Bioproduction of α-terpineol and R-(+)-limonene derivatives by terpene-tolerant ascomycete fungus as a potential contribution to the citrus value chain

VELAZQUEZ J. E.; SADAÑOSKI M. A.; ZAPATA P. D. ; COMELLI N. A. ; VILLALBA L. L.

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020

1364-5072

Aims: The aims of this article were to select fungal species with high toleranceand high growth rate in mediums supplemented with limonene and citrusessential oils (CEOs), and to test the bioconversion capability of the chosenisolates for the bioproduction of aroma compounds.Methods and Results: Based on the use of predictive mycology, 21 of 29isolates were selected after assaying R-(+)-limonene and CEO tolerance(10 g l−1). With a dendrogram divisive coefficient of 0937, the subcluster twowith isolates Aspergillus niger LBM 055, Penicillium sp. LBM 150, Penicilliumsp. LBM 151 and Penicillium sp. LBM 154 gathered the highest tolerance andmycelia growth speed. Ultrastructural analysis indicated that culture mediacontaining limonene had no visible toxic activity that could promotemorphological changes in the fungal cell wall. The biomass of A. niger LBM055was distinctive in liquid media supplemented with R-(+)-limonene(057 007 g) and it was selected to prove bioconversion capacity, understatic and agitated conditions, and converted up to 98% of limonene, yieldinga wide variety of products that were quantified by GC-FID. It was obtained atmolecular weights less than limonene (64?100%), between limonene and α-terpineol (12?72%) and greater than α-terpineol (2?48%).Conclusions: Aspergillus niger LBM 055, Penicillium sp. LBM 150, Penicilliumsp. LBM 151 and Penicillium sp. LBM 154 showed to the highest tolerance andgrowth rate in mediums supplemented with R-(+)-limonene and orange andlemon essential oils. Particularly, A. niger LBM055, showed limonenebioconversion capability and produced different molecular weights compoundssuch us α-terpineol.Significance and Impact of the Study: Different bioproducts can be obtainedby changing operative condition with the same fungus, and this bioprocessaspect is a significant approach to be adopted on industrial scale leading to thecreation of new natural flavours and fragrance compositions.