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本研究选取本地桑树叶为原料,采用超声波辅助提取技术,以乙醇溶液为溶剂,考察乙醇浓度、料液比、超声时间及超声温度对桑树叶中类黄酮提取效果的影响,并通过响应面分析法确定了桑树叶类黄酮的最佳提取工艺。试验结果表明超声波辅助提取桑树叶类黄酮的优化条件为乙醇浓度70.85%vol、提取温度70.13℃、料液比1:42.2(g:mL)、超声时间20min。在此条件下,类黄酮得率的预测值4.52%,实际测得桑树叶类黄酮的提取率为4.50%,与模型预测值基本相符。 相似文献
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微波萃取桑叶1-脱氧野尻霉素工艺的研究 总被引:1,自引:0,他引:1
研究利用微波萃取技术提取桑叶中DNJ的方法。以无菌过滤水为溶剂,以微波处理为辅助条件,提取了桑叶中的DNJ,考察微波功率、微波处理时间、固液比和提取次数这些因素对生物碱DNJ得率的影响。确定了最佳提取工艺条件为:微波功率为406W,微波处理时间为1.5min,固液比为1g∶40mL,提取次数为2次。 相似文献
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Yeyuan Chen Haiyan Luo Aiping Gao Min Zhu 《Innovative Food Science and Emerging Technologies》2011,12(3):305-309
Litchi seed has been applied in traditional Chinese medicine since ancient time. Its polysaccharides were prepared by ultrasound-assisted extraction technique and optimized by response surface methodology. The optimal conditions to obtain the highest yield of LSP were determined as follows: 15.0 ml/g of solvent/material ratio, 45.0 min of ultrasonic time and 222 W of ultrasonic power. By structural analysis, arabinose, fructose, galactose, glucose and mannose were detected both in LSPs I and II. A small amount of fucose was only found in LSP II. The monosaccharide composition indicated that LSPs I and II were neutral polysaccharides. The glycosidic linkages between monosaccharides and their relative molar percentages were also identified. Both LSPs I and II eliminated the DPPH radical in a dose-dependent manner. Furthermore, LSP I showed a better DPPH radical scavenging activity than LSP II.
Industrial relevance
The bioactive polysaccharides, derived from plant sources, have attracted much attention by consumers and researchers due to their broad spectra of therapeutic properties and good safety. The structural characteristics of polysaccharides are highly correlated with their bioactivities. In this work, the extraction conditions of water-soluble polysaccharides from litchi seed were optimized by response surface methodology with the assistance of ultrasound. Their structural characteristics and bioactivity were investigated. The results are helpful to utilize litchi seed for food and biomedical application. 相似文献6.
植物多糖是一种重要的生物活性物质,具有抗氧化、增强机体免疫功能和防治心血管疾病等作用。对蓝莓叶多糖进行有效的开发利用,对提高蓝莓叶的经济价值具有重要意义。本文采用热水浸提,醇沉的方法提取蓝莓叶多糖,通过响应面法优化蓝莓叶多糖提取工艺,硫酸-苯酚法测定多糖含量。实验结果表明:提取时间为4.2h,提取温度为85℃,料液比为1∶35(g/m L),5倍体积乙醇醇沉6h时,提取蓝莓叶多糖的能力最佳。在此工艺条件下得到蓝莓叶多糖的提取量为29.2mg/g。本实验从蓝莓叶中提取多糖,为今后进一步研究与开发蓝莓叶资源提供了理论依据。 相似文献
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研究吐温-80协同酶法提取桑叶总黄酮。采用单因素实验和正交实验确定吐温-80协同酶法提取桑叶总黄酮的工艺,并与不加表面活性剂提取进行比较。结果表明吐温-80协同酶法提取工艺为吐温-80的质量浓度为1%,纤维素酶液125mL,温度为50℃,提取时间为1.5h,桑叶总黄酮的得率为2.467%,而同等条件下不加吐温-80的得率为1.718%。故吐温-80在酶法提取桑叶总黄酮中具有显著的增溶作用。 相似文献
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采用超声波技术辅助提取菠萝皮渣多糖,利用正交设计实验优化其提取工艺,并利用体外实验研究该多糖对羟自由基(·OH)、DPPH自由基(DPPH·)的清除能力及其还原能力,以评价其抗氧化活性。研究结果表明,超声波辅助提取最佳工艺参数为:料液比1∶50(m/v),时间40 min,温度60℃,功率为570 W,该条件下多糖的得率为2.38%;在本实验浓度范围(1.503.50 mg/m L)内,菠萝皮渣多糖对·OH的清除率随其浓度的增加而增加,但清除能力均低于同浓度VC,清除DPPH·自由基的IC50为2.47 mg/m L,对Fe3+的还原能力随多糖浓度的增加而增加。可见,超声波辅助提取工艺效果较好,能缩短提取时间,提高菠萝皮渣多糖的得率;体外抗氧化实验表明菠萝皮渣多糖具有一定的抗氧化活性。从菠萝皮渣中提取活性多糖,可以变废为宝,实现菠萝资源的高值化利用。 相似文献
