Fungal treatment of corn processing wastewater in an attached growth system

Abstract

Corn processing wastewater was treated in an attached growth system of Rhizopus oligosporus fungi. The effects of hydraulic retention time (HRT) and plant-based components in the support media were evaluated in 1 L reactors under non-aseptic conditions. Plastic composite support (PCS) tubes, composed of 50% (w/w) polypropylene (PP) and 50% (w/w) agricultural products were used as support media or, as a test, PP only. A maximum chemical oxygen demand (COD) removal of 78% was achieved at a 5 h HRT with a biomass yield of 0.44 gVSS/gCODremoved. The biomass yield increased to 0.48 gVSS/gCODremoved while COD removal reduced to 70% at a 2.5 h HRT. Competitive bacterial growth was reduced at the shorter HRT. A lower HRT of 1.25 h led to biomass wash out from the reactor. Significantly lower COD removal of 28% and biomass yield of 0.19 gVSS/gCODremoved were observed in a biofilm reactor with PP tubes alone, indicating that the agricultural components in PCS media were essential for better biofilm formation and organic removal.

Fungal Treatment of Crop Processing Wastewaters with Value-Added Co-Products

“…As pH increased, the number of opportunistic bacteria under non-aseptic conditions increased from 1 9 10 6 to 30 9 10 6 colony-forming units (CFU)/ml. Similar results were also reported by Jasti et al [42] while using R. oligosporus to treat wet corn-milling wastewater. The bacterial biomass concentration was found to be greater at a pH of 4.5 than at pH of 4.0.…”

“…Jasti et al [42] operated an attached growth bioreactor with plastic composite support (PCS) tubes, with and without the addition of nutrients (ammonium bicarbonate and potassium hydrogen phosphate) for treating wet-milling corn processing wastewater. The results indicated that although the addition of nutrients improved COD removal rates and observed yields, it did not affect fungal protein production to a great extent.…”

“…Under aseptic conditions in a nutrient medium, R. oligosporus was reported to produce a 3% yield of chitosan [71], as well as 4 and 40% yields of lysine and protein, respectively [72]. R. oligosporus was successfully cultivated on wheat milling and corn wet-milling streams, achieving significant reductions in COD of up to 80-90% [6,7,9,39,42,45,49,53,73,[74][75][76][77][78][79][80]. The filamentous nature of fungal mycelia and potential for pellet formation aid in the recovery of fungal biomass [9,14].…”

Remoção de macronutrientes de efluente da indústria de castanha de caju por uso de reator aeróbio em batelada com inóculo fúngico

“…Os fungos podem iniciar a degradação de poluentes que não são capazes de serem utilizados pelas bactérias, porém, a completa remoção da matéria orgânica presente no meio é completada pela ação de bactérias (BAILEY; SMITH; BOLTON JR, 2002;JASTI et al, 2006;HAI et al, 2008). Deste modo, as potentes enzimas fúngicas, como lacases, peroxidases, fenoloxidases, entre muitas outras, são arsenal importantíssimo a ser utilizado no processo de biorremediação (SANGHI; DIXIT; VERMA, 2010).…”

Suitability of Membrane Bioreactor for treatment of recalcitrant textile dye wastewater utilising white-rot fungi

“…TOC was measured with a Total Organic Carbon analyzer (TOC-V, Shimadzu, Japan). The mixed liquor suspended solids (MLSS) concentration was measured according to the standard methods (APHA/AWWA/WEF, 1998).The relative abundance of fungi/bacteria in MLSS was estimated following the method of Jasti et al(2006) using 20 times diluted samples. Transmembrane pressure (TMP), as an indicator of membrane fouling, was continuously monitored using a vacuum pressure gauge (GC 61, Nagano keiki Co. Ltd., Japan).…”