Fatty Acids C18 Research Articles

Capillary zone electrophoresis for fatty acids with chemometrics for the determination of milk adulteration by whey addition

Adulteration of milk with whey is difficult to detect because these two have similar physical and chemical characteristics. The traditional methodologies to monitor this fraud are based on the analysis of caseinomacropeptide. The present study proposes a new approach to detect and quantify this fraud using the fatty acid profiles of milk and whey. Fatty acids C14:0, C16:0, C18:0, C18:1, C18:2 and C18:3 were selected by gas chromatography associated with discriminant analysis to differentiate milk and whey, as they are present in quite different amounts. These six fatty acids were quantified within a short time by capillary zone electrophoresis in a set of adulterated milk samples. The correlation coefficient between the true values of whey addition and the experimental values obtained by this technique was 0.973. The technique is thus useful for the evaluation of milk adulteration with whey, contributing to the quality control of milk in the dairy industry.

Isolation, Identification and Characteristics of a Rhodopseudomonas with High Ammonia-nitrogen Removal Efficiency

A strain of photosynthetic bacterium named psb1 capable of ammonia-nitrogen degradation was isolated from a swamp in Yunnan. The psb1 was similar to Rhodopseudomonas sp. according to its cell morphological properties and absorption spectrum analysis of living cells. The alignment result of 16S rDNA amplification sequence with specific primers of photosynthetic bacteria showed that the homology between strain psb1 and Rhodopseudomonas sp. was 99%, and the alignment results of protein sequences of bacterial chlorophyll Y subunit showed that the strain psb1 and Rhodopseudomonas palustris were the most similar, with a similarity of 99%. But there was a great difference in the biological properties of the strains psb1 and Rhodopseudomonas palustris according to physiological biochemical characteristics and main fatty acid analysis. For example, strain psb1 could not utilize glucose and mannitol as carbon source, and had specific fatty acid C18:1ω6c. The results of single factor test showed that:the optimal growth was obtained at pH 7.0 and 40℃, the optimal nitrogen source was yeast extract. The optimal conditions for ammonia nitrogen biodegradation were as following:anaerobic, light, initial pH 6.0-7.0, temperature 30℃, inoculation volume 0.4%. Under that cultural condition, the degradation rate of ammonia nitrogen in wastewater could reach 99%. The results indicated that strain psb1 might be a novel bacterium in genus Rhodopseudomonas with high ammonia removal efficiency, and can be applied in the bioremediation of polluted landscape water.

Planomonospora corallina sp. nov., isolated from soil

A novel actinomycete strain, A-T 11038T, was isolated from bamboo rhizospheric soil collected in Thailand. Based on a polyphasic approach, the novel strain was characterized as a member of the genus Planomonospora, which developed cylindrical to clavate sporangia containing a single motile spore on aerial mycelium. The 16S rRNA gene sequence and phylogenetic analysis indicated that strain A-T 11038T was closely related to Planomonospora sphaerica JCM 9374T (98.82 %), P.lanomonospora parontospora subsp. parontospora NBRC 13880T and P.parontospora subsp. antibiotica JCM 3094T (98.54 %), Planomonospora alba JCM 9373T (98.41 %) and Planomonospora venezuelensis JCM 3167T (97.51 %). The DNA-DNA relatedness values that distinguished strain A-T 11038T from the most closely related species were below 45 %. The novel strain contained meso-diaminopimelic acid in cell-wall hydrolysates, and rhamnose, ribose, madurose and glucose in whole-cell hydrolysates. The predominant menaquinone was MK-9(H2). The diagnostic phospholipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylinositol and aminophosphoglycolipids. The predominant cellular fatty acids were unsaturated fatty acids C17 : 1 and C16 : 1 and saturated fatty acid C16 : 0. The G+C content of the genomic DNA was 73.5 mol%. Following the evidence obtained using a polyphasic approach, the novel strain is proposed as a representative of a novel species to be named Planomonospora corallina sp. nov. The type strain is A-T 11038T (=BCC 67829T=TBRC 4489T=NBRC 110609T).

Effects of automatic cluster removal and feeding during milking on milking efficiency, milk yield and milk fat quality.

