الفهرس 
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Abstract
Chemical and Biological Investigation of Gmelina
arborea and Tectona grandis (Family Verbenaceae)’’.
In the present study, the 90% methanolic extract of the
leaves of Tectona grandis Linn. (Verbenaceae) and
Gmelina arborea Roxb. (Verbenaceae), as well as their
derived sub-fractions (petroleum ether, chloroform, ethyl
acetate and n-butanol); were evaluated as antioxidants
using three different quantitative assays; 1,1’-diphenyl-2-
picrylhydrazyl free radical scavenging,
phosphomolybdenum and reducing power assays as well as
qualitative one (dot-blot and DPPH staining assay). Also,
their cytotoxic activity was carried out via brine shrimp
lethality (BSLT) test and toward human liver-carcinoma
cell line (HepG-2), using Sulphorhodamine-B assay. The
results revealed that the 90% methanolic extract of the two
plants and their derived ethyl acetate and butanol
subfractions exhibited high antioxidant and cytotoxic
activities. Also, the antioxidant activity of the tested
extracts of the two plants was found to be in highly positive
correlation with their total phenolic contents (TPC).The results showed that the DPPH activity of T.grandis,
ranged from (10.63 to 19.58 μg/ml); TAC ranged from
(589.50 to 400.30; mg AAE /g extract); RPAA (OD value)
ranged from (0.783 to 0.423; 200 mg/ml) and TPC ranged
from (400.56 to 208.32; mg GAE/g extract). A positive
linear relationship existed between antioxidant activity and
TPC (all R2 values > 0.91). The results showed that the
mortality of brine shrimp larvae (LC50) against different
dosage of defatted 90% methanol, n-BuOH and EtOAc was
(100, 15.84 and 125.89) respectively. Also, the HepG-2
results showed that defatted 90% MeOH and n-BuOH
fractions have cytotoxic activity with IC50 ≤ 20 μg/ml
which falls within the American Cancer Institute (ACI)
criteria.
Also, the results showed that the DPPH activity of
G.arborea ranged from (14.10 to 28.94 μg/ml); total
antioxidant capacity (518.45 to 390.41; mg AAE/g extract);
reducing power (0.715 to 0.396; 200 mg/ml) and total
phenolic (400.66 to 244.76; mg GAE/g extract). A positive
linear relationship existed between antioxidant activity and
TPC (all R2 values > 0.92). The results showed that the
mortality of brine shrimp larvae (LC50) against different
dosages of defatted 90% methanol, n-BuOH and EtOAc
respectively was (158.48, 39.81 and 199.52; μg/ml). Also,
the results of HepG-2 assay showed that n-BuOH fraction
have cytotoxic activity with IC50 ≤ 20 μg/ml (IC50= 17.3
μg/ml) which falls within the American Cancer Institute
criteria followed by the defatted 90% methanol and EtOAc
(IC50= 22.1 μg/ml) fractions.
Owing to high antioxidant of the 90% methanolic extract
of the two plants under investigation and their derived ethyl
acetate and butanol fractions, these promising fractions will
be subjected to chromatographic isolation.
The chemical constituents of the 90% methanolic extract
of the two plants and their derived ethyl acetate and butanol
subfractions were detected and identified via different
chromatographic techniques and structural elucidation of
the isolated pure compounds was performed via different
spectroscopic techniques such as UV, IR and NMR (1HNMR,
13C-NMR) beside certain chemical methods.
Two compounds were isolated from the ethyl acetate
fraction of the 90% methanol extract of T.grandis and eight
compounds were isolated from n-butanol fraction using
different chromatographic techniques. On the basis of
certain spectroscopic analysis, their chemical structures
were elucidated as; quercetin (B.T1), apigenin (B.T2), gallic
acid (B.T3), quercetin-3-O-1C4-α-L-rhamnoside (quercetrin)
(B.T4), 5’-O-caffeoyl quinic acid (Chlorogenic acid) (B.T5),
diosmin (diosmetin-7-O-rutinoside) (B.T6), kaempferol- 3 -
O - α - 1C4 - L - rhamnopyranosyl - (1’’’→6’’) - O - β - D -
4C1 - glucopyranoside (B.T7), 3’ - methoxy - taxifolin - 7 -O
- α - L - 1C4 – rhamnopyranosyl - (1’’’→6’’) - O - β - D -4C1 -
galactopyranoside (B.T8), taxifolin (dihydroquercetine)
(E.T1) and hesperidin (3’,5,7 - trihydroxy - 4’ - methoxyflavanone
- 7 - O - rhamnoglycoside) (E.T2).
from the ethyl acetate fraction of the 90% methanol
extract of G.arborea, two compounds have been isolated
whereas six compounds were isolated from n-butanol
fraction of the 90% methanol extract of the plant using
different chromatographic techniques. Their chemical
structures were determined as; 5, 7, 3’, 4’ - tetrahydroxy -
flavone (luteolin) (B.G1), luteolin-4’-O-β-D-4C1-galactoside
(B.G2), 3, 5, 7, 4’ - tetrahydroxy - flavone (kaempferol)
(B.G3), quercetin - 3 - O - β - D - 4C1 -glucopyranoside
(isoquercitrin) (B.G4), quercetin - 3 - O - α - 1C4 - L -
rhamnopyranosyl - (1’’’→6’’) - O - β-D-4C1-glucopyranoside
(rutin) (B.G5), luteolin-7-O- β-D-4C1-galactoside (E.G1) and
ENGLISH SUMMARY
XXIII
quercetin-3-O-α-1C4-L- rhamnopyranosyl-(1′′′→6′′)-β-4C1-
D-galactopyranoside (quercetin-3-O-robinobioside) (E.G2).
The biological activity of the isolated compounds from
T.grandis revealed that; the DPPH free radical antioxidant
activity ranged from (3.85 μg/ml) to (14.75 μg/ml), while
the total antioxidant capacity was ranged from (710.23 mg
AAE /g compound) to (386.45 mg AAE /g compound). The
cytotoxic activity against human liver-carcinoma cell line
(HepG-2) showed that all the tested compounds have
cytotoxic activity with IC50 ranged from 3.53 to 15.40
μg/ml.
The biological activity of the isolated compounds from
G.arborea revealed that; the DPPH free radical antioxidant
activity ranged from (5.70 μg/ml) to (14.40 μg/ml), while
the total antioxidant capacity ranged from (630.75 mg
AAE/g compound) to (403.66 mg AAE/g compound). The
cytotoxic activity using HepG-2 assay showed that all the
tested compounds have cytotoxic activity with IC50 ranged
from 3.38 to 15.70 μg/ml.