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1.
超声波法提取黄芪多糖的工艺研究   总被引:1,自引:0,他引:1  
超声波法提取黄芪多糖.单因素试验考察了提取时间、料液比、温度、pH值时黄芪多糖提取率的影响,并通过正交试验优化了提取黄芪多糖的工艺条件.结果表明,超声波法提取黄芪多糖的最佳条件为时间20 min/次,提取次数2次,料液比1:12,pH值9,温度80℃,黄芪多糖的提取率高达96.6%.该方法具有节省溶剂、省时、节能及提取率高等优点.  相似文献   

2.
为研究超声波时间、超声波温度、超声波功率及料液比对米糠多糖提取率的影响,本研究在单因素试验基础上,以米糠多糖提取率为响应值,采用Box-Behnken中心组合进行三因素三水平试验设计优化米糠多糖的超声波提取工艺。结果表明,最优工艺条件为超声波时间74 min、超声波温度82℃、料液比1∶26(g/mL)、超声波功率250 W,此条件下米糠多糖的提取率为1.4197%。超声波提取法稳定性好,回收率高。  相似文献   

3.
白车轴草多糖提取工艺的研究   总被引:1,自引:0,他引:1  
本试验采取热水浸提法提取白车轴草多糖,研究其最佳提取工艺.以白车轴草为原料,多糖提取得率为指标,分别对4个提取参数:浸提温度、料液比、浸提时间和浸提液pH值进行了单因素试验;然后对上述4个因素采用L9(34)正交试验进行优化.结果表明,白车轴草多糖提取得率随着温度的升高而提高,在100℃时达到最大;料液比、浸提时间和浸提液pH值对多糖得率的影响为单峰曲线,上述条件分别为1:15、4 h和8时多糖得率最高.pH值、料液比、温度和提取时间对白车轴草多糖得率的影响都存在极显著差异(P<0.001),影响多糖得率的各因素主次关系为:pH值>料液比>温度>提取时间,浸提液pH值对白车轴草多糖得率的影响最大.白车轴草多糖的最佳提取工艺参数为:提取时间5 h,料液比1:15,温度100℃,浸提液pH值为9.经验证试验测得,此条件下白车轴草多糖得率为2.26%.试验结果揭示,白车轴草多糖的提取得率受提取工艺(浸提温度、料液比、浸提时间和浸提液pH值)的影响显著,调整提取工艺可获得更高的多糖得率.  相似文献   

4.
试验旨在探究不同提取方法对红甜菜多糖的提取效果。试验以红甜菜为原料,分别采用水提醇沉法和超声辅助水提法,在单因素试验基础上进行正交设计优化其提取工艺,探究液料比、提取温度、提取时间对红甜菜多糖提取率的影响。利用Sevag试剂、活性炭和石油醚依次对粗多糖进行纯化。结果表明,采用水提醇沉法时,在液料比90 mL/g、提取温度70℃、提取时间1.5 h的条件下,红甜菜多糖得率最高,提取率达2.33%;采用超声波辅助水提法的最佳提取工艺为液料比40 mL/g、提取温度40℃、提取时间30 min。在此条件下,提取率为6.85%。超声波辅助水提法提取红甜菜多糖中蛋白质去除率、色素去除率、脂肪去除率分别为29.73%、3.88%、2.76%。研究表明,超声波辅助水提法所用提取溶剂少、耗时短、所需温度低、提取率高,更适用于红甜菜多糖的提取。  相似文献   

5.
蒙古口蘑菌丝体多糖的测定   总被引:12,自引:0,他引:12  
该文对蒙古口蘑中可溶性多糖的提取工艺进行了研究,通过单因素试验,研究了料液比、温度、时间、重复提取次数对多糖提取率的影响.结果显示,温度和料液比是影响多糖提取率的主要因素,最佳料液比为1:50.提取温度为85℃,提取时间为2h,重复提取次数为2次.在最佳提取工艺时,蒙古口蘑Tr-海和Tr-12的多糖含量分别为6.63%和6.40%.  相似文献   

6.
王红利  张立 《广东饲料》2014,23(9):37-39
研究了超声波时间、超声波温度、超声波功率及料液比对米糠多糖提取率的影响。在单因素的基础上,以米糠多糖提取率为指标,采用正交试验设计优化了米糠多糖的超声波提取工艺。最优工艺条件为:超声波时间75min,超声波温度80℃,料液比1:25g/mL、超声波功率250W,此条件下米糠多糖的提取率为1.4061%。  相似文献   

7.
试验研究减压内部沸腾法提取青稞中非淀粉多糖的最佳工艺,为青稞多糖产品的开发和利用提供参考.先用乙醇解吸物料,再用蒸馏水提取,考察乙醇体积分数、料液比、真空度、提取时间和提取温度对青稞非淀粉多糖提取率的影响,在单因素试验的基础上进行正交优化.结果表明,减压内部沸腾法提取青稞中非淀粉多糖的最优工艺条件为:乙醇体积分数50%,料液比1:25(g/mL),真空度0.04 MPa,提取时间8 min,提取温度80℃,在此条件下青稞非淀粉多糖的平均提取率为6.45%.试验表明:减压内部沸腾法提取青稞中非淀粉多糖耗时短、能耗低,可应用于谷物多糖成分的提取,具有较好的生产前景.  相似文献   

8.
为了优化灰兜巴粗多糖的提取工艺,利用水提醇沉法提取灰兜巴粗多糖,主要通过考察提取温度、提取时间和料液比3个因素,以灰兜巴多糖提取率为指标,用正交试验优化粗多糖提取工艺。结果提取温度为90℃,提取时间为1.5 h,料液比为1∶10时灰兜巴多糖提取率最高。表明温度对灰兜巴多糖提取率影响显著,其次是时间。验证试验证实该工艺稳定可行,多糖提取率高。  相似文献   

9.
为了提高复方中草药多糖成分中复方板蓝根的粗多糖得率,试验采用水提醇沉法对提取工艺进行优化,首先采用单因素试验设计,分别考察液料比、提取温度、提取时间和醇液比对粗多糖提取率的影响;其次在单因素试验的基础上,通过四因素三水平的正交分析试验获得最佳的提取工艺。结果表明:单因素优化结果为液料比15∶1、提取温度70℃、提取时间1 h、醇液比4∶1;通过正交分析获得最佳的提取条件为液料比15∶1、提取温度80℃、提取时间0.5 h、醇液比4∶1。提取工艺优化后,复方板蓝根的粗多糖得率为10.25%,较优化前复方板蓝根粗多糖得率(6.54%)提高了3.71%。说明本试验可为复方板蓝根多糖后期开发利用提供借鉴。  相似文献   

10.
为了开发新的食用蛋白质资源,本试验以“青大1号”紫花苜蓿新品系青干草为原料,采用酸化加热法配合加盐法提取叶蛋白.单因素试验设计,分别考察料水比、加盐量、絮凝时间、pH、预浸时间、絮凝温度6个因素对粗蛋白质提取率的影响,并以单因素试验结果为依据,采用四因素(料水比、加盐量、絮凝时间、pH)三水平L9(34)正交试验设计进行提取工艺优化.试验结果表明:影响粗蛋白质提取率的因素,从大到小依次为料液比、絮凝时间、pH、加盐量.当絮凝温度为70℃、料液比为1∶10、加盐量1%、絮凝时间5min、pH为4时是叶蛋白提取的最优提取条件.  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.
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   

14.
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   

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.
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   

17.
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   

18.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

20.
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   

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