In order to increase milking efficiency, the effects of two different cluster take-off levels (200 and 800 g/min) and feeding vs. not feeding during milking were tested in a Latin square design study including 32 cows. Milk yield, milking time, milk flow and milking interval were measured and milk samples were analysed for gross composition, sodium and potassium concentration, free fatty acid (FFA) content, milk fat globule (MFG) size, MFG membrane (MFGM) material and fatty acid composition. Residual milk was harvested to evaluate udder emptying. Increasing the take-off level from 200 to 800 g/min at the whole udder level decreased milking time and increased harvest flow. Udder emptying decreased slightly, but there were no effects on milk yield, FFA content or MFGM. There were interactive effects of take-off level and feeding during milking on content of fatty acids C4:0, C6:0, C16:0, C18:3(n-3) and C20:0. Feeding during milking increased milk yield per day and decreased milking interval. Sodium and potassium concentrations in milk were unaffected by treatments, indicating no loss of tight junction integrity. From these results, it is clear that feeding during milking should be used to increase milk yield and improve milking efficiency, regardless of take-off level used, and that the effect of feeding is more pronounced when a low take-off level is used. Feeding seemed to counteract the effects of the low take-off level on milking time and milking interval. Low take-off levels can therefore be used in combination with feeding.

Fatty acid compositional changes during the embryonic development of the swimming crab, Portunus pelagicus (Portunidae: Decapoda)

The fatty acid composition, moisture, and total lipid of the eggs from the swimming crab, Portunus pelagicus, at three different embryonic stages (within 24 h, during the eye placode stage and the final heart beat stage), were measured. Results showed that the moisture and lipid content significantly increased and decreased (p < 0.05), respectively, as the stages progressed. The most prevalent fatty acids that were initially deposited included C16:0, C18:1n-9, and C18:0, while the most consumed fatty acids were C22:5n-6, C22:5n-3, and C20:1n-7. Among the major fatty acid groups, polyunsaturated fatty acids (PUFA) and long-chain PUFA (LC-PUFA) were consumed more than saturated fatty acids and significantly more (p < 0.05) than monounsaturated fatty acids (p < 0.05). Meanwhile, n-3 PUFA was deposited in significantly higher amounts (p < 0.05) than n-6 PUFA, but both were consumed at similar amounts at 43.4% and 41.3%, respectively. The relatively low amount of C20:5n-3 and C22:6n-3 consumption may indicate these fatty acids were conserved, while the essential fatty acids C18:3n-3 and C18:3n-6 were consumed at high amounts. These findings may have implications for broodstock nutrition in order to formulate a well-balanced diet.

Front cover: Exploring the association of dairy product intake with the fatty acids C15:0 and C17:0 measured from dried blood spots in a multipopulation cohort: Findings from the Food4Me study

Front cover: Exploring the association of dairy product intake with the fatty acids C15:0 and C17:0 measured from dried blood spots in a multipopulation cohort: Findings from the Food4Me study

Quantification of Seed Oil Content and Fatty Acid Profile of Jatropha cucas L. from Guizhou, China

&lt;p class="1Body"&gt;The methyl esters of fatty acids composition of the oil from &lt;em&gt;jatropha curcas&lt;/em&gt; seeds were analyzed by gas chromatography-mass spectrometer GC-MS. Fourteen components were found to be representative with 99.52% of the total content of seed oils. The main constituents were unsaturated fatty acids (71.93%) and saturated fatty acids (27.59%). For the saturated fatty acids composition such as palmitic and stearic acid, the rate was 15.80% and 10.79%, respectively. Linoleic acid (39.58%) and oleic acid (30.41%) were obtained in highest concentration among the unsaturated fatty acids identified in the seeds oil of &lt;em&gt;Jatropha curcas&lt;/em&gt; from Guizhou. This value also justifies the fluidity of the oil at room temperature. A high percentage of polyunsaturated fatty acids (39.58%) and a slightly lower rate of monounsaturated fatty acids (32.35%) were also observed. The seed oils profile of Guizhou &lt;em&gt;Jatropha curcas&lt;/em&gt; presents the desirable fatty acid C14 to C18 and interesting features for the biodiesel production.&lt;/p&gt;

Does overwinter temperature affect maternal body composition and egg traits in yellow perch Perca flavescens?

