• Food Science and Biotechnology
• /
• v.14 no.2
• /
• pp.177-180
• /
• 2005

Antioxidant activity of crude extracts from colored sweet potato cultivars by plant parts such as root, stem and leaf was evaluated. The highest TBARS values were obtained from root samples of sweet patato, and followed by stems and leaves, indicating that leaf sample showed the strongest antioxidant activity. Sweet potato cultivars with yellow flesh and leaf part exhibited strong antioxidant activities. Antioxidant activities of leaf and stem extracts were maintained for 21 days and were a little lower than that of BHT. The DPPH radical scavenging activity was the highest in "Sinhwangmi" leaf, and followed by "Jami" root. Chlorogenic acid was detected as the most abundant antioxidant substance among all fractions. These results suggest that the antioxidant activity of sweet potato differs depending on plant part and cultivar.

• Korean Journal of Food Science and Technology
• /
• v.29 no.2
• /
• pp.218-222
• /
• 1997

Twelve varieties of yellow sweet potatoes were measured for carotenoids content to assess their potential as a source of natural food colorant. Benihayato variety had the highest content of carotenoids (20.2 mg/100 g fr wt) but other varieties ranged with $4.6{\sim}16.7\;mg/100\;g$ fr wt. Hunter's +a-values (redness) increased linearly $(R^{2}=0.826)$ with carotenoids content of yellow sweet potatoes. Absorption spectrum of carotenoids extracted from the Benihayato variety was similar to that of standard ${\beta}-carotene$ indicating that carotenoids in yellow sweet potato are mostly composed of ${\beta}-carotene$.