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1.
为寻找高效纤维素降解菌,用于蚕沙及桑树废弃枝条等的加工处理,本研究以羧甲基纤维素钠(CMC-Na)为唯一碳源,从西南大学校园土壤中分离纤维素降解菌。结合测定菌株在羧甲基纤维素钠平板上形成水解圈直径与其菌落直径的比值,及胞外酶活测定法(DNS法)筛选获得一株纤维素酶高产菌株SWU6。该菌株24h发酵液上清液经DNS法检测纤维素酶活力达到136.24U/mL。菌种鉴定结果表明SWU6菌株为革兰氏阳性芽孢杆菌;过氧化氢酶、硝酸盐还原呈阳性;能水解淀粉、液化明胶。基于16SrDNA的系统发育分析结果表明SWU6菌株与登录号为NR 116240的甲基营养型芽孢杆菌(Bacillus methylotrophicus)处于进化树的同一最小分支。综合菌体及菌落形态特征、生理生化实验结果以及基于16SrDNA的系统发育分析,将SWU6菌株鉴定为甲基营养型芽孢杆菌(Bacillus methylotrophicus)。  相似文献   

2.
α-淀粉酶产生菌的分离筛选与诱变选育   总被引:1,自引:0,他引:1  
从土样、水样和面样中分离产α-淀粉酶的芽胞杆菌,对3个样品进行淀粉平板分离和革兰氏染色、芽胞染色,选出产α-淀粉酶芽胞杆菌10株(土样4株、面样3株、水样3株).同时测得其水解圈直径与菌落直径的比值,均在1.9~2.6之间,通过产淀粉酶液体培养基发酵产酶,采用比色法测定发酵液中α-淀粉酶活力均在4.8~5.7 g/mL之间.以筛选出产酶活力较高的菌株为出发菌株,进行紫外线诱变选育,经过大量筛选得到优良菌株,在适宜条件下经过发酵其α-淀粉酶活力可达9.6~13.0g/mL,较出发菌株酶活力提高了69.9%~129.5%.  相似文献   

3.
试验从青藏高原高寒草甸土壤中筛选低温降解纤维素的菌株,探究酶学性质.采用刚果红染色法(水解圈法)和3,5-二硝基水杨酸(DNS)法对菌株所产纤维素酶和木聚糖酶进行酶学性质分析,采用形态学和分子生物学进行菌种鉴定.结果 显示,从高寒草甸土壤样品中筛选出一株能同步产生低温纤维素酶和低温木聚糖酶的菌株FY8,经鉴定该菌株为枝...  相似文献   

4.
采用刚果红平板筛选法从动物粪便中分离和筛选高产β-葡聚糖酶的菌株,选取水解圈直径与菌落直径比值较大的菌株进行酶活力的测定,得到一株酶活力较高的菌株T-4-3,酶活力达到21.9 U/mL。对该菌株进行形态观察和生理生化特征分析,初步鉴定为芽孢杆菌属(Bacillus sp.),将其16S rDNA序列与GeneBank中已知标准菌株的16S rDNA序列进行比对,并用Neighbor-joining方法构建菌株T-4-3进化树,结果表明,T-4-3与标准菌株CP000560 Bacillus amyloliquefaciens聚于同一分支,同源性高达100%。  相似文献   

5.
从实验室保存的83株芽胞杆菌中初筛出11株具有解无机磷能力的菌株,通过平板法进行初筛,根据溶磷圈直径和菌落直径比值大小筛选出溶磷圈直径和菌落直径比值较大的菌株3株,进一步通过液体摇瓶培养复筛出1株分解无机磷能力最强的菌株ZP。对筛选到的3株解无机磷能力强的菌株进行固体发酵培养,研究不同培养基配方及发酵时间与菌株解磷能力之间的关系,以期为生产解磷菌制剂提供理论依据。  相似文献   

6.
从采集于白酒生产环境的样品中经纤维素刚果红平板透明圈法初筛,共获得51株有明显水解圈的菌株,进一步采用酒糟粉刚果红平板透明圈法复筛,获得Dc值(水解圈与菌落的直径比值)较大的15株菌株,并将其置于55℃高温下培养,最终获得2株高温纤维素分解菌,分别编号为X-MZ-2和X-MC-2,经白酒糟固体发酵试验和产酶分析,结果表明:菌株X-MZ-2和X-MC-2在高温条件下的发酵产物中纤维素酶活分别达到13.71和9.25 U/g,同时具有一定的蛋白酶活和液化酶活。采用形态学和分子生物学方法进行初步鉴定,X-MZ-2为地衣芽孢杆菌,X-MC-2为枯草芽孢杆菌。研究为白酒糟发酵饲料的生产提供良好的菌种源。  相似文献   

