Selectivity of lipases: isolation of fatty acids from castor,coriander, and meadowfoam oils

The lipase‐catalyzed hydrolysis of castor, coriander, and meadowfoam oils was studied in a two‐phase water/oil system. The lipases from Candida rugosa and Pseudomonas cepacia released all fatty acids from the triglycerides randomly, with the exception of castor oil. In the latter case, the P. cepacia lipase discriminated against ricinoleic acid. The lipase from Geotrichum candidum discriminated against unsaturated acids having the double bond located at the Δ‐6 (petroselinic acid in coriander oil) and Δ‐5 (meadowfoam oil) position or with a hydroxy substituent (ricinoleic acid). The expression of the selectivities of the G. candidum lipase was most pronounced in lipase‐catalyzed esterification reactions, which was exploited as part of a two‐step process to prepare highly concentrated fractions of the acids. In the first step the oils were hydrolyzed to their respective free fatty acids, in the second step a selective lipase was used to catalyze esterification of the acids with 1‐butanol. This resulted in an enrichment of the targeted acids to approximately 95—98% in the unesterified acid fractions compared to the 70—90% content in the starting acid fractions.     

Rigid urethane foams from blown castor oils

Solvent-blown rigid urethane foams prepared from a low-cost polyol mixture composed of raw castor oil and triisopropanolamine have been described. Foams with higher compressive strengths can be obtained by substituting oxidized (blown) castor oil for the raw castor oil in formulations of this type. The properties of rigid foams prepared from several commercial blown castor oils are described. The properties of these foams are correlated with the degree of oxidation of the blown oils used, as indicated by their oxygen content, density, viscosity, and refractive index. Removal of acid from blown oils having high acid values has no significant effect on the compressive strength of foams prepared from these oils. When blown castor oil is used instead of raw castor oil, less isocyanate is required to produce a urethane foam of specified density and compressive strength. Presented at the AOCS meeting in Toronto, Canada, 1962. A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Preparation of Acetoxy-Epoxy Derivatives of Vegetable Oils as Potential PVC Plasticizers and Stabilizers

Various acetoxy and epoxy derivatives of castor, safflower and linseed oils individually and in blends were prepared. Castor oil, two mixtures of castor and safflower oils (1 : 1 and 1 : 2, v/v) and two mixtures of castor and linseed oils (1 : 1 and 1 : 3, v/v) were first acetylated and then epoxidised by the comparatively best epoxidation method, i.e. in situ epoxidation technique using 60% hydrogen peroxide and the acid-form of Amberlite-120 resin (C. G.) as catalyst. Linseed oil was partially epoxidised to different products having various degrees of residual unsaturation, namely I. V. 98.3, 120.8 and 145.5. The partially epoxidised products were hydrogenated to yield unsaturated hydroxy compounds, protecting the unsaturation by cupric nitrate, and, the resulting unsaturated hydroxy glycerides were acetylated and further epoxidised by the in situ epoxidation method. Thus, various glycerides with varying ratios of acetoxy and epoxy groups were prepared and characterised for the use as stabilizers and plasticizers for PVC resins.     

新型碱性离子液体催化蓖麻油制备生物柴油

合成了新型碱性离子液体[Bmim]OH,将其应用于催化蓖麻油制备生物柴油,并与催化剂KOH、四丁基氢氧化铵进行比较,结果好于后两者。正交实验优化的碱性离子液体[Bmim]OH催化工艺条件为:催化剂用量为1%,醇油摩尔比为6∶1,反应温度为40℃,反应时间为60 min。在该优化条件下,甲酯混合物收率高于97%,蓖麻油基本上完全转化,其中高于95%转化为产物甲酯,催化剂[Bmim]OH重复使用6次没有明显消耗,催化性能稳定。     

Ethanolysis of castor and cottonseed oil: A systematic study using classical catalysts

Several classical catalytic systems for the transesterification reaction have been used to produce FA ethyl esters (FAEE) from castor and cottonseed oils The effects of the amount and nature of the catalyst, and of the reaction temperature, on the yields of FAEE were determined. The most efficient transesterification of castor oil was achieved in the presence of methoxide and acid catalysts, whereas for cottonseed oil, which has a composition that is much more similar to most vegetable oils than is castor oil, the highest yields of FAEE were obtained following base-catalysed ethanolysis.     

Microwave-assisted solvent extraction of castor oil from castor seeds

This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction (MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed (S/F, ml of solvent to gram of feed) ratios. The process parameters were optimized by statistical approach using historical data design of response surface method (RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.     

