Profiling the effects of microwave-assisted and soxhlet extraction techniques on the physicochemical attributes of Moringa oleifera seed oil and proteins

There is a constant search for biomaterials from natural products like plants for food and industrial applications.The work embodied in this report aimed at investigating the effects of microwave-assisted and soxhlet extraction(MAE and SE) techniques on the functional physicochemical quality characteristics of Moringa oleifera seed oil and proteins extracts. M. oleifera seeds were ground to fine powders and oil was extracted by microwave-assisted and soxhlet extraction techniques using petroleum ether. Quality attributes including yield percent, moisture content,iodine, saponification, specific gravity, viscosity, p H, thiobarbituric acid, acid and peroxide values were measured. Mineral and vitamin contents, chemical/functional groups, fatty acid(FA) composition, and reducing power of the oil were evaluated. Metabolomics of protein extracted from the defatted powders were analyzed by nuclear magnetic resonance(NMR). M. oleifera oil from MAE and SE methods had good yield(34.25 ± 0.0%,28.75 ± 0.0%), low moisture content(0.008 ± 0.0%, 0.011 ± 0.0%), non-drying and unsaturated, moderately saponified, less dense(0.91 ± 0.01, 0.92 ± 0.02 g m L^(-1)), had Newtonian flow, were weakly acidic, showed good content of FAs, recorded strong potential for long shelf-life, showed stability against oxidative rancidity and enzymatic hydrolysis, had very rich deposits of micro-and macro-nutrients as well as water-soluble and lipidsoluble vitamins, and functional groups in the oil were reflective of its content of long-and medium-chain triglycerides(LCT and MCT). Monounsaturated and saturated fatty acids(MUFA and SFA) were detected and the oil has excellent ferric ion reducing power. NMR metabolomic assay revealed the presence of nine essential amino acids(EAAs) in the protein extract. MAE technique is a feasible and acceptable alternative for high throughput extraction of M. oleifera oil with high yield and excellent quality attributes. The study revealed that MAE did not impart any remarkable advantage(s) on the physicochemical properties of M. oleifera seed oil and protein compared to SE technique.

Discoursing on Soxhlet extraction of ginseng using association analysis and scanning electron microscopy

Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In this study, Panax ginseng was selected as a model sample. Soxhlet extraction by means of a water bath, which has always been neglected, was identified as a novel key factor in the poor repeat- ability in different batches of Soxhlet extraction, as it can affect the siphon times and reflux time, which have been positively correlated with the ginsenoside contents. By substituting round bottom flasks in the same column, the relative standard deviation of the most fluctuated compound, ginsenoside Rbl, was decreased from 24.6% to 5.02%. Scanning electron microscopy analysis confirmed that the breakdown of the surface of the ginseng powder in the Soxhlet extraction led to a better dissolution of ginsenosides, indicating that chloroform may promote the extraction of ginsenosides by disrupting the cell structure. Moreover, 70% methanol was regarded as the better solvent for extracting the ginsenosides. Overall, this work offers a practical and effective protocol for improving the accuracy and repeatability of Soxhlet extraction methodology for ginsenosides and other analytes.

Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques

The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented.

Phytochemicals Screening, Phenolic Estimation and Evaluation for Anti-Oxidant, Anti-Inflammatory and Anti-Microbial Activities of Sequentially Soxhlet Extracted Coconut Testa

Background: In many coconut industries, the outer layer of thin brown skin of coconut kernel known as testa is peeled out as a byproduct. Despite the testa is rich in fat and plenty of polyphenolic compounds, it has been underutilized either as animal feed, serving as raw materials for bio-diesel production or discarded directly. Anticipating coconut testa (CT) as a natural source of multiple phyto-chemicals, its exploitation for the pharmacological activity or utilization as value added product is required which may reduce the disposal costs as well. Methods: Secondary metabolites from CT were extracted sequentially with different organic solvents based on polarity in the soxhlet apparatus followed by extraction with sterilized water. The crude dried extracts thus prepared were evaluated for qualitative screening of phytochemicals and quantitative estimation of total phenols, flavonoids and tannin content. Moreover, the antioxidant, anti-inflammatory and anti-microbial activities were also investigated. Results: Phytochemicals screening revealed the presence of polyphenolic compounds in methanolic fraction including phenols (822.60 ± 16.36 mg/g), flavonoids (103.30 ± 9.78 mg/g) and tannin (663.50 ± 19.26 mg/g), whereas non-phenolic compounds were present in other fractions. While methanolic fraction showed invariably the highest anti-oxidant activity in multiple assay methods, non-phenolic compounds in aqueous and chloroform fractions exhibited high anti-inflammatory activity. Antimicrobial activity was observed by both phenolic and non-phenolic compounds. Conclusion: The findings of the study reveal that CT is a rich source of various polyphenolic and non-phenolic natural antioxidants, anti-inflammatory and antimicrobial compounds. These findings are promising and form the basis to identify the number of active components and their characterization.

