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Optimization of
biomass and dihydroorotase (DHOase) production by
Saccharomyces cerevisiae MNJ3 (pMNJ1)
Coulibaly
Adama1, Séa Téhi Bernard2, Bla Kouakou
Brice1, Yapi Houphouët Félix1 and
Djaman Allico Joseph1,3*
1Laboratoire
de Pharmacodynamie-Biochimie, UFR Biosciences, Université de
Cocody, 22 BP582 Abidjan 22
2Laboratoire
de Biotechnologie, UFR Biosciences, Université de Cocody, 22
BP582 Abidjan 22.
3Département
de Biochimie clinique & fodamentale, Institut Pasteur de
Côte d’Ivoire, 01 BP 490 Abidjan 01.
*Corresponding
author. E-mail:
djamanj@yahoo.fr. Tél : 225 22-48-10-00 poste 6807.
Accepted 2 June, 2008 |
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Growth conditions which maintains DHOase overproduction by
Saccharomyces cerevisiae MNJ3 (pMNJ1) and allow
sufficient biomass production to ensure DHoase’s
purification were investigated. We used as basal medium the
Yeast Carbon Base (YCB; Difco), especially designed for
studies of nitrogen metabolism in yeasts. Thus the effects
of an additional carbon source (glucose or citric acid) and
the influence of the nitrogen source (asparagine or ammonium
sulphate) as well as that of pH on growth of this strain
were studied by supplementing the Yeast Carbon Base medium (Difco)
with the above components. Cells were collected and DH0ase
activity was determined. This study showed that the best
conditions for biomass production required supplementation
of YCB with asparagines 5 g/l, glucose 20 g/l at pH 5.5 (M12
medium). In this medium DHOase activity decrease with time;
thus in terms of DHOase yield, the best time for havesting
cells is reached after 30 to 38 h of growth.
Key words:
Biomass production, dihydroorotase, optimization,
Saccharomyces cerevisiae. |
