title: Evaluation of the Fermentation Potential of Pulp Mill Residue to Produce D(-)-Lactic Acid by Separate Hydrolysis and Fermentation Using Lactobacillus coryniformis subsp. torquens.
abstract: Lactic acid is widely used in chemical, pharmaceutical, cosmetic, and food industries, besides it is the building block to produce polylactic acid, which is a sustainable alternative biopolymer to synthetic plastic due to its biodegradability. Aiming at producing an optically pure isomer, the present work evaluated the potential of pulp mill residue as feedstock to produce D(-)-lactic acid by a strain of the bacterium Lactobacillus coryniformis subsp. torquens using separate hydrolysis and fermentation process. Enzymatic hydrolysis, optimized through response surface methodology for 1 g:4 mL solid/liquid ratio and 24.8 FPU/gcelluloseenzyme loading, resulted in 140 g L-1total reducing sugar and 110 g L-1glucose after 48 h, leading to 61 % of efficiency. In instrumented bioreactor, 57 g L-1of D(-)-lactic acid was achieved in 20 h of fermentation, while only 0.5 g L-1of L(+)-lactic acid was generated. Furthermore, product yield of 0.97 g/g and volumetric productivity of 2.8 g L-1h-1were obtained.
authors.affiliation: Departamento de Engenharia Química e Petróleo, Universidade Federal Fluminense, Rua Passo da Pátria, 156-Campus da Praia Vermelha, São Domingos, Niterói, RJ, 24210-310, Brazil.
authors.forename: Anelize
authors.initials: A
authors.lastname: de Oliveira Moraes
authors.affiliation: Departamento de Engenharia Química e Petróleo, Universidade Federal Fluminense, Rua Passo da Pátria, 156-Campus da Praia Vermelha, São Domingos, Niterói, RJ, 24210-310, Brazil.
authors.forename: Ninoska Isabel Bojorge
authors.initials: NI
authors.lastname: Ramirez
authors.affiliation: Centro de Tecnologia, Escola de Química, Departamento de Engenharia Bioquímica, Universidade Federal do Rio de Janeiro, Avenida Athos da Silveira Ramos, 149-Cidade Universitária, Rio de Janeiro, RJ, 21941-909, Brazil. nei@eq.ufrj.br.
authors.forename: Nei
authors.initials: N
authors.lastname: Pereira
mesh_terms: D004798:Enzymes / Q000378:metabolism; D005285:Fermentation; D006868:Hydrolysis; D007220:Industrial Waste; D007700:Kinetics; D019344:Lactic Acid / Q000378:metabolism*; D007778:Lactobacillus / Q000378:metabolism*; D010209:Paper
chemical_list: D004798:Enzymes; D007220:Industrial Waste; D019344:Lactic Acid
keywords: D(−)-lactic acid; Enzymatic hydrolysis; Lactobacillus coryniformis subsp. torquens; Pulp mill residue; Separate hydrolysis and fermentation