TY - CHAP

T1 - Bioconversion of agri-food residues into lactic acid

AU - Venus, Joachim

AU - Pleißner, Daniel

PY - 2016/9/29

Y1 - 2016/9/29

N2 - Introduction: Especially for biotechnological processes, in which the carbon of various substrates should be converted into microbial products, there is an increasing interest in the use of cheap raw materials, biogenic residues and wastes. Aims: The goal is to develop a lactic acid fermentation process based on the substitution of expensive substrates and nutrients by cheaper materials from biomass due to their main proportion of the whole costs. Materials and Methods: Many feedstocks cannot be used normally for fermentation directly because the fermentable sugars are bound in the structure especially as cellulose and several types of hemicelluloses. A pre-treatment of agricultural residues is required when enzymes are used for hydrolysis in an enzymatic approach. The pre-treatment in form of an acidic pre-digestion or physicochemical treatment (e. g. steam explosion) ensures that the recalcitrant structure is accessible to enzymes [Ravindran/Jaiswal, 2016]. Results: The viability of the production of lactic acid from several residues has been demonstrated from laboratory up to pilot scale including the entire value chain starting from the raw material and resulting with a polymer-grade product (LA). Pre-treatment methods are energy-intensive and the selection of an efficient method is crucial for the overall economy of a biotechnological process. As a result of the achievements so far the optimization of pre-treatment, hydrolysis, fermentation, and downstream processing steps in parallel together with the screening of other LA producing bacteria have been performed [Pleissner/Venus, 2014]. Conclusion: The entire processing chain has been implemented to generate marketable lactic acid of high enantiopurity and quality. Exploitation of L(+)- and D(-) lactic acid for the production of biopolymers is one of the recent applications. It is likely that one of the future trends in lactic acid production will end up in mixtures of different low-cost raw materials in order to avoid the use of expensive complex supplements [Koutinas et al., 2014].

AB - Introduction: Especially for biotechnological processes, in which the carbon of various substrates should be converted into microbial products, there is an increasing interest in the use of cheap raw materials, biogenic residues and wastes. Aims: The goal is to develop a lactic acid fermentation process based on the substitution of expensive substrates and nutrients by cheaper materials from biomass due to their main proportion of the whole costs. Materials and Methods: Many feedstocks cannot be used normally for fermentation directly because the fermentable sugars are bound in the structure especially as cellulose and several types of hemicelluloses. A pre-treatment of agricultural residues is required when enzymes are used for hydrolysis in an enzymatic approach. The pre-treatment in form of an acidic pre-digestion or physicochemical treatment (e. g. steam explosion) ensures that the recalcitrant structure is accessible to enzymes [Ravindran/Jaiswal, 2016]. Results: The viability of the production of lactic acid from several residues has been demonstrated from laboratory up to pilot scale including the entire value chain starting from the raw material and resulting with a polymer-grade product (LA). Pre-treatment methods are energy-intensive and the selection of an efficient method is crucial for the overall economy of a biotechnological process. As a result of the achievements so far the optimization of pre-treatment, hydrolysis, fermentation, and downstream processing steps in parallel together with the screening of other LA producing bacteria have been performed [Pleissner/Venus, 2014]. Conclusion: The entire processing chain has been implemented to generate marketable lactic acid of high enantiopurity and quality. Exploitation of L(+)- and D(-) lactic acid for the production of biopolymers is one of the recent applications. It is likely that one of the future trends in lactic acid production will end up in mixtures of different low-cost raw materials in order to avoid the use of expensive complex supplements [Koutinas et al., 2014].

KW - Chemistry

M3 - Published abstract in conference proceedings

T3 - University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca

SP - 125

BT - The 15th International Symposium Prospects for me

A2 - Vondnar, Dan C.

PB - University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca

CY - Cluj-Napoca, Rumänien

ER -