Gram-scale chromatographic purification of beta-sitosterol. Synthesis and characterization of beta-sitosterol oxides

An effective purification method for beta-sitosterol was developed starting from a commercial source of a phytosterol mixture using preparative adsorption column chromatography. beta-Sitosterol (> or = 95% purity) was obtained on a gram-scale. Thus, the synthesis of six beta-sitosterol oxides, including 7alpha-hydroxy, 7beta-hydroxy, 5,6alpha-epoxy, 5,6beta-epoxy, 7-keto, and 5alpha,6beta-dihydroxysitosterol, were successfully carried out. The spectral characteristics of all the synthetic intermediates and target compounds (approximately 95% purity) were well-documented.     

Determination of thermo-oxidation products of plant sterols

Plant sterols are subjected to oxidation when exposed to air and, especially, when heated at high temperatures. We developed a method to study thermo-oxidation of plant sterols. The method consisted of cold saponification, purification of oxides by solid-phase extraction and gas chromatography analysis. To compensate for losses during the procedure, an internal standard was added before saponification. The method showed good recovery of added cholesterol oxides, separation of plant sterol oxides and reproducibility in detecting thermo-oxidation products of stigmasterol and rapeseed oil. Based on this study, the major products are 7-hydroxy, 5,6-epoxy and 7-keto compounds and oxides are formed faster in bulk stigmasterol than in rapeseed oil.     

Process optimization for extraction of carotenoids from shrimp waste with vegetable oils

Shrimp waste is an important source of natural carotenoid. Studies were carried out to determine the extraction yield of shrimp waste carotenoids in different vegetable oils. Highest yield was obtained by extraction using refined sunflower oil compared to groundnut oil, gingelly oil, mustard oil, soy oil, coconut oil and rice bran oil. The extraction yield of carotenoids in sunflower oil was significantly influenced by level of oil to waste (p < 0.05), time (p < 0.01) and temperature (p < 0.001) of heating waste with oil before centrifugation to separate pigmented oil. A regression equation was derived for carotenoid yield as a function of time of heating, temperature of heating and oil level to waste. The optimized conditions for extraction of shrimp waste carotenoids in sunflower oil were determined to be oil level to waste of 2, temperature of 70 degrees C and heating time of 150 min.     

α-亚麻酸甾醇酯的理化特性及氧化稳定性研究

本文研究了采用无溶剂直接酯化法合成得到的α-亚麻酸甾醇酯的理化特性、脂溶性、结晶特性、油脂氧化稳定性。结果表明,α-亚麻酸甾醇酯具有理想的理化特性,酸价和过氧化值分别为1.2 mg KOH/g和0.56meq/kg,反式脂肪酸含量小于0.1%,在不同植物油脂中的溶解性达到30%以上,结晶温度区间在-25.9～-29.6℃之间。α-亚麻酸甾醇酯在大豆油、油菜籽油和亚麻籽油中的浓度分别小于0.1%、0.1%和0.3%,油脂的氧化诱导时间随浓度增加而增加。因此α-亚麻酸甾醇酯良好的理化特性表明其在不同形态食品、保健品和医药产品等中将具有较广的应用范围,是一种具有较高营养价值的功能性食品添加剂。     

An improved method to discover adulteration of Styrian pumpkin seed oil

Pumpkin seed oil is rather expensive compared to other vegetable oils. Therefore, it is often adulterated by the addition of cheaper oils. In contrast to other edible oils, the content of Delta 5-sterols is very low, while Delta 7-sterols are dominating. The determination of Delta 5-sterols, especially beta-sitosterol has proven to be a good possibility to detect admixture of cheap vegetable oils to a level below which the economic profit is not significant any more. The presented method is a variant of an analysis concept, which has been published previously in European Food Research and Technology by Mandl et al. [Eur. Food Res. Technol. 209 (1999) 400. ]. It includes saponification of the triglycerides as a first step followed by separation of the potassium salts of the fatty acids from the unsaponifiable fraction by adsorption chromatography. In order to enhance gas chromatographic properties of the analytes, the hydroxyl function of the sterols is derivatized with N-Methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) to the trimethylsilylether. Finally, the analytes are separated on a capillary column of medium polarity (HP 35 MS) in a temperature programmed run within 18 min. Detection of the analytes was done by flame ionization. Special attention was set onto the precision and repeatability of the method.     