Some physical properties and oxidative stability of biodiesel produced from oil seed crops

Biodiesel is a cleaner burning fuel than petrodiesel and a suitable replacement in diesel engine. It is produced from renewable sources such as vegetable oils or animal fats. Biodiesel fuel was prepared from castor (CSO), palm kernel (PKO) and groundnut (GNO) oils through alkali transesterification reaction. The biodiesel produced was characterized as alternative diesel fuel. Fuel properties such as specific gravity, viscosity, calorific (combustion) value, The CSO, PKO and GNO were measured to evaluate the storage/oxidative stability of the oils to compare them with commercial petrodiesel. The biodiesel produced had good fuel properties with respect to ASTM D 6751 and EN 14214 specification standards, except that the kinematic viscosity of castor oil biodiesel was too low. The viscosity of castor oil biodiesel at different temperatures was in the range of 4.12–7.21 mm²/s. However, promising results which conformed to the above specification standards were realized when castor oil biodiesel was blended with commercial petrodiesel. At 28 °C the specific gravity recorded for CSO, PKO and GNO biodiesel was higher than the values obtained for petrodiesel. Commercial petrodiesel had the highest oxidative stability than biodiesel produced from CSO, PKO and GNO oils.     

Urethane polymers from hydroxylated fish oil

Alewife fish oil was hydroxylated by performic, peracetic and pertungstic acid methods. Products were compared with respect to yield, free acid, hydroxyl number, saponification value and peroxide value. Fish oils oxidized with performic acid resulted in high yields (83% to 95%), low acid values (0.12 to 0.19), high hydroxy (142 to 245) and saponification (247 to 271) numbers, and relatively low peroxide values (72 to 266). Performic acid hydroxylated alewife and menhaden oils were used to prepare urethane foams. These foams exhibited characteristic low compressive strengths at 10% deflection (6.4 to 9.5 psi), low density (1.45 to 1.65 pcf), high porosity (0.7 to 1.7% closed cells) and high water absorption compared to a conventional polyether urethane foam. Performic acid hydroxylated alewife oil was further refined, using cation and anion exchange resins, for use in the preparation of urethane elastomers. These polymers generally exhibited higher tensile and Graves tear strengths than a comparable castor oil elastomer used as a control. though dielectric strengths were similar for both fish oil and castor oil elastomers, tensile elongation at break point was greater for the castor oil elastomers. When the isocyanate index of the fish oil elastomers was increased from 105 to 156, the Graves tear strength exhibited the greatest change.     

Triterpene alcohols and sterols of vegetable oils

Triterpene alcohols and sterols were separated by thin-layer chromatography and gas-liquid chromatography from the unsaponifiable fractions of the following 18 vegetable oils: linseed, peanut, olive, rice bran, palm kernel, corn, sesame, oiticica, palm, coconut, rapeseed, grape seed, sunflower, poppy seed, castor, tea seed, cocoa butter and soybean. Two triterpene alcohols, cycloartenol and 24-methylene cycloartanol, were found in all of the oils except soybean oil, which contained only cycloartenol. Triterpene alcohols such as α- and β-amyrin, euphorbol, butyrospermol and cyclolaudenol also were encountered occasionally. Three sterols, β-sitosterol, stigmasterol and campesterol were present in all of the oils. In addition a fourth sterol, not yet idenfified, was found in oils of palm, palm kernel and sunflower in varying amounts. This unknown sterol and brassicasterol were found in rapeseed oil in addition to the three sterols that were common to all of the oils studied. Experiment Station for Fats and Oils, National Center for Lipochemistry of National Research Council, Milan, Italy.     

蓖麻油的单官能团反应

蓖麻油是具有独特性能的植物油类,分子中含有羟基、酯基、烯键等官能团,这些官能团可以单独进行反应得到蓖麻油衍生物,也可以其中两个或三个基团组合先后进行不同反应得到特殊用途的蓖麻油衍生物。主要对三种官能团单独进行化学反应综述归类,系统地介绍蓖麻油中各官能团所能发生的反应,简述不同反应产物的用途,较全面地介绍了蓖麻油基础化学反应知识,便于新反应和多官能团反应的设计和新产品的开发,提高蓖麻油深加工技术水平。     

Chromatographie analysis of seed oils. Fatty acid composition of castor oil

The fatty acid composition of a number of domestic and foreign castor oils was determined by consecutive column and gas-liquid Chromatographic analysis. After saponification of the oils and removal of the unsaponifiables, the nonhydroxy, monohydroxy, and dihydroxy acids were fractionated by partition chromatography on silicic acid. The amount of acid in each fraction was determined by titration or weighing. Gravimetric data were in good agreement with the titrimetric data. The acids obtained by saponification were converted to methyl esters with diazomethane and similarly subjected to partition chromatography. The methyl esters from various fractions were analyzed by gas-liquid chromatography. Components were tentatively identified by their comparative retention times and confirmed Presented at the AOCS meeting in Chicago, 1961. A laboratory of the Western. Utilization Research and Development Division, Agricultural Research Service, U.S.D.A.     

