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BACKGROUND: Phytopathogenic microorganisms are the main cause of plant diseases, generating significant economic losses for the agricultural and food supply chain. Cherry tomatoes (Solanum lycopersicum var. cerasiforme) are very perishable plants and highly demanding in the use of pesticides; therefore, alternative solutions such as biosurfactants have aroused as a potent substituent. The main objective of the present study was to investigate the antimicrobial activity of sophorolipids against the phytopathogens Botrytis cinerea, Sclerotium rolfsii, Rhizoctonia solani and Pythium ultimum. RESULTS:The biosurfactant inhibited the mycelial growth in vitro with a minimum concentration of 2 mg mL −1 . The application of sophorolipids at 1, 2 and 4 mg mL −1 in detached leaves of tomato before the inoculation of the fungus B. cinerea was the best treatment, reducing leaf necrosis by up to 76.90%. The use of sophorolipids for washing tomato fruits before the inoculation of B. cinerea was able to inhibit the development of gray mold by up to 96.27%. CONCLUSION:The results for tomato leaves and fruits revealed that the biosurfactant acts more effectively when used preventively. Sophorolipids are stable molecules that show promising action for the potential replacement of pesticides in the field and the post-harvest process against the main tomato phytopathogens.

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A B S T R A C TAdsorption experiments were carried out using waste Mexerica mandarin "Citrus nobilis" peel as a new biosorbent to adsorb Cu(II), Cd(II), and Pb(II) ions from aqueous solutions at room temperature. To achieve the best adsorption conditions, the influences of pH and contact time were investigated. The isotherms of adsorption were fitted to the Langmuir and Freundlich equations. Based on the experimental data the adsorption order was Pb(II)>Cd(II) >Cu(II) (in mg g À1 ) on the new biosorbent. This quick adsorption process reached the equilibrium before 20 min, with maximum adsorptions at pH 5.0. Kinetic studies were carried out using the pseudo-first-order and pseudo-second-order models. Thermodynamic aspects of the adsorption process were investigated. The new biosorbent was used in columns for the removal of Cu, Cd, and Pb ions of the samples of industrial effluent and its efficiency and regeneration potential were studied.