الفهرس 
Medicinal PlantsOnly 14 pages are availabe for public view
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Abstract
In the present study, extracts of different percentages of
methanol and water of Salix mucronata leaves were
prepared and evaluated as antioxidant agents using three
in-vitro techniques which are; DPPH radical scavenging
activity, ABTS/TEAC (Trolox-equivalent antioxidant
capacity( and Total antioxidant capacity
(Phosphomolybdenium assay). Also, their antimicrobial
activity was determined using disc diffusion assay
(DDA).
- Owing to the high activity of 85% methanolic extract,
the defatted 85% methanolic extract was submitted to
fractionation process using chloroform (CHCl3), ethyl
acetate (EtOAc) and n-butanol (n-BuOH). These
fractions were evaluated as antioxidant and
antimicrobial agents. The results revealed that the
EtOAc and n-BuOH fractions have high antioxidant and
antimicrobial activities.
- The total phenolic and flavonoid contents of 85%
methanolic extract and fractions derived from it were
also determined. The results revealed that there is a
positive correlation between the phenolic and flavonoid
contents and the antioxidant activity of the tested
extracts.
- Separation of certain chemical constituents from the
EtOAc and n-BuOH fractions derived from 85%
methanolic extract was achieved using different
chromatographic techniques.
- Identification and structure elucidation of the pure
isolated compounds were taken place by using different
spectroscopic analyses such as UV, 1H NMR and 13C
NMR as well as acid hydrolysis.
- Six compounds were isolated from the EtOAc fraction
derived from 85% methanolic extract of S. mucronata
leaves and their structures were identified as; apigenin
(1), quercetin (2), quercetrin (3), rhamnazin-3-O-β-Dglucopyranoside (4), chrysoeriol-7-O-β-D-glucuronoid-
6``-methyl ester (5) and tremuloidin (6).
- Five compounds were isolated from the n-BuOH
fraction derived from 85% methanolic extract of S.
mucronata leaves and their structures were elucidated
as; kaempferol (7), luteolin (8), luteolin-3`-methoxy-4`-
O-β-D-glucopyranoside (9), isorhamnetin-3-O-β-Dglucopyranoside (10) and salicin (11).