Study On The Antioxidant Activity Of Anthocyanin In Mulberry And Its Interaction With Bovine Hemoglobin

In this paper,a new method of microemulsion extraction-response interface was proposed,which was combined with ultrasonic-assisted solvent method,it was applied to purify anthocyanins in mulberry for the first time.The antioxidant activity and three systems of thermal degradation kinetics for anthocyanins in mulberry were systematically studied,the anthocyanins mixed with drug and encapsulated to improve the stability.The interaction between anthocyanins and bovine hemoglobin at different concentrations and changes in system viscosity and conductivity in different pH were explored.The research content of this paper mainly includes:1.Exploration of the extraction process of anthocyanins from mulberry and its composition analysisCombining colloid with interface chemistry and separation engineering,the anthocyanins in mulberry were extracted by ultrasonic-assisted solution soaking method,response surface method,microemulsion extraction method and column chromatography method.So the optimal solvent component extraction conditions were:ethanol concentration was 85.87%;solid-liquid ratio was 1:6.3;ratio of ethanol to acetic acid was 3.9:1;the optimal external extraction conditions were:water bath was at 75 ? for 19 minutes;ultrasonic power was 125.4 W;ultrasonic time was 29.6 min;equilibrium time was 60.6 min.And the optimum conditions by AB-8 were:temperature was 40?;60%ethanol eluant;pH value was 6.According to the optimum processing conditions,anthocyanins accounted for 87.62%respectively in anthocyanin sample.The purification effects of mulberry anthocyanins were analyzed by UV-visible spectroscopy,infrared spectroscopy and high-performance liquid chromatography.Under the optimal conditions,three mulberry sample sources were analyzed and the quality of Jiangsu producing area was better.2.Antioxidant activity of anthocyanins in mulberryThis chapter explored the antioxidant activity of mulberry anthocyanins,vitamin C and cyanidin standard solution were used as controls to evaluate the antioxidant capacity of mulberry anthocyanins,and with total anthocyanins reducing power,DPPH radical scavenging capacity to hydroxyl radical scavenging ability,and ability to inhibit lipid peroxidation as indicators.The thermodynamic stability of the crude extract optimized by response surface method and column separation method were also investigated.In addition,anthocyanins and ribavirin were used as core materials,and encapsulated with chitosan to improve their stability,the radius of the nanospheres were between 80 nm and 110 nm,ribavirin and anthocyanins could be almost encapsulated in the nanospheres,and with 89.32%and 85.08%high-encapsulation efficiency.3.Interaction between anthocyanins and bovine hemoglobinThe interaction between anthocyanins and bovine hemoglobin,variety law in system viscosity and conductivity were systematically studied by UV-visible,fluorescence,CD,viscosity,conductivity and negative staining under different pH conditions.At the same time,the synergistic effect of ribavirin and anthocyanin on bovine hemoglobin was explored.With the increase of anthocyanin of anthocyanins,peptide chain of compound hemoglobin was increased,and the tryptophan and tyrosine residues were gradually exposed.Moreover,the energy transfer efficiency of anthocyanin interaction with bovine hemoglobin was 0.2065,the critical distance R0 was 1.973 nm,and the bonding distance was 2.465 nm.