Contribution à l’étude des bactéries extrêmophiles sporogènes isolées à partir des sols de trois régions sahariennes: Adrar, In Amenas et El Méniâa

Abstract

This study is carried out in the laboratory of the University of Ghardaia to highlight the phenotypic and biochemical characterization of sporogenic extremophilic bacterial strains isolated from the soils of palm groves of three Saharan regions: Adrar, In Amenas and El-Meniâa. The isolation of the strains was carried out on TSA (Trypticase Soy agar) culture medium and the strains were incubated under different physico-chemical conditions for 7 days to isolate the thermophilic strains, and for 60 days to isolate the alkalophilic strains and halophiles. Morphological and biochemical pre-identification of isolate T101 indicated that this isolated strain is Gram positive, and has a rod-like, motile, catalase + form, and suggests that it may be affiliated with the genus Bacillus or another genus close. The physicochemical parameters (temperature, pH and NaCl concentration of the T101 isolate) are optimized by the conventional method, and the results obtained have shown that the temperature optimum is 25 ° C, the pH optimum is 7 and the optimum of the NaCl concentration is 0%. In addition, we used the API 20E gallery to get an idea about the classification of the strain T101 different program were used to determine the similarity percentage of the T101 trash with the species listed in these databases. The Excel Identification Program (EIP) suggests that the T 101 strain is 69.3% Bacillus sphaericus / fusiformis / badiu. While the ABIS online program identifies the strain as Bacillus coagulans with a probability score of 68%. On the other hand, Bacterial Identification Program (BIP Win) identification suggests that the T 101 strain is a 100% Bacillus firmus type1.