Proportions Of Individual Fatty Acids Research Articles

Circulating Fatty Acids Associate with Metabolic Changes in Adolescents Living with Obesity.

Fatty acids play a crucial role in obesity development and in the comorbidities of obesity in both adults and children. This study aimed to assess the impact of circulating fatty acids on biomarkers of metabolic health of adolescents living with obesity. Parameters such as blood lipids, redox status, and leukocyte telomere length (rLTL) were measured alongside the proportions of individual fatty acids. The Mann-Whitney U test revealed that individuals with obesity exhibited an unfavorable lipid and redox status compared to the control normal weight group. The group with obesity also had lower plasma n-3 polyunsaturated fatty acids (PUFAs) and a higher ratio of n-6 to n-3 PUFAs than the control group. They also had a shorter rLTL, indicating accelerated biological aging. There was an inverse association of rLTL and plasma n-6-to-n-3 PUFA ratio. Future studies should explore the impact of recommended nutrition plans and increased physical activity on these parameters to determine if these interventions can enhance the health and well-being of adolescents with obesity, knowing that early obesity can track into adulthood.

Matcha Green Tea: Chemical Composition, Phenolic Acids, Caffeine and Fatty Acid Profile.

Matcha-Japanese powdered tea-is a variety of green tea (Camellia sinensis L.), one of the most popular beverages in the world. Due to the unique way it is grown, it contains high concentrations of health-promoting phytochemicals. The aim of this study was to determine the basic nutritional and phenolic composition of dry matcha green tea powder. The fibre content was determined according to the enzymatic-gravimetric method. Crude protein was measured by the Kjeldahl method. The total fat content was measured by the Soxhlet method, and the fatty acid profile was defined by the GC method. The determination of the phenolic acid and caffeine content was performed using high-performance liquid chromatography. The total fibre content of matcha was 56.1 g/100 g, with 52.8 g/100 g (94.1% of total fibre) of insoluble dietary fibre and 3.3 g/100 g of soluble fibre (5.9% of total fibre). The total protein content was 17.3 g/100 g. The total fat content in dry matcha was 7.285 g/100 g, comprising varying proportions of individual fatty acids, the highest ones being those of linoleic acid and α-linolenic acid. The caffeine content of matcha tea was 2213.492 µg/g. With regard to phenolic acids, the highest content was estimated for gallic acid (252.3755 µg/g). Matcha showed a particularly high content of total dietary fibre, with a predominance of the insoluble fraction. Matcha was found to be a valuable source of plant protein and unsaturated fatty acids, mostly of the omega-3 fatty acid family.

Improved tenderness of beef from bulls supplemented with active dry yeast is related to matrix metalloproteinases and reduced oxidative stress

Supplementing diets with active dry yeast (ADY, Saccharomyces cerevisiae) improves the carcass quality grade of beef cattle and the tenderness of beef. The relevant mechanisms have not been fully elucidated, but may be related to the effect of ADY on oxidative stress and the activity of matrix metalloproteinases (MMPs). To provide further insight into these mechanisms, this study evaluated the influence of ADY supplementation on growth performance, carcass traits, meat quality, concentrations of MMPs in serum (MMP-2, MMP-9 and MMP-13), oxidative stress indices and antioxidant capacity indices in beef cattle. Forty-six crossbred Simmental × Yanbian bulls (∼18 months of age, BW 436 ± 35 kg) participated in a 145-day finishing trial. ADY supplementation significantly improved marbling deposition, intramuscular fat content, and beef tenderness (P < 0.05); altered individual fatty acid proportions in the beef and increased saturated fatty acids while decreasing polyunsaturated fatty acids (P < 0.05); significantly decreased the abundance of reactive oxygen species in serum and meat; significantly increased the level of superoxide dismutase in meat (P < 0.05); tended to increase the level of catalase (P = 0.075) in serum and glutathione reductase (P = 0.066) in meat; and increased the secretion of MMPs. The improvement of beef tenderness following ADY supplementation of finishing bulls is related to the effects of ADY on the secretion of MMPs and the lowering of oxidative stress.

Cold Exposure Affects Lipid Metabolism, Fatty Acids Composition and Transcription in Pig Skeletal Muscle.