Characteristics and composition of Parkia biglobbossa and Jatropha curcas oils and cakes

Parkia biglobbossa (PKBS) and Jatropha curcas (JTC) seeds were analysed for their proximate composition. The seeds oils were analysed for fatty acid, lipid classes, sterols and physicochemical characteristics. Proximate analysis revealed that the percentage crude protein, crude fat and moisture in PKBS were 32.40%, 26.525% and 10.18% respectively and 24.60%, 47.25% and 5.54% in JTC. Campesterol, stigmasterol, beta-sitosterol, Delta5-avenasterol and Delta7-stigmasterol were identified in the seed oils, but beta-sitosterol was most abundant, constituting 71.9% in JTC and 39.5% in PKBS. JTC oil had 72.7% unsaturated fatty acids with oleic acid predominating, while PKBS had 62% unsaturated fatty acids with linoleic acid being the most abundant. Results of lipid classes showed triglyceride as the dominant lipid species in the seed oils. Physicochemical analysis of the seed oils showed that they could be classified as semi drying oils and that they could be found applicable in alkyd resin and soap manufacture.     

Direct extraction of astaxanthin from <Emphasis Type="Italic">Haematococcus</Emphasis> culture using vegetable oils

A green, downstream process using common vegetable oils was used for the direct extraction of astaxanthin from Haematococcus. The process consists of a single integrated unit to extract astaxanthin with subsequent separation of the astaxanthin-containing oil extract. Without a cell harvest process step, the culture broth was directly mixed with the vegetable oils; the astaxanthin inside the cell was extracted into the vegetable oil phase by hydrophobic interactions, with recovery yields of 88% and above. The oil extracts were simply separated from the culture medium containing cell debris by gravity settling only.     

Triacylglycerols composition, oxidation and oxidation compounds in camellia oil using liquid chromatography-mass spectrometry

Camellia seed oil is one of most important edible oil, rich in oleic acid and contains many natural antioxidants with various biological activities. During preparation of foods or storage camellia oil oxidizes by the auto-oxidation and produce oxidized compounds. Traditional analytical techniques like FFA, POV are used for the determination of oxidation and adulteration of oils and fats. These methods were rarely able to detect the oxidized compounds produced and extent of oxidation. This paper presents the uses of liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) for the analysis of triacylglycerols (TAGs) composition and evaluation of auto-oxidation and oxidation products of camellia seed oil. The camellia oil was auto-oxidized for 12 months at room temperature. The TAGs were identified from their characteristics fragmentations such as protonated molecular ion, ammonium and sodium adducts, diacylglycerols, epoxy-diacylglycerols fragments and mono-acylglycerol fragments in ESI-MS mass spectra. HPLC-ESI-MS data revealed the separation and identification of 15 TAGs. The major TAGs separated and identified in camellia seed oil were POO, OOO, OLO, PLO/POL, OLL, SOO, ALO and OLLn. The auto-oxidation studies revealed a total loss of LnLLn, LnOLn, LLLn and OLLn amounting about 13.5% total oxidation. The auto-oxidation products were epoxy hydroperoxides, epoxy epidioxides, and mono-epoxides. It was observed that these were characteristic compounds produced in high oleic oils.     

Notes on the Biology and Uses of the Motacú Palm(Attalea phalerata,Arecaceae) from Bolivia

The motacú palm (Attalea phalerata) is widespread in Bolivia and is an economically valuable species as a source of vegetable oil. In Bolivia it is utilized as construction material, food, medicine, cosmetic, and edible oil. Oil extracted from the kernel (60–70% of dry weight) is high in lauric and myristic oils and compares favorably with other tropical oil crops. The palms reach reproductive maturity in 7–10 years and potential oil production from cultivated stands is 1.1-2.4 tons/ha/yr.     

小花清风藤挥发油化学成分研究

利用水蒸气蒸馏法提取小花清风藤中的挥发性成分,通过气相色谱质谱联用技术（GC-MS）并结合计算机分析鉴定提取物中挥发油芳香成分,共鉴定出17种化合物,其中有12种烷烃类化合物,1种芳香类化合物,1种醚类化合物,1种杂环类化合物,1种环戊二烯和1种酰胺类化合物。用面积归一化法测定挥发油中各种成分的相对含量,合计占总峰面积的8.8%。实验结果表明：用水蒸气蒸馏提取小花清风藤挥发油时,提取率为4.18%,其最主要成分为烷烃类化合物。     

Stability of CoQ10-Loaded Oil-in-Water (O/W) Emulsion: Effect of Carrier Oil and Emulsifier Type

