Development of process conditions for biodegradation of raw olive mill wastewater by Rhodotorula glutinis

• Published in: International biodeterioration & biodegradation 2012-11, Vol.75, p.75-82
• Main Authors: Karakaya, Alper, Laleli, Yahya, Takaç, Serpil
• Format: Article
• Language: English
• Subjects: Biodegradation; cell growth; centrifugation; Dephenolization; Olea; Olive mill wastewater; olive oil; olives; phenol; Rhodotorula glutinis; urea; wastewater; yeasts
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/j.ibiod.2012.09.005

Olive mill wastewater (OMW) generated during olive oil production has detrimental effects on environment arising from its high phenolics content. This study has focused on finding operational conditions of a process that biodegrade undiluted, un-pretreated and non-supplemented OMW that is raw OMW by nonconventional yeast Rhodotorula glutinis with a high dephenolization degree. The pH of OMW medium increased in accordance with cell growth and dephenolization. High initial medium pH provided by urea resulted in high phenol removal. Sterilization and centrifugation of OMW before biodegradation have no considerable effects on phenol removal. Better results were obtained at 30 °C and 150 rpm as compared to their lower values. Reduction of 89% in total phenol concentration in raw OMW was obtained in batch-wise operation where pH of the medium increased up to 8.9. The important novelty presented in this report deals with the utilization of raw OMW in biodegradation by R. glutinis. ► Olive mill wastewater provided a high reduction (up to 91%) in total phenol concentration by nonconventional yeast Rhodotorula glutinis. ► R. glutinis was successful in biodegradation of OMW without a need of dilution and additional treatment. ► The pH of medium had the most significant effect on biodegradation.