Lectins are carbohydrate-binding proteins that play vital roles in many biological processes. In this study, lectins from three Egyptian cultivars (fava bean, lentil, and pea) were isolated by precipitation with different concentrations of ammonium sulfate. The purification process was performed by affinity chromatography using mannose agarose. The highest concentration of purified lectins (1.48 mg/g) was recorded in pea at 90% saturation. SDS-PAGE of the purified lectins revealed bands of low molecular weights (14 to 18 kDa). The complete amino acid sequences of purified lectins were assessed using mass spectrometry (MS), which indicated the presence of the peptides favin, p54, and psl in fava bean, lentil, and pea, respectively. The lectins showed antimicrobial activity. The highest inhibition zone (35 mm) was measured with lectin purified from lentil against Staphylococcus aureus ATCC 6538, followed by pea lectin (33.4 mm) against Pseudomonas aeruginosa ATCC 10145. To the best of our knowledge, the legume lectins in this study are the first lectins to exhibit antifungal activity against Candida albicans, with the maximum inhibition zone (25.1 mm) observed with purified lectins of fava bean. Additionally, the first scanning electron microscope (SEM) images showing agglutination and clumping of microbial cells exposed to tested lectins are provided. These findings proved that Egyptian legume lectins are distinct from other lectins reported in previous studies and demonstrated their potential as antimicrobial agents against human pathogenic microorganisms.

Seeds of tomato (Lycopersicon esculentum Mill., variety Castle Rock) were osmoprimed in polyethylene glycol 6000 (PEG; 20%) or K 2 HPO 4 (200 mM) solution for 8 hours, 3 days or 7 days, while another group of seeds were left in water for the same periods. The GA 3 /ABA ratio was the most important hormone factor, which promoted germination in seeds soaked in H 2 O and led to improved germination performance. This ratio showed slight variations between hydroprimed and osmoprimed seeds after 8 hours, but afterwards, from 3 to 7 days, it was gradually increased in the osmoprimed seeds and was substantially elevated in seeds germinating in H 2 O. Changes in the concentrations of phenolic compounds suggested their possible role in germination silencing in the osmoprimed seeds, but at relatively low concentrations. Protein patterns showed no marked variations in hydroprimed and osmoprimed seeds after 8 hours, but different types were observed, particularly after 7 days. A comparison of the protein banding patterns of seeds after 1 day and 7 days in the osmoconditioning solutions (PEG or K 2 HPO 4 ), H 2 O, GA 3 or ABA showed certain treatment-specific protein bands, particularly in PEG and ABA solutions. Longitudinal sections of seeds (after 3 days) showed lysis of the micropylar endosperm and radicle protrusion in H 2 O or GA 3 , whereas in PEG or K 2 HPO 4 solution the radicle expanded inside the seed and the micropylar endosperm was completely intact. In ABA solution, the whole endosperm was compact and the seed became extensively desiccated.

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T HIS STUDY aimed to investigate the physiological and biochemical responses of common bean (Phaseolus vulgaris L. cv. Valentino) plants grown in virgin sandy soil incorporated with ceramic wastewater sludge (CWWS), at relatively low concentrations (0.5%, 1% and 2%), for 30 days. Within the different levels used of CWWS, especially at 1%, the enhancement of plants growth was generally proportional with the increase in leaf area and chlorophyll content, as well as it associated with higher uptake of P, N and K due to higher content of these metals in the CWWS-amended soil. Sucrose, proline and malondialdehyde (MDA) showed enhanced levels with the increase of CWWS application, while, glutathione (GSH) content of common bean plants showed attenuated levels. These results were in alliance with accumulation of higher levels of Fe and Cu metals inside the plant tissues. Antioxidant enzymes such as catalase (CAT), polyphenol oxidase (PPO), showed significantly enhanced activities with increasing the amended ratio of sludge. This increase was also accompanied with the increase in ascorbic acid (AsA) and total phenol contents and a decrease in the activities of ascorbate oxidase (ASO) and ascorbate peroxidase (APX).