HPLC analysis of l-[1-14C]arabinose (catalog no. ARC 1041 [American Radiolabeled Chemicals]; lot 011110). A solution containing 1 mg · ml−1 each of d-xylose (X), l-xylulose (Xu), l-arabinose (A), l-arabitol (Atol), and xylitol (Xtol) and 1.9 × 106 cpm · ml of l-[1-14C]arabinose (catalog no. ARC 1041; lot 011110) was prepared in water, and 45 μl was injected into the HPLC system. After 70 min at a flow rate of 0.15 ml · min−1, 440-μl fractions were collected, and their radioactivities were determined. The retention times of the standards are indicated by the arrows.