Phenotypic and genotypic characterization of lactococci isolated from different kinds of raw milk (goat, cow, sheep and camel)
Abstract
K. Houbad*, A.M.A. Bekada, A. Homrani and Y. Djellid
Lactococci were isolated from different types of raw milk (goat, cow, sheep and camel) from different regions of Algeria.
From a collection of 254 cocci isolates, only 110 strains representative of the dominant flora were completely identified, by phenotypic methods.
Phenotypic and genotypic identification of these isolates was performed using classical biochemical and physiological methods then by sequencing of the 16S rDNA gene.
A molecular analysis was conducted where the phylogenetic tree was constructed using the Neighbor-Joining method.
The results revealed a dominance of the species Lactococcus lactis subsp. Lactis with a percentage of 41%; followed by Lactococcus lactis subsp. lactis. biovar. diacetylactis (12%), then Lactococcus lactis subsp. hordniae (11%), Lactococcus lactis subsp. Cremoris, Lactococcus plantarum and Lactococcus raffinolactis (10%), and lastly,Lactococcus lactis Subsp.tructae.,lactococcus hircilactis, lactococcus lendensis and lactococcus piscium are found with very low percentage.