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1.
目的:探讨黄芩多糖的体外抗氧化活性。方法:从还原力,清除DPPH自由基、超氧阴离子自由基和羟基自由基4个方面研究黄芩多糖的体外抗氧化活性,并与VC进行比较。结果:黄芩多糖对上述自由基均有不同程度清除作用,其还原力较低;清除DPPH自由基的能力略低于VC;对超氧阴离子清除能力强于VC,EC50为0.261 mg/mL;对羟自由基的清除能力弱于VC,EC50为0.724 mg/mL。结论:黄芩多糖具有一定的体外抗氧化能力。  相似文献   

2.
研究考察了茅膏菜水提物和醇提物体外抑菌活性和体外抗氧化活性。对茅膏菜水提物及醇提物采用管碟法测试抑菌效果和Fenton法清除羟自由基(-OH)的清除率。结果表明:茅膏菜水提物及醇提物对沙门氏菌、大肠杆菌和金黄色葡萄球菌生长均有较强的抑制作用;茅膏菜醇提物的抑制效果更为显著;茅膏菜水提物对沙门氏菌、大肠杆菌的最低抑菌浓度(MIC)与最低杀菌浓度(MBC)值相等,为62.50 mg/mL;对金黄色葡萄球菌的MIC与MBC也相同,为125.00 mg/mL;醇提物对沙门氏菌、大肠杆菌的MIC与MBC值相等,为31.25 mg/mL;对金黄色葡萄球菌的MIC与MBC也相同,为15.63 mg/mL。茅膏菜水提物及醇提物对羟自由基有较强的清除作用,其效果随浓度的增加而提高。由此可见,茅膏菜水提物和醇提物有较好的体外抑菌活性和抗氧化活性。  相似文献   

3.
绒毛鹿茸草多糖提取工艺优化及多糖体外抗氧化研究   总被引:1,自引:0,他引:1  
用正交试验法优选绒毛鹿茸草多糖的提取工艺及多糖体外抗氧化研究。在对温度、时间、料水比进行单因素试验的基础上,通过正交试验确定了提取绒毛鹿茸草多糖的最佳工艺条件;通过清除羟基自由基(.OH)和超氧阴离子自由基(O2-.)试验,及模拟胃液条件下清除NO2-试验,研究绒毛鹿茸草多糖体外抗氧化活性。提取最佳工艺条件为:料水比1:20,在100℃下浸提3h,浸提2次;醇沉采用3.5倍体积95%乙醇3h。绒毛鹿茸草多糖浓度在0.4~2.0mg/mL之间时,清除羟基自由基(.OH)呈增长趋势,当浓度达到2.0mg/mL时清除率达45%;多糖浓度在0.1~0.3mg/mL之间时,清除超氧阴离子自由基(O2-.)呈负增长趋势,当浓度达到0.3mg/mL时清除率达-6.39%;多糖浓度在1~5mg/mL之间时清除NO2-呈增长趋势,当浓度达到5mg/mL时清除NO2-能力达到14.3%。对绒毛鹿茸草多糖提取工艺进行研究,可知绒毛鹿茸草多糖清除羟基自由基(.OH)活性较强,有一定清除NO2-能力,能促进超氧阴离子(O2-.)形成。  相似文献   

4.
本试验以枯草芽孢杆菌和大肠杆菌为供试菌,采用滤纸片法研究辣椒碱对细菌的作用效果。试验一结果显示:辣椒碱对枯草芽孢杆菌、大肠杆菌都有抑菌作用。在浸置3 h时,对于枯草芽孢杆菌,当辣椒碱浓度低于1 mg/mL时,辣椒碱对枯草杆菌的抑菌作用随浓度增加而加强,1 mg/mL时抑菌圈直径达到最大,而浓度大于1 mg/mL时,随浓度增加作用效果减弱|而对于大肠杆菌而言,在浓度为0.125 ~ 3 mg/mL时,辣椒碱的抑菌效果随浓度增加显著加强(P < 0.05)。试验二结果显示:在辣椒碱浓度为1 mg/mL时,对枯草芽孢杆菌的作用效果随浸置时间延长出现降低趋势|而对于大肠杆菌,在同一浸置时间辣椒碱的作用效果为3 mg/mL>2 mg/mL>1 mg/mL,而对于同一辣椒碱浓度,随着浸置时间延长,作用效果增强。辣椒碱在浓度低于1 mg/mL 时对枯草芽孢杆菌随浓度增加而增强|浓度大于1 mg/mL时,出现减弱趋势|辣椒碱对大肠杆菌抑菌效果在浓度为0.125 ~ 3 mg/mL时随浓度增加而增强,且随浸置时间延长抑菌效果增强。 [关键词] 辣椒碱|枯草芽孢杆菌|大肠杆菌|滤纸片法|作用效果  相似文献   

5.
本文采用有机溶剂提取技术和分光光度法,对黄酮、多酚类化合物进行提取和测试分析,研究结果表明:新疆雄蚕蛾酒黄酮和多酚类物质含量较高,分别为0.6648 mg/mL和0.4356 mg/mL,具有很高的抗氧化、降血压、防止动脉硬化、抗衰老和清除自由基等医疗保健作用。  相似文献   