蚕丝含油率微波萃取试验方法探讨

针对目前蚕丝含油率检测效率低、耗时长、资源浪费大的问题,选用微波萃取工艺,设计4因素3水平的正交试验,分析比较微波萃取法与索式萃取法在蚕丝含油率检测方面的应用,探讨微波萃取法的测试条件。试验结果表明:微波萃取法相比索式萃取法检测准确度更高,过程更环保,且检测时间和试剂用量更少;微波萃取温度、萃取时间、萃取功率及乙酸乙酯用量各因素对样品含油率测试结果的影响从大到小依次为萃取温度、乙酸乙酯用量、萃取时间和萃取功率。最优检测条件为:萃取温度67℃,乙酸乙酯用量40 mL,萃取时间15 min,萃取功率800 W。

4种柑橘籽油脂肪酸组成及生物活性成分

以瓯柑籽、椪柑籽、香橙籽、胡柚籽为原材料,通过索氏提取法提取油脂,利用气相色谱和高效液相色谱分别对4种油脂样品的脂肪酸以及主要的柠檬苦素类化合物、类黄酮类化合物含量进行测定分析。结果表明,4种柑橘籽油的脂肪酸主要由油酸(19.7%~49.0%)、亚油酸(17.93%~45.93%)、棕榈酸(23.04%~27.73%)以及少量的亚麻酸(1.327%~5.103%)和硬脂酸(3.437%~4.797%)组成。生物活性成分柠檬苦素、诺米林、奥巴叩酮、橙皮苷、柚皮苷含量分别为24.79~753.75、266.57~915.62、61.95~496.08、15.61~17.57、27.84~30.01μg/g。柑橘籽油不仅脂肪酸比例合理,还含有较丰富的黄酮及柠檬苦素类化合物,作为植物油原料具有开发潜力。

不同分离方法分离烃源岩可溶有机质的对比实验

对加速溶剂萃取与索式提取两种烃源岩可溶有机质分离方法的分离总量、分离效率、可溶有机质的化学与分子组成进行了对比。结果表明:加速溶剂萃取分离出的可溶有机质总量略低于索式提取,但分离效率远高于索式提取;加速溶剂萃取所得的可溶有机质中饱和烃与芳香烃的相对百分含量高于索式提取,非烃与沥青质的相对百分含量低于索式提取;两种分离方法所得的可溶有机质中高碳数饱和烃与芳香烃化合物的分布形态、地球化学比值参数和绝对含量均具有很好的可比性,相反,二环倍半萜系列化合物显示较大差异,加速溶剂萃取所得可溶有机质的低碳数、低沸点的二环倍半萜化合物的相对百分含量高于索式提取。

循环周转型临时看台支承架体重复对比试验研究

为积极响应国家走绿色可持续发展道路的号召,北京冬奥会采用了大量支承架体用于临时看台或舞台的搭建。为研究赛后的临时看台支承架体能否安全合理地被再次使用,以索氏不锈钢插销式节点临时看台支承架体为研究对象,设计并制作了一个横纵均为2跨且跨度为2 m的足尺模型试件,共进行了两次试验,即在首次水平加载试验结束后,将该试验架体搭建在室外,经历长时间严寒风雪后再重复做一次试验,重点对比分析了其在4种不同恒载与水平荷载组合作用下的整体结构变形模式、力学性能及典型位置峰值应变等。研究结果表明:在恒载为0.0 kN∙m^(-2)、0.5 kN∙m^(-2)、2.0 kN∙m^(-2)和3.5 kN∙m^(-2)的工况下,两次试验中架体结构的试验现象及变形模式基本相同,力学性能差值在5%以内,典型位置处峰值应变差值在10%以内,累计损伤较小。两次试验结束后结构均未出现明显损伤,仍具有较大安全储备,所以在经历长时间的严寒风雪后,临时看台支承架体仍可以被重复使用。研究结果可为北京冬奥会临时设施架体的赛后利用等研究提供参考。

索氏抽提法制备裂果枣红色素及其理化性质分析

以裂果枣粉为原料,采用索氏抽提法对裂果枣红色素进行提取,分别采用单因素试验和响应面试验进行提取条件的优化,并对裂果红枣色素进行理化性质研究(抗氧化活性及色素稳定性)。结果表明:索氏抽提法提取最佳条件为裂果枣粉添加量2.0 g/100 mL、乙醇体积分数69%、加热温度89℃、浸提时间26 min、抽提时间1.5 h,裂果枣红色素提取率4.540 mg/g,裂果枣红色素提取率较高。通过研究裂果枣红色素对DPPH自由基,·NO_(2)^(-)和ABTS+自由基的清除能力,结果显示裂果枣红色素浓度达到1.2 mg/mL时,DPPH自由基清除率可达67.8%,当裂果枣红色素浓度达到2.0 mg/mL时,NO_(2)^(-)清除率为69.4%,当裂果枣红色素浓度达到1.5 mg/mL时,ABTS^(+)自由基清除率达到63.5%。裂果枣红色素稳定性试验结果表明,索氏抽提法提取的裂果枣红色素具有良好的热稳定性,光照对其稳定性有一定的影响,pH值对裂果枣红色素稳定性的影响较大。

