Recent advances in properties, production, and applications of L-ribulose.

Currently, due to the special functions and potential application values, rare sugars become the hot topic in carbohydrate fields. L-Ribulose, an isomer of L-ribose, is an expensive rare ketopentose. As an important precursor for other rare sugars and L-nucleoside analogue synthesis, L-ribulose attracts more and more attention in recent days. Compared with complicated chemical synthesis, the bioconversion method becomes a good alternative approach to L-ribulose production. Generally, the bioconversion of L-ribulose was linked with ribitol, L-arabinose, L-ribose, L-xylulose, and L-arabitol. Herein, an overview of recent advances in the metabolic pathway, chemical synthesis, bioproduction of L-ribulose, and the potential application of L-ribulose is reviewed in detail in this paper. KEY POINTS: 1. L-Ribulose is a rare sugar and the key precursor for L-ribose production. 2. L-Ribulose is the starting material for L-nucleoside derivative synthesis. 3. Chemical synthesis, bioproduction, and applications of L-ribulose are reviewed.