title: Use of organic waste for the production of added-value holocellulases with Cellulomonas flavigena PR-22 and Trichoderma reesei MCG 80.
abstract: We evaluated the production of holocellulases from the cellulolytic microorganisms Cellulomonas flavigena PR-22 and Trichoderma reesei MCG 80 using as substrates the organic fraction of municipal solid waste (OFMSW) and digestates from a hydrogenogenic-methanogenic bioenergy production process. The first set of experiments (E1) used the mutant actinobacteria C. flavigena PR-22 whereas another set (E2) used the mutant filamentous fungi T. reesei MCG 80. In E1 with OFMSW as substrate, xylanolytic activities ranged from 1800 to 3900 international units g(holocellulose)(-1) (IU g(hol)(-1)), whereas the cellulolytic activities ranged from 220 to 420 IU g(hol)(-1). The variation of agitation speed did not have a significant effect on enzyme activity, whereas the increase of substrate concentration had a significant negative effect on both xylanolytic and cellulolytic activities on a holocellulose feed basis. Regarding E2, the OFMSW was evaluated at 1, 2 and 3 % volatile solids (VS). At 2 % VS the best filter paper activities were 1200 filter paper units (FPU) l(-1); however, in a holocellulase basis the best result was 67 FPU g(hol)(-1), corresponding to 1 % VS. Next, OFMSW was compared with OFMSW supplemented with lactose, digested solids from hydrogenogenic fermentation (D1) and digested solids from a two-stage process (D2). Against expectations, no positive effect was found in OFMSW due to lactose. The best enzymatic titres were in the order D1 > OFMSW ≈ OFMSW + lactose > D2. The use of digestates from hydrogenogenic fermentation for enzyme production holds promise for waste management. It promotes energy and added-value bioproduct generation-a green alternative to common practice of management and disposal of organic wastes.
authors.affiliation: Department of Biotechnology and Bioengineering, Centro de Investigación y de Estudios Avanzados del IPN, Mexico DF, México.
authors.forename: Carlos
authors.initials: C
authors.lastname: Escamilla-Alvarado
authors.forename: Héctor M
authors.initials: HM
authors.lastname: Poggi-Varaldo
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Ponce-Noyola
mesh_terms: D002480:Cellulase / Q000378:metabolism*; D040143:Cellulomonas / Q000201:enzymology*; D005285:Fermentation; D014242:Trichoderma / Q000201:enzymology*
chemical_list: D002480:Cellulase
keywords: Biorefinery; Cellulomonas flavigena; Trichoderma reesei; cellulases; digestates; organic waste; xylanases