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1.
以天薯11号为指示品种,研究了短小芽孢杆菌(Bacillus pumilus)BPS48对马铃薯生长期间病害及产量的影响。结果表明,马铃薯用短小芽孢杆菌(Bacillus pumilus)BPS48可湿性粉剂300倍液灌根后,病毒病发病率较轻;折合产量最高,为14 200 kg/hm2,较空白对照增产2 250 kg/hm2,增产率18.8%。用芽孢杆菌可湿性粉剂45 g/L浓度下浸种30 min后,马铃薯折合产量为10 600 kg/hm2,较空白对照减产1 350 kg/hm2,减产率11.3%。  相似文献   

2.
贾蓉  曲东  乔莎莎 《农业环境保护》2013,(12):2395-2402
发酵型微生物是铁还原菌中的主要类群,但其发酵产氢过程对铁还原的作用尚不清楚,为此采用接种水稻土浸提液混合培养的方法对微生物分别利用葡萄糖、丙酮酸盐和乳酸盐为碳源时,Fe(Ⅲ)还原过程中脱氢酶活性变化、培养体系pH、氢气分压及铁还原特征进行分析,探讨了发酵微生物脱氢产氢过程与微生物Fe(Ⅲ)还原的内在关系。结果表明:2种水稻土浸提液中的微生物均能够以葡萄糖为优势碳源进行脱氢、产氢及还原氧化铁,Fe(OH),可以诱导脱氢酶的产生,利用葡萄糖时脱氢酶活性在厌氧培养的4-6d出现最大峰值,利用丙酮酸盐和乳酸盐时脱氢酶活性出现峰值的时间分别为培养的15d和21-22d,脱氢酶活性出现峰值的时间与最大铁还原速率Vmax显著负相关、与最大反应速率对应的时间zk存在显著正相关关系。脱氢产氢过程中产生的H+导致培养体系pH的变化是影响铁还原过程的主要原因,培养体系pH与体系氢气分压及Fe(Ⅱ)累积量呈极显著负相关。微生物利用不同碳源产氢时,利用葡萄糖的产氢能力最高,丙酮酸盐次之,乳酸盐最低。Fe(OH)3的加入增加了氢气的消耗量,培养体系氢气分压与Fe(Ⅱ)累积量存在极显著正相关关系。  相似文献   

3.
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   

4.
李贻珍  张卫兵  张忠明 《核农学报》2022,36(8):1629-1637
凝乳酶是生产干酪中极为关键的酶制剂。在凝乳酶作用过程中,添加适量的氯化钙可缩短凝乳时间,增加凝块硬度,减少生产成本,对干酪品质的影响至关重要。本研究利用从甘肃省天祝藏族自治县牦牛牧区土壤中筛选得到的一株高效产凝乳酶的地衣芽孢杆菌菌株D3.11,优化培养后得到凝乳酶,通过分析凝乳过程中相关指标的变化规律、观察比较凝块的微观结构,研究氯化钙添加量对该酶凝乳性能的影响。结果表明,当氯化钙添加量为0.014%~0.022%时,地衣芽孢杆菌D3.11凝乳酶体系的黏度值随凝乳时间的延长先增大后保持稳定;地衣芽孢杆菌D3.11凝乳酶体系和商品酶体系的浊度值均随Ca2+浓度的增大而显著增大(P<0.05);地衣芽孢杆菌D3.11凝乳酶体系的粒径主峰分布在136.9~246.7 μm范围内,且粒径值在氯化钙添加量为0.020%时最大;流变学特性分析结果表明,地衣芽孢杆菌D3.11凝乳酶体系达到储能模量G'峰值的时间随氯化钙添加量的增加而缩短;两种酶体系的持水力在氯化钙添加量为0.014%~0.022%范围内显著增大(P<0.05),乳清OD值在氯化钙添加量为0.016%~0.022%范围内变化均不显著(P>0.05);通过激光扫描共聚焦显微镜观察凝块微观结构发现,随着氯化钙添加量的增加,两种酶体系中蛋白微粒均凝结得更紧密。本研究结果为细菌凝乳酶在干酪生产中的应用提供了理论依据。  相似文献   

