呋喃香豆素光化学毒性及其脱敏柑橘类精油的研制

调查了柑橘类精油中普遍存在的呋喃香豆素类物质及其对皮肤的光化学毒性作用.采用UV技术测定了四种市售芳香疗法用柑橘类精油:橙油、柠檬油、葡萄柚精油与佛手柑精油中呋喃香豆素的含量,并使用液-液萃取分离技术对这四种精油进行了脱呋喃香豆素类化合物试验,开发研制了四种脱敏精油.这些脱敏精油在芳香疗法使用剂量下,呋喃香豆素类化合物的含量均在20 mg/kg以下,保证了使用的安全与可靠.     

柑橘精油中呋喃香豆素的超高效液相色谱分析

建立了柑橘类精油中4种呋喃香豆素(异补骨脂素、补骨脂素、5-甲氧基补骨脂素和欧前胡素)的超高效液相色谱(UPLC)分析方法。样品经甲醇稀释定容,高速离心分离后,取上清液进样分析。采用Agilent Zorbax Eclipse Plus C18色谱柱(2.1 mm×50 mm,1.8μm)分离,以水-乙腈二元流动相梯度洗脱,流速0.3 m L·min-1,检测波长300 nm。4种呋喃香豆素在0.5~100 mg·L-1范围内呈良好线性,相关系数均达到0.999,检出限为1.5~3.0 mg·kg-1,平均回收率为97.5%~105.6%,相对标准偏差为0.4%~2.9%(n=3)。采用已建立的方法对25批柑橘类精油样品进行测定,发现1个批次的甜圆柚油中含有5-甲氧基补骨脂素,质量分数为60.5 mg·kg-1。     

精油的芳香疗法

简要介绍了精油的提取方法以及精油的一些治疗功效。回顾了精油芳香疗法的历史和现状。介绍了芳香治疗用精油的不同用法,以及精油的作用机理,并对精油的芳香疗法的市场前景进行了概述。     

芳香疗法--精油的保健和治疗作用

概述了芳香疗法的历史和现状,简要介绍了精油的提取方法和治疗功效,根据芳疗用精油的不同用法,论述了它们的作用机理,展望了芳疗用精油的市场前景。     

6,7-二羟基香豆素的研制

以苯醌和醋酐为原料,通过酰化反应制备了中间体1,2,4-三乙酰氧基苯,再与苹果酸发生环合反应制得6,7-二羟基香豆素。     

3-芳基香豆素及其衍生物的研究进展

3-芳基香豆素及其系列衍生物因具有重要的生物、医药活性及良好的光学性能而受到人们的广泛关注.本文概述了近年来3-芳基香豆素及其衍生物的主要合成方法,并介绍了这些方法在合成中的优缺点,为3-芳基香豆素的进一步合成研究提供依据.     

芳香疗法中使用精油存在的危险性（下）

(接上期第 2 7页 )　　 3.2　精油致胎儿先天缺陷已经证实对实验动物有强烈致畸胎作用的唯一的精油成分为乙酸桧酯 (ｓａｂｉｎｙｌａｃｅｔａｔｅ) ,试验所用的精油是灌木香茶菜油 (Ｐｌｅｃｔｒａｎｔｈｕｓｆｒｕｔｉｃｏｓｕｓ ,无商品精油供应 ) ,其中乙酸桧酯的含量超过60 % [2 3] 。其他含乙酸桧酯的精油还有桧油 (Ｊｕ ｎｉｐｅｒｕｓｓａｂｉｎａ ,乙酸桧酯含量 2 0— 5 3% )、Ｊｕｎｉｐｅｒｕｓｐｆｉｔｚｅｒｉａｎａ(无商品精油供应 )以及西班牙鼠尾草油(Ｓｐａｎｉｓｈｓａｇｅｏｉｌ,Ｓａｌｖｉａｌａｖａｎｄｕｌｉｆｏｌｉ…     

香豆素-3-羧酸及其酯的合成研究

在无水乙醇中,以六氢吡啶为催化剂,通过水杨醛与丙二酸二乙酯的Knoevenagel缩合反应合成了香豆素-3-羧酸乙酯,再经水解、酸化得到香豆素-3-羧酸。对影响香豆素-3-羧酸乙酯收率的原料配比、反应时间、催化剂的选择和用量进行了研究。所得最佳合成条件为:水杨醛与丙二酸二乙酯物质的量比1.0∶1.4,1 mol六氢吡啶用量0.8 mL,反应时间2 h,在最佳工艺条件下,香豆素-3-羧酸乙酯的收率87.6%,质量分数为99.6%。通过IR光谱对产品进行了表征。     

