Idaho Research Foundation, Inc.

Donald L Crawford

Ronald L Crawford

Todd O Stevens

Maria B Pasti

Stefan Goszczynski

Andrzej Paszczynski

Muralidhara Ramachandra

Stephen B Funk

Lisa J Pumfrey

Karl M Regan

Hyung W Suh

Methods for biodegrading nitroaromatic compounds present as contaminants in soil or water using microorganisms are disclosed. Water is treatable directly; dry soil is first converted into a fluid medium by addition of water. The preferred method comprises two stages, each employing microorganisms: a fermentative stage, followed by an anaerobic stage. The fermentative stage is rapid, wherein an inoculum of aerobic and/or facultative microorganisms ferments a carbohydrate added to the fluid medium, exhausting the oxygen in the fluid medium and thereby inhibiting oxidative polymerization of amino by-products of the nitroaromatics. In the subsequent anaerobic stage, an inoculum of a mixed population of anaerobic microorganisms completes the mineralization of the contaminant nitroaromatics, using the remaining carbohydrate as a carbon and energy source. Preferably, the carbohydrate is a starch and the aerobic and/or facultative microorganisms are amylolytic, which cleave the starch at a moderate rate throughout both stages, ensuring a sustained supply of metabolizable carbohydrate. The microorganisms are preferably selected to be resistant to the types and concentrations of nitroaromatics present as contaminants.

Biological system for degrading nitroaromatics in water and soils

Novel methods for biodegrading nitroaromatic compounds present as contaminants in soil or water using microorganisms are disclosed. Water is treatable directly; dry soil is first converted into a fluid medium by addition of water. The preferred method comprises two stages, each employing microorganisms: a fermentative stage, followed by an anaerobic stage. The fermentative stage is rapid, wherein an inoculum of aerobic and/or facultative microorganisms ferments a carbohydrate added to the fluid medium, exhausting the oxygen in the fluid medium and thereby inhibiting oxidative polymerization of amino by-products of the nitroaromatics. In the subsequent anaerobic stage, an inoculum of a mixed population of anaerobic microorganisms completes the mineralization of the contaminant nitroaromatics, using the remaining carbohydrate as a carbon and energy source. Preferably, the carbohydrate is a starch and the aerobic and/or facultative microorganisms are amylolytic, which cleave the starch at a moderate rate throughout both stages, ensuring a sustained supply of metabolizable carbohydrate. The microorganisms are preferably selected to be resistant to the types and concentrations of nitroaromatics present as contaminants.

Use of streptomyces bacteria to control plant pathogens and degrade turf

A composition comprises an azo dye having a lignin-like substitution pattern and an environmentally common microbe, such as Streptomyces or Phanerochaete chrysosporium. The composition may also comprise an azo dye having a lignin-like substitution pattern, an amount of lignin peroxidase effective to degrade the dye, and an amount of veratryl alcohol effective to recycle lignin peroxidase II to lignin peroxidase. The lignin peroxidase may be provided by an environmentally common microbe. Azo dyes substituted with lignin-like groups are completely mineralized by the environmentally common microbe. The biodegradable azo dye preferably includes a first aromatic ring having a first substituent R1 selected from hydroxy or lower alkoxy, a second substituent R2 selected from lower alkyl or lower alkoxy, and a third substituent R3 selected from lower alkoxy or halogen. In especially preferred embodiments the first substituent R.sub.1 is hydroxy and is para to the azo group, and both R.sub.2 and R.sub.3 are electron-releasing substituents and are ortho to R.sub.1.

Biodegradable azo dyes

This invention relates to a biocontrol formulation suitable for reducing the susceptibility of plants to fungal phytopathogens. In one aspect of the invention, a newly isolated strain of Streptomyces, Streptomyces YCED 9, is incorporated into a suitable delivery medium and applied to plant seeds or plant roots.

Use of streptomyces bacteria to control plant pathogens

A biodegradable azo dye contains a nitrogen atom linked to an aromatic ring having a lignin-like substitution pattern. The ring is preferably a syringyl or guaiacol moiety, and provides a naturally-occurring structure for attack by microorganisms, such as Streptomyces or Phanerochaete. In especially preferred embodiments, the aromatic ring has a first substituent R.sub.1 selected from among hydroxy, lower alkoxy, or amino, and a second substituent R.sub.2 selected from among lower alkyl, lower alkoxy and halogen. Some embodiments include a third ring substituent R.sub.3 selected from the group lower alkyl, lower alkoxy, and halogen.

Three individual strains of anaerobic microorganisms are disclosed. Each has an ability to degrade nitroaromatic and nitramine compounds under anaerobic conditions. The strains, identified as LJP-1, SBF-1, and KMR-1, appear to be of Clostridium bifermentans. The strains were isolated from consortia of anaerobic microorganisms grown in a chemostat in which the 'munitions' compounds TNT (as a representative nitroaromatic) and 'RDX' nad 'HMX' (as representative nitramines) were administered as sole sources of carbon for the microorganisms. The isolated strains, either individually or as mixtures thereof, can be used in methods for degrading, under anaerobic conditions (i.e., redox potential &lt;-200 mV), a contaminant nitroaromatic and/or nitramine compound in water or soil (as an aqueous slurry, i.e., 'fluid medium'). The strains will degrade nitroaromatics and nitramines in such fluid media either alone or with other microorganisms present in the fluid medium.

Biological isolates for degrading nitroaromatics and nitramines in water

This invention relates to a biocontrol formulation suitable for reducing the susceptibility of plants to fungal phytopathogens. In one aspect of the invention, a newly isolated strain of Streptomyces, Streptomyces WYEC 108, is incorporated into a suitable delivery medium and applied to plant seeds or plant roots.

Use of Streptomyces WYEC 108 to control plant pathogens

Novel methods for biodegrading nitroaromatic compounds present as contaminants in soil or water using microorganisms are disclosed. Water is treatable directly; dry soil is first converted into a fluid medium by addition of water. The preferred method comprises two stages, each employing microorganisms: a fermentative stage, followed by an anaerobic stage. The fermentative stage is rapid, wherein an inoculum of aerobic and/or facultative microorganisms ferments a carbohydrate added to the fluid medium, exhausting the oxygen in the fluid medium and thereby inhibiting oxidative polymerization of amino by-products of the nitroaromatics. In the subsequent anaerobic stage an inoculum of a mixed population of anaerobic microorganisms completes the mineralization of the contaminant nitroaromatics, using the remaining carbohydrate as a carbon and energy source. Preferably, the carbohydrate is a starch and the aerobic and/or facultative microorganisms are amylolytic, which cleave the starch at a moderate rate throughout both stages, ensuring a sustained supply of metabolizable carbohydrate. The microorganisms are preferably selected to be resistant to the types and concentrations of nitroaromatics present as contaminants.

DNA constructs are provided for the production of Streptomyces lignin peroxidase. The enzyme finds use in the degradation of lignin and oxidation of organic substrates.

Bacterial extracellular lignin peroxidase

A newly discovered lignin peroxidase enzyme is provided. The enzyme is obtained from a bacterial source and is capable of degrading the lignin portion of lignocellulose in the presence of hydrogen peroxide. The enzyme is extracellular, oxidative, inducible by lignin, larch wood xylan, or related substrates and capable of attacking certain lignin substructure chemical bonds that are not degradable by fungal lignin peroxidases.

Growing community of inventors

Moscow, ID, United States of America

Donald L Crawford