Production of geraniol and geranic acid: High value compounds of citral biosynthetic pathway from lemongrass oil using Aspergillus niger AUD-C2 as catalyst

Abstract

Microbial biotransformation of lemongrass oil to geraniol and geranic acid, high value compounds of citral biosynthetic pathway has been reported. Biotransformation studies were carried out using a fungus Aspergillus niger strain AUD-C2 isolated from the rhizospheric soil of lemongrass, as catalyst. Three different methodologies using culture broth, spore suspension and cell-free extract, have been utilized for biotransformation and successfully demonstrated at litre scale in bioreactors. Overall 55% geraniol and 75% geranic acid were obtained by biotransformation of lemongrass oil in 48 h using spore suspension and cell free extract, respectively.

Keywords:

• Aspergillus niger
• lemongrass oil
• citral
• geranic acid
• geraniol

Acknowledgements

The authors are thankful to Director, CSIR-IIIM for his interest in this work. Authors thank QMI Division for providing institutional facilities for GC-MS and NMR studies. The authors express gratitude to Dr. P.P. Singh for helping in NMR spectra analysis. The manuscript bears institutional communication no CSIR-IIIM/IPR/00531.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

DK carried out most of the experiments and wrote the manuscript, RSM performed isolation & characterization of compounds and helped in optimization experiments & formatting of manuscript. AC conceptualized, coordinated, supervised the entire work and finalized the manuscript.

Additional information

Funding

Financial support from CSIR Aroma Mission Phase-3 (HCP-0007) is gratefully acknowledged.