Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis

With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.

Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds

Naturally occurring camptothecin（CPT） is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present study,ultrasound-assisted extractions（UAE） of CPT from C.acuminata seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid Chromatography.The conditions of alkaline species and concentrations,extraction time,extraction temperature and ultrasonic power were optimized.Results show that both Na3PO4 and Na2CO3 solutions gain good extraction yields,whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does,thus aqueous Na2CO3 is more beneficial for the extraction.The optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50°C and ultrasonic power of 400 W for 60 min.Comparing with UAE with ethanol,the extraction with 0.5% Na2CO3 solution achieves higher yield.Moreover,aqueous Na2CO3 as a solvent has various advantages including non-toxicity,inflammable,non-corrosive and low cost,which ensure this UAE method is a superior method with high utilizing prospect.

Ionic Liquid-Based Ultrasound-Assisted Emulsification Microextraction Coupled with HPLC for Simultaneous Determination of Glucocorticoids and Sex Hormones in Cosmetics

An effective and environmentally friendly method based on ionic liquid-based ultrasound-assisted emulsification microextraction(IL-USAEME) and high performance liquid chromatography (HPLC) has been developed for the determination of nine hormones including three glucocorticoids, one androgen and five progestogens in cosmetics. Several factors that affect the extraction efficiency, such as the kinds and volume of ionic liquid, salt concentration, ultrasonic power and time, and centrifugation time were investigated and optimized. Under the optimum extraction condition, the recoveries of analytes ranged from 85.97% to 108.84% except prednisolone (62.30%). The intraday and interday precision was below 2.51% and 3.30%, respectively.

Analysis of anticancer compound,indole-3-carbinol,in broccoli using a new ultrasound-assisted dispersive-filter extraction method based on poly(deep eutectic solvent)-graphene oxide nanocomposite

Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature.In this study,a rapid,accurate,and lowcost ultrasound-assisted dispersive-filter extraction(UADFE)technique based on poly(deep eutectic solvent)-graphene oxide(PDES-GO)adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time.PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption.UADFE was developed by combining dispersive solid-phase extraction(DSPE)and filter solid-phase extraction(FSPE)to realize rapid extraction and separation.Based on the above two strategies,the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography(HPLC)allowed the rapid(15-16 min),accurate(84.3%-96.4%),and low-cost(adsorbent:3.00 mg)analysis of I3C in broccoli and was superior to solid-phase extraction,DSPE,and FSPE methods.The proposed method showed remarkable linearity(r=0.9998;range:0.0840-48.0 mg/g),low limit of quantification(0.0840 mg/g),and high precision(relative standard deviation<5.6%).Therefore,the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples.

Effect of Ultrasound-Assisted Extraction of Phenolic Compounds on the Characteristics of Walnut Shells

Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially good natural sources of antioxidants for the food and pharmaceutical industries. In this study, phenolic compounds were extracted using an ultrasonic bath, an ultrasonic probe and a standard shaking method. The extraction yield achieved with an ultrasonic probe was 51.2 mg GAE/g DW, two times higher than both the shaking method and the ultrasonic bath method which were 20.6 mg GAE/g DW and 25.8 mg GAE/g DW, respectively. Phenolic extraction was further improved by a size reduction of the walnut shells. The best extraction yield of 52.8 mg GAE/g DW was attained when the particle size was between 45 - 100 mesh. The ultrasonic probe treatment is the best method for extraction of phenolic compounds from walnut shells. Scanning electron microscopy (SEM) imaging indicated that the ultrasonic probe treatment could better rupture the hard structure of the cells, increasing the penetration of solvents and thus the extraction yield.

