This Small Business Innovation Research Phase I project describes a simple, novel and economical process for converting lignocellulosic feedstocks, such as wheat straw, to lipids for conversion to biodiesel and fatty acids for specialty markets (e.g. wax esters, stearic/oleic acids) using a minimal number of steps compared to current technologies. The innovative technology described here is based on the use of a novel microorganism isolated from Yellowstone National Park, which is able to withstand extreme acidic conditions and is capable of efficiently degrading cellulose, lignin and hemicellulose. The organism produces high concentrations of lipids (30-60% of cell volume) in a one-step process when grown aerobically on waste feedstocks in minimal dilute acid medium. The primary objective of this SBIR Phase I is to determine the feasibility of lipid production from various lignocellulosic substrates and determine fatty acid profiles for biofuel production under laboratory scale systems. Additionally, high value commercial products will be evaluated including waxes, biolubricants, and nutraceuticals. Preliminary lab bench studies have shown conversion of wheat straw to lipids ideal for biodiesel at 80g lipid/kg dry weight and the goal of this study is to produce 110 lipids/kg, which cost analysis studies indicate would be competitive with fossil fuels.
The broader impact/commercial potential of this project includes the potential for a low cost, simple and effective means for lipids (biofuel precursors) from abundant lignocellulosic substrates. The products produced by the proposed innovative process includes biodiesel, fatty acids for specialty markets, enzymes for biofuel production, and raw material for wood product substitutes and fuel pellets. These products will be sold to biodiesel producers and distributors, petrochemical companies, composite material manufacturers, and fuel pellet manufacturers. Only a few companies and research groups are investigating microbial biodiesel production directly from lignocellulosic waste and, therefore, the scientific community will benefit from this research through a better understanding of direct degradation of lignocellulose materials and production of lipids by microorganisms. Furthermore, research into the growth and metabolisms of the novel microorganism described here will be directly beneficial to researchers studying other lipid producing strains. The success of this one-step technology would have a significant economic impact for the nation by providing a novel route to the production biofuels and biomass based industrial products from renewable sources.
Sustainable Bioproducts (SB) has developed a breakthrough low cost, simple, and scalable microbial process for conversion of lignocellosic feedstocks (e.g. wheat straw and corn stover) to oils, which may subsequently be sold for production of biodiesel, lubricants, cosmetics, pharmaceutical products, and neutraceuticals. Our process is based on a highly novel fungal strain obtained from Yellowstone National Park (strain MK7) that is capable of converting waste feedstocks to oils at significantly higher yields and rates compared to other studied microorganisms. Importantly, the oil is relatively easy to extract compared to other oil-producing microorganisms (e.g. algae). Our process produces 46 gallons of extractable oils per tonne of waste feedstock. About 5% of our oil is comprised of high-value fatty acids not found in most vegetable oils (e.g. omega-7 oils), which are ideal for specialty markets (e.g. neutraceuticals, cosmetics and pharmaceutical products). Current market trends indicate that our oils will be highly profitable when sold for biodiesel (2013 average market price of $4.20/gallon) as our oil costs approximately $2.70 per gallon to produce and will benefit from a $1.01 per gallon federal biodiesel tax subsidy. SB will continue to analyze the market for highest value applications, especially for our high-value omega-7 fatty acids (e.g. neutraceutical, cosmetic and pharmaceutical products). Our research revealed that under optimized conditions, strain MK7 converts a wide variety of lignocellulosic feedstocks to oils with greater efficiency and at higher rates than any other microbial process to our knowledge. These high rates are, in-part, attributed to the fact that strain MK7 uses a full suite of potent enzymes to degrade feedstocks and convert them to lipids. Conversion yields as high as 150 g extractable lipid/1000 g dry feedstock (switchgrass, wheat straw and yard leaves) were achieved under optimal conditions. Lipids are easily extracted with chloroform:methanol without the need for cell disruption (e.g. bead beating). The addition of strain MK9, another organism isolated by Sustainable Bioproducts, increased lipid yields by 25% and significantly increased lipid production rates from 11-14 days of cultivation with strain MK7 to only 6 days with the strain MK7/MK9 co-culture. Lipid yields equate to approximately 46 gallons of lipids per metric ton of waste feedstocks (i.e. wheat straw, corn stover and municipal solid waste). NSF funding for this grant enabled us to show that strain MK7 is capable of producing easily extractable lipids from waste feedstocks at yields and rates that are commercially viable. Because of this and many other advantages of strain MK7, we envision that our technology will be game changing for the biofuels industry and that the financial benefits will be a strong impetus for wide spread application.