Cold exposure promotes glucose oxidation and modulates the lipid metabolism in adipose tissue, but it is still not fully clear whether cold exposure could affect meat quality and fatty acid metabolism in skeletal muscle of pig in vivo. Here, we kept finishing pigs under cold or room temperature overnight and determined the effects of cold exposure on meat quality, fatty acids composition and transcriptional changes in skeletal muscle of pigs. We found that cold exposure significantly reduced the meat colour24 h and pH24 h, without affecting carcass characteristics and other meat quality traits. Considerable changes were found in the proportions of individual fatty acids and the total content of saturated fatty acid, polyunsaturated fatty acids, monounsaturated fatty acid and n3-fatty acids. RNA-seq results showed upregulated fatty acid biosynthesis genes and downregulated mitochondrial beta-oxidation genes. The lipid metabolism in cold-treated longissimus dorsi muscle might be regulated by functions of the lipoprotein particle, the extracellular matrix, and the PPAR signaling pathways. Our study revealed the potential of cold exposure to regulate the lipid metabolism and fatty acid composition in skeletal muscle of farmed animals.

Effect of Aging Time on Meat Quality of Longissimus Dorsi from Yunling Cattle: A New Hybrid Beef Cattle.

Simple SummaryBeef is in great demand in many countries. Consumers are more inclined to buy beef with good tenderness, color, flavor, and healthy fatty acid composition. Beef that has been aged is often more suitable for cooking and processing. A research gap exists regarding the analysis of meat quality during the aging process in Yunling cattle, a new hybrid beef cattle bred by Chinese researchers. This study measured a set of indicators of Yunling beef and other two breeds as controls (Simmental cattle, an excellent beef cattle breed used around the world, and Wenshan cattle, a local beef cattle breed in southern China), including the pH, water loss rate, cooking loss, Warner-Bratzler shear force, myofibrillar fragmentation index, inosine 5′-monophosphate, color, and fatty acid profiles. In addition, some growth performance and carcass characteristics were determined. The results showed that the pH, water holding capacity, growth performance, and carcass traits of Yunling and Simmental cattle were basically the same and better, respectively, than those of Wenshan cattle. Aging time had no effect on beef fatty acid composition, with Yunling beef showing a healthier fatty acid profile versus the other two breeds. With increased aging time, the tenderness and color of Yunling beef became more suitable for cooking and sensory characteristics. Therefore, this study suggests that Yunling beef should be used for cooking and processing after aging.The beef aging process is essential for compliance with certain major requisites, such as sensory characteristics for cooking and meat processing. Meat quality analysis of Yunling cattle, a new hybrid beef cattle bred by Chinese researchers, during the aging process, represents a major research gap. To explore Yunling beef initially, indicators associated with meat quality during the aging process of Yunling, Simmental, and Wenshan cattle were measured. In addition, some important economic traits were detected in the three breeds, including growth performance and carcass characteristics. The results showed that the growth performance, carcass traits, pH, and water holding capacity of Yunling and Simmental cattle were basically the same and better, respectively, than those of Wenshan cattle. The proportions of individual fatty acids in Yunling beef were healthier than in the other two breeds. Aging time did not affect the fatty acid profiles of the beef (p > 0.05). The contents of certain fatty acids in the three beef types displayed some differences in terms of days of aging (p < 0.05). The tenderness and meat color were better in the Yunling beef as the aging time increased, indicating that Yunling beef aged for 7 days was more suitable for cooking, exhibiting better sensory characteristics. Thus, a 7-day short-term aging process is very effective in improving the quality of Yunling beef. Our study attempted to fill a gap in the Yunling beef quality analysis during aging, providing further evidence for Yunling beef improvement.

Human milk fatty acid composition is associated with dietary, genetic, sociodemographic, and environmental factors in the CHILD Cohort Study

