|
In-vitro assessment of antioxidant
potential and phenolic capacity of Temnocalyx obovatus
leaves
P. Dzomba*, E.
Togarepi and C. Mahamadi
Chemistry Department, Faculty of Science Education, P. Bag
1020, Bindura, Zimbabwe.
*Corresponding author. E-mail:
pdzomba@gmail.com or
pdzomba@buse.ac.zw. Tel: +263773474525. Fax: +263 7536.
Accepted 4 April, 2012 |
|
Temnocalyx obovatus
is widely found in many areas in Zimbabwe, Nigeria and
Zambia where it is used to treat a variety of ailments.
Phenolic compounds in T. obovatus assessed by
Folin-Ciocalteu method varied from 1.18 to 2.89 mg tannic
acid g-1. Acetone extract showed the greatest
flavonoids, flavonols and proanthocyanidins content 5.12,
4.13 and 3.07 mg catechin g-1 respectively. 2,
2-diphenyl-1-picrylhydrazyl radical (DPPH.)
scavenging effect, Ferric reducing ability and egg lipid
peroxidation inhibition assays were adopted to evaluate
antioxidant activity. Acetone extracts exhibited the
greatest antioxidant activity for all the assays, followed
by methanol extracts. Hexane extracts showed the weakest
activity. Correlation studies showed that antiradical
activity is explained more by flavonols and
proanthocyanidins (73%) and flavonoids (71%) and weakly by
phenolic contents (43%). The results revealed significant
phenolic capacity and antioxidant potential of T.
obovatus to warrant its use as a source of antioxidants.
It can be added to foods, such as, meat and soups for
enhancement of nutritional content and promotion of health.
Key words:
Antioxidant activity, phenolics, T. obovatus. |
