Degree Of Fatty Acid Unsaturation Research Articles

Evaluation of Fatty Acid Profile of Wagyu Beef by ATR-FTIR Spectroscopy

Japanese black Wagyu beef has its characteristics of fatty well-marbled texture, flavor, and tenderness which are affected by fatty acid composition. The aim of this study was to develop an analytical method for evaluating the fatty acid profile of Wagyu beef by Fourier transform infrared (FTIR) spectroscopy. In the current study, attenuated total reflection–FTIR (ATR-FTIR) spectroscopy and gas chromatography (GC) were applied to the fat tissues, and the solvent-extracted fats which were sampled from subcutaneous, inter- and intramuscular fat tissues. Results of GC analysis showed that monounsaturated fatty acids (MUFA) content became larger in the order of intramuscular, intermuscular, and subcutaneous fats, and saturated fatty acids (SFA) became smaller in the same order. Subcutaneous fat could be discriminated from inter- and intramuscular fats on the basis of fatty acid composition by principal component analysis. The ATR-FTIR analysis revealed that the shift of the peak positions of alkene C–H stretching vibration at around 3,006 cm−1 occurred depending on the unsaturation degree of fatty acids in beef fat. Partial least squares (PLS) regression analysis with leave-one-out cross-validation was applied to the combined regions of 2,800–3,050 and 1,000–1,500 cm−1 for the fat tissues and the extracted fats. The correlation coefficients of the PLS validation models predicting the content of the MUFA and SFA for solvent-extracted fats were higher than those for fat tissues, and the coefficients (R 2) of determination more than 0.873 were obtained for solvent-extracted fats and 0.522 for fat tissues.

Carotenoid and fatty acid metabolism in light‐stressed Dunaliella salina

beta-Carotene is overproduced in the alga Dunaliella salina in response to high light intensities. We have studied the effects of a sudden light increase on carotenoid and fatty acid metabolism using a flat panel photobioreactor that was run in turbidostat mode to ensure a constant light regime throughout the experiments. Upon the shift to an increased light intensity, beta-carotene production commenced immediately. The first 4 h after induction were marked by constant intracellular levels of beta-carotene (2.2 g LCV(-1)), which resulted from identical increases in the production rates of cell volume and beta-carotene. Following this initial phase, beta-carotene productivity continued to increase while the cell volume productivity dropped. As a result, the intracellular beta-carotene concentration increased reaching a maximum of 17 g LCV(-1) after 2 days of light stress. Approximately 1 day before that, the maximum beta-carotene productivity of 30 pg cell(-1) day(-1) (equivalent to 37 mg LRV(-1) day(-1)) was obtained, which was about one order of magnitude larger than the average productivity reported for a commercial beta-carotene production facility, indicating a vast potential for improvement. Furthermore, by studying the light-induced changes in both beta-carotene and fatty acid metabolism, it appeared that carotenoid overproduction was associated with oil globule formation and a decrease in the degree of fatty acid unsaturation. Our results indicate that cellular beta-carotene accumulation in D. salina correlates with accumulation of specific fatty acid species (C16:0 and C18:1) rather than with total fatty acid content.

Forty Percent Methionine Restriction Decreases Mitochondrial Oxygen Radical Production and Leak at Complex I During Forward Electron Flow and Lowers Oxidative Damage to Proteins and Mitochondrial DNA in Rat Kidney and Brain Mitochondria

Eighty percent dietary methionine restriction (MetR) in rodents (without calorie restriction), like dietary restriction (DR), increases maximum longevity and strongly decreases mitochondrial reactive oxygen species (ROS) production and oxidative stress. Eighty percent MetR also lowers the degree of membrane fatty acid unsaturation in rat liver. Mitochondrial ROS generation and the degree of fatty acid unsaturation are the only two known factors linking oxidative stress with longevity in vertebrates. However, it is unknown whether 40% MetR, the relevant methionine restriction degree to clarify the mechanisms of action of standard (40%) DR can reproduce these effects in mitochondria from vital tissues of strong relevance for aging. Here we study the effect of 40% MetR on ROS production and oxidative stress in rat brain and kidney mitochondria. Male Wistar rats were fed during 7 weeks semipurified diets differing only in their methionine content: control or 40% MetR diets. It was found that 40% MetR decreases mitochondrial ROS production and percent free radical leak (by 62-71%) at complex I during forward (but not during reverse) electron flow in both brain and kidney mitochondria, increases the oxidative phosphorylation capacity of brain mitochondria, lowers oxidative damage to kidney mitochondrial DNA, and decreases specific markers of mitochondrial protein oxidation, lipoxidation, and glycoxidation in both tissues. Forty percent MetR also decreased the amount of respiratory complexes I, III, and IV and apoptosis-inducing factor (AIF) in brain mitochondria and complex IV in kidney mitochondria, without changing the degree of mitochondrial membrane fatty acid unsaturation. Forty percent MetR, differing from 80% MetR, did not inhibit the increase in rat body weight. These changes are very similar to the ones previously found during dietary and protein restriction in rats. We conclude that methionine is the only dietary factor responsible for the decrease in mitochondrial ROS production and oxidative stress, and likely for part of the longevity extension effect, occurring in DR.

