Process optimization for production and purification of γ-decalactone from ricinoleic acid using Yarrowia lipolytica NCIM 3590

Abstract

γ-decalactone is an industrially relevant aroma compound produced by microbial transformation of ricinoleic acid. Low yields of γ-decalactone owing to toxic concentrations of substrate, formation of competing metabolites and its purification are the major concerns for industrial production. Thus, the current study focuses on improving the microbial yields of γ-decalactone using Yarrowia lipolytica NCIM 3590 by optimizing the parameters of biotransformation. Molar conversion of 75% with 5 g/L ricinoleic acid was achieved using 12 g DCW/L. The highest γ-decalactone productivity of 200 mg/L/h was achieved within 10 h at constant agitation and aeration rate of 200 rpm and 2 vvm, respectively using continuous stirred tank reactor (CSTR). The stationary phase cells used for production can be reused for four cycles without loss of productivities. Further, the produced γ-decalactone was isolated and purified from the biotransformation media using a combination of chromatography and liquid-liquid extraction methods. This three-step purification yields 80% pure γ-decalactone with an overall recovery of 85% of the product. The present study can be used for industrial-scale continuous production of γ-decalactone. • Process optimization for production of γ-decalactone by Yarrowia lipolytica . • Use of optimized conditions to yield 75% molar conversion of 5 g/L ricinoleic acid. • Enhanced γ-decalactone production in Continuous stirred Tank Reactor. • Downstream operation for manufacturing 80% pure γ-decalactone with 85% recovery.