Fatty acids are a vital component of human milk. They influence infant neurodevelopment and immune function, and they provide ∼50% of milk's energy content. The objectives of this study were to characterize the composition of human milk fatty acids in a large Canadian birth cohort and identify factors influencing their variability. In a subset of the CHILD cohort (n=1094), we analyzed milk fatty acids at 3-4 mo postpartum using GLC. Individual and total SFAs, MUFAs, and n-3 and n-6 PUFAs were analyzed using SD scores and principal component analysis (PCA). Maternal diet, sociodemographic, health, and environmental factors were self-reported. Single-nucleotide polymorphisms were assessed in the fatty acid desaturase 1 (FADS1-rs174556) and 2 (FADS2-rs174575) genes. Fatty acid profiles were variable, with individual fatty acid proportions varying from 2- to >30-fold between women. Using PCA, we identified 4 milk fatty acid patterns: "MUFA and low SFA," "high n-6 PUFA," "high n-3 PUFA," and "high medium-chain fatty acids." In multivariable-adjusted analyses, fish oil supplementation and fatty cold water fish intake were positively associated with DHA and the "high n-3 PUFA" pattern. Mothers carrying the minor allele of FADS1-rs174556 had lower proportions of arachidonic acid (ARA; 20:4n-6). Independent of selected dietary variables and genetic variants, Asian ethnicity was associated with higher linoleic acid (18:2n-6) and total n-3 PUFAs. Ethnic differences in ARA were explained by FADS1 genotype. Maternal obesity was independently associated with higher total SFAs, the "high medium-chain fatty acid" pattern, and lower total MUFAs. Lactation stage, season, study site, and maternal education were also independently associated with some milk fatty acids. No associations were observed for maternal age, parity, delivery mode, or infant sex. This study provides unique insights about the "normal" variation in the composition of human milk fatty acids and the contributing dietary, genetic, sociodemographic, health, and environmental factors. Further research is required to assess implications for infant health.

Influence of different pig genotype on aroma, colour and fatty acid composition of smoked dry-cured ham

The aim of this study was to determine the influence of different genotypes of pigs ((Landrace x large Yorkshire) x Duroc (LYD) and Black Slavonian (BS) pig) on the colour, fat content and fatty acid composition of smoked dry-cured ham and identify volatile aroma-active compounds. The fat content was determined by applying the Smedes method and the composition of fatty acids by using the gas chromatography, while volatile aroma-active compounds were investigated by using the headspace-solid phase microextraction (HS-SPME) and the gas chromatography-mass spectrometry (GC-MS). Different genotypes of pigs did not show a statistically significant difference (p&amp;gt;0.05) in total fat content, but there was a difference in the proportion of individual fatty acids. We identified a total of 103 volatile compounds belonging to the following groups of chemical compounds: 19 aromatic hydrocarbons, 17 aliphatic hydrocarbons, 17 ketones, 15 phenols, 14 aldehydes, 11 alcohols, 5 acids, 2 terpenes and 1 sulphur compound. The most abundant chemical groups of compounds in samples of smoked dry-cured ham from LYD pigs were aldehydes, phenols and aromatic hydrocarbons, while the most abundant chemical groups of compounds in samples of smoked dry-cured ham of BS genotype were phenols, aldehydes and alcohols.

Fatty acid composition in maternal and foetal muscle tissues of beaver (Castor fiber)

The aim of the present work was to examine and compare the fatty acid composition of muscle tissues from eleven pregnant beaver (Castor fiber) females and their foetuses. The females were culled during warrantable early spring beaver hunting period (from the beginning of March until the middle of April). The fat content of the muscles of beaver female was 2.0 times higher (P < 0.001) than that of the muscles of their foetuses before birth. A total number of 33 and 34 fatty acids of various chain lengths and saturation levels, including 5 trans isomers, were identified, respectively, in the intramuscular fat (IMF) of muscle tissues from beaver females and their foetuses. Considerable differences in the proportions of individual fatty acids showed that foetuses during beaver gestation accumulate 1.4 times more total saturated (SFA) and 2.6 times more monounsaturated (MUFA) but 2.7 times less polyunsaturated (PUFA) fatty acids than pregnant females (P < 0.001). Although PUFA/SFA ratio in the tissues of foetuses was by 3.8 times lower (P < 0.001) than in the muscle tissue of females, the differences in n-6/n-3PUFA ratio were not significant (P = 0.133).

Influence of feeding supplements of almond hulls and ensiled citrus pulp on the milk production, milk composition, and methane emissions of dairy cows