Oxidizability of unsaturated fatty acids and of a non-phenolic lignin structure in the manganese peroxidase-dependent lipid peroxidation system

Unsaturated fatty acids have been proposed to mediate the oxidation of recalcitrant, non-phenolic lignin structures by fungal manganese peroxidases (MnP), but their precise role remains unknown. We investigated the oxidizability of three fatty acids with varying degrees of polyunsaturation (linoleic, linolenic, and arachidonic acids) by measuring conjugated dienes formation when lipid peroxidation was initiated either by MnP in the presence of Mn(II) or by chelated Mn(III). An inverse relationship between the degree of fatty acid unsaturation and the rate of peroxidation was found in both cases, but we also noted some differences between the two types of reaction. With MnP/Mn(II), the reaction developed slowly and resulted in sustained lipid peroxidation as determined by the formation of late-stage fatty acid degradation products. By contrast, the reaction with chelated Mn(III) was very rapid and did not result in the formation of these late-stage products, which suggests that this system failed to propagate the sustained radical chain reaction that is characteristic of complete lipid peroxidation. All three polyunsaturated fatty acids supported the co-oxidation of a non-phenolic lignin model compound by MnP, again showing an inverse relationship between the degree of unsaturation and reactivity, but chelated Mn(III) by itself supported only very low levels of fatty acid-mediated lignin model oxidation. These parallels in fatty acid reactivity are consistent with a reaction scheme in which Mn(III) acts as the proximal oxidant that initiates lipid peroxidation by MnP, thus generating fatty acid-derived radicals which in turn oxidize lignin structures. However, the results also suggest that the initial peroxyl radicals formed may not be the ligninolytic oxidants in this system. Instead, other radical oxidants produced during late-stage reactions of lipid peroxidation may be required.

Studying different dimensions of amylose–long chain fatty acid complexes: Molecular, nano and micro level characteristics

Recently amylose inclusion complexes, or V-amylose, have drawn much attention as a possible vehicle for the nanoencapsulation of unsaturated fatty acids. This study aimed to study three different structural strata of V-amylose, the molecular attributes using XRD, DSC and 13C CP/MAS NMR and the nanostructures using SAXS. Using these methods it was noted that decreased degree of fatty acid unsaturation induces the formation of more organized and well defined structures. Specifically, calculations based on SAXS data show that regardless of the crystallization temperature saturated SA yields the highest values for parameters like average crystalline lamellar thickness ( φ = 0.26) and characteristic particle dimension ( R g = 9.6). SEM shows this trend extends even into the microscopic level. Overall, this study shows that in the case of long chain fatty acids, increased fatty acid unsaturation impairs the structure of amylose inclusion complexes.

Citations

Citations

Alterações dos óleos de palma e de soja em fritura descontínua de batatas

Óleos de palma e de soja foram utilizados em experimentos de fritura de batatas em fritadeiras elétricas domésticas de 1 L com relação inicial, superfície sobre volume, de 0,3 cm-1. Em cinco dias consecutivos cada óleo foi submetido por um período de 5 horas por dia à temperatura de (183,1 ± 1,7) °C. Após 25 horas, a perda de ácidos graxos foi de 15,0 e 62,2% (m/m), respectivamente, para os ácidos oléico e linoléico, no óleo de palma; e de 6,5; 24,9 e 39,7% (m/m), respectivamente, para os ácidos oléico, linoléico e linolênico, no óleo de soja. Os teores inicial e final de polímeros foram de 0,4 e 23,7% (m/m) no óleo de palma, e de 0,5 e 30,7% (m/m) no óleo de soja. A relação entre a perda dos ácidos graxos e a formação de polímeros mostrou uma correlação forte com coeficientes de correlação de 0,9951 e 0,9740 para os óleos de palma e de soja, respectivamente. Concluiu-se que maiores graus de alteração ocorreram em ácidos graxos mais insaturados; e que a alteração pode ser eficazmente verificada através da determinação quantitativa de polímeros.

