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1.
试验以油莎豆粕为原料,采用纤维素酶辅助提取油莎豆粕中的淀粉,并对提取条件进行优化,获得高提取率淀粉。以淀粉提取率为评价指标,在单因素试验的基础上选择加酶量、酶解时间、酶解温度、pH 4个主要影响因素进行正交试验,确定最佳的提取工艺条件。结果表明:加酶量、酶解温度以及酶解时间与酶解温度的交互作用对淀粉提取率有显著影响,油莎豆粕淀粉的最佳提取工艺条件为加酶量1.25%、酶解温度47℃、pH 5.5、酶解时间为5 h,淀粉提取率为77.67%。  相似文献   

2.
试验以探讨确定羊肠膜蛋白粉生产小肽适宜酶解工艺条件为目的。以羊小肠黏膜为原料,利用碱性蛋白酶对其进行酶解试验,采用正交试验对酶解条件(酶添加量、酶解时间、酶解温度和pH)进行优化,以小肽和水溶蛋白为检测指标,探讨最佳酶解工艺条件。结果表明:羊肠膜蛋白粉最佳酶解条件为温度60℃、酶加量5 000 IU/g、pH 10和水解时间4 h。  相似文献   

3.
为寻找一种能够科学高效地将小站稻秸秆用于秸秆还田的方法,并将其作为一种储备技术,本研究通过测定已有6组秸秆降解复合菌系的羧甲基纤维素酶活力和滤纸酶活力,筛选出2组复合菌系,并通过正交试验进行产酶条件的优化,以探索解决小站稻秸秆清洁生产技术的应用问题,保障小站稻的未来绿色可持续发展,为小站稻秸秆高效处理的研究提供理论基础和技术支持。本研究结果表明:复合菌系B和复合菌系F的综合酶活力均高于其他复合菌系;复合菌系B羧甲基纤维素酶最佳发酵条件为25℃,pH 8.0,接种量2%,温度为酶活力主要影响因素;复合菌系B滤纸酶最佳发酵条件为20℃,pH 9.0,接种量2%,pH为酶活力主要影响因素;复合菌系F羧甲基纤维素酶最佳发酵条件为25℃,pH 8.0,接种量2%,温度为酶活力主要影响因素;复合菌系F滤纸酶最佳发酵条件为20℃,pH9.0,接种量2%,接种量为酶活力主要影响因素。  相似文献   

4.
拟康氏木霉固态发酵产纤维素酶系的研究   总被引:1,自引:0,他引:1  
以稻草秸秆为主要原料,利用拟康氏木霉3.3002(Trichoderma pseudokoningii 3.3002)固态发酵生产纤维素酶,对培养条件进行了优化,并系统地测定了各种纤维素酶的酶活.结果表明,最优产酶培养基组成为:稻草秸秆和麸皮的混合比例为4:1,最佳氮源为2.5%(NH4)2SO4,最佳发酵时间120 h,培养温度35℃,接种量15%,pH 5.0,培养基含水率50%.在此条件下,该菌株产纤维素酶系中羧甲基纤维素酶(Cx)酶活力达4700 U/mL,葡聚糖外切酶(Cb)酶活力达3440 U/mL,葡萄糖内切酶(C1)酶活力达到1620 U/mL,滤纸酶(FPA)酶活力达到1935 U/mL.  相似文献   

5.
复合酶法提取松针粉挥发油的研究   总被引:7,自引:0,他引:7  
本试验主要研究利用复合酶提取松针粉的有效成分挥发油,以建立一套行之有效的使用复合酶提取中草药方法,为推广应用复合酶法在提取中草药生产上提供理论依据.试验分为三部分,即常规蒸馏提取试验、单因子试验、多因子试验.其中单因子试验从酶解温度、酶解作用时间、pH、加酶量4个因素考察酶解对松针粉挥发油提取量的影响,多因子试验采用4因素(pH、酶解温度、酶解作用时间、加酶量)三水平做正交试验,确定复合酶法提取松针粉的最佳反应条件.由正交试验得出最佳酶解反应条件是:酶解温度为50℃,pH值为4.5,酶解时间为6h,加酶量为4%.最后对加酶和未加酶组进行t检验比较,结果显示复合酶法提取松针粉有效成分挥发油比常规的提取量高出37.9%,两种方法差异极显著,有效地证明了复合酶可以加大松针粉有效成分的提取量.  相似文献   

