Solid State Fermentation Based Olive Pomace Using Streptomyces Strains: A Preliminary Study

This study represents a preliminary investigation aimed to assess the possibility to recycle and
valorize olive pomace by solid state fermentation (SSF) using Streptomyces strains. The olive
pomace was collected from an olive pressing factory (super press system) during the olive fruit
pressing season. The study was carried out at IMBE, University Aix Marseille-France, between April
2013 and June 2013 and at LMA, University of Bejaia-Algeria in September 2013. Three
Streptomyces strains designated S1M3I, S1M3II and S1M3III were cultured on solid state
fermentation based olive pomace at 30°C for 10 days, and subsequently, the lignocellulolytic enzyme
activities (xylanase, CMCase and laccase), the viability of the microorganisms and the pH of the
resulting substrates, were determined. The fermented substrate pH values remained significantly
stable (p ˂ 0.05) throughout the fermentation period for the three strains; they were fluctuated
between 6.54 and 6.99. The viability of all Streptomyces strains studied, decreased significantly (p ˂
0.05) during the first four days of incubation, to reach up 0 cfu/mL of viability and 0 U/g enzymatic
activities (xylanase, CMCase and laccase activities) were recorded for the three strains. Streptomyces
strains, under the experimental conditions (30°C, pH 7 and 75% of moisture), were unable to grow
and produce lignocellulolytic enzymes in solid state fermentation based olive pomace due to the
mycelial morphology and Streptomyces developmental cycle, no neglect, the environmental factors.
These preliminary results suggest that SSF – Streptomyces system is not suitable for conversion of
solid waste from olive processing industry and to produce lignocellulolytic enzymes.