5.
水体恶化是导致池塘水产养殖病害爆发,产量下降的主要因素之一。池塘养殖多采用投饵饲养方式,当残饵和生物排泄量超过池塘的自净能力,有机物便不能被完全分解而沉积池底,使池水趋于富营养化,池水中厌氧层不断增厚,造成有毒害作用的氨、亚硝酸盐等物质的积累,微生态平衡遭到破坏,使鱼虾生长受到影响,病害多发。目前大多采用化学药剂改善水质,虽然在短时间内能发挥一定的作用.但是许多化学药剂不仅会破坏水体微生物结构,且对鱼虾有很强的毒害作用。因此寻找既能净化养殖环境,又不会破坏水体微生态平衡的水质净化方法成为水产养殖业关注的焦点。  相似文献   

6.
枯草芽孢杆菌对盐碱土水分运动和水稳性团聚体的影响   总被引:5,自引:0,他引:5  
为探明微生物在盐碱地改良方面的应用,通过在盐碱土中加入枯草芽孢杆菌,研究不同浓度微咸水(0,1,2,3,4g/L)条件下,盐碱土中的水分运动和土壤水稳性团聚体的变化规律。结果表明:(1)枯草芽孢杆菌可以显著减少土壤的入渗能力,同时可减缓水分的迁移能力,添加枯草芽孢杆菌的土壤与相对应的对照组相比,累积入渗量和湿润锋推进距离均显著减少,其中在微咸水浓度为2g/L时,土壤累积入渗量减少幅度最大,为40.97%,其他处理减少程度依次为3,0,1,4g/L,湿润锋的推进距离也有类似的结果。(2)利用Philip和Kostiakov入渗模型拟合试验数据,发现Philip公式中的吸渗率S均小于相相应对照组,Kostiakov公式中的经验系数K均小于相应对照组,而经验指数β均大于相应对照组。(3)枯草芽孢杆菌可以增加土壤的保水能力,在微咸水浓度为2g/L时,对土壤水吸力的影响较大。与对照组相比,van Genuchten公式中土壤滞留含水率θr、饱和含水率θs及与进气值相关系数α均有所增大,形状系数n逐渐减小。(4)含有枯草芽孢杆菌的土壤,在微咸水入渗后其土壤团粒结构均有较大的改善。  相似文献   

7.
氮肥基追比对冬小麦产量和蛋白质组分及生理指标的影响   总被引:5,自引:1,他引:4  
在大田试验条件下,以A1(中麦8)、 A2(中麦175)和A3(轮选518)3个小麦品种为试验材料,设3个氮肥基追比处理(B1, 底肥∶拔节肥∶开花肥=5∶5∶0; B2, 底肥∶拔节肥∶开花肥=5∶4∶1; B3, 底肥∶拔节肥∶开花肥=5∶3∶2),采用2因素随机区组设计,研究了不同氮肥基追比对冬小麦子粒产量和蛋白质组分及生理特性的影响。结果表明,在底肥和追肥总量相同的条件下,适当提高开花期追施氮肥的比例有利于抑制小麦生育后期旗叶叶绿素的降解,提高叶片含氮量,延长叶片功能期;B3处理子粒产量及容重、 千粒重和蛋白质产量均高于其它两施肥处理,其中B3处理的千粒重显著高于B2处理。品种间各产量因素间差异显著。不同氮肥基追比例对球蛋白含量有显著影响,而对其他蛋白组分含量影响不显著。  相似文献   

