title: Ammonium carboxylate production from sugarcane trash using long-term air-lime pretreatment followed by mixed-culture fermentation.
abstract: Sugarcane trash (ST) was converted to ammonium carboxylates using a novel bioprocessing strategy known as long-term air-lime pretreatment/mixed-culture fermentation. At mild conditions (50°C, 5 weeks, 1-atm air, and excess lime loading of 0.4 g Ca(OH)(2)/(g dry biomass)), air-lime pretreatment of ST had moderate delignification (64.4%) with little loss in polysaccharides. Without employing detoxification, sterility, expensive nutrients, or costly enzymes, the feedstock (80% treated ST/20% chicken manure) was fermented to primarily ammonium acetate (>75%) and butyrate by a mixed culture of marine microorganisms at 55°C. In the best four-stage countercurrent fermentation, the product yield was 0.36 g total acids/(g VS fed) and the substrate conversion was 64%. Model predictions indicate both high acid concentrations (>47.5 g/L) and high substrate conversions (>70%) are possible at industrial scale.
authors.affiliation: Department of Chemical Engineering, 3122 TAMU, Texas A&M University, College Station, TX 77843-3122, USA.
authors.forename: Balasubramaniyan
authors.initials: B
authors.lastname: Nachiappan
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Fu
authors.forename: Mark T
authors.initials: MT
authors.lastname: Holtzapple
mesh_terms: D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D017610:Calcium Compounds; D005285:Fermentation / Q000502:physiology*; D008956:Models, Chemical; D010087:Oxides; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012037:Refuse Disposal / Q000379:methods*; D031786:Saccharum / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; D000644:Quaternary Ammonium Compounds; C016538:lime