Synthesis and isolation of epoxy secondary amidesvia direct amidation ofVernonia galamensis seed oil

Vernonia galamensis oil, containing naturally epoxidized triglycerides, was reacted withn-butylamine,n-pentylamine andn-hexylamine to afford high yields of epoxidized secondary amides. Three reaction conditions were investigated: (i) reflux with amines as solvents, (ii) reflux with hexane as the solvent and (iii) room temperature with the amines as solvents. Reactions with amines as refluxing solvents were completed in 1–5 h, while those with hexane went to completion within 2 to 5 d. Room temperature reactions were onlyca. 80% complete after several days. Reactivity was increased with higher amine homologs at both reflux and room temperature reaction conditions. Isolated yields of epoxy-containing amides were about 80% with purity exceeding 96% in all cases. Spectroscopic characterization of the previously unreported alkyl-vernolamides is provided.     

Synthesis of structured triglycerides from peanut oil with immobilized lipase

Structured triglycerides (ST) that contain medium- and long-chain fatty acids were synthesized by lipase-catalyzed interesterification between tricaprylin and peanut oil. To select appropriate enzymes, we investigated nine commercial lipase preparations for their ability to hydrolyze pure triglycerides as well as natural oils. Three microbial lipases from Rhizomucor miehei (RML), Candida sp. (CSL), and Chromobacterium viscosum (CVL) gave good results, and immobilized preparations were used in the interesterification. RML gave the highest yields of ST (73%, 40°C), although its hydrolytic activity toward triolein was low. As the temperature was raised to 50°C, the yield of ST increased to 79%. After 120 h reaction time, remaining activities were high for CSL (71%), moderate for CVL (48%), and low for RML (20%). Parts of this paper were presented as a poster at the Biochemical Engineering Conference IX, May 1995, Davos, Switzerland.     

Crystal morphology of mixtures of tripalmitin and butterfat

Blends of butterfat and tripalmitin are of interest for use as moisture barriers in edible films. Tripalmitin was blended with butterfat in the ratios 100:0, 90:10, 80:20, and so on through to 10:90 and 0:100. Crystal morphologies of squash and smear preparations were determined by polarizing light microscopy. Samples were stored at 19–22°C and re-examined after 6 d and after 30 d. Morphology was strongly dependent on composition and the presence of a coverslip. Morphology was less dependent on polymorphic form and age. Barrier properties depend more strongly on morphology than on polymorphic form.     

Comparison of pulsed NMR and ultrasonic velocity techniques for determining solid fat contents

An ultrasonic velocity technique has been compared with pulsed NMR'weight' and 'direct' methods of determining solid fat contents (SFC). Measurements were made at 18°C using samples 0–20% of rapidly cooled tristearin in paraffin oil, tristearin in sunflower oil and tripalmitin in paraffin oil. Correlations between the amount of triglyceride added and the SFC predicted by each of the techniques were always better than 0.995 ( n ± 13). The precisions of the ultrasonic technique (0.2%) and the weight method (0.3%) were significantly better than that of the direct method (0.7%). The ultrasonic technique may therefore offer a suitable alternative or adjunct to the established pulsed NMR technique for SFC determinations; it has considerably lower capital cost and a faster sampling rate.     

响应面法优化中碳链脂肪酸甘油三酯微胶囊制备配方的研究

中碳链脂肪酸甘油三酯具有降低体重、调节脂代谢、缓解疲劳等功效,其常温下为液态,为方便其在食品领域应用,以乳清蛋白、菊粉为壁材,采用喷雾干燥的方法制备中碳链脂肪酸甘油三酯微胶囊。通过单因素实验,考察复配壁材比例、壁材添加量、芯壁比、乳化剂添加量、复配乳化剂比例对中碳链脂肪酸甘油三酯微胶囊包埋率的影响,采用Box-Behnken设计响应面实验优化中碳链脂肪酸甘油三酯微胶囊的制备配方,并测定制备的中碳链脂肪酸甘油三酯微胶囊基本理化性质。结果表明：中碳链脂肪酸甘油三酯微胶囊最佳制备配方为乳清蛋白：菊粉3∶1(w/w)、乳化剂添加量0.4 g/100 mL、芯壁比1∶1(w/w)、复配壁材（乳清蛋白和菊粉）添加量14 g/100 mL、复配乳化剂（单甘酯∶羧甲基纤维素钠）1∶1(w/w),在此条件下制备的中碳链脂肪酸甘油三酯微胶囊包埋率可达95%,具有良好流动性、分散性及溶解性,粒径分布均匀,平均粒径为4.43μm。     

In Utero Exposure to Δ9-Tetrahydrocannabinol Leads to Postnatal Catch-Up Growth and Dysmetabolism in the Adult Rat Liver

The rates of gestational cannabis use have increased despite limited evidence for its safety in fetal life. Recent animal studies demonstrate that prenatal exposure to Δ9-tetrahydrocannabinol (Δ9-THC, the psychoactive component of cannabis) promotes intrauterine growth restriction (IUGR), culminating in postnatal metabolic deficits. Given IUGR is associated with impaired hepatic function, we hypothesized that Δ9-THC offspring would exhibit hepatic dyslipidemia. Pregnant Wistar rat dams received daily injections of vehicular control or 3 mg/kg Δ9-THC i.p. from embryonic day (E) 6.5 through E22. Exposure to Δ9-THC decreased the liver to body weight ratio at birth, followed by catch-up growth by three weeks of age. At six months, Δ9-THC-exposed male offspring exhibited increased visceral adiposity and higher hepatic triglycerides. This was instigated by augmented expression of enzymes involved in triglyceride synthesis (ACCα, SCD, FABP1, and DGAT2) at three weeks. Furthermore, the expression of hepatic DGAT1/DGAT2 was sustained at six months, concomitant with mitochondrial dysfunction (i.e., elevated p66shc) and oxidative stress. Interestingly, decreases in miR-203a-3p and miR-29a/b/c, both implicated in dyslipidemia, were also observed in these Δ9-THC-exposed offspring. Collectively, these findings indicate that prenatal Δ9-THC exposure results in long-term dyslipidemia associated with enhanced hepatic lipogenesis. This is attributed by mitochondrial dysfunction and epigenetic mechanisms.     

