Detailed Dimethylacetal and Fatty Acid Composition of Rumen Content from Lambs Fed Lucerne or Concentrate Supplemented with Soybean Oil

Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18∶1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18∶2n−6 and 18∶3n−3. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18∶0 might be produced during biohydrogenation of the 18∶3n−3.     

AuPd–MnOx/MOF–Graphene: An Efficient Catalyst for Hydrogen Production from Formic Acid at Room Temperature

The safe and efficient storage and release of hydrogen are widely recognized as the main challenges for the establishment of a fuel‐cell‐based hydrogen economy. Formic acid (FA) has great potential as a safe and convenient source of hydrogen for fuel cells. Despite tremendous efforts, the development of heterogeneous catalysts with high activity and relatively low cost remains a major challenge. The synthesis of AuPd–MnO_x nanocomposite immobilized on ZIF‐8–reduced‐graphene‐oxide (ZIF‐8–rGO) bi‐support by a wet‐chemical method is reported here. Interestingly, the resultant AuPd–MnO_x/ZIF‐8–rGO shows excellent catalytic activity for the generation of hydrogen from FA, and the initial turnover frequency (TOF) reaches a highest value of 382.1 mol H₂ mol catalyst^?1 h^?1 without any additive at 298 K. This good performance of AuPd–MnO_x/ZIF‐8–rGO results from the modified electronic structure of Pd in the AuPd–MnO_x/ZIF‐8–rGO composite, the small size and high dispersion of the AuPd–MnO_x nanocomposite, and also the strong metal‐support interaction between the AuPd–MnO_x and ZIF‐8–rGO bi‐support.     

Identification of the Simian Virus 40 Which Replicates When Simian Virus 40-Transformed Human Cells Are Fused with Simian Virus 40-Transformed Mouse Cells or Superinfected with Simian Virus 40 Deoxyribonucleic Acid

Simian virus 40 (SV40) was rescued from heterokaryons of transformed mouse and transformed human cells. To determine whether the rescued SV40 was progeny of the SV40 genome resident in the transformed mouse cells, the transformed human cells, or both, rescue experiments were performed with mouse lines transformed by plaque morphology mutants of SV40. The transformed mouse lines that were used yielded fuzzy, small-clear, or large-clear plaques after fusion with CV-1 (African green monkey kidney) cells. The transformed human lines that were used did not release SV40 spontaneously or after fusion with CV-1 cells. From each mouse-human fusion mixture, only the SV40 resident in the transformed mouse cells was recovered. Fusion mixtures of CV-1 and transformed mouse cells yielded much more SV40 than those from transformed human and transformed mouse cells. The rate of SV40 formation was also greater from monkey-mouse than from human-mouse heterokaryons. Deoxyribonucleic acid (DNA) from SV40 strains which form fuzzy, largeclear, or small-clear plaques on CV-1 cells was also used to infect monkey (CV-1 and Vero), normal human, and transformed human cell lines. The rate of virion formation and the final SV40 yields were much higher from monkey than from normal or transformed human cells. Only virus with the plaque type of the infecting DNA was found in extracts from the infected cells. Two uncloned sublines of transformed human cells [W18 Va2(P363) and WI38 Va13A] released SV40 spontaneously. Virus yields were not appreciably enhanced by fusion with CV-1 cells. However, clonal lines of W18 Va2(P363) did not release SV40 spontaneously or after fusion with CV-1 cells. In contrast, several clonal lines of WI38 Va13A cells did continue to shed SV40 spontaneously.     