Ultrasound-Assisted Emulsification Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Separation of Trace Gold Prior to Flame Atomic Absorption Spectroscopy Determination

In the present work, a ultrasound-assisted emulsification dispersive liquid-liquid microextraction based on solidification of floating organic droplet method has been developed as a sample preparation method prior to flame atomic absorption spectrometry determination of trace amounts of gold in the standard, wastewater and river water samples. In the proposed method, 1-dodecanol and 5-(4-dimethylamino-benzylidene) were used as extraction solvent and chelating agent, respectively. Several factors that may be affected on the ex-traction process, such as type and volume of the extraction solvent, ionic strength, pH of the aqueous solu-tion, extraction temperature and extraction time were studied and optimized. Under the best experimental conditions, the calibration curve exhibited linearity over the range of 8.0 ng●mL-1- 3.0 μg●mL-1 with a correlation coefficient of 0.9978 and detection limit based on three times the standard deviation of the blank signal was 1.5 ng●mL-1. Eight replicate determinations of 0.2 and 1.0 μg●mL-1 of gold gave a mean absorbance of 0.051 and 0.253 with relative standard deviations of ±2.3% and ±1.5%, respectively. Finally, the developed method was successfully applied to the extraction and determination of gold ions in a silica ore, wastewater, river water and standard samples and satisfactory results were obtained.

Pectinmethylesterase extraction from orange solid wastes: Optimization and comparison between conventional and ultrasound-assisted treatments

During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is their treatment by addition of lime and a latter pressing, obtaining a press cake and a press liquor rich in sugars (10&#176;Brix) and citric acid, protein, pectin and ethanol. For non-thermal concentration of press liquor to obtain citruss molasses (65&#176;-70&#176;Brix), the removal of pectin is necessary. Traditionally, depectinization of juices has been done by using pectinmethylesterase (PME) enzymes from external sources. In this work it performed the extraction of PME enzymes from orange peels to obtain the optimum extraction conditions. Two different methods of solventextraction were compared (conventional andultrasound-assisted methods). For the conventional extraction experiments, a central composite design with three variables ([NaCl], pH and time) and five replicates of the center point was used. For ultrasound-assisted extraction, experiments were done at pH = 5.5 and [NaCl] = 1.25M), varying extraction time (1-30 min). Response variables were PME activity, protein content and a ratio between them, named PME effectiveness (ηPME). At the same experimental conditions (pH =5.5, [NaCl] = 1.25 M, t = 15 min) it was found that conventional extractions led to slightly better results in terms of ηPME than ultrasound-assisted extraction method.

双水相协同超声法提取枇杷叶中绿原酸的工艺研究

试验采用响应面法优化双水相协同超声法提取枇杷叶中绿原酸的工艺,探讨提取液中乙醇体积分数、超声温度、超声时间、磷酸氢二钾用量和超声功率对绿原酸提取率的影响。结果显示,双水相协同超声法提取枇杷叶中绿原酸最佳提取工艺条件为乙醇体积分数61%、超声温度61℃、超声时间25 min、磷酸氢二钾用量4.6 g,此条件下绿原酸提取率1.53%,与预测值相接近。研究表明,双水相协同超声法提取枇杷叶中绿原酸的提取工艺稳定可行,可为枇杷叶的资源化开发与利用提供参考。

水产品超声辅助浸渍冷冻技术研究进展

目的为延长水产品销售周期,最大程度保持其营养品质,促进水产品冷冻保藏及加工技术的发展和产业化。方法归纳总结超声辅助浸渍冷冻的作用机理,并探究其对冰晶形成和生长以及水产品保鲜加工的影响。结果超声辅助浸渍冷冻能有效提高冷冻效率,减小冰晶晶核规格,缩短冷冻时间,减缓水产品蛋白质变性与脂质氧化速率,改善水产品质构、保持其营养价值,是水产品冷冻处理的有效途径。结论超声辅助浸渍冷冻技术能在一定程度上解决水产品冷冻过程中存在的问题,为水产品冷冻技术产业化提供支持。超声辅助浸渍冷冻技术在作用机制、适用范围和特定环境下的作用衰减等方面存在着一定缺陷,还需深入阐述其作用机理,为冷冻智能装备开发提供保障。

