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With the industrialization of the food industry and the advancement of production technology, along with the simultaneous modern fast-paced lifestyle and the growth of the central kitchen market, pre-made dishes have become an important choice for both the catering industry and households. Pre-made dishes made primarily with pork as the main ingredient have become an important component of the pre-made dishes market and the market share continues to grow steadily. The quality of pre-made pork dishes is closely linked to processing technology, storage techniques and quality control measures. This paper reviews the material characteristics, processing and quality control technologies of pre-made pork dishes and aims to guide for their high-quality development.

In order to investigate changes in flavor substances of lightly-pickled cucumbers during storage, volatile compounds were analyzed by electronic nose and gas chromatography-ion mobility spectrometry (GC-IMS). The results showed that flavor characteristics of lightly-pickled cucumbers changed obviously during storage. A total of 56 volatile organic compounds (VOCs) were detected by GC-IMS, including 10 alcohols, 30 aldehydes, 8 ketones, 5 esters, 1 furan, 1 acid, and 1 alkane. With the extension of storage period, the relative contents of aldehydes, alcohols and ketones decreased significantly, while the contents of esters increased significantly (P1), including cis-6-nonenal, nonenal, 1-penten-3-one, isobutyraldehyde, trans-2,cis-6-nonadienal, and trans-2-octenal. Among them, trans-2-octenal increased with the relative extension of storage time, which might be the main off-flavor compound for flavor deterioration. This study can provide a theoretical basis for flavor quality evaluation of lightly-pickled cucumbers during storage.

Premade meat and poultry dishes refer to the finished or semi-finished products that use meat and poultry materials as the main ingredients, which undergo pretreatments and stored, transported and sold under room temperature or cold chain conditions. Flavor is an important factor that determines consumers' willing for premade dish purchase. However, due to raw material characteristics, microbial metabolism, nutrients oxidation or degradation, inappropriate reheating, the premade meat and poultry dishes might generate some unpleasant off-flavors. The off-flavors might have strong negative impact on the sensory quality of premade dishes, which restricts the further development of the whole industry. The commonly seen off-flavor substances in premade meat and poultry dishes include hexanal with sour note, nonanal, octanal, decanal and (E,E)-2,4-decadienal with waxy and oily note, (E)-2-decenal with greasy fatty note, 3-methylbutyraldehyde and 2-methylbutyraldehyde with musty note, butyric acid with a strong cheesy note, 3-methylbutyric acid with sweaty note, dimethyl trisulfide, dimethyl sulphide with sulphurous note, and 1-octen-3-ol with earthy note etc. This paper reviews the main sources of premade meat and poultry dishes off-flavors, summarizes the off-flavors inhibiting and masking techniques applied in premade dish preparation. This study would provide practical guidance and reference for the innovation and development of the flavor quality control in premade dish industry.

Objective To explore the composition of culturable bacteria in platelets through bacterial culturomics and verify the results of culturomics and metagenomics to improve the detection rate of bacteria in platelets. Methods Platelet samples from 6 healthy people were collected. Eight kinds of culture media were placed in aerobic conditions and 12 kinds of culture media were placed in anaerobic conditions for large-scale culture and isolation of bacteria in platelets. The isolated single colony was identified by 16S rRNA gene sequencing. The bacterial abundance of healthy human platelet microbiome was analyzed by metagenomic sequencing, and the cultivable bacterial species in platelets was confirmed based on metagenomic and culturomics results. Results A total of 90 strains of bacteria belonging to 3 phylums, 5 classes, 5 orders, 7 families, 9 genus and 23 species were isolated from 6 platelet samples by culturomics. Among them, the strains with more monoclonal clones at the species level were Brevundimonas aurantiaca (16.7%), Bacillus sp. Y1 (15.6%), Cutibacterium acnes (14.4%) and Brevibacillus brevis (13.3%). The platelet samples sequenced by mNGS showed that the abundance values of Proteobacteria, Firmicutes and Actinobacteria were high. The bacteria detected by both culturomics and metagenomic sequencing methods were as follows: Firmicutes: Bacillus sp. Y1, B. thuringiensis, B. cereus, B. mobilis, B. velezensis, Staphylococcus epidermidis, and Brevibacillus brevis; Actinobacteria: Cutibacterium acnes; Proteobacteria: Escherichia coli and Delftia tsuruhatensis. Conclusion The mutual validation of culturomics and metagenomics has identified some bacteria, proving that bacteria exist in platelets.

