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1.
[目的]研究菊科植物猪毛蒿醇提物的最佳提取工艺条件。[方法]采用冷凝管回流提取法,以乙醇作为提取溶剂,以提取温度、乙醇浓度、料液比、提取时间为关键提取条件,采用四因素三水平设计正交试验,根据提取物得率确定猪毛蒿醇提物的最佳提取工艺。[结果]分析方差和极差R值表明,4个因素对猪毛蒿醇提物得率影响的主次顺序是:提取温度>乙醇浓度>提取时间>料液比;提取温度对提取物得率影响差异极显著(P<0.01),是影响猪毛蒿乙醇提取效果的主要因素,乙醇浓度、料液比、提取时间对提取物得率影响差异不显著(P>0.05),是影响提取效果的次要因素。确定猪毛蒿有效成分的醇提物最佳提取工艺条件是:乙醇浓度65%,料液比1∶7,提取温度75 ℃,提取时间3.0 h。[结论]在实验室条件下,确定了猪毛蒿醇提物的最佳提取工艺条件,为猪毛蒿提取物及其生物活性成分的进一步研发与应用提供了参考。  相似文献   

2.
为了探索超声波辅助提取急弯棘豆黄酮的最佳工艺条件,试验以急弯棘豆黄酮的含量为考察指标,通过单因素和正交实验设计试验研究提取超声功率、温度、时间、乙醇浓度、料液比对急弯棘豆黄酮提取率的影响,筛选出最佳提取工艺。结果表明,影响急弯棘豆超声辅助提取的主要因素依次为超声功率、温度、超声时间和料液比。超声波辅助提取弯棘豆黄酮最佳提取工艺条件:乙醇浓度在60%,超声时间为45min,超声波功率为800 W,温度45℃,料液比为1∶10。最高提取率为1.97%。  相似文献   

3.
为优化豆薯多糖的提取工艺,在单因素试验的基础上,选取超声时间、水料比、超声功率和水提温度作为优化因素,根据Box-Behnken试验设计原理,进行四因素三水平试验。利用响应面分析方法,建立豆薯多糖得率的多元二次回归方程,并得到最佳提取工艺条件。结果表明:当工艺条件为超声时间20.33 min、水料比20.96 m L/g、超声功率395.9 W、提取温度67.56℃时,豆薯多糖的理论最高得率为8.40%,验证值为8.28%。  相似文献   

4.
本实验研究了苦荞壳和苦荞籽中总黄酮的超声提取工艺。在单因素实验研究的基础上通过正交实验优化了提取工艺条件。优化所得最佳超声提取苦荞壳总黄酮工艺条件为:乙醇体积分数60%,超声功率200W,超声时间60min,料液比1:25g/m L,超声温度60℃;最佳苦荞籽总黄酮提取工艺条件为:乙醇体积分数60%,超声功率200W,超声时间50min,料液比1:25g/m L,超声温度60℃。对应的最佳提取条件下,苦荞壳和苦荞中总黄酮的提取率分别为4.052%、6.559%、苦荞壳中总黄酮含量丰富,作为苦荞的副产物完全可以在饲料中开发利用,提高苦荞壳的经济价值。  相似文献   

5.
为了优化白僵蚕卵磷脂的最佳超声提取工艺。采用单因素和r9(3^3)正交设计,以白僵蚕卵磷脂得率为指标,优选白僵蚕卵磷脂的提取方法。结果表明:最佳提取条件为超声功率200W,超声辅助提取时间40min,料液比1:3[m(料):V(液)=1:3]。结果显示,确定的最佳工艺所得的白僵蚕卵磷脂含量较高,比常规溶剂提取法得率高2...  相似文献   