8.
为研究磷酸盐和碳酸盐对光发酵产氢过程的影响,该文主要以酶解预处理后的玉米秸秆为产氢基质,对不同浓度的磷酸盐(K_2HPO_4)和碳酸盐(NaHCO_3 )下的氢气产量、pH值、ORP值和产氢动力学结果进行分析。结果表明,当K_2HPO_4的浓度为10 mmol/L时,氢气产量为(40.65±0.35)m L/g,比对照组显著提高了28.48%,对光发酵产氢的促进效果最好;终pH值为6.37±0.02,显著高于对照组的6.06±0.03,能够有效缓冲反应体系的pH值。不同K_2HPO_4浓度下的产氢动力学特性结果表明,适当的K_2HPO_4浓度提高了最大产氢潜能和最大产氢速率,缩短了产氢延迟时间,当K_2HPO_4的浓度为10 mmol/L时,最大产氢潜能最大,和最大产氢速率较大,产氢延迟时间较短,分别是40.81 m L/g、1.87 m L/(h·g)和2.85 h。当NaHCO_3 浓度为5 mmol/L时,氢气产量为(37.46±1.40)m L/g,比对照组显著提高了18.39%,对光发酵产氢的促进效果最好;终pH值为6.26±0.04,显著高于对照组的6.06±0.03,能够有效缓冲反应体系的pH值。不同NaHCO_3 浓度下的产氢动力学结果表明,适当的NaHCO_3 浓度能够提高最大产氢潜能和最大产氢速率,但却会延迟光合细菌的产氢,当NaHCO_3 浓度为5 mmol/L时,最大产氢潜能和最大产氢速率最大,产氢延迟时间相对较短,分别是37.26 m L/g、1.92 m L/(h·g)和5.11 h。该研究可为秸秆类生物质光发酵生物制氢工艺提供参考。  相似文献   

9.
为揭示活塞弹性变形对活塞二阶运动及裙部润滑特性的影响规律,基于有限元法建立活塞和缸套的结构动力学模型,耦合活塞二阶运动方程及裙部流体动力润滑模型,分析活塞弹性对活塞二阶运动和裙部润滑特性的影响。结果表明:不同曲轴转角下活塞主、次推力面的变形不同,做功行程中变形明显,而且最大变形量出现的区域随曲轴转角的变化而改变;考虑活塞弹性变形后,活塞二阶运动一般比不考虑活塞弹性变形有所增加,在压缩和做功行程中增加明显;活塞裙部的最小油膜厚度增加,而总摩擦功耗降低,做功行程中两者变化明显;油膜压力场峰值出现位置及油膜压力分布规律改变,油膜压力场峰值减小。该研究为活塞裙部型线设计及配缸间隙选择提供参考。  相似文献   

10.
[目的]探究微生物在砒砂岩土壤修复工程中的作用,为微生物强化植物改良砒砂岩土壤的科学设想提供新思路.[方法]以黑麦草作为供试作物,通过室内盆栽模拟试验的方法,研究接种植物促生芽孢杆菌Bacillus halotolerans P75,施用腐殖酸肥料以及不同的菌肥搭配对水土流失严重的砒砂岩土壤理化性质及黑麦草生长和抗逆性...  相似文献   

11.
12.
作为生防菌的枯草芽孢杆菌XP(Bacillus subtilis subspecies stercoris strain XP)不仅具有较强的耐硒与耐盐能力,而且还可将毒性较高的无机硒转化为安全性高、生物活性好的纳米硒 (SeNP),然而目前其合成SeNP的效率并不高。为提升菌株XP生物合成SeNP的效率,该研究针对其合成工艺条件做了进一步优化。首先,通过单因素试验,初步筛选出适宜范围量值的初始亚硒酸盐Se (IV)浓度、摇床转速、XP接种量;其次,将这三个因子作为影响因素,以SeNP产量为响应指标,利用Box-Behnken响应面法 (RSM) 进行分析;最终,通过响应面法获得枯草芽孢杆菌XP产SeNP的最优发酵工艺条件。研究结果表明,枯草芽孢杆菌XP合成纳米硒的最佳发酵条件为:初始Se (IV) 3.4 mmol/L、摇床转速157 r/min、菌株XP接种量9.9%,此发酵条件下纳米硒的产量达到1.82 mmol/L,相对优化前提升了60%以上。此外,通过种子发芽试验,进一步证明此工艺条件下合成的纳米硒具有较高的生物活性,可有效提升油麦菜种子活力,促进种子萌发。  相似文献   

13.
A two-year irrigated field study was conducted to determine the effects of plant growth-promoting rhizobacteria (PGPR; Bacillus subtilis OSU-142 and Bacillus megaterium M3) as biofertilizer, and in combination with a chemical nitrogen (N) fertilizer, on turf color and clipping yield, and interaction of biofertilizer and chemical N fertilizers in perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinacea L. Schreb.), and Kentucky bluegrass (Poa pratensis L.). The three turf species were tested separately in split-plot design experiments with three replications. Three fertilizer sources (ammonium nitrate only, ammonium nitrate + B. megaterium M3, and ammonium nitrate + B. subtilis OSU-142) were the main plots. N applications with monthly applications of 0.0, 2.5, 5.0, and 7.5 g N/m2 were the subplots. Color ratings and clipping yields increased with increasing chemical N fertilizers in all species. Both Bacillus sp. significantly increased color ratings and clipping yields in perennial ryegrass and tall fescue. However, there were no significant differences among the three fertilizer sources in color and clipping yield of Kentucky bluegrass. The experiments showed that there is a small but significant benefit from applying biofertilizers for turf color, and that N fertilization may be reduced in some turf species when biofertilization are made for this purpose.  相似文献   

