Influence of Uv-Light on the Antioxidative Capacity of Extracts From Spinacia Oleracea L. And Gynura Bicolor (Willd.) Dc

Summer (Subarctic) versus Winter (Subtropic) Production Affects Spinach (Spinacia oleracea L.) Leaf Bionutrients: Vitamins (C, E, Folate, K1, provitamin A), Lutein, Phenolics, and Antioxidants

“…Folate was higher in all leaves grown under the subarctic summer solstice and, except for middle canopy leaves, folate was higher in ‘Lazio’ than ‘Samish’ (Figure D). Higher levels of folate in middle and top canopy versus bottom canopy leaves has been previously reported for spinach, collard, mustard, and turnip greens; folate concentrations are expected to be higher in the upper canopy, as folate is synthesized only in mitochondria, which are abundant in rapidly growing leaves and fruits . Knowledge of folate biosynthesis and its regulation is fragmentary, as no coherent overall picture has emerged .…”

“…The two locations allowed for differences in solar angle of the sun, depth of the ozone column, and cloud dispersion of light during the respective growing seasons. These factors influenced the A+B ultraviolet light spectra (280–400 nm), which can have quantitative effects on spinach AsA, β-carotene, and lutein and leaf antioxidant capacities . These environmental differences also had a profound effect on plant growth rate between locations, which in turn affected dry matter content (Table ); therefore, where appropriate, nutrients were expressed on a dry weight basis.…”

Changes in polyphenol biosynthesis induced inGynura bicolorDC. leaves by infrared irradiation

“…Its leaves are characteried by having green adaxial and reddish-purple abaxial surfaces. G. bicolor leaves are a effective source of natural anti-oxidants and contain high amounts of anthocyanins (Hayashi et al, 2002) and phenolic acids (Schirrmacher et al, 2007). In Ishikawa Prefecture, G. bicolor leaves are cultivated in the field from earlySpring to late-Autumn.…”