L-asparaginase (E.C.3.5.1.1) hydrolyzes L-asparagine to L-aspartic acid and ammonia, which has been widely applied in the pharmaceutical and food industries. Microbes have advantages for L-asparaginase production, and there are several commercially available forms of L-asparaginase, all of which are derived from microbes. Generally, L-asparaginase has an optimum pH range of 5.0–9.0 and an optimum temperature of between 30 and 60 °C. However, the optimum temperature of L-asparaginase from hyperthermophilic archaea is considerable higher (between 85 and 100 °C). The native properties of the enzymes can be enhanced by using immobilization techniques. The stability and recyclability of immobilized enzymes makes them more suitable for food applications. This current work describes the classification, catalytic mechanism, production, purification, and immobilization of microbial L-asparaginase, focusing on its application as an effective reducer of acrylamide in fried potato products, bakery products, and coffee. This highlights the prospects of cost-effective L-asparaginase, thermostable L-asparaginase, and immobilized L-asparaginase as good candidates for food application in the future.

Carbon nanodots (CNDs) have attracted substantial scientific curiosity because of their intriguing stimuli-responsive optical properties. However, one obstacle to the more widespread use of CNDs as transducers for e.g., biodetection...

In the treatment of methyl orange simulation printing and dyeing wastewater by catalytic wet air oxidation method, the Ru series catalysts were prepared with the equal amount impregnation method. The catalyst activity and stability were characterized by the decolorization rate of the water samples, and the eluted metal ion concentration from the catalyst of the water samples. XRD, SEM, FT-IR were used to characterize the catalysts. The results showed that: when active allocation ratio of the catalyst was Ru:Cu:Fe:Ce:La = 1:0.5:0.5:0.5:0.5, the degradation rate of methyl orange could reach up to 98.5%. And the concentration of each metal component eluted lower after the reaction, while its activity and stability were relatively high.The active component of 1wt% Ru catalyst mainly existed as the form of γ-Al2O3, RuO2, La2O3, La2CuO4 and CeO2. The surface of catalyst was relatively flat and flaky. The Ru catalyst appeared strong infrared absorption in the vicinity of 1070 cm-1, 1650 cm-1 and 3450 cm-1.

Black liquor was processed with wet air oxidation technology in these experiments. Influence of its influent concentration was researched. COD, absorbance, turbidity and pH of the water samples were measured and analyzed. The results showed that: the treatment effect of each index in black liquor treatment with wet air oxidation method gradually weakened with the increase of influent concentration from the overall point of view; when papermaking black liquor was processed by wet oxidation, the water samples was weak alkaline basically, with pH in between 7.83 to 8.70. COD removal, decolorization removal and turbidity removal basically improved with the extension of time, the COD removal and decolorization removal can reach 50 % or more basically. When influent concentration was greater than 5500 mg/L, turbidity removal was less than 40 %. So the influent concentration of the black liquor in wet oxidation treatment should not be too large, the influent concentration of 2500 mg/L to 4000 mg/L is appropriate.