Importance of lipidic acyl chains in the process of biochemical thermal adaptation of Cunninghamella japonica mucoraceous fungus

The temperature of C. japonica cultivation influences the lipid content and composition of acyl chains, especially the content of such polyunsaturated acids as linoleic and linolenic. Thermal adaptation is accompanied by the modulation of fatty acid isomeric composition and acyl chain length and, at low temperatures, promotes the appearance of fatty acids uncommon to the fungus, in particular, arachidonic acid. The changes occur on a background of significant alterations in the fungus metabolism (in glucose uptake, ATP content, economic coefficient value, etc.). In experiments on the inhibition of translation with cycloheximide, abrupt temperature change (supraoptimal to cold) did not lead to desaturase de novo synthesis, but rather stimulated the activity of the named enzymes, except for palmitoleoyl-CoA desaturase. In the process of temperature adaptation, polar lipid microviscosity modulating compounds influenced fatty acid acyl chain composition. Microviscosity differences between polar and neutral lipids and correlation to the degree of fatty acid unsaturation during temperature fluctuation were established.

SALT‐INDUCED ALTERATIONS IN LIPID COMPOSITION OF DIATOM NITZSCHIA LAEVIS (BACILLARIOPHYCEAE) UNDER HETEROTROPHIC CULTURE CONDITION1

The diatom Nitzschia laevis Hust. is a potential producer of eicosapentaenoic acid (EPA). To elucidate its cellular response to salt stress, the effects of salinity on EPA production, lipid composition, and fatty acid distribution in the lipid pool were investigated. The highest contents of total fatty acids, EPA, and polar lipids were all obtained at NaCl of 20 g · L(-1) , under which 71.3% of total EPA existed in polar lipid fractions. In N.laevis, high salt concentration might induce the decrease in neutral lipids (NLs), whereas the production of polar lipids, including phospholipids (PLs) and glycolipids (GLs), was enhanced. The degree of fatty acid unsaturation of both neutral and polar lipid fractions increased sharply when NaCl concentration increased from 10 to 20 g · L(-1) but decreased at NaCl concentration of 30 g · L(-1) . The amount of total free sterols was increased with the increase in salt concentration. All these changes in lipid and fatty acids suggested a decrease in membrane permeability and fluidity under high salt concentration, which could help the alga acclimate to the salinity stress.

Unsaturated Fatty Acids in Alkane Solution: Adsorption to Steel Surfaces

Fatty acids and blends of fatty acids are used as friction modifiers and anti-wear additives in diesel fuels. A large part of some fatty acid blends are unsaturated fatty acids. Even though fatty acids have been thoroughly investigated, the adsorption and tribological behaviour of unsaturated fatty acids are no fully understood. The aim of this thesis was to investigate the influence of fatty acid unsaturation on the adsorption from alkane solution and the tribological properties, such as friction and wear scar characterization, of such systems. To increase the fundamental understanding of the influence of the degree of fatty acid unsaturation the three fatty acids, oleic, linoleic and linolenic acid, have been studied. In boundary lubrication the amount of material and how well the material is bound to the surface can affect the friction and wear of the system. Thus, as a first step the adsorption of fatty acids onto steel surfaces was investigated with the quartz crystal microbalance (QCM). This technique is straight forward to used and is ideal for these samples that are difficult to investigate with optical techniques due to small differences in refractive index between the alkane solvent and fatty acid. To determine the chemical binding to steel surfaces static secondary ion mass spectroscopy (SIMS) has been used. Next, the influence of fatty acid unsaturation on the friction and wear was determined. Two different studies were made, one on a molecular level with the tribological surfaces forces apparatus (T-SFA) and the other one with a technique used for determining friction and wear of diesel fuel additives. The T-SFA technique provides data from which the packing of the fatty acids at mica surfaces can be estimated as well as how the friction is altered due to the packing. For determining the friction and wear of steel surfaces the high frequency reciprocating rig (HFRR) and pin on disc apparatus (POD) were used. The HFRR is a standardized technique, where, if the settings specified in the ISO12156 protocol are used, a diesel fuel additive must provide an average wear scar radius less than 0.230 mm to pass. The wear scars received from the two techniques were further analysed with Raman spectroscopy and also a visual rating of the wear scars was performed. As the project progressed, there was an increasing interest in the influence of water on the adsorption and lubricating properties of the fatty acids. Moisture uptake of the fatty acids was therefore determined gravimetrically as well as with nuclear magnetic resonance spectroscopy (NMR). The adsorption of the moist fatty acids onto steel surfaces was then investigated with QCM and static SIMS, while HFRR and POD were used for investigate the friction and wear.