Objective To explore the influence of common methods of reducing non-viral nucleic acid on the abundance of plasma virus group. Methods Three kinds of library construction, five kinds of centrifugation conditions, two kinds of filters, four kinds of enzymes and four concentrations of chloroform were used to treat plasma samples added quantitatively 2.16 mL of pseudorabies virus(PRV) and 2.16 mL of porcine parvovirus(PPV). A total of 21.6 mL of plasma samples were processed, including 54 samples. Subsequently, nucleic acid was extracted, mitochondrial DNA(mtDNA) and two viruses were quantitated, the library of the next generation sequencing was constructed, Illumina NovaSeq 6000 was used for the next generation sequencing. The sequencing data were compared with Kraken Py 2.0 software, and the species annotation analysis was conducted. The corresponding species classification information of each segment was obtained to analyze the impact of different reducing non-viral nucleic acid methods on the relative abundance of microorganisms and two indicator viruses. Results After sequencing by Illumina NovaSeq 6000, 306.27 GB raw data and 193.17 GB clean data were obtained, with Q20>90%, Q30>85%, Error Rate of 0.03%, and average GC Content of 45.02%. The DNA library construction process significantly increased the proportion of microbial sequences and the PRV abundance [(91.8±0.5)%](P

BackgroundLead exposure induces microglial cell death, of which the mechanism is unclear. Ferroptosis is a new death form and its role in microglia death has not been reported. ObjectiveTo investigate the role of ferroptosis in microglia following lead exposure in order to provide a theoretical basis for the mechanism of lead neurotoxicity. MethodsMicroglial cell line BV-2 cells were co-cultured with 0, 10, 20 and 40 μmol·L−1 lead acetate for 24 h. The 40 μmol·L−1 lead acetate group with iron chelator (DFO) was named the 40+DFO group. Changes in BV-2 cell morphology after lead exposure were observed under an inverted microscope; tissue iron kit and glutathione kit were used to detect intracellular iron and glutathione (GSH) respectively; flow cytometry was applied to detect lipid reactive oxygen species (lipid ROS) immunofluorescence intensity. Western blotting and qPCR were adopted to detect the expressions of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), transferrin receptor 1 (TFR-1), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1) protein and mRNA. ResultsCompared with the control group, the number of BV-2 cells decreased with increasing doses of lead and the cells showed a large, round amoeboid shape. The intracellular levels of iron of BV-2 cells were (1.08±0.04), (1.29±0.03), and (1.72±0.10) mg·g−1 (calculated by protein, thereafter) in the 10, 20, and 40 μmol·L−1 lead acetate groups, respectively, significantly higher than that in the control group (P

In order to enhance the photodynamic inactivation (PDI) effect of curcumin, a novel class of halogenated curcumin derivatives X-cur (X = F, Cl or Br) was synthesized and screened for its potential for PDI by ultraviolet-visible (UV-Vis) absorption and fluorescence spectroscopy, singlet oxygen (1O2) generation capacity and theoretical calculations of excited states. The results demonstrated that as the relative molecular mass of the nonmetallic heavy atom halogen increased, the spin-spin coupling effect was gradually strengthened, so the smallest energy level difference (ΔEst(S1-T3)) between singlet excited state (S1) and triplet excited state (T3) (0.140 eV) and the highest spin-orbit coupling value (0.642 262 cm-1) were observed in Br-cur. This finding suggested that Br-cur was most likely to undergo transition into triplet state through intersystem crossing. Furthermore, compared to curcumin and other halogenated curcumins, Br-cur exhibited the smallest energy level difference (3.260 eV) between its S1 and ground state (S0) . Due to the aforementioned factors, Br-cur was highly prone to photooxidation and had the highest 1O2 generation capacity. Br-cur had a PDI effect on Vibrio parahaemolyticus, a prevalent foodborne pathogen in aquatic products, which depended on its concentration and light exposure duration and was significantly higher than that of curcumin. Thus, Br-cur has great potential for application as a novel PDI agent.

The aim of this study was to investigate the antioxidant and anti-aging effects and underlying mechanisms of inactivated Bacillus sp. DU-106 in Caenorhabditis elegans. The antioxidant activity of inactivated Bacillus sp. DU-106 was evaluated by in vitro free radical scavenging assay. The effects of inactivated Bacillus sp. DU-106 at various concentrations on the lifespan, stress response and antioxidant capacity of C. elegans were observed. The results illustrated that inactivated Bacillus sp. DU-106 possessed strong free radical scavenging capacity in vitro, meanwhile, inactivated Bacillus sp. DU-106 effectively extended the lifespan of C. elegans and improved its movement and stress resistance. Different concentrations of inactivated Bacillus sp. DU-106 increased the levels of catalase (CAT), superoxide dismutase (SOD) and glutathione in a dose-dependent manner. Fluorescence microscopy showed that treatment with inactivated Bacillus sp. DU-106 significantly reduced lipofuscin levels in C. elegans. In conclusion, inactivated Bacillus sp. DU-106 can exert an anti-aging effect perhaps by reducing lipofuscin accumulation and increasing the levels of antioxidant enzymes in C. elegans. This study provides a powerful basis for the development of Bacillus for application in nutraceuticals.