6.
酶解蚕蛹蛋白制备血管紧张素转换酶抑制肽的工艺优化   总被引:2,自引:0,他引:2  
采用碱性蛋白酶水解蚕蛹蛋白,制备血管紧张素转换酶(angiotensin-converting enzyme,ACE)抑制肽,是蚕蛹蛋白深度开发的途径之一。以ACE抑制率为响应值,用响应面分析法研究酶解温度、酶解pH和加酶量等因素对酶解产物的ACE抑制活性的影响,优化制备工艺。结果表明,各因素对制备ACE抑制肽的活性影响程度由大到小依次为酶解pH、酶解温度、加酶量。获得碱性蛋白酶水解蚕蛹蛋白制备ACE抑制肽的最佳工艺条件为:酶解温度50.8℃,酶解pH 9.0,加酶量3 500 U/g。在此条件下,蚕蛹蛋白酶解产物对ACE的理论抑制率最高可达96.67%,验证值为96.49%±1.75%,IC50值为0.102 mg/mL,预测模型可靠性高,可应用于蚕蛹ACE抑制肽的酶法制备。  相似文献   

7.
研究复酶对羽毛蛋白尤其是对角蛋白的降解效果。选择复酶酶解温度、酶解液pH、复酶添加量和酶解时间为因素水平,采用L9(34)正交试验设计,对酶解条件进行优选。确定最佳酶解参数:酶解液初pH为7,酶解温度为45℃,酶解时间为32h,复酶添加量为0.006g。结果表明:在试验确定的最佳酶解条件下,羽毛降解率达到了90.87%,酶解液可溶性蛋白的含量达到848.1mg/L,酶解上清液中蛋白分布在20.1~66.2ku,酶解羽毛蛋白体外消化率达到82.83%。  相似文献   

8.
试验以羽毛粉为原料,对羽毛蛋白酶解的条件进行初步研究。以紫外分光光度计测得吸光度值为指标,得出酶解的最佳条件。进行单因素试验,以水解温度、加酶量、水解时间和pH作为4个因素,通过试验筛选每个单因素较好的数值。试验结果表明,最适酶解条件为水解温度60℃、加酶量2.5%、水解时间6 h和pH 6.5。  相似文献   

9.
试验旨在探究油菜秸秆最佳的预处理工艺及其发酵产酶的效果。在油菜秸秆粉末预处理中,以秸秆保留量、预处理秸秆酶解产糖量、初始秸秆比产糖量为预处理的评估指标,考察浸泡时间、处理液浓度、液料比、处理液、秸秆粉碎程度等5个因素对预处理后秸秆粉末的影响,通过正交试验确定出最佳预处理工艺,以浸泡温度、浸泡时间、处理液浓度作为考察因素。结果显示:通过单因素和正交试验优化得到最佳预处理的条件为以40~60目的油菜秸秆粉为原料,液料比10 mL/g,温度45℃,在1.1%的NaOH中浸泡36 h。在最优条件下,秸秆比产糖量达0.181 1 g/g。在固态产酶优化试验中考察碳源配比、氮源浓度、液料比、接种量、培养温度、培养时间等6个因素对固态发酵产酶优化的影响,通过正交试验确定出最佳固态发酵产酶优化条件,以碳源配比、氮源浓度、培养温度、培养时间作为考察因素。通过单因素和正交试验优化,得到最佳发酵条件为油菜秸秆粉和麸皮比为5∶4、硫酸铵浓度为2.5%、液料比1.5 mL/g、接种量5%、培养温度30℃、培养时间5 d,产纤维素酶活提高至7.923 IU。研究表明,通过对油菜秸秆进行预处理及产酶发酵后,能够显著...  相似文献   

10.
本实验采用还原糖法研究了不同酶解时间、温度、pH值及酶浓度条件对纤维素酶酶解小麦麸皮效果的影响。结果表明,纤维素酶酶解小麦麸皮的最适条件为:酶解时间15min,温度37℃,pH值6,最适酶浓度0.04IU/mL。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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