Proportion Of Fatty Acids Research Articles

PSXIII-23 Effect of Methionine Inclusion in Mineral Mixture on Greenhouse Gas Production

Abstract The reduction in enteric methane production in cattle can have a rapid impact on global warming. Therefore, changes in the population of microorganisms in the rumen can significantly reduce the production of this greenhouse gas. This in vitro study aimed to evaluate the production of gases and methane with the inclusion of Suplemax mineral mixture containing methionine. The experiment was carried out under anaerobic conditions using ANKOM Gas Pressure Monitor bottles kept at 39 ºC containing artificial saliva, ruminal fluid, and two grams of a substrate from each treatment: (FE) Control, 1.75 g of Tifton hay 85 and 0.25 g of a mineral mix; and (FM) 1.75 g of hay and 0.25 g of Suplemax mineral mixture (Suplemento Nutrição Animal) containing 0.3% of methionine. Duplicate substrates and duplicate blanks were fermented for each treatment in two runs, with a total of four repetitions per treatment. The accumulated pressure resulting from the fermentation was measured automatically over 48 h using the Gas Monitor software connected to the ANKOM modules of each bottle. The conversion of pressure to gas volume was calculated as follows: Volume (mL) = 2.3932 + 3.4053 × pressure (R2 = 0.9146; n = 1.151). At the end of each run, a gas sample was collected from each bottle to measure methane concentration using gas chromatography. To obtain the methane production for every 100 mL of gas produced, the total volume of methane produced was multiplied by 100 and divided by the total gas production. Data were analyzed in a completely randomized design using analysis of variance (ANOVA) at α = 0.05. There was no significant effect on gas production with the inclusion of 0,3% of methionine (FE 37.77 mL vs FM 42.54 mL, P = 0.3175; Table 1). Methane production decreased from 22.74 to 18.15 mL (P = 0.0121) in the FM treatment compared with the FE treatment, representing a 20.18% decrease. Methane production for every 100 mL of gas decreased by 31.08% with the inclusion of methionine (FE 61.62 vs FM 42.47 mL, P = 0.0248). The inclusion of methionine in the mineral supplement contributes to a change in the molar proportion of short-chain fatty acids, increasing propiogenesis, that is considered a sink of hydrogen ions in the ruminal environment, which in turn inhibits methane production. Thus, the inclusion of Suplemax with hay reduced gas and methane production in vitro.

The Effect of a Diet Supplemented with Organic Minerals and l-Carnitine on Egg Production and Chemical Composition and on Some Blood Traits of Pheasant Hens (Phasianus colchicus)

The study aimed to determine the effect of replacing 75% of inorganic calcium, iron, zinc, and copper salts with organic forms (glycine chelates of these elements) with or without the addition of l-carnitine on some reproductive traits and the blood lipid and mineral profile, as well as mineral and fatty acid profile of pheasant egg yolk. The study was performed on three groups of pheasant hens using glycine chelates with calcitriol (group II) or analogical treatment with the addition of l-carnitine at the level of 100 mg/kg of feed (group III) instead of Ca, Fe, Cu, and Zn salts (control). The replacement of inorganic forms with glycinates contributed to an increase in the number of laid eggs with a concomitant lower share of rejected eggs. The supplementation of organic forms of minerals improved mineral absorption and bioavailability in blood serum as well as in the egg yolk of experimental groups. Egg yolk fat was characterized by a higher proportion of polyunsaturated fatty acids and a favorable ratio of PUFA ω-3/ω-6. The proposed nutritional supplementation of the pheasant’s diet might be a good strategy for increasing the nutritional reserves of poultry and improving their reproduction.

