麻叶千里光中生物碱的提取及测定分析

目的：以麻叶千里光为原料,采用索氏提取法、微波- 超声波协同提取法提取生物碱并测定其含量。方法：通过对索氏提取时间、提取温度、料液比;微波- 超声波协同提取时间、提取功率、料液比等单因素试验确定最佳单因素水平并做正交试验,确定以甲醇为提取剂提取麻叶千里光中生物碱类化合物的最佳工艺条件。然后采用紫外分光光度法和高效液相色谱法测定生物碱含量。结果：最佳提取工艺为：索氏提取时间5h,提取温度100℃,料液比1:30;微波提取时间180s,功率120W,料液比1:30。紫外分光光度法测定麻叶千里光中生物碱回收率为92.49%,精密度为3.15%;生物碱提取率索氏提取为0.05212%,微波- 超声波协同提取为0.03573%;高效液相色谱法测定麻叶千里光中生物碱回收率为89.60%,精密度3.75%;生物碱提取率索氏提取为0.04234%,微波超声波协同提取为0.02750%。结论：采用紫外分光光度法和高效液相色谱法测定麻叶千里光中生物碱含量,方法均较准确、可行。     

虫草素的微波- 超声波协同提取

研究蛹虫草菌丝体中虫草素的提取工艺及检测方法。确定微波- 超声波协同提取法为虫草素提取的最佳方法,依据单因素和正交试验获得最佳的提取工艺：乙醇体积分数70%、提取功率200W、提取时间110s、料液比1:240(g/mL)。此时虫草素含量达9.228mg/g。采用紫外分光光度法测定样品中虫草素含量,回收率为97.41%～99.60%,RSD 为1.469%,准确度和精密度都较高,是一种方便、成本较低的检测方法。     

响应面优化超声波-微波协同提取葡萄籽原花青素工艺研究

以衡水当地产葡萄籽为原料,利用超声波-微波协同提取葡萄籽原花青素。研究了乙醇体积分数、超声功率、超声时间、微波功率、微波时间、液料比对葡萄籽原花青素得率的影响。以单因素实验为基础,采用响应面法优化了超声波-微波协同提取葡萄籽原花青素工艺。结果表明,超声波-微波协同提取葡萄籽原花青素的最佳工艺条件为:乙醇体积分数50%,液料比21∶1,超声功率400 W,超声时间32 min,微波功率353 W,微波时间3.2 min。在最佳工艺条件下,原花青素得率为6.18%。     

正交试验法优化超声提取枣核总黄酮

目的：采用正交试验法,优选枣核中总黄酮的最佳超声提取工艺。方法：以芦丁为对照品,采用分光光度法进行测定,以提取液中黄酮含量作为考查指标,对影响黄酮提取工艺的因素进行了研究。首先,通过单因素试验研究了超声波功率、超声提取时间、料液比和提取溶剂乙醇体积分数对提取效果的影响,然后,利用正交试验法优化最佳提取工艺条件。结果：影响枣核黄酮提取的主要因素是乙醇体积分数与超声波功率,正交试验结果表明最佳提取工艺参数为：超声波作用功率是450W、超声波作用时间为30min、料液比1:50、乙醇体积分数50%。在此实验条件下,枣核黄酮粗品的提取率为7.04%,粗品中黄酮含量为1.59%。结论：采用正交试验-超声提取工艺,能有效提高枣核黄酮的提取效率,具有良好的应用前景。     

响应面法优化超声波提取山荆子抗氧化物质工艺

采用Box-Behnken响应面分析法研究超声波提取山荆子抗氧化物质的工艺条件。在单因素试验的基础上,研究乙醇体积分数、超声功率、提取时间对提取液抗氧化性的影响。建立该工艺的二次多项式模型。依据回归分析确定最优提取条件。结果表明:回归模型具有高度显著性。最佳提取工艺条件为乙醇体积分数57%,提取时间42min,超声功率为493W。此时提取液抗氧化性最强,亚铁还原能力(FRAP)值达最大值12 375.8。     

微波和超声波提取脐橙皮渣总黄酮工艺条件优化

采用单因素试验及均匀设计法试验和SPSS 13.0统计软件回归分析,进行微波辅助和超声波辅助提取赣南脐橙皮渣中总黄酮的工艺研究。结果表明：微波辅助最佳提取条件为功率390W、辐射时间7min、乙醇体积分数50%、料液比1:45(g/mL),总黄酮提取可达19.3mg/g;超声波最佳提取条件为温度70℃、超声提取时间60min、乙醇体积分数50%、料液比1:45(g/mL),总黄酮提取可达16.6mg/g。     