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以新鲜皂荚叶为原料,采用超声波预处理-乙醇回流法提取皂荚叶多糖,利用正交设计实验研究乙醇浓度、料液比、回流时间和回流温度对皂荚叶多糖得率的影响,采用体外模型从清除DPPH自由基的能力、超氧阴离子(O2-·)活性和油脂抗氧化实验几个方面评价皂荚叶多糖的抗氧化活性,及在不同条件下的抗氧化稳定性。结果表明,皂荚叶多糖最佳提取工艺为乙醇浓度为100%,料液比为1:35 (g/mL),回流时间为100 min,回流温度为70 ℃。皂荚叶多糖提取液对 DPPH自由基的半抑制浓度(Ic50)为0.154 mg/mL,证明了皂荚叶多糖对于DPPH自由基具有良好的清除能力,对照实验证实皂荚叶多糖对于超氧阴离子(O2-·)具有一定清除能力,并对油脂也有一定的抗氧化活性。碱度、光照和金属离子Cu2+、Al3+对皂荚叶多糖抗氧化能力影响较大;金属离子Na+、K+影响较小。 相似文献
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桑叶多糖的提取及纯化实验研究 总被引:8,自引:0,他引:8
利用水煮醇沉法从桑叶中提取可溶性多糖,通过正交试验确定提取多糖的优化条件,用苯酚-硫酸法测定多糖含量,通过Seveg法除蛋白,粗多糖过葡聚糖凝胶(SephadexG-100)柱层析进行纯化分离,并用聚丙烯酰胺凝胶电泳进行纯度检查。研究结果表明,水浴温度100℃、桑叶∶水量=1∶100(w/v)、浸提60min、pH4为最佳提取条件,其多糖含量为98.52mg/g(DW)。柱层析纯化及聚丙烯酰胺凝胶电泳均表明桑叶多糖为单一多糖。 相似文献
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以桂花叶为原料,利用纤维素酶对桂花叶多糖进行提取,通过响应面设计优化最佳提取工艺,并对其抗氧化性进行研究。结果显示:液料比8∶1,酶解温度50℃,酶解时间60min,酶添加量1.2mg/m L时为桂花叶多糖最佳提取条件,得率达13.21%;桂花叶多糖清除DPPH·的能力与抗坏血酸效果近似,反映出桂花叶多糖具有较高的抗氧化活性。本研究通过对上述各种因素的优化,确定了桂花叶多糖的最佳提取条件及抗氧化性能,为桂花叶的深加工及利用提供参考依据和理论支持。 相似文献
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Eleftherios Alissandrakis Petros A. Tarantilis Christos Pappas Paschalis C. Harizanis Moschos Polissiou 《European Food Research and Technology》2009,229(3):365-373
The volatile fraction of unifloral Greek thyme honey was investigated by means of ultrasound-assisted extraction followed
by GC–MS analysis. Phenolic compounds were the most abundant, followed by short chain fatty acids. In total, 14 compounds
are proposed as potent botanical markers for thyme honey, 12 of which are phenolics. Among them, 3-hydroxy-4-phenyl-2-butanone
and 3-hydroxy-1-phenyl-2-butanone were the most important, as their concentration averages more than 35 mg/kg of honey. Significant
average proportions were found for 1-phenyl-2,3-butanedione, 3-hydroxy-4-phenyl-3-buten-2-one, 3,4,5-trimethoxybenzaldehyde
and 3,4,5-trimethoxybenzoic acid. Minor phenolics with statistical significance (p < 0.0001) are phenylacetonitrile, vanillin, 4-hydroxyphenylethanol, 4-hydroxyphenylacetonitrile, and 2-hydroxyacetophenone.
Phenylacetaldehyde, a common honey constituent is present at higher concentrations in thyme honey (p < 0.0001). Important non-phenolic components are 2-methylpropionic acid which was found at higher proportions in thyme honey
(p = 0.002) and 4-(4-hydroxy-2,2,6-trimethyl-7-oxabicyclo[4.1.0]hept-1-yl)-3-buten-2-one, a norisoprenoid found solely in this
type of honey. 相似文献
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红枣叶片叶绿素提取方法的比较 总被引:4,自引:0,他引:4
以骏枣叶片为试验材料,采用分光光度计比色法比较了3种提取溶剂和4种提取方法对骏枣叶片中叶绿素含量的影响,以期从中选出最佳提取方法。结果表明:同种浸提液不同提取方法时,研磨+室温静置提取和室温静置提取效果较好;同种提取方法不同浸提液时,乙醇浸提液提取效果要显著高于丙酮提取液浸提效果,提取液提取效果分别为:体积分数95%乙醇〉体积分数95%乙醇+体积分数80%丙酮〉体积分数80%丙酮。骏枣叶片叶绿素的提取采用95%乙醇研磨后黑暗中放置2h(其间不停搅拌)这一提取方法。 相似文献
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蓝莓叶多酚减压提取工艺优化 总被引:1,自引:0,他引:1
采用减压提取蓝莓叶多酚,在单因素基础上采用正交实验对pH、提取时间、料液比、粒度进行优化,得到最佳提取条件为:真空度-0.07MPa,乙醇浓度60%,pH3.5,提取时间60min,料液比1∶50,物料粒度80~100目,在此条件下多酚提取率为81.47%,多酚纯度为45.32%,其中多酚纯度比常压提取高6.57%。采用ORAC法、TEAC法、DPPH法、亚硝酸盐法对蓝莓叶多酚抗氧化能力进行评价,结果表明:蓝莓叶多酚有很强的抗氧化能力,减压提取的蓝莓叶多酚比常压提取的蓝莓叶多酚具有更强的抗氧化能力。 相似文献