共查询到17条相似文献,搜索用时 125 毫秒
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结合碱溶酸沉法对艾叶进行微波处理,以艾叶中总黄酮的提取量为指标,考察微波功率、微波作用时间、溶剂用量、水浸泡时间等因素的影响。结果表明艾叶中总黄酮提取的最佳工艺条件为:用石灰水调pH值至8—9,加入3%的硼砂,溶剂用量为料液比1∶8(mL/g)、浸泡时间20min、微波功率640W、提取时间7min,然后在提取液中加入稀盐酸,调pH值至2—3进行沉降。 相似文献
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采用正交试验比较提取溶剂、料液比、提取温度、超声时间对植物油中苯并芘提取率的影响.结果对植物油中苯并芘提取率的影响程度依次为:提取溶剂>料液比>超声时间>提取温度.最佳提取工艺为:提取溶剂为乙腈,料液比为1∶125,提取温度为50℃,超声时间为2.5h. 相似文献
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以石榴皮为原料,采用超声波辅助提取法对石榴皮多酚的提取工艺进行了研究.通过对提取溶剂的筛选,确定乙醇为提取溶剂,考察液固比、超声处理功率、超声处理温度和处理时间等因素对石榴皮多酚得率的影响,在单因素试验的基础上,进行L9(34)正交试验.结果表明,最佳提取工艺条件为:超声波功率为180W,提取温度为70℃,液固比为15∶1(mg/mL),提取时间为40min,在此条件下石榴皮多酚得率为12.71%. 相似文献
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马占相思树叶中总多酚的溶剂回流提取工艺 总被引:1,自引:1,他引:0
研究了溶剂回流法提取马占相思树叶中总多酚的工艺条件.在单因素试验的基础上,用正交试验法对马占相思树叶中总多酚的溶剂回流法提取工艺进行优选,选用L9(34)进行正交试验,以总多酚的提取量为参考指标,考察乙醇体积分数、料液比、提取时间、提取温度对马占相思树叶中总多酚提取量的影响.得到马占相思树叶中总多酚较佳提取工艺条件为:提取溶剂60%乙醇、提取温度80℃,料液比1:9、提取时间60min,提取次数5次,在此条件下,每克马占相思树叶中可提取总多酚25.71mg,提取物以多酚计的清除DPPH的IC50值为32.573g DPPH/g总多酚. 相似文献
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Curcumin, a dietary phytochemical, has been extracted from rhizomes of Curcuma amada using ultrasound assisted extraction (UAE) and the results compared with the conventional extraction approach to establish the process intensification benefits. The effect of operating parameters such as type of solvent, extraction time, extraction temperature, solid to solvent ratio, particle size and ultrasonic power on the extraction yield have been investigated in details for the approach UAE. The maximum extraction yield as 72% was obtained in 1 h under optimized conditions of 35 °C temperature, solid to solvent ratio of 1:25, particle size of 0.09 mm, ultrasonic power of 250 W and ultrasound frequency of 22 kHz with ethanol as the solvent. The obtained yield was significantly higher as compared to the batch extraction where only about 62% yield was achieved in 8 h of treatment. Peleg’s model was used to describe the kinetics of UAE and the model showed a good agreement with the experimental results. Overall, ultrasound has been established to be a green process for extraction of curcumin with benefits of reduction in time as compared to batch extraction and the operating temperature as compared to Soxhlet extraction. 相似文献
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采用微波辅助萃取-水蒸气蒸馏方法提取中药制剂的有效成分,结合紫外分光光度法测定其含量。以提取六味地黄丸中有效成分丹皮酚为试验对象,探讨了微波辅助萃取的实验条件,优化的实验条件是:以乙醇+水(V/V,1∶2)为萃取溶剂,样品与溶剂比1∶50(W/V),微波功率380W,辐射时间2min。结果表明采用微波辅助水蒸气蒸馏对中药制剂进行预处理,可以明显加快丹皮酚的溶出速率,缩短水蒸气蒸馏的时间,将方法应用于牡丹皮及4种中药制剂中丹皮酚的测定,结果满意。 相似文献
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Hesperidin, an abundant and inexpensive bioflavonoid in Penggan (Citrus reticulata) peel, has been reported to possess a wide range of pharmacological properties. Ultrasonic extraction is an effective technique for the isolation of bioactive compounds from vegetable materials. In this study, the application of ultrasonic method was shown to be more efficient in extracting hesperidin from Penggan (C. reticulata) peel than the classical method. The effects of main ultrasonic-assisted extraction conditions on extraction yields of hesperidin from Penggan (C. reticulata) peel were evaluated, including extraction solvents, solvent volume, temperature, extraction time, ultrasonic power, ultrasonic frequency. Results showed that solvent, frequency and processing temperature were the most important factors for improving the extracting yields of hesperidin. When performed at the same temperature under the same time using three frequencies, methanol as the solvent improved the extraction yield evidently compared with ethanol or isopropanol; by comparison of the frequency influence, the yield of hesperidin was higher at 60 kHz than at 20 kHz and 100 kHz. The optimum ultrasonic conditions were determined as: methanol, frequency of 60 kHz, extraction time of 60 min, and temperature of 40 degrees C. In addition, the ultrasonic power had a weak effect on the yields of hesperidin within the experimental range. Extending ultrasonic treatment times did not result in degradation of hesperidin; the rotary beaker for materials can increase the yields of hesperidin. 相似文献
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Jacques RA dos Santos Freitas L Pérez VF Dariva C de Oliveira AP de Oliveira JV Caramão EB 《Ultrasonics sonochemistry》2007,14(1):6-12
The objective of this work is to discuss the main parameters that influence the sonication extraction of Ilex paraguariensis leaves. For this purpose, the extraction time, solvent polarity, solvent volume, sample mass and particle size were evaluated. Results showed that the main variable affecting the extraction process was the solvent polarity. Though in a less extent, temperature and extraction time also demonstrated to be important parameters, while the other variables did not present a significant influence on the extraction yield. The extracts at the optimized condition were compared with those obtained by maceration, in terms of mass yield and chemical composition. The major compounds identified in the extracts were caffeine and palmitic acid. Some saturated hydrocarbons such as fatty acids, fatty acid methyl esters, phytosterols, and theobromine were also identified in the fractions. 相似文献