Antimicrobial and anti-inflammatory activity of switchgrass-derived extractives

Abstract

Switchgrass is an increasingly important biofuel crop, but knowledge of switchgrass fungal pathogens is not extensive. The purpose of this research was to identify the fungal pathogens that decrease crop yield of switchgrass grown in Tennessee and to investigate a potential sustainable disease management strategy from a value-added by-product of the switchgrass biofuel conversion process. The specific objectives were 1) to identify and characterize prevalent fungal pathogens of switchgrass in Tennessee, 2) assess switchgrass seed produced in the United States for seedborne fungal pathogens, and 3) evaluate switchgrass extractives for antimicrobial activity against plant pathogens.

1 . (canceled) 
     
     
         2 . A composition comprising a solvent soluble extract of switchgrass. 
     
     
         3 . A method for processing  Panicum virgatum  L. (switchgrass) biomass, the method comprising:
 a) obtaining a switchgrass biomass,   b) treating the switchgrass biomass with a solvent and separating the solvent-soluble extractives portion of the switchgrass biomass from the cellulosic and/or lignocellulosic portion of the switchgrass biomass, and   c) optionally, producing a biofuel from the cellulosic and/or lignocellulosic portion of the switchgrass biomass.   
     
     
         4 . The method of  claim 3 , wherein said method comprises producing a biofuel from the cellulosic and/or lignocellulosic portion of the switchgrass biomass. 
     
     
         5 . The method of  claim 3 , wherein the solvent extraction process is a single solvent extraction process. 
     
     
         6 . The method of  claim 3 , wherein the solvent is a polar solvent. 
     
     
         7 . The method of  claim 5 , wherein the polar solvent is ethanol. 
     
     
         8 . The method of  claim 5 , wherein the solvent soluble extractives portion comprises fatty acids, fatty alcohols, glycerol, alkanes and sterols. 
     
     
         9 . The method of  claim 3 , wherein the solvent is water. 
     
     
         10 . The method of  claim 9 , wherein the solvent soluble extractives portion comprises antioxidants selected from α-tocopherol, policosanol, or a combination thereof. 
     
     
         11 . The method of  claim 10 , wherein the solvent extractives portion further comprises phenolic compounds selected from p-coumaric acid, ferulic acid, sinapic acid, or a combination thereof. 
     
     
         12 . A method of preventing or treating an infection by an infectious agent in a plant, the method comprising administering an effective amount of a solvent soluble switchgrass extract according to  claim 2  to the plant. 
     
     
         13 . The method of  claim 12 , wherein the plant is a tomato plant. 
     
     
         14 . The method of  claim 13 , wherein the infectious agent is a bacterium. 
     
     
         15 . The method of  claim 14 , wherein the bacterium is selected from  Clavibacter michiganensis  subsp.  michiganensis, Xanthomonas perforans, Pseudomonas syringae  pv. Tomato or  Pseudomonas mediterranea.    
     
     
         16 . The method of  claim 12 , wherein the infectious agent is a fungus. 
     
     
         17 . The method of  claim 16 , wherein the fungus is  Fusarium  spp. 
     
     
         18 . The method of  claim 17 , wherein the fungus is  Fusarium oxysporum.    
     
     
         19 . A method of preventing spoilage of a food product or inhibiting a food-borne pathogen in a food product, the method comprising administering an effective amount of a solvent soluble switchgrass extract according to  claim 2  to the food product. 
     
     
         20 . The method of  claim 19 , wherein the food-borne pathogen is  Salmonella typhimurium, Salmonella enteritidis  or  Staphylococcus aureus.    
     
     
         21 . A method of treating inflammation in a subject, the method comprising administering an effective amount of a solvent soluble switchgrass extract according to  claim 2  to a subject. 
     
     
         22 . A method of treating obesity in a subject, the method comprising administering an effective amount of the solvent-soluble switchgrass extract according to  claim 2  to a subject.