Enhanced seed yield, essential amino acids and unsaturated fatty acids in soybean seeds with phosphorus fertilizer supply

This study aimed to understand the role of phosphorus (P) in soybean yield and quality, particularly amino acids and fatty acids. Field trials were undertaken using 56 soybean genotypes, including 12 landraces, 36 commercial cultivars and 8 advanced breeding lines. The results showed the response of seed yield (+20%) to P supply was higher than the protein (+1.5%) and oil (–1.5%) content. Phosphorus supply explained 80.5%, 11.4% and 50.6% variation of seed yield, oil and protein content, respectively. Five out of eight essential amino acids were significantly increased with P supply. Phosphorus supply resulted in a significant increase in oleic acid but a decrease in linoleic acid, as well as a decrease in saturated and an increase in unsaturated fatty acids. Phosphorus supply accounted for 30.9% and 33.9% variation in essential and non-essential amino acids, and 5.1% and 27.9% variation in saturated and unsaturated fatty acids, respectively. We concluded (1) both yield and soybean seed quality can be improved with P fertilizer supply; (2) the seed nutritional quality improved by increasing the concentration of essential amino acids and proportion of unsaturated fatty acids. These findings emphasized the importance of P management guidance to simultaneously increase yield and food nutritional value.

Separated two-stage hydrothermal liquefaction of livestock manure for high-quality bio-oil with low-nitrogen content: Insights on nitrogen migration and evolution

The practical utilization of hydrothermal liquefaction (HTL)-derived bio-oil encounters limitations due to its high nitrogen (N) content, specifically when derived from protein-rich feedstock such as algae and livestock manure. In this study, a separated two-stage HTL (ST-HTL) was developed for producing bio-oil with high yield and low N-content. The main objective of this study was to reveal the N migration and evolution during the HTL process for a better understanding of the detailed mechanism. The separated two-stage HTL yielded the highest bio-oil, 32.90 wt%, with a maximum energy recovery of 68.47 %. In conventional HTL-derived bio-oil (280 °C), 38.85 % of N and 56.22 % of C (carbon) was transferred to the bio-oil, while 26.04 % of N and 61.34 % of C (carbon) in swine manure was transferred into the ST-HTL-derived bio-oil, which indicated a 32.83 % reduction in N-transfers and 8.35 % increase in C-transfers. GC–MS analysis revealed that the bio-oil from ST-HTL contained a higher proportion of fatty acids and a lower proportion of nitrogenous compounds compared to conventional HTL (280 °C). In addition, FT-ICR MS revealed that the ST-HTL-derived-bio-oil was more saturated than conventional HTL-derived bio-oil (280 °C). The underlying mechanism behind the increased bio-oil yield and reduced N content attained through ST-HTL are discussed in detail, thereby revealing its intrinsic merits. Thus, it is the first study to propose the N migration and evolution pathways during ST-HTL through detailed characterizations, thus, demonstrating its potential for improving the feasibility of processing high-protein livestock manure and promising practical applications.

Fatty acids, their proportions, ratios, and relations in the selected muscles of the thigh and roast beef

The study aimed to examine, compare, and statistically evaluate the quality of the beef thigh and roast beef muscle in terms of the profile of fatty acids in relation to human health. Musculus semimembranosus and m. quadriceps femoris of the thigh and m. longissimus dorsi of the roast beef were used for analysis to evaluate the fatty acid profile. Chemical analysis of the thigh and roast beef muscle samples was performed using Fourier transform infrared (FTIR) spectroscopy. The measured data were statistically processed according to descriptive characteristics, analysis of variance, and differences were tested using Scheffe´s test at a = 0.05. The SAS program package, version 8.2, was used to evaluate the results statistically. A statistically significant difference (p ≤0.05) was recorded in the dry matter proportion between m. quadriceps femoris and m. longissimus dorsi. A statistically significant difference was found in the intramuscular fat proportion, polyunsaturated fatty acid proportion, the ratio of polyunsaturated fatty acids to saturated fatty acids, the ratio of polyunsaturated fatty acids to monounsaturated fatty acids, as well as between m. semimembranosus and m. longissimus dorsi and between m. quadriceps femoris and m. longissimus dorsi. Strong, statistically significant (p ≤0.01, p ≤0.001) correlations were found mainly between intramuscular fat and polyunsaturated fatty acids, between intramuscular fat and the ratio of the polyunsaturated fatty acids to saturated fatty acids, between intramuscular fat and the ratio of polyunsaturated fatty acids to monounsaturated fatty acids. In conclusion, it was stated that the muscles of the thigh and roast beef of the young cattle are characterized by statistically significant differences in the proportion of fatty acids. The ratio of polyunsaturated fatty acids to saturated fatty acids meets the recommended values concerning maintaining the health of the food consumer. Still, the ratio of the n-6 to n-3 polyunsaturated fatty acids poses a risk concerning cardiovascular diseases.

