氨氮及亚硝酸盐的处理效果。结果显示：清除氨氮方面：利用微生态制剂微生物制剂净化7d,三种微生物制剂对有机物污染水体中氨氮的清除率均极显著大于对照组（P〈0.01）,处理组之间复合芽孢杆菌的氨氮降解率56.58%,显著大于降解率分别为42.64%和44.02%的复合净水菌和光合细菌组（0.01〈P〈0.05）。清除亚硝酸盐方面：三种微生物制剂对亚硝酸的降解率均极显著大于对照组（P〈0.01）,而复合芽孢杆菌对亚硝酸的降解率68.84%,显著大于复合净水菌47.70%及光合细菌组37.17%（0.01〈P〈0.05）。结果表明：三种微生物制剂对有机物污染的水体中的氨氮及亚硝酸盐均具有降解效果,其中复合芽孢杆菌对于降低水体中氨氮和亚硝酸盐效果最佳。     

养虾如何选用菌制剂

养虾用的菌制剂首选芽孢杆菌,其次是光合细菌以及乳酸菌产品。芽孢杆菌一般产品为枯草芽孢杆菌、地衣芽孢杆菌、纳豆芽孢杆菌、腊状芽孢杆菌,是所知极少数可以分解大分子有机质如残饵粪便的菌种。     

养殖水体中高效氨氮降解菌的分离与鉴定

以(NH4)2SO4为惟一氮源的选择性培养基,从养鱼池水中分离筛选到1株高效氨氮降解菌X2。当NH4 -N初始质量浓度为50 mg/L时,该菌株在24 h内的氨氮降解率>95%,并具有硝酸还原和亚硝酸还原能力。初步鉴定该菌株为巨大芽孢杆菌(Bacillus megaterium)。     

“精博活菌王”使用实例

2008年公司成功推出了采用新一代的进口有益微生物菌种发酵而成的复合微生物制剂-“精博活菌王”,除传统的乳酸菌、光合细菌、酵坶菌、放线菌、硝化细菌与反硝化细茼外,添加了水产专用的净水芽孢杆菌,主要用途：水体降亚硝酸盐、降氦氮、除臭、净水。     

微生物制剂对水体中亚硝酸盐降解的研究

枯草芽孢杆菌是一类需氧非致病菌,能快速分解水体中的残饵及粪便等有机物,也可以促进硝酸盐或亚硝酸盐的氧化作用,从而净化水质。硝化细菌能吸收利用水中高浓度的亚硝酸盐,将其转化为硝酸盐等无害物质。我们将具有较强的亚硝酸盐降解能力的枯草芽孢杆菌和硝化细菌经发酵培养后制备成一种用于降解亚硝酸盐的微生物复合制剂－亚硝消。本文具体介绍在高邮张轩、三垛的罗氏沼虾养殖池塘及四大家鱼养殖中进行试验的过程和结果。     

微生态制剂及其在水产养殖中的应用问题(三)

五、微生态制剂在水产养殖中的应用目前,我国在水产养殖过程中使用微生物活菌制剂品种和生产厂家多,产品功能各异,养殖业者对其效果也难以作出准确的判断。市售的微生物活菌制剂大概可分下面几大类:从微生物种属上分类,有光合细菌、芽孢杆菌属、硝化细     

光合细菌Ⅰ的分离及其对水体中亚硝酸盐降解的研究

从对虾养殖池的底泥中分离和筛选出光合细菌Ⅰ,优化其培养条件后,用于降解养殖污水中亚硝酸盐。试验得出该菌最佳培养条件:pH为7.5,碳源为乙酸钠,碳源浓度2‰,接种量6%,25～30℃,3000lx条件下培养5d;该菌对亚硝酸盐的去除率为70.4%。     

如何对养殖水体氨氮和亚硝酸盐实施大清扫

氨氮和亚硝酸盐是养殖水体最常见隐形杀手.随着养殖密度的不断增大,经常伴随在养殖的全过程,给养殖动物造成诸多不良后果.1 产生过程氨氮和亚硝酸盐是由养殖动物的排泄物、水体施肥、动植物尸体、淤泥中的有机质等厌氧分解转化而来.亚硝酸盐是氨氮在亚硝化细菌和反硝化细菌的参与下转化而成,一旦水体溶氧不足,硝化细菌及反硝化细菌数量不足等,正常的硝化作用受阻,亚硝酸盐的生产机制就会加强,并在水体内大量积累,形成潜在危害.可以说,水体中的含氮物质是生产亚硝酸盐的原料,而亚硝化细菌和反硝化细菌则是加工厂,水体缺氧或微缺氧是产生的环境条件.     

