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PRODUCTION OF FUEL ALCOHOLS BY FERMENTATIONS . PHYSIOLOGICAL BASIS FOR IMPROVING THE PROCESS

Objective



A FLOCCULATION BIOREACTOR WAS DESIGNED AND CONSTRUCTED BY THE AUTHORS. THE MATERIAL USED WAS GLASS (CHEAP AND EASY TO STERILIZE AND REPLACE). IN ORDER TO TEST THE FLOCCULATION EFFICIENCY OF THIS SYSTEM A NON-FLOCCULENT STRAIN OF KLUYVEROMYCES MARXIANUS WAS INOCULATED IN THE CULTURE MEDIUM, WHICH CONSISTED OF LACTOSE (50 G/L); YEAST EXTRACT (1 G/L) AND SIMPLE MINERAL SALTS. THE PH WAS CONSTANTLY REGULATED AT 4.2. THE DILUTION RATE WAS SLIGHTLY INCREASED EVERYTIME AT STAT STATIONNARY STATE WAS REACHED.
ONE MONTH AFTER THE BEGINNING OF THE CONTINUOUS FERMENTATION THE BIOMASS CONCENTRATION INSIDE THE FERMENTOR REACHED 28 G/L (DRY WEIGHT/L) WHILE THE EFFLUENT WAS ALMOST CLEAR WITH A BIOMASS CONCENTRATION OF LESS THAN 0.2 G/L, AT A DILUTION RATE OD D=0.2 H TO THE POWER OF MINUS 1. THE HELM'S SEDIMENTATION TEST MADE AT THE END OF EACH FERMENTATION SHOWED THAT AFTER 3 MINUTES PRATICALLY ALL THE BIOMASS OF THE STRAIN ISSUED FROM THE EXPERIMENT HAD SEDIMENTED, WHILE THE MOTHER STRAIN REMAINED IN SUSPENSION.
IT MAY THEN BE CONCLUDED THAT THE CONTINUOUS FERMENTATION SYSTEM IS SUITABLE AS A FLOCCULATION BIOREACTOR AND CAN BE USED FOR THE ISOLATION OF FLOCCULENT STRAINS.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

Instituto Nacional de Investigação Científica
Address
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