Olive-mill wastewaters: a promising substrate for microbial lipase production

• Published in: Bioresource technology 2006-10, Vol.97 (15), p.1828-1833
• Main Authors: D’Annibale, Alessandro, Sermanni, Giovanni Giovannozzi, Federici, Federico, Petruccioli, Maurizio
• Format: Article
• Language: English
• Subjects: Aspergillus niger; Biological and medical sciences; Candida - metabolism; Candida cylindracea; Food industries; Food Industry; Fundamental and applied biological sciences. Psychology; Fungal screening; Fungi - metabolism; Industrial Microbiology - methods; Industrial Waste; Lipase - metabolism; Lipase production; Medium optimization; Nitrogen - metabolism; Olive Oil; Olive-mill wastewater valorization; Plant Oils; Time Factors; Use and upgrading of agricultural and food by-products. Biotechnology; Waste Disposal, Fluid; Waste Management
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2005.09.001

The present study investigated the valorization of olive-mill wastewater (OMW) by its use as a possible growth medium for the microbial production of extra-cellular lipase. To this end, strains of Geotrichum candidum (NRRL Y-552 and Y-553), Rhizopus arrhizus (NRRL 2286 and ISRIM 383), Rhizopus oryzae (NRRL 6431), Aspergillus oryzae (NRRL 1988 and 495), Aspergillus niger (NRRL 334), Candida cylindracea (NRRL Y-17506) and Penicillium citrinum (NRRL 1841 and 3754, ISRIM 118) were screened. All strains were able to grow on the undiluted OMW, producing extra-cellular lipase activity. C. cylindracea NRRL Y-17506 showed the highest lipase activity on all the typologies of OMW used. Its lipase production on OMW was markedly affected by the type of nitrogen source and was induced by the addition of olive oil. The highest activity (9.23 IU ml −1) of the yeast was obtained on OMW supplemented with NH 4Cl (2.4 g l −1) and olive oil (3.0 g l −1).