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The antioxidant properties of methanolic extracts from soybean obtained with germination, wounding, and application of biotic elicitors were evaluated. Also, the relationship between observed antioxidant properties and compositional changes in isoflavone content was determined. The 2 biotic elicitors used in this study were the food-grade fungus Aspergillus sojae and A. sojae cell wall extract. Isoflavone content was determined by C18 reverse phase high-performance chromatography coupled with a photodiode array detector. Antioxidant activities of the extracts were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and β-carotene cooxidation in a linoleate system. Higher antioxidant activities were observed in wounded and elicitor-treated extracts when compared with nonwounded control extracts. In addition, the phenolic content was higher in extracts from wounded and elicitor-treated soybean. Germination for 3 d slightly decreased total isoflavone content (–4.3%); however, wounding increased total isoflavone content (25.8%). The soybean extracts from seeds treated with A. sojae biotic elicitors had the highest total isoflavone contents (9.8 to 11.6 mg/g extract) and displayed the highest antioxidant activities in both the DPPH and β-carotene assays. Also identified in the wounded and elicitor-treated extracts were the induced isoflavones glyceollins that contributed to the higher isoflavone contents observed. [ABSTRACT FROM AUTHOR]

Gluten-free pancakes were prepared using rice flour and rice flour replaced with various amounts, at 10, 20 and 40%, of sweet potato flour. Textural properties of the cooked pancakes, such as hardness and chewiness generally increased with time after cooking, whereas they decreased with increased sweet potato flour replacement. On the other hand, cohesiveness decreased with time, but increased with increased sweet potato flour in the pancake. Nutritional properties of the rice–sweet potato pancakes, such as protein content, dietary fiber, total carbohydrate and calories were generally comparable with those of their wheat counterpart. The only significant difference was in the beta-carotene content, which increased from 5.2 to 236.1 μ g/g when sweet potato flour was incorporated, from 0 to 40%, into the rice pancake formulation. [ABSTRACT FROM AUTHOR]

The Fusarium mycotoxin, 4-deoxynivalenol, is an abundant, natural contaminant of corn and wheat. 8-Oxo-12,13-epoxytrichothecenes related to 4-deoxynivalenol were synthesized; they either lacked the 7-hydroxyl but contained a hydroxyl at C-4 (7-deoxynivalenol) or lacked substituents at C-3 and C-7 (3,7-dideoxynivalenol). The ability of these synthetic analogs and their acetylated derivatives to inhibit protein synthesis by cultured mammalian cells was compared to that of 4-deoxynivalenol. Whereas the 50% inhibitory dose (ID50) for murine erythroleukemia cells was about 1 microgram/ml for 4-deoxynivalenol and 3,7-dideoxynivalenol, all of the other analogs were at least 10-fold less potent. When tested at their ID50 dose, all of the 8-oxotrichothecenes, except 4-deoxynivalenol and 3,7-dideoxynivalenol, caused polysome 'run-off', indicating that, at this dose, they are inhibitors of polypeptide chain initiation. With 4-deoxynivalenol and 3,7-dideoxynivalenol, polysomes remained at control levels indicating that these toxins prevent polypeptide chain elongation. From these results and comparisons to previous studies of 8-oxo-12,13-epoxytrichothecenes (trichothecolone, trichothecin, nivalenol and fusarenone X), trichothecenes with substituents at both C-3 and C-4 predominantly inhibit polypeptide chain initiation, whereas those lacking one substituent at either site are inhibitors of chain elongation.