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沉水植物苦草粗蛋白的提取工艺研究 总被引：2，自引：0，他引：2
苦草是减少水体污染,缓解水体富营养化的一种重要沉水植物,含有丰富的蛋白质。试验研究目的是优选沉水植物苦草粗蛋白提取的最佳工艺。采用碱提酸沉法从苦草中提取粗蛋白,通过单因子试验(单因素:NaOH溶液浓度、固液比、提取温度、提取时间)和L(934)正交试验,对影响粗蛋白的提取工艺进行了研究;同时比较了不同pH值对粗蛋白沉淀的影响。结果显示:苦草粗蛋白的最佳提取工艺条件为NaOH溶液浓度0.12mol/l、固液比1:60、提取温度70℃、提取时间80min,此条件下粗蛋白的提取率为67.62%;调节不同pH值沉淀苦草中粗蛋白时,pH值控制在1.05￣1.51之间可以获得最大的沉淀量;优选的苦草粗蛋白提取工艺效果较好,且稳定可行。 相似文献
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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
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
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为了优化苦参碱的提取工艺,以浸膏收率、苦参总碱含量为评价指标,选择用水量、提取时间及提取次数为考察因素,利用L9（3^4）正交试验法优选出水煎煮法提取苦参总碱的最佳工艺条件为用8倍量水提取3次,每次提取2h,并采用乙醇沉淀及三氯甲烷萃取相结合的方法对苦参粗提物进行纯化,浓缩药液浓度为每毫升1．0g生药时进行醇沉,醇沉后调节药液的pH值至9-11用三氯甲烷萃取3次。优选出的提取工艺稳定、合理、可行。 相似文献
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为了优化酶法辅助超声提取功劳木小檗碱的工艺,在单因素实验基础上,根据Box-Behnken中心组合实验设计原理,采用4因素3水平的响应面分析法,以小檗碱收率为响应值进行回归分析。实验结果表明,酶解最佳工艺条件为：酶解pH值3.5、酶用量10.6 mg/g、酶解温度51℃、酶解时间97 min。在此条件下,小檗碱收率为22.46 mg/g。优选的提取工艺稳定可行、收率高,为功劳木的工业化生产提供参考。 相似文献
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本文采用正交试验优选超声法和闪式提取法提取栀子中栀子苷的最佳工艺，并比较两种最佳工艺的提取效果。以L9（34）分别设计超声法和闪式提取法试验，以不同因素和水平进行考察。采用高效液相色谱法测定栀子中栀子苷的含量，以栀子苷的提取率作为两种方法的评价指标。结果表明：超声法提取率略高于闪式提取法，但综合乙醇浓度、料液比和提取时间等因素，闪式提取法更加高效、省时、环境友好，其最佳提取工艺为提取溶剂30%乙醇，料液比1:50，提取时间3 min，在此条件下，提取率为6.21%。综合比较，闪式提取法更适合提取栀子中的栀子苷，本研究可为栀子在饲料领域的开发利用提供理论基础。
[关键词] 超声法|闪式提取法|栀子|栀子苷|高效液相色谱法 相似文献
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目的：优化复方沙棘和胃胶囊的提取工艺。方法：以紫丁香苷含量和正丁醇浸出物为指标,采用L9（3^4）正交试验,优选最佳提取工艺条件。结果：影响提取工艺的因素依次为：提取次数〉提取时间〉加水量〉浸泡时间。最佳工艺条件为：加10倍量水,提取2次,提取总时间4h（2,2）,浸泡时间40min。结论：该工艺简便、可行,适合于工业生产; 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献