Purslane (Portulaca oleracea L. Portulacaceae) is an herbaceous annual with fleshy succulent leaves. It is a potherb native of the Asian subcontinent. Purslane is reported in the literature as a weed, a common potherb, and an unusual medicinal herb. In his book Walden Pond (1854), Thoreau mentioned that he made a "satisfactory dinner of a dish of purslane," that he gathered and boiled.

Purslane is a commercially cultivated vegetable in many parts of the world including Asia and the Middle East (1). Purslane is used as a vegetable in southern Europe, Mediterranean countries, and Asia. It is palatable, has a mild flavor and a mucilaginous quality. In the United States, it is grown as a specialty vegetable and available as mesclun salad in health food stores. Tender stems and leaves can be eaten raw, cooked, or pickled. The leaves of purslane can be frozen or dried and stored in jars for year-round usage.

Purslane grows well at day/night temperatures of 270C /220C and long days (~16 hours). Because of its high tolerance for different light intensities, temperature ranges and soil types, purslane can be grown in home gardens to provide a steady supply of greens for the kitchen. Seeds of two cultivated varieties (green leaf and golden) are available from Johnny's selected seeds, (Albion, ME). They are erect in their growth habit and produce larger leaves than the wild type that is prostrate and have smaller leaves.

Recently, purslane has attracted the attention of a number of biomedical, nutritional and agricultural researchers (2-4) as a potential addition to the Western diet, because of its high concentration of the essential fatty acids- linoleic (LA) and alpha-linolenic acids (a-LNA).

One hundred grams of fresh purslane leaves (~one serving or one 8 oz cup) can supply up to 300-400 mg of a-LNA, 12.2 mg of alpha-tocopherol, 26.6 mg of ascorbic acid, 1.9 mg of beta-carotene, and 14.8 mg of glutathione (5). Purslane is also an excellent source of essential amino acids (6) and nor-adrenaline (7). Because of its high nutritive and antioxidant properties, purslane is described as a "power food of the future" (8).

a-LNA concentration in purslane is the highest of any green leafy vegetable examined to date and reported as being higher than most commonly consumed fish (5, 9-10). Purslane appears to be the only higher plant reported to contain the beneficial omega-3 fatty acids (O3FAs)- eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA) (10, 11) which are precursors to a specific group of the prostaglandins.

Omega-3 fatty acids have antiarrhythmic, anti-inflammatory, antithrombotic, hypolipidemic, and vasodilatory properties, that are beneficial in hypertension, type-2 diabetes, coronary heart disease, and for patients with renal disease, rheumatoid arthritis, and ulcerative colitis (3).

The medicinal and health benefits of purslane are well documented in literature regarding its use in the treatment of burns and trauma; headaches; stomach, intestinal and liver ailments; cough; shortness of breath and arthritis, as a purgative, cardiac tonic, an emollient, a muscle relaxant, an anti-helminthic, an anti-inflammant, an anti-scorbutic, a cathartic, and a diuretic (5). Other potential uses of purslane include as an animal feed and in the food processing industry as a food extender and viscosifier.

References
1. Kays & Dias 1995. Common names of commercially cultivated vegetables of the world in 15 languages. Econ. Bot. 40 (2):115-152.
2. Adams 192. Purslane eyed as rich food source. Agricultural Research Ag. notes. December.
3. Simopoulos 1999. Essential fatty acids in health and chronic disease. Am. J. Clin. Nutr. 70(3 Suppl):560S-569S.
4. Palaniswamy 1998. Enhancement of naturally occurring chemopreventive compounds in salad greens through environmental manipulation during crop growth. Ph.D. dissertation, University of Connecticut.
5. Simopoulos et al. 1992. Common Purslane: A source of omega-3 fatty acids and antioxidants. J. Am. Col. Nutr. 11:374-382.
6. Miller et al. 1984. The agricultural potential of selected C4 plants in arid environment. J. Arid. Environ. 7:275-286.
7. Feng et al. 1961. High concentration of (-)-Noradrenaline in Portulaca oleraceae L. Nature 191:1108.
8. Levey 1993. The new power foods. Parade magazine. The Washington Post. Sunday Nov. 14 p.5.
9. Simopoulos & Salem Jr. 1986. Purslane: A terrestrial source of omega-3 fatty acids. N.Eng. J. Med. 315:833.
10. Simopoulos et al. 1986. Health effects of polyunsaturated fatty acids in seafoods, Proceedings from the conference, June 1985. Academic Press, Orlando, FL.
11. Omara-Alwala et al. 1991. Omega-three fatty acids in purslane (Portulaca oleracea) tissues. JAOCS. 68:198-199.

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