Biosynthesis and accumulation of multi‐vitamins in black sweet corn (Zea mays L.) during kernel development

Abstract

BACKGROUND: Black sweet corn as an edible fruit has various nutritional qualities. This study discusses changes in the vitamin C and E, folate, and carotenoid content during black sweet corn maturation, and also the effects of preharvest weather conditions and of related genes in multi-vitamin biosynthesis pathways. RESULTS: Most vitamin levels improved, especially vitamin C and carotenoid levels, while the folate content dropped rapidly. Transcript levels of most genes in folate biosynthesis showed trends that were similar to the content changes. VTC2 and GLDH, which are regulated by light, had high expression levels leading to an increase in ascorbate content during maturation. γ-Tocotrienol is the main vitamin E component, and HGGT, the key gene controlling the synthesis of tocotrienols, had a much higher expression level than other genes. Lutein and zeaxanthin were the dominant carotenoid components. A rapid reduction in the transcription level of LCYε could result in a lower lutein production rate. CONCLUSION: Black sweet corn has a high nutritional value and is rich in vitamins, including zeaxanthin, γ-tocotrienols, and ascorbic acid. The best harvest time is between 20-25 days after pollination (DAPs) when kernels had a good taste as well as relatively high vitamin levels.

Effect of Steaming on Vitamin Retention in Tubers from Eight Cultivars of Potato (Solanum tuberosum L.)

“…The study evaluated levels and retention upon steaming of vitamins in potatoes tubers within one week after the harvest because the storage under low temperature caused the decrease of vitC and the increase of pyridoxine and vitB9 [21]. In raw tubers of potato cultivars grown in northern China, vitB9 levels (48.84-131.68 µg/100 g DW) were at a similar range to those of cultivars grown in the Americas [22] (46.3-233.7 µg/100 g DW; Table 5); VitC levels were slightly higher (46.47-155.44 mg/100 g FW) than those of American cultivars [23] (10-40 mg/100 g FW; Table 2); VitE levels (15.34-33.84 mg/kg DW; Table 5) were lower than those reported in seeds of species including barley [24,25] (50-55 mg/kg DW), black sweet corn [26] (74.14 mg/kg DW), and soybean [20] (266-421 mg/kg DW; Table 5). Similar to that tocotrienol is the main form of vitE in most monocotyledons, and some dicotyledons [4], the proportion of tocotrienol was 42.9-68.5% (Table 5).…”

Regulation of Plant Vitamin Metabolism: Backbone of Biofortification for the Alleviation of Hidden Hunger

“…In the metabolic engineering of cassava, simultaneous overexpression of DXS and PSY was more effective in elevating carotenoid levels than that of PSY alone (Sayre et al, 2011). Similarly, GTP is required for the biosynthesis of not only ascorbate but also folates and riboflavin by the action of GTP cyclohydrolases I and II, respectively (Herz et al, 2000;Hu et al, 2020). Tocochromanols, on the other hand, require precursors from the MEP and shikimate pathways, which also supply precursors for carotenoids and folates, respectively .…”

Vitamin E and carotenoid accumulation during kernel development in two varieties of Castanea henryi

“…The sudden reduction of the total carotenoid content at S5 in WS was likely to upregulate PSY expression with 9.2‐fold of S4 through negative feedback regulation (Welsch et al ., 2017), whereas in YS, the total carotenoid contents and the PSY expression levels showed no significant difference between S4 and S5. In addition, the expressions of ζ‐carotene desaturase ( PDS ) maintained relatively high levels during the development period with small fluctuations, which were consistent with the variations occurring in black sweet corn (Hu et al ., 2020). ζ‐carotene desaturase ( ZDS ) and prolycopene isomerase ( CRTISO ) reached the highest expression levels at S3 in WS and potentially behaved as over 30% increase in total carotenoids content as compared with S2.…”

“…Fruit ripening involves changes in nutrient substances including vitamin E and carotenoids (Georgiadou et al ., 2016; Lado et al ., 2016; Cao et al ., 2017; Hu et al ., 2020), but there are limited studies on the varieties of vitamin E and carotenoids in chestnut fruit, especially in C. henryi . In addition, to the nutritional value and health benefits of vitamin E and carotenoids, this research focuses on the changes of vitamin E and carotenoids contents as well as the key gene expression of biosynthetic pathways in two varieties of C. henryi during the development.…”