３种微生态制剂对养殖水体水质影响的比较研究

对3种微生态制剂改善河蟹养殖池水质的效果进行分析比较。实验组各池中分别加入超浓缩光合细菌(PSB)、"西菲利"活菌生物净水剂、活菌净水剂以及3种微生态制剂组成的混合制剂。观察氨态氮、亚硝态氮、硫化氢、溶解氧、化学耗氧量、pH及异养菌总数等水质指标。结果表明:3种微生态制剂均能改善水质,抑制异养菌的过度增长,但对水质指标的改善各有侧重,混合制剂优于单一制剂。     

氨氮和亚硝酸氮快速准确测定方法研究

本研究提出了用液体标准色阶快速准确测定氨氮和亚硝酸氮的比色方法。研究的液体标准色阶的稳定时间在一年以上，氨氮和亚硝酸氮的测定误差分别为0．2mg／L和0．02mg／L。用本方法对名种类型的水样进行测定，结果表明，本方法与传统的分光光度法测定结果一致，适于海淡水养殖单位的现场使用。     

Use of probiotics Bacillus coagulans,Rhodopseudomonas palustris and Lactobacillus acidophilus as growth promoters in grass carp (Ctenopharyngodon idella) fingerlings

The present research evaluated the effects of three probiotics on the growth performance and intestinal digestive enzyme activity in fingerlings of grass carp, Ctenopharyngodon idella. Three treatments (T‐1, T‐2 and T‐3) were fed with diets containing different viable bacteria with a final concentration 10⁶ CFU g^?1 feed (Bacillus coagulans, Rhodopseudomonas palustris and Lactobacillus acidophilus, respectively) and the control was fed with basal diet without probiotics. All the diets supplemented with probiotics resulted in better (P < 0.05) final weight, daily weight gain and relative gain rate than control but no significant differences were observed among the treatment groups. The highest protease activity was observed in T‐1. However, T‐2 and T‐3 showed no difference (P > 0.05) in protease and cellulase activities compared with the control. The protease activity was higher in the foreintestine than in the hindintestine (P < 0.05), and the reverse was observed in cellulase activity. As for amylase activity, there was no difference between foreintestine and hindintestine. In conclusion, the three selected probiotics increased the growth performance of grass carp fingerlings. Furthermore, different digestive enzyme activity was observed in different intestine segment.     

亚硝态氮对中华鳑鲏的急性毒性及短期影响

静水试验条件下研究了亚硝态氮对体质量(0.636±0.09) g的中华鳑鲏急性毒性及短期胁迫下对其体内两种酶活性的影响。在水温25℃、溶解氧6.3 mg/L、pH 7.4时,测定亚硝态氮对中华鳑鲏的24 h半致死质量浓度,并设置高、中、低3个亚硝态氮质量浓度组[1.28、0.64、0.43 mg/L(1/10×24 h半致死质量浓度、1/20×24 h半致死质量浓度、1/30×24 h半致死质量浓度)],于0、24、48、72 h采集血样,测定血清中过氧化氢酶和碱性磷酸酶的活性。试验结果表明,亚硝态氮对中华鳑鲏的24 h半致死质量浓度为12.76 mg/L。在亚硝态氮胁迫作用下,中华鳑鲏血清中过氧化氢酶活性先显著上升,48 h后开始下降;碱性磷酸酶活性变化则是先显著下降,在48 h恢复,然后再下降。碱性磷酸酶活性在24 h和72 h均受到明显抑制。亚硝态氮质量浓度和暴露时间两者之间存在显著交互作用,碱性磷酸酶可以作为亚硝态氮毒性检测的生物标记物。     

Bacterial communities and predicted nitrogen metabolism of heterotrophic‐ and probiotic‐based biofilms used for super‐intensive indoor shrimp culture

Biofilm‐based aquaculture systems constitute a promising alternative for intensive shrimp rearing. Microorganisms forming biofilms can recycle the nitrogen compounds the production units improving the water quality while using zero or limited water exchange. This study aimed to compare the taxonomic profiles and the predicted functions related to the transformation of nitrogenous compounds between a heterotrophic‐ (HtB) and a probiotic biofilm (PrB), and the effect of these on the water quality and the productive response of cultured shrimp. Libraries of the 16S‐rRNA gene (V3‐V4 region) were prepared and sequenced to be used as a taxonomic biomarker. Analysis of metagenomic datasets revelated that genera Halomonas, Planctomycetes and Rhodopirellula were the most abundant genera in HtB; meanwhile, Bacillus, Halobacillus and Flavobacterium dominated in PrB. Regarding nitrogen metabolism, the proportion of genes encoding enzymes catalyzing the six pathways shaping the nitrogen metabolism showed differences between biofilms, which could also explain the difference in water quality between treatments. Concerning the productive response of shrimp, no significant differences were detected except for survival, which was higher in PrB. Finally, the results suggest that biofilms harbour functions for nitrogen metabolism, including dissimilatory nitrate reduction, assimilatory nitrate reduction, denitrification, nitrification, nitrogen fixation and anammox; however, the balance of these functional capabilities seems to be relevant to maintain water quality.