Enzymatic synthesis of triolein (TAG) has become an important approach for green development in the fine chemical industry due to its high product purity, low pollution, and simple downstream separation. However, the industrial application of enzymatic TAG synthesis is limited by insufficient thermal stability and low catalytic efficiency of lipases at high temperatures. Therefore, developing lipases with excellent thermostability and high catalytic activity is the key to technological breakthroughs. In this study, recombinant rice bran thermostable lipase (RBL-LC6) derived from rice bran was used as the catalyst to investigate the optimal conditions for the enzymatic esterification of oleic acid and glycerol for TAG production at high temperatures. The effect of temperature on product distribution was first explored. Then single-factor experiments were carried out to examine the effects of reaction time, temperature, water mass fraction, enzyme mass fraction, and substrate molar ratio on TAG synthesis. The enzymatic reaction kinetics was also analyzed. The results showed that as the temperature increased from 40 ℃ to 90 ℃, RBL-LC6 exhibited better catalytic performance for TAG synthesis at 80 ℃, with a TAG yield of 48.04%. After optimization, the highest TAG yield reached 55.13% under the optimal conditions: reaction time 6 h, temperature 80 ℃, water mass fraction 1.0%, enzyme mass fraction 0.2%, and substrate glycerol/oleic acid molar ratio 1∶3.5. Kinetic analysis indicated that the esterification catalyzed by RBL-LC6 followed the Ping-Pong Bi-Bi mechanism and the enzyme exbibited a stronger affinity for glycerol than for oleic acid. This study aimed to provide theoretical and technical support for the green enzymatic synthesis of TAG under high-temperature conditions.

To investigate the protective mechanism of yeast hydrolysate (YH) on human umbilical vein endothelial cell injury induced by H₂O₂, antioxidant activity of YH was studied. The results show that the median effective concentration (EC₅₀) of YH on DPPH scavenging is 1.85 mg/mL, showing good antioxidant activity. And YH of high-dose (500 μg/mL) can significantly alleviate the cell proliferation inhibition induced by H₂O₂, reduce malondialdehyde (MDA) production and increase the level of superoxide dismutase (SOD), thereby resisting cell oxidative damage of HUVEC caused by H₂O₂. Moreover, transcriptomics sequencing reveals that YH can significantly up-regulate the expression of genes SOD2 and HMOX1. The research results not only provide basic data for YH to reduce endothelial cell oxidative damage, but also provide a theoretical basis for the application of YH in the fields of antioxidation functional foods and medicine.

Food safety is a major global public health concern. Targeted proteomics based on mass spectrometry (MS) plays an increasingly important role in addressing this issue due to its high sensitivity, specificity, and quantitative accuracy. In this article, two common targeted proteomics approaches including multiple reaction monitoring (MRM) and parallel reaction monitoring (PRM) are briefly introduced. The progress that has been made in the application of targeted proteomics in food safety detection in the last five years is summarized including authentication of animal-derived foods, analysis of food allergens, and detection of foodborne pathogens and their toxins. Meanwhile, an outlook on the future development of this field is given.

As the key component of quantitative real-time polymerase chain reaction (qPCR) technology, Taq DNA polymerase’s performance directly affects the further development of qPCR technology. However, the wild-type Taq DNA polymerase has inadequate properties in inhibitor tolerance and elongation performance. To obtain Taq DNA polymerase with high performance, this study fused the double-stranded DNA-binding protein Sso7d or Sto7d to the N-terminal or C-terminal of wild-type Taq DNA polymerase by genetic engineering technology, which four soluble expression transformants were constructed, and then the better transformant was screened by tolerance test. The results show that the better transformant Taq-Sto has the highest tolerance, with no impact on its thermal stability, and the target can be successfully amplified by Taq-Sto under the extension condition of 1 s/kbp, indicating that Taq-Sto has enhanced extension performance. It also shows good tolerance to humic acid, tannic acid and whole blood in TaqMan qPCR system. EMSA experiment shows that the binding affinity of Taq-Sto to DNA template is improved, which is beneficial to enhancing the competitiveness of Taq-Sto to DNA template. Taq-Sto was applied to the TaqMan qPCR detection of African swine fever virus (ASFV). Compared with commercial reagents,Taq-Sto has lower detection limit of ASFV, and the detection sensitivity in 2%～6% (volume fraction) pig fecal samples or pork samples is 100.0% and 85.4%, respectively, indicating that Taq-Sto has more advantages in the field of direct qPCR detection. The results provide a reference for the development of DNA polymerase with better performance, which is conducive to further promoting the practical application of qPCR technology.