超声辅助酶法提取玉米胚芽粕水解蛋白及其抗氧化活性

以玉米胚芽粕为原料,研究超声波辅助碱性蛋白酶提取玉米胚芽粕水解蛋白的工艺条件。通过单因素试验初步确定超声波辅助酶法提取玉米胚芽粕水解蛋白的条件,在单因素试验基础上进行正交试验设计,并测定其抗氧化活性。结果表明,最优提取条件为超声温度50℃、超声时间50 min、超声功率140 W,在此条件下,玉米胚芽粕的水解蛋白提取率为90.6%。对DPPH自由基和羟自由基的IC_(50)分别为17.56µg/mL和28.41µg/mL。

正交试验法优化紫苏叶中总黄酮提取工艺及体外抗氧化活性研究

试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率影响的主次顺序为:提取温度>乙醇浓度>液料比>提取时间。紫苏叶总黄酮最优提取工艺参数为乙醇浓度50%、液料比20 mL/g、提取温度70℃和提取时间45 min。在此条件下,紫苏叶总黄酮得率为4.05%。紫苏叶总黄酮对DPPH自由基与羟自由基具有较强的清除作用,其IC50值分别为160 mg/L和196 mg/L。研究表明,紫苏叶总黄酮具有较强的抗氧化性能,是一种优质的天然抗氧化物质。

超声辅助浸渍处理对冻干柠檬片品质的影响

采用超声辅助浸渍处理对柠檬片进行预处理,探究不同质量分数护色剂及超声辅助浸渍处理对冻干柠檬片色泽、营养物质与风味品质的影响。结果表明:最佳护色剂配方为普鲁兰多糖质量分数0.9%、乙二胺四乙酸二钠质量分数0.2%、CaCl_(2)质量分数0.1%、柠檬酸质量分数1.0%,最佳超声处理时间为10 min。与未超声处理组相比,超声处理10 min的冻干柠檬片亮度、复水比、维生素C含量、抗氧化成分及抗氧化能力总体提高。

超声波-微波辅助酶法提取花生红衣白藜芦醇的工艺研究

以花生红衣为原料,以白藜芦醇得率为研究指标,采用超声波-微波辅助酶法提取技术,在单因素试验的基础上,采用响应面法对花生红衣白藜芦醇的提取工艺进行优化,得到最佳工艺条件为:酶添加量2.00%,超声波功率260 W,协同时间20 min,微波功率200 W,此工艺条件下花生红衣白藜芦醇得率为0.998 mg/100 g。研究结果为花生红衣的废物利用和工业化生产提供了理论依据及数据支撑。

超声辅助酶法制备富锌低分子牡蛎肽的工艺研究

以香港牡蛎为原料,通过酶解法制备富锌牡蛎酶解产物并对其相对分子量图谱和氨基酸组成进行分析。经过蛋白酶筛选、超声预处理后应用单因素试验、正交试验以及时间曲线优化酶解工艺,提高酶解产物的水解度和生物锌释放量。采用超声功率500 W、超声时间10 min进行预处理,选择动物蛋白酶进行酶解。最佳酶解工艺为加酶量1.6%、酶解时间4 h、酶解温度50℃、料液比1∶4、pH 6.5,得到牡蛎酶解产物水解度为49.581%。酶解产物的锌含量(以干基计)为680.831 mg/kg。牡蛎肽相对分子量小于1000 Da的组分达到81.87%,富含酸性氨基酸谷氨酸和天冬氨酸。香港牡蛎酶解产物中含有丰富的小分子肽,氨基酸组成较完善,锌含量较高,可为后续富锌产品的开发奠定基础。