Almond hulls and citrus pulp have been fed to dairy cows with variable responses for milk production, but no information exists on their effect on enteric methane emissions. This experiment examined the effects of dietary supplementation with either almond hulls or ensiled citrus pulp on the milk yield, milk composition, and enteric methane emissions of dairy cows. Thirty-two Holstein dairy cows in mid lactation were offered 1 of 3 diets over a 28-d experiment. Twelve cows received a control (CON) diet, 10 cows a diet containing almond hulls (ALH), and 10 cows a diet containing ensiled citrus pulp (CIT). All cows were offered 6.0 kg of dry matter (DM)/d of crushed corn, 2.0 kg of DM/d of cold-pressed canola, and 0.2 kg of DM/d of a mineral mix. In addition, cows fed the CON diet were offered 14.5 kg of DM/d of alfalfa cubes; cows fed the ALH diet were offered 10.5 kg of DM/d of alfalfa cubes and 4.0 kg of DM/d of almond hulls; and cows on the CIT diet were offered 11.5 kg of DM/d of alfalfa cubes and 3.0 kg of DM/d of ensiled citrus pulp. Milk yield was measured daily and milk composition was measured on 4 d of each week. Individual cow methane emissions were measured by a sulfur hexafluoride tracer technique on d 24 to 28 of the experiment. The mean milk yield of cows fed the CON diet (27.4 kg/d) was greater than the mean milk yield of cows fed the ALH diet (24.6 kg/cow per day), whereas the mean milk yield of cows fed the CIT diet (26.2 kg/cow per day) was not different from the mean milk yield from cows fed the other 2 diets. Dietary treatment did not influence the concentrations of milk fat, protein, and lactose or fat yields, but the mean protein yield from cows fed the CON diet (0.87 kg/d) was greater than that from cows fed the ALH diet (0.78 kg/d) but not different to those fed the CIT diet (0.85 kg/d). In general, we found no differences in the proportion of individual fatty acids in milk. The mean pH of ruminal fluid from cows offered the CON diet was not different to the pH in the ruminal fluids of cows offered the ALH or the CIT diets. The mean methane emissions (g/d) and yields (g/kg of DM intake) were not influenced by dietary treatment. These findings indicate that, although almond hulls and ensiled citrus pulp can be used as a low-cost feed supplement, almond hulls did negatively affect milk production and neither inhibited enteric methane emissions.

Proportion of oleic acid in olive oil as influenced by the dimensions of the daily temperature oscillation

Abstract Olive fruit dry weight, oil concentration and the proportions of individual fatty acids in the oil are influenced by environmental variables, such as ambient temperatures, between flowering and harvest. An increase in mean daily temperature above 25 °C has been shown to have a negative effect on fruit dry weight, and to produce a linear decrease both in fruit oil concentration and oleic acid proportion in the oil over the range of 16–32 °C. Under natural conditions or in experiments in which mean daily temperatures are manipulated following the natural daily oscillation in temperature, mean daily maximum and minimum temperatures covary with mean daily temperature. However, variations in temperature associated with altitude, location and climate change can affect maximum and minimum temperatures differently and modify thermal amplitude. The objectives of the present study were to assess associations between changes in: i) yield variables (fruit dry weight and oil concentration) and ii) the proportions of major fatty acids in the oil, with the different dimensions of the daily temperature oscillation (mean daily minimum and maximum temperatures, mean daily thermal amplitude) experienced by the fruit during its growth from the pit-hardening stage to maturity. Five branch-level temperature treatments were applied: a control (T0) that followed the daily dynamics of ambient temperature, two levels of daytime (8–20 h) heating that increased temperature 5 and 10 °C relative to T0 during the day, and two levels of nighttime (20–8 h) heating to 5 and 10 °C more than T0. Treatments were applied for 76 days during the oil accumulation phase using transparent chambers with individualized temperature control to enclose fruiting branches of cultivar Arauco trees. The treatments successfully broke the natural covariance between the different dimensions of daily temperature variation, and achieved a broad range in mean daily temperature (∼6 °C) which covered the natural range of this variable for the region. Fruit dry weight showed a tendency to decrease with increasing mean temperature, while the proportion of oil in the fruit exhibited a significant relationship (R2 = 0.70) with mean daily thermal amplitude, and weaker −but significant- ones with mean daily maximum and minimum temperatures. The proportion of the main fatty acid in the oil, oleic acid, showed significant negative associations with mean daily minimum temperature (R2 = 0.45) and with mean daily temperature (R2 = 0.32), and a significant curvilinear relationship with mean daily thermal amplitude, but was not significantly associated with mean maximum temperature. Mean daily thermal amplitude in our experiment was determined mainly by mean daily minimum temperatures, a feature also found in an analysis of meteorological data for five sites and five years in the olive producing areas of La Rioja province, Argentina. Our results highlight the need to broaden studies on the temperature responses of olive fruit size, oil content and oleic acid content of the oil to include the effects of minimum temperature and thermal amplitude.

Characterization of Mesocarp and Kernel Lipids from Elaeis guineensis Jacq., Elaeis oleifera [Kunth] Cortés, and Their Interspecific Hybrids.