Comparison of fat determination methods and analysis of fatty acids in tea

Comparative analysis of two method for determining fat and analysis of fatty acid content in tea samples. The content of freefatand total fat in tea was determined by Soxhlet extraction method and acid hydrolysis method, and the content of fatty acids were determined by gas chromatography. The composition and content of fatty acids in 21 tea samples from 5 regions were analyzed. The freefat content of tea determined by Soxhlet extraction method was significantly lower than that determined by acid hydrolysis method. The totalfat content in tea determined by acid hydrolysis method was consistent with the total amount of fatty acids determined by gas chromatography, and their content conformed to the logical relationshipsimultaneously. The totalfat content in tea ranged from 0.6 to 4.1 g/100 g, which in green tea, white tea, yellow tea, and black tea were 2.2, 1.8, 1.6 and 0.6 g/100 g, respectively. The content of free fat in tea was less than 58%, with 42%-80% of the fat existing in a bound form. The fatty acids in tea were mainly unsaturated fatty acids, accounting for 67.52%-99.03% of the total fatty acids. There were differences in the composition of fatty acids in different types of tea, with the proportion of unsaturated fatty acids in yellow tea accounting for 98.84% of the total fatty acids, which was significantly higher than that of green tea, white tea, and black tea. The fatty acids with high content in green tea(except Tang chi xiaolan tea, Bawangjian green tea and Liuxi yuye tea)were α-linoleic acid, linoleic acid, and palmitic acid. Theacid hydrolysis method is more suitable for the determination of fat in tea samples. The composition and content of fat and fatty acids in tea vary depending onfactors such as the type of tea and the degree of fermentation.

Regulatory mechanisms and cell membrane properties of Candida glycerinogenes differ under 2-phenylethanol addition or fermentation conditions.

The biosynthesis of 2-phenylethanol (2-PE) at high yields and titers is often limited by its toxicity. In this study, we describe the molecular mechanisms of 2-PE tolerance in the multi-stress tolerant industrial yeast, Candida glycerinogenes. They were different under 2-PE addition or fermentation conditions. After extracellular addition of 2-PE, C. glycerinogenes cells became rounder and bigger, which reduced specific surface area. However, during 2-PE fermentation C. glycerinogenes cells were smaller, which increased specific surface area. Other differences in the tolerance mechanisms were studied by analyzing the composition and molecular parameters of the cell membrane. Extracellular 2-PE stress resulted in down-regulation of transcriptional expression of unsaturated fatty acid synthesis genes. This raised the proportion of saturated fatty acids in the cell membrane, which increased rigidity of the cell membrane and reduced 2-PE entry to the cell. However, intracellular 2-PE stress resulted in up-regulation of transcriptional expression of unsaturated fatty acid synthesis genes, and increased the proportion of unsaturated fatty acids in the cell membrane; this in turn enhanced flexibility of the cell membrane which accelerated efflux of 2-PE. These contrasting mechanisms are mediated by transcriptional factors Hog1 and Swi5. Under 2-PE addition, C. glycerinogenes activated Hog1 and repressed Swi5 to upregulate erg5 and erg4 expression, which increased cell membrane rigidity and resisted 2-PE import. During 2-PE fermentation, C. glycerinogenes activated Hog1 and repressed Swi5 to upregulate 2-PE transporter proteins cdr1 and Acyl-CoA desaturase 1 ole1 to increase 2-PE export, thus reducing 2-PE intracellular toxicity. The results provide new insights into 2-PE tolerance mechanisms at the cell membrane level and suggest a novel strategy to improve 2-PE production by engineering anti-stress genes.

