TITLE:
Phytochemical Screening, Total Phenolic and Antioxidant Activity of Numerous Extracts from Leaves and Bark of Bauhinia rufescens Lam
AUTHORS:
Seid Ali Mahamat, Niang Lahat, Ayessou Nicolas Cyrille, Cisse Mady, Diop Codou Mar
KEYWORDS:
Bauhinia rufescens Lam, Total Phenolic, Antioxidant Activity
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.12 No.6,
June
21,
2021
ABSTRACT: Researches for natural antioxidants that play an important role in the
prevention of diseases linked to free radicals have increased in recent years. In this study,
antioxidant activity of Bauhinia rufescens Lam which is a medicinal
plant was investigated. The
methanol extract, acetone extract and water extract of leaf and trunk bark had
antioxidant activity. Three methods were used: 2,2-diphenyl-1picryl-hydrazyl
(DPPH), 2,2’-Azino-bis-(3-ethylbenzoth iazoline-6-sulfonic acid)
(ABTS) and ferric ion reducing power (FRAP) by spectrophotometry. Phytochemical screening
was carried out followed by the quantification of the total phenolic by the
Folin-Ciocalteu method. The analysis of variance (ANOVA) with the STATISTICA
7.1 software revealed significant differences (p 0.05). Percentage inhibition (PI) and IC50 of the extracts were obtained using the OriginPro 8.5 software. These
tests show that the bark is as rich in total phenolic as the leaves. The DPPH
test shows that at 2.5 mg/ml, the bark and the leave have similar activity.
Bark has a percentage inhibition (PI) of 86.55% ± 0.026% compared to the leave
which PI is 85.63% ± 0.02%. As for the ABTS test, the bark extract reached its maximum activity
at 2.5 mg/ml with a PI of 99.81% ± 0.012% compared to the leaf extract which
has a PI of 99.61% ± 0.025%. The best IC50 of the
extracts obtained with the DPPH radical is 0.139 ± 0.001 mg/ml (hydro-acetonic), 0.354 ± 0.001 mg/ml
(hydromethanolic) and 0.840 ± 0.001 mg/ml (aqueous) on the bark. With ABTS
test, it was obtained 0.351 ± 0.001 mg/ml (hydro-acetone; bark), 0.403 ± 0.001
mg/ml (hydro-acetone; leaves) and 0.474 ± 0.001 mg/ml (aqueous; bark). The
reducing power of the leaves is slightly higher than that of the bark. Standard
of ascorbic acid, has a PI of 94.86 ± 0.008% with an IC50 of 0.213 ±
0.001 mg/ml. Thus, it is easy to conclude that the bark of Bauhinia rufescens has a better activity than
the leaves and the alcoholic extracts have given better results than the
aqueous extract.