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1.
本试验采用响应面法优化超声波辅助提取野生酸枣仁中总黄酮的提取工艺。通过单因素试验考察了乙醇浓度、浸泡时间、超声温度和超声时间对酸枣仁总黄酮提取率的影响,并在此基础上通过响应面法获得野生酸枣仁总黄酮的最佳提取工艺。结果表明,野生酸枣仁总黄酮的最佳提取工艺条件为:乙醇浓度64.46%、浸泡时间12 h、超声时间44.02 min、超声温度62.86℃,在此工艺条件下酸枣仁总黄酮理论提取率为1.00984%,实际总黄酮提取率为0.9269%。  相似文献   

2.
目的:通过星点设计-效应面法优选金桑芪抗毒滴丸的提取工艺。方法:以乙醇体积分数、乙醇用量、提取时间为自变量,以总黄酮含量和干膏收率的总评归一值为因变量,通过对自变量各水平进行二项式拟合,应用效应面法优选提取工艺,并进行预测分析。结果:最优提取工艺为加7倍量43%乙醇回流提取2次,每次95 min。结论:星点设计-效应面法优选的金桑芪抗毒滴丸提取工艺简便、可行。  相似文献   

3.
为了研究板蓝根多糖的提取工艺,试验采用水浸提法、超声波法和酶解法提取板蓝根多糖,得出提取效率较高的方法。再利用L9(33)正交试验优选出板蓝根多糖的最佳工艺条件。结果表明,超声波法对板蓝根多糖的提取的多糖含量和提取率分别达到3.386mg/mL和6.512%,显著高于水浸提法和酶解法。正交试验得出板蓝根多糖提取的最佳工艺条件为:料液比1:20(g/mL),超声温度为90℃,超声时间为30 min。该工艺为提高板蓝根多糖的提取效率提供了实验基础,并为进一步工业化生产提供了参考依据。  相似文献   

4.
正交试验法优选女贞子中特女贞苷的提取工艺   总被引:1,自引:1,他引:0  
张艳  伍勇 《中国兽药杂志》2012,46(10):33-35
采用正交试验法优选女贞子中特女贞苷的最佳提取工艺条件,以加水量、提取时间与提取次数为考察因素,特女贞苷含量为评价指标对提取工艺进行考察。结果显示,特女贞苷的最佳提取工艺为加10倍药材质量的水,提取3次,每次2 h。该工艺为提高特女贞苷的提取率提供了实验基础,并为进一步的工业化生产提供科学的理论依据。  相似文献   

5.
正交设计法优化淫羊藿多糖的提取工艺   总被引:1,自引:0,他引:1  
为了优选淫羊藿多糖的最佳提取工艺条件,通过单因素试验和正交试验,以料水比、提取时间、提取温度和提取次数为考察目标,以多糖提取率为评价指标,优选最佳提取工艺。结果表明,淫羊藿多糖最佳提取工艺为料水比为1∶25,提取时间2h,提取次数为3次,提取温度为90℃。多糖醇沉浓度为700mL/L。该工艺为淫羊藿多糖的提取奠定了基础,并为进一步的工业化生产提供了科学依据。  相似文献   

6.
本试验以马勃多糖得率为评价指标,通过研究提取温度、时间、酶用量、p H对多糖提取率的影响,以单因素试验和正交试验设计优选最佳提取工艺条件。结果表明:蜗牛酶辅助提取马勃多糖的最佳提取工艺条件为提取温度35℃、提取时间120 min、酶用量5.0%、p H 6.0。在此条件下,马勃多糖得率为0.908%。与传统水提法相比,多糖得率提高了158.01%。由此可见,蜗牛酶辅助提取具有得率高、提取时间短、条件温和等优点。  相似文献   

7.
为优化浮萍多糖的提取工艺,基于单因素试验结果对影响浮萍多糖提取率的三个显著因素及水平:料液比(1∶40、1∶50、1∶60)、超声时间(40 min、60 min、80 min)和超声功率(300 W、350 W、400 W)进行了研究。以浮萍多糖提取率为响应值,运用Design-Expert软件进行响应面设计并开展试验,通过工艺优化确定浮萍多糖的最佳提取条件为料液比1∶40.06、超声时间79.58 min、超声功率341.37 W,此条件下浮萍多糖提取率的理论值可达到1.188%;验证试验的浮萍多糖提取率为1.125%,与理论值仅相差0.063%。优化后的提取工艺条件准确可靠,可用于实际操作。  相似文献   

8.
本实验通过单因素实验和星点设计-效应面法优化超声酶法提取蓝莓中花青素的工艺。以酶种类、酶用量、提取时间、提取温度、料液比、醇浓度和pH值为因素,以花青素提取率为指标,进行提取工艺的单因素优化;在单因素实验基础上,通过星点设计-效应面法,考察联合提取时体系中醇浓度,提取时间,料液比对提取结果的影响,从而确定了酶-辅助超声法提取蓝莓中花青素的最佳工艺为:β-葡聚糖酶,提取时间为20min,料液比为1:20,然后往体系中补充无水乙醇,使得体系中的醇浓度为55%,再继续超声提取10min。花青素提取率可达到19.156%,提取条件温和,酶用量小,提取率高,可为蓝莓中花青素的深度开发提供科学依据。  相似文献   

9.
试验采用微波辅助提取不同季节女贞子中齐墩果酸。在单因素试验的基础上,通过正交试验对不同季节女贞子中齐墩果酸的提取条件进行优化。结果表明:6月份女贞子中齐墩果酸最佳提取工艺条件为乙醇体积分数80%,料液比1∶12(g/mL),微波时间3 min,微波功率300 W,微波温度50℃,此条件下齐墩果酸提取率为2.82%;9月份女贞子中齐墩果酸最佳提取工艺条件为乙醇体积分数60%,料液比1∶14(g/mL),微波时间4 min,微波功率300 W,微波温度60℃,此条件下齐墩果酸的提取率为3.11%。  相似文献   

10.
目的:优化石菖蒲挥发油的提取工艺。方法:采用水蒸气蒸馏法提取石菖蒲挥发油,选取挥发油得率为因变量,以三因素五水平星点设计考察浸泡时间、液料比和提取时间对提取工艺的影响,运用效应面法优选提取工艺,并进行预测分析和验证试验。结果:评价指标的二项式拟合方程(r=0.924 4)优于多元线性回归方程(r=0.759 3),优化后的提取工艺为浸泡时间2.78 h、液料比9.09、提取时间6.15 h,挥发油平均得率1.58%。结论:星点设计优化石菖蒲挥发油的提取工艺具有良好的预测性。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
16.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

17.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

18.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

20.
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