Antioxidant activity and evaluation of lysing cell efficiency from different fractions of lactobacillus acidophilus NCFM®

Several investigations have shown that Lactobacillus acidophilus has antioxidant systems, both in its whole cell and in extract of cell lysate. Thus, this study aimed at evaluating the efficiency of lysing cell to obtain extract of cell lysate, its antioxidant activityas well as intact cells, obtained from Lactobacillus acidophilus NCFM® cultures. Cell lysis was carried out using sonication and centrifugation processes, whose efficiency was measured by plating in depth after obtaining the extract process from cell lysate. The antioxidant activity was measured based on the method of reducing 2.2-diphenyl-1-picryl-hidrazylfree radical (DPPH) with different concentrations of sample and reducing power of ferric-ferrocyanide complex (Prussian Blue). The result was compared to the positive standardButylhydroxytoluene. The results indicated that there was no lysis in extract of cell lysate, and the applied processes only separated the colonies. During the DPPH and Prussian Blue trials, the antioxidant activity increased proportionally to the sample concentration and it was superior in the sample obtained by sonication and centrifugation when compared to intact cells. The non-occurrence of cell lysis may be explained by the fact that Lactobacillus acidophilus has thick cell wall, which may have interfered on ultrasonic forces action.