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Search Results: 1 - 10 of 3458 matches for " fatty alcohols "
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Quality Evaluation of Policosanol Film-Coated Tablets by Simultaneous Determination of Eight Ingredients Using GC- FID and GC-MS  [PDF]
Han Yao, Chunmin Wei, Haibo Song, Ruichen Guo
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2012, DOI: 10.4236/jasmi.2012.21005
Abstract: A new and simple gas chromatographic (GC) method using flame ionization detector (FID) and mass spectrometry (MS) for the simultaneous determination of eight fatty alcohols in 10 mg policosanol film-coated tablets was established and applied to the quality control (QC) of policosanol film-coated tablets. A DB-35MS capillary column (30 m × 0.32 mm, 0.25 um) was employed for the separation. GC-FID was used to quantitatively analyze the eight ingredients with 1-eicosanol as internal standard, three of which were identified using GC-MS due to the lack of standard. The linearity, accuracy, precision, stability, robustness and sensitivity within the detection limits were evaluated. The average recovery of the method was 96.3-100.4% and linearity was (R > 0.999). The average drug content was found to be 96.8% of the labeled amount (10 mg).
Extraction and characterization of seed oil waxes by using chromatographic techniques
Rizwana K Soomro and Syed Tufail H Sherazi
International Journal of Industrial Chemistry , 2013, DOI: 10.1186/2228-5547-4-9
Abstract: GC-MS was used for the characterization of the various classes of three different seed oil waxes. The results indicated that seed oil wax has the potential to be used in the cosmetic and pharmaceutical industry due to its better composition of long chain fatty acids and fatty alcohols.
Reduction of evaporation of natural water samples by monomolecular films
Gugliotti, Marcos;Baptista, Mauricio S.;Politi, Mario J.;
Journal of the Brazilian Chemical Society , 2005, DOI: 10.1590/S0103-50532005000700015
Abstract: the ability of monomolecular films of fatty alcohols in reducing evaporation of natural water samples collected from two reservoirs in s?o paulo (guarapiranga and billings) was studied in the laboratory. evaporation reductions were determined directly by measuring the volume of water evaporated from the test recipients after a certain period of time. mixed films of hexadecanol and octadecanol showed high potential of evaporation reduction (up to 57%) and persistence on the water surface of ca. 48 hours. a brief discussion on the better efficiency of these mixed films in reducing water evaporation is also presented.
Hidrogenación de Metil Oleato con Catalizadores de Ru-Sn/Al2O3: Método Sol-gel vs. Impregnación
Echeverri,David A; Rios,Luis A; Marin,Juan M;
Información tecnológica , 2010, DOI: 10.4067/S0718-07642010000300009
Abstract: in this work, the effect of the preparation method (sol-gel vs. impregnation) over conversion and selectivity to oleyl alcohol in the hydrogenation of methyl oleate over ru-sn/al2o3 catalysts at 270oc and 5 mpa was evaluated. the catalysts were characterized by sem-eds, tpr, xrd and surface area by nitrogen adsorption. the sol-gel method produced high dispersion of metals in the support, however catalysts prepared by sol-gel method were less reducible. for both methods an optimum sn/ru atomic ratio that allowed higher percentage of unsaturated alcohol was found. for the impregnation method this atomic ratio was 2 and for sol-gel method was 1. however, higher conversions and higher selectivity toward the oleyl alcohol were obtained with the impregnation method, using the optimum atomic ratio,
Validación de un nuevo método analítico por CG con columna capilar para la determinación de alcoholes de alto peso molecular en policosanol ingrediente activo
González Canavaciolo,Víctor L; Sierra Pérez,Roxana; Velásquez G,Caridad;
Revista Colombiana de Ciencias Químico - Farmacéuticas , 2008,
Abstract: policosanol is a mixture of 8 long chain primary aliphatic alcohols (c24-c34), isolated and purified from sugar cane (saccharum officinarum l.) wax, wich cholesterol-lowering efficacy, safety and tolerability has been demonstrated. several methods for determing policosanol by packed gc column have been previously validated. however, the advantages achieved with the capillary gc make it worldwide currently extended and overcome to the packed ones. a new gas chromatographic method using a capillary column was developed and validated for the determination of the fatty alcohols that compose policosanol active ingredient. the alcohols were analyzed as trimethylsilyl derivatives. good linearity (r2 = 0,9954, cvresponse=1,07%, cvslope=1,89% and the confidence interval included the zero, then there was no bias) and accuracy (mean recovery = 100,45%) of the method were proven over a range of 80-120% of the nominal concentration. it was also proved its specificity even when samples were subject to stress conditions. repeatablility and intermediate precision at the nominal 100% value fulfilled the acceptance criteria (< 2%). ruggedness was evaluated through an intralaboratory experimental design, in which seven operational changes were made, and there was not found any effect on the observed results. the method was sussefully validated being suitable for the quality control process and the stability studies of this active ingredient.
Estudios organolépticos, fisicoquímicos, microbiológicos e interacción con excipientes farmacéuticos de un extracto purificado de cera de Apis mellifera
González Canavaciolo,Víctor Luis; Martínez álvarez,Luis; Marrero Delange,David; Sierra Pérez,Roxana Caridad;
Revista Cubana de Farmacia , 2010,
Abstract: the d002, an antioxidant active ingredient extracted from the apis mellifera bees wax was characterized from the physicochemical point of view analyzing its interaction with excipients of pharmaceutical interest. the d-002 is a creamy white odourless fluid powder with losses by £ 1 % dry; it is water and ethanol insoluble and very slightly soluble in other organic solvents. its composition, determined by gas chromatography was: 1-tetracosanol (6-15 %), 1-hexacosanol (7-20 %), 1-octacosanol (12-20 %), 1-triacontanol (25-35 %, 1-dotriacontanol (18-25 %) and 1-tetratriacontaol (£ 7,5 %) for 3 85 % of purity. it remained stable during 5 years in the iv climatic zone and its analysis by differential scanning calorimetry showed 2 fusion transitions at 59.0 and 81.1 °c. without decomposition, a high thermal stability up to 200 °c, as well as a lack of interactions with lactose, starch, sodium croscarmelosa, polyvinylpyrrolidone, microcrystalline cellulose, and magnesium stearate allowing the use of these excipients in tablets formula.
