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Title: MONITORING SUGAR METABOLISM IN SWEET CORN USING INDIRECT PHOTOMETRIC DETECTION AND CAPILLARY ELECTROPHORESIS

Author
item Riner, L.
item Smith, J.t.
item Russo, Vincent

Submitted to: Research Day Abstracts: Regional Universities Research Day
Publication Type: Abstract Only
Publication Acceptance Date: 12/10/2000
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Many new varieties of high yield sweet corn suffer from extremely germination yields. The low yield is believed to be attributed to a low starch content in the endosperm of the kernel. A method was developed for the analysis of starch content in sweet corn tissue at various stages of plant development using capillary electrophoresis (CE). A simple extraction method was developed to extract the sugars from freeze-dried tissue samples. The protocol required that the simple sugars be removed in an ethanol extract leaving the complex carbohydrates. The water soluble polysaccharides were extracted using ice water leaving the starch fraction. The starch component was then hydrolyzed using HCl to yield the simple sugar. Glucose was then quantified to correlate back to the original amount of starch in the sample. The capillary electrophoresis method developed elutes glucose in less than 8 minutes without interference from the sample matrix. Since glucose has little absorbance in the UV region, indirect photometric detection was employed for quantification. Sorbic acid and 2,6-naphthalene-dicarboxylic acid were examined as potential background chromophores for indirect detection. The best separation and detection was obtained using a commercially available buffer system from Hewlett Packard. The method was characterized in terms of the limit of detection and its working range. More than 40 tissue samples were analyzed for starch using this method.