Flavonoid composition and antioxidant activity of pigmented sorghums of varying genotypes
| dc.contributor.advisor | Rooney, Lloyd W. | |
| dc.contributor.committeeMember | Cisneros-Zevallos, Luis | |
| dc.contributor.committeeMember | Rooney, William L. | |
| dc.contributor.committeeMember | Walzem, Rosemary L. | |
| dc.creator | Dykes, Linda | |
| dc.date.accessioned | 2010-01-15T00:02:34Z | |
| dc.date.accessioned | 2010-01-16T01:30:55Z | |
| dc.date.available | 2010-01-15T00:02:34Z | |
| dc.date.available | 2010-01-16T01:30:55Z | |
| dc.date.created | 2008-05 | |
| dc.date.issued | 2009-05-15 | |
| dc.description.abstract | A wide variety of sorghum genotypes with a pigmented pericarp were grown in varying environments and were analyzed for total phenols, condensed tannins, flavan-4-ols, and in vitro antioxidant activity. In addition, sorghum flavonoids were separated, characterized, and quantified using HPLC-PDA and LC-MS. Total phenols and in vitro antioxidant activity increased when sorghums had a pigmented testa causing the presence of condensed tannins. Flavan-4-ol levels were highest in sorghums with a black pericarp (5.8-16.1 abs/mL/g), followed by those with a red pericarp (1.1-9.2 abs/mL/g). Sorghums with a black pericarp had the highest 3-deoxyanthocyanin levels (308-1885 µg/g) and these were increased when the grain had minimal weathering and was darkest in color. Sorghums with a lemon-yellow pericarp had the highest flavanone levels (260-3586 µg/g) with eriodictyol being the main flavanone. Flavanone levels were increased when the grain was bright yellow with minimum weathering and were high compared to those found in common sources (238-574 µg/g, fresh wts.). No flavonoids were predominant in sorghums with a red pericarp. Flavonoid composition varied when all sorghums were grouped by secondary plant color. Sorghums with tan secondary plant color, including those with a white pericarp, had higher levels of flavones (50-932 µg/g) than those with red/purple secondary plant color (0-172 µg/g). On the other hand, 3-deoxyanthocyanin levels were higher in red/purple plant sorghums (14-1885 µg/g) than in tan plant sorghums (0-24 µg/g). Among red/purple plant sorghums, lemon-yellow pericarp sorghums had the highest levels of flavones (51-172 µg/g). Environment and weathering had an effect on flavonoid levels. The 3-deoxyanthocyanins were reduced for sorghums grown in a dry environment (i.e. Lubbock, TX) and flavonoid levels were increased in grains with minimum weathering or molding. This study reports that all sorghums, including those with a white pericarp, have flavonoids and their levels and compositions are affected by the genotype. This information will be helpful for plant breeders, food scientists, and the pharmaceutical/nutraceutical industries in selecting sorghums with desired healthy components. | en |
| dc.format.digitalOrigin | born digital | en |
| dc.format.medium | electronic | en |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | https://hdl.handle.net/1969.1/ETD-TAMU-3279 | |
| dc.language.iso | en_US | |
| dc.subject | Sorghum | en |
| dc.subject | Flavonoids | en |
| dc.subject | Antioxidants | en |
| dc.title | Flavonoid composition and antioxidant activity of pigmented sorghums of varying genotypes | en |
| dc.type | Book | en |
| dc.type | Thesis | en |
| dc.type.genre | Electronic Dissertation | en |
| dc.type.material | text | en |
| thesis.degree.department | Council of Deans | en |
| thesis.degree.discipline | Food Science and Technology | en |
| thesis.degree.grantor | Texas A&M University | en |
| thesis.degree.level | Doctoral | en |
| thesis.degree.name | Doctor of Philosophy | en |
Files
Original bundle
1 - 1 of 1