Female yellow perch Perca flavescens exposed to three overwinter temperature regimes (4, 8 and 13° C) for 150 days spawned in markedly different proportions upon spring warming (37% of females in 4° C v. 64 and 91% in 8 and 13° C treatments, respectively), but exhibited no differences in fecundity, egg size or egg lipid content. Females held at 4° C also exhibited less within-clutch egg size variation than females held at 13° C. Moreover, eggs differed among temperature treatments in the overall proportions of 18 fatty acids, with the colder treatments resulting in potentially higher quality eggs containing more of the unsaturated fatty acids C16:1, C22:6-n3 and C18:2 cis. Female somatic condition also varied with temperature. Maternal somatic growth and protein content increased while lipid content decreased in 13° C compared to the colder treatments. There were, however, no differences among treatments in the fatty acid composition of maternal muscle. These results suggest that the temperatures experienced during winter may be less influential to P. flavescens egg size or number, which may exhibit relatively little plasticity in this species, but can alter both the number of females that spawn and the overall composition of eggs and maternal somatic tissues, which may have implications for future reproductive success.

Effects of the diacylglycerol o-acyltransferase 1 (DGAT1) K232A polymorphism on fatty acid, protein, and mineral composition of dairy cattle milk

Several studies have described associations between the diacylglycerol o-acyltransferase 1 (DGAT1) K232A polymorphism and routinely collected milk production traits but not much is known about effects of the DGAT1 polymorphism on detailed milk composition. The aim of this study was to estimate effects of the DGAT1 polymorphism on milk fatty acid, protein, and mineral composition. We looked for effects that were significant and consistent in Danish Holstein Friesian (HF), Danish Jersey, and Dutch HF as these are likely to be true effects of the DGAT1 K232A polymorphism rather than being effects of linked loci. For fatty acid composition, significant and consistent effects of the DGAT1 polymorphism were detected on C14:0, C16:0, C15:0, C16:1, C18:1 cis-9, conjugated linoleic acid (CLA) cis-9,trans-11, C18:2 cis-9,cis-12, and C18:3 cis-9,cis-12,cis-15 content (percent by weight, wt/wt %). For C16:0, C16:1, and C18:1 cis-9, the DGAT1 polymorphism explained more than 10% of the phenotypic variation. Significant effects on milk protein composition in Dutch HF could not be confirmed in Danish Jersey or Danish HF. For mineral content, significant and consistent effects of the DGAT1 polymorphism on calcium, phosphorus, and zinc were detected. In the Dutch HF population, the contribution of the DGAT1 K232A polymorphism to phenotypic variance was 12.0% for calcium, 8.3% for phosphorus, and 6.1% for zinc. Different from effects on fatty acid composition, effects of the DGAT1 polymorphism on yields of long-chain fatty acids C18:1 cis-9, CLA cis-9,trans-11, C18:2 cis-9,cis-12, and C18:3 cis-9,cis-12,cis-15 were not significant. This indicates that effects of DGAT1 on these fatty acids are indirect, not direct, effects: DGAT1 affects de novo synthesis of fatty acids and, consequently, the contribution of the long-chain fatty acids to total fat is decreased. In addition, effects of the DGAT1 polymorphism on yields of Ca, P, and Zn were not significant, which indicates that effects on these minerals are the result of indirect rather than direct effects of DGAT1: effects on calcium, phosphorus, and zinc content can be explained by effects of DGAT1 on milk volume. The reported effects of the DGAT1 polymorphism on fatty acid and mineral composition of milk are substantial and therefore relevant for milk quality.

Celeribacter persicus sp. nov., a polycyclic-aromatic-hydrocarbon-degrading bacterium isolated from mangrove soil.

