Ageing and irradiance enhance vitamin E content in green edible tissues from crop plants

• Published in: Journal of the science of food and agriculture Vol. 90; no. 12; pp. 1994 - 1999
• Main Authors: Lizarazo, Karol, Fernández-Marín, Beatriz, Becerril, José María, García-Plazaola, José Ignacio
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.09.2010; Wiley; John Wiley and Sons, Limited
• Subjects: abiotic stress; Agriculture - methods; alpha-tocopherol; Antioxidants - analysis; Biological and medical sciences; chemical constituents of plants; crop production; Crops; Crops, Agricultural - chemistry; Crops, Agricultural - growth & development; Crops, Agricultural - radiation effects; Cucumis sativus; environmental stress; food composition; Food industries; Food science; Fruit - chemistry; Fruit - growth & development; Fruit - radiation effects; Fundamental and applied biological sciences. Psychology; harvest date; Humans; irradiance; irradiation; leaves; Light; lipophilic antioxidants; Magnoliopsida - chemistry; Magnoliopsida - growth & development; Magnoliopsida - radiation effects; nutraceuticals; Nutritive Value; Photons; photoprotection; plant age; plant stress; Plant Structures; senescence; Spinacia oleracea; Stress, Physiological; synergism; Time Factors; Tissues; tocopherols; Vegetables; Vegetables - chemistry; Vegetables - growth & development; Vegetables - radiation effects; vitamin content; Vitamin E; Vitamin E - analysis; vitamins; Tissue; environmental stress; vitamins; Vitamin E; Ageing; nutraceuticals; photoprotection; irradiance; Antioxidant; lipophilic antioxidants; Stress; Green
• ISSN: 0022-5142; 1097-0010; 1097-0010
• DOI: 10.1002/jsfa.4043

BACKGROUND: Tocopherol (vitamin E) is an antioxidant essential in human nutrition. Several approaches have aimed to enhance tocopherol content in crops by the genetic modification of plants, a practice that generates some social concern. As tocopherol accumulates with leaf age in some wild plants and the antioxidant mechanisms respond with flexibility to stress conditions, it is hypothesised that tocopherol content can be increased in edible plants by the manipulation of harvesting time and growth conditions, in particular irradiance.RESULTS: Ontogenic changes in tocopherol concentration have been studied in photosynthetic tissues of edible leaves (lettuce, spinach, corn salad and dandelion) and green fruits (cucumber and pepper). In all species, tocopherol content increased with tissue age. Spinach showed the fastest rate of tocopherol accumulation, and growth at higher irradiance had a synergistic effect on the rate of accumulation. The same irradiance dependence of this accumulation was observed in fruits, but a final decrease with senescence occurred in cucumber.CONCLUSION: This study demonstrates that the content of tocopherol in vegetables can be notably enhanced (or reduced) by simply selecting the appropriate harvesting time and/or by manipulating the environmental conditions during the growth period. Copyright