Hydroxylation of 1,8-cineole by Mucor ramannianus and Aspergillus niger

• Published in: Brazilian journal of microbiology Vol. 46; no. 1; pp. 261 - 264
• Main Authors: Ramos, Aline de Souza, Ribeiro, Joyce Benzaquem, Teixeira, Bruna Gomes, Ferreira, José Luiz Pinto, Silva, Jefferson Rocha de A, Ferreira, Alexandre do Amaral, de Souza, Rodrigo Octavio Mendonça Alves, Amaral, Ana Claudia F
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Microbiologia 01-03-2015
• Subjects: Aspergillus niger - metabolism; Cyclohexanols - metabolism; Eucalyptus - chemistry; Hydroxylation; Industrial Microbiology; Monoterpenes - metabolism; Mucorales - metabolism; Time Factors; Trichoderma - metabolism; biotransformation; Mucor ramannianus; monoterpene; Aspergillus niger; 1,8-cineole
• ISSN: 1678-4405; 1517-8382; 1678-4405
• DOI: 10.1590/S1517-838246120131020

The monoterpenoid 1,8-cineole is obtained from the leaves of Eucalyptus globulus and it has important biological activities. It is a cheap natural substrate because it is a by-product of the Eucalyptus cultivation for wood and pulp production. In this study, it was evaluated the potential of three filamentous fungi in the biotransformation of 1,8-cineole. The study was divided in two steps: first, reactions were carried out with 1,8-cineole at 1 g/L for 24 h; afterwards, reactions were carried out with substrate at 5 g/L for 5 days. The substrate was hydroxylated into 2-exo-hydroxy-1,8-cineole and 3-exo-hydroxy-1,8-cineole by fungi Mucor ramannianus and Aspergillus niger with high stereoselectivity. Trichoderma harzianum was also tested but no transformation was detected. M. ramannianus led to higher than 99% of conversion within 24 h with a starting high substrate concentration (1 g/L). When substrate was added at 5 g/L, only M. ramannianus was able to catalyze the reaction, but the conversion level was 21.7% after 5 days. Both products have defined stereochemistry and could be used as chiral synthons. Furthermore, biological activity has been described for 3-exo-hydroxy-1,8-cineol. To the best of our knowledge, this is the first report on the use of M. ramannianus in this reaction.