响应面法优化超声波提取安吉白茶抗氧化物质工艺

采用超声波法对安吉白茶抗氧化物质的提取工艺进行了研究。考察乙醇体积分数、超声功率、提取时间对提取液抗氧化性的影响。在单因素试验的基础上,采用3因素3水平的响应面分析法对安吉白茶抗氧化物质的提取工艺进行了优化,依据回归分析确定最优提取条件。试验结果表明,最佳提取工艺条件为:乙醇体积分数为51%,提取时间为51min,超声功率为480W。此时提取液抗氧化性最强,OD700nm为0.881。     

石榴皮多酚超声波-微波协同提取技术

探讨石榴皮加工副产品综合利用的基础因子。采用超声波-微波协同提取技术提取石榴皮中多酚类物质,研究了乙醇体积分数、料液比、微波功率、超声波功率、提取时间、浸提次数对石榴皮多酚提取得率的影响,并在单因素试验基础上进行正交试验,确定其较佳提取工艺为:以料液比1∶30 (g/mL)加入60%乙醇溶液浸泡20min后,在微波功率250W、超声波功率500W条件下提取1min,石榴皮多酚提取得率为(28.78±0.12)%,提高了提取效率。     

响应面法优化超声波-微波协同提取龙眼壳总黄酮

以龙眼壳为原料,研究了超声波-微波协同法对龙眼壳中总黄酮提取率的影响,并采用响应面分析法优化提取条件。结果表明,最佳提取条件为:超声波功率为100 W,液料比为29.2:1 mL/g,乙醇体积分数为50%,提取温度为57 ℃,提取时间5 min,在此条件下,龙眼壳总黄酮的提取率为3.06%,与超声或微波辅助提取法相比,该方法更省时,总黄酮提取率更高,适用于龙眼壳黄酮类物质的提取。     

微波与超声波提取杨梅汁多酚类物质的对比研究

以杨梅汁为原料,采用微波和超声波对杨梅汁中的多酚类物质提取进行了对比研究,两种方法分别采用单因素及正交实验,探讨了最佳提取条件和参数。结果表明:微波提取的最佳工艺参数为乙醇体积分数为80%,微波功率500 W,处理时间25 s,液料体积质量比为4 mL∶1 g;提取多酚提取量为514.837 mg/L;超声波提取的最佳工艺参数为乙醇体积分数为60%,超声波功率500 W,处理时间35 min,液料体积质量比为4 mL∶1 g,多酚提取量为609.256 mg/L。超声波提取的杨梅多酚类物质的量多于微波提取的量。     

返魂草总黄酮的微波提取及响应面优化

探讨返魂草中总黄酮的提取方法和工艺条件。以返魂草总黄酮提取率为考察指标,比较了热回流提取法、超声波提取法和微波提取法的提取效果,并通过单因素试验和响应面分析法优化其工艺条件。试验结果表明:微波法提取返魂草中总黄酮的最优工艺条件为:料液比1∶52(g/mL),提取温度87℃,提取时间3.1 min,在此条件下总黄酮的提取率为4.827%。研究得到的工艺条件可用于返魂草总黄酮的提取。     

超声辅助提取瑭溪蜜柚皮中酚酸的研究

利用20kHz的超声波辅助提取琯溪蜜柚皮中的酚酸,主要研究了超声参数(超声时间、温度、超声功率)对琯溪蜜柚皮中的7种酚酸(咖啡酸、对香豆酸、阿魏酸、芥子酸、原儿茶酸、对羟基苯甲酸、香草酸)和黄酮糖苷(柚皮苷)的影响。结果表明:柚皮苷和酚酸的含量都随着超声时间和温度的增加而增加。超声功率对柚皮苷含量的影响较小,但对7种酚酸有不同程度的影响。确定了超声提取琯溪蜜柚皮中柚皮苷和酚酸的最佳提取条件:柚皮苷,超声30 min、超声温度40℃、超声功率8 W;酚酸,超声30 min、超声温度30℃、超声功率30 W。     

笋壳多糖的微波-超声波联合辅助提取工艺优化及其抗氧化活性

目的：通过微波-超声波联合辅助提取法优化笋壳多糖提取工艺,并研究其抗氧化活性。方法：考察提取时间、料液比、微波功率、超声波功率、提取次数对笋壳多糖含量的影响,在单因素试验基础上做L9（34）正交试验优化提取工艺参数,通过测定笋壳多糖清除羟自由基、超氧阴离子自由基、1,1-二苯基-2-苦基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基的能力来评价其抗氧化活性,并同传统热水浸提法进行比较。结果：微波-超声波联合辅助提取最优工艺条件为提取时间30 min、料液比1∶30（g/mL）、微波功率200 W、超声波功率750 W,笋壳多糖得率为2.76%,粗多糖中多糖含量为37.63%;清除羟自由基、DPPH自由基和超氧阴离子自由基的半抑制浓度分别为0.17、0.43 mg/mL和大于16 mg/mL。微波-超声波联合辅助提取法的各项指标均优于热水浸提法。结论：微波-超声波联合辅助提取笋壳多糖比传统热水浸提具有耗时短、效率高等优点,笋壳水溶性多糖具有显著体外抗氧化活性。     

