Evaluation of Potential Fungal Species for the in situ Simultaneous Saccharification and Fermentation (SSF) of Cellulosic Material

Three fungal species were evaluated for their abilities to saccharify pure cellulose. The three species chosen represented three major wood-rot molds; brown rot (Gloeophyllum trabeum), white rot (Phanerochaete chrysosporium) and soft rot (Trichoderma reesei). After solid state fermentation of the fungi on the filter paper for four days, the saccharified cellulose was then fermented to ethanol by using Saccharomyces cerevisiae. The efficiency of the fungal species in saccharifying the filter paper was compared against a low dose (25 FPU/g cellulose) of a commercial cellulase. Total sugar, cellobiose and glucose were monitored during the fermentation period, along with ethanol, acetic acid and lactic acid. Results indicated that the most efficient fungal species in saccharifying the filter paper was T. reesei with 5.13 g/100 g filter paper of ethanol being produced at days 5, followed by P. chrysosporium at 1.79 g/100 g filter paper. No ethanol was detected for the filter paper treated with G. trabeum throughout the five day fermentation stage. Acetic acid was only produced in the sample treated with T. reesei and the commercial enzyme, with concentration 0.95 and 2.57 g/100 g filter paper, respectively at day 5. Lactic acid production was not detected for all the fungal treated filter paper after day 5. Our study indicated that there is potential in utilizing in situ enzymatic saccharification of biomass by using T. reesei and P. chrysosporium that may lead to an economical simultaneous saccharification and fermentation process for the production of fuel ethanol

Characterization and improvement of oxygen transfer in pilot plant external air-lift bioreactor for mycelial biomass production

The oxygen transfer dynamics in a pilot plant external air-lift bioreactor (EALB) during the cultivation of mycelial biomass were characterized with respect to hydrodynamic parameters of gas holdup (ε), oxygen transfer coefficient (KLa) and superficial gas velocity (U g), and dissolved oxygen (DO). An increased flow rate of air supply was required to meet the increased oxygen demand with mycelial biomass growth. Consequently, an increase in air flow rate led to an increase in ε, KLa and the DO level. The enhancement of oxygen transfer rate in the cultivated broth system, however, was limited with highly increased viscosity of the mycelial broth. An increase in air flow rate from 1.25 to 2.00 v/v/m resulted in a low increment of oxygen transfer. The newly designed pilot plant EALB with two air spargers significantly improved processing reliability, aeration rate and KLa. The pilot plant EALB process, operated under a top pressure from 0 to 1.0 bars, also demonstrated a significant improvement of oxygenation efficiency by more than 20% in DO and KLa. The performance of the two sparger EALB process under top pressure demonstrated an efficient and economical aerobic system with fast mycelial growth and high biomass productivity in mycelial biomass production and wastewater treatment

Sustainable Pyrolytic Production of Zerovalent Iron

Pyrolysis of biorenewable feedstocks and iron oxides is potentially a greener and more sustainable pathway to producing zerovalent iron (ZVI) for environmental rehabilitation. The resulting biochar-zerovalent iron (BC-ZVI) also shows improved remediation kinetics of trichloroethylene over conventional ZVI. Understanding the transformations of iron to ZVI and the influence of feedstock chemistry on ZVI is critical to the production of BC-ZVI and has not been reported previously. BC-ZVI production was studied by one-step pyrolysis of cellulose, corn stover, dried distillers’ grain, red oak, and switchgrass pretreated with FeCl3. Pyrolysis at 900 °C effectively reduced Fe to ZVI with most feedstocks; however, the association of silicon (Si) and phosphorus (P) with Fe resulted in formation of fayalite and Fe phosphates and phosphides, which limited ZVI production efficiency and/or facilitated corrosion of ZVI. Dispersion of ZVI phases on biochar surfaces and association with Si facilitated oxidation of ZVI due to greater accessibility to oxygen and enhanced corrodibility of ZVI in association with fayalite. Feedstocks low in Si and P such as cellulose and red oak yield BC-ZVI suitable for environmental applications

Purification of thin stillage from dry-grind corn milling with fungi

The present invention is directed to an improved method of processing thin stillage from ethanol production and/or other industrial processes to produce high value fungal biomass that can be recovered by simple means. The effluent is sanitized and recycled using a novel disinfection technique. This innovative approach generates revenue from low value thin stillage, while reducing wastewater purification costs

