Purple sweet potato tuber extract lowers mallondialdehyde and improves glycemic control in subjects with type 2 diabetes mellitus

Oxidative stress and chronic hyperglycemia are related to progressivity of type 2 diabetes mellitus (T2DM). Purple sweet potato tuber possesses high anthocyanin (ANT) antioxidant. The objective of this study is to prove that supplementation of purple sweet potato tuber extract can lowers mallondialdehyde (MDA) and improves glycemic control in T2DM subjects. A randomized double blinded pre-post tests controlled group design study enrolling 38 T2DM subjects was conducted at Diabetes Outpatients Clinic, Sanglah Hospital for 4 weeks observation. Subjects were divided into 2 groups: the Control Group (placebo) and the group who were given 75 mL purple sweet potato tuber extract containing 11 gram ANT (ANT Group), 3 times a day 30 minutes after meal. All subjects were treated with standard diabetic care. One subject of each group was dropped out from this study, therefore each group finally consisted of 18 subjects; male-female ratio was 9/9 among Control Group and 8/10 among ANT Group; average of age was 51.94±5.01 years and 51.78±4.97 years, respectively. Levels of MDA was found significantly lower in ANT Group than in that of Control Group after administration (0.43±0.08 vs. 0.52±0.15 ?M, p=0,04). Decreased (the difference between post- and pre-test [?]) MDA levels in ANT Group was higher compared to that in Control Group (0.1250.12 vs. -0.030.15 ?M, p=0.002). Improvement of fasting and 2 hours post-prandial (2hpp) plasma glucose levels in ANT Group started at week 1 and continued till week 4. Improved fasting and 2hpp plasma glucose (?) in the ANT Group was better than among Control Group (67.167 vs. -1.83 mg/dl, p<0.001; 72.11 vs. -15.4 mg/dl, p=<0,001; respectively). Improved glycated albumin (?) was also found significantly among subjects in the ANT Group than those in the Control Group (24.13±5.86 vs. 26.18±8.1 %, p=0,049). Purple sweet potato tuber extract administration could lower MDA levels and improved glycemic control (decreased fasting and 2hpp plasma glucose levels and glycated albumin) in subjects with T2DM. Keywords: purple potato tuber extract, malondialdehyde, glycemic control. INTRODUCTION Currently diabetes (especially type 2 diabetes mellitus [T2DM]) has become pandemic and it is a serious health *Corresponding