Fat, oil and grease wastewater and dishwashers: Uncovering the link to FOG deposition

Fats, oils, and grease (FOG) in wastewater generated by commercial food establishments can cause severe environmental damage if not adequately treated. Grease interceptors (GIs) are an effective solution to limit FOG disposal into the sewer, but their efficiency greatly depends on the wastewater's characteristics. This laboratory study examined the physical and chemical properties of synthetic FOG wastewater from handwashing sinks and dishwashers using cooked animal fats and oils, some food solids and the same amount of detergent to explore the impact of dishwashers on key FOG components that contribute to FOG depositions. Results showed that dishwasher-generated wastewater had a significant influence on fatty acid (FA) transformations, particularly in producing very long chain saturated FAs. Relative proportions of FAs revealed a considerable proportion of very long chain FAs, such as palmitoleic (C16:1), linoleic (C18:2), α-linolenic (C18:3), arachidic (C20:0), paullinic (C20:1), behenic (C22:0), erucic (C22:1), lignoceric (C24:0) and nervonic (C24:1), among which most were not highlighted in the real field FOG wastewater. These FAs may play a significant role in FOG solidification if not sufficiently removed before disposal to sewer. The study also found that dishwashers were able to break down FOG particles, creating smaller particles (75 % being ≤68.8 μm and 50 % being ≤7 μm), while handwashing sinks produced larger particles (50 % being ≤118 μm and 10 % being ≤7 μm and). Samples containing cooked animal fats were more likely to be fragmented into smaller sizes than cooking oils due to the impact of the dishwasher. Confocal microscopy analysis results were consistent with the particle sizes measured by laser diffraction. These distinct properties could serve as criteria for updating GI designs, limiting the amount of FOG and FAs disposed of in the sewer system and controlling solidification and blockages, which pose significant threats to the environment.

Gac (Momordica cochinchinensis Spreng.) oil supplementation mitigates cognitive decline in AlCl3-induced rats through the regulation of Alzheimer's disease markers and autophagy via gut-brain communication

Previous studies showed that oleic acid-rich camellia oil (Camellia oleifera Abel., CO) alleviates the cognitive impairment symptoms of Alzheimer's disease (AD). Gac oil (Momordica cochinchinensis Spreng., GO) is rich in β-carotene, lycopene, and oleic acid; no study has explored the effects of GO on AD. Accordingly, this study examined the effects of GO and CO on AD prevention in rats subjected to AlCl3 intragastric gavage. The results exhibited similar effects of GO, CO, and GO/CO supplementation on restraining AlCl3-induced brain RAGE/NF-κB signaling, proinflammatory cytokines, MDA, and AD markers by upregulating anti-inflammatory cytokines, antioxidative enzymes, and autophagy, which subsequently enhanced the clearance of Aβ1-42 and memory capacity. Gut microbiota composition increased the proportions of short-chain fatty acids (SCFAs)-producing [Eubacterium]_coprostanoligenes_group and Lactobacillus_johnsonii in the oil intake groups, which were positively correlated with anti-inflammatory, autophagy, and dementia mitigation. This compelling evidence implies that consuming GO and CO is a strategy for AD prevention.

Unlocking the potential of microalgae cultivated on wastewater combined with salinity stress to improve biodiesel production

Microalgae have the potential as a source of biofuels due to their high biomass productivity and ability to grow in a wide range of conditions, including wastewater. This study investigated cultivating two microalgae species, Oocystis pusilla and Chlorococcus infusionum, in wastewater for biodiesel production. Compared to Kühl medium, KC medium resulted in a significant fold increase in cellular dry weight production for both O. pusilla and C. infusionum, with an increase of 1.66 and 1.39, respectively. A concentration of 100% wastewater resulted in the highest growth for O. pusilla, with an increase in biomass and lipid content compared to the KC medium. C. infusionum could not survive in these conditions. For further increase in biomass and lipid yield of O. pusilla, different total dissolved solids (TDS) levels were used. Maximum biomass and lipid productivities were achieved at 3000 ppm TDS, resulting in a 28% increase in biomass (2.50 g/L) and a 158% increase in lipid yield (536.88 mg/g) compared to KC medium. The fatty acid profile of O. pusilla cultivated on aerated wastewater at 3000 ppm TDS showed a high proportion of desirable saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) for biodiesel production. Cultivating microalgae in wastewater for biodiesel production can be cost-effective, especially for microalgae adapted to harsh conditions. It could be concluded that O. pusilla is a promising candidate for biodiesel production using wastewater as a growth medium, as it has high biomass productivity and lipid yield, and its fatty acid profile meets the standard values of American and European biodiesel standards. This approach offers a sustainable and environmentally friendly solution for producing biofuels while reducing the environmental impact of wastewater disposal.