Fatty Acid Estolides: A Review

Estolides are bio-based oils synthesized from fatty acids or from the reaction of fatty acids with vegetable oils. Estolides have many advantages as lubricant base oils, including excellent biodegradability and cold flow properties. Promising applications for estolides include bio-lubricant base oils and in cosmetics. In this review, the synthesis of estolides from fatty acids using four different types of catalysts, namely, mineral acids, solid acids, lipases, and ionic liquids, is summarized. The summary includes the yield of estolide obtained from varying synthetic conditions (time, temperature, catalyst). Also reviewed are studies comparing the physical properties of estolides synthesized from refined fatty acids against those synthesized from fatty acid mixtures obtained from vegetable oils such as coconut, castor, Physaria, etc. By varying the structure of the fatty acids, estolides with a wide range of pour point, cloud point, and viscosity are synthesized to meet a wide range of application requirements. Currently, estolide products are being commercialized for personal care and lubricant base oils for automotive, industrial, and marine applications. The application areas and the demand for estolides is expected to grow as the drive for switching from petroleum to bio-based products keeps growing.     

Cinnamoyl esters of lesquerella and castor oil: Novel sunscreen active ingredients

Lesquerella and castor oils were esterified with cinnamic acid (CA) and 4-methoxycinnamic acid (MCA). Esterification of the hydroxy oils reached 85% completion with CA and 50% conversion with MCA. The hydroxy oils were esterified at 200°C under a nitrogen atmosphere within a sealed system. Unreacted CA and MCA were removed from the reaction mixtures by sublimation at 100°C under vacuum. The resultant methoxycinnamic oils possessed a broader, more blue-shifted UV absorbance, 250 to 345 nm with a λ_max of 305 nm, compared with the cinnamic oils, which absorbed from 260 to 315 nm, λ_max of 270 nm. The methoxycinnamic oils provide better UV-B absorption and thus are better candidates to be used as sunscreen active ingredients. Esterifications of the hydroxy oils with MCA at 200°C resulted in conversion of 40% of the MCA to undesirable by-products. Esterifications with MCA performed at 175°C in the presence of a tin catalyst resulted in similar percent conversions to product without degradation of MCA. Esterifications of lesquerella oil with MCA at 175°C resulted in higher conversions, 43%, than analogous esterifications with castor oil, 29%. The hydroxyl groups of the lesquerella and castor oils provide their excellent emolliency, lubricity, and noncomedogenicity in skin and personal-care products. Therefore, reactions that convert only 50% of the available hydroxyl groups of the lesquerella oil to cinnamoyl-esters are preferred.     

Effect of the doses and nature of vegetable oil on carbon black/rubber interactions: Studies on castor oil and other vegetable oils

The effects of additives in various vegetable oils on the physical, mechanical, and adhesion properties of carbon black/rubber compounds were studied. Various doses of castor oil and some other oils such as paraffin oil, vegetable oil 1, and cashew nut shell liquid (CNSL) at a fixed dose (1 phr) were used. With an increase in the castor oil content, the modulus, tear strength, and tensile strength increased, whereas the hardness and adhesive strength exhibited little variation up to 1 phr. Beyond 1 phr castor oil, the modulus, tear strength, and hardness decreased, whereas the adhesive and tensile strengths increased up to 2.5–3 phr and then decreased. Therefore, castor oil seemed to behave as a coupling agent up to 1 phr and as a coupling agent and a plasticizer in the range of 1–3 phr; beyond that, the main role of castor oil was plasticization. When various oils at a fixed dose (1 phr) were compared, it was found that the vegetable oils exhibited enhanced properties in comparison with those of paraffin oil. In addition, both of the unsaturated oils (castor oil and vegetable oil 1) enhanced physical and mechanical properties in comparison with saturated paraffin oil. CNSL exhibited the best adhesion properties against mild steel and galvanized iron substrates. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1574–1578, 2003     

Viscosity and rheological behavior of castor–canola mixture

In this work, the effects of shear rate on viscosity of selected pure food grade oils (castor and canola) are investigated. The rheological behavior of castor–canola oil mixture is also studied through modeling the experimental data. The effect of shear rate on the variation of viscosity was clearly observed. Interpretations of the results from rheological models indicate that these food grade oils belong to pseudo‐plastic category. The results also show that among the six used mixing rules, Grunberg–Nissan model seems very well fitted to the experimental data.     

