The effects of ultra-high pressure (UHP) pretreatment (50–250 MPa) on the fish curing were studied. UHP increased the overall volatile compound concentration of cured fish. Among 50–250 MPa five treatment groups, 150 MPa UHP group exhibited the highest total free amino acid content (294.34 mg/100 g) with that of the control group being 92.39 mg/100 g. The activity of cathepsin L was increased under 50–200 MPa UHP treatment (62.28–58.15 U/L), compared with that in the control group (53.80 U/L). UHP treatment resulted in a significant increase in small molecule compounds, especially the amino acid dipeptides and ATP metabolic products. Under UHP treatments, the bacterial phyla Actinobacteriota (1.04–5.25 %), Bacteroidota (0.20–4.47 %), and Deinococcota (0.00–0.05 %) exhibited an increased abundance, and they promoted taste and flavor formation . Our results indicated that UHP is a promising pretreatment method to improve taste and flavour in cured fish by affecting the microorganisms, cathepsin, and proteins.
l -threonate is the metabolite of vitamin C, while d -erythronate is the metabolite of N -acetyl- d -glucosamine, the nutritional supplement for joint health. They are widely distributed in the environment and human biofluids. Nevertheless, the catabolisms of l -threonate and d -erythronate are sparsely reported. Here we explored the functional diversity of an acid sugar kinase family (Pfam families PF07005-PF17042), and discovered a novel 2-oxo-tetronate kinase. The conserved genome neighborhood of the 2-oxo-tetronate kinase encodes members of class-II fructose-bisphosphate aldolase family (F_bP_aldolase, PF01116) and a dehydrogenase family (PF03446-PF14833). Instructed by this analysis, we experimentally verified that these enzymes are capable of degrading l -threonate into dihydroxyacetone phosphate (DHAP) in Arthrobacter sp. ZBG10, Clostridium scindens ATCC 35704, and Pseudonocardia dioxanivorans ATCC 55486. Meanwhile, a convergent catabolic pathway for d -erythronate was characterized in P . dioxanivorans ATCC 55486. Moreover, the phylogenetic distribution analysis indicates that the biological range of the identified l -threonate and d -erythronate catabolic pathways appears to extend mostly to members of the Actinomycetota , Cyanobacteriota , Bacillota , Pseudomonadota , and Bacteroidota phyla.
危险品化学品经营许可证（带存储）