Utilization of an Industry Byproduct, Corymbia maculata Leaves, by Aspergillus terreus to Produce Lovastatin

Due to its ability to lower cholesterol levels, simvastatin is a leading drug for the prevention of strokes and heart disease: it also lowers the incidence of neurodegenerative diseases. Simvastatin is made from lovastatin, a precursor produced by the industrial fungus, Aspergillus terreus. In this study, Corymbia maculata leaves were tested as a novel substrate for the growth of a new isolate of A. terreus and a lovastatin-resistant strain of A. terreus to produce lovastatin. Corymbia maculata (spotted gum) is well utilized by forest industries as a source of timber because of its high strength, durability and smooth texture. However, the leaves are a major waste product. Growth of A. terreus on Corymbia maculata leaves, in solid-state fermentation resulted in the production of lovastatin. Fermentation of media using fresh leaves of Corymbia maculata produced more lovastatin (4.9 mg g^-1), than the sun-dried leaves (3.2 mg g^-1). Levels of lovastatin were further increased by the lovastatin-resistant strain of A. terreus (Lvs-r), which produced twice the amount of the parental strain. The production of lovastatin was confirmed by HPLC and LC-MS/MS studies. The study suggests that the utilization of a cheap substrate for the production of lovastatin can have a potential economic benefit.

Keywords: Aspergillus terreus; SSF; SmF; eucalyptus; fermentation; lovastatin.