6.
为研究东北林蛙卵油脂肪酸的体外抗氧化作用和保湿作用,以东北林蛙卵油脂肪酸为研究对象,分别测定其对DPPH·自由基、ABTS·自由基、羟自由基的清除作用,测定其还原力,并对其体外保水性能进行了测定。抗氧化试验结果表明:林蛙卵油脂肪酸对DPPH·自由基清除作用的IC50为5.08 mg/m L,最大清除率为95.91%;对ABTS+·自由基清除作用的IC50为9.84 mg/m L,最大清除率为98.58%;对羟自由基清除作用的IC50为7.87 mg/m L。其还原力也随着林蛙卵油脂肪酸的溶液浓度的增加而增加。保湿性试验结果为0~12 h,林蛙卵油脂肪酸保湿性极显著低于透明质酸、甘油和1,2-丙二醇,而24 h时,其保湿性与甘油和1,2-丙二醇差异不显著,说明东北林蛙卵油脂肪酸具有持久的保湿效果。根据这两个性能,可以进一步将其应用到抗氧化和保湿型化妆品当中。  相似文献   

7.
为了研究钝顶螺旋藻多糖的抗氧化作用,试验用羟自由基(.OH)测定试剂盒和超氧阴离子自由基(O2.-)测定试剂盒测定了钝顶螺旋藻多糖对自由基的体外清除能力;同时还用总超氧化物歧化酶(T-SOD)测定试剂盒和总抗氧化能力(T-AOC)测定试剂盒测定了钝顶螺旋藻多糖在体内的抗氧化能力。结果表明:在体外,螺旋藻多糖对.OH和O2.-均具有明显的清除作用,以1.0 mg/mL和6 mg/mL的作用效果最显著(P0.05);在体内,钝顶螺旋藻多糖能显著提高小鼠T-SOD和T-AOC水平,其中以625 mg/kg的作用效果最为明显(P0.05)。说明钝顶螺旋藻多糖能够通过提高抗氧化酶的活性提高机体的抗氧化能力。  相似文献   

8.
响应面法优化党参多糖提取工艺及抗氧化活性研究   总被引:3,自引:0,他引:3  
为探究党参多糖最优提取工艺并研究其体外抗氧化活性,以党参多糖提取率为响应值,以提取时间、提取温度和料液比3个因素为自变量,通过Box-Benhnken中心组合法设计3因素3水平试验方案优化提取工艺,并通过DPPH自由基清除能力、羟基自由基清除能力和还原力测定考察党参多糖的抗氧化活性。结果:最佳提取工艺条件为:提取时间2.3 h、提取温度89℃、最佳料液比24 mL/g,在此条件下,党参多糖提取率最高,达到(15.66±0.04)%,与响应面预测值15.83%相近;抗氧化试验表明,党参多糖对DPPH自由基和羟基自由基半清除率(IC50)分别为0.93 mg/mL和0.65 mg/mL,还原力随着党参多糖浓度的增高而增强,浓度为8 mg/mL时达到0.85,表明党参多糖具有较强的体外抗氧化活性。研究结果为党参多糖合理开发和综合利用提供了理论基础。  相似文献   

9.
为了研究昆仑雪菊黄酮提取物(KFE)体外抗氧化活性,采用超声法提取昆仑雪菊中黄酮,乙醇浓度95%、温度40℃、时间15 min,提取3次。经过测定1 g昆仑雪菊粉末中含有0.125 g黄酮。分别用普鲁士蓝还原法、水杨酸法、邻苯三酚自氧化法、DPPH法以及硫代巴比妥酸法测定不同浓度下KFE的还原能力,对羟自由基(·OH)、超氧阴离子(O~(2-))、DPPH自由基的清除能力以及对脂质过氧化的抑制率。结果表明,KFE还原能力随浓度上升而增强,但弱于维生素C;对羟自由基清除能力在110 g/mL最强,清除率为18.72%,高于维生素C;清除超氧阴离子的能力弱;DPPH自由基清除能力在302.5 g/mL最强,清除率为94.47%;脂质体系抗氧化能力在605 g/mL最强,抑制率为54.22%。结果表明,KFE具有一定的抗氧化活性。  相似文献   

10.
《畜牧与兽医》2016,(8):8-11
通过对1,1-二苯基-2-苦肼基(DPPH)、超氧化物阴离子、羟自由基的清除试验,测定硫酸化酵母葡聚糖(s GSC)的抗氧化活性;通过测定s GSC对金黄色葡萄球菌、表皮葡萄球菌、猪链球菌、粪肠球菌、大肠杆菌、耐药金黄色葡萄球菌NY3等的最小抑菌浓度,评价s GSC体外抗菌活性。结果表明:s GSC对DPPH、超氧化物阴离子、羟自由基的清除率均随着s GSC的浓度的增加而增加,在浓度为5 mg/m L时,对3种自由基的清除率分别为89.72%、42.16%、83.41%,表明s GSC对3种自由基均有较好的清除作用,表现出了较好的抗氧化活性。s GSC对金黄色葡萄球菌、表皮葡萄球菌、猪链球菌、粪肠球菌的最小抑菌浓度均为80 mg/m L,而对大肠杆菌为40 mg/m L,表明s GSC对这几种菌具有一定的抑菌作用;而对NY3的最小抑菌浓度大于80 mg/m L,表明s GSC对耐药金黄色葡萄球菌没有抑菌作用。  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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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