Abstrait

Morphological criteria artichoke Cynara scolymus L. grown in the region of Kenitra in Morocco

M.Sobh, N.Rhaiem, N.Chaouche, R.Bengueddour, A.Hammoumi, O.Belghazi, M.Ouhssine

Kefir is fermented milk only made from kefir grains and kefir cultures and nowadays consumed widely around the world. It may become contaminated with aflatoxin M₁ (AFM₁) which even in small quantities, have hazardous effects for human beings. Therefore, a practical and effective method is needed to be developed for the detoxification of AFM₁ contaminated milk or decreased its toxicity. It has been reported that specific lactic acid bacteria are able to remove or degrade AFM₁ from liquid media by physical binding. The objective of this study was to detect the effect of kefir starter and Lactobacillus acidophilus to bind AFM₁ in kefir made from milk spiked with 500 pg AFM₁ mL^-1. Accordingly, five levels of kefir starter (2‚ 4‚ 6%‚ 8 and 10%) as group 1 and five levels of Lb. acidophilus (0.1‚ 0.3‚ 0.5‚ 0.7 and 0.9%) with constant amount of kefir starter (4%) as group 2 were used. After 48h, the AFM₁ content of kefir samples was measured by competitive ELISA technique. Statistical analyses‚ in group 1‚ showed that the sample containing 6% kefir starter had the most reduction in AFM₁ concentration (88.17%) which was significant (p<0.05). In group 2 the sample containing 0.9% Lb. acidophilus and 4% kefir starter had the maximum amount of AFM₁ binding (89.04%) and there were no significant differences (p<0.05) between 0.3‚ 0.5 and 0.7% levels in AFM₁ reduction. Generally‚ the effect of kefir starter (alone) was more than Lb. acidophilus in AFM₁ binding and the combination of these strains had synergistic effect in AFM₁ reduction. These findings affirmed that particular bacteria and yeast used in this study can offer decontaminating AFM₁ kefir.