A New Diterpenoid and other Constituents from Acanthopanax Brachypus Harms

Phytochemical investigation of the stem bark of Acanthopanax brachypus afforded a new labdanetype diterpene glycoside, 3α‐trans‐sinapoyloxy‐jhanol 18‐O‐β‐D‐glucopyranoside ( 1 ), together with four known compounds, including one diterpene acid, acanthoic acid ( 2 ), one coumarin, isofraxidin ( 3 ), one phenolic glycoside, sasanquin ( 4 ), as well as one chalcone glycoside, okanin 4‐methyl ether‐3′‐O‐β‐D‐glucopyranoside ( 5 ). All of the structures were characterized by means of spectroscopic methods, including ¹H, ¹³C, 2D‐NMR and HR‐MS, as well as chemical methods and comparison with the literature data.     

Phenols in whisky

Summary Twelve volatile phenols were identified in whisky by combined gas chromatography-mass spectrometry. Of these phenols 2,4-dimethylphenol was found for the first time in the aroma of whisky. The content of phenol, o-, m-, and p-cresol, guaiacol, p-ethylphenol, p-ethylguaiacol and eugenol in whiskies originating from different countries was determined by gas chromatography as their 2,4-dinitrophenyl ethers using electron capture detection. The results show that Scotch whiskies differ from others in the content of o-, m-, and p-cresol. The odour threshold values of phenols studied were determined in a 10% (v/v) ethanol-water mixture and in some cases also in the whiskies. Cresols have been found to make contribution to the aroma of Scotch whisky.Presented at the 14th International Symposium on Chromatography London, September, 1982     

Antitumor activity of stilbenoids and flavonoids isolated from Acanthopanax brachypus

This report is the first to detail the antitumor activity of Acanthopanax brachypus, a species well recognized by eastern folk medicine. Four stilbeniods and nine flavonoids have been isolated from stem bark of the plant. The isolates have been tested for their antitumor activity against selected human cancer cell lines (HgpG-2, MCF-7, K-562, and A-549). Even though three of the compounds have shown high to moderate cytotoxicity against certain cell lines (IC₅₀ of 4.5 to 6.5 μg/mL), in most of the experiments little or no anticancer activity has been revealed.     

Measurement of Phenols in Automobile Exhaust

Abstract

Methods were investigated to measure exhaust emission rates of individual low-molecular-weight phenols from gasoline and diesel vehicles driven on a chassis dynamometer using the FTP driving cycle. An extraction procedure to isolate the phenols from exhaust scrubs was evaluated. Separation of individual phenols was done by gas chromatography, with detection by a flame ionization detector. Phenol identifications were confirmed by mass spectroscopy. Results of a limited survey of gasoline and diesel vehicles are reported.     

载溴树脂溴化酚类的研究

用简便方法制备得载溴树脂并用于酚类的溴化,当采用不同摩尔比的载溴树脂时,有选择地得到一溴、二溴及三溴代物,并有较高的产率,同时该树脂具有良好的稳定性。     

Assay of Phenols and Arylamines via Peroxidatic Coupling

Abstract

Assay procedures are described for phenols and arylamines involving oxidative coupling, employing peroxide-peroxidase, to form the highly colored indaniline and indamine dyes, respectively. The phenols and arylamines are assayable in the 10^?6 to 10^?5 molar range. Appropriate conditions for maximum dye formation are described.     

