Screening and Characterization of Nitrite-Degrading Bacterial Isolates Using a Novel Culture Medium     

MA Qingshan  HE Zengguo 《中国海洋大学学报(英文版)》2020,19(1):241-248

In this study,a novel culture medium that simulates shrimp pond conditions was established to screen nitrite-degrading isolates.The medium was supplemented with nitrite as a nitrogen source and shrimp feed as the major carbon source,to achieve the high nitrogen and low carbon nutritional status found in shrimp farming ponds.Screening using this medium identified potent denitrifying Bacillus isolates,among which Bacillus subtilis M7-1 was considered best.M7-1 was able to completely degrade nitrite-N in 24 h without much consumption of dissolved oxygen.Efficient denitrification activity took place in liquid cultures within a set of non-stringent ranges of pH(5.0–9.0),salinity(0–30)and temperature(25–35℃).The denitrifying enzyme gene was amplified,sequenced and further identified as nirS type.In biosecurity assessments,M7-1 had no negative effects on shrimps at a dose of 106 cfu mL−1.M7-1 could therefore be used in aquaculture to reduce and control the nitrogen concentration,and to promote the development of sustainable and healthy culture systems.  相似文献   

水体中芽孢杆菌和微囊藻的生长及其资源竞争     

瞿建宏  刘韶斌 《广东海洋大学学报》2002,22(3):13-18

以C、N、P为主要限制性因子研究了芽孢杆菌和微囊藻在水中的生长率 ,并据Monod方程了解种群增长率与营养浓度之间的关系 ,以判断藻菌资源竞争的结果。研究结果显示 ,氮浓度的升高或磷浓度的降低 ,即N/P比值的升高 ,有利于芽孢杆菌的生长 ;而当氮浓度一定时 ,C/N比值越高 ,芽孢杆菌生长得越好。而微囊藻作为一种自养的光合植物 ,其生长与水中的C源无关 ,与氮磷浓度有关。氮磷浓度越高则生长越好。在此研究结果基础上进行藻菌生长动态的比较表明 ,在氮限制条件下 ,微囊藻的生长率稍高于芽孢杆菌 ;在磷限制条件下 ,芽孢杆菌的生长率总是大大高于微囊藻的生长率  相似文献   

A geomicrobiological study of soils collected from auriferous areas of Argentina     

Alain Melchior  Léon Dejonghe  Guillermo Hughes 《Journal of Geochemical Exploration》1996,56(3):219-227

Geomicrobial and geochemical studies were carried out in Argentina (Patagonia, Chubut Province) on four Au and polymetallic sulfide vein-type deposits. A horizon soils were analyzed for Bacillus reacting to lecithin [Bacillus L.(+)], Au and 12 additional elements. In two of the four sampling sites, exhibiting known and relatively simple mineralized structures, Bacillus L.(+) populations are clearly related to Au, As, Pb, Zn, Cu-sulfide mineralization. In areas containing more complex mineralized structures, the spatial relationship between Bacillus L.(+) and metals in the A horizon is more difficult to interpret. Results of a factor analysis performed on all analytical data (n = 130) suggest a partial relationship between Bacillus L.(+) and Au-As-Y pedochemical associations located above known Au mineralization. Bacillus L.(+) was first analyzed in Argentina in December 1994 and re-analyzed in Belgium five to seven months later. Most of the Bacillus contents (85%) of the Belgian tests are higher than those determined in Argentina. The present results and data of a previous study in Mexico (Melchior et al., 1994a; Melchior et al., 1994b) suggest that this may be the result of temperature variations during sample storage between periods of microbial analysis. From a strictly analytical point of view, the geomicrobial method is not an accurate, reproducible technique. However, Bacillus L.(+) can be used as a microbiological indicator of Au and polymetallic mineralization at a reconnaissance-level regional survey. At a local scale, this microbiological tool should be combined with classical exploration techniques such as soil geochemistry. It is recommended that the collection of all A horizon samples (for microbial study) should be accompanied by B or C horizon soils (for potential geochemical study, after prioritizing targets) so that a second field sampling program does not have to be undertaken.  相似文献   

Study on the flocculability of metal ions by<Emphasis Type="Italic">Bacillus mucilaginosus</Emphasis> GY03 strain   总被引：1，自引：0，他引：1  

