Evaluation of Physicochemical Properties and Antioxidant Activity of Wheat-Red Kidney Bean Biscuits

This research was aimed to study the physicochemical properties and antioxidant activity of biscuits fortified with red kidney bean (Phaseolus vulgaris) powder. Proximate compositions, total phenol content, antioxidant activity, and functional properties of red kidney bean (RKB) powder were studied before and after the incorporation of red kidney bean in the biscuits. The bean powder was mixed with wheat flour at a level of 0% as control, 10%, 20%, and 30% during dough preparation. Results revealed that RKB powder is a rich source of protein (26.25%) together with carbohydrate (59.7%), fat (2.4%), and ash (3.27%). The total phenolic content of bean powder was 14.15 mg GAE/g. Kidney bean powder showed good functional properties including water absorption capacity (149.7%), oil holding capacity (99.54%), swelling capacity (4.6%), and bulk density of 0.74 g/ml. After increasing the percentage of RKB with control, there were significant increases (p < 0.05) in the levels of protein, moisture, ash, fat, while carbohydrate content and total gross energy decreased significantly. Investigation of total phenolic content showed the increasing trend with the higher RKB fortification, which amounted to 10.31 mg GAE/g for control and 12.50 mg GAE/g for 30% RKB. DPPH radical scavenging activity was investigated for all the samples at five different concentrations. As there was an increase in the percentage of RKB and concentration of the samples, the antioxidant activity also increased significantly (p < 0.05), where IC50 value decreased from 0.0228 mg/ml for control to 0.0289 mg/ml for 10% RKB, followed by 20% and 30% RKB, respectively. In sensory test, the control cake secured the highest score in color, flavor, texture and overall acceptability followed by the cake incorporated with 10% freeze-dried mushroom powder.

Effects of Enhanced UV-B Radiation on the Activity and Expression of Alternative Oxidase in Red Kidney Bean Leaves

An increase in ultraviolet （UV） B radiation on the earth＇s surface is a feature of current global climate changes. It has been reported that alternative oxidase （AOX） may have a protective role against oxidative stress induced by environmental stresses, such as UV-B. To better understand the characteristic tolerance of plants to UV-B radiation, the effects of enhanced UV-B radiation on the activity and expression of AOX in red kidney bean （Phaseolus vulgaris） leaves were investigated in the present study. The results show that the total respiration rate and AOX activity in red kidney bean leaves increased significantly during treatment with enhanced UV-B. However, cytochrome oxidase （COX） activity did not change significantly. The H2O2 content was also markedly increased and reached a maximum of 4.45 mmol·L^-1·g^-1 DW （dry weight） at 24 h of UV-B treatment, before dropping rapidly. Both alternative pathway content and alternative pathway activity were increased in the presence of exogenous H2O2. Immunoblotting analysis with anti-AOX monoclonal antibody revealed that expression of the AOX protein increased in red kidney bean leaves under enhanced UV-B radiation, reaching a peak at 72 h. In addition, AOX expression in red kidney bean leaves was induced by exogenous H2O2. These data indicate that the increase in AOX activity in red kidney bean leaves under enhanced UV-B radiation was mainly due to H2O2-induced AOX expression.

Response of Four Dry Bean Market Classes to Pre-Emergence Applications of Pyroxasulfone, Sulfentrazone and Pyroxasulfone plus Sulfentrazone

Only one herbicide mode of action (ALS inhibitor) is currently available to Ontario dry bean producers for soil-applied broadleaf weed control. Four field studies were conducted over two years (2014, 2015) to examine the tolerance of four market classes of dry beans to sulfentrazone (210 and 420 g·ai·ha-1) and pyroxasulfone (100 and 200 g·ai·ha-1) applied alone and in combination. The registration of these two herbicides would provide Ontario dry bean producers with two additional modes of action for broadleaf weed control. Pyroxasulfone caused up to 23%, 6%, 7% and 10% injury in adzuki, kidney, small red Mexican and white bean, respectively;sulfentrazone caused up to 51%, 12%, 15% and 44% injury and the combination caused up to 90%, 23%, 29% and 62% injury, respectively. Kidney and small red Mexican bean density, height, seed moisture content and yield were not affected. Pyroxasulfone (200 g·ai·ha-1) + sulfentrazone (420 g·ai·ha-1) reduced adzuki and white bean density, shoot dry weight, height and yield. This study concludes that pyroxasulfone (100 g·ai·ha-1) + sulfentrazone (210 g·ai·ha-1) applied PRE can be safely used to control weeds in Ontario kidney and small red Mexican bean production.