Voltammetric studies on free radicals of lower fatty alcohols
Junfeng Song,Huafeng Fu,Wei Guo
Chinese Science Bulletin , 2001, DOI: 10.1007/BF03184326
Abstract: In this work, both generation and reduction processes of the α-radicals of lower fatty alcohols were studied by voltammetry in lower fatty alcohols/peroxydisulfate/phosphate buffer system. Experimental results showed that such three reactions were successively completed at negative potential on mercury electrode surface: (i) sulfate radical anion SO 4 was generated electrochemically from one-electron reduction of peroxydisulfate ion S2O 8 2 , (ii) the SO 4 oxidized lower fatty alcohols to the corresponding α-radicals and (iii) the α-radicals were reduced in one-electron and one-proton addition to produce their own reduction waves. The apparent free energy ΔrGm of the α-radicals of lower straight-chain fatty alcohols such as methanol, ethanol, propanol, butanol and pentanol obtained were 107.09, 116.74, 122.53, 126.39 and 129.28 kJ · mol/L, respectively. The proposed method is more simple and convenient than the current approaches based on the radical-chain reaction for studying alcohol oxidation.
Phytoconstituents from Alpinia purpurata and their in vitro inhibitory activity against Mycobacterium tuberculosis
Villaflores Oliver,Macabeo Allan Patrick,Gehle Dietmar,Krohn Karsten
Pharmacognosy Magazine , 2010,
Abstract: Alpinia purpurata or red ginger was studied for its phytochemical constituents as part of our growing interest on Philippine Zingiberaceae plants that may exhibit antimycobacterial activity. The hexane and dichloromethane subextracts of the leaves were fractionated and purified using silica gel chromatography to afford a mixture of C 28 -C 32 fatty alcohols, a 3-methoxyflavone and two steroidal glycosides. The two latter metabolites were spectroscopically identified as kumatakenin (1), sitosteryl-3-O-6-palmitoyl-b-D-glucoside (2) and b-sitosteryl galactoside (3) using ultraviolet (UV), infrared (IR), electron impact mass spectrometer (EIMS) and nuclear magnetic resonance (NMR) experiments, and by comparison with literature data. This study demonstrates for the first time the isolation of these constituents from A. purpurata. In addition to the purported anti-inflammatory activity, its phytomedicinal potential to treat tuberculosis is also described.
Fracciones lipídicas obtenidas a partir de frutos de Serenoa repens recolectados en Cuba
Rodríguez Leyes,Eduardo A; González Canavaciolo,Víctor L; Marrero Delange,David; Leiva Sánchez,ángela T;
Revista Cubana de Plantas Medicinales , 2012,
Abstract: introduction: lipid extracts from the fruits of serenoa repens, a native palm from the united states of america, are used to treat benign prostate hyperplasia. although this species was introduced in the national botanic garden of cuba some years ago, the lipid extracts of its fruits had not been studied yet. objective: to determine the main organoleptic, physical and chemical characteristics of lipid extracts from the fruits of s. repens harvested in cuba. methods: dried fruits and fresh ripe fruits of s. repens were harvested. fresh fruits were dried at room temperature and at 80 oc. the three groups of dried fruits were grounded and extracted with hexane in s?xhlet equipment. the main characteristics of the dried lipid extracts were determined. the studied components were determined by gas chromatography, in some cases with mass spectrometry detection. results: organoleptic and physical characteristics as well as the contents of fatty acids (major components) and ethyl esters of the studied extracts agreed with that described in literature, whereas those of sterols and fatty alcohols were higher than those previously reported for this species. some fatty alcohols not previously reported in these extracts, that is, 1-eicosanol, 1-docosanol, 1-heptacosanol, 1-nonacosanol, 1-dotriacontanol and 1-tetratriacontanol.were also identified. conclusions: generally speaking, the lipid extracts from the fruits of s. repens harvested in cuba presented characteristics similar to those reported for the extracts of this species, although some differences were also found, such as the content of sterols and fatty alcohols and the presence of some fatty alcohols not previously reported in the literature.
Antibacterial Activity of Long-Chain Fatty Alcohols against Staphylococcus aureus
Naoko Togashi,Akiko Shiraishi,Miki Nishizaka,Keisuke Matsuoka,Kazutoyo Endo,Hajime Hamashima,Yoshihiro Inoue
Molecules , 2007, DOI: 10.3390/12020139
Abstract: The antibacterial activity against Staphylococcus aureus of long-chain fatty alcohols was investigated, with a focus on normal alcohols. The antibacterial activity varied with the length of the aliphatic carbon chain and not with the water/octanol partition coefficient. 1-Nonanol, 1-decanol and 1-undecanol had bactericidal activity and membrane-damaging activity. 1-Dodecanol and 1-tridecanol had the highest antibacterial activity among the long-chain fatty alcohols tested, but had no membrane-damaging activity. Consequently, it appears that not only the antibacterial activity but also the mode of action of long-chain fatty alcohols might be determined by the length of the aliphatic carbon chain.
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