取代苯酚中共振增强的分子内氢键

根据晶体结构资料，计算了59个邻位取代苯酚中分子内氢键的几何．在STO－3G水平上计算了一些分子中原子部分电荷．结果表明，酚基氧与苯环上碳之间的键长，酚基上氢原子的部分电荷，酚基所在位置处的苯环环内角与取代苯酚的酸常数pKa均有近似线性关系，当邻位上存在硝基或羰基时，内氢键由于共振而得到显著的增强，据此可说明这一类酚的显著酸性     

刺五加中黄酮类化合物的微波辅助提取研究

利用微波辅助提取法(MAE)提取刺五加中的黄酮类化合物,通过正交实验,考察了微波提取条件(包括溶剂、微波辐射时间、提取压力和料液比)对刺五加中总黄酮提取率的影响,结果表明：溶剂为50％乙醇,提取压力为700kPa,提取时间为10min,料液比为1：20时,提取率最佳。与索氏提取法相比较,提取率可提高40％。     

Phenols removal by immobilized tyrosinase reactor in on-line high performance liquid chromatography

The development of an immobilized enzyme reactor (IMER) based on tyrosinase immobilized on aminopropyl-controlled pore glass (AP-CPG) for the removal of phenols from model aqueous solutions was reported. To elucidate the influence of the substrate nature, the apparent (V'max, K'm) and the inherent (Vmax, Km) Michaelis-Menten constants were determined by Lineweaver-Burk method and the external diffusional contributions on measured enzyme activities were removed by a graphical method. The dephenolization process was realized by recycling the phenol solutions through the bioreactor connected to a chitosan trap in order to remove the colored quinone-type products of the tyrosinase reactions. The results indicated that a complete removal of phenol derivatives in the range of 150-300 min, with the exception of 60% removal for phenol reached in 400 min, was obtained. The observed sequence: cresol > 4-methylcathecol > catechol > 4-Cl-phenol phenol was in accordance to the V'max/K'm values.     

Microwave Assisted-extraction of Flavonols from Acanthopanax Senticosus Harms and High-performance Liquid Chromatography Analysis

Flavonols were extracted from Acanthopanax Senticosus Harms by Soxhlet extraction(SE),atmospheric pressure microwave-assisted extraction(AMAE) and pressurized microwave-assisted extraction(PMAE).The influences of experimental conditions,such as concentration of ethanol in the eluent,microwave irradiation time,etc.on the extraction yield were studied.Four flavonols(hyperin,rutin,quercitrin and quercetin) in the extracts were determined quantitatively by HPLC method.The experimental results demonstrate the ad...     

加速溶剂萃取-气相色谱-质谱法测定固体废物中酚类化合物

提出了气相色谱-质谱法测定固体废物中12种酚类化合物残留量的方法。样品以丙酮-二氯甲烷(2+3)混合液为萃取剂,经加速溶剂萃取仪提取后,在K-D浓缩装置上浓缩至1 mL,经硅胶柱净化后,用丙酮-二氯甲烷(1+9)混合液淋洗后再经K-D浓缩至1 mL,通过HP-5 MS石英毛细管色谱柱(30 m×0.25 mm,0.25μm)分离,采用电子轰击离子源选择离子监测模式进行质谱测定。12种酚类化合物的检出限(3S/N)在9.60～18.5μg.kg-1之间。以空白土壤样品为基体进行回收试验,测得回收率在74.7%～108.4%之间,测定值的相对标准偏差(n=7)均小于7.5%。     

Organic-Phase Enzyme Electrode for the Determination of Phenols in Olive Oils

Abstract

A rapid procedure for determining phenols in olive oils, based on an organic-phase enzyme electrode, is described. Direct assays are performed in chloroform solutions which support the tyrosinase activity. This class (phenol)-specific enzyme strongly adheres to the surface of the graphite transducer. The resulting wall-jet detector offers effective flow injection operation, with a detection limit of 4×10^?7 M (0.8 ng) phenol and sample frequency of 60 h^?1. Applicability to olive-oil samples of different origins is illustrated.     

