斑蝥炮制前后脂肪酸成分的GC-MS分析

目的:分析斑蝥炮制前后脂肪酸组成。方法:石油醚提取斑蝥脂肪油,甲酯化处理后采用气相色谱-质谱联用技术分析化合物组成,用峰面积归一化法确定各成分相对含量。结果:从炮制前后的斑蝥脂肪油中共分离鉴定出10种脂肪酸成分,脂肪酸组成以油酸、硬脂酸、亚油酸为主。结论:炮制对斑蝥脂肪酸组成影响不大。本试验可为斑蝥炮制前后的成分研究提供理论依据。     

酸藤子脂肪酸类成分的GC-MS研究

目的:研究酸藤子的脂肪酸类成分。方法:酸藤子根部以95%乙醇提取,用石油醚对提取物进行萃取,所得萃取部位经甲酯化处理后,采用气相色谱-质谱(GC-MS)联用技术进行分析鉴定;酸藤子枝叶用石油醚提取,所得提取物也用GC-MS联用技术进行分析鉴定。再用峰面积归一化法测定各成分的相对含量。结果:酸藤子根部共分离出67个色谱峰,鉴定了其中28个,占流出峰总面积的73.48%,主要脂肪酸成分为8,11-亚油酸(19.10%)、8-油酸(13.01%)与棕榈酸(12.29%)。酸藤子枝叶共分离出30个色谱峰,鉴定了其中12个,占流出峰总面积的91.60%,主要脂肪酸成分为棕榈酸(52.16%)。结论:酸藤子根部和枝叶的脂肪酸类成分有差异。本试验结果可为酸藤子的深入开发提供一定的科学依据。     

长鬃蓼脂肪酸成分研究

目的分析长鬃蓼的脂肪酸含量及其脂肪酸组成。方法以索氏提取法提取长鬃蓼的脂肪油,采用气相色谱-质谱分析鉴定脂肪酸成分。结果鉴定了长鬃蓼的18个脂肪酸成分、2个甾类化合物和植醇,占色谱总出峰面积的82.39%;脂肪酸组成以亚油酸、油酸和棕榈酸为主,不饱和脂肪酸占脂肪酸总量的60.79%。结论长鬃蓼脂肪酸成分主要为不饱和脂肪酸,所含脂肪酸具有很好的药理活性,为开发利用长鬃蓼资源提供了科学依据。     

紫金龙脂溶性化学成分的研究

目的研究紫金龙脂溶性化学成分。方法采用气相色谱-质谱联用技术分离鉴定脂溶性成分,用峰面积归一化法测得相对百分含量。结果从中鉴定出37个组分,占峰面积的88.33%。结论紫金龙脂溶性成分主要为生物碱,脂肪酸酯和甾醇类化合物。     

猫爪草中脂肪酸成分的GC—MS分析

目的:采用 GC-MS 法对猫爪草中的脂肪酸进行分析。方法:使用 RTX-5MS(30 m×0.25 mm,0.25 μm)弹性石英毛细管色谱柱,采用程序升温,进样口温度为280℃,分流比为20:1,流速为1.1 mL·min~(-1),分析时间共20 min,对猫爪草提取物的甲酯化样品进行 GC-MS 分析,质谱图用 NIST 谱库检索,鉴定各种脂肪酸,并用色谱峰面积归一化方法测定其相对含量。结果:鉴定出18种脂肪酸,主要成分亚油酸、软脂酸、油酸、亚麻酸和硬脂酸的相对百分含量分别为48.11%,21.37%,13.75%,8.86%,1.75%。结论:本法简便、快速,灵敏度高。     

藏药萝卜秦艽挥发油成分的GC-MS分析研究

目的研究萝卜秦艽块根的挥发油化学成分。方法采用气相色谱-质谱联用仪对萝卜秦艽块根的挥发油成分进行了分析研究。结果从分离出的30多个峰中鉴定出其中27个化合物,并以全部峰面积作为100%,利用归一化法计算出各组分在挥发油中的相对含量。结论萝卜秦艽块根中挥发油的主要成分为烷烃类和有机酸及其酯类化合物,其中十六烷酸、油酸、亚油酸等成分含量较高。     

