Accessible Requires Authentication Published by De Gruyter November 24, 2012

Diethylnitrosamine-induced redox imbalance in rat microsomes: protective role of polyphenolic-rich extract from Sorghum bicolor grains

Taofeek Olakunle Ajiboye, Yesirat Omonike Komolafe, Hussein Oyelola Bukoye Oloyede, Musa Toyin Yakubu, Moriam Dasola Adeoye, Ibrahim Olasegun Abdulsalami, Adenike Temidayo Oladiji and Musbau Adewumi Akanji


Background: This study investigates the protective role of polyphenolic-rich extract from Sorghum bicolor against diethylnitrosamine (DEN)-induced redox imbalance in rat microsomes.

Methods: Reactive oxygen species (ROS) scavenging potentials of the polyphenolic extract from S. bicolor (0.2–1.0 mg/mL) was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, hydroxyl radical, and ferric ion reducing system. The detoxification of ROS was evaluated in DEN-induced redox imbalance in rat microsomes.

Results: Sorghum bicolor polyphenolic extract at 1.0 mg/mL scavenged the DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical at 75%, 76%, 79%, and 81%, respectively; it also reduced ferric ion significantly. The polyphenolic extract significantly (p<0.05) attenuated DEN-mediated decrease in the activities of ROS detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase and reductase, and glucose-6-phosphate dehydrogenase). The concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxide, protein carbonyl, and percentage DNA fragmentation in DEN-treated microsomes were significantly reduced by the polyphenolic extract.

Conclusions: The results of the present study indicated that S. bicolor polyphenolic extract possessed in vitro antioxidant activity and protected microsomes from DEN-mediated oxidative stress by scavenging free radicals and ROS scavenger and inducer of ROS detoxifying enzymes.

Corresponding author: Taofeek Olakunle Ajiboye, PhD, Antioxidants, Free Radicals and Toxicology Research Laboratory, Biochemistry and Nutrition Unit, Department of Chemical Sciences, Fountain University, Osogbo, Nigeria

Received: 2012-7-11
Accepted: 2012-10-16
Published Online: 2012-11-24
Published in Print: 2013-02-01

©2013 by Walter de Gruyter Berlin Boston