Progress 07/01/01 to 12/31/03
Outputs
C-FAR 2002 Internal. The level of S-methylmethionine (SMM) in corn gluten and soybean meals have been determined to be about 0.5 and 1.65 mg/g, respectively. In diets singly deficient in either methionine (Met) or choline (Cho), the addition of SMM produces a significant growth response in chicks. Thus, SMM in foods and feeds contain both Met and Cho sparing activiy.
Impacts
Met has to be supplemented to chick diets to obtain maximum growth rate. This is a costly supplementation. The fact that SMM has Met and Cho sparing activity in chick diets means that SMM could reduce the amount of Met and Cho presently added to poultry feeds if strains of corn and soy could be found or made that overproduce this compound.
Publications
- No publications reported this period
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Progress 01/01/02 to 12/31/02
Outputs
C-FAR 2002 Internal. We have made progress on the specific aims of this grant. Over the last year we have developed a method to prepare L-S-methylmethionine iodide (SMM-I). Using these preparations we have now developed an assay to specifically detect this compound in animal feed stuffs, overcoming earlier problems of contamination in commercial batches of SMM-I. We decided to delay the large scale quantification of SMM in plant materials until after we find out if it is efficacious as an Met-replacer in animal feeds. Over the last year we did a chick bioassay using SMM-I and Met as the variable dietary factors. An unanticipated outcome of this bioassay was that we discovered that iodide was toxic to the chicks at the levels fed in this study (isomolar to normal Met levels). Thus, our plan for the upcoming year is to devise a protocol to convert SMM-I to the chloride salt, and then redo the chick bioassay. After that, we will determine the levels of SMM in animal
feeds.
Impacts
If SMM can replace some or all of the dietary requirement for Met in swine and/or poulty feeds, then this compound may be overproduced and compete for the $500 million/year world-wide market for Met, most of which is sold as feed supplement. If so, enhancement of SMM production by plants will be desireable.
Publications
- No publications reported this period
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Progress 01/01/01 to 12/31/01
Outputs
C-FAR 2002 Internal. This project began July 2001 and has the following specific aims: 1. Synthesize enough L-S-methylmethionine (SMM) for feeding trials in poultry, and to use as a standard for the determination of SMM in feed stuffs. 2. Perform chick bioassays to determine the bioefficacy of L-SMM as a specific precursor for L-methionine and L-cysteine. To date we have worked to develop an assay to detect SMM in biological samples. The procedure under development employs conventional ion-exchange chromatography with nihydrin detection. Using the only commercially source of the compound available (the D,L-form), our amino acid analysis indicates that this commercial preparation are far from pure. We estimate that up to 10% of this commercially available preparation is methionine, and two other compounds of unknown identity represent another 10% of this product. Thus, we are currently developing an ion exchange procedure to remove these contaminants and we have now
isolated greatly enriched SMM and determined its retention time in our amino acid analyzer. Our plan of work for the next 1.5 years includes characterizing the level of SMM in animal feed stuffs from various sources. We also plan to initiate feeding trials with chicks to determine the efficacy of SMM as a replacement for dietary methionine and cysteine. Prior to the animal studies, we have to develop a large scale synthesis of L-SMM from L-methionine.
Impacts
If SMM can replace some or all of the dietary requirement for Met in swine and poultry feeds, then this compound may be overproduced and compete for the 500 million/year world-wide market for Met, most of which is sold as a supplement for swine and poultry feeds. If so, enhancement of SMM production by plants will be desirable.
Publications
- No publications reported this period
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