Vegetables World : Spinach

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The origin of spinach (Spinacia oleracea L.) has been placed near Iran where it has been cultivated for at least 2000 years. Its cultivation in North Africa and Europe began about 1000 A.D. Related wild types are S. tetranda, a possible ancestor, and S. turkestanica. Spinach is an annual plant grown in temperate regions exclusively for its leaves. The spinach root system consists ofmany shallow fibrous laterals developing from a slightly thickened taproot, with few large laterals. Soon after the seedling stage, plants assume a rosette growth habit with many fleshy leaves attached to a short stem. Spacing and environmental conditions influence leaf number and size. Leaf blades range from ovate or nearly triangular to long and narrow arrowhead shapes, the latter is a characteristic of primitive types. Leaf margins are smooth or wavy and surfaces are smooth, semi savoy to heavily savoyed. (Rubatzky and Yamaguchi, 1997).

Spinach is an extremely nutritious vegetable, rich both in core nutrients and phytochemicals. The major micronutrients in spinach are vitamins A (from β-carotene), C, K and folate, and the minerals, calcium, iron and potassium. Spinach also provides fibre and is low in calories. The phytochemicals of most importance are the carotenoids, β-carotene, lutein and zeaxanthin and phenolic compounds. A number of studies have shown spinach to have strong antioxidant activity and high levels of antioxidant compounds such as phenolics and carotenoids. Antioxidant activity is important as many chronic diseases and health issues associated with ageing are believed to result from excessive oxidative stress. One of the major health benefits attributed to two major compounds in spinach, lutein and zeaxanthin, is that of protecting against eye diseases such as macular degeneration (gradual loss of central vision, associated with old age). Epidemiological and laboratory studies have also shown that spinach, spinach extracts, and spinach compounds may delay or retard agerelated loss of brain function, reduce the extent of post-ischaemic stroke damage to the brain, and protect against cancer through various different mechanisms (Hedges and Lester, 2007).