Optimization of biomass production of a new morphological and biochemical mutant of Yarrowia lipolytica with an increased lipase activity using raw glycerol”

IANNONE L.J; GALVAGNO M.G.; BIANCHI J; ROST E; CARSTENS MR; CERRUTTI P

REVISTA ARGENTINA DE MICROBIOLOGíA

ASOCIACION ARGENTINA MICROBIOLOGIA

Lugar: Buenos Aires; Año: 2011 vol. 43

0325-7541

The yeast Yarrowia lipolytica accumulates oils and is able to produce extracellular lipases when growing in different carbon sources including glycerol, principal by-product from the increasing biodiesel industry. In this study, biomass production of a novel mutant strain of Y. lipolytica was statistically optimized by Response Surface Methodology in media containing biodiesel derived glycerol as main carbon source. This strain exhibited distinctive morphological and quali-quantitative fatty acid content characteristics, and showed an increased extracellular lipase activity. An organic source of nitrogen and the addition of 1.0 g/l olive oil were necessary for significant lipase production. Plackett-Burman and Central Composite Statistical Designs were employed for fermentation optimization in shaken flasks cultures and the maximal values obtained were 16.1 g/l for biomass and 12.2 Units/ml for lipase, respectively. Optimized batch bioprocess was thereafter scaled in aerated bioreactors and the values reached for lipase specific activity after 95% of the glycerol has been consumed, were three fold higher than the obtained in shaken flasks cultures. A sustainable bioprocess to obtain biomass and extracellular lipase activity was attained, by maximizing the use of the by-products of biodiesel industry.