14.
本研究从松嫩平原pH值在10.0以上、植物难以生存的斑块状裸地中分离到一株细菌SA-5,经鉴定该菌株为革兰氏染色阴性,杆状,接触酶阳性,氧化酶阴性,菌落呈橙黄色的好氧细菌,可水解淀粉。抗逆特性分析显示,菌株SA-5可在高达275mmol/L Na2CO3或pH 12.0以及2.0mol/L NaCl培养基中生长,中性条件下生长明显受到抑制,其中对碳酸盐的耐受性远高于普通植物。根据16SrDNA序列等分析结果显示,菌株SA-5属于Bacillus属,仅与菌株Bacillus aurantiacus K1-5T相似性最高,为99%,与其余已发表菌株均低于97%。由以上结果可见,菌株SA-5是Bacillus属中一株嗜碱耐盐菌,并且菌株SA-5对耐碳酸盐基因的开发具有潜在的价值。  相似文献   

15.
Buffer capacity analysis of open atmospheric gas–liquid systems containing main acidic and basic atmospheric pollutants was carried out. Usually the buffer capacity is considered as a function of pH as an independent variable. In this work the buffer capacity is analysed including the dependence of pH on the composition of a system. Such an approach allows finding an important, from the viewpoint of atmospheric water acidification, relationship between the gas phase composition and the buffer capacity. It was found that buffer capacity of the open gas–liquid systems may be very high and it may cause the liquid phase pH to remain at low levels. The buffer capacity of the analysed systems is most strongly affected by the simultaneous presence of ammonia and strong acids in the gas phase. The higher concentrations of strong acid gases the lower NH3 concentration is sufficient to achieve high buffer capacity. In the presence of strong acid gases, calcium ions affect both the buffer capacity and the liquid phase pH only at low NH3 concentrations. High buffer capacity of open gas–liquid systems may be one of the reasons why the reduction in emissions of acidic gas pollutants has little effect on decrease in atmospheric water acidity.  相似文献   

16.
Extensive use of chromium in industry has caused environmental contamination. Chromium-resistant bacteria are capable of reducing toxic Cr (VI) to less toxic Cr (III). Eight isolates, which can grow on LB agar containing 500 mg/L of Cr (VI), were isolated from soil samples of iron mineral area. The bacterial isolates were identified as Bacillus sp. by the 16S rRNA gene sequences. Phylogenetic tree analysis indicates the isolates can be divided into two groups. The bacterial isolates can be resistant to other heavy metals and reduce Cr (VI) at different levels. One bacterial isolate (MDS05), which can tolerate 2500 mg/L Cr (VI) and was able to reduce almost 100% of Cr (VI) at the concentration of 10 mg/L in 24 h, was selected to study the effects of some environmental factors such as pH, temperature, and time on Cr (VI) reduction and growth. The cell growth of MDS05 was affected by the presence of Cr (VI), especially at the concentration of 100 mg/L. It reduced more amount of Cr (VI) under a wide range of concentrations from 5 to 50 mg/L, and reduction was optimum at 37 °C and pH 8. MDS05 showed great promise for use in Cr (VI) detoxification under a wide range of environmental conditions.  相似文献   