金门高粱酒中的芳香性成分的GC-MS分析

目的:研究金门高粱酒的芳香性成分。方法:采用气相色谱-质谱(GC-MS)联用技术对金门高粱酒中的芳香性成分进行分析鉴定,用色谱峰面积归一化法计算各成分的相对含量。结果:从金门高粱酒中鉴定了14个化学成分,占总成分含量的98.95%,其中主要成分为酯类(76.90%)及醇类(15.71%)。结论:为阐明金门高粱酒的香型和风格提供了依据。     

气相色谱-质谱联用分析6种八角茴香油的化学成分

目的:通过气质联用分析比较6种不同八角茴香油的成分。方法:采用DB-1毛细管色谱柱(30 m×0.25 mm,0.25μm),程序升温。质谱条件:EI源,单四级杆质谱检测器分析,应用峰面积归一化法计算组分相对含量。结果:共检出43个化合物,鉴定了其中31个,反式茴香脑均是主要成分,但6种不同的八角茴香油成分存在一定差异。结论:6种八角茴香油质量存在差异。     

气相色谱-质谱法分析牛至中挥发油与脂肪酸成分

目的鉴定秦巴山区牛至中挥发油和脂肪酸成分。方法利用索氏提取法和水蒸气蒸馏法提取牛至中脂肪酸和挥发油成分,采用气相色谱 质谱（GC MS）联用技术分离鉴定。结果分别鉴定了脂肪酸中16 个化合物和挥发油中36 个化合物,并运用气相色谱峰面积归一化法确定相对百分含量。脂肪酸主要由亚油酸甲酯（27.40%）、异油酸甲酯（21.99%）和棕榈酸甲酯（10.63%）组成;挥发油中含量较高的是麝香草酚（27.28%）、十五烷（6.44%）、十八烷（5.53%）、2 甲基 5 （异丙基）苯酚（5.49%）、1-甲氧基-4-甲基-2-（1-异丙基）苯（3.18%）、十六烷（2.77%）、1-甲基-4-（5-甲基-1-亚甲基-4-己烯基） 环己烯（2.70%）。结论牛至脂肪酸和挥发油中含有多种有效活性组分。     

羚羊角中脂肪酸类成分的GC-MSD分析

目的：阐明羚羊角中脂肪酸类成分。方法：溶剂法提取脂类成分,经甲酯化,采用气相色谱一质谱．计算机联用技术分离鉴定,归一化法计算相对百分含量。结果：从羚羊角中鉴定出9种脂肪酸类成分,占总脂的85．14％,其中不饱和脂肪酸3种,占17．92％。结论：羚羊角中主要脂肪酸类成分为棕榈酸、硬脂酸、油酸,占80．31％。     

Oleate salt formation and mesomorphic behavior in the propranolol/oleic acid binary system.

Thermal analysis of propranolol/oleic acid mixtures prepared by solvent evaporation enabled construction of the binary system phase diagram. This allowed both physical and chemical interactions to be identified, including complex formation at the equimolar composition. An incongruent melting complex with a characteristic reaction point was identified in excess oleic acid compositions, a common property of fatty acid/fatty acid salt binary systems. The equimolar complex was confirmed to be propranolol oleate using infrared spectroscopy. Wide-angle X-ray powder diffractometry demonstrated that propranolol oleate possessed long-range positional order ( approximately 25 A d spacing) accompanied by a degree of disorder over shorter d spacings. Such a pattern suggested mesophase formation, explaining the unctuous nature of propranolol oleate at room temperature. Accurate measurement of the long-range d spacing was achieved using small-angle X-ray scattering, permitting differentiation of the three different phases identified (phase I: 25.4 A, phase II: 24.6 A, phase III: 25.4-25.5 A). The implications of drug fatty acid salt formation and also mesomorphism in pharmaceutical systems are discussed.     

