Analysis of the sensitization activity of leaves protein.

The determination of allergenic proteins in leaves, which is the main components of immune activity, has enabled the development of a more effective method for evaluating the activity of extracted leaves protein. In this study, the extraction process of leaves protein was optimized based on a single factor experiment. The hemagglutination-related properties of leaves protein, such as (thermal, acid-base) stability, sugar binding specificity, ion binding characteristics, and hemolytic activity, were detected. The optimal combination of extraction process was: extraction time of 6 h, material-liquid ratio of 1:8, and ammonium sulfate saturation of 60%. The extraction rate of moringa leaf protein under this condition was 14.37 mg/g. The molecular weight of moringa leaf protein was analyzed by SDS-PAGE, and the molecular weight was mainly concentrated around 23 kDa~70 kDa, with the highest content of 35 kDa (major allergen). The study of the hemagglutination characteristics of leaves protein revealed that the protein exhibited high stability at temperatures below 60°C, with complete loss of activity occurring at temperatures above 110°C for 20 min. The effect of different pH conditions on the hemagglutination capacity of leaves protein was readily discernible. The hemagglutination activity of leaves protein was 10 in a pH value from 3.7 to 7.8, and the hemagglutination activity was completely lost at a pH value higher than 11.9. D(+) anhydrous glucose is the specific inhibitory sugar of leaves protein lectin. leaves protein exhibits hemolytic activity at a concentration of at least 20 mg/mL, and α-methyl-mannoside, galactoside, raffinose and Al can inhibit the hemolysis of leaves protein. The present study identified the effects of different factors on the coagulation activity and hemolytic ability of leaves protein, thereby providing a theoretical basis for further purification and application of lectin. However, it should be noted that the results of the mixture have certain limitations, and further purification of lectin is needed to obtain more targeted research results.