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| Author(s): |
Marina Gabriel Pessôa
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos |
| Defense date: | 2017-11-10 |
| Examining board members: |
Glaucia Maria Pastore;
Francisco Fabio Cavalcante Barros;
Gustavo Molina;
Mário Roberto Maróstica Junior;
Rosana Goldbeck
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| Advisor: | Glaucia Maria Pastore |
| Abstract | |
This work aimed to prospect novel fungal biocatalysts to be employed in biotransformation of terpenes (R-limonene, S-limonene, 'alpha'-pinene, ß-pinene e citronellol) for natural aroma production, as well as the optimization of process conditions in order to increase final product concentration. Initially, the practical work comprised the isolation of endophytic microorganisms and the screening of the best strains for bioflavors production. These microorganisms were isolated from unripe genipap (Genipa americana L.) fruits, a Brazilian unexploited source of monoterpenes and iridoids. Fifteen endophytic filamentous fungi strains were isolated from unripe genipap, from which, three strains showed the ability to metabolize the tested monoterpenes. A strain identified as JV-7 was able to bioconvert 'alpha'-pinene into verbenol and verbenone, interesting compounds for flavors and fragrance industries. In the biotransformation of ß-pinene, the major product obtained was pinocarveol, using the strain JV-15. Pinocarveol has higher reference price when compared to its precursor, and, there are few works regarding its production. The isomers of limonene were metabolized by JV-10 strains and two different products could be obtained: neodihydrocarveol and limonene-1,2-diol, from R- and S-limonene respectively. Aiming to increase final product concentration obtained with endophytic strains, the variables agitation, temperature, substrate concentration and amount of biocatalyst biomass were evaluated in two experimental designs. In the first central composite design (CCD), the biotransformation of 'alpha'-pinene into verbenol could be optimized using the process conditions: 200 rpm, 22 ºC, substrate concentration of 1.25 % (v/v) and fungal biomass of 5 g in 50 mL media, increasing verbenol concentration from 222.4 ± 2 mg/L to 318.4 ± 2.4 mg/L. The second CCD, aimed to optimize ?-pinene biotransformation for pinocarveol production. In this case, the optimum conditions were substrate concentration of 1% (v/v), 150 rpm, 30 ºC and 5g of fungal biomass per 50 mL media. It was achieved a 2-fold increase in pinocarveol concentration, from 64.8 ± 0.6 mg/L to 141.32 ± 2.6 mg/L. The study of process parameters for natural aroma production is one of the most promising tools that are being used to increase product concentration and consequently to reduce costs in its production. In addition, this work shows the potential of endophytic microorganisms that can be naturally found in terpene rich sources to be employed as new biocatalysts in biotransformation assays, obtaining extracts with novel and interesting sensorial characteristics (AU) | |
| FAPESP's process: | 13/18390-0 - Study of the genes involved in the biotransformation of terpenes for natural flavors production |
| Grantee: | Marina Gabriel Pessôa |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |