Patent Number: 
Section: claims

1. A method, comprisinga) providing sugarcane billets of a predetermined thickness;b) irradiating the cut side of sugarcane billets with Ultraviolet-C or Ultraviolet-B light or combinations thereof at an intensity and for a duration of time sufficient to produce a significant increase in a level of one or more stilbenes in the irradiated billets compared to a level of stilbenes in billets that are not irradiated;c) maintaining the irradiated sugarcane billets for at least about three days up to about 20 days; andd) selecting the irradiated sugarcane billets. 2. The method of claim 1, wherein the irradiated sugarcane billets are maintained in step (c) at a level of light that does not cause stilbene isomerization. 3. The method of claim 1, wherein the sugarcane billets range from about 2 mm to about 50 mm in thickness. 4. The method of claim 1, wherein the intensity of UVB light ranges from about 10 mW/cm2 to about 50 W/cm2. 5. The method of claim 1, wherein the intensity of UVC light ranges from about 1 mW/cm2 to about 25 mW/cm2. 6. The method of claim 1, wherein the duration of irradiation ranges from about 10 minutes to about 3 hours. 7. The method of claim 1, wherein the stilbene is resveratrol. 8. The method of claim 1, wherein the stilbene is piceatannol. 9. The method of claim 1, wherein the temperature during step (b) is maintained at a temperature between about 20 degrees Centigrade to about 40 degrees Centigrade. 10. The method of claim 1, wherein the temperature during step (c) is maintained at a temperature between about zero degrees Centigrade and to about 40 degrees Centigrade. 11. The method of claim 1, further comprisinge) extracting one or more stilbenes from the irradiated billets after step (c). 12. The method of claim 1, wherein the stilbenes are in the trans form. 13. The method of claim 1, wherein the sugarcane billets are maintained in step (c) from about 7 up to about 20 days after irradiation. 14. The method of claim 1, wherein the sugarcane billets in step (a) are obtained from sugarcane that was inoculated with a fungus that increases stilbene production in the sugarcane. 15. The method of claim 14, wherein the fungus is Collectotrichum falcatum or Aspergillus sojae.  16. The method of claim 1, wherein the sugarcane is a member selected from the group consisting of the variety cv L 97-128, cv HO95 and cv LCP. 17. Sugarcane billets made by the method according to claim 1. 18. The sugarcane billets of claim 17, wherein the stilbene is resveratrol ranging from about 10 μg/g to about 500 μg/g. 19. The sugarcane billets of claim 17, wherein the stilbene is piceatannol ranging from 100 μg/g to 10,000 μg/g. 20. The sugarcane billets of claim 17, wherein the sugarcane is a member selected from the group consisting of the variety cv L 97-128, cv HO95 and cv LCP. 21. Bagasse obtained from the sugarcane billets of claim 17. 22. Biofuel made from the bagasse of sugarcane billets of claim 17. 23. A method comprisinga) providing sugarcane leaves of a predetermined thickness;b) irradiating the sugarcane leaves with Ultraviolet-C or Ultraviolet-B light or combinations thereof at an intensity and for a duration of time sufficient to produce a significant increase in a level of one or more stilbenes in the irradiated leaves compared to a level of stilbenes in leaves that are not irradiated; andc) maintaining the irradiated sugarcane leaves for at least about three days before selecting the irradiated sugarcane leaves. 24. Sugarcane leaves made according to the method of claim 23. 25. A method, comprisinga) providing sugarcane billets between 2 mm and 50 mm in thickness;b) maintaining the sugarcane for at least about three days up to about 20 days at a level of light that prevents stilbene isomerization at zero degrees Centigrade and to about 40 degrees Centigrade; andc) then selecting the sugarcane billets, wherein the billets are enriched in stillbenes. 26. The sugarcane billets made by the method of claim 25.