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Lactic bacteria are used in fermentation and food bio‐preservation through their production of organic acids and other antimicrobial substances like bacteriocins which restrain certain fungal strains. The main objective of this study is the isolation of Lactobacillus strains from curdled milk samples, in order, to inhibit, in vitro, mycotoxins production by Aspergilus flavus. Six bacterial isolates were obtained from curdled milk commercialized in the region of Constantine. Among them, one isolate coded (B6) had a significant inhibitory effect against A. flavus (the diameter of colony not exceeding 1.5 cm after 72 hr of incubation at 28°C). This isolate (B6), was identified morphologically and biochemically. The obtained results showed that this bacterial isolate belongs Lactobacillus genus. In addition, its antimycotoxinogen activity had been confirmed using some test bacteria, such as E. coli, Staphylococcus aureus, Klebsiella sp., and Pseudomenas syringae. PRACTICAL APPLICATIONS: This paper describes the isolation of lactic bacteria strains from Algerian curdled milk and the study of their antifungal and antimycotoxinogen activity. The method used to test the effect of lactic bacteria strains against toxigenic fungi was not previously exploited. The main objectives were to: (a) Isolate and select the lactic bacteria from curdled milk; (b) Isolate and identify the toxigenic fungi; (c) Select bacterial isolates for antifungal effect against toxigenic fungi; (d) Study of their antimycotoxinogen activity, in vitro.

A modified two-step seeded polymerization was used for the preparation of porous mono-sized microspheres of poly(ethylene glycol dimethacrylate-co-1-vinylimidazole) [poly(EGDMA-co-VIM)] of 7 mu m in size. The specific surface area and the EGDMA/VIM molar ratio of the microspheres were determined as 64.5 m(2)/g and 1.5:1.0 mol/mol, respectively. The adsorption of Pb(II) ions from aqueous solution onto the porous mono-sized poly(EGDMA-co-VIM) microspheres was examined. The maximum adsorption capacities of the microspheres towards Pb(II) ions were determined as 21.74, 30.52, 49.23 and 56.48 mg/g at 293 K, 303 K, 318 K and 338 K, respectively. The dynamic and equilibrium adsorption behaviours of the system were adequately described by the pseudo-second-order kinetic model and the Langmuir isotherm, respectively. The apparent activation energy was determined as 6.212 kJ/mol, which is characteristic of a chemically controlled reaction. The values of E-fe obtained from the Dubinin-Radushkevich equation in the non-linear form were 9.153 kJ/mol at 293 K, 10.34 kJ/mol at 303 K, 10.18 kJ/mol at 318 K and 10.91 kJ/mol at 333 K, thereby indicating that the adsorption of Pb(II) ions onto the porous mono-sized poly(EGDMA-co-VIM) microspheres occurred via a chemical process at all the temperatures studied. Various thermodynamic parameters, such as the Gibbs' free energy change (Delta G(0)), the standard enthalpy change (Delta H-0) and the standard entropy change (Delta S-0) were also determined. The thermodynamic parameters obtained indicated that the adsorption process was endothermic in nature. These results demonstrate that the material studied could be used as a purifier for the removal of Pb(II) ions from water and wastewater.