芳香疗法中使用精油存在的危险性（上）

指出了芳香疗法医师、各种芳香疗法出版物的作者和公众对精油毒性存在着各种误解以及由此引发的芳香疗法应用中的各种混乱现象。比较了各种给药途径 ,认为吸入方式在所有给药途径中最安全 ,并强调了剂量对芳香治疗安全性的重要意义。含酚类和芳香醛类化合物的精油也可安全地用于皮肤制剂。论述了月经和孕期的激素和生理过程 ,精油的通经作用是刺激垂体前叶产生的一种次生作用 ,而不是通过外加激素样物质产生的结果 ,并由此得出妊娠期使用具有通经作用的精油相当安全。列出了高血压、癫痫和肾病患者应忌用的精油以及精油中毒时应采取的措施。此外 ,精油具有光毒性、致敏和刺激作用 ,会直接引发皮肤灼伤、香料皮炎和过敏反应等 ,强调精油在使用前要进行“斑贴试验”以避免使用精油时发生过敏反应。总之 ,精油的毒理学对芳香疗法的安全性至关重要 ,要用药理学的方法科学地评价精油的毒性 ,并结合临床实践提出精油的适用性及在应用过程中可能引发的危险提出警告并给予正确指导。     

渗透汽化分离精油中挥发性芳香化合物的研究进展

精油及其挥发性组分在化妆品、食品和药品工业、农业及食品保鲜等领域有着广泛的应用潜力。目前挥发性精油的分离主要采用的是分段蒸馏技术,该技术存在成本高、能耗大且容易造成精油组分破坏等缺陷,因此其应用受到了极大的限制。渗透汽化（pervaporation,PV）是一种用于液体混合物分离的新型膜分离技术,具有高效节能、环境友好和容易操作等优点,特别是能够实现热敏性物质的高效单级分离,因此在挥发性精油的分离和挥发性芳香化合物组分精制等方面具有巨大的应用潜力。本文系统总结了渗透汽化技术在挥发性精油分离领域的最新进展,综述了用于分离挥发性精油的渗透汽化膜材料、分离工艺及其应用现状,并对渗透汽化用于大规模分离挥发性精油过程中面临的挑战进行了讨论。     

芳香疗法研究进展

从芳香疗法的发展历史、给药方式、研究应用、作用机理及其安全性等方面进行了综述,并对芳香疗法研究应用前景进行了展望.     

Extraction of oleic acid from soybean oil and jojoba oil-phase diagrams

Formamide,N-methylformamide,N-dimethylformamide, dimethylsulfoxide, 1,2-butanediol, and 2-butane-1,4-diol were considered as potential extractants of fatty acids from soybean and jojoba oils. Ternary liquid-liquid phase diagrams at 298.15 K, distribution, and selectivity coefficients of oleic acid are reported. Of the investigated solvents, onlyN-methylformamide and 1,2-butanediol have desirable extraction characteristics.     

离子液体超声-微波协同制取洋葱精油

以离子液体［BMIM〖DK〗］PF₆作为生物催化介质,结果显示洋葱蒜氨酸酶在含25%［BMIM］PF₆催化体系中的活性比在纯缓冲液介质中明显要高,对高温变性作用的抵抗能力也相应增强,但若离子液体浓度过高会对酶催化作用的发挥产生阻碍。以洋葱蒜氨酸为底物,测得离子液体［BMIM］PF₆/缓冲液两相体系中蒜氨酸酶的米氏常数为0.591 mmol·L^-1,最大反应速率为0.316 mmol·L^-1·min^-1,V_max/K_m约为缓冲液单相体系中的两倍。实验还尝试发挥疏水性离子液体［BMIM］PF₆作为生物催化介质和萃取剂的双重功能,并将其与超声-微波协同萃取技术相结合应用于洋葱精油制取的酶解和萃取过程,明显提高了酶解效率和精油得率,将制得的精油经GC-MS分析,共鉴定出22种物质,其中19种为含硫化合物。     

Preparation of nanoclay incorporated PAN fibers by electrospinning technique and its application for oil and organic solvent absorption

In this work, polymer nanofibers (PAN/n-OMMT clay) were successfully produced by using an electrospinning process. The PAN/n-OMMT nanofibers were studied as an oil and solvent absorbent material due to their super hydrophobicity and super oleophilic properties. The generated composite nanofibers were found to have a very high oil and solvent absorption capacity in the case of 3% n-OMMT clay loading. It showed excellent absorption capacity up to 160 times its own weight for motor oil. The findings reported in this work might provide a fast and facile approach for the removal of oils and organic solvents on water surfaces.     