Enzyme Production by Wood-Rot and Soft-Rot Fungi Cultivated on Corn Fiber Followed by Simultaneous Saccharification and Fermentation

This research aims at developing a biorefinery platform to convert lignocellulosic corn fiber into fermentable sugars at a moderate temperature (37 °C) with minimal use of chemicals. White-rot (Phanerochaete chrysosporium), brown-rot (Gloeophyllum trabeum), and soft-rot (Trichoderma reesei) fungi were used for in situ enzyme production to hydrolyze cellulosic and hemicellulosic components of corn fiber into fermentable sugars. Solid-substrate fermentation of corn fiber by either white- or brown-rot fungi followed by simultaneous saccharification and fermentation (SSF) with coculture of Saccharomyces cerevisiae has shown a possibility of enhancing wood rot saccharification of corn fiber for ethanol fermentation. The laboratory-scale fungal saccharification and fermentation process incorporated in situ cellulolytic enzyme induction, which enhanced overall enzymatic hydrolysis of hemi/cellulose components of corn fiber into simple sugars (mono-, di-, and trisaccharides). The yeast fermentation of the hydrolyzate yielded 7.8, 8.6, and 4.9 g ethanol per 100 g corn fiber when saccharified with the white-, brown-, and soft-rot fungi, respectively. The highest ethanol yield (8.6 g ethanol per 100 g initial corn fiber) is equivalent to 35% of the theoretical ethanol yield from starch and cellulose in corn fiber. This research has significant commercial potential to increase net ethanol production per bushel of corn through the utilization of corn fiber. There is also a great research opportunity to evaluate the remaining biomass residue (enriched with fungal protein) as animal feed

Ozone retention method and system

A method and system of ozone treatment diverts a portion of water from a flow of water in a conduit, injects ozone into the portion to provide an ozonated portion, and recombines the ozonated portion with the flow of water in the conduit. Another method and system identifies a species-destructive reaction product of ozone with a water constituent, determines a life of the reaction product, and contacts ozone with a water containing the species for a period determined according to the determined life of the reaction product

Processes for isolating chitin and chitosan from fungal biomass

Methods of extracting chitin and chitosan from fungal biomass using a solution of one or more ammonia compounds, amines, and/or alkaline silicate compounds. The solution dissolves and extracts amino acids, fatty acids and other carbohydrates from the fungal cells leaving chitin and/or chitosan, and the extractant may be recovered from the liquid by simple phase changes such as heating or cooling, dissociation into volatile components, distillation and/or solidification and separation of immiscible extractants. Further lipid removal may be achieved with one or more organic solvents, which may also be recovered by distillation

Controlled bypass flow and ozone proportion method and system

A method and system of ozone treatment diverts a portion of water from a flowof water in a conduit; injects an ozone-containing gas into the portion to provide an ozonated portion; recombines the ozonated portion with the flow of water in the conduit; and controls and regulates the diverted portion to provide a minimum diverted portion flow rate according to flow in the conduit andproportion of ozone in the injected gas

Bypass flow and ozone proportion method and system

A method and system of ozone treatment diverts a portion of water from a flow of water in a conduit; injects an ozone-containing gas into the portion to provide an ozonated portion; recombines the ozonated portion with the flow of water in the conduit; and regulates the diverted portion to provide a minimum diverted portion flow rate according to flow in the conduit and proportion of ozone in the injected gas

Evaluation of Rhizopus oligosporus Yeast Supplementation on Growth Performance and Nutrient Digestibility in Nursery Pigs

The growth and performance of 24 nursery pigs fed a fungal cultivation of Rhizopus oligosporus (RO) was evaluated in a 28-day feeding and digestibility study. Nursery pigs average start weight of 5.62 ± 0.35 kg were provided ad libitum access to a corn-soybean diets containing three levels of RO, 0, 10, or 20%. Diets were formulated to be isocaloric and isolysinic, and contained the digestibility marker titanium dioxide. There was no difference in pig performance based on dietary inclusion of RO fungus. However, total tract DE was improved when feeding RO. Altogether, these data indicate that Rhizopus oligosporus cultivated on distillers stillage and bioproducts can be used in nursery swine diets with no negative effects on performance