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L’adsorption du Victoria Bleu Basique (VBB) sur du carton usagé (CU) a été étudiée et comparée à celle sur de la sciure de bois (SB). Le CU a été caractérisé par différentes techniques analytiques. Les paramètres influençant la réaction ont été déterminés, tels que le pH, le dosage des adsorbants et le temps de contact. L’étude cinétique a révélé que la réaction de surface s’adapte au modèle de pseudo-second ordre et que la diffusion intraparticulaire est une étape déterminante après les premières minutes. L’influence de la température sur l’adsorption a permis de déterminer les paramètres thermodynamiques (∆G°, ∆H° et ∆S°). La modélisation des résultats expérimentaux prédit une chimisorption spontanée, endothermique dont la rétention se fait suivant un mécanisme intermédiaire, entre une distribution en monocouche et celle en multicouche, sur le CU. À pH 6 la capacité d’adsorption du CU, égale à 205 mg∙g-1, est cinq fois supérieure à celle de la SB.

The use of lactic acid bacteria (LAB) in the dairy industry has undergone an enormous evaluation in technologically advanced countries. The exploitation of this kind is however very limited in some other countries such as Algeria. This limitation concerns the diversity of products present on the market but also the number of strains introduced in dairy products, this is related to the constraints posed by LAB. To isolate new probiotic strains, samples of cow's milk were subjected to spontaneous fermentation to enrich its LAB. 21 lactic acid isolates active against four pathogenic and food spoilage bacteria were selected from sixty-one isolated LAB, and only ten strains were selected showing considerable adhesive capacities. Indeed, they have moderate to high levels of hydrophobicity. They can all auto-aggregate with percentages ≥85.86 ± 0.59%. The power to co-aggregate with 4 pathogenic strains differs from strain to strain. Thus, strains C2, H9, V5, and L7 showed different percentage levels of 56.06 ± 0.36%, 32.33 ± 0.63%, 22.60 ± 079%, and 6.55 ± 0.20% against B. cereus, S. aureus, P. aeruginosa, and E. coli respectively. They were all resistant to the acidity of the stomach environment and have a good tolerance to 0.3% and 0.5% bile salts. All isolates were able to grow at 0.4% phenols after exposure for 24 h. Only our lactic acid bacteria V1 and V8 showed resistance after exposure to pepsin at pH =2 and all strains at pH =3. The results obtained are interesting which makes our strains presumed probiotic, they can play an important role in the gastrointestinal tract (GIT).

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