Morphological traits, total lipid contents, and fatty acid profiles were assessed in fruits of several accessions of Elaeis oleifera [Kunth] Cortés, Elaeis guineensis Jacq., and their interspecific hybrids. The latter featured the highest mesocarp-to-fruit ratios (77.9-78.2%). The total lipid contents of both E.guineensis mesocarp and kernel were significantly higher than for E.oleifera accessions. Main fatty acids comprised C16:0, C18:1n9, and C18:2n6 in mesocarp and C12:0, C14:0, and C18:1n9 in kernels. E.oleifera samples were characterized by higher proportions of unsaturated long-chain fatty acids. Saturated medium-chain fatty acids supported the clustering of E.guineensis kernels in multivariate statistics. Hybrid mesocarp lipids had an intermediate fatty acid composition, whereas their kernel lipids resembled those of E.oleifera genotypes. Principal component analysis based on lipid contents and proportions of individual fatty acids permitted clear-cut distinction of E.oleifera, E.guineensis, and their hybrids.

Effect of temperature on growth and fatty acids profile of the biodiesel producing microalga Scenedesmus acutus

Description of the subject. The present study examined the effect of temperature (15, 20, 25, 30, 35 and 40 °C) on biomass, esterified fatty acids content and fatty acid productivity of Scenedesmus acutus. Objectives. This work aimed to study the effect of variation in temperature on lipid productivity and fatty acid profiles of S. acutus as a feedstock for biodiesel production. Method. The alga was grown under different temperatures and its biomass, as well as fatty acid content and composition, were determined. Results. The maximum growth rate of S. acutus was achieved at 30 °C , but there was no significant difference in biomass productivity at 25 and 30 °C (0.41 and 0.42 g·l-1·d-1), respectively. The highest fatty acid content (104.1 mg·g-1 CDW) was recorded at low temperature (15 °C) and decreased with increasing temperature. As a result of high biomass production, fatty acids productivity showed the highest values (41.27 and 42.10 mg·l-1·d-1) at 25 and 30 °C, respectively. The proportion of saturated and mono-unsaturated fatty acids increased from 13.72 to 23.79% and from 11.13 to 33.10% of total fatty acids when the incubation temperature was raised from 15 to 40 °C, respectively. The increase of temperature from 15 to 40 °C decreased the poly-unsaturated fatty acids from 75.15% to 43.10% of total fatty acids, respectively. Conclusions. The present study concluded that incubation temperature was a critical parameter for quantitative and qualitative fatty acid compositions of S. acutus. In addition, the type and proportion of individual fatty acids, which interfere with biodiesel quality, can be modified using different incubation temperatures in order to meet the biodiesel international standards.

Effects of dietary oil blend on fatty acid composition, oxidative stability and physicochemical properties of Longissimus thoracis et lumborum muscle in goats.

This study examined the effects of dietary blend of 80% canola oil and 20% palm oil (BCPO) on the physicochemical properties, antioxidant status, oxidative stability and fatty acid composition of Longissimus thoracis et lumborum (LTL) muscle from goats during chill storage. Over a 14-week feeding trial, 24 Boer bucks were randomly assigned to and supplemented with diets containing 0, 4 or 8% BCPO on a dry matter basis, slaughtered and the LTL was subjected to a 7 day chill storage. Neither diet nor post mortem ageing influenced (P > 0.05) antioxidant enzyme activities, chemical composition and cholesterol. Diet had no effect on the carbonyl content, free thiol content, water-holding capacity, tenderness, pH and glycogen. Oil-supplemented goats had higher (P < 0.05) C18:1 trans-11, C18:3n-3 and C20:5n-3, carotenoid, tocopherol and redness, and lower thiobarbituric acid reactive substances values than the control goats. Post mortem ageing decreased (P < 0.05) shear force and oxidative stability of chevon. No significant (P > 0.05) changes were found in the proportion of individual fatty acids throughout storage. Total polyunsaturated fatty acids (PUFA) decreased while total saturated fatty acids increased as storage progressed. Dietary BCPO enhanced n-3 PUFA without compromising the quality attributes of chevon.