油茶籽功能性成分的提取、鉴定及其活性评价

油茶籽广泛种植于我国南方地区,是食用植物油的重要原料。为了探明其有效成分,文章首先通过气相色谱-质谱法对其挥发性成分进行分析。其中,顺-十八碳烯酸、n-十六酸、7-丁基苯并[a]蒽等成分的含量较高,并发现生育酚、角鲨烯等活性成分。随后采用超声强化溶剂提取法对油茶籽中的功能性因子进行提取,并探究了超声温度、pH、乙醇浓度、料液比对活性成分提取率的影响。4个因素对酚类物质提取率的影响次序为pH>超声温度>乙醇浓度>料液比,且超声温度和乙醇浓度的交互作用最强。通过响应面优化后,得到总酚的最佳提取工艺条件为超声温度45℃、乙醇浓度40%、料液比1∶10、pH 4。抗氧化活性实验结果表明,其半抑制浓度IC_(50)为39.72 mg/mL,其在抗炎、抗肿瘤领域的功效值得进一步研究。

正交试验设计优化薏苡仁脂肪提取工艺

本文以薏苡仁为材料,以薏苡仁脂肪提取率为指标,通过单因素试验和正交试验对提取时间(沸腾时间、淋洗时间、回收时间)、提取溶剂体积、提取温度3个因素进行考察,确定了使用自动索氏浸提系统提取薏苡仁脂肪的最佳工艺条件:沸腾时间35 min、淋洗时间50 min、回收时间10 min、提取溶剂体积70 mL、提取温度135℃。

不同日龄黑水虻幼虫脂肪酸组成分析

为探索不同日龄黑水虻幼虫脂肪酸组成及含量变化趋势,试验先对脂肪酸提取溶剂进行了筛选,然后采用索氏提取法及酸催化方法对不同日龄黑水虻幼虫脂肪酸进行提取及甲酯化,最后采用气相色谱与质谱联用(GC-MS)对不同日龄黑水虻幼虫脂肪酸进行分析。结果表明:(1)正己烷、石油醚、乙酸乙酯三种溶剂对脂肪酸的提取效果不同,提取的总脂肪酸分别占所有成分的96.28%、75.77%、99.32%,提取的脂肪酸种类分别为23、22、20种。(2)随着饲养时间延长,幼虫体内脂肪酸的种类增多,从5日龄到15日龄幼虫,脂肪酸增加了7种,不饱和脂肪酸的种类增加了4种。由此可见,正己烷和石油醚适合作为脂肪酸提取的溶剂,从脂肪酸种类来看,正己烷优于石油醚。不同日龄黑水虻幼虫脂肪酸组成差异较大,15日为提取黑水虻幼虫脂肪酸的最佳日龄。

基于响应面优化陈皮黄酮类有效成分的提取工艺

以陈皮为研究原料,以陈皮中的总黄酮提取率为响应值,采用单因素以及响应面实验优化索氏提取陈皮黄酮类有效成分的工艺。考察液料比、粉碎粒度、提取时间和乙醇体积分数对陈皮总黄酮提取率的影响,并采用Box-Behnken实验设计的四因素三水平响应面分析方法优化工艺。结果表明陈皮黄酮类有效成分提取的最佳工艺条件是:液料比为20∶1(mL/g);粉碎粒度为100目;提取时间为2.5 h;乙醇体积分数为35%。此条件下陈皮总黄酮的提取率为1.65%,预测提取率为1.68%,与实际值非常吻合。在此最佳工艺条件下提取的陈皮浸膏经乙醚萃取后,得到的乙醚萃取物进一步用气相色谱-质谱(gas chromatogrphy-mass spectrometry, GC-MS)法分析,共鉴定出27种挥发性成分,其中主要成分是多甲氧基黄酮类化合物。

基于低场核磁共振技术快速检测山桐子含油率的研究

为确定低场核磁共振技术是否能用于山桐子含油率的快速检测,达到准确高效、节约检测成本的目的。通过对比低场核磁共振检测法与索氏抽提法在测定山桐子含油率的差异,并考察低场核磁共振检测法的精密度和稳定性。结果表明,低场核磁共振检测法定标曲线的拟合相关系数大于0.9999,两种检测方法测定结果的绝对偏差范围在0.04%~1.40%之间,相对偏差范围在0.15%~9.86%之间,低场核磁共振检测法的精密度和稳定性良好。低场核磁共振技术可应用于山桐子含油率的检测,具有准确、快速、高效的特点。

