Antioxidants, proteins, and carotenoids in potato (Solanum tuberosum L.) /
Recent studies show that antioxidants benefit the human diet. Therefore, the total antioxidant content of important commercial U.S. potato varieties was investigated, as well as skin influence on th1 activity, the relative levels of antioxidant compounds, and total protein content. Patatin localizat...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
2000.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=731980601&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Recent studies show that antioxidants benefit the human diet. Therefore, the total antioxidant content of important commercial U.S. potato varieties was investigated, as well as skin influence on th1 activity, the relative levels of antioxidant compounds, and total protein content. Patatin localization and its role as an antioxidant were also investigated. Finally, the effects of growing location on total carotenoids, carotenoid levels, and color intensity, and the effects of environment on flesh color were determined. Significant differences in total protein content were found among the varieties studied. The results of enzyme activity in boiled and dialyzed versus boiled and not-dialyzed samples indicated that palate Ls not involved in antioxidant activity. Patatin is most concentrated in the outer medulla or perimedullary zones toward the stem end; it is completely absent in the cortex, pith rays, inner medulla, and branches to the eyes or buds. Significant differences in total antioxidant activity between varieties, extraction media, and variety x extraction media interactions were found in all varieties grown in Idaho. The water extraction method, considered inexpensive and safe, recovered most compounds contributing to antioxidant activity. Although the skin contributes to antioxidant activity, it is insignificant on a whole-tutor basis. Potato varieties differ in levels of such antioxidant compounds as caffeic acid, chlorogenic acid, frolic acid, protocatechuic acid, trytophan, tyrosine, and vanillic acid. The highest levels of the most abundant antioxidant compounds, chlorogenic acid, trytophan, and tyrosine, occur respectively in the following varieties: Russet Burbank, Russet Norkotah, Viking, Shepody, and Yukon Gold. Texas-grown varieties had higher lutein, lutein-epoxide, violaxanthin, zeaxanthin, and total carotenoid content than Colorado-grown varieties. However, these compounds were highly affected by location, variety, locations. Color measurements for lightness, chroma, and hue angle showed that Texas-grown varieties were darker than those grown in Colorado; thus, environment plays more of a role in color expression than does genetics. The study's most important findings were the high levels of water-soluble phenolic antioxidant and total antioxidant activity. Future research to examine the potato for non-water-soluble antioxidant content could lead to further enhancement of health and location x variety interaction in both benefits derived from potatoes. |
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| Item Description: | Vita. "Major Subject: Horticulture". |
| Physical Description: | xiii, 170 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 142-152). |