ETUDE CINETIQUE DE LA CROISSANCE DE Saccharothrix algeriensis DSM 44581 EN FERMENTEUR BATCH EN PRESENCE D’ACIDEpdfBENZOÏQUE ET D’ACIDE HUMIQUE

Abstract

This work aimed to investigate the effect of benzoic acid and humic acid on the growth of Saccharothrix algeriensis DSM 44581 on semi-synthetic medium by using controlled batch fermentors. The maximum biomass values were 6.54, 8.54 and 7.32 g/l for the control and in the presence of benzoic acid and humic acid, respectively. After 48 hours of fermentation, the control culture showed a noticeable cell lysis than those containing the benzoic and humic acids. A slight acidification of the culture medium was observed in the presence of benzoic acid compared to two other cultures (humic acid and control). On the other hand, we observed a rapid consumption of O2 during the first 24 hours of fermentation in the presence of benzoic acid and in the control medium. The amounts of total and mineral nitrogen decreased slowly in all cultures during the first 80 hours of fermentation. The amount of mineral nitrogen was zero starting from 144 hours of fermentation for the control and also in the presence of benzoic acid. The growth rate of S. algeriensis in all fermentations was fast during the first 10 h of fermentation. The control culture showed a partially cell lysis in comparison to cultures with organic acids. This result showing that these organic acids could be used for biomass maintaining. The formation of biomass was influenced by the addition of organic acids. The experiment in the fermentor showed some differences with results obtained in Erlenmeyers.