不同提取方法对大果木姜子挥发油成分及其抑菌活性的影响

比较超声提取(UE)、微波提取(ME)、索氏提取(XZ)、水蒸气蒸馏(SD)提取的大果木姜子挥发油的化学成分,并考察其对大肠杆菌(Eco)、金黄色葡萄球菌(Sta)、枯草芽孢杆菌(Bs)、铜绿假单胞菌(Pak)的抑菌能力。结果表明:SD、UE、ME、XZ提取的大果木姜子挥发油分别鉴定出69、65、72、60种成分,相对含量分别占其总挥发油的91.382%、88.323%、85.709%、89.864%。4种挥发油对Eco的最小抑菌浓度(MIC)为SD<XZ=UE=ME,对Sta的MIC为SD<XZ=UE<ME,对Bs的MIC为XZ=UE<ME<SD,对Pak的MIC为ME<XZ=UE<SD;4种挥发油对4种供试菌的抑菌效果均高于甲醇。相关性分析表明,醇类和烃类的含量与Bs的抑制作用呈正相关。

从茶叶中提取茶多酚和咖啡因实验优化研究

茶叶中富含茶多酚、咖啡因等对人体有益的物质,如何实现其高效提取是当前困扰茶酒产业发展的瓶颈难题。本文以都匀毛尖为研究对象,基于索氏提取仪高效萃取茶多酚和咖啡因,采用单因素实验法研究了萃取剂、料液比、萃取时间、萃取温度对萃取效果的影响规律,结合正交实验法得到了高萃取率的优惠工艺条件。研究结果表明:各因素对萃取率的影响程度依次为:萃取剂(A)>料液比(D)>萃取温度(C)>萃取时间(B),最佳工艺条件为A_(3)B_(2)C_(2)D_(3),即萃取剂为酱酒,萃取时间为5 h,萃取温度为90℃,料液比为15∶1,茶多酚的萃取率可达35.05%,咖啡因的萃取率可达9.36%。本文研究成果为高品质茶酒制备提供了新的思路。

食品及饲料脂肪检测方法的优化开发

对食品、饲料、蛋及蛋制品中脂肪检测方法进行探讨,并提出一种改进后新的脂肪测定方法,以酸水解-索氏抽提法为基础,对实验条件进行改进后,新方法能够同时满足食品、饲料、蛋及蛋制品中脂肪的测定。通过数据比较,新方法的相对标准偏差为0.81%~3.76%。与不同产品脂肪检测国家标准方法相比,相对误差平均值在0.77%~1.75%。新方法的提出,为实验室及日常检验检测工作提供了一个实验更加便捷、准确度更好、污染更小、试剂回收率更好的检测方法。

不同条件下的索式抽提试验对玩具中特定元素迁移结果的影响分析

玩具样品特定元素的迁移是模拟样品在吞咽后与胃酸持续接触一段时间的条件下,从玩具样品中抽提出的特定元素。国家标准GB 6675.4—2014及欧盟标准BS EN71-3:2019+A1:2021规定了检测方法和限值,对于含油、油脂或蜡的玩具样品,在模拟测试前,国家标准中规定应将该样品包在滤纸中,使用正庚烷将上述成分去除;在欧盟标准中则规定,将该样品包在滤纸中,加入合适体积的异辛烷,保证回流时间不少于60 min,回流次数不少于10次,若上述操作完成,样品依然残留油、油脂或蜡,应继续抽提直至完全去除。本文研究了不同试剂、不同抽提时间、不同体积索式抽提装置的除油效果,在满足国家标准及欧盟标准中对特定元素迁移要求的同时,为玩具样品中的油、油脂或蜡的去除提供了一种快速有效的方法。

棘胸蛙卵油脂的提取及其体外抗氧化活性研究

试验旨在研究棘胸蛙卵油脂的体外抗氧化活性。以棘胸蛙卵为原料,采用索氏提取法提取棘胸蛙卵中的油脂,通过正交试验优化提取工艺,并对提取到的油脂进行体外抗氧化活性检验。结果显示,通过正交试验得出最佳提取条件为:采用石油醚(60~90)作为提取溶剂,提取温度为75℃,液料比为24mL/g,持续提取7h。体外抗氧化试验显示,棘胸蛙卵油脂对DPPH自由基的半抑制浓度(IC_(50)值)为298.907g/L,清除羟基自由基的IC_(50)值为1.176g/L,清除超氧阴离子自由基的IC_(50)值为12.400g/L。研究表明,棘胸蛙卵油具备一定的体外抗氧化性能,在天然抗氧化剂领域具有潜在的应用价值。