Evaluation of Castor Oil Samples for Potential Toxin Contamination

Castor oil and its derivatives are widely used as a chemical feedstock for production of lubricants and greases, engineering plastics, plasticizers and surfactants. It also has wide application in consumer goods such as lipstick, deodorants and medicinal uses. Due to concerns about the possible presence of the ricin toxin in the oil, we have tested a collection of castor oils processed using different approaches, including cold‐pressed, US Pharmaceutical (USP) grade, and neutralized oils. Water soluble proteins were extracted from oil samples into phosphate‐buffered saline containing 0.05 % bovine serum albumin (PBSB) and analyzed for potential ricin contamination by ELISA. Our results indicate that only the cold‐pressed castor oil contained measurable levels of the toxin, estimated to be 35 ± 13 μg/l. A normal oral dose of castor oil for laxative use is 14 ml, so even cold‐pressed castor oil would be well below the toxic level of 1–5 μg/kg body weight. However, the presence of the toxin indicates that other soluble proteins, including allergens, may be present in cold‐pressed castor oil.     

Evaluation of the turbidity and thin layer chromatographic tests for detection of castor oil

Detection procedures for castor oil in genuine and treated groundnut oils were screened and false turbidity was noticed when ammonium molybdate/sulfuric acid reagents were added to rancid groundnut oil. Successively bleached and neutralized rancid groundnut oil samples do not respond to the tests. Turbidity did not appear for groundnut oils containing 10 and 20% castor oil and even for pure castor oil sample. Thin layer chromatography (TLC) was found to be quite effective for most of the treated, adulterated, genuine, old and fresh oil and fat samples, but showed a streaking, when applied to rancid groundnut oil. However, streaking could be greatly reduced and TLC could be successfully performed with bleached and neutralized, rancid groundnut oil samples.     

A simple and rapid polarimetric method for quantitative determination of castor oil

A simple and rapid polarimetric method is developed for quantitation of adulteration of castor oil in edible oils such as cottonseed, coconut, mustard, olive, palm, peanut, rice bran, safflower, soybean, and sunflower. The method is based on the optical activity of ricinoleic acid (12-hydroxy octadecenoic acid), a major constituent of castor oil. There is a good correlation between optical rotation and castor oil content in admixtures above 5%. Highly colored and viscous oils interfere in the measurement of optical activity. The method is highly specific and cost-effective. No solvents and chemicals are required for the analysis because no sample processing is involved in the present method.     

Detection of Rancid Groundnut Oil and its Differentiation from Castor Oil

Physico-chemical study, over a set of oxidized, bleached, neutralized groundnut oil samples and admixed samples of groundnut and castor oils, have been carried out to determine any possible deviation in their quality parameters, caused due to these treatments. Detection of rancid groundnut oil and its differentiation from castor oil can be accomplished qualitatively by use of methanolic sulfuric acid decomposition and ferrous ions induced cleavage methods. Few chemical spray reagents have also been selected and applied for detection and differentiation purpose on thin layer chromatoplates. Among the reagents, ferrous thiocyanate, potassium iodide and starch, alkaline permanganate, combinations of hydroiodic, hydrochloric, acetic acids and starch and hydroiodic acid and starch, found working as brown, blue, and yellow coloured sports could be seen for rancid groundnut oil on thin layer chromatoplates. Fresh groundnut and castor oils were silent in all the estimations, suggesting a clear distinction between castor oil and rancid groundnut oil.     

Composition of castor oil by optical activity

Summary The optical activity of castor oil and its derivatives has been studied. Pure methyl ricinoleate and methyl acetyl ricinoleate were prepared. The mixed methyl esters and acetylated methyl esters of castor oil were also prepared. By the determination of specific rotation of the pure and technical esters, the percentage of ricinoleate fraction can be deduced. This was calculated to be 93% and 90%, respectively. The esters of castor oil were calculated to contain 91.6% ricinoleate from the chemical hydroxyl value. This was about the average of the two values obtained optically and is believed close to the actual value. A number of castor oils were analyzed by both optical and chemical methods and found to be of nearly constant ricinoleic content. Dehydrated castor oil was found to have a comparative high specific rotation. This was believed due to its estolide content formed during dehydration.