Location: Renewable Product Technology Research
2019 Annual Report
Objectives
This project creates new chemical and biochemical processes to produce value-added products from biomass, particularly from plant lipids and lignocellulose. The new, bio-based value-added products will create new markets and expand existing markets for vegetable oils and agrimaterials, enhancing the profitability of small- and medium-sized agribusinesses, which in turn benefits the local rural economy. New products will be developed that improve the health and safety of the American public, extend the shelf life of consumer products, and provide biobased alternatives and substitutes for petroleum-based chemicals. We will collaborate within the project, with other Agricultural Research Service researchers, with academic researchers and industrial partners to reach the following objectives.
Objective 1: Enable, from a technological perspective, commercially-viable microbial, enzymatic, and chemical processes to produce commercial products from vegetable oils. Subobjective 1.A: Evaluate marketable oil derivatives under conditions of use. Subobjective 1.B: Produce polyol oils and oxygenated fatty acids from soybean oil through novel microbial biocatalysis.
Objective 2: Enable new commercial encapsulation systems for controlled-release of bioactive molecules.
Objective 3: Enable new commercial processes for the production of industrial chemicals from vegetable oils or lignocellulosics.
Approach
The objectives of this research are accomplished using strategies that include isolated enzymes in unconventional media, microbial strain development and fermentation, encapsulation and controlled release of bioactive molecules, high temperature, inorganic catalytic conversions, chemical/biochemical syntheses, and analytical analyses using state of the art equipment and facilities. Approaches for this project currently include the following areas of research:
Vegetable oil-based biochemicals. We develop chemical and biochemical systems for the conversion of seed oils to value-added specialty/commodity chemicals. Our approach is to use isolated enzymes, whole microorganisms, and inorganic catalysts to modify domestically produced vegetable oils to introduce functional features valuable to consumer marketplaces. While the industry accepts such new molecules upon adequate safety testing, stronger product claims based on efficacy still need to be substantiated. Biochemical, cellular, and tribological analyses are undertaken to establish the metabolic fate and influence of the novel vegetable oil derivatives. No human or live animal testing is needed.
Encapsulation and timed release of bioactive molecules. We develop phospholipid-based encapsulation systems (i.e. liposomes) that limit the release of bioactive molecules and protect the bioactives from degradation. Liposomes are used to encapsulate the bioactives of interest and the bioactives-loaded liposomes are further compartmentalized within a secondary liposome for increased protection. The multicompartmentalized liposome system provides increased protection and controlled release of the bioactive molecule. The liposome encapsulated bioactive systems are analyzed for stability and release rate of the bioactive molecules. Highly stable encapsulation and controlled release systems are highly desirable in the functional foods and beverage industries.
Integrated biorefinery systems for biochemicals. We couple biomass pretreatment with catalytic conversions to form integrated processes to convert lignocellulosics and lipids into bio-based chemicals that replace petroleum-based products. Whole biomass, crop residue or dedicated crops (e.g. switchgrass), is milled and extracted with hot water to produce a mixture of lignin and sugars. Lipids are treated to introduce oxygen atoms into the fatty acids. These pretreated materials are subjected to catalytic conversion to produce bio-based chemicals. The catalysts are designed and synthesized with specific capabilities to produce targeted agri-based chemicals. The pretreatment and catalytic conversion steps are developed to demonstrate the technical feasibility of a continuous pretreatment/catalytic conversion technology platform for use in biorefineries.
Progress Report
Progress was made on the three project objectives, all of which fall under National Program 306, Component 2, Quality and Utilization of Agricultural Products: Non-Food. Progress made on Objective 1 and Objective 3 contributed to solving Problem 2.B, enabling technologies to produce new and expanded marketable nonfood, nonfuel bioproducts from agricultural products and byproducts. The progress made on Objective 2 this year focused on Problem 2.B and contributed to solving Problem 1.B, by developing new protective encapsulation and delivery systems derived from agricultural products and byproducts.
Under Objective 1, significant progress was made in evaluating the efficacy and fungibility of ARS patented soy-based active ingredients compared to industry standards under conditions of use. For increased market penetration and adoption of use by industry partners and end users, ARS scientists developed methods to quantify the photostability and photoprotective effects of their soy-based active ingredients. The natural antioxidants, Vitamins E and C, often used in topical formulations to protect skin from oxidative stresses, degrade when exposed to ultraviolet (UV) radiation (sun light). Progress was made to demonstrate that the soy-based active ingredients have UV properties that protect Vitamin C and E from UV degradation as well as or better than commercially used, petroleum-based active ingredients. Results from this research are essential for end user evaluation of our soy-based ingredients for use in their personal care and health and beauty aid products. Related to Objective 2, efforts were begun to micro encapsulate the soy-based active ingredient oils in starch-pectin matrices. This will allow for the expanded use of the soy-based active ingredients in aqueous, thin film, and color fastness applications.
