Effects of different curing concentrations and drying times on the microbial community structure and metabolites of dried Spanish mackerel.

Cured Spanish mackerel has a promising market owing to its nutritious nature as well as ease of transportation and preservation. However, the nutritional and flavor formation mechanism of Spanish mackerel after curing and drying is unclear. To overcome this problem, the effects of different processing conditions on the free amino acid, microbial community, and flavor of Spanish mackerel were explored. Staphylococcus and Cobetia are the main microorganisms in cured mackerel and are closely associated with the formation of their quality. Compared with fresh mackerel, cured mackerel contains increased levels of protein, fat, and chloride, contributing to its distinctive flavor. The contents of free amino acids in the BA64 group were substantially higher than those in other groups, particularly the contents of threonine, glycine, and tyrosine. These findings will contribute to the development of high-quality cured Spanish mackerel products and cured aquatic products.

Distinct changes of taste quality and metabolite profile in different tomato varieties revealed by LC-MS metabolomics.

Breeding of tomato varieties based on phenotypic traits can potentially lead to a decline in taste and nutritional values, thereby impacting consumer acceptance. However, taste is an intrinsic characteristic of tomatoes. Its decoding requires the identification of crucial compounds and the associated metabolic pathways implicated in taste development and formation. In this study, the taste parameter differences of four tomato varieties were distinguished using an electronic tongue. The content of organic acids and free amino acids, which were closely associated with taste variations, was quantitatively analyzed. Several important taste metabolites and metabolic pathways were identified based on LC-MS metabolomics and enrichment analysis. Through correlation analysis, it was determined that there existed significant associations between the taste, compounds, and metabolites of tomato varieties with different phenotypes. This study could provide references and theoretical basis for tomato breeding, as well as the control and evaluation of taste and quality of tomato varieties.

Transcriptional identification of differentially expressed genes associated with division of labor in Apis cerana cerana.

Workers of Apis cerana cerana undergo an in-hive nursing to outdoor foraging transition, but the genes underlying this age-related transition remain largely unknown. Here, we sequenced the head transcriptomes of its 7-day-old normal nurses, 18- and 22-day-old normal foragers, 7-day-old precocious foragers and 22-day-old over-aged nurses to unravel the genes associated with this transition. Mapping of the sequence reads to Apis mellifera genome showed that the three types of foragers had a greater percentage of reads from annotated exons and intergenic regions, whereas the two types of nurses had a greater percentage of reads from introns. Pair- and group-wise comparisons of the five transcriptomes revealed 59 uniquely expressed genes (18 in nurses and 41 in foragers) and 14 nurse- and 15 forager-upregulated genes. The uniquely expressed genes are usually low-abundance long noncoding RNAs, transcription factors, transcription coactivators, RNA-binding proteins, kinases or phosphatases that are involved in signaling and/or regulation, whereas the nurse- or forager-upregulated genes are often high-abundance downstream genes that directly perform the tasks of nurses or foragers. Taken together, these results suggest that the nurse-forager transition is coordinated by a social signal-triggered epigenetic shift from introns to exons/intergenic regions and the resulting transcriptional shift between the nurse- and forager-associated genes.

Particle size effect of curcumin nanosuspensions on cytotoxicity, cellular internalization, in vivo pharmacokinetics and biodistribution.

This study aimed to investigate the particle size effect on bioactivity, cellular internalization and bioavailability of curcumin (CUR) nanosuspension (CUR-NS). CUR-NSs of different particle sizes were prepared by two different anti-solvent precipitation methods. CUR-NS with the smallest size showed similar in vitro anticancer activity and bioavailability to the CUR solution, whereas nanosuspensions of larger particle sizes displayed higher in vitro cellular internalization and cytotoxicity, as well as higher in vivo AUC and slower clearance rate after i.v. administration in rats. CUR solution and different sized CUR-NSs reached the highest concentrations in the lung, followed by liver and spleen while the lowest concentration was observed in the brain after i.v. administration in mice. Specifically, CUR-NS of 70nm accumulated more in the brain, whereas CUR-NS of 200nm accrued more in liver and spleen. CUR-NS of 20nm displayed no significant biodistribution difference compared with CUR solution in all tissues.

Immunotoxicity of 1-methyl-3-octylimidazolium bromide on brocarded carp (Cyprinus carpio L.).

In the present study, the immunotoxicity of 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) on brocarded carp was evaluated by an acute exposure of 100-300mgL(-1) of [C(8)mim]Br for 7 days. The results showed 300mgL(-1) of [C(8)mim]Br exposure caused activity inhibition of specific and non-specific immune systems, mainly including IgM level, lysozyme activity, and complement C3 content, while 100mgL(-1) of [C(8)mim]Br activated fish immune system during the early periods of exposure (2-5 days). This result indicates that [C(8)mim]Br has immunotoxicity on brocarded carp. Additionally, histological observation revealed that 300mgL(-1) of [C(8)mim]Br-exposure led to remarkable damages to the hepatopancreas, kidney, and spleen of brocarded carp after 7 days of [C(8)mim]Br treatment, although not only change in kidney and spleen somatic indexes was found, but also no swelling or hemorrhage of carp viscera occurred.

[Study of the sensitizing effects of surfactants on the determination of aluminum by air-acetylene flame atomic absorption spectrometry].

The sensitizing effects of ten surfactants, such as cetyl trimethyl ammonium bromide (CTMAB) and cetyl pyridinium chloride (CPC), on the determination of aluminum were studied. The results showed that the cationic surfactants in the experiment were good sensitizers for the determination of aluminum, and the sensitization time was about 3.0. On the other hand, anionic surfactants had inhibition action, while particular surfactants had no action. With the sensitizing agent of CTMAB, the operating parameters of the spectrometer and the effects of CTMAB, solution medium and interfering elements in aluminum-nickel alloy sample were studied. The content of aluminum in aluminum-nickel alloy sample was determined by air-acetylene flame atomic absorption spectrometry, the linear range of aluminum of this method was 0.10-2.0 g x L(-1), the relative standard deviation was 2.6%, and the recoveries were in the range of 97%-103%.