In enzymology, a L-arabinose 1-dehydrogenase (EC 1.1.1.46) is an enzyme that catalyzes the chemical reaction

L-arabinose + NAD⁺ ${\displaystyle \rightleftharpoons }$ L-arabinono-1,4-lactone + NADH + H⁺

Thus, the two substrates of this enzyme are L-arabinose and NAD⁺, whereas its 3 products are L-arabinono-1,4-lactone, NADH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is L-arabinose:NAD⁺ 1-oxidoreductase. This enzyme participates in ascorbate and aldarate metabolism.

• Weimberg R, Doudoroff M (December 1955). "The oxidation of L-arabinose by Pseudomonas saccharophila". The Journal of Biological Chemistry. 217 (2): 607–24. PMID 13271422.