鱼肝油中脂肪酸的气相色谱及气相色谱-质谱分析

目的 采用气相色谱法（GC）结合气相色谱-质谱（GC-MS）联用技术,对3种不同来源共26批鱼肝油样品中的脂肪酸成分进行测定。方法 通过氢氧化钾-甲醇碱催化法对鱼肝油样品进行甲基衍生化预处理,选用极性毛细管柱对样品中的衍生化产物脂肪酸甲酯进行分离,后经气相色谱仪-氢火焰离子化检测器（GC-FID）和气相色谱-质谱（GC-MS）联用仪进行分析检测。利用对照品定位法结合NIST谱库检索准确鉴定出棕榈酸、棕榈油酸、油酸、亚油酸、二十碳五烯酸（eicosapentaenoic acid,EPA）和二十二碳六烯酸（docosahexaenoic acid,DHA）等14种脂肪酸,并通过面积归一化法对这14种脂肪酸进行定量分析。结果 这14种脂肪酸在国内鱼肝油中的含量与模拟天然鱼肝油和进口鱼肝油样品中的含量存在较大差异。其中,EPA和DHA等脂肪酸在模拟天然鱼肝油和进口鱼肝油样品中的含量远高于其在国内鱼肝油样品中的含量,而亚油酸在国内鱼肝油样品中的含量却高达44%以上,10倍于其在另外2种鱼肝油样品中的含量。结论 不同来源的鱼肝油样品中的脂肪酸成分不尽相同,可根据脂肪酸的组成区别鱼肝油样品中是否添加天然鱼肝油成分。     

Absorption rate and bioavailability of valproic acid and its sodium salt from rectal dosage forms

Summary Rectal and oral absorption of valproic acid and its sodium salt by man were compared to explore the possibility of rectal administration of the drug. The plasma concentration of valproic acid was measured by gas chromatography after a single oral dose of sodium valproate 600 mg, and after single rectal doses of sodium valproate 600 mg and valproic acid 520 mg, in a cross-over study in 7 volunteers. The rectal dosage forms included fatty suppositories and aqueous solutions. Compared with oral administration, rectal absorption of sodium valproate from an aqueous micro-enema was fast and complete. The free acid was absorbed more rapidly from fatty suppositories than was the sodium salt. The absorption rate from the rectum increased with the dose of valproic acid. Both findings are consistent with a diffusion — absorption mechanism based on the pH-partition hypothesis. Differences in the chemical composition of the fatty suppository base were not reflected in differences in absorption rate and relative bioavailability. No essential difference in absorption rate was observed if volunteers remained lying or sitting during the experiment. Rectal dosing with valproic acid 520 mg dissolved in 4 ml suppositories, twice a day resulted in steady-state plasma concentrations of 50 to 100 µg · ml^–1, within the therapeutic range.Data have been presented in: F. Moolenaar, Ph. D. Thesis, Groningen, The Netherlands     

The mitigating effects of phosphatidylcholines on bile salt- and lysophosphatidylcholine-induced membrane damage.

