Rationalising vitamin B6 biofortification in crop plants

Abstract

Vitamin B₆ encompasses a group of related compounds (vitamers) that can only be biosynthesised de novo by plants and microorganisms. Enzymatic cofactor and antioxidant functions for vitamin B₆ are established in all kingdoms. Human vitamin B₆ dietary insufficiency or genetic defects in B₆ vitamer interconversion result in various neurological and inflammatory pathologies with several populations at-risk or marginal for vitamin B₆ status. Three (rice, wheat and cassava) of the world's top five staple crops do not meet the recommended dietary allowance for vitamin B₆, when consumed as a major proportion of the diet. In addition, controlled enhancement of the appropriate B₆ vitamer in crops has the potential to confer stress resistance. Thus, crop biofortification strategies represent an opportunity to reduce the risk of deficiency in populations with limited diet diversity and quality, as well as improving stress tolerance.