Co-enzyme Q10 (CoQ10), a lipophilic compound that widely used in the food and pharmaceutical products was formulated in a κ-carrageenan coated oil-in-water (O/W) emulsion. In this work, we examined the solubility of CoQ10 in different carrier oils and effects of emulsifier type on the formation and stability of CoQ10-loaded O/W emulsion. Nine vegetable oils and four types of emulsifiers were used. CoQ10 was found significantly (p?<?0.05) more soluble in medium chain oils (coconut oil and palm kernel oil) as compared to other vegetable oils. The O/W emulsions were then prepared with 10 % (w/w) coconut oil and palm kernel oil containing 200 g CoQ10/L oil stabilized by 1 % (w/v) emulsifiers (sucrose laurate (SEL), sodium stearoyl lactate (SSL), polyglycerol ester (PE), or Tween 80 (Tw 80)) in 1 % (w/v) κ-carrageenan aqueous solution. Particle size distribution and physical stability of the emulsions were monitored. The droplet sizes (surface weighted mean diameter, D[3,2]) of fresh O/W emulsion in the range of 2.79 to 5.83 μm were observed. Irrespective of the oil used, results indicated that complexes of SSL/κ-carrageenan provided the most stable CoQ10-loaded O/W emulsion with smaller and narrower particle size distribution. Both macroscopic and microscopic observations showed that O/W emulsion stabilized by SSL/κ-carrageenan is the only emulsion that exhibited no sign of coalescence, flocculation, and phase separation throughout the storage period observed.     

Studies on cottonseed oil biodiesel prepared in non-catalytic SCF conditions

The vegetable oils are all extremely viscous with viscosities ranging from 10 to 20 times greater than petroleum diesel fuel. The purpose of the transesterification process is to lower the viscosity of the oil. Methyl and ethyl esters as biodiesel were prepared from cottonseed oil through transesterification using non-catalytic supercritical fluids. The transesterfication of linseed oil in SCF such as methanol and ethanol has proved to be the most promising process. The biodiesels were characterized for their physical and main fuel properties including viscosity, density, flash point and higher heating value (HHV). The viscosities of biodiesels (3.6-4.0 mm(2)/s at 311 K) were much less than those of pure oils (33-36 mm(2)/s at 311 K), and their HHVs of approximately 40.5 MJ/kg were 10% less than those of petrodiesel fuels (approximately 45 MJ/kg). The flash point values (435-445 K) of methyl and ethyl esters are highly lower than that of cottonseed oil (507-512 K). The most important variables affecting the ester yield during the transesterification reaction are molar ratio of alcohol to vegetable oil and reaction temperature.     

Canola,corn, and vegetable oils as alternatives for wheat germ oil in fruit fly larval diets

Four wheat germ oil alternatives (corn oil, vegetable oil, canola oil with 10% vitamin E, and canola oil with 20% vitamin E), purchased from a local supermarket in Hawaii, were added to a fruit fly liquid larval diet as a replacement for wheat germ oil in the rearing of fruit fly larvae. The oils were tested on three species of fruit flies in Hawaii, Ceratitis capitata (TSL strain), Bactrocera dorsalis, and Bactrocera cucurbitae. They were evaluated for their efficacy in replacing WGO, based on: pupal recovery (%), larval duration (d), pupal weight (mg), adult emergence (%), adult fliers (%), mating (%), egg production per female per day, egg hatch (%), and peak egging period (d). Diets with WGO and without any oil were used as controls. The objective of the study was to select the most cost effective alternative oils with the best performance to replace the currently used WGO, which is pricey and hard to find. The results showed that there was no significant difference in performance among the tested oils in B. cucurbitae and B. dorsalis as regards the above mentioned parameters. Lower mating rate was observed in B. cucurbitae from those reared in vegetable oil and canola oil (10% vitamin E) diet. Lower egg production and egg hatch were obtained with B. dorsalis whose larvae were reared in vegetable and canola oil (both 10% and 20% vitamin E). Vegetable oil diet seemed to reduce pupal weight, shorten larval duration, and increase pupal recovery of C. capitata. The results suggest that WGO can be substituted with corn oil, vegetable oil, or canola oils for B. cucurbitae, while corn oil is a better alternative for B. dorsalis, and vegetable oil is best for C. capitata.     