The effects, at pH 7.0, of a series of 0.2 mM phosphatidylcholines (PC), namely dicaproyl-PC (DCPC), didecanoyl-PC (DDPC), dilauroyl-PC (DLaPC), dimyristoyl-PC (DMPC), dipalmitoyl-PC (DPPC), dioleoyl-PC (DOPC) and dilinoleoyl-PC (DLPC) and a series of 0.2 mM fatty acid salts (namely sodium myristate, palmitate, stearate, oleate and linoleate) upon the erythrocyte haemolysis induced by 2 mM sodium taurodeoxycholate (STDC) were determined. The influence of egg PC and dihexadecyl phosphate (DHDP) concentration upon the haemolysis induced by 1.4 mM sodium deoxycholate (SDC), 2 mM STDC and 0.1 mM lysophosphatidylcholine (LPC) were also established. A bile salt:egg PC mole ratio of 0.5 virtually abolished the haemolysis induced by SDC and STDC, whereas the same ratio of LPC:egg PC only reduced haemolysis from 65 to 40% (maximum haemolysis). DHDP had no effect on the haemolytic action of SDC or STDC. The salts of the fatty acids were non-haemolytic, and when mixed with STDC did not affect the level of haemolysis induced by the bile salt. In contrast, DDPC and DLaPC enhanced the haemolysis of STDC and DCPC had no effect, whereas DMPC, DPPC, DSPC, DOPC, DLPC and egg PC all reduced haemolysis. Maximum reduction was determined for DMPC and egg PC. The mixed micelle preparation temperature (either room or 60 degrees C) and temperature of incubation (either 20 degrees C for 30 min or 37 degrees C for 5 min) had only minor effects on the net haemolysis induced by STDC. These findings may be of significance in understanding the aetiology of certain gastrointestinal diseases and in determining whether mixed bile salt micelles have a role as drug penetration enhancers.     

Mechanism for the inducement of the intestinal absorption of poorly absorbed drugs by mixed micelles II. Effect of the incorporation of various lipids on the permeability of liposomal membranes

The mechanism for the enhancement of the intestinal absorption of drugs in the presence of mixed micelles was investigated using liposomal membranes as a biomembrane model. The effect of the incorporation of various lipids on the permeability of drugs through liposomal membranes was studied. Liposomes were prepared from egg phosphatidylcholine. Lipids used were fatty acids, glycerides, oleyl alcohol and methyl oleate, and drugs were phenol red, bromphenol blue, cefazolin, sulfanilic acid and procainamide ethobromide (PAEB). The absorption of these drugs in the large intestine was enhanced by the addition of monoolein—bile salt mixed micelles. The incorporation of monoolein into liposomal membranes markedly increased the release rate of these drugs through the membranes. Unsaturated fatty acids such as oleic acid and linoleic acid markedly enhanced the release rate of PAEB, while saturated fatty acids caused a small increase in the release rate. Diolein, triolein, oleyl alcohol, methyl oleate, oleic acid and linoleic acid had no enhancing effect on the release of phenol red. The effect of the treatment of liposomes with various solutions on the permeability of drugs through the membranes was investigated. Treatment solutions were a lipid—bile salt mixed micellar solution, a lipid-emulsion and a bile salt micellar solution. The treatment with a mixed micellar solution increased the release and the uptake of drugs. Temperature-dependent studies demonstrated that the incorporation of monoolein caused a decrease in the activation energy for the permeation process of phenol red through liposomal membranes from 17.5 to 14.3 kcal/mol.     

Covalent adduct formation and chloroform production after free radical attack on fatty acids by carbon tetrachloride reactive intermediates

The interactions of fatty acids and the trichloromethyl free radical generated anaerobically by the benzoyl peroxide model system were studied. Chloroform was produced due to the interaction of the trichloromethyl free radical with the unsaturated fatty acid ester methyl oleate, indicating the hydrogen in chloroform may result from abstraction from fatty acids. In addition, chloroform was detected in incubations containing the saturated fatty acid ester methyl stearate, indicating hydrogen abstraction is not limited to allylic hydrogens. Mass spectral analysis identified one adduct resulting from additional reactions to methyl oleate, and an adduct resulting initially from hydrogen abstraction on methyl stearate. These findings describe previously unreported reactions of the trichloromethyl free radical with saturated fatty acid, and inhibition of chloroform production by 3 free radical inhibitors.     