6.
本文研究了苦荞壳和苦荞籽中总黄酮的超声提取工艺。在单因素实验研究的基础上通过正交实验优化了提取工艺条件。优化所得最佳超声提取苦荞壳总黄酮工艺条件为:乙醇体积分数60%,超声功率200 W,超声时间60 min,料液比1:25 g/m L,超声温度60℃;最佳苦荞籽总黄酮提取工艺条件为:乙醇体积分数60%,超声功率200 W,超声时间50 min,料液比1:25 g/m L,超声温度60℃。对应的最佳提取条件下,苦荞壳和苦荞中总黄酮的提取率分别为4.052%,6.559%,苦荞壳中总黄酮含量丰富,作为苦荞的副产物完全可以在饲料中开发利用,提高苦荞壳的经济价值。  相似文献   

7.
为了对马齿苋抑菌物质的超声波辅助提取工艺进行优化,试验首先采用单因素试验方法研究提取时间、提取温度、乙醇浓度、液料比、超声功率对马齿苋抑菌物质提取的影响,然后在单因素试验基础上,选取响应面优化法的三个影响因素,以抑菌圈直径为响应值,采用三因素三水平响应面优化法对马齿苋抑菌物质的超声波辅助提取工艺进行优化,确定最佳提取工艺参数后进行实际验证。结果表明:单因素试验得到最佳提取时间为80 min,提取温度为70℃,乙醇浓度为80%,液料比为10∶1(mL/g),超声功率为390 W。选取了液料比、乙醇浓度、超声功率作为响应面法的优化因素。响应面优化法得到的各因素的主效应关系为超声功率液料比乙醇浓度,确定最佳提取条件为乙醇浓度65%、超声功率360 W、液料比5∶1(mL/g),在此条件下检测获得的抑菌圈直径为15.221 mm,与理论最佳值15.533 mm差异较小。说明试验成功优化了马齿苋抑菌物质的超声波辅助提取工艺。  相似文献   

8.
研究旨在探讨采用超声波强化水蒸气蒸馏法提取薰衣草精油的最佳提取条件。通过单因素试验和二次回归正交试验,以超声强化时间、超声功率、液固比、提取时间作为主要影响因素,确定超声强化水蒸气蒸馏提取薰衣草精油的最佳提取工艺条件。结果表明:提取薰衣草精油的最佳工艺条件为超声强化时间17.6 min、超声功率171.0 W、液固比16.6:1、提取时间1.51 h。在该条件下,薰衣草精油得率的期望值是0.761%。通过验证试验,5个重复试验的薰衣草精油的得率为0.751%、0.761%、0.771%、0.773%、0.786%,平均值为0.768%。验证试验的平均值与理论的期望值(0.761%)非常接近,表明所选的工艺条件可行。  相似文献   

9.
为研究大果木姜子黄酮的最佳提取工艺及其抗氧化效果,本试验以大果木姜子为研究对象,通过单因素试验分析了提取时间、超声功率、液料比、乙醇浓度和超声温度对大果木姜子黄酮含量和抗氧化活性的影响,在此基础上,采用总评归一-响应面法优化出的最佳提取条件进行验证。结果表明:大果木姜子黄酮最佳提取条件为液料比40:1(mL/g),提取时间35 min,超声功率60 W,此条件下黄酮含量为2.48%,对DPPH自由基清除活性为93.18%。经总评归一-响应面优化得到的超声提取工艺稳定、可靠,可用于大果木姜子黄酮的提取,且具有较好的抗氧化活性。 [关键词] 大果木姜子|黄酮|响应面|抗氧化  相似文献   

10.
以水作为提取剂,采用超声提取竹叶黄酮,并对提取工艺进行优化,实验探究超声时间、超声温度、超声功率、料液比等因素对提取效果的影响,在此基础上,通过正交优化了竹叶黄酮的提取工艺,所得的最佳工艺参数为:超声时间60min,料液比1∶17g/mL,超声温度60℃,超声功率200W,此条件下竹叶黄酮的提取率达4.692%。超声提取竹叶黄酮用作饲料添加剂高效安全,可进一步工业化推广。  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.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

13.
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   

14.
15.
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   

16.
A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.  相似文献   

17.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

18.
The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.  相似文献   

19.
Bovine Mastitis in Selected Areas of Southern Ethiopia   总被引:3,自引:0,他引:3  
A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.  相似文献   

20.
不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响   总被引:2,自引:0,他引:2  
本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。  相似文献   

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