PHENOLIC CONTENT AND ANTIOXIDANT CAPACITIES OF
PARINARI CURATELIFOLIA, STRYCHNOS SPINOSA AND
ADANSONIA DIGITATA
L. NHUKARUME
1
, Z. CHIKWAMBI
1
, M. MUCHUWETI
1,3
and
B. CHIPURURA
2
1
University of Zimbabwe
Department of Biochemistry
Faculty of Science
Harare, Zimbabwe
2
Chinhoyi University of Technology
Department of Food Science and Post Harvest Technology
School of Agricultural Science
Chinhoyi, Zimbabwe
Accepted for Publication December 28, 2008
ABSTRACT
The phenolic content and antioxidant capacities of Parinari curatelifolia,
Strychnos spinosa and Adansonia digitata were determined and compared to
orange juice and baobab nectar, a commercial beverage. Methanolic extracts
were investigated for their ability to scavenge free radicals by the 1,
1-diphenyl-2 picrylhydrazyl radical and superoxide radical scavenging assays
whilst the b-Carotene Linoleic Acid Model System and inhibition of phosho-
lipid peroxidation were used as model systems. The reducing power assay was
used to determine the reducing potential of the extracts.
Results showed that the beverages in this investigation were capable of
acting as antioxidant sources as they displayed significant radical scavenging
properties. Adansonia digitata had the highest and comparable antioxidant
activities to Citrus sinensis (orange). The total phenolic, ascorbic acid, proan-
tocyanidin and flavonoid contents ranged between 12 and 58 mg GAE/
100 mL, 0.00 to 51.26 mg/100 mL, 0.35–1.071% and 18.3–124 mg/100 mL,
respectively. There was a positive correlation between antioxidant activities
and phenolic compounds content but there was no clear relationship between
proanthocyanidin content and antioxidant activity.
3
Corresponding author. TEL: 00263-0-4-308047; FAX: 00263-4-308046; EMAIL: muchuweti@
medic.uz.ac.zw
DOI: 10.1111/j.1745-4514.2009.00325.x
Journal of Food Biochemistry 34 (2010) 207–221.
© 2010, Wiley Periodicals, Inc. 207