A Gram-stain-negative, mesophilic bacterial strain, designated SBU1T, which degrades polycyclic aromatic hydrocarbons was isolated from the sediments of the mangrove forests of Nayband Bay in the Iranian Persian Gulf during a bioremediation experiment. The 16S rRNA gene sequence of strain SBU1T exhibited highest similarities with Celeribacter indicus P73T (98.52%) and Celeribacter neptunius H 14T (97.05%). Phylogenetic analysis, based on 16S rRNA gene sequences, demonstrated that strain SBU1T fell within a cluster consisting of the type strains of species of the genus Celeribacter and formed a stable clade with C. indicus P73T in trees generated with three algorithms. The fatty acid profile of strain SBU1T consisted of the major fatty acids C18:1ω7c/ω6c and C18:1ω7c 11-methyl. The major compounds in the polar lipid profile were one phosphatidylglycerol and four unidentified phospholipids. The quinone system exclusively comprised ubiquinone (Q-10). The DNA G+C content was 60.4 mol%. A combination of phylogenetic analysis, DNA-DNA hybridization estimation, average nucleotide identity results and differential phenotypic and chemotaxonomic characteristics demonstrated that strain SBU1T could be distinguished from its close relatives. Therefore, strain SBU1T is considered to represent a novel species of the genus Celeribacter for which the name Celeribacter persicus sp. nov. is proposed. The type strain is SBU1T (=MCCC 1A00672T=DSM 100434T).

Exploring the association of dairy product intake with the fatty acids C15:0 and C17:0 measured from dried blood spots in a multipopulation cohort: Findings from the Food4Me study.

The use of biomarkers in the objective assessment of dietary intake is a high priority in nutrition research. The aim of this study was to examine pentadecanoic acid (C15:0) and heptadecanoic acid (C17:0) as biomarkers of dairy foods intake. The data used in the present study were obtained as part of the Food4me Study. Estimates of C15:0 and C17:0 from dried blood spots and intakes of dairy from a Food Frequency Questionnaire were obtained from participants (n = 1180) across seven countries. Regression analyses were used to explore associations of biomarkers with dairy intake levels and receiver operating characteristic analyses were used to evaluate the fatty acids. Significant positive associations were found between C15:0 and total intakes of high-fat dairy products. C15:0 showed good ability to distinguish between low and high consumers of high-fat dairy products. C15:0 can be used as a biomarker of high-fat dairy intake and of specific high-fat dairy products. Both C15:0 and C17:0 performed poorly for total dairy intake highlighting the need for caution when using these in epidemiological studies.

Lipid composition and structural characteristics of bovine, caprine and human milk fat globules

Milk fat is widely accepted to be the major nutrient in human milk. Commercial infant formulas are usually based on mammalian milk such as bovine or caprine milk, but the differences in milk fat globules (MFGs) between human, bovine and caprine milk remain unclear. We showed that saturated fatty acid content was higher in bovine and caprine MFGs (>60%) than in human MFG (<40%), but that content of the unsaturated fatty acids C18:2 in human MFG was >7 times higher than in bovine and caprine MFGs. The cholesterol content of human milk was ∼20% higher than that of bovine and caprine milk. Triacylglycerol molecular species and polar lipids also differed between bovine, caprine and human MFGs. Confocal laser scanning microscopy images of MFGs revealed that the shape of the liquid-ordered domains varied by species.

The association between diet and glucocorticoid treatment in patients with SLE

BackgroundSome studies suggest that the risk for and severity of systemic lupus erythematosus (SLE) can be modified by certain nutrients. The aim of this study was to investigate the association...

The phylogenetic theory of general pathology. The becoming of function of at mitochondria at symbiosis of bacterial cells and archaea. Inconsistency of Randle cycle, regulation metabolism of fatty acids and glucose by insulin.