17.
为了研究促生菌 Bacillussp. KTS-1-1和 /或氮磷钾复合肥对太子参生长及代谢的影响,试验采用盆栽方式,且设置了 7个处理:T1:KTS-1-1+0.25 g氮磷钾复合肥(100 mL 3×10 8CFU·mL-1菌悬液 +100 mL含 0.25 g复合肥的水溶液);T2:KTS-1-1+0.5 g氮磷钾复合肥(100 mL 3×10 8CFU·mL-1菌悬液 +100 mL含 0.5 g复合肥的水溶液);T3:KTS-1-1+1.0 g氮磷钾复合肥(100 mL 3×10 8CFU·mL-1菌悬液 +100 mL含 1.0 g复合肥的水溶液);T4:2 g复合肥(200 mL含 2.0 g复合肥的水溶液);T5:单独喷施KTS-1-1(200 mL 3×10 8CFU·mL-1菌悬液);T6:浸种(200 mL 3×10 8CFU·mL-1菌悬液);T7:对照(200 mL自来水)。太子参开花后进行喷施处理,一个月后采样测定太子参生长及代谢相关指标。结果表明:与 T4、T7相比,促生菌 Bacillussp. KTS-1-1与氮磷钾复合肥配施可提高太子参生物量;促生菌 Bacillussp. KTS-1-1与低中剂量氮磷钾复合肥配施(T1、T2)有利于太子参叶片碳代谢产物还原糖和叶绿素,氮代谢产物铵态氮、总蛋白质、总氨基酸、硝酸还原酶和抗逆性指标过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APx)、苯丙氨酸解氨酶(PAL)、丙二醛(MDA)、总酚和木质素的改善,且降低植株体内脱落酸含量。因此采用促生菌 Bacillussp.KTS-1-1和减施 75.0%~ 87.5%氮磷钾复合肥配施的方案(T1、T2),既可以促进太子参的生长和碳氮代谢物的积累,同时还可提高其田间抗逆性。  相似文献   

18.
Arthrobacter sp. Sphe3 and Bacillus sphaericus cells were used for Cu(II) biosorption. The effect of contact time, biosorbent dose, equilibrium pH, temperature and the presence of other ions on the efficiency of the process were extensively studied. Optimum pH value and biomass concentration were determined at 5.0 and 1.0?g/l, whereas contact time was found to be 5 and 10?min for Arthrobacter sp. Sphe3 and Bacillus sphaericus biomass, respectively. Equilibrium data fitted very well to Freundlich model (R 2?=?0.996, n?=?2.325, K f?=?8.141) using Arthrobacter sp. Sphe3. In the case of B. sphaericus, a Langmuir adsorption model [R 2?=?0.996, Q max?=?51.54?mg-Cu(II)/g] showed to better describe the results. Potentiometric titration and Fourier transform infrared (FTIR) spectroscopy showed that amine, carboxyl and phosphate groups participate in Cu(II)-binding. The calculated thermodynamic parameters indicated the spontaneous and feasible nature of Cu(II) biosorption on both biosorbents. Selectivity of Cu(II) biosorption was examined in binary and multi-ions systems with various anions and cations which are commonly found in municipal and industrial wastewater. A specificity towards Cu(II) was observed in binary mixtures with Cl-, CO 3 -2 , NO 3 - , SO 4 -2 , PO 4 -3 , Mg+2 and Ca+2, and As(V) with the maximum uptake capacity remaining constant even at high competitive ion??s concentrations of 200?mg/l. Desorption studies showed that Cu(II) could be completely desorbed from Cu(II)-loaded Arthrobacter strain Sphe3 and B. sphaericus biomass using 1.0 and 0.8?M HCl, respectively, and both bacterial species could be effectively reused up to five cycles, making their application in wastewater detoxification more attractive.  相似文献   

19.
A thermophilic nitrifying bacterium, strain T3, was isolated from compost made of animal waste by using a novel selective medium. Strain T3 was classified into the genus Bacillus, close to Bacillus halodurans, but identified as a novel species. To evaluate the effect of adding strain T3 on ammonia emission during the process of composting animal waste, laboratory scale composting was done. Ammonia emission was lower when strain T3 was added than in the control material to which strain T3 was not added. Thermophilic nitrifying bacteria in the strain T3-containing material increased from 6.24 (log value) to 7.55 (log value) on average during the tests. These results suggested the possibility of reducing ammonia emission from composting of animal waste by adding strain T3.  相似文献   

20.
角蛋白酶是一种具有将羽毛酶解为短肽和氨基酸潜力的特殊蛋白酶,对提高羽毛等废弃蛋白质资源的循环利用具有重要价值。芽孢菌产生的角蛋白酶因其分解羽毛能力强且产酶途  相似文献   

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