连宾陈烨  袁生朱立军  刘丛强 《中国地球化学学报》2004,23(4):380-386

This study deals with the flocculability of two types of metal ions by Bacillus macilaginosus GY03 Strain, with an emphasis on the influence of pH conditions, volume and time of flocculants produced by GY03 Strain on the adsorption of metal irons such as Pb^2 and Mn^2 and the capabilities of floceulants to adsorb metal ions of different concentrations. The results showed that microbial flocculants produced by Bacillus mucilaginosus GY03 Strain are highly capable of flocculating metal ions, but show different effectiveness with respect to the adsorption of Pb^2 and Mn^2 . In accordance with the experimental data and actual waste-water treatment conditions, the relevant regression equation of floeculation has been deduced, which has found some application in practice. The experimental results of this study demonstrated that microbial flocculants produced by Bacillus mucilaginosus can be used to treat metallic ion-containing waste water. In practical application the volume of microbial floceulants required and flocculation conditions should be taken into comprehensive consideration in accordance with the properties of metal ions, the composition of anions and the solubility of other metals, in combination with the cost and effectiveness of floceulants to be used. Floeeulant used in this experiment has the advantages of being applied over a wide range of pH values, small flocculant volume, and rapid speed of floeeulation. So this kind of flocculant is within excellent prospect of application.  相似文献   

Study on the Flocculability of Metal Ions by Bacillus Mucilaginosus GY03 Strain   总被引：13，自引：0，他引：13  

连宾  陈烨  袁生  朱立军  刘丛强 《中国地球化学学报》2004,23(4)

Inrecentyears,withtherapiddevelopmentofindustrialeconomy ,wastewaterisdischargedinhugevolumeandtheaccumulationofheavymetalionsinsoilsandwatersourcesisspeededuprapidly .Asaresult,waterpollutionhasbecomeadailydeterioratingproblem .Heavymetalsareeasytoenterthefoodchain ,therebyconstitutingagreatthreattothehealthofanimalsandhu manbeings .Therefore,howtoeffectivelyhandleheavymetalpollutionhasbecomeacommonat tractionformankind .Theroutineheavymetaltreatmentmethodsaremainlythechemical,phys icalandphy…  相似文献   

抑制黄曲霉毒素的深海环状芽胞杆菌发酵条件优化          下载免费PDF全文

徐静静  闫培生 《应用海洋学学报》2022,41(4):693-700

环状芽胞杆菌(Bacillus circulans)菌株FA13在M2培养基中的发酵无细胞上清液对寄生曲霉(Aspergillus parasiticus)突变菌株NFRI-95菌丝生长和黄曲霉毒素的产生表现出明显的抑制作用。为了最大限度地提高活性物质的产量,本研究对从南大西洋深海沉积物中分离到的环状芽胞杆菌菌株FA13的发酵条件进行了均匀设计发酵优化。优化后,菌株FA13的发酵液10倍稀释液对寄生曲霉突变菌株NFRI-95的菌丝生长抑制率从10.98%提高到70.57%,黄曲霉毒素产生抑制率从41.43%提高到100.00%;对应的发酵条件为发酵温度38.70 ℃,接种量6.00%,海水体积占比0.00%,培养基pH 8.71,培养时间6 d。  相似文献   

虾夷马粪海胆黑嘴病的初步研究   总被引：6，自引：1，他引：5  

李太武  徐善良  王仁波  许淑芬  苏秀榕 《海洋科学》2000,24(3):41-44

对虾夷马粪海胆“黑嘴病”进行了初步的研究。经分离、纯化后鉴定黑嘴病的病原菌为坚强芽孢杆菌 (BacillusfirmusBredemannetWarner)。同时报道了该菌为革兰氏阳性杆菌 ,大小为(0.6～0.7)μm×(0.8～1.0)μm。可在1%～7%NaCl中生长 ,最适盐度2～3 ;最适pH为7～8;生长温度为8～26℃ ,最适生长温度为15℃。该菌对磺胺甲基异恶唑、复方新诺明和头孢噻肟等抗生素敏感 ,可用之治疗  相似文献   

Biosorption of Procion Red MX 5B by Bacillus subtilis and Its Extracellular Polysaccharide: Effect of Immobilization     

Arthur Raj Binupriya  Muthuswamy Sathishkumar  Chang Sub Ku  Sool Il Yun 《洁净——土壤、空气、水》2010,38(8):775-780

