Abstract

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

Author(s): 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.