Effect of pomegranate seed oil on egg production, egg quality and yolk fatty acid deposition in laying hen.

Pomegranate seed oil (PSO) contains punicic acid as well as conjugated linolenic acid isomers, including α-eleostearic and catalpic acids, along with phytosterols, especially β-sitosterol, campesterol and stigmasterol, with lipotropic impact and egg fortifying effect in laying hens. The present experiment was designed to examine the effects of PSO on egg production, egg quality, blood lipids and yolk fatty acid deposition in laying hens. A total of 360 Hy-line laying hens (w-80), at 25 weeks of age, were randomly allotted to five dietary treatments in a completely randomized design during a 10-week period. Experimental treatments consisted of a basal diet or supplementation of 1, 2, 3 and 4gPSO/kg to basal diet. Performance indicators and fatty acid composition of egg yolk were evaluated during different experimental periods. Blood lipid attributes were evaluated at the end of the experiment. Dietary supplementation of 4gPSO/kg feed increased daily feed intake and egg production rate of laying hens (p<0.05). There was not any significant influence of experimental treatments on egg quality, whereas an increasing trend observed in egg yolk colour of hens received dietary graded levels of PSO. Dietary supplemental 4g/kgPSO increased the proportion of yolk poly-unsaturated fatty acid (PUFA) concentration (p<0.05). Furthermore, the PUFA to saturated fatty acid ratio increased after dietary supplementation of 1 or 4g/kgPSO (p<0.05). Serum concentration of cholesterol, triacylglycerol and low-density lipoprotein decreased in response to the supplementation of more than 3gPSO/kg in the feed (p<0.05). In conclusion, dietary supplementation with 4g/kgPSO improved production rate and decreased blood lipids in laying hens. Moreover, dietary supplemental PSO modified yolk fatty acid deposition without detrimental effects on the egg quality.

Failure of Cronobacter sakazakii to acquire direct and cross-protection against lethal stresses after exposure to sublethal ethanol

Abstract Cronobacter sakazakii may encounter subinhibitory concentrations of ethanol stress over its lifecycle. Bacterial tolerance to homologous or heterologous stress agents may be altered as a result of ethanol adaptive responses. Therefore, the tolerance of ethanol-exposed and control cells to subsequent lethal stresses was evaluated in the current work. It was discovered that sublethal ethanol exposure increased the susceptibility to lethal ethanol stress in C. sakazakii as determined by the Weibull model. Furthermore, sublethal ethanol concentration exposure in C. sakazakii did not lead to any cross-tolerance against other stressors such as benzalkonium chloride (120 mg/L), heat (55 °C), cold (4 °C), simulated gastric fluid (pH 3.0), osmotic stress (sorbitol, 0.75 g/mL), and desiccation stress. Analysis of zeta potential, scanning electron microscope, and surface-enhanced Raman spectroscopy spectra revealed that cellular injury and changes in cellular chemical composition may contribute to the reduced resistance of C. sakazakii after ethanol exposure. Furthermore, sublethal ethanol exposure resulted in an elevated proportion of unsaturated fatty acids (USFA), while reducing the proportion of saturated fatty acids (SFA) and the ratio of SFA to USFA. The developed inactivation models can serve as a valuable source of data to support quantitative microbial risk assessment. Moreover, a better understanding of the response of C. sakazakii to sublethal ethanol exposure may provide valuable insights into the prevention and control of C. sakazakii.

Adaptive laboratory evolution of a thermophile toward a reduced growth temperature optimum.

