---

Gamma-decalactone, an intramolecular 4-hydroxydecanoic acid ester, has a peach-like aroma and is widely used in the food and cosmetics industries. The biotechnological production of this compound is possible via biotransformation of castor seed oil by the yeast Yarrowia lipolytica. This study aimed to compare the production of gamma-decalactone by wild-type strain with that in a mutant strain producing lipase in high amounts. It was found that cells with yeast-like morphology produce more gamma-decalactone than hyphae-like cells. The maximum production of gamma-decalactone by wild-type and mutant strains was 65 mg/L after 24h of inoculation and 90 mg/L after 72h of inoculation, respectively. The mutant strain converts 38% more substrate into gamma-decalactone than the wild-type strain, therefore, it could significantly increase the productivity of industrial-scale production of gamma-decalactone.