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Abstract Lectins have drawn the attention of many researchers recently due to their diverse biological properties. This attracted the attention of using lectins in many areas including Science, Medicine, Pharmacy, and Biotechnology. In this study, lectins from ten leguminous seeds (Fava bean, Lentil, Lima bean, Pea, Soy bean, and five cultivars of Phaseolus vulgaris) were isolated by ammonium sulfate precipitation at saturation (30%,70%,90%) followed by dialysis process overnight in phosphate buffer (pH 7.2) at 4°C.The results showed that the highest significant concentration values of lectins recorded in Soy bean, and Lima bean (at 90% fractions) were 14.973, and 13.237 mg/g respectively followed by Pea (10.64 mg/g). In case of the tested Phaseolus cultivars, the highest significant values were recorded (at 90% fraction) with Shalatine (9.467 mg/g) followed by10YLHJ49 (7.167mg/g), Diacole (6.133 mg/g), and Contender (5.567 mg/g). According to similarity in sugar binding, purification process using affinity chromatography was performed to Fava bean, Lentil, and Pea. It was cleared that the highest significant yields of purified lectins were in case of Pea seeds (1.4863 mg/g) followed by Fava bean (0.5047mg/g), andSDS-PAGE was used to detect the molecular weight of lectins, and the results showed that legume lectins are found on the expected regions (range 17-31 kDa). Furthermore, Hemagglutination activity of lectins against all human blood groups (A, B, AB, and O) was recorded. It was found that the legume lectins agglutinated all human blood cells. Moreover, Inhibition of hemagglutination was carried out using sugars (galactose, glucose, maltose, mannose, and sucrose), and the results indicated that lectins from Lima bean, and Soy bean were inhibited by one sugar (galactose) and lectins from Fava bean, Lentil, and Pea were inhibited by two sugars (glucose and mannose sugars). The purified 90% fractions of Fava bean, Lentil, and Pea were similar in their hemagglutination inhibition to that of their dialysed forms since, all of them are inhibited by glucose and mannose sugars. In case of Phaseolus cultivars, the results showed that galactose and mannose inhibited the agglutination activity of all the five tested lectins. Maltose inhibited the hemagglutination activity of lectins from seeds of cultivars. Contender, Diacole, and 10YLHJ49. The examination of antimicrobial activities of lectins was performed using agar-well diffusion method. The results showed that all lectins from leguminous seeds emonstrated a remarkable antibacterial activity against all tested bacteria Staphylococcus aureus ATCC 6538, Streptococcus mutants ATCC25175, Pseudomonas aeruginosa ATCC 10145, and Klebsiella. on other hand Escherichia coli 0157: HZ ATCC 51659 was not inhibited. Lectins also had a potent antifungal activity against Candida albicans. The largest significant inhibition zone diameters (38.5 & 25.2 mm) were recorded in 90%fraction of Soy bean, and Lima bean respectively against Pseudomonas aeruginosa. Also, the inhibition zone diameters were recorded with 90% fraction (37, 34, and 29 mm) of the lectins of cultivars, Shalatine, Diacole, and Contender respectively against Pseudomonas aeruginosa. Lectins purified from Lentil seeds gave inhibition zone diameter of 35 mm against Staphylococcus aureus followed by that of Pea seeds (33.5 & 29.5 mm) against Pseudomonas aeruginosa, and Klebsiella pneumonia respectively. All purified lectins from Fava bean, Lentil, and Pea had antifungal effect against Candida albicans and the highest inhibition zone diameter occurred in Fava bean (25mm). The Minimum Inhibitory Concentration (MIC) test was performed to all dialysed lectin (90% fractions) under study, and the results showed that the lowest values were reported (1.95 μg/ml) in Lentil against Staphylococcus aureus, and in Lima bean against Klebsiella pneumonia and Candida albicans. As far as we are aware, our work is the first approach that showed photographs of scanning electron microscope (SEM) before and after treatment (90% fraction) of the lectins extracted from the Egyptian Shalatine seeds against Staphylococcus aureus and Pseudomonas aeruginosa. Also, legume seeds (Fava bean/ Sakha 1, Lentil/ Giza 51, and Pea/ master Pea 38) against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans respectively. The photomicrographs showed agglutination and clumping of tested bacterial and fungal cells and change in the shape and size of microbial cells. In many cases destruction of microbial cells was also observed. This finding indicates that legume lectins considered to be used in the biotechnology as an alternative way to inhibit the growth of human pathogenic microorganisms. Lentil (0.4830 mg/g). |