Elevated vitamin E content improves all-trans β-carotene accumulation and stability in biofortified sorghum.
Micronutrient deficiencies are common in locales where people must rely upon sorghum as their staple diet. Sorghum grain is seriously deficient in provitamin A (β-carotene) and in the bioavailability of iron and zinc. Biofortification is a process to improve crops for one or more micronutrient deficiencies. We have developed sorghum with increased β-carotene accumulation that will alleviate vitamin A deficiency among people who rely on sorghum as their dietary staple. However, subsequent β-carotene instability during storage negatively affects the full utilization of this essential micronutrient. We determined that oxidation is the main factor causing β-carotene degradation under ambient conditions. We further demonstrated that coexpression of homogentisate geranylgeranyl transferase (HGGT), stacked with carotenoid biosynthesis genes, can mitigate β-carotene oxidative degradation, resulting in increased β-carotene accumulation and stability. A kinetic study of β-carotene degradation showed that the half-life of β-carotene is extended from less than 4 wk to 10 wk on average with HGGT coexpression.
DuPont Pioneer, Johnston, IA 50131;
Ping
P
Che
DuPont Pioneer, Johnston, IA 50131; zuo-yu.zhao@pioneer.com marc.albertsen@pioneer.com.
Zuo-Yu
ZY
Zhao
DuPont Pioneer, Johnston, IA 50131;
Kimberly
K
Glassman
DuPont Pioneer, Johnston, IA 50131;
David
D
Dolde
DuPont Pioneer, Johnston, IA 50131;
Tiger X
TX
Hu
DuPont Pioneer, Johnston, IA 50131;
Todd J
TJ
Jones
Darren Fred
DF
Gruis
Africa Harvest Biotech Foundation International, Nairobi 00621, Kenya.
Silas
S
Obukosia
Africa Harvest Biotech Foundation International, Nairobi 00621, Kenya.
Florence
F
Wambugu
DuPont Pioneer, Johnston, IA 50131; zuo-yu.zhao@pioneer.com marc.albertsen@pioneer.com.
Marc C
MC
Albertsen
D002851:Chromatography, High Pressure Liquid; D004269:DNA, Bacterial / Q000235:genetics; D056625:Endosperm / Q000378:metabolism; D005527:Food, Fortified; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D012639:Seeds / Q000378:metabolism; D045868:Sorghum / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D014810:Vitamin E / Q000378:metabolism*; D019207:beta Carotene / Q000378:metabolism*
D004269:DNA, Bacterial; D010940:Plant Proteins; C036483:T-DNA; D019207:beta Carotene; D014810:Vitamin E
HGGT; biofortified sorghum; vitamin E; β-carotene accumulation; β-carotene stability