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Published on: October 24, 2016
Pectinolytic activity secreted by yeasts isolated from fermented citrus molasses
K F Oliveira1, L Malavolta, C S Souza
1Curso de Pós-Graduação Interunidades em Biotecnologia-USP/I. Butantan/IPT, ICB, USP, São Paulo, Brazil.
Journal of Applied Microbiology
|March 24, 2006
Summary
Researchers developed improved pectinolytic yeast strains for industrial ethanol fermentation from citrus molasses. These selected Saccharomyces strains exhibit enhanced pectinase activity, crucial for efficient bioconversion processes.
Area of Science:
- Industrial Microbiology
- Biotechnology
- Enzyme Technology
Background:
- Baker's yeast (Saccharomyces) is used in industrial fermentation.
- Citrus molasses is a substrate for ethanol production.
- Pectinolytic enzymes are important for breaking down pectin.
Purpose of the Study:
- To obtain improved pectinolytic yeast strains.
- To adapt yeast for continuous industrial fermentation of citrus molasses into ethanol.
- To investigate pectinase activity in yeast.
Main Methods:
- Continuous industrial fermentation of citrus molasses.
- Isolation of yeast strains from fermentation process.
- Culturing yeast on pectin-containing media (solid and liquid).
- Assessing pectinase activity via secretion haloes and liquefaction.
Main Results:
- Commercial baker's yeast initially showed no secreted pectinase activity.
- Yeast isolates with pectinolytic activity were obtained from the fermentation process.
- Pectinase secretion was influenced by galactose and colony aging.
- Pectinolytic activity was observed in both cell-wall linked and supernatant fractions.
Conclusions:
- Yeast isolates secreting pectinolytic activity dominated the citrus molasses fermentation.
- Plate secretion halo size did not always correlate with liquid pectinolytic activity levels.
- Selected Saccharomyces strains can serve as a source of pectinases for various applications.
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