Thermophily is an ancient trait among microorganisms. The molecular principles to sustain high temperatures, however, are often described as adaptations, somewhat implying that they evolved from a non-thermophilic background and that thermophiles, i.e., organisms with growth temperature optima (TOPT) above 45°C, evolved from mesophilic organisms (TOPT 25-45°C). On the contrary, it has also been argued that LUCA, the last universal common ancestor of Bacteria and Archaea, may have been a thermophile, and mesophily is the derived trait. In this study, we took an experimental approach toward the evolution of a mesophile from a thermophile. We selected the acetogenic bacterium T. kivui (TOPT 66°C) since acetogenesis is considered ancient physiology and cultivated it at suboptimal low temperatures. We found that the lowest possible growth temperature (TMIN) under the chosen conditions was 39°C. The bacterium was subsequently subjected to adaptive laboratory evolution (ALE) by serial transfer at 45°C. Interestingly, after 67 transfers (approximately 180 generations), the adapted strain Adpt45_67 did not grow better at 45°C, but a shift in the TOPT to 60°C was observed. Growth at 45°C was accompanied by a change in the morphology as shorter, thicker cells were observed that partially occurred in chains. While the proportion of short-chain fatty acids increased at 50°C vs. 66°C in both strains, Adpt45_67 also showed a significantly increased proportion of plasmalogens. The genome analysis revealed 67 SNPs compared to the type strain, among these mutations in transcriptional regulators and in the cAMP binding protein. Ultimately, the molecular basis of the adaptation of T. kivui to a lower TOPT remains to be elucidated. The observed change in phenotype is the first experimental step toward the evolution of thermophiles growing at colder temperatures and toward a better understanding of the cold adaptation of thermophiles on early Earth.

Physiological and transcriptomic insights into sugar stress resistance in osmophilic yeast Zygosaccharomyces rouxii

The osmophilic yeast Zygosaccharomyces rouxii has attracted increasing attention for its ability to survive and grow in extremely high sugar environments. This trait determines its role in fermentation process and results in contamination in the food industry. However, the behavior of Z. rouxii in regulating cell metabolism to combat high sugar stress and the corresponding mechanism have not been completely elucidated. Here, the resistance strategies of Z. rouxii against high glucose stress were explored by physiological analysis at cell membrane level and transcriptomic analysis. Physiological analysis showed that under high glucose stress, colony transparency increased, cell volume decreased, which was accompanied by reduction in permeability and integrity of cell membrane and subsequent gradual recovering. Additionally, the proportion of ergosterol and unsaturated fatty acids in cell membrane significantly increased under high glucose stress. A comparison of transcriptome data showed that most of the obtained differentially expressed genes (DEGs) involved in ergosterol and linoleic acid synthesis pathways as well as cell wall integrity (CWI) and high osmolarity glycerol mitogen-activated protein kinase (HOG-MAPK) pathways, which was in line with the results of physiological data. Our results provided a theoretic basis to develop the process control for the production of high sugar foods.

Effects of dietary forage-to-concentrate ratio and forage type on milk phospholipids and fatty acid composition of polar lipids

The effects of grass silage and red clover silage on milk fatty acid (FA) composition are extensively studied, but little is known of their effects on minor lipid constituents of milk fat globule membrane. We investigated the effects of forage:concentrate (FC) ratio in grass silage-based diets and forage type (grass silage vs. red clover silage) on selected molecular species of milk phospholipids (PL) and the FA composition of PL. Ten multiparous Nordic Red cows were offered following dietary treatments: grass silage-based diets containing 70:30 (HG) or 30:70 (LG) FC ratio or a red clover silage-based diet (RC) comprising 50:50 FC ratio on a dry matter basis. The most abundant molecular species within the phosphatidylcholines was 16:0-18:1 phosphatidylcholine that was increased by 18% in HG compared with LG milk. Dietary treatments did not affect the relative proportion of 18:1-18:1+18:0-18:2 phosphatidylethanolamine that was the most prevalent species (ca. 44%-45%) in that class. We identified the d18:1-22:0 sphingomyelin as the most abundant sphingomyelin species that tended to increase in HG milk compared with LG. The FC ratio did not affect the relative proportions of saturated FA nor monounsaturated FA in PL, but the proportion of cis-9 18:1 was elevated in HG versus LG milk, whereas the proportion of 18:2n-6 was 50% higher in LG versus HG milk. The RC diet increased monounsaturated FA and 18:3n-3 levels in PL compared with grass silage-based diets and decreased the relative proportion of saturated FA. However, the RC diet did not affect the relative proportion of polyunsaturated FA in PL, although red clover silage typically increases the proportion of polyunsaturated FA in milk fat. This study provides valuable knowledge of the minor lipid components in milk on species level in relation to common feeding strategies in high-forage systems.