甲醇钠催化酯交换制备中/长链结构甘三酯

以中碳链链甘三醋和大豆油为原料,以甲醉钠为催化剂催化醋交换反应合成中/长链结构甘三酯.研究了反应温度、反应时间和甲醇钠添加童3个因素对酯交换反应的影响.结果表明,反应温度50℃,反应时间20min,甲醉钠添加童(以油质童计)0.3%时酯交换反应达到最佳状态,产物中中/长链结构甘三酯的含童为75.29%.通过正交极差分析得出,甲醉钠添加量是影响酯交换反应的主要因素,其次是反应温度,反应时间的影响较小.     

响应面分析法优化中链甘油三酯微胶囊的制备

为优化以麦芽糊精为壁材制备中链甘油三酯微胶囊的工艺条件,在单因素试验的基础上,选取芯材与壁材质量比、乳化剂用量、乳状液固形物质量分数为自变量,微胶囊化效率为响应值,根据Box-Benhnken中心组合试验设计原理采用三因素三水平的响应面试验,依据回归分析确定最佳制备条件.结果表明,中链甘油三酯微胶囊最佳制备条件为:芯材与壁材质量比3.56:6.44,乳化剂用量3.59%,乳状液固形物质量分数27.6%.在此条件下微胶囊化效率预测值为96.58%,验证值为96.53%.     

Upgrading the AOCS infrared trans method for analysis of neat fats and oils by fourier transform infrared spectroscopy

An automated protocol for the direct, rapid determination of isolated trans content of neat fats and oils by Fourier transform infrared (FTIR) spectroscopy was devised, based on a simple modification of the standard AOCS trans method, eliminating the use of CS₂ and methylation of low trans samples. Through the use of a commercially available, heated transmission flow cell, designed specifically for the analysis of neat fats and oils, a calibration (0–50%) was devised with trielaidin spiked into a certified, trans-free soybean oil. The single-beam spectra of the calibration standards were ratioed against the single-beam spectrum of the base oil, eliminating the spectral interference caused by underlying triglyceride absorptions, facilitating direct peak height measurements as per the AOCS IR trans method. The spectrometer was preprogrammed in Visual Basic to carry out all spectral manipulations, measurements, and calculations to produce trans results directly as well as to provide the operator with a simple interface to work from. The derived calibration was incorporated into the software package, obviating the need for further calibration because the program includes an automatic recalibration/standardization routine that automatically compensates for differences in optical characteristics between instruments, instrument drift over time, and cell wear. The modified AOCS FTIR analytical package was evaluated with Smalley check samples for repeatability, reproducibility, and accuracy, producing SD of ± 0.07, 0.13, and 0.70 trans, respectively, the FTIR predictions being linearly related to the Smalley means (r=0.999; SD=± 0.46), and well within one SD of the Smalley sample means. Calibration transfer was assessed by implementing the calibration on a second instrument and reanalyzing the Smalley check samples in cells of two different pathlengths (25- and 50-μm). There were no statistically significant differences between the FTIR trans predictions obtained for the Smalley samples from the two instruments and two cells, indicating that the software was able to adjust the calibrations to compensate for differences in instrument response and cell pathlength. The FTIR isolated trans analysis protocol developed by the McGill IR Group has the benefit of being based on the principles of an AOCS-approved method, matches its accuracy, and allows the analysis to be performed on both neat fats and oils, producing trans predictions in less than 2 min per sample. It is suggested that this integrated approach to trans analysis, which requires a minimum level of sample manipulation and operator skill, be considered as a modification of the proposed Recommended Practice CD14b-95.     

High-performance liquid chromatography of the triacylglycerols ofVernonia galamensis andCrepis alpina seed oils

The triacylglycerols ofVernonia galamensis andCrepis alpina seed oils were characterized because these oils have high concentrations of vernolic (cis-12,13-epoxy-cis-9-octadecenoic) and crepenynic (cis-9-octadecen-12-ynoic) acids, respectively. The triacylglycerols were separated from other components of crude oils by solid-phase extraction, followed by resolution and quantitation of the individual triacylglycerols by reversed-phase high-performance liquid chromatography with an acetonitrile/methylene chloride gradient and flame-ionization detection. Isolated triacylglycerols were characterized by proton and carbon nuclear magnetic resonance and by capillary gas chromatography of their fatty acid methyl esters. The locations of the fatty acids on the glycerol moieties in the oils were obtained by lipolysis. TheVernonia galamensis oil contained 50% trivernoloyl and 21% divernoloyllinoleoyl glycerols along with 20% triacylglycerols with one vernolic and two other fatty acids. TheCrepis alpina oil contained 36% tricrepenynoyl and 33% dicrepenynoyllinoleoyl glycerols, 17% triacylglycerols with two crepenynic and one other fatty acid and 7% triacylglycerols with one crepenynic acid and two other fatty acids. Vernolic acid was found at both the 1(3)- and 2-glycerol carbons but was more abundant at the 1,(3)-position in theVernonia galamensis oil. Crepenynic acid was found at both glycerol carbon positions but was more abundant at the 2-position in theCrepis alpina oil. Visiting scientist from Technical Research Institute, Snow Brand Milk Company, Ltd., Saitana, Japan.