Influence of cultivar and cutting date on the fatty acid composition of forage crops for grazing beef production in Argentina

AbstractThe fatty acid composition and total lipids of various forage crops at different cutting dates and seasons, which are used in forage grazing beef production in Argentina, were determined. Three experiments were carried out at the Agricultural Experimental Station of INTA, Anguil, La Pampa, Argentina Samples of alfalfa from three different cultivars with different dormancy groups (G4‐5, G6‐7 and G8‐9) and samples of ryegrasses Bill, Florida and Queue, wheats Charrua and Guapo, and triticale Don Santiago cultivars were taken at different cutting dates and analysed for total lipids and fatty acid composition. Significant differences on the fatty acid composition, the ratios 18:3n‐3/18:2n‐6 and polyunsaturated fatty acids (PUFA) due to cultivar, cutting date and season were found. Taking into account the importance of 18:2n‐6 and 18:3n‐3 fatty acids as substrates for the conjugated isomers of 18:2n‐6 (CLA) and n‐3 PUFA concentrations in beef, the fatty acid composition of forages needs to be considered in forage grazing beef production systems. Data variation in both total lipids and individual fatty acid proportions in forages should be taken into account to establish the potential to cultivate crops for a higher content of n‐3 PUFA and hence the opportunity to deliver more n‐3 PUFA and CLA into beef.

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources Two experiments were conducted to evaluate the effects of Lcarnitine supplementation on growth performance and epididymal adipose tissue fatty acid composition in rats fed diets containing different sources of fat. In the first study, rats were assigned to four groups receiving dietary treatments to evaluate the effects of supplementation with L-carnitine 0 ppm or L-carnitine 50 ppm in combination with two types of dietary fat: 100% soybean oil and a mixture of 50% soybean oil and 50% beef tallow. In the second study, the animals walked 2 h/day at a speed of 840 m/h. No significant differences were observed in the growth test results of each study. In experiment 1, the total saturated fatty acid (SFA) proportion was significantly higher in the L-carnitine 0 ppm 50% soybean oil and 50% beef tallow group than in the other groups. Dietary Lcarnitine suppressed the increase in the SFA proportion observed upon beef tallow consumption. In experiment 2, Lcarnitine decreased the SFA proportion and increased the monounsaturated fatty acid (MUFA) proportion. No interaction between the ingested fat type and L-carnitine supplementation on the proportions of individual fatty acids was observed, but Lcarnitine supplementation increased the C16:1 proportion and decreased the C18:0 proportion as a main effect in experiment 2. In conclusion, the current results suggest that dietary Lcarnitine decreased the SFA proportion in accordance with C18:0 utilization for energy production in walking rats.

Effects of parity, age at calving and stage of lactation on fatty acid composition of milk in Canadian Holsteins

Bilal, G., Cue, R. I., Mustafa, A. F. and Hayes, J. F. 2014. Effects of parity, age at calving and stage of lactation on fatty acid composition of milk in Canadian Holsteins. Can. J. Anim. Sci. 94: 401–410. The objectives of the present study were to study the effects of parity, age at calving and stage of lactation on individual fatty acids and fatty acid unsaturation indices in milk of Canadian Holsteins. One morning milk sample was collected from each of 3185 dairy cows between February and June 2010 from 52 commercial herds enrolled in the Quebec Dairy Production Centre of Expertise, Valacta. Individual fatty acid proportions (g 100 g⁻¹ of total fatty acids) were determined for each sample by gas chromatography. Editing for registration status, cow, sire and dam identification, breed, country, age at calving and stage of lactation reduced the data set to 2573 cows representing 46 herds. The statistical model included the fixed effects of parity, age at calving and stage of lactation each nested within parity and random effects of herd-year-season of calving and residual. First-parity cows had relatively higher proportions of beneficial unsaturated fatty acids, from a human health standpoint, and lower proportions of potentially undesirable saturated fatty acids in milk fat as compared with later parity cows. Milk fatty acid profile varied with stage of lactation. The proportions of short- and medium-chain fatty acids (C6:0 to C14:0) were low in the beginning of lactation and increased during the early part of lactation. Long-chain fatty acids (especially C18:0 and oleic acid) and unsaturation indices (C16, C18 and total) showed an opposite trend to that of short- and medium-chain fatty acids. The study showed that parity and lactation stage contribute to variation in bovine milk fat composition.

