Effect of Bacterial Adaptation on Performance of Ralstoniaeutropha in Olive Oil mill Wastewater Degradation

Olive oil mill wastewater (OMW), arises from the production of olive oil in olive mills, has a very high organic load, recalcitrant compounds like phenolics with a high amount of toxicity/phytotoxicityassociated compounds. The biological process for OMW treatment is based on an aerobic detoxification step followed by methanization step and aerobic post-treatment. But first of all these steps, adaptation phase seems indispensable to prepare the bacteria for the main biotreatment process. Good adaptation procedure would result in better efficiency of the biodegradation process in means lower time required for treatment, higher biodegradation rates, high enzyme induction, and higher removal of organic compounds. For this purpose in this work the adaptation of Ralsonia eutropha bacterium was performed in an airlifr reactor with net draft tube (ALR-NDT) using stepwise procedure. The more diluted form of OMW was used at first and step by step the higher concentrations were used as growth medium for the test bacterium. The Ralstonia eutropha utilized the total phenolics (TP) as carbon and energy source andits efficiency was improved after each adaptation step. Final TP removal percent was about 42% for the undiluted OMW medium and 60% for diluted medium

Keywords:

Adaptation , Ralstonia eutropha , OMW , Total phenol