7.
肉牛粪污中纤维素降解菌的分离筛选   总被引:1,自引:0,他引:1  
为了获得有效降解肉牛粪污中纤维素的细菌,采用以羧甲基纤维素钠为碳源的方法对牛粪及其自然堆肥样品进行纤维素降解菌的分离,对已分离菌株进行形态学和分子生物学鉴定,再结合纤维素刚果红水解圈测定和滤纸条降解试验做进一步研究。结果表明,以羧甲基纤维素钠为碳源,初步分离得到牛粪样品及堆肥中32株纤维素降解菌,进一步筛选得到有刚果红水解圈菌株4株,分别为XQ-1、XQ-2、XQ-3、XQ-4,其对滤纸条具有一定的降解能力,经16S rDNA鉴定,4株菌株分别为大肠埃希菌(Escherichia coli)、黏质沙雷菌(Serratia marcescens)、雷氏普罗威登斯菌(Providencia rettgeri)和费格森埃希菌(Escherichia fergusonii)。  相似文献   

8.
从葛藤(Pueraria lobata)根际分离出8株具有较强溶解无机磷能力的菌株,溶磷圈法测定菌株的HD/CD值(溶磷圈直径HD,菌落直径CD)在2.14~6.73,液体振荡培养下菌株对磷酸钙的溶解量在72.28~159.15mg/L,菌株培养液pH值较初始培养基的pH值7.0均下降。菌株GTR2和GTR15溶解磷酸钙(分别为159.15mg/L、138.72mg/L)及分泌IAA能力(分别为12.71mg/L、14.44mg/L)均较大,且均为碱性菌株,能在甘露醇等多种碳源上较好生长。综合各菌株的溶磷及分泌IAA能力,菌株GTR2和GTR15有望成为高效微生物磷肥接种剂的优良菌种。  相似文献   

9.
产纤维素酶菌株的筛选与产酶测定   总被引:2,自引:0,他引:2  
为了分离筛选获得高产纤维素酶菌株,试验收集堆肥和林场腐殖层土壤样品,经富集培养后接种于不同的鉴别培养基用于分离细菌、放线菌、真菌,利用羧甲基纤维素钠(CMC-Na)琼脂平板结合革兰氏碘液染色法,通过测定水解圈直径与菌落直径比值(H/C值)初筛纤维素降解菌,通过测定滤纸酶(FPA)和羧甲基纤维素酶(CMC)活性复筛出产纤维素酶能力相对较强的菌株,并测定其酶活性,最后从形态学和分子生物学角度对产酶最高的菌株进行鉴定。结果表明:共筛选出产纤维素酶能力相对较强的细菌6株、放线菌9株、真菌2株;FPA和CMC活性测定显示,分离菌株的FPA活性在5.36~25.86 IU/m L之间,CMC活性在11.56~58.75 IU/m L之间,其中1株真菌的酶活性较高,FPA和CMC活性分别达到25.86 IU/m L、58.75 IU/m L,产酶能力高于在生产中应用的绿色木霉菌,这株真菌鉴定为黑曲霉,该菌可以作为潜在的开发菌种。  相似文献   

10.
为得到具有实际应用价值的高效产蛋白酶菌株,以甘肃省夏河地区深度20~30 m处的土样为基质,以菌株生长出的透明水解圈直径大小与菌落大小之比为基础,进行菌株产蛋白酶的活力测定,从而筛选得到优良菌株.结果表明,自甘肃夏河土壤中分离得到的编号为NWMCC0320的菌株产酶活力最高,为114.21U/mL;经多种有效的菌株鉴定...  相似文献   

11.
12.
采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。  相似文献   

13.
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。  相似文献   

14.
本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。  相似文献   

15.
REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.  相似文献   

16.
用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10~0.82μg/g。表明:蜂蜜应视为天然富硒营养品。  相似文献   

17.
乳酸杆菌益生作用机制的研究进展   总被引:2,自引:0,他引:2  
乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和 Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。  相似文献   

18.
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.  相似文献   

19.
乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.  相似文献   

20.
为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …  相似文献   

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