Text: All forms of selenium may not be equally advantageous... http://www.nucycletherapy.com/minerals/selenium/brassica.htm Se-methylselenocysteine [CH3SeCH2CH - (NH2)COOH] is considered superior to either selenite or selenomethionine in cancer protection. This protection may be related to the rapid conversion of Se-methylselenocysteine to methylselenol, which can act as the signal in events associated with the suppression of neoplastic development. Chemical form of plant selenium In the late eighteen hundreds biologists first noted the similarity between sulfur and selenium. For example in 1880 C. A. Cameron wrote, "the analogy between sulphur and selenium suggests that selenium may wholly or partly replace sulphur as a constituent of vegetables" (Cameron 1880). In the following years Cameron's statement has been confirmed and it is now widely accepted that Se is able to substitute for sulfur in both cysteine and methionine forming selenocysteine and selenomethionine (for review see Brown and Shrift, 1982). Incorporation of these selenoamino acids into proteins is the major cause of selenium toxicity in plants. Interestingly, certain specialized Se accumulating plants appear to avoid these toxic effects by funneling Se into the non protein amino acids Se-methylselenocysteine and selenocystathionine (Brown and Shrift, 1982). Delivery of methylselenocysteine Research in selenium enrichment of foodstuffs was pioneered by Clement Ip, Donald Lisk, H.J. Thompson and coworkers with garlic (Ip and Lisk 1993, 1994a, 1994b, 1996; Ip et al. 1992,1994, 1996; Stoewsand et al. 1989). The normal concentration of selenium in fruits and vegetables and grain are in the 0.01 to 0.07 ppm range. These researchers were routinely able to grow garlic using selenate and selenite as fertilizers with yielding garlic 150 up to 1355 PPM selenium (Ip et al. 1992; Ip and Lisk 1995). The major source of selenium present in the selenium-enriched garlic as well as broccoli was determined to be MSC (Block 1996; Ge et al. 1996) and that it functions in the same manner as chemically synthesized MSC. Selenium supplied as selenium-enriched garlic at 2 ppm in the diet of rats was able to restore maximal activities of the two key selenoenzymes, glutathione peroxidase and type I 5'-deiodinase more effectively than selenite as the selenium source (Ip and Lisk 1993). Regards, Wayne Jr 07/27/04

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