The effect of glycerol as a sole and secondary substrate on the growth and fatty acid composition of Rhodotorula glutinis

Rhodotorula glutinis is a yeast that produces copious quantities of lipids in the form of triacylglycerols (TAG) and can be used to make biodiesel via a transesterification process. The ester bonds in the TAG are broken leaving behind two products: fatty acid methyl esters and glycerol that could provide an inexpensive carbon source to grow oleaginous yeast R. glutinis. Described here are the effects of different growth substrates on TAG accumulation and fatty acids produced by R. glutinis. Yeast cultured 24 h on medium containing dextrose, xylose, glycerol, dextrose and xylose, xylose and glycerol, or dextrose and glycerol accumulated 16, 12, 25, 10, 21, and 34% TAG on a dry weight basis, respectively. Lipids were extracted from R. glutinis culture and transesterified to form fatty acid methyl esters. The results show a difference in the degree of saturation for the carbon sources tested. Cells cultivated on glycerol alone had the highest degree of unsaturated fatty acids at 53% while xylose had the lowest at 25%. R. glutinis can be cultivated on all sugars tested as single carbon substrates or in mixtures. Glycerol may be used as secondary or primary carbon substrate.

Effect of Every Other Day Feeding on Mitochondrial Free Radical Production and Oxidative Stress in Mouse Liver

It is known that dietary restriction (DR) increases maximum longevity in rodents, but the mechanisms involved remain unknown. Among the possible mechanisms, several lines of evidence support the idea that decreases in mitochondrial oxidative stress and in insulin signaling are involved but it is not known if they are interconnected. It has been reported that when C57BL/6 mice are maintained on an every other day (EOD) feeding their overall food intake is only slightly decreased and plasma insulin-like growth factor (IGF)-1 is even somewhat increased. In spite of this, their maximum longevity is increased, analogously to what occurs in classic DR. Thus, this model dissociates the increase in longevity from the decrease in IGF-1 observed in classic DR. Based on these facts, we have studied the effect of EOD DR on the rate of mitochondrial reactive oxygen species (ROS) production, oxygen consumption, and the percent free radical leak (FRL) of well-coupled liver mitochondria, the marker of mtDNA oxidative damage 8-oxo-7,8-dihydro-2'deoxyguanosine (8-oxodG), the content of complexes I to IV of the respiratory chain, the apoptosis inducing factor (AIF), PGC1-alpha, UCP2, five different markers of oxidative damage to proteins and the full fatty acid composition on C57BL/6 mice liver. It was found that EOD DR decreased ROS production in complex I but not in complex III without changes in oxygen consumption. As a result, FRL was decreased in complex I. Oxidative damage to mtDNA (8-oxodG) and protein oxidation, glycoxidation and lipoxidation were also lower in the EOD restricted group in comparison with the control one while the degree of fatty acid unsaturation was held constant. The EOD group also showed decreases in AIF, PGC1-alpha, and UCP2. These results support the possibility that EOD DR increases maximum life span at least in part through decreases in mitochondrial oxidative stress which are independent from insulin/IGF-1-like signaling.

Role of lipoperoxidation and sulfhydryl oxidation on sensitization of mitochondrial complex III to oxidative damage by Fe2+

Mitochondrial fatty acids (FA) are key oxidative stress (OE) targets. FA peroxidation propensity augments as its unsaturation degree (UD) increase. Thus, augment on UD of FA from mitochondrial membranes may exacerbate mitochondrial damage during OE. This aspect has physiological importance because increasing fashion in population to ingest polyunsaturated FA. To investigate the influence of UD over the damage to electron transport chain (ETC) by OE, as well localization and chemical nature of damage, we used S. cerevisiae mitochondria as model because its membrane FA content can be manipulated. In mitochondria with monounsaturated FA, lipoperoxidation levels were unaffected by 50 μM Fe2+, while only complex III activity was inhibited by 50%. Damage on complex III was attributed mainly to OH• attack because mannitol partially protected against activity impairment. In contrast, in mitochondria with linolenic acid (C18:3, 80% of total FA), Fe2+ increased ten‐fold lipoperoxidation levels and fully inhibits complex III, which was prevented in 75% and 23% by the anti‐lipoperoxidative agent BHT and β‐mercaptoethanol, respectively, indicating a dual damage on –SH groups and lipids. These results show that lipoperoxidation sensitize ETC towards oxidative damage, being complex III the most labile enzyme affected by –SH and lipid oxidation. Supported by Fondos Mixtos CONACYT‐ Gob. Edo. de Michoacán (64277, 64308), COECYT and CIC‐UMSNH (2.16) grants.