Mechanism for the inducement of the intestinal absorption of poorly absorbed drugs by mixed micelles I. Effects of various lipid—bile salt mixed micelles on the intestinal absorption of streptomycin in rat

The effects of various lipid—bile salt mixed micelles on the intestinal absorption of streptomycin were investigated using in situ closed-loop method in the rat. Lipids used were fatty acids, glycerides, oleyl alcohol and methyl oleate. Mixed micelles composed of monoolein or unsaturated fatty acids markedly enhanced the absorption of streptomycin in the large intestine. On the other hand, saturated fatty acids caused a small enhancement of the absorption. Triolein, diolein, oleyl alcohol and methyl oleate had no enhancing effect on the absorption.To clarify the difference in the enhancing effects of monoolein, unsaturated fatty acids and saturated fatty acids, the interaction of the drug with mixed micelles, the absorbability of lipids and the alteration of the mucosal membrane permeability induced by mixed micelles were investigated. The alteration of the mucosal membrane permeability was examined by an exsorption experiment. The difference in the enhancing effects was not attributed to the interaction or the absorbability of lipids, but a close correlation was found between the enhancing effects and the alteration of the mucosal membrane permeability. Monoolein or unsaturated fatty acids mixed micelles markedly increased the mucosal membrane permeability, while bile salt or saturated fatty acid mixed micelles caused small or no alteration of the permeability. The enhancement of the intestinal absorption by mixed micelles was mostly due to the alteration of the mucosal membrane permeability.     

Effects of vasopressin, angiotensin II and phenylephrine on hepatic ketogenesis and fatty acid synthesis

Studies were conducted to clarify the effects of vasopressin, angiotensin II and phenylephrine on hepatic ketogenesis and fatty acid synthesis. Hepatocytes from fed rats were incubated with oleate or octanoate. Vasopressin stimulated fatty acid synthesis as well as lactate and pyruvate accumulation in the presence of oleate. In accordance with this action, vasopressin caused a marked decrease in ketogenesis from oleate. When octanoate was added as a substrate, vasopressin failed to inhibit ketogenesis. Neither angiotensin II nor phenylephrine affected ketogenesis or fatty acid synthesis. The results in the present study show that there are vasopressin-mediated reciprocal changes in ketogenesis from oleate and fatty acid synthesis in isolated hepatocytes.     

Hyperthermic effect of palmitate sodium, stearate sodium and oleate sodium injected into the cerebral ventricles of conscious cats

Palmitate sodium, stearate sodium and oleate sodium injected into the cerebral ventricles of conscious cats produced hyperthermia. Threshold effects were obtained with as little as 2.0–5.0 μg of palmitate sodium and stearate sodium or 20.0 μg of oleate sodium. The hyperthermic effect of these fatty acids reached its maximum 2–3 hr after administration and lasted for more than 12 hr. The rise in temperature was always associated with sedation. The temperature was not affected by an i.p. injection of palmitate sodium (1.2–6.0 mg/kg), stéarate sodium (1.2–6.0 mg/kg) or oleate sodium (1.2–6.0 mg/kg).     

Effects of sodium 2-[5-(4-chlorophenyl)pentyl]-oxirane-2-carboxylate (POCA) on intermediary metabolism in isolated rat-liver cells

In hepatocytes isolated from meal-fed rats, sodium 2-[5-(4-chlorophenyl)pentyl]oxirane-2-carboxylate (POCA) decreased the rate of lipogenesis measured as incorporation of ³H from ³H₂O into glycerolipids and cholesterol. Moreover, POCA inhibited the oxidation of added oleate, whereas oleate esterification was stimulated. In hepatocytes from 24-hr-starved rats, inhibition of gluconeogenesis by POCA was observed only with gluconeogenic precursors which require pyruvate carboxylation. This inhibition was secondary to impaired oxidation of long-chain fatty acids by POCA. It is concluded that, in addition to its inhibition of long-chain fatty acid oxidation, POCA interferes with de novo synthesis of cholesterol and fatty acids. On the other hand, neither fatty acid esterification nor the conversion of oxaloacetate into glucose are affected by POCA.