The hard choice for alternative biofuels to diesel in Brazil

This paper selects biofuel scenarios to substitute diesel in Brazil based on oil reserves increase, diesel imports, CO₂ emissions, crops agronomic yields, byproducts marketing and social impacts. This hard task still considers that agricultural practices in developing countries have large social impacts. Brazil presents high consumption of diesel oil in transport; low agronomic yield of traditional vegetable oil crops, which demand large cultivation areas contrasting with microalgae and palm oils which present high productivity. Concerning technologies, thermal cracking and transesterification of vegetable oils present a difficult economic situation related to vegetable oils price, food competition and glycerin market; BTL technology, meaning thermal gasification of biomass to liquids, faces problems related to low density of biomaterials and low viscosity of synthetic biodiesel produced. Biorefinery algal integrated systems and co-solvent technology to introduce up to 8% of ethanol into diesel seem to be feasible routes to reduce diesel consumption.     

Laurie oil resources

Lauric oils and their derivatives have many applications both in the food and chemical industries. The major sources and some alternative raw materials for this multi-billon dollar business are discussed in the light of their ability to supply future market needs. There should be ample supply of lauric oils—except when drought and possibly disease affect large areas of coconut plantations—because of the rapid increase in palm kernel oil production expected from the African oil palm during the next decade. Most other sources are unlikely to be important in the short term because of the generally adequate supply of lauric oils and the considerable amount of research still needed to convert the best options into viable crops. However, a dramatic effect on supply can be expected if it becomes possible to manipulate the appropriate genes from lauric oil producing species of Cuphea into a conventional oil crop like rape. Future demand for lauric oils will be affected by the relative price of other vegetable oils and petroleum feedstocks that can be used to replace them in the manufacture of an increasing number of end products in both the food and chemical industries.     

Preference for vegetable oils in the two-bottle choice test in mice

We evaluated in mice their preference for different vegetable oils using the two-bottle choice test. Mice showed preference for all vegetable oils (at 1% concentration in emulsion) tested, including corn oil, canola oil, and mixed vegetable oil, compared to a control fluid without oil. Mice also significantly preferred highly palatable sucrose solutions (5-20%) in this test. One percent corn oil was selected to the same extent as were these sucrose solutions. Mixtures of 1% corn oil and several concentrations of sucrose were preferentially selected as compared to corn oil or sucrose alone. The concentration-response curves of oil-sucrose mixtures vs sucrose (0.5-20% concentrations) were similar to those of sucrose vs control solutions. These results suggest that 1% corn oil and sucrose at the concentrations tested did not affect each other's preference. Chronic intake of 20% sucrose solution, but not 100% corn oil, changed the preference for lower concentrations of each, and both induced remarkable increases in body weight of mice. In conclusion, we showed that mice preferred vegetable oils, and this preference compared favorably with highly palatable sucrose solutions and was not changed by chronic intake of corn oil.     

Effects of oxidation on the hydrolysis by cholesterol esterase of sitosteryl esters as compared to a cholesteryl ester

Phytosteryl esters (PE) are used as ingredients in functional food to decrease plasma concentration of low density lipoprotein-cholesterol (LDL-C). Effective impairment of cholesterol absorption by PE suggests that these esters are hydrolyzed by the pancreatic cholesterol esterase (CEase, EC 3.1.1.13) and the liberated sterol may interfere with cholesterol reducing its intestinal absorption. PE-enriched foods are marketed for cooking purposes, and temperature is one of the most important factors leading to the formation of oxidation products. Very little is known about the outcome of PE oxides during the digestive process. A new analytical method based on mass spectrometric detection directly after enzymatic reaction was developed to determine in vitro the activity of CEase on PE and their oxides present in functional food. Using this method, we identified a new inhibitor of CEase: sitosteryl 9,10-dihydroxystearate, which behaves as a non-competitive inhibitor of the hydrolysis of cholesteryl oleate and sitosteryl oleate.     

Effects of oxidation on the hydrolysis by cholesterol esterase of sitosteryl esters as compared to a cholesteryl ester

Phytosteryl esters (PE) are used as ingredients in functional food to decrease plasma concentration of low density lipoprotein-cholesterol (LDL-C). Effective impairment of cholesterol absorption by PE suggests that these esters are hydrolyzed by the pancreatic cholesterol esterase (CEase, EC 3.1.1.13) and the liberated sterol may interfere with cholesterol reducing its intestinal absorption. PE-enriched foods are marketed for cooking purposes, and temperature is one of the most important factors leading to the formation of oxidation products. Very little is known about the outcome of PE oxides during the digestive process. A new analytical method based on mass spectrometric detection directly after enzymatic reaction was developed to determine in vitro the activity of CEase on PE and their oxides present in functional food. Using this method, we identified a new inhibitor of CEase: sitosteryl 9,10-dihydroxystearate, which behaves as a non-competitive inhibitor of the hydrolysis of cholesteryl oleate and sitosteryl oleate.