Evaluation of Some Nigerian Savannah Plants for Antioxidant Activity, and Total Phenolic and Flavonoid Contents

Edewor, Theresa and Oluyori, Abimbola (2015) Evaluation of Some Nigerian Savannah Plants for Antioxidant Activity, and Total Phenolic and Flavonoid Contents. Evaluation of Some Nigerian Savannah Plants for Antioxidant Activity, and Total Phenolic and Flavonoid Contents, 34 (2). pp. 75-81. ISSN ISSN 0976 – 044X

[img] Text
Paper III edewor and peter.pdf - Published Version
Available under License Creative Commons Attribution No Derivatives.

Download (306kB)
Official URL: http://globalresearchonline.net/journalcontents/v3...

Abstract

The plant leaves of Nauclea diderrichii (Merr) (ND), Crossopteryx febrifuga (Afzel) Benth (CF), Lannea kerstingii Engl. and K. Krause (LK), Uapaca guineensis (UG) and Terminalia macroptera (TM) which were obtained from the savannah region in Nigeria were evaluated for antioxidant property and total phenolic and flavonoid contents. The plants leaves were extracted with non polar and polar solvents. The extracts obtained were analyzed for the presence or absence of certain phytochemicals. DPPH radical was used as an in-vitro model for evaluating the antioxidant activity of the methanolic extracts. Spectrophotometric methods were used to determine both total phenolic and flavonoid contents. TLC analysis was carried out to identify and quantify individual flavonoids using specific standard flavonoids as control. Phytochemical screening of the plants leaves gave the following: ND and LK gave positive test for tannins, flavonoids and saponins while steroids, alkaloids, terpenoids, cardiac glycosides and anthraquinone glycosides were negative for the methanolic extracts; all phytochemicals screened were absent in the n-hexane extracts. CF showed presence of flavonoids, saponins, steroids and cardiac glycosides while tannins, alkaloids, terpenoids and anthraquinone glycosides were absent in the methanol extract; all phytochemicals screened were absent in the n-hexane extract. The n-hexane extract of UG exhibited presence of steroids, alkaloids and terpenoids while flavonoids, saponins, cardiac and anthraquinone glycosides were observed to be absent. Its methanolic extract showed presence of steroids, alkaloids, terpenoids and cardiac glycosides while saponins, flavonoids, tannins and anthraquinone glycosides were absent. Only steroids were observed to be present in the n-hexane extract of TM. Tannins, flavonoids, saponins, steroids, terpenoids and cardiac glycosides were present in the methanolic extract while alkaloids and anthraquinone glycosides were absent. The plants leaves extracts gave the following total phenolic (mg GAE/mg extract) and flavonoid (mg quercetin equivalent/mg extract) contents and antioxidant activity respectively: ND 49.43±015, 73.00±0.03, 37.42±0.04; CF 63.71±0.02, 81.58±0.06, 48.23±0.03; LK 58.00±0.02, 56.08±0.03, 43.91±0.02; TM 64.29±0.02, 146.25±0.02, 48.67±0.05. UG did not possess polyphenolics and flavonoids so did not exhibit any antioxidant activity. In the flavonoid distribution TM had the highest number of flavonoid types and percent type present (20.94%, kaempferol) while LK had the lowest percent type (2.78%, myricetin). The leaves of these plants can serve as source of bioactive compounds and antioxidant agents. Only UG possessed neither polyphenolic nor flavonoid compounds. Keywords: Polyphenolics, flavonoids, antioxidants, leaves, savannah plants, Nigeria.

Item Type: Article
Subjects: Q Science > QD Chemistry
Divisions: Faculty of Engineering, Science and Mathematics > School of Chemistry
Depositing User: ABIMBOLA OLUYORI
Date Deposited: 28 Jun 2017 14:13
Last Modified: 28 Jun 2017 14:13
URI: http://eprints.lmu.edu.ng/id/eprint/453

Actions (login required)

View Item View Item