First report of collagenase production by Trichosporon sp. strain isolated from pollen of Amazonian bee (Melipona seminigra seminigra)

Abstract

Trichosporon yeasts are widely employed to produce lipids, lipases, and aspartic peptidases, but there are no previous studies on collagenase production. This work aimed to select the best collagenase producing Amazonian Trichosporon strains. Moreover, a 2³-full factorial design (FFD) and a 2²-central composite design combined with Response Surface Methodology were applied to optimize production and find the best conditions for hydrolysis of type I bovine collagen. Most of the studied strains had some collagenolytic activity, but the selected one achieved the highest value (44.02 U) and a biomass concentration of 2.31 g/L. The best collagenase production conditions were 160 rpm of agitation, pH 5.5 and a substrate concentration of 4.0 g/L. The former experimental design showed that substrate concentration was the only statistically significant factor on both biomass concentration and collagenase activity, while the latter showed simultaneous effects of substrate concentration and pH on collagenolytic activity, which peaked at pH 5.5–6.4 and substrate concentration of 3.0–3.4 g/L. An additional 2³-FFD was finally used to optimize the conditions collagen hydrolysis, and pH 6, 25 °C and a substrate concentration of 7.5 (g/L) ensured the highest hydrolysis degree. This study is the first that describes optimized conditions of collagenase production by Trichosporon strains.

Keywords:

• Collagenolytic protease
• factorial design
• optimization
• RSM
• yeast

Acknowledgments

The authors would like to thank the mycotheca of the Federal University of Amazonas, Brazil (DPUA/UFAM) for the yeast strains.

Additional information

Funding

This work was supported by the Brazilian National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico [CNPq]), Universal Grant-014/2013. Douglas F. Silva and Emerson P. de Souza are grateful to CNPq for their Scientific Initiation (IC) grant.