超声协同蒸汽处理对壳鸡蛋表面大肠杆菌的杀菌机理及动力学分析

为了探究超声蒸汽协同处理对蛋壳表面大肠杆菌的预测杀菌效果以及细菌损伤和死亡的机制,本研究以大肠杆菌为研究对象,构建了超声蒸汽协同处理对蛋壳表面大肠杆菌的杀菌动力学模型。通过控制蛋壳表面细菌液的浓度,讨论超声、蒸汽和超声与蒸汽协同作用对大肠杆菌的灭活作用,并与商业化杀菌中常用的次氯酸钠浸泡法进行比较。采用线性模型、Weibull模型、Log-Logistic模型和Modified Gompertz模型拟合了超声辅助蒸汽处理大肠杆菌的灭活曲线,对灭菌前后细胞形态的破坏程度和细胞内容物的泄漏情况进行分析。结果表明,经过180 s的150 W超声预处理和3 s的蒸汽处理后,大肠杆菌总数的对数值从6.26下降到2.04,死亡率达到67%。超声辅助蒸汽处理的灭菌过程更符合非线性动力学模型,且随着超声强度的增加和蒸汽处理时间的延长,Weibull模型更适合描述灭菌的动态过程。此外,协同处理会破坏大肠杆菌的超微结构以及菌体细胞的外部结构,使菌体细胞质溢出,从而改变膜的通透性。因此,超声协同蒸汽处理会加剧细菌的变形和损伤,导致细菌死亡。实验结果可为蛋壳表面大肠杆菌的灭活提供理论依据,综合贮藏期鸡蛋品质分析结果,该方法在禽蛋洁蛋生产中具有一定的应用前景。

超声辅助不同小分子糖渗透处理后真空冷冻干燥油柑的品质比较

该研究评价了超声辅助五种小分子糖渗透处理后冻干油柑的理化特性及体外抗氧化活性。结果表明:相比对照组,经超声辅助渗糖处理的油柑水分损失率、固形物增加率升高;冻干油柑内部孔隙更加致密,硬度显著提高、脆度基本保持,复水性下降;低聚异麦芽糖处理组的吸湿率(18.25%)低于对照组(22.54%);葡萄糖和麦芽糖处理组的冻干油柑色差ΔE小,分别为2.73和1.71,即颜色保留率高;低聚麦芽糖和蔗糖对冻干油柑的风味强化效果较好;蔗糖、葡萄糖和麦芽糖处理组的冻干油柑可滴定酸含量较低;与对照组玻璃化转变温度(T_(g)=43.66℃)相比,麦芽糖处理组的T_(g)升高到45.53℃,其他处理组则显著降低了样品的T_(g);除木糖醇处理组(9.44 mg/g)外,不同超声渗糖处理组的总酚保留率均较高;蔗糖和低聚异麦芽糖渗透处理可有效保持冻干油柑的体外抗氧化能力。总的来说,超声辅助蔗糖和低异聚麦芽糖渗透处理的冻干油柑品质较好,其中低异聚麦芽糖可作为一种蔗糖替代品用于开发功能性冻干油柑。

超声辅助复合酶法提取板栗仁中可溶性膳食纤维工艺优化及其结构表征

以燕山板栗为原料,采用超声辅助复合酶法提取板栗膳食纤维。通过单因素试验考察复合酶(m(α-淀粉酶)∶m(糖化酶)=4∶1)添加量、中性蛋白酶添加量和超声波处理时间对板栗膳食纤维得率的影响,设计响应面试验对酶解工艺中各影响因素进行优化,并采用扫描电镜、红外光谱和热质量分析对其结构进行表征。结果表明,以板栗的质量计量,超声辅助复合酶法提取膳食纤维最佳条件为:复合酶添加量为11%,中性蛋白酶添加量为4%,超声波处理时间15 min。在此条件下,板栗膳食纤维得率为22.22%。扫描电镜显示板栗膳食纤维呈现松散的片状或层状结构,表面具有较多的孔洞。红外光谱显示其具有膳食纤维的特征吸收峰。热质量分析板栗膳食纤维适合在400℃以下温度加工。超声辅助复合酶法能有效用于板栗中膳食纤维的提取。