响应面法优化笋头多糖微波-超声波辅助提取工艺

本文以福建毛竹笋笋头为原材料,在单因素实验的基础上,结合响应面分析法对微波-超声波联合辅助传统水提笋头多糖的工艺参数进行优化。结果表明,微波-超声波联合辅助传统水提笋头多糖的最优工艺参数为料液比1:30 g/mL、水浴温度95℃、水浴时间2.0 h、超声波功率600 W、微波功率300 W、微波-超声波时间3.0 min。在此条件下笋头多糖得率为10.05%,对比传统热水浸提法笋头多糖得率提高了32.06%。经检测,笋头多糖的总糖、蛋白质和糖醛酸含量分别为74.87%、4.05%和1.89%。该方法能显著提高笋头多糖得率,可为竹笋的综合利用和笋多糖产品的进一步开发提供一定参考。     

Optimisation of the microwave‐assisted extraction process for six phenolic compounds in Agaricus blazei murrill

An efficient microwave‐assisted extraction (MAE) technique was employed in the extraction of phenolic compounds from Agaricus blazei murrill, and phenolic compounds were quantified by High‐performance liquid chromatography (HPLC). The MAE procedure was optimised, validated and compared with other conventional extraction techniques. MAE gave the best result because of the highest extraction efficiency within the shortest extraction time. The optimal conditions of MAE were 60% ethanol, ratio of solid/liquid 1:30, temperature 110 °C, irradiation power 500 W and three extraction cycles, each 5 min. This is the first report on combining MAE with HPLC for the extraction and quantification of phenolic compounds in A. blazei murrill. The developed MAE method provided a good alternative for the extraction of phenolic compounds in A. blazei murrill as well as other materials.     

The effect of microwave assisted extraction on the isolation of anthocyanins and phenolic acids from sour cherry Marasca (Prunus cerasus var. Marasca)

The aim of this study was to evaluate the influence of microwave assisted extraction on the isolation of anthocyanins and phenolic acids from sour cherry Marasca. A general factorial design was used to study the effect of temperature (from 50 to 70 °C), irradiation time (5–12 min) and microwave power (350–500 W) on individual, total anthocyanins and individual and total phenolic acids. Optimal microwave assisted extraction conditions differed for anthocyanins and phenolic acids, especially in terms of temperature and irradiation time, so lower temperature (60 °C) and shorter time (6–9 min) was more convenient for anthocyanins extraction, while phenolic acids gave higher extraction yield at higher temperatures (70 °C) and longer irradiation time (10 min). The optimal microwave power did not differ significantly for studied compounds, ranging about 400 W. Compared to conventional extraction, microwave assisted one showed higher efficiency for all studied compounds.     

ULTRASONICALLY ASSISTED EXTRACTION OF PHENOLIC COMPOUNDS FROM AROMATIC PLANTS: COMPARISON WITH CONVENTIONAL EXTRACTION TECHNICS

Extracts of aromatic plants contain bioactive substances such as phenolic compounds, which could be used as natural antioxidants. Conventional, as well as ultrasonically assisted extractions (UAEs ) of phenolic compounds from aromatic plants using different solvents, have been studied. Reversed phase high performance liquid chromatography (RP‐HPLC ) with ultraviolet detection was employed for the analysis of phenolic compounds. Total phenolic compounds were determined by the Folin–Ciocalteu assay. The amount of extractable phenolic substances for this method decreased with decreasing polarity of the solvent in the order water, 60% methanol, 60% acetone, and ethyl acetate/water (60:30, v/v). The HPLC results indicate that UAE is a more effective technic compared to the conventional method but was dependent on the solvent and the temperature employed. Increasing the temperature of sonication, the efficiency of extraction of phenolic compounds for all solvents is enhanced. However, water extraction was found to give reduced amounts of phenolic compounds when compared with the conventional method.     

Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste

The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.     

Assisted extraction of rosemary antioxidants with green solvents

The use of natural antioxidants in the food industry has increased in the last years and there is a growing interest in improving the extraction processes using GRAS (general recognize as safe) solvents. In this work the extraction of antioxidants from rosemary with ethanol and water as solvents has been studied using different extraction processes (conventional, microwave assisted - MAE - and ultrasound assisted - USAE -) and plant pretreatments (deoiled and milled, deoiled and fresh plant). Total phenolic compounds in the extracts were determined by the Folin-Ciocalteu assay and HPLC with UV detection was employed for the quantitation of the main antioxidant compounds: rosmarinic acid and carnosic acid. The antioxidant activity of the extract was determined by the DPPH scavenging assay. The double pretreatment, deoiling by solvent free microwave extraction (SFME) and milling, has shown to be essential to overcome inner mass transfer limitations. Extraction efficiency can be additionally enhanced by microwave and ultrasound assisted extraction process, being this latter more significant in aqueous extracts.