Template for Electronic Submission of Organic Letters

Antioxidant Capacity and Total Phenolic Content (DPPH and ORAC) of
Senegalia polyphylla.
1
2
3
1*
Daré, R.G. ; Romagnolo, M.B. ; Visentainer, J.V. ; Truiti, M.C.T. .
[email protected]
1
Laboratório de Fitoquímica e Desenvolvimento de Produtos Tópicos – Programa de Pós-graduação em Ciências
Farmacêuticas - Universidade Estadual de Maringá – UEM – Av. Colombo, 5790, Jd. Universitário – Maringá – PR –
2
Brasil. Laboratório de Sistemática Vegetal – Departamento de Biologia – Universidade Estadual de Maringá – UEM –
3
Av. Colombo, 5790, Jd. Universitário – Maringá – PR –Brasil. Laboratório de Analítica Aplicada a Lipídios, Esteróis e
Antioxidantes – Departamento de Química – Universidade Estadual de Maringá – UEM – Av. Colombo, 5790, Jd.
Universitário – Maringá – PR –Brasil.
Keywords: Fabaceae, polyphenols, DPPH, ORAC.
Introduction
Polyphenols are secondary metabolites produced
in plants that have become a focus of increased
research interest due to the different biological
properties that they present, including antioxidant
activity. These natural antioxidants are beneficial to
the human body because they help to combat a
situation of overload of reactive oxygen species
1
(ROS), consequently the oxidative damages .
This study aimed to evaluate the total phenolic
content (TP) and the antioxidant potential of
Senegalia polyphylla (DC.) Britton & Rose
(Fabaceae) leaves. The antioxidant capacity of
ethanol extract (EE) obtained by percolation, and its
hexane (HF), ethyl acetate (AF) and hydromethanol
(MF) fractions obtained by liquid-liquid partition was
evaluated
using
1,1-diphenyl-2-picrylhydrazyl
(DPPH) and oxygen radical absorbance capacity
(ORAC) methods, and TP by a colorimetric method
2,3,4
using the Folin-Ciocalteu reagent .
Results and Discussion
The results obtained are shown in Table 1.
Table 1. Antioxidant capacity and total phenolic
content (TP) of ethanol extract (EE), hexane (HF),
ethyl acetate (AF) and hydromethanol (MF)
fractions from leaves of Senegalia polyphylla
and quercetin (QT).
Sample
EE
HF
AF
MF
QT
TP
(mg GAE/g
sample)
DPPH
(µg/mL)
415.6 ± 12.3
nd
317.9 ± 14.2
221.8 ± 8.6
---------
20.6 ± 0,2
91.1 ± 0.4
12.6 ± 0,3
21.8 ± 0.6
2.9 ± 0,01
ORAC
(μmol TE/g sample)
(317.9 ± 14.2 mg GAE/g sample) and MF (221.8 ±
8.6 mg GAE/g sample).
The DPPH method evaluates the capacity of the
compounds act as donor of hydrogen and/or
electrons to the radical DPPH and the ORAC
method indicates the ability of an antioxidant to block
the peroxyl radical, mimicking the prevention of lipid
5
peroxidation in vivo . Among the samples evaluated
here, AF and MF also presented the best results
regarding antioxidant capacity in both methods used.
The results obtained suggest that the phenolic
compounds contribute to the observed antioxidant
activity.
The extract and its fractions present a complex
composition, with many chemical constituents,
justifying a higher activity verified to quercetin, a pure
compound, used as standard antioxidant.
Conclusions
Based on the results obtained, raw materials
obtained from S. polyphylla leaves can be seen as
an important source of natural antioxidants.
Therefore, additional phytochemical studies of S.
polyphylla are being conducted in order to isolate
and identify its main constituents.
Acknowledgements
Programa de Pós-graduação em Ciências
Farmacêuticas, Universidade Estadual de Maringá
and Coordenação de Aperfeiçoamento de Pessoal
de Nível Superior (CAPES).
____________________
1
1276,16 ± 13,60
799.3 ± 72.5
12738.9 ±1080.1
4667.7± 398.1
2693.3±1775.2
The values refer to the average of three determinations ±
standard deviation. GAE= gallic acid equivalents. TE=
Trolox equivalent. nd = not detected.
The higher TP is found in the EE (415.6 ± 12.3 mg
GAE/g sample), followed by the polar fractions, AF
Melo, E.A., Maciel, M.I.S., Lima, V.L.A.G, Araújo, C.R. Alim.
Nutr., 2008; 19(1): 67-72.
2
El-Massry, K.F., El-Ghorab, A.H., Farouk, A. Food Chemistry,
2002; 79: 331-336.
3
Benzie, I.F.F., Strain, J.J. Analytical Biochemistry, 1996; 70:
239.
4
Singleton, V.L.,Orthofer, R., Lamuela-Raventos, R.M. Methods
of Enzymology, 1999; 299:152-178.
5
Sucupira, N.R., Silva, A.B., Pereira, G., Costa, J.N. Cient. Ciênc.
Biol. Saúde, 2012;14(4):263-269.