In vitro Antioxidant Analysis and the DNA Damage Protective Activity of Leaf Extract of the Excoecaria agallocha Linn Mangrove Plant - Agricultural Chemistry - page 159

Miniprep Kit (Sigma - Aldrich USA). A mixture of 10 l of hexane, water and methanol
extract (100 g/l), and plasmid DNA (0.5g) was incubated for 10 min at room temperature
followed by the addition of 10 l of Fenton's reagent (30 mM H 2 O 2 , 50 M ascorbic acid and
80 M of FeCl 3 ). The final volume of the mixture was made up to 20 l with double distilled
water and incubated for 30 min at 37 o C. The DNA was analysed on 1 % agarose gel using
ethidium bromide staining and photographed in Gel Doc. Quercetin (50 M) was used as a
positive control [12].

4.8. Phytochemical analysis

Chemical tests were carried out on the aqueous extract of the powdered specimens using
standard procedures to identify the constituents as described by Harborne [13].

5. Results and discussion

5.1. Antimicrobial activity

This paper illustrates the antimicrobial, antioxidant and DNA protective effect of Excoecaria
agallocha Linn leaf extract. The phytochemical constituent of E. agallocha Linn can be
summarized as follows: methanolic leaf extract shows the presence of saponin, tannin and
a high content of terpinoids, whereas cardiac glycosides are absent. The antimicrobial
activities of methanol extract of Excoecaria agallocha Linn leaf is summarized in Table 1.
The extract of E. agallocha reported to have significant in vitro antibacterial activity
against Staphylococcus aureus, Shigella dysenteriae, Shigella sonnei and Enterococci with the
zones of inhibition ranging from 11 to 15 mm, and no significant activity was reported
against Shigella flexneri and Staphylococcus epidermis at test concentrations [14].

Microbes
Sample

+ve 1 2 3 4

B.subtilis 17 NI NI NI NI

S.pyogenes NI NI NI NI NI

E.coli 13 12 NI NI 10

S.typhi 15 12 NI NI 11

K.pneumoniae >10 12 NI NI 10

S.marcescens 36 11 10 NI 10

V. Cholerae (01) 10 11 10 NI 10

V. Cholerae (08) 15 10 NI NI 10

Ampicillin used as positive control and the solvent used as negative control, activity expressed in millimole - mm
concentration. (NI- no inhibition).
Table 1. Antimicrobial activity of different fractions (500mg/6mm disc) of Excoecaria a gallocha Linn.