Olive Oil Fatty Acids Research Articles

Thermosyntropha lipolytica gen. nov., sp. nov., a lipolytic, anaerobic, alkalitolerant, thermophilic bacterium utilizing short- and long-chain fatty acids in syntrophic coculture with a methanogenic archaeum.

Three strains of an anaerobic thermophilic organoheterotrophic lipolytic alkalitolerant bacterium, Thermosyntropha lipolytica gen. nov., sp. nov. (type strain JW/VS-265T; DSM 11003), were isolated from alkaline hot springs of Lake Bogoria (Kenya). The cells were nonmotile, non-spore forming, straight or slightly curved rods. At 60 degrees C the pH range for growth determined at 25 degrees C [pH25 degrees C] was 7.15 to 9.5, with an optimum between 8.1 and 8.9 (pH60 degrees C of 7.6 and 8.1). At a pH25 degrees C of 8.5 the temperature range for growth was from 52 to 70 degrees C, with an optimum between 60 and 66 degrees C. The shortest doubling time was around 1 h. In pure culture the bacterium grew in a mineral base medium supplemented with yeast extract, tryptone, Casamino Acids, betaine, and crotonate as carbon sources, producing acetate as a major product and constitutively a lipase. During growth in the presence of olive oil, free long-chain fatty acids were accumulated in the medium but the pure culture could not utilize olive oil, triacylglycerols, short- and long-chain fatty acids, and glycerol for growth. In syntrophic coculture (Methanobacterium strain JW/VS-M29) the lipolytic bacteria grew on triacylglycerols and linear saturated and unsaturated fatty acids with 4 to 18 carbon atoms, but glycerol was not utilized. Fatty acids with even numbers of carbon atoms were degraded to acetate and methane, while from odd-numbered fatty acids 1 mol of propionate per mol of fatty acid was additionally formed. 16S rDNA sequence analysis identified Syntrophospora and Syntrophomonas spp. as closest phylogenetic neighbors.

Gas Chromatographic Differentiation of Virgin, Refined, and Solvent-Extracted Olive Oils

Abstract An analytical method based on gas chromatography using a capillary column was used to determine fatty acids in olive oils. The method was applied to 50 samples of virgin olive oil, 50 of refined olive oil, and 30 of solvent-extracted olive oil. Results were compared, with special emphasis on peaks of minor fatty acids to distinguish virgin, refined, and solvent-extracted oils. Some peaks are probably due to trans Isomers of the fatty acids. Statistically significant differences were observed among the 3 types of olive oil.

An automated flow-reversal injection/liquid—liquid extraction approach to the direct determination of total free fatty acids in olive oils

A continuous liquid-liquid extraction system based on an automated, simplified single-channel flow-reversal injection mode involving no segmentation or separation unit is proposed for the direct determination of total free fatty acids (FFA) in olive oils. It relies on the reaction between the Cu 2+-pyridine complex and FFA, which takes place at the organic-aqueous interface, the Cu 2+-FFA complex (copper soap) thus formed being extracted into the organic phase during the flow-reversal process. Continuous monitoring of the organic phase at 716 nm by means of a photometer located in the middle of the injection loop provides a multi-peak absorbance-time profile representing multiple reversals in the dynamic extraction process. Total FFA can thus determined in contents from 0.01 to 1.5% (3.5 × 10 −4 − 5.3 × 10 −2, M) for oleic acid in toluene-diluted oil samples (corresponding to 0.06–9.0% of FFA for original samples) with relative standard deviations in the range 4.9–7.8% and a sampling frequency of 12 h −1. The results provided by the proposed method are in accordance with those obtained with a manual procedure and comparable to those afforded by a standard acid-base titration method after appropriate correction.

Effect of saline irrigation water on olive oil composition

AbstractVirgin olive oils were obtained in Egypt from fruits of olive trees irrigated with waters of different salinity concentration (control, 1800, 3600 and 6000 ppm) during the 1992 season. The effect of water salinity on olive oil fatty acid, fatty acid location in triacylglycerol moiety, triacylglycerol, sterol and tocopherol composition was determined. Oleic acid slightly increased and linoleic decreased in the total fatty acid composition, as well as on glycerol carbon‐2 and‐1(3), with increased water salinity. Trioleoyl, stearoyldioleoyl and palmitoyldioleoyl glycerols are slightly increased with increased water salinity. Total tocopherol was 87.7 mg/kg in the control and increased to 147.0 mg/kg for water with 1800 ppm salinity. At higher salinity concentration, total tocopherol decreased to 107.2 and to 89.1 mg/kg for water salinities of 3600 and 6000 ppm, respectively. The same trend was observed for α, β and γ‐tocopherols. Campesterol and β‐sitosterol were increased with water salinity of 1800 ppm and decreased when water salinity increased further. Stigmasterol increased at water salinity of 3600 ppm and decreased sharply when the salinity was increased to 6000 ppm. These olive oil composition studies showed that although water salinity may have some compositional effects, there was no major adverse effect on fatty acid, triacylglycerol, triacylglycerol fatty acid location, sterol and tocopherol composition for oil from olives of trees grown with water with a salt composition of up to 6000 ppm.