The effect of cadmium on lipid and fatty acid biosynthesis in tomato leaves

AbstractThis research aims to examine the effect of cadmium uptake on lipid composition and fatty acid biosynthesis, in young leaves of tomato treated seedlings (Lycopersicon esculentum cv. Ibiza F1). Results in membrane lipids investigations revealed that high cadmium concentrations affect the main lipid classes, leading to strong changes in their composition and fatty acid content. Thus, the exposure of tomato plants to cadmium caused a concentration-related decrease in the unsaturated fatty acid content, resulting in a lower degree of fatty acid unsaturation. The level of lipid peroxides was significantly enhanced at high Cd concentrations. Studies of the lipid metabolism using radioactive labelling with [1-14C]acetate as a major precursor of lipid biosynthesis, showed that levels of radioactivity incorporation in total lipids as well as in all lipid classes were lowered by Cd doses. In total lipid fatty acids, [1-14C]acetate incorporation was reduced in tri-unsaturated fatty acids (C16:3 and C18:3); While it was enhanced in the palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0) and linoleic (C18:2) acids. [1-14C]acetate incorporation into C16:3 and C18:3 of galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] and some phospholipids [phosphatidylcholine (PC) and phosphatidylglycerol (PG)] was inhibited by Cd stress. Our results showed that in tomato plants, cadmium stress provoked an inhibition of polar lipid biosynthesis and reduced fatty acid desaturation process.

Chemical composition and oxidative stability of flax, safflower and poppy seed and seed oils

Three seeds of Turkish origin, flax, poppy and safflower were analyzed for their proximate, fatty acids, tocols (tocopherols and tocotrienols) and total phenolic composition, and oxidative stability of their oil. The major fatty acid in the flax oil was α-linolenic acid, comprising 58.3% of total fatty acids, whereas poppy and safflower oils were rich in linoleic acid at 74.5% and 70.5% level, respectively. The amount of total tocols was 14.6 mg/100 g flax, 11.0 mg/100 g poppy and 12.1 mg/100 g safflower seed. Flax and poppy oil were rich in γ-tocopherol as 79.4 mg/100 g oil and 30.9 mg/100 g oil, respectively, while α-tocopherol (44.1 g/100 g oil) was dominant in safflower oil. Only α- and γ-tocotrienol were found in the oils. Oxidative stability of oils was measured at 110 °C at the rate of 20 L/h air flow rate, and poppy oil (5.56 h) was most stabile oil followed by safflower oil (2.87 h) and flax oil (1.57). There were no correlation between oxidative stability and unsaturation degree of fatty acids and tocol levels of the oils. All of the seeds investigated provide a healthy oil profile and may have potential as a source of specialty oils on a commercial scale.

Effects of acclimation temperature on thermal tolerance and membrane phospholipid composition in the fruit fly Drosophila melanogaster

Adaptative responses of ectothermic organisms to thermal variation typically involve the reorganization of membrane glycerophospholipids (GPLs) to maintain membrane function. We investigated how acclimation at 15, 20 and 25 °C during preimaginal development influences the thermal tolerance and the composition of membrane GPLs in adult Drosophila melanogaster. Long-term cold survival was significantly improved by low acclimation temperature. After 60 h at 0 °C, more than 80% of the 15 °C-acclimated flies survived while none of the 25 °C-acclimated flies survived. Cold shock tolerance (1 h at subzero temperatures) was also slightly better in the cold acclimated flies. LT50 shifted down by ca 1.5 °C in 15 °C-acclimated flies in comparison to those acclimated at 25 °C. In contrast, heat tolerance was not influenced by acclimation temperature. Low temperature acclimation was associated with the increase in proportion of ethanolamine (from 52.7% to 58.5% in 25 °C-acclimated versus 15 °C-acclimated flies, respectively) at the expense of choline in GPLs. Relatively small, but statistically significant changes in lipid molecular composition were observed with decreasing acclimation temperature. In particular, the proportions of glycerophosphoethanolamines with linoleic acid (18:2) at the sn-2 position increased. No overall change in the degree of fatty acid unsaturation was observed. Thus, cold tolerance but not heat tolerance was influenced by preimaginal acclimation temperature and correlated with the changes in GPL composition in membranes of adult D. melanogaster.

