xylose is detected in blood and/or urine within the next few hours, it has been absorbed by the intestines. High xylose intake on the order of approximately 100 g/kg of animal body weight is relatively well tolerated in pigs, and in a similar manner to results from human studies, a portion of the xylose intake is passed out in urine undigested. Hydrogen production In 2014 a low-temperature , atmospheric-pressure enzyme-driven process to convert xylose into hydrogen with nearly 100% of the theoretical yield was announced. The process employs 13 enzymes, including a novel polyphosphate xylulokinase (XK). Derivatives Reduction of xylose by catalytic hydrogenation produces the sugar substitute xylitol. See also Saccharophagus degradans Xylonic acid Xylose metabolism References Aldopentoses