Under Objective 2, progress was made in developing two different encapsulation methods that use sugar-based polymers discovered by ARS researchers to form nanoemulsions (microscopic emulsions with the polymer and bioactive compounds). These techniques use high-pressure homogenization with either a water-insoluble polymer made using microbial enzymes or a water-soluble polymer isolated from a local species of frost grape vines. The water-insoluble sugar polymer was shown to form nanoparticle that are extremely stable, despite having characteristics that suggest it should clump together and fall out of solution. This polymer also appears to readily encapsulate one of our ultraviolet-absorbing soy-based ingredients from Objective 1. Further physical characterization of the nanoemulsion made from the water-insoluble sugar polymer indicates that heating the mixture above 20°C (up to 60°C) may further increase its stability, which would be beneficial for numerous agricultural and food products. The water-soluble sugar polymer from frost grape vines was shown to also form a nanoemulsions with physical properties that suggest it is highly stable and should not clump together to fall out of solution. Finally, early evidence suggests that our ultraviolet-absorbing soy-based ingredients itself may possibly form a nanoemulsion via high-pressure homogenization that could allow this product to be used for several unexplored applications.
Under Objective 3, significant progress was made in developing chemocatalytic conversion processes to convert crop residues and new row crops to industrial chemicals. Advances in the use of the new row crop Cuphea were made after the testing of several catalysts led to one that effectively made a biobased, sustainable detergent products. Progress was made in the conversion of corn residues to commercial chemicals. Catalyst testing has led to methods that yield acetol and hydroxybutanone. Acetol is widely used in the chemical, textile, and food flavoring industries. The production of acetol from corn cobs promises a new revenue stream for corn growers and biorefinery operators. In other research, progress was made, in cooperation with an industry partner, in the production of the antibiotic tunicamycin at a commercially relevant scale. Tunicamycin is an antibiotic that enhances the antimicrobial activity of penicillins, but it is too toxic to be used clinically. Chemocatalytic technology was developed to modify this compound into a less toxic derivative that still retains its antimicrobial action. Several catalysts were tested until two were selected that will give nontoxic versions of this penicillin enhancer. This has allowed for an ARS animal disease researcher to examine the tunicamycin derivatives in the fight against bovine respiratory disease organisms.
Accomplishments
1. Improved production of non-toxic antibiotic enhancers. Penicillins are a class of antibiotics that are used to treat a wide range of bacterial infection; however, their effectiveness has been limited over the years with the development of antibiotic resistant microbes. Tunicamycin is a powerful antibiotic that can be combined with penicillins to overcome this resistance, but its toxicity in human and animals prevent it from being used for therapeutic applications. ARS researchers in Peoria, Illinois, have developed technology to chemically modify tunicamycin into less harmful derivatives while still retaining the ability to enhance penicillins. These methods utilize solid catalysts (a substance used to initiate or speed up chemical reactions) developed by the researchers to selectively alter specific chemical bonds in the tunicamycin that were shown to be associated with toxicity. The catalyst can then be easily removed from the reaction, resulting in a clean, safer tunicamycin derivative that can be used for numerous agricultural applications. This technology will allow stakeholders to potentially reduce the use of traditional antibiotics to treat livestock, which will delay antibiotic resistance, and reinstitute shelved antibiotics rendered ineffective due to antimicrobial resistance.
2. Photoprotective compounds from soybean oil. Recent consumer trends demanding “clean labeling” and natural, plant-based bioactives in their personal care and health and beauty aid products offers a unique opportunity to expand the use of commodity crops into non-traditional, higher-value markets. ARS researchers in Peoria, Illinois, previously developed a pilot-scale, bioreactor process for producing naturally modified, soy-based compounds with ultraviolet absorbing and antioxidant properties useful in the personal care and health and beauty aid markets. The researchers recently developed methods to measure the ultraviolet absorbance, photostability, and antioxidant capacities of the soy-based compounds and found that they performed as well as or better than currently used, petroleum-based active ingredients. These results demonstrate the efficacy and fungibility of the naturally modified soy-based compounds to industry partners and end users. The development of higher-value, commodity crop-based bioproducts benefits farmers by creating nonfood/nonfuel based agricultural markets, which enhances the profitability of small- and medium-sized agribusinesses, including biorefineries, which in turn benefits the local rural economy.
Review Publications
Evans, K.O., Compton, D.L., Appell, M.D. 2018. Determination of pH Effects Phosphatidyl-hydroxytyrosol and Phosphatidyl-tyrosol bilayer behavior. Methods and Protocols. 1(4):41. doi:10.3390/mps1040041.
Hou, C.T., Ray, K.J. 2018. Optimization of media and reaction conditions for production of polyol oils from soybean oil by Pseudomonas aeruginosa E03-12 NRRL B-59991. Biocatalysis and Agricultural Biotechnology. 17:135-141. https://doi.org/10.1016/j.bcab.2018.10.006.
Jackson, M.A., Price, N.P., Blackburn, J.A., Peterson, S.C., Kenar, J.A., Haasch, R., Chen, C. 2019. Partial hydrodeoxygenation of corn cob hydrolysate over palladium catalysts to produce 1-hydroxy-2-pentanone. Applied Catalysis A: General. 577:52-61. https://doi.org/10.1016/j.apcata.2019.03.019.
Evans, K.O., Compton, D.L., Kim, S., Appell, M.D. 2019. Charged phospholipid effects on AAPH oxidation assay as determined using liposomes. Chemistry and Physics of Lipids. 220:49-56. https://doi.org/10.1016/j.chemphyslip.2019.02.004.
Appell, M., Evans, K.O., Jackson, M.A., Compton, D.L. 2019. Determination of ochratoxin A in grape juice and wine using nanosponge solid phase extraction clean-up and liquid chromatography with fluorescence detection. Journal of Liquid Chromatography and Related Technologies. 41:949-954. https://doi.org/10.1080/10826076.2018.1544148.