Associations between subclinical intramammary infection and milk fatty acid profile at the quarter level in Holstein cattle.

Mastitis, especially the subclinical form, is the most common economic and health problem in dairy cows. Little is known about changes in milk fatty acid (FA) composition according to infection/inflammation status of the mammary gland. The aim of this study was to investigate the associations between naturally occurring subclinical intramammary infection (IMI) from different pathogens, i.e. Streptococcus agalactiae, Staphylococcus aureus, Streptococcus uberis and Prototheca spp., and the detailed milk FA profile assessed at quarter level in Holstein cows. After an initial bacteriological screening (T0) on 450 Holstein cows reared in three dairy herds, we identified 78 cows positive at the bacteriological examination. These animals were followed up at the quarter level two weeks (T1) and six weeks (T2) after T0. In total, 600 single-quarter samples were obtained at T1 and T2. Individual FAs were determined using the gas chromatography analytical method. Investigated traits were 70 individual FAs, 12 FA groups, and six desaturation indices. The associations between subclinical IMI combined with somatic cell count (SCC) and milk FA profile were investigated using a hierarchical linear mixed model (i.e., observational unit was quarter within cow) with the following fixed effects: days in milk (DIM), parity, herd, SCC, bacteriological status (BACT, positive and negative), and the SCC × BACT interaction. The random effect of individual cow nested within herd, DIM and parity was used as the error term for the latter effects. The most significant associations were detected at T2. Notably, IMI reduced the proportions of individual short-chain FA, especially 4:0 and 6:0 (-14%), but increased the proportion of the most abundant medium-chain FA (MCFA), 16:0 (+4%). A reduction in the desaturation indices was observed mostly for 14:1 index (-9%), in line with the reduction in 14:1 (-10%). Somatic cell count significantly affected 14 individual FAs. In particular, samples with high SCC (≥200 000) had significantly lower proportions of 8:0, 10:0, 11:0, 12:0, and 13:0 compared with samples with low SCC (<200 000). Increasing SCC in animals positive at the bacteriological examination were associated with a reduction in total MCFA at T2 (while in negative animals, they remained constant across SCC classes), possible evidence that elongation of the FA chain from 11 to 16 carbons is affected by a combination of infection and SCC. This study showed that subclinical IMI and SCC are mainly associated with reductions in the synthesis of FA and the desaturation process in the mammary gland.

Impact of parity on the profile of fatty acids with potential importance for human health in camel (Camelus dromedarius) milk

The aim of the present study was to investigate the influence of parity on the proportion of fatty acids with potential health significance in camel milk fat. Milk samples were collected from four multiparous and four primiparous camels in intensive husbandry at mid-lactation stage. Fatty acid methyl esters were analysed by gas chromatography in conjunction with a flame ionisation detector. Parity had a significant effect on fat and total solids content (p&lt;0.05); mutiparous camels produced milk with lower fat and total solids content. In contrast, protein and ash content were not affected by parity (p&gt;0.05). Primipara camels produced milk richer (p&lt;0.05) in odd and branched chain fatty acids, monounsaturated fatty acids, C17:0, C15:0, omega-3 fatty acids, oleic acid, vaccenic acid and α-linolenic acid, while poorer (p&lt;0.05) for total short-chain fatty acids, total medium-chain fatty acids, total saturated fatty acids, C6:0, C10:0, C14:0, c9-C16:0, C16:0 and iso-C16:0. In addition, the desaturation index for C16, which is an indicator of Δ9-desaturase activity, and the atherogenicity index were lower in primiparous camels (p&lt;0.05). Parity had no effect on conjugated linoleic acid content (p&gt;0.05). Overall, the milk fat of primiparous camels appears to have a relatively high nutritional value, as it contained higher levels of beneficial fatty acids and lower levels of saturated fatty acids.