Effect of Diets Supplemented with Different Levels of Manganese,Zinc, and Copper from their Organic or Inorganic Sources on Egg Production and Quality Characteristics in Laying Hens

This experiment was conducted to evaluate the effect of zinc, manganese, and copper sources (inorganic vs. organic) in the diet on laying performance and eggshell quality characteristics. One hundred and eighty Hy-Line W-36 layers at 38 weeks of age were allocated to 36-layer cages of five hens each. Each six cages were randomly assigned to one of the six experimental diets fed from 38 to 53 week of age. In three experimental treatments, the basal diet was supplemented with 65–75–7 or 65–75–7 or 40–40–7 mg/kg of Zn, Mn, and Cu, respectively, from their oxide or sulfate sources. Three other groups were fed diets supplemented with 20–20–3.5 or 40–40–7.5 or 60–60–10.5 mg/kg of organic forms of Zn, Mn, and Cu, respectively. Dietary treatments significantly did affect feed intake (P < 0.001), feed conversion ratio (P < 0.001) and percentage of broken eggs (P < 0.05). Substitution of Zn and Mn oxides (65 and 75 mg kg⁻¹, respectively) with equal amounts of their sulfate forms significantly improved feed intake, feed conversion ratio, percentage of broken eggs, and Haugh Unit (P < 0.05). In addition, laying hens maintained their performance when substitution of Zn and Mn oxides and Cu sulfate (65, 75, and 7 mg kg⁻¹, respectively) reduced up to 20, 20, and 3.5 mg kg⁻¹ by amino acid complexes of the microelements. The results showed that a corn–soybean diet supplemented with the organic forms of Zn, Mn, and Cu at a dosage 50% to 75% lower than NRC recommendation is sufficient to maintain laying performance and can improve eggshell and albumen qualities of the egg in laying hens.     

Formation of the N,N′-Dialkylpyrazine Cation Radical from Glyoxal Dialkylimine Produced on Reaction of a Sugar with an Amine or Amino Acid

The formation of an intermediate product, which could easily give a radical product, in an early stage of the Maillard reaction was confirmed commonly occur in various sugar-amino compound systems, by detection of the N,N′-dialkylpyrazine cation radical generated on the addition of ascorbic acid (AsA) to the reaction mixtures. This intermediate was produced immediately after to glycosylamine formation, prior to Amadori rearrangement, and completely parallel to the formation of glyoxal dialkylimine, which was identified by TLC as a main component of the extract. Authentic glyoxal dialkylimine was shown to produce an identical radical on treatment with both reducing agents and acids instead of AsA. It was thus demonstrated that the intermediate is glyoxaldialkylimine and that acid hydrolysis followed by reduction is required for production of the free radical.     

Hydrogen Peroxide from the Oxidative Burst Is Neither Necessary Nor Sufficient for Hypersensitive Cell Death Induction, Phenylalanine Ammonia Lyase Stimulation, Salicylic Acid Accumulation, or Scopoletin Consumption in Cultured Tobacco Cells Treated with Elicitin

H(2)O(2) from the oxidative burst, cell death, and defense responses such as the production of phenylalanine ammonia lyase (PAL), salicylic acid (SA), and scopoletin were analyzed in cultured tobacco (Nicotiana tabacum) cells treated with three proteinaceous elicitors: two elicitins (alpha-megaspermin and beta-megaspermin) and one glycoprotein. These three proteins have been isolated from Phytophthora megasperma H20 and have been previously shown to be equally efficient in inducing a hypersensitive response (HR) upon infiltration into tobacco leaves. However, in cultured tobacco cells these elicitors exhibited strikingly different biological activities. beta-Megaspermin was the only elicitor that caused cell death and induced a strong, biphasic H(2)O(2) burst. Both elicitins stimulated PAL activity similarly and strongly, while the glycoprotein caused only a slight increase. Only elicitins induced SA accumulation and scopoletin consumption, and beta-megaspermin was more efficient. To assess the role of H(2)O(2) in HR cell death and defense response expression in elicitin-treated cells, a gain and loss of function strategy was used. Our results indicated that H(2)O(2) was neither necessary nor sufficient for HR cell death, PAL activation, or SA accumulation, and that extracellular H(2)O(2) was not a direct cause of intracellular scopoletin consumption.