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Potential furfural compounds were detected by reverse phase high performance liquid chromatography (HPLC)-diode array detector (DAD) in milk-based formula (MBF), ultra-high temperature milk (UHT) and pasteurised yoghurt (PY). The content of potential 5-hydroxylmethyl-2-furaldehyde (HMF) and 2-furaldehyde (F) are significantly different in MBF, UHT and PY. 2-Furyl methyl ketone (FMC) and 5-methyl-2-furaldehyde (MF) were not detected in MBF, UHT and PY. Stress testing selected high temperature and high humidity to study the evolution of furfural compounds in MBF, UHT and PY. The contents of potential HMF and F sharply increased under high temperature conditions, while they showed little change under high humidity conditions. Accelerated testing and long-term testing were also conducted. Finally, regression equations of temperature–time-furfural content relationships were derived, by which the contents of furfural compounds in these dairy products stored under certain conditions for a certain time could be predicted. [ABSTRACT FROM AUTHOR]

Myeloid differentiation factor 88 (MyD88) is a crucial adaptor protein for Toll-like receptor (TLR)-mediated signaling pathways and plays an important role in immune response. In this study, the full-length cDNA of MyD88 from Macrobrachium rosenbergii (MRMyD88) was cloned. The MRMyD88 cDNA is 1758 bp long and contains a 1398-bp open reading frame. Multiple sequence alignment and phylogenetic analysis revealed that the amino acid sequence of MRMyD88 shared high identity with the known MyD88 proteins. The MRMyD88 mRNA was widely expressed in all examined tissues, with highest level in intestine, followed by gonad and pleopod. Furthermore, the MRMyD88 promoter region, spanning 1622 bp, contains several transcription factor-binding sites, including nine GATA-1 box motifs. Electrophoretic mobility shift assay showed that Gfi-1, SRF, and Oct-1 bind to the upstream region of MRMyD88. Additionally, the results showed that the expression levels of TLR1 , TLR2 and TLR3 were different in response to Vibrio anguillarum , Lactobacillus plantarum and Aeromonas hydrophila infections. However, these bacteria significantly increased the expression levels of MyD88 and prophenoloxidase. These data suggest that the TLR -mediated signaling pathway is MyD88 -dependent in response to pathogenic and probiotic bacteria in M. rosenbergii. [ABSTRACT FROM AUTHOR]

Vibrio anguillarum is a globally distributed aquatic pathogen, and its flagellin B (FlaB) protein can evoke innate immune responses in hosts. In order to explore the role of FlaB in V. anguillarum infection, we constructed a FlaB-deficient mutant using overlapping PCR and two-step homologous recombination, and gene sequencing confirmed successful knockout of the FlaB gene. Scanning electron microscopy showed no significant differences in the morphological structure of the flagellum between wild-type and FlaB-deficient strains. The mutant was subsequently injected into the freshwater prawn (Macrobrachium rosenbergii) to explore its pathogenicity in the host, and expression of myeloid differentiation factor 88, prophenoloxidase, catalase, superoxide dismutase and glutathione peroxidase was investigated by real-time PCR. The results showed that deletion of FlaB had little effect on V. anguillarum -induced expression of these immune-related genes (p > 0.05). In general, the FlaB mutant displayed similar flagella morphology and immune characteristics to the wild-type strain, hence we speculated that knockout of FlaB might promote the expression and function of other flagellin proteins. Furthermore, this study provides a rapid and simple method for obtaining stable mutants of V. anguillarum free from foreign plasmid DNA. [ABSTRACT FROM AUTHOR]

• Tautomer distribution of GlcNAc in D 2 O or DMSO‑ d 6 was investigated by NMR techniques. • The tautomer distribution of GlcNAc in common solvents for biorefinery was studied. • Zn2+and Sn4+ promoted the conversion of α-pyranose to β-pyranose. • Amino acid ionic liquids increase the proportion of β-pyranose in DMSO‑ d 6. The tautomer structure of monosaccharides plays an important role in its conversion and utilization, which is mainly manifested in the selectivity of the product and the reaction mechanism. The tautomer distributions of N -acetyl- D -glucosamine (GlcNAc), a natural nitrogen-containing monosaccharide were investigated by quantitative 1H NMR (1H qNMR) and 13C NMR (13C qNMR) at 298 K under the condition commonly utilized for biorefinery. Catalysts used for biorefinery, i.e. BaCl 2 , KCl, ZnCl 2 , MgCl 2 , B(OH) 3 , SnCl 4 ·5H 2 O and amino acid ionic liquid were introduced into D 2 O or DMSO‑ d 6 to explore the tautomer distributions of GlcNAc. The introduction of ZnCl 2 and SnCl 4 ·5H 2 O promoted the conversion of α-pyranose to β-pyranose. The introduction of amino acid ionic liquid has little effect on the percentage of tautomers in D 2 O. However, when the amino acid ionic liquid, such as [Thr]Cl, was introduced into DMSO‑ d 6 , the proportion of β-pyranose increased to 29.06%, compared with no catalyst introduced. Besides, we also studied the tautomer distributions of GlcNAc in commonly utilized reaction solvents for biorefinery, such as N,N -dimethylformamide, N , N -dimethylacetamide, N -methyl-2-pyrrolidinone, ethylene and glycerol. In these solvents, the proportion of β-pyranose in N,N -dimethylformamide and glycerol was reduced to 25.84% and 38.38%, respectively. This study provides the basic experimental data of tautomer distributions of GlcNAc, and guided the conversion and utilization of GlcNAc in the future. Graphical abstract [Display omitted]. [ABSTRACT FROM AUTHOR]