Free energy coupling of electron transfer and ion transfer in two-immiscible fluid systems

Free energy coupling of electron and ion transfers across a liquid-liquid interface is treated theoretically assuming electroneutrality of each phase and complete dissociation of electrolytes. A general method is presented for calculating the equilibrium inner potential difference between the two phases and equilibrium concentrations of redox species, as well as other ionic components from given initial concentrations, values of standard electrode potential of redox couples, and of standard ion transfer potential of other ionic components. The ion-electron exchange across the interface is exemplified for several simpler cases. The volume ratio has a dramatic effect on the equilibrium. The partition of indifferent-electrolyte ions can drive the redox reactions before the onset of electrolysis and can significantly alter the initial conditions for electron transfer studies at the liquid-liquid interface.     

香根草精油微胶囊的制备及其体外抗炎作用

以明胶和壳聚糖为壁层材料,以香根草精油为囊芯,采用复凝聚法制备香根草精油微胶囊。通过单因素和正交实验筛选微胶囊最佳制备工艺,采用SEM、粒度仪、Zeta电位仪和FTIR对样品进行了表征。测定微胶囊于pH 1.5和7.4时香根草精油的释放率,观察微胶囊对小鼠RAW 264.7细胞的体外抗炎作用。结果表明,香根草精油用量0.3 g,壁材用量1.0 g(其中明胶与壳聚糖的质量比为30∶2)时,封装率可达90.96%;制备的微胶囊表面呈球形,微胶囊粒径为2.303μm,电位–33.8 mV,具有良好的稳定性,封装效果好;该微胶囊于pH 7.4下释放度较佳,72 h内累积释放达87.49%;细胞实验表明,该微胶囊(质量浓度为60、90、120 mg/L)安全无毒,能有效抑制RAW 264.7细胞白介素-1β(IL-1β)、白介素-6(IL-6)和肿瘤坏死因子α(TNF-α)的分泌。香根草精油微胶囊处方工艺简单,质量稳定,抗炎活性良好。     

压榨法与蒸馏法提取柑橘香精油的比较研究

为寻找一条适合工业连续生产的低成本、低能耗、高效率的柑橘香精油生产工艺路线,用水蒸气蒸馏和压榨法提取柑橘香精油。通过对两种方法比较发现:水蒸气蒸馏的柑橘油为无色液体,出油率为1.2%～2.1%,增加破碎度和添加氯化铵可以提高出油率;利用压榨法生产的香精油,色泽为淡黄色液体,出油率较低,为1.0%～1.6%,但有较佳的气味,其香气更接近于天然鲜橘果香,压榨后的残渣仍可用水蒸气蒸馏法提取得到部分橘油。压榨法适合于工业大规模连续生产柑橘香精油。     

Preparation and characterization of porous acrylate terpolymer nanocomposite for removal of diesel oil from artificial seawater

The present work deals with the preparation of magnetic acrylate terpolymer nanocomposite by emulsion polymerization. This nanocomposite was applied for the removal of diesel oil from artificial seawater by magnetic separation. Magnetic terpolymer nanocomposite was characterized by Fourier transform infrared (FTIR) spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Specific surface area and pore size distribution were measured by the Brunauer–Emmett–Teller (BET) method. Contact angle (CA) measurement showed superhydrophobic properties of magnetic acrylate nanocomposite. Kinetics and isothermal studies indicate that oil sorption fits the second-order kinetic model and the Langmuir isotherm. Magnetic acrylate terpolymer can be regenerated for six cycles.     

Preparation of PAN@PU coaxial electrostatic spun nanofibers for oil/water separation

Coaxial electrostatic spinning (co-electrostatic spinning) technology has greatly expanded the versatility of the preparation of core–shell polymer nanofibers and has found a wide range of applications in the environmental and biological fields. Here we present a method for the preparation of coaxial nanofibers using polyacrylonitrile (PAN) and polyurethane (PU) as raw materials. It was found that the tensile strength ranges from 2.14 to 4.07 MPa with the increasing spinning speed of the nucleated PU layer, and the elongation at break was up to 95.09% for M_6:4, which was three times higher than that of the original M_PAN (30.54%), and the toughness of the nanofiber film was also significantly improved. Finally, the oil/water separation capacity of the coaxial nanofiber membrane was investigated, and the results showed that the separation fluxes for various oil compounds ranged from 2380.18 to 3130.17 L·m⁻²·h⁻¹, with separation efficiencies above 99%. This study not only investigates the effect of different flow rates of core (PU)/shell (PAN) on the performance of coaxial electrostatic spun nanofiber membranes, but also provides a new insight into the coaxial electrostatic spinning process.