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In order to optimize the enzymatic-assisted ultrasonic extraction method of total flavonoids from Sedum aizoon L., the effects of solid-liquid ratio, ethanol concentration, extraction temperature, extraction time, and ultrasound power on the extraction rate were investigated by single factor experiment. The optimum technological conditions for enzymatic-assisted ultrasonic extraction of total flavonoids from Sedum aizoon L. were as follows: solid-liquid ratio 1:55 (g/mL), ethanol volume fraction 60%, extraction temperature 45°C, extraction time 2 5 min, and ultrasound power 150 W. Under these conditions, the extraction rate of total flavonoids from Sedum aizoon L. could reach 10.77%. The antioxidant activity of flavonoids from Sedum aizoon L. was positively correlated with the concentration, and the greater the concentration, the stronger the antioxidant capacity. At a concentration of 0.96 mg/mL, the scavenging rate of the DPPH• radical reached 67.5%. The scavenging rate of the ABTs+• radical reached 55.8% at a concentration of 1.92 mg/mL.

Four excellent lactic acid bacteria were screened from Kefir. After morphological observation, physical and chemical detection, and 16SrDNA sequence comparison, three strains were preliminarily identified as Lactobacillus Kefir, and one strain was Lactobacillus acidophilus. Two strains were selected to study their biological characteristics. The results showed that the lactic acid bacteria isolated from Kefir had good probiotic properties, with a survival rate of more than 42% after artificial gastric juice digestion for 3 hours and more than 46% after artificial intestinal juice digestion for 6 hours; It has inhibitory effects on intestinal pathogenic bacteria such as Staphylococcus aureus and Escherichia coli; Does not produce hemolysis; There are different levels of resistance to antibiotics.

In this study, carrageenase immobilization was evaluated with a concise and efficient strategy. Pomelo peel cellulose (PPC) modified by polyethyleneimine (PEI) using the physical absorption method was used as a carrier to immobilize carrageenase and achieved repeated batch catalysis. In addition, various immobilization and reaction parameters were scrutinized to enhance the immobilization efficiency. Under the optimized conditions, the enzyme activity recovery rate was more than 50% and 4.1 times higher than immobilization with non-modified pomelo peels. The optimum temperature and pH of carrageenase after immobilization by PEI-modified pomelo peel, at 60°C and 7.5 respectively, were in line with the free enzyme. The temperature resistance was reduced, inconsistent with free enzyme, and pH resistance was increased. A significant loss of activity (46.8%) was observed after reusing it thrice under optimal reaction conditions. In terms of stability, the immobilized enzyme conserved 76.0% of the initial enzyme activity after 98 days of storage. Furthermore, a modest decrease in the kinetic constant ( K m ) value was observed, indicating the improved substrate affinity of the immobilized enzyme. Therefore, modified pomelo peel is a verified and promising enzyme immobilization system for the synthesis of inorganic solvents.

Prostate cancer is a slow-growing cancer whose incidence increases with age. IL-6 expression is significantly increased in a variety of malignant tumor stroma, which is a key factor involved in the association between inflammation and tumor. So as to investigate how prostate cancer works, recombinant IL-6 was used to stimulate human prostate cancer cells (PC-3). After treatment for 24,48,72h, the viability of cancer cells was detected by CCK-8 experiment. The effect of recombinant IL-6 on the invasion of prostate cancer cells was analyzed by Transwell experiment. The results showed that IL-6 can increase the viability of prostate cancer cells and facilitate the invasion of prostate cancer cells.