Effects of parity, age at calving and stage of lactation on fatty acid composition of milk in Canadian Holsteins

Bilal, G., Cue, R. I., Mustafa, A. F. and Hayes, J. F. 2014. Effects of parity, age at calving and stage of lactation on fatty acid composition of milk in Canadian Holsteins. Can. J. Anim. Sci. 94: 401–410. The objectives of the present study were to study the effects of parity, age at calving and stage of lactation on individual fatty acids and fatty acid unsaturation indices in milk of Canadian Holsteins. One morning milk sample was collected from each of 3185 dairy cows between February and June 2010 from 52 commercial herds enrolled in the Quebec Dairy Production Centre of Expertise, Valacta. Individual fatty acid proportions (g 100 g−1 of total fatty acids) were determined for each sample by gas chromatography. Editing for registration status, cow, sire and dam identification, breed, country, age at calving and stage of lactation reduced the data set to 2573 cows representing 46 herds. The statistical model included the fixed effects of parity, age at calving and stage of lactation each nested within...

Effect of Mn2+, Co2+ and H2O2 on biomass and lipids of the green microalga Chlorella vulgaris as a potential candidate for biodiesel production

The present study examined the effect of heavy metals (Mn2+ and Co2+) and hydrogen peroxide (H2O2) on biomass, lipid content and lipid productivity of Chlorella vulgaris. Manganese chloride at 2 μM, 10 μM and 12 μM increased the lipid content significantly by 14 %, 16 % and 15 %, respectively, above the corresponding controls after 8 days of incubation, resulting in a significant (18 %) increase in lipid productivity with respect to the control at 12 μM manganese chloride. All applied concentrations of cobalt nitrate increased the lipid content up to 25 % more than the corresponding controls. The optimum concentration of cobalt nitrate for high lipid productivity was 2.5 μM, which resulted in a 22 % increase in lipid productivity over the control. Furthermore, lipid productivity was increased significantly by 29 % over the control when 4 mM hydrogen peroxide was included in the culture medium. Additionally, the proportion of total saturated fatty acids extracted from Chlorella vulgaris treated with 12 μM manganese chloride, 2.5 μM cobalt nitrate and 4 mM hydrogen peroxide ranged between 40 % and 45 % of total fatty acids. The present study concluded that heavy metals and oxidative stress efficiently increased the lipid productivity of the promising biodiesel feedstock chlorophyte Chlorella vulgaris. In addition, the type and proportion of individual fatty acids meet the biodiesel standards.

Triacylglycerol composition of British bluebell (Hyacinthoides non-scripta) seed oil

Bluebell seeds were collected from the same location for five different growth periods (2006–2010). The composition of fatty acids in the triacylglycerols present in bluebell seeds was determined using 1H- and 13C NMR and GC-MS of fatty acid methyl esters with good agreement between the different methods of analysis for the proportion of individual fatty acids. The seed oil comprised 80% ω-9 monounsaturated (C18:1, C20:1, C22:1), 10% ω-6,9 biunsaturated (C18:2) and 10% saturated fatty acids (C16:0, C18:0, C20:0, C22:0). The oil contained 25% of fatty acids with 20 or 22 carbon chain length. Gondoic acid (C20:1) was present at 20% and there was a consistency in the composition of the seed oil for the different harvest years. Based on the composition of bluebell seed oil, possible future uses are suggested and the combination of bio refining bluebell seeds in tandem with conservation efforts is proposed.

A novel procedure for routine milk fat extraction based on dichloromethane

A novel method for the extraction of milk fat using dichloromethane (CH 2Cl 2)–ethanol was compared to the Rose-Gottlieb ( IDF Standard 1D, 1996) extraction procedure. The new extraction method consisted of a fast (approximately 30 min for 20 samples) and simple procedure involving direct mixing of raw cow milk samples with a dichloromethane–ethanol solution (2/1, v/v). The fatty acid (FA) proportions and FA groups as obtained through gas chromatography (GC) analysis of fatty acids methyl esters (FAME) showed that there was no relevant difference of the extraction procedure on the individual fatty acid proportions (%FAME). None of the main milk FA groups, such as the sum of monounsaturated (MUFA), polyunsaturated (PUFA), odd- and branched-chain (OBCFA) and saturated (SFA) FA showed any significant difference between the Rose-Gottlieb and dichloromethane methods. Total milk fat as gravimetrically determined did not differ between the two extraction procedures, although numerically a slightly lower amount (2.8% less) was extracted with the new procedure ( P = 0.919). In general, the new dichloromethane extraction method was found to be much faster, less hazardous to health (shorter exposure time) and more cost efficient (lower cost based on solvent price and amount used); overall, it is much more suitable for gas chromatography analysis of milk fatty acids than the older, more widely used Rose-Gottlieb extraction method.