Enzymatic hydrolysis of Opuntia ficus-indica cladode by Acinetobacter pittii and alcohol fermentation by Kluyveromyces marxianus: pH, temperature and microorganism effect

摘要

In the present work the effect of three factors: pH, temperature and type of microorganism using a factorial design 3sup2/supx2 was evaluated on: growth, total cellulases hydrolytic activity (FPases), endoglucanases hydrolytic activity (CMCases), free reducing sugars (FRS), glucose, sucrose, and alcohol production using a culture medium based on mineral salts added with cladodes flour of Opuntia ficus-indica at 20% as the unique carbon source. Two wild microorganisms were used, Acinetobacter pittii a bacteria isolated from decaying cladodes, and Kluyveromyces marxianus a yeast isolated from termite stomach. The maximum hydrolytic activities were obtained with Acinetobacter pittii at 37?°C and pH 6.5 for total cellulases (0.67?±?0.02 IU/ml) and for endoglucanases (0.23?±?0.02 IU/ml) at 24 and 4?h. The maximum production of alcohol was 12.98?±?0.06?g/L obtained with Kluyveromyces marxianus at 4?h with conditions of 40?°C and pH 5.5.