Genotype-Specific Changes in Vitamin B₆Content and the PDX Family in Potato

Abstract

Vitamin B6 is one of the most versatile cofactors in plants and an essential phytonutrient in the human diet that benefits a variety of human health aspects. Although biosynthesis of the vitamin has been well resolved in recent years, the main research is currently based on Arabidopsis thaliana with very little work done on major crop plants. Here we provide the first report on interactions and expression profiles of PDX genes for vitamin B6 biosynthesis in potato and how vitamin B6 content varies in tubers of different genotypes. The results demonstrate that potato is an excellent resource for this vitamin and that strong natural variation in vitamin B6 content among the tested cultivars indicates high potential to fortify vitamin B6 nutrition in potato-based foods.

Effect of low‐temperature storage on the content of folate, vitamin B6, ascorbic acid, chlorogenic acid, tyrosine, and phenylalanine in potatoes

“…23 There were additional increases after reconditioning. 16 Mooney et al 13 previously showed that the wileyonlinelibrary.com/jsfa Defender and Premier Russet varieties accumulated up to 42% and 23%, respectively, more vitamin B 6 after storage for 227 days at 6.7 or 8.9 ∘ C. Together, these data indicate that there is a trend towards an increase in vitamin B 6 content during cold storage, regardless of varieties and growth conditions. Like folates, B 6 vitamers have direct non-cofactor antioxidant activities and Arabidopsis plants with enhanced levels of vitamin B 6 are more tolerant to oxidative stress.…”

“…There were additional increases after reconditioning . Mooney et al previously showed that the Defender and Premier Russet varieties accumulated up to 42% and 23%, respectively, more vitamin B 6 after storage for 227 days at 6.7 or 8.9 °C. Together, these data indicate that there is a trend towards an increase in vitamin B 6 content during cold storage, regardless of varieties and growth conditions.…”

“…Vitamin B 6 was analyzed using a previously described yeast bioassay with a vitamin B 6 auxotrophic strain ATCC9080. 13 Total vitamin B 6 was extracted and measured according to Gonzalez et al 14 Data shown are averages of at least three biological replicates. Yeast growth rates at OD 540 were used to estimate total vitamin B 6 content in comparison to a pyridoxine-based standard curve.…”

Rationalising vitamin B6 biofortification in crop plants

“…Monotonous consumption of low micronutrient-containing staple crops can lead to dietary vitamin B 6 deficiency, which is further aggravated in some cases by post-harvest deterioration [4] and processing practices combined with the water-soluble nature of vitamin B 6 [16]. For example, polishing of rice grains is necessary to permit long-term storage, however, removal of the hull, aleurone layers and embryo depletes grains of important stores of dietary vitamins (including vitamin B 6 ) and other micronutrients, therefore lowering the nutritional value of the polished grain [17,18].…”

“…A B 6 vitamer source is essential for survival of all organisms but only microorganisms and plants can carry out biosynthesis de novo, hence animals and humans must obtain the vitamin from their diet (Figure 1). Dietary vitamin B 6 sources for humans include meat and fresh vegetables [4,5] but these food staples are not readily accessible or available in sufficient quality and quantities to all populations. Moreover, rice, wheat and cassava, which are three of the world's top five produced staple crops, are deficient (in terms of dietary value) for vitamin B 6 [6].…”