Precise fruit glucose determination by a novel peroxidase from the callus of Ocimum Basilicum

Due to the important applications of various peroxidases in biotechnology, medicine and different industries, there is an ongoing research for novel peroxidases [1]. Successful callus induction of Ocimum Basilicum leaves occurred on Murashige and Skoog (M S) medium containing sucrose (1.5%), 2,4-Dichlorophenoxyacetic acid (10-6 M) and kinetin (10-5M) at 25 °C in darkness. Preliminary examinations revealed high peroxidase activity of the callus extract. To proliferate the callus, it was subcultured every 21 days on the same medium. O. basilicum peroxidase was extracted and purified (117.78 fold) through a 4-step procedure. The enzyme showed an average molecular weight of 40 kD. The enzyme reached its maximum activity at optimal range of pH 5–7.5 at 60°C. O. basilicum peroxidase was employed in a comparative study with horseradish peroxidase for the coupled-enzymatic assay of glucose in banana and pear extracts according to Trinder method [2]. D-glucose + O2 + GOX → D-gluconic acid + H2O2 Phenol + 4AAP + H2O2 + POX → Quinoneimine dye + H2O Analysis of the results indicated that O. basilicum peroxidase can be used instead of horseradish