Rapid incorporation of fish or olive oil fatty acids into rat hepatic sinusoidal cell phospholipids after continuous enteral feeding during endotoxemia

Therapeutic modalities that downregulate macrophage and endothelial production of eicosanoid mediators by displacing membrane arachidonic acid (20:4 omega 6) may benefit patients at increased risk of septic complications. The objective of this study in rats was to assess the incorporation of fish or olive oil fatty acids into hepatic Kupffer and endothelial (K&E) cell phospholipids after 4 d of continuous enteral feeding during endotoxemia. Either endotoxin (ETX) (0.5-1 mg-1.day-1) or vehicle was infused intravenously during the last 72 h. Dietary fish and olive oil fatty acids were rapidly incorporated into both K&E and plasma phospholipids irrespective of ETX cotreatment. Rats infused with the fish oil-enriched diet had a significantly lower relative percent of both K&E linoleic acid (18:2 omega 6) and 20:4 omega 6, whereas rats infused with the olive oil-enriched diet only had a lower relative percent of 18:2 omega 6 compared with control rats receiving corn oil. Provision of specific dietary lipids by continuous enteral infusion may prove efficacious for the rapid modulation of hepatic sinusoidal cell membrane fatty acids under either normal or endotoxemic conditions.

Effect of scaling on class modeling with the simca method

The first step in multivariate analysis is almost always the scaling of the variables. The pattern recognition technique SIMCA provides the possibility of scaling the variables over all the objects of the training set (classical scaling), or only over the objects belonging to the same group (separate scaling). The former method of scaling is the more used. The effect of separate scaling on the classification of objects with SIMCA is investigated for a data set consisting of the percentage distribution of fatty acids in olive oils originating from two neighbouring regions in Italy. It is shown that separate scaling has a beneficial effect on the classification.

Lipase Induction in Mucor hiemalis

The influence on lipase induction in Mucor hiemalis of different types of triglycerides containing mainly oleic acid (olive oil), erucic acid (mustard oil), or saturated fatty acids of 8 to 16 carbons (coconut oil) was studied. The fungus was grown in shake flasks in a fermentation medium containing peptone, minerals, and glucose or one of the oils as the carbon source. Maximum lipase was produced when the initial pH of the fermentation medium was kept at 4.0. Addition of Ca to the medium did not increase lipase production. The optimum pH for activity of both the mycelial and extracellular lipases was found to be 7.0. The fungus produced a significant amount of lipase in the presence of glucose, but the lipase activity increased markedly when olive oil was added to the medium at the beginning of the fermentation. Addition of olive oil at a later stage did not induce as much enzyme. Studies with washed mycelia showed that a greater amount of lipase was released when olive oil was present than when glucose was present. Among the various types of triglycerides used as the carbon source, olive oil was found to be most effective in inducing the lipase. Olive oil and mustard oil fatty acids inhibited the lipase more than those of coconut oil. The lipase induced by a particular type of triglyceride did not seem to be specific for the same triglyceride, nor was it inhibited specifically by it. Irrespective of the triglyceride used in the fermentation medium, the lipase produced was most active against coconut oil triglyceride, and this specificity, as shown by lipase activities in an n-heptane system, was not found to be due to a better emulsification of this oil. The lipase of M. hiemalis can be considered to be both constitutive and inducible.

Desaturation and Saturation of Fatty Acids by Sheep Rumen Bacteria: Optimal Conditions and Cofactor Requirements

Optimal conditions for aerobic formation and anaerobic biohydrogenation of linoleic acid were determined in sheep rumen fluid with added olive oil fatty acids. Both activities were highest at 38C. Formation of linoleic acid exhibited maxima at pH 5.0 and 7.5, and hydrogenating activity was highest at pH 6.0.Washed rumen bacteria suspended in phosphate buffer showed a requirement for reduced pyridine nucleotides in the aerobic formation of linoleic acid. Cysteine, quinol, and sucrose enhanced anaerobic hydrogenation and induced saturation of linoleic acid even under aerobic conditions. Addition of l-14carbon labeled oleic and linoleic acid revealed a bidirectional flux of label between the monoene and diene fraction upon aerobic incubation.