The implementation of Randle rule is not a cycle; fatty acids C4 - ketone bodies at interrelationships with glucose metabolite - pyruvate regulate production of mitochondria of acetyl-KoA by induction of substrate and its conversion in Krebs cycle, reactions of respiratory chain, oxidative phosphorylation and formation of ATP. In phylogenesis, the early substrate for formation of ATP by mitochondria is acetyl-KoA from C4 fatty acids 4; this is alternative A of induction by substrate adopted from archaea. The alternative B of induction in bacteria is based on synthesis of acetyl-KoA by mitohondria from pyruvate developed in cytosol from exogenous glucose. The insulin is late activator of absorption by glucose cells in phylogenesis; using induction by substrate, insulin inhibits absorption of fatty acids by cells and specifically activates absorption of glucose by them. The insulin activates absorption of glucose only by insulin-dependent cells by force of decreasing of "bioavailability" of fatty acids. These cells are preferred to be metabolize by mitochondria from times of archaea. The insulin, blocking lipolysis in insulin-dependent adipocytes "forces" mitochondria, instead of formation of acetyl-KoA from fatty acids, to produce it from pyruvate at activation of glycolysis and pyruvate-dehydrogenased complex. Under effect of insulin, mitochondria form acetyl-KoA and synthesize ATP from oleic mono-saturated fatty acids but not from palmitic saturated fatty acids. The kinetic parameters of second reaction and formation of ATP per unit of time (effectiveness) are much higher than in first reaction. The effectiveness of i9mplementation of alternative A in synthesis of ATP, kinetic parameters of production of acetyl-KoA in mitochondria in alternative A are more effective than in case of alternative B and metabolic conversion of glucose. The syndrome of resistance to insulin is, at the first place, pathology of metabolism of fatty acids and only in the second place metabolism of glucose. The incapacity of insulin to block lipolysis in the phylogenetically earlier visceral fatty cells is the basis of resistance.

Effect of oxytocin on milk proteins and fatty acid profile inSahiwal cows during lactation periods

Bovine milk, a rich source of proteins and fatty acids, has a beneficial impact on physicochemical and organoleptic properties. The current study was planned to identify oxytocin's effects on protein and fatty acid profiles of cow milk (the Sahiwal breed) at various lactation stages (early, middle, and late) under a controlled atmosphere and feeding inputs. Examination of milk protein and fatty acid profiles by urea polyacrylamide gel electrophoresis and gas chromatography-mass spectrometry respectively revealed the significant effect (P < 0.01) of oxytocin during the cow's lactation stages. In electrophoretic patterns, casein (αs1-CN, αs2-CN, β-CN, and k-CN) and whey protein fractions (Ig, BSA, β-Lg, and α-La) appeared as low-intensity bands in oxytocin-injected milk when compared to the control. Reductions in concentrations of fatty acids C16:0 (25.00%) and C18:1 (21.60%) were observed in oxytocin-treated milk as compared to the control group (29.30% and 29.10%, respectively) at late lactation.

Genetic and environmental relationships of detailed milk fatty acids profile determined by gas chromatography in Brown Swiss cows

The aim of this study was to characterize the profile of 47 fatty acids, including conjugated linoleic acid (CLA), 13 fatty acid groups, and 5 Δ9-desaturation indices in milk samples from Brown Swiss cows. The genetic variation was assessed and the statistical relevance of the genetic background for each trait was evaluated using the Bayes factor test. The additive genetic, herd-date, and residual relationships were also estimated among all single fatty acids and groups of fatty acids. Individual milk samples were collected from 1,158 Italian Brown Swiss cows and a detailed analysis of fat percentages and milk fatty acid compositions was performed by gas chromatography. Bayesian animal models were used for (co)variance components estimation. Exploitable genetic variation was observed for most of the de novo synthesized fatty acids and saturated fatty acids, except for C4:0 and C6:0, whereas long-chain fatty acids and unsaturated fatty acids (including CLA) were mainly influenced by herd-date effects. Herd-date effect explained large portions of the total phenotypic variance for C18:2 cis-9,cis-12 (0.668), C18:3 cis-9,cis-12,cis-15 (0.631), and the biohydrogenation and elongation products of these fatty acids. The desaturation ratios showed higher heritability estimates than the individual fatty acids, except for CLA desaturation index (0.098). Among the medium-chain fatty acids, C12:0 had greater heritability than C14:0 (0.243 vs. 0.097, respectively). Both C14:0 and C16:0 showed negative additive genetic correlations with the main monounsaturated and polyunsaturated fatty acids of milk fat, suggesting that their synthesis in the mammary gland may be influenced by the presence of unsaturated fatty acids. No correlation was observed between C4:0 and the other short-chain fatty acids (except for C6:0), confirming the independence of C4:0 from de novo mammary fatty acid synthesis. Among the genetic correlations dealing with potentially beneficial fatty acids, C18:0 was positively correlated with vaccenic and rumenic acids and negatively with linoleic acid. Finally, fatty acids C6:0 through C14:0 showed relevant correlations due to unknown environmental effects, suggesting the potential existence of genetic variances in micro-environmental sensitivity. This study allowed us to acquire new knowledge about the genetic and the environmental relationships among fatty acids. Likewise, the existence of genetic variation for most of de novo synthetized fatty acids and saturated fatty acids was also observed. Overall, these results provide useful information to combine feeding with genetic selection strategies for obtaining a desirable milk fatty acids profile, depending on the origin of fatty acids in milk.

