Rheological and morphological characterization of Streptomyces olindensis growing in batch and fed-batch fermentations

Abstract

Mathematical correlations between rheological properties of the fermentation broth (consistency index, K, and flow behavior index, n), biomass concentration (X) and average clump dimension (D) of Streptomyces olindensis in bioreactor cultivations were obtained, during batch and fed-batch processes. Two types of correlations were compared: the first considered the influence of only biomass concentration (X) on rheological properties (K and n), the second considered the influence of both biomass concentration (X) and morphology (average clump dimension, D) on rheological properties. Clump dimension was assessed by image analysis. Clumps were shown to be the major morphological class during all runs. Incorporation of the morphological parameter in the model improved the capacity to predict the experimental values of the consistency index (K).