Isolation and characterization of a mesophilic cellulolytic endophyte Preussia africana from Juniperus oxycedrus

The medicinal plant Juniperus oxycedrus is less recognized for the diversity of its fungal endophytes and their potential to produce extracellular enzymes. The present study is the first report on the isolation and identification of a mesophilic endophytic strain JO-A, Preussia africana, from fresh stems of the J. oxycedrus endemic tree in the Ifrane region-Morocco, and the evaluation of its ability to produce cellulases. A one-time multi-parameter one-factor screening was optimized to select factors that enhance cellulase production in P. africana. The maximum production of both CMCase and FPase activities were 1.913 IU.mL^-1 and 0.885 IU.mL^-1, respectively, when the medium was supplemented with 2% w/v glucose. These remarkable titers were tenfold greater than those obtained under the initial non-optimized conditions. This mesophilic P. africana JO-A strain grows and actively produces cellulases at 37 °C demonstrating its great potential for various biotechnology applications. The cellulolytic extract showed the highest enzymatic activities at pH 5.0 and 50 °C with a half-life of 24 h at 50 °C.