Analysis of the sensitization activity of Moringa oleifera leaves protein

The determination of allergenic proteins in <i>Moringa oleifera</i> leaves, which is the main components of immune activity, has enabled the development of a more effective method for evaluating the activity of extracted <i>Moringa oleifera</i> leaves protein. In this study, the extraction process of <i>Moringa oleifera</i> leaves protein was optimized based on a single factor experiment. The hemagglutination-related properties of <i>Moringa oleifera</i> 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 <i>Moringa oleifera</i> 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 <i>Moringa oleifera</i> leaves protein was readily discernible. The hemagglutination activity of <i>Moringa oleifera</i> leaves protein was 10⁴ 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 <i>Moringa oleifera</i> leaves protein lectin. <i>Moringa oleifera</i> leaves protein exhibits hemolytic activity at a concentration of at least 20 mg/mL, and α-methyl-mannoside, galactoside, raffinose and Al³⁺ can inhibit the hemolysis of <i>Moringa oleifera</i> leaves protein. The present study identified the effects of different factors on the coagulation activity and hemolytic ability of <i>Moringa oleifera</i> leaves protein, thereby providing a theoretical basis for further purification and application of <i>Moringa oleifera</i> 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.