(Z)-Ethyl 2,4-diphenyl-3-(propyl­amino)­but-2-enoate

The title compound, C21H25NO2, adopts a Z conformation about the C=C double bond. The mol­ecular structure is stabilized by an intra­molecular N—H⋯O hydrogen bond and the dihedral angle between the aromatic ring planes is 76.04 (12)°. The atoms of the ethyl substituent are disordered over two sets of sites in a 0.60 (2):0.40 (2) ratio

Effect of Langmuir monolayer of bovine serum albumin protein on the morphology of calcium carbonate

Bovine serum albumin (BSA) Langmuir monolayer, as a model of biomineralization-associated proteins, was used to study its effect on regulated biomineralization of calcium carbonate. The effects of the BSA Langmuir monolayer and the concentration of the subphase solution on the nucleation and growth processes and morphology of the calcium carbonate crystal were investigated. The morphology and polymorphic phase of the resulting calcium carbonate crystals were characterized by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). Moreover, the interaction mechanisms of the subphase solution with the BSA Langmuir monolayer were discussed. It was found that BSA Langmuir monolayer could be used as a template to successfully manipulate the polymorphic phase and crystal morphology of calcium carbonate and had obvious influence on the oriented crystallization and growth. The final morphology or aggregation mode of the calcite crystal was closely dependent on the concentration of calcium bicarbonate solution. It is expected that this research would help to better understand the mechanism of biomineralization by revealing the interactions between protein matrices and crystallization of calcium carbonate crystal.Comment: 4 pages, 4 figure

Duck Eggs and Black-Yolked Salted Duck Eggs: Bacterial Diversity on Eggshells and Gene Function Prediction Using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt)

After comparing the bacterial load of black-yolked salted duck eggs (BSE) and that of duck eggs with different cleanliness degrees, it was found that the total bacterial count on the shell of severely stained eggs (DE) was distinctly higher than that on the shell of non-visually stained eggs (CE), and the total bacterial count in the shell membrane and contents of BSE increased greatly. Furthermore, 16S rDNA gene sequencing was used to analyze the differences in the composition and abundance of bacterial communities in CE, DE and BSE. It turned out that Proteobacteria, Firmicutes and Actinobacteria were the dominant phyla, accounting for 34.35%, 27.25% and 17.28% of the total abundance, respectively, while Bacteroidetes accounted for 8.29% of the total abundance. Proteobacteria was the dominant bacteria in DE and accounted for 89.01% of the total abundance, while the relative abundance of Firmicutes and Actinobacteria were 6.16% and 3.98%. The dominant phyla in BSE were Proteobacteria (76.50%), Bacteroidetes (8.00%), Actinobacteria (6.76%) and Firmicutes (5.43%). The abundance of Proteobacteria in DE and BSE was significantly increased. The dominant bacterial genera in CE were Nesterdella (9.08%), Campylobacter (7.91%), Streptococcus (3.41%) and Oligomonas (2.92%). In DE, Psychrobacter was the dominant genus, accounting for 86.01% of the total abundance, and the relative abundance of Acinetobacter was 2.20%. The dominant bacteria in BSE were Rolstonia (22.91%), Serratia (5.05%) and Actinomycetes (3.32%). The cluster analysis of bacterial diversity showed that the dominant microorganisms of BSE were close to those of DE. The microbial phenotype analysis showed that the dominant microorganisms of BSE were Gram-negative bacteria, had high oxidative stress tolerance and pathogenicity, and could tolerate oxidizing detergents. The results of microbial gene function prediction and species composition of metabolic pathways demonstrated that bacterial carbohydrate decomposition, lipid transport and metabolic oxidation in DE were stronger than those in CE. More coenzyme transport and metabolic pathways could make the biochemical reactions of bacteria from DE faster to produce more secondary metabolites, thus resulting in changes in the quality of duck eggs. This is consistent with the highest bacterial abundance in the secondary metabolite biosynthesis, transport and catabolism pathways in BSE. The results of this study provide theoretical support for the cleaner production of duck eggs