TECHNOLOGY FOCUS - BIOLOGY - Preferred Components: The microorganism is yeast. The lignocellulosic biomass is selected from switchgrass, waste paper, sludge from paper manufacture, corn grain, corn cobs, corn husks, corn stover, wood waste, grasses, wheat, wheat straw, hay, barley, barley straw, rice straw, sugar cane bagasse, sorghum, soy, components obtained from processing of grains, trees, branches, roots, leaves, wood chips, sawdust, shrubs and bushes, vegetables, fruits, flowers and/or animal manure.    TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: The method (M1) additionally involves: contacting the composition with a source of 6-carbon sugars. The 5-carbon and 6-carbon sugars are cumulatively consumed at a rate of at least 1.5 g/gdcw/h; are converted to butanol. The fermentable carbons are cumulatively consumed at a rate of at least 2 g/gdcw/h. The 5-carbon sugars and 6-carbon sugars are consumed, and the rate of 5-carbon sugar consumption is at least about 1% the rate of 6-carbon sugar consumption. The method (M1) further involves: contacting the composition with a suitable extractant where the butanol is recoverable; purifying butanol from the culture. Preferred Components: The enzyme or combination of enzymes capable of converting a 5-carbon sugar to xylulose or xylulose-5-phosphate are recombinantly expressed, are recombinantly expressed by the microorganism capable of producing butanol, are not produced by the microorganism capable of producing butanol or are not produced by a microorganism in the composition. The enzyme or combination of enzymes capable of converting a 5-carbon sugar to xylulose or xylulose-5-phosphate is selected from xylose isomerase; xylose reductase; xylitol dehydrogenase; arabinose isomerase; ribulokinase; ribulose-phosphate-5-epimerase; arabinose reductase; arabitol dehydrogenase; xylulose reductase; xylulokinase and/or aldose reductase. The xylose isomerase has the Enzyme Commission Number EC 5.3.1.5. The xylose reductase has the Enzyme Commission Number EC 1.1.1.9 or EC 1.1.1.10. The arabinose isomerase has the Enzyme Commission Number EC 5.3.1.4. The ribulokinase has the Enzyme Commission Number EC 2.7.1.16. The ribulose-phosphate-5-epimerase has the Enzyme Commission Number EC 5.1.3.4. The arabitol dehydrogenase has the Enzyme Commission Number EC 1.1.1.12. The xylulokinase has the Enzyme Commission Number EC 2.7.1.17. The aldose reductase has the Enzyme Commission Number EC 1.1.1.21. The source of 5-carbon sugars is a source of xylose, or source of arabinose, source of 6-carbon sugars. The 5-carbon sugars are converted to butanol. The source of 5-carbon sugars is lignocellulosic biomass. The lignocellulose biomass is pretreated with ammonia. The source of 5-carbon sugars is present at a concentration of at least 20 (preferably at least 50, especially at least 75) g/l. The microorganism capable of producing butanol comprises polynucleotides encoding polypeptides that catalyze the conversion of: pyruvate to acetolactate; acetolactate to 2,3-dihydroxyisovalerate; 2,3-dihydroxyisovalerate to 2-ketoisovalerate; 2-ketoisovalerate to isobutyraldehyde; and isobutyraldehyde to isobutanol. The microorganism capable of producing butanol comprises polynucleotides encoding polypeptides having acetolactate synthase, keto acid reductoisomerase, dihydroxy acid dehydratase, ketoisovalerate decarboxylase, and alcohol dehydrogenase activity; at least one deletion, mutation, and/or substitution in an endogenous polynucleotide encoding a polypeptide having pyruvate decarboxylase activity. The polypeptide having pyruvate decarboxylase activity is selected from Pdc1, Pdc5 and/or Pdc6. The microorganism capable of producing butanol is free of an enzyme having pyruvate decarboxylase activity. The microorganism capable of producing butanol is PNY1504. The culturing is in a fermenter. The inhibitor of respiration is added to the composition. The inhibitor is Antimycin A. The microorganism capable of producing butanol is present at a concentration that is in excess of the concentration of the microorganism that is not capable of producing butanol. The microorganism is capable of producing butanol; an enzyme or combination of enzymes capable of converting a 5-carbon sugar to xylulose or xylulose-5-phosphate; source of 5-carbon sugars; and fermentation media. The microorganism capable of producing butanol is Saccharomyces cerevisiae. The microorganism capable of producing butanol is present at a concentration that is at least equivalent to the concentration of the microorganism that do not produce butanol.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The specific butanol production is at least 0.4 g/g/h. The purification of butanol from the culture involves extraction in oleyl alcohol. Preferred Composition: The composition and/or the source of 5-carbon sugars further comprises a microorganism that is not capable of producing butanol, and the microorganism capable of producing butanol is present at a concentration that is at least equal to 1 g/l. The composition (c2) additionally comprises a source of 6-carbon sugars; an inhibitor of respiration; microorganism that does not produce butanol. EXAMPLE - No suitable example given.