响应面法优化超声波辅助提取公英散工艺参数及其抑菌和抗氧化性能研究

本试验旨在通过响应面法优化超声波辅助提取公英散工艺参数,并对公英散水提物的体外抗氧化和抑菌活性进行测定。通过单因素试验确定各因素的取值范围,用Plackett-Burman设计并筛选出超声温度、超声时间、液料比3个显著影响公英散提取效率的因素,然后采用Box-Behnken响应面分析法得出最佳提取条件。通过微量肉汤稀释法和Kirby-Bauer纸片扩散法评价公英散水提物体外抑菌活性,采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法和羟自由基清除法研究公英散水提物体外抗氧化活性。结果表明:在超声波功率420 W、超声温度80℃、超声时间65 min、液料比37∶1时,公英散的提取效率最高。公英散水提物对3种奶牛乳房炎临床致病菌都有不同程度的体外抑制作用,对大肠杆菌(E.coli)的最低抑菌浓度(MIC)为9.00 mg/mL,最低杀菌浓度(MBC)为18.00 mg/mL;对无乳链球菌(S.agalactiae)的MIC为4.50 mg/mL,MBC为9.00 mg/mL;对金黄色葡萄球菌(S.aureus)的MIC为2.25 mg/mL,MBC为4.50 mg/mL。此外,当公英散水提物浓度达到1.00 mg/mL时,对羟自由基(78.70%)和DPPH自由基体外清除率(75.63%)良好。综上所述,本试验成功筛选出了公英散的最佳提取工艺条件,且所得公英散水提物有良好的体外抗氧化活性,并对3种奶牛乳房炎临床致病菌均有不同程度的体外抑菌活性。

超声辅助深共晶溶剂高效提取枳实辛弗林的工艺优化及提取动力学分析

为了研究超声辅助深共晶溶剂提取枳实辛弗林的最佳工艺条件及该提取过程的传质动力学模型,本研究采用Plackett-Burman试验、最陡爬坡试验结合Box-Behnken响应面法对超声辅助深共晶溶剂提取枳实辛弗林的关键工艺参数进行优化,基于Fick第二定律建立超声辅助深共晶溶剂提取枳实辛弗林的提取动力学模型,通过测定在不同功率、不同提取时间下提取液中的辛弗林的质量浓度,对模型进行拟合验证,求解相应的动力学参数。结果表明,最优提取溶媒为一水甜菜碱-乳酸组成的深共晶溶剂(摩尔比1∶3,含水量50%),最佳工艺为:液料比39 mL/g,超声功率220 W,超声时间20 min,在此条件下,辛弗林得率为0.4284%,与模型预测值接近,且优于传统水回流提取法、85%乙醇回流提取法、超声辅助14%乙醇提取法、超声辅助70%甲醇提取法和超声辅助水提法。对动力学实验数据拟合得到的动力学一般方程和指数方程与动力学模型相关性良好,推算出了相应的速率常数、相对萃余率等动力学相关参数,拟合得到了半衰期和有效扩散系数回归方程,为枳实辛弗林的提取工艺优化和深入理论研究提供数据参考。

Ultrasound-assisted Low Density Solvent Based Dispersive Liquid-liquid Microextraction for Determination of Phthalate Esters in Bottled Water Samples

A technique of ultrasound-assisted low density solvent based dispersive liquid-liquid microextraction was developed for the determination of four phthalate esters, including dimethyl phthalate（DMP）, diethyl phthalate（DEP）, di-n-butyl phthalate（DnBP） and di（2-ethylhexyl） phthalate（DEHP） in bottled water samples. A low density solvent, toluene, was selected as extraction solvent. In the extraction process, a mixture of 15 μL of toluene（extraction solvent） and 100 μL of methanol（disperser solvent） was rapidly injected into 1.0 mL of water samples. A cloudy solution was formed after ultrasounded for 5 min, and then centrifuged at 5000 r/min for 5 min. The enriched analytes in the floa- ting phase were determined by means of gas chromatograph. Under the optimum conditions, the enrichment factors were found to be in a range of 29--67, and the recoveries were ranged from 81.2% to 103.9%. The limits of the detection were in a range of 3.8--5.6 μg/L. The proposed method was applied to the extraction and determination of phthalate esters in bottled water samples, and the concentrations of phthalate esters found in the water samples were below the allowable levels.