Pumpkin seed oil: A comprehensive review of extraction methods, nutritional constituents and health benefits.

Pumpkin seed oil (PSO), a rich source of nutrient contents, is extracted from the seeds of different pumpkin varieties for food and medicine industries. Accordingly, this article was designed to provide an evidence-based review of the literature, with the purpose of achieving practical conclusions involved the extraction technologies, nutritional properties, and validated biological activities of PSO. From the previous literatures, PSOs contain a large proportion of unsaturated fatty acids, with linoleic acid as the main component, and an amount of tocopherol, phytosterol, and phenolic acids. Some differences in the yield, composition and physicochemical properties of PSO can be associated with the pumpkin's cultivars and the extraction methods. Some novel technologies involved in supercritical fluid extraction, enzyme-assisted aqueous extraction, ultrasound-assisted extraction have been gradually replacing the conventional technologies as the most promising method which promote safe, non-polluting and effective recovery of PSO. This healthy vegetable oil was reported by several in vitro and in vivo studies to have potential protective roles in oxidative stress, inflammation, cancer, and cardiovascular diseases. This article is protected by copyright. All rights reserved.

Developing a soft margarine with modified fatty acid profile having low trans fatty acids

SummaryA healthy diet cannot comprise only one single natural fat or oil. The American Health Association (AHA) recommends for consumption a balanced fatty acid ratio of approximately 1:1:1 for PUFA: MUFA: SFA. Such proportions of fatty acids can promote health and reduce the level of blood LDL‐cholesterol. In this study, we developed a margarine formulation with modified fatty acid profile and low trans fatty acids. For formulation of a margarine with PUFA: MUFA: SFA ratio of 1:1:1, having equal amounts of poly‐ and mono‐unsaturated and saturated fats, the data on fatty acid profiles on vegetable oils indicated that the proportions palm stearin 30%, rice bran oil 40%, and soybean oil 30% was appropriate. The oil mixture gave the PUFA: MUFA: SFA ratio 1.00:0.97:1.00 and a trans fatty acid level below the limit recommended by the US FDA, namely less than 0.5 mg/serving size. The developed margarine had the higher rating for general appearance (6.7–8.9), when compared to a commercial brand. Its peroxide value was 6.19 ± 0.83 mEq/kg fat after storage for 90 days at refrigerated 4–5 °C temperature, which is below the FDA standard limit of 10.0 mEq/kg fat.

Effect of metabolic activity of lactic acid bacteria and propionibacteria on cheese protein digestibility and fatty acid profile

This study aimed at investigating the influence of different variants of bacterial starter cultures on the metabolism of the bacteria used, cheese protein digestibility, and fatty acid profile. The results revealed that lactic acid bacteria had a significant effect on the proportions of fatty acids in cheeses, with saturated fatty acids being predominant in in all cheese variants. Fatty acid proportions are complex and depend on the type of cheese culture and monoculture used. Additionally, the analysis of fatty acid composition showed variations in the proportion of saturated and unsaturated fatty acids, impacting the values of atherogenic and thrombogenic indices. Notably, the atherogenic index was highest in samples of mature cheeses obtained from a typical mesophilic cheese culture, whereas it was lowest in samples of fresh milk and mature cheeses obtained from a mesophilic cheese culture and monocultures of Lacticaseibacillus casei and Propionibacterium. The study also highlighted the influence of lactobacilli on the content of available free lysine, glycine, and methionine in cheese proteins. Mature cheeses obtained with Propionibacterium and L. casei starter cultures exhibited higher free lysine and glycine content compared with fresh cheeses and those obtained solely with the cheese culture. Additionally, mature cheeses obtained with starter cultures of mesophilic cheese culture, Propionibacterium, and L. casei had the highest free methionine content. Based on these findings, it is evident that the choice of cheese making cultures and monocultures can significantly affect the fatty acid composition and amino acid content of cheese and fresh milk, potentially bearing important health implications.