Bacillus subtilis and its extracellular polysaccharide (EPS) were used in free form as well as immobilized form as biosorbent for the removal of an anionic dye Procion Red MX 5B. Low pH was favourable for biosorption. Immobilization resulted in reduced biosorption of the dye. The presence of functional groups responsible for the high adsorption capacity in free cells (FC) and EPS was confirmed by FTIR analysis. High Q_max and b values were noted in the case of FC and free EPS in contrast to immobilized cells and EPS. The kinetics data showed that the adsorption system followed pseudo‐first‐order reaction at low dye concentration. Desorption of the dye was found to be 100% in 1 N NaOH. In the case of immobilized biomass and EPS the alginate was found to be unstable under high alkaline conditions of NaOH.  相似文献   

Influence of Culture Conditions on Poly‐3‐Hydroxybutyrate Production by a Newly Isolated Bacillus cereus Y23     

Oxana Yashchuk  lida B Hermida 《洁净——土壤、空气、水》2020,48(5-6)

Polyhydroxyalkanoates (PHAs), environmental friendly polyesters, can be produced by a wide range of microorganisms in nutrient‐limiting conditions. In the present study a new bacterial strain, able to produce high quantities of poly‐3‐hydroxybutyrate (PHB), is isolated from contaminated soil. The isolate is characterized and identified as Bacillus cereus Y23, based on morphological, physiological characteristics, and 16S ribosomal RNA gene sequences. PHB production is evaluated using different carbon and nitrogen sources and nutritional and culture conditions are optimized. The highest PHB production of 5.12 g L^?1 was obtained in growth medium containing fructose and ammonium sulfate at a C/N ratio of 30, 0.3% yeast extract, 4.5 g L^?1 phosphate solution, pH 7, inoculum size of 0.3%, and agitation rate of 150 rpm after 48 h of incubation at 32 °C. The PHB production decrement can be attributed to the intracellular utilization of the polymer during the stationary phase of the cellular growth and to the sporulation process. The presence of the main functional groups of PHB polymer is verified by Fourier‐transform infrared analysis. At optimum conditions, B. cereus Y23 turned out to be a good candidate for industrial production of PHB since it accumulates up to 67.9% of its dry weight.  相似文献   

解淀粉芽孢杆菌化感作用对球等鞭金藻生长抑制效果     

李晓英  陈义华  赵裕超  冯森磊  李雯倩  朱强  董志国 《海洋科学》2021,45(1):62-69

为探明解淀粉芽孢杆菌及其代谢物对海水养殖环境中微藻的化感作用,本文以实验生态学方法研究了解淀粉芽孢杆菌对球等鞭金藻生长的生态作用。实验设计了不同剂量(100mL、500mL、1000mL)的解淀粉芽孢杆菌纯菌液、解淀粉芽孢杆菌代谢产物、解淀粉芽孢杆菌及代谢产物混合液三种组合研究其对球等鞭金藻的培养影响。结果显示,添加纯菌液组金藻在第1~2 d增长缓慢,藻细胞数无显著差异,但均低于对照组,其中第3~4 d显著低于对照组(P<0.05);添加菌代谢产物组第1 d金藻细胞数与对照组相比无显著差异,2~4 d显著低于对照组(P<0.05);添加菌液及代谢产物混合液组中100mL组金藻生长较缓慢,500μL和1000μL组藻细胞数呈下降趋势,藻细胞数显著低于对照组(P<0.05),1000μL组金藻第2 d已全部死亡。各剂量组藻细胞数均呈现解淀粉芽孢杆纯菌液、解淀粉芽孢杆菌代谢产物、解淀粉芽孢杆菌及代谢产物混合液依次下降,另外,除菌代谢物1000μL剂量组藻细胞数大于500μL剂量组外,其余各组添加量越大藻细胞数越少,呈现剂量效应关系。解淀粉芽孢杆纯菌液、解淀粉芽孢杆菌代谢产物、解淀粉芽孢杆菌及代谢产物混合液抑制率最高分别为35.84%、69.75%、100%,表明解淀粉芽孢杆菌对球等鞭金藻的作用为化感抑制,且抑制效果具有剂量效应。本研究为解淀粉芽孢杆菌在水产养殖中应用效果评价提供了科学依据,同时为赤潮藻类治理提供新思路。  相似文献