Biomarkers of Ectopic Fat Deposition: The Next Frontier in Serum Lipidomics.

Strong evidence suggests that ectopic fat rather than fat mass per se drives risk for type 2 diabetes. Nonetheless, biomarkers of ectopic fat have gone unexplored. To determine the utility of serum lipidomics to predict ectopic lipid deposition. Cross-sectional. The Clinical Translational Research Center at the University of Colorado Anschutz Medical Campus. Endurance-trained athletes (n = 15, 41 ± 0.9 y old; body mass index 24 ± 0.6 kg/m(2)) and obese people with or without type 2 diabetes (n = 29, 42 ± 1.4 y old; body mass index 32 ± 2.5 kg/m(2)). Blood sampling and skeletal muscle biopsy. Multivariable models determined the ability of serum lipids to predict intramuscular (im) lipid accumulation of triacylglycerol (TAG), diacylglycerol (DAG), and ceramide (liquid chromatography tandem mass spectroscopy). Among people with obesity, serum ganglioside C22:0 and lactosylceramide C14:0 predicted muscle TAG (overall model R(2) = 0.48), whereas serum DAG C36:1 and free fatty acid (FFA) C18:4 were strong predictors of muscle DAG (overall model R(2) = 0.77), as were serum TAG C58:5, FFA C14:2 and C14:3, phosphotidylcholine C38:1, and cholesterol ester C24:1 to predict muscle ceramide (overall model R(2) = 0.85). Among endurance-trained athletes, serum FFA C14:1 and sphingosine were significant predictors of muscle TAG (overall model R(2) = 0.81), whereas no models could predict intramuscular DAG or ceramide in this group. Different serum lipids predict intramuscular TAG accumulation in obese people vs athletes. The ability of serum lipidomics to predict intramuscular DAG and ceramide in insulin-resistant humans may prove a new biomarker to determine risk for diabetes.

Engineering Rhodosporidium toruloides with a membrane transporter facilitates production and separation of carotenoids and lipids in a bi-phasic culture.

The oleaginous yeast Rhodosporidium toruloides has great biotechnological potential. It accumulates a high amount of lipids which can be used for biofuels and also produces carotenoids which are valuable in the food and pharmaceutical industry. However, the location of these two hydrophobic products in the cell membrane prohibits its efficient harvesting and separation. Here, the transporter Pdr10 was engineered into R. toruloides and cultured in two-phase media containing oil. This enabled the production and in situ export of carotenoids into the oil and concurrent separation from intracellular lipids in the cells. When Pdr10 strain was cultured in the two-phase media, carotenoids and fatty acids yield increased from 1.9 to 2.9 μg/mg and 0.07 to 0.09 mg/mg, respectively. A total of 1.8 μg/mg carotenoids was exported by Pdr10 strain, as compared to 0.3 μg/mg in the wild type. In the Pdr10 strain, the composition of carotenoids and fatty acid it produced also changed. Torulene became the major carotene produced instead of torularhodin. Also, the unsaturated fatty acid C18:2 became the dominant fatty acid produced instead of the saturated C16:0, which was similar to the grape seed oil used in the two-phase media. This indicated that oil was being consumed by the cells, which was supported by the increased intracellular glycerol levels detected by gas chromatography-mass spectrometry (GC-MS). Our approach represents an easy and greener extraction method which could serve to increase the yield and facilitate separation of carotenoids and fatty acids.

Deep sequencing shows microRNA involvement in bovine mammary gland adaptation to diets supplemented with linseed oil or safflower oil.