Variation of lipid class composition in Nitzschia laevis as a response to growth temperature change

The lipid composition and the distribution of fatty acids in the lipid pool were determined in eicosapentaenoic acid (EPA)-producing microalga (Nitzschia laevis) grown under different temperatures. Both the relative amounts of lipid classes and the degree of fatty acid unsaturation in various lipid species were not greatly changed under tested growth conditions. Higher temperature up to 23°C benefited the growth of N. laevis but only had a slight influence on EPA and lipid contents. Further increasing the culture temperature caused a serious inhibition of both the cell growth and fatty acid biosynthesis. Under all temperatures tested, triacylglycerol (TAG) was the predominant lipid constituent (64.5–69.1% of total lipid) and was highly saturated. Lower temperature favored the formation of polar lipids. The highest content of phosphatidylcholine (PC), the major phospholipids component, was reached at 15°C (10.9% of total lipid). In sharp contrast to TAG, PC was highly unsaturated and contained a higher amount of EPA under lower temperature. The highest EPA content in polar lipid was achieved at 19°C. The results from this investigation suggested that the low temperature could improve the distribution of polyunsaturated fatty acids in phospholipids, though it could not significantly influence their amount, especially in PC.

Effects of Cholesterol on Dry Bilayers: Interactions between Phosphatidylcholine Unsaturation and Glycolipid or Free Sugar

Cholesterol and other sterols are important components of biological membranes and are known to strongly influence the physical characteristics of lipid bilayers. Although this has been studied extensively in fully hydrated membranes, little is known about the effects of cholesterol on the stability of membranes in the dry state. Here, we present a Fourier transform infrared spectroscopy study on the effects of cholesterol on the phase behavior of dry liposomes composed of phosphatidylcholines with different degrees of fatty acid unsaturation or of mixtures of phosphatidylcholine with a plant galactolipid. In addition, we have analyzed the H-bonding of cholesterol, galactose, and a combination of the two additives to the P=O and C=O groups in dry phosphatidylcholine bilayers. The data indicate a complex balance of interactions between the different components in the dry state and a strong influence of fatty acid unsaturation on the interactions of the diacyl lipids with both cholesterol and galactose.

Seasonal Changes of Fatty Acid Compositions in Overwintering Larvae of Rice Stem Borer, Chilo suppressalis (Lepidoptera: Pyralidae)

Cold acclimation and overwintering state can affect fatty acid compositions of insects. To determine compositional change of fatty acids during nondiapause and diapause stages, an experiment was conducted to investigate fatty acid constituents from whole body of C. suppressalis larvae. Five most abundant fatty acids were found to be palmitoleic (35–58%), palmitic (18–44%), oleic (14–23%), stearic (0.5–2.5%) and linoleic acid (0.4–2%). However, linolenic, erucic, lauric and myristic acid were found at lower level. Saturated fatty acids significantly decreased and conversely unsaturated fatty acids increased from August (pre-diapause) to October (initiation of diapause). The increase in seasonal cold hardiness during cold acclimation, exposed at −15°C for 24 h, was related to degree of fatty acid unsaturation. The elevation of palmitoleic acid content at low temperature resulted in an increase in the overall degree of unsaturation in the whole body. These results indicated the importance of unsaturated fatty acids composition to prepare larvae entering diapause phase.

Role of Olive Oil and Monounsaturated Fatty Acids in Mitochondrial Oxidative Stress and Aging

The free radical theory of aging argues that free radicals produced by the mitochondria are responsible for the damage that affects all biological tissues and leads to the aging phenotype. High olive oil intake is related to lower mitochondrial oxidative stress, including that which happens during aging. The degree of fatty acid unsaturation of mammalian tissues is also negatively correlated with greater longevity, and olive oil leads to less polyunsaturated biological membranes. Finally, monounsaturated fatty acids (such as those of olive oil) have been associated with greater longevity and a high degree of protection against age-related cognitive decline in humans.