EFFECTS OF SATURATED FAT IN RATS FED RAPESEED OIL

The effects of increasing the saturated fatty acids in a dietary vegetable oil composed mostly of unsaturated fatty acids were studied in rats. A mixture of palm oil and Swedish rapeseed oil fed for 4 weeks as 20% of a purified diet promoted weight gains which exceeded those obtained with Polish rapeseed oil of a similar content of erucic acid, and altered the proportion of saturated fatty acids in the tissues to reflect that of the diet. When methyl esters of saturated fatty acids were added to Swedish rapeseed oil, similar effects on weight gain were not observed, but methyl esters of fatty acids from corn oil and rapeseed oil were shown to be of less nutritional value than the original glycerides. From fatty acids of olive oil, glycerides containing 3% palmitic acid were prepared, and produced weight gains which did not differ significantly from those of rats fed Polish rapeseed oil with a similar content of palmitic acid and 20% erucic acid. The characteristic effects of rapeseed oil are, therefore, attributed to its low content of saturated fatty acids as well as its high content of erucic acid.

EFFECTS OF SATURATED FAT IN RATS FED RAPESEED OIL

The effects of increasing the saturated fatty acids in a dietary vegetable oil composed mostly of unsaturated fatty acids were studied in rats. A mixture of palm oil and Swedish rapeseed oil fed for 4 weeks as 20% of a purified diet promoted weight gains which exceeded those obtained with Polish rapeseed oil of a similar content of erucic acid, and altered the proportion of saturated fatty acids in the tissues to reflect that of the diet. When methyl esters of saturated fatty acids were added to Swedish rapeseed oil, similar effects on weight gain were not observed, but methyl esters of fatty acids from corn oil and rapeseed oil were shown to be of less nutritional value than the original glycerides. From fatty acids of olive oil, glycerides containing 3% palmitic acid were prepared, and produced weight gains which did not differ significantly from those of rats fed Polish rapeseed oil with a similar content of palmitic acid and 20% erucic acid. The characteristic effects of rapeseed oil are, therefore, attributed to its low content of saturated fatty acids as well as its high content of erucic acid.

Quantitative estimation of the fatty acids of olive oil.

BEFORE making a systematic study of the fatty acid composition of Spanish olive oils it was necessary to devise a procedure which combined precision and accuracy with speed. In this brief account we present a summary of the results obtained in our work, involving (1) spectrophotometry and (2) quantitative paper chromatography of the saturated acids.

A new oxidation method for the determination of saturated fatty acids

SummaryA method for the quantitative determination of the saturated acids in fats has been developed. This method is based upon the non‐disruptive oxidation of the unsaturated acids by performie acid, extraction of the oxidized mixture with petroleum ether and, finally, chromatographie purification of the saturated acids. The final residue contains a small quantity of non‐acid material, usually 0.1 to 0.7%, based on the total mixed fatty acids. The unsaturation of these saturated acids is equivalent to about 0.1%, as oleic acid, so that a total absolute correction of about 0.4% must be applied. The method is fairly simple and rapid, requiring about six hours for one determination and can be applied to a wide variety of fats.The method has been tested with known mixtures of pure saturated and unsaturated acids, with results varying up to 0.6% from the calculated values. Recovery of added saturated acids to olive oil fatty acids has also been satisfactory. Application of the method to the common fats shows good reproducibility, with results that compare favorably with the best accepted values. Fats containing distinctive acids, such as isooleic, eleaostearic, chaulmoogric, and rieinoleic acid, presented no analytical difficulties. However celery seed oil (petroselinic acid) contains interfering nonfatty material so that the final residue must be further purified. The method can also be used with fats containing lauric, capric, and small quantities of caprylic acids but is not satisfactory when appreciable quantities of water‐soluble saturated acids are present.

A study of the hexabromide number and hexabromide yield of pure linolenic acid with a suggested interpolation method for its estimation

Summary Varying amounts of a specimen of pure linolenic acid have been brominated and the hexabromide yields have been determined by an empirical procedure. The acid was brominated alone and in the presence of olive oil fatty acids. It is suggested that linolenic acid can be specifically and quantitatively determined in fatty acid mixtures by interpolation from a curve showing the linolenic acid‐hexabromide yield relationships over the range cited. The empirical nature of the hexabromide yield is confirmed.