BackgroundBovine milk fat composition is responsive to dietary manipulation providing an avenue to modify the content of fatty acids and especially some specific unsaturated fatty acid (USFA) isomers of benefit to human health. MicroRNAs (miRNAs) regulate gene expression but their specific roles in bovine mammary gland lipogenesis are unclear. The objective of this study was to determine the expression pattern of miRNAs following mammary gland adaptation to dietary supplementation with 5 % linseed or safflower oil using next generation RNA-sequencing.MethodsTwenty-four Canadian Holstein dairy cows (twelve per treatment) in mid lactation were fed a control diet (total mixed ration of corn:grass silages) for 28 days followed by a treatment period (control diet supplemented with 5 % linseed or safflower oil) of 28 days. Milk samples were collected weekly for fat and individual fatty acid determination. RNA from mammary gland biopsies harvested on day-14 (control period) and on days +7 and +28 (treatment period) from six randomly selected cows per treatment was subjected to small RNA sequencing.ResultsMilk fat percentage decreased significantly (P < 0.001) during treatment with the two diets as compared to the control period. The individual saturated fatty acids C4:0, C6:0, C8:0, C14:0 and C16:0 decreased significantly (P < 0.05) while five USFAs (C14:1, C18:1n11t, C20:3n3, C20:5n3 and CLA:t10c12) increased remarkably (P < 0.05) in response to both treatments. Analysis of 361 million sequence reads generated 321 known bovine miRNAs and 176 novel miRNAs. The expression of fourteen and twenty-two miRNAs was affected (P < 0.05) by linseed and safflower oil treatments, respectively. Seven miRNAs including six up-regulated (bta-miR-199c, miR-199a-3p, miR-98, miR-378, miR-148b and miR-21-5p) and one down-regulated (bta-miR-200a) were found to be regulated (P < 0.05) by both treatments, and thus considered core differentially expressed (DE) miRNAs. The gene targets of core DE miRNAs have functions related to gene expression and general cellular metabolism (P < 0.05) and are enriched in four pathways of lipid metabolism (3-phosphoinositide biosynthesis, 3-phosphoinositide degradation, D-myo-inisitol-5-phosphate metabolism and the superpathway of inositol phosphate compounds).ConclusionOur results suggest that DE miRNAs in this study might be important regulators of bovine mammary lipogenesis and metabolism. The novel miRNAs identified in this study will further enrich the bovine miRNome repertoire and contribute to understanding mammary gland biology.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-1965-7) contains supplementary material, which is available to authorized users.

Kosakonia pseudosacchari sp. nov., an endophyte of Zea mays

A beige pigmented bacterial strain (JM-387T), isolated from field-grown corn root tissue, Tallassee, Alabama, was studied for its taxonomic allocation. A comparison of the 16S rRNA gene sequence with those of the type strains of most closely related species of the family Enterobacteriaceae showed highest sequence similarities to the type strain of Kosakonia sacchari (99.5%), “Enterobacter oryzendophyticus” (98.8%), and Kosakonia radicincitans (98.6%).Construction of phylogenetic trees based on the 16S rRNA gene and partial sequences of four protein-coding genes, rpoB, gyrB, infB, and atpD (multilocus sequence analysis, MLSA) showed a distinct clustering of strain JM-387T with Kosakonia sacchari. DNA-DNA hybridizations between JM-387T and the type strains of most similar Kosakonia/“Enterobacter” species including K. sacchari LMG 26783T, “E. oryzendophyticus” LMG 26432T, K. radicincitans D5/23T, K. oryzae LMG 24251T, E. cancerogenus LMG 2693T, and E. cloacae subsp. dissolvens CCUG 25230T were in the range of 14.4–60.2%. The average nucleotide identity (ANI) of the genome sequence of the new strain to K. sacchari SP1T was 94.47%.Strain JM-387T had a typical enterobacterial fatty acid pattern consisting of the major fatty acids C16:0, C16:1 ω7c/C16:1 ω6c/C15:0 2OH, C18:1 ω7c/C18:1 ω6c with C14:0 3-OH as hydroxylated fatty acid.Genotypic data and the differentiating biochemical and chemotaxonomic properties showed that strain JM-387T represents a novel species of the genus Kosakonia, for which the name Kosakonia pseudosacchari sp. nov. (type strain JM-387T=CIP 110597T=DSM 27151T) is proposed.