Ikram Medjaoui*1, Bouabdellah Rahmani2, Malika Talhi1,
Fatima Zohra Mahammi1, Fatima Zohra Moghtit1,
Nadhira Mehtar1 and Semir Bechir Suheil Gaouar1,3

1Laboratoire de Genetique Moleculaire et Cellulaire, Departement de Genetique Moleculaire
Appliquée, Faculte des sciences de la nature et de la vie, Universite des Sciences et de la
Technologie d’Oran- Mohamed BOUDIAF-USTOMB-, BP 1505 El M’naouer 31036, Oran, Algeria.
2Departement d’Electronique, Faculte de Genie Electrique, Université d’Oran,
BP 1524. El M’Naouar, 31000 Oran, Algeria.
3Departement de biologie, Universite Abou Bekr Bekaid, Tlemcen, Algeria.

Abstract

Breast milk is a rich source of nutrients. It helps to establish a good intestinal flora of infants. In this context, we have isolated and characterized lactic acid bacteria from human milk and infant feces of the northwest Algerian population (Oran). In the present study, 87 bacterial strains were isolated from breast milk and infant feces samples from 20 mother-infant pairs. Isolates were identified by 16S rDNA sequencing analysis. The results of 16S rDNA sequencing analysis showed that the strains isolated from milk and faecal samples are part of 12 different species belonging to the genera: Enterococcus, Staphylococcus, Streptococcus and Lactobacillus. A homogeneous distribution was found for the four genera in the two media. Also, several mother/infant pairs shared some bacterial species belonging to different bacterial genera. Comparing the intestinal flora of vaginally delivered infants and those born by Caesarean section, a significant difference was found for the genus Staphylococcus (P-value <0.05) with a high rate among infants born by cesarean section. These results indicate that breast milk and delivery mode may contribute to the infant gut colonization.

Keywords: lactic acid bacteria; human milk; infant feces; 16S rDNA sequencing analysis; vaginally delivery; cesarean section.