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Leaf vegetables, also called potherbs, greens, vegetable greens, leafy greens or salad greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Although they come from a very wide variety of plants, most share a great deal with other leaf vegetables in nutrition and cooking methods. Nearly one thousand species of plants with edible leaves are known. Leaf vegetables most often come from short-lived herbaceous plants such as lettuce and spinach. Woody plants whose leaves can be eaten as leaf vegetables include ''Adansonia'', ''Aralia'', ''Moringa'', ''Morus'', and ''Toona'' species. The leaves of many fodder crops are also edible for humans, but usually only eaten under famine conditions. Examples include alfalfa, clover, and most grasses, including wheat and barley. These plants are often much more prolific than more traditional leaf vegetables, but exploitation of their rich nutrition is difficult, primarily because of their high fiber content. This obstacle can be overcome by further processing such as drying and grinding into powder or pulping and pressing for juice. Leaf vegetables contain many typical plant nutrients, but since they are photosynthetic tissues, their vitamin K levels in relation to those of other fruits and vegetables, as well as other types of foods, is particularly notable. The reason is that phylloquinone, the most common form of the vitamin, is directly involved in photosynthesis. This causes leaf vegetables to be the primary food class that interacts significantly with the anticoagulant pharmaceutical warfarin. During the first half of the 20th century, it was common for greengrocers to carry small bunches of herbs tied with a string to small green and red peppers; these bundles were called "potherbs." Image:Starr 020803-0094 Centella asiatica.jpg|Fresh Gotukola (Centella asiatica) Image:Swiss Chard.jpg|Fresh Swiss chard Image:Ong choy water spinach.png|Fresh water spinach Image:Կանաչի 3.JPG|Sabzi Khordan, an Iranian salad-like dish. ==Nutrition== Leaf vegetables are typically low in calories and fat, and high in protein per calorie, dietary fiber, vitamin C, pro-vitamin A carotenoids, folate, manganese and vitamin K. The vitamin K content of leaf vegetables is particularly high, since these are photosynthetic tissues and phylloquinone is involved in photosynthesis. Accordingly, users of vitamin K antagonist medications, such as warfarin, must take special care to limit consumption of leaf vegetables. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Leaf vegetable」の詳細全文を読む スポンサード リンク
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