Inhibition of Ru Complex Electrochemiluminescence by Phenols and Anilines

The effect of 30 phenols and anilines on typical Ru complex electrochemiluminescence (ECL) was systematically investigated under different conditions. It was found that all the tested compounds showed an ECL inhibiting signal. The magnitude of ECL inhibition was related to the position of the substituting group in the benzene ring and decreased in the following order: meta‐>ortho‐>para‐. The oxidation potential of the tested compounds, the ECL spectra and UV‐visible absorption spectra of Ru(bpy) /tripropylamine (TPrA) in the presence of phenols and anilines, and the direct ECL between Ru(bpy) and phenols/aniline were studied. The mechanism of ECL inhibition has been proposed due to energy transfer from the excited state Ru(bpy) to a quinone or ketone or their polymer formed by electro‐oxidation of phenols and anilines. The potential of analytical application was explored by use of the inhibited ECL. The results demonstrate that numerous compounds are detectable with the detection limits in the range of 10^?8–10^?9 mol/L for Ru(bpy) /TPrA system and in the range of 10^?6–10^?7 mol/L for Ru(bpy) /C₂O system, respectively.     

Spectrophotometric Determination of Phenols and Cyanides After Distillation from Natural Waters

Abstract

Total phenols were determined by molecular spectrophotometry, after distillation, complexation with 4-aminoantipyrine and extraction into chloroform. Cyanides were also determined spectrophotometrically after distillation from the acidified samples, and complexation in moderate acidic solution with barbituric acid. The dynamic ranges were 0 – 100 μg L^?1 for total phenols and 0 – 30 μg L^?1 for cyanides. The above methods were applied in the analysis of river, lake and stream waters collected from Northern Greece. The seasonal and spatial variation of concentrations was evaluated by two-way ANOVA. Background levels (4 – 12 μg L^?1 for total phenols and 0.3 – 3 μg L^?1 for cyanides), were found in almost all surface waters, with some exceptions.     

酚类聚合物在水相胶束中的酶促合成

本文报道辣根过氧化物酶在水相胶束中催化聚合取代酚类的研究。水相胶束中酶催化活力高，产物分子量均一；通过调节表面活笥剂和单体的浓度，可以有效地控制产物的分子量，从而建立了不同聚合度有机纳米材料酶促合成的新方法。产物具有较强的蓝紫色荧光及较好的耐热性能，是一种很有应用前景的蓝光材料。     

反相高效液相色谱分离-安培法检测酚类化合物

本文报道了RP-HPLC-安培法检测测定酚类化合物的条件。在Shim-pack CLC-C_8柱上用含0.05mol/L NaH_2PO_4缓冲溶液的5％甲醇水溶液洗脱分离,于E+1.0V处检测。线性范围在0～7μg/ml,检测限达ng/ml。     

Sesquiterpenoids from the Root Bark of Acanthopanax leucorrhizus and Their Biological Activities

Three furoeremophilane‐type sesquiterpenoids, including one new, 1α‐acetoxy‐6β‐(benzoyloxy)‐10β‐hydroxy‐9‐oxofuroeremophilane ( 1 ), and two known, 1β,6β‐diacetoxy‐9‐oxofuroeremophilane ( 2 ) and (6α)‐furoeremophilan‐14,6‐olide ( 3 ), were isolated from the root bark of Acanthopanax leucorrhizus from China. Their structures were elucidated on the basis of comprehensive spectroscopic analyses, including IR, HR‐ESI‐MS, 1D‐ and 2D‐NMR experiments. A preliminary bioassay revealed that compound 1 exhibits weak cytotoxicities against the human tumor cell lines MCF‐7 and SMMC‐7721 with the IC₅₀ values of 75.12±1.69 and 168.36±2.01 μg/ml, respectively. Compound 1 and 2 showed moderate activities against Escherichia coli with the MIC values of 32 and 64 μg/ml, respectively.     

刺五加叶中黄酮类化合物的分析

利用电喷雾多级串联质谱 (ESI MSn)技术 ,分析了刺五加叶中黄酮类化合物 ,并根据黄酮类化合物的特征显色反应 ,采用紫外 可见分光光度法 ,对刺五加叶中总黄酮的含量进行了测定。分析结果表明 :刺五加叶含有槲皮素及其相关的黄酮甙类化合物 ,其含量达 37.2 5 %。