2. Materials and methods
2.1. Plant material
Authenticated medicinal plants were collected
from the Eastern Ghats of Southern India
during November 2002. The botanical
identification was made by Dr. K. Hemadri
and voucher specimens were deposited at the
herbarium of Laila Impex Research Centre,
India.
2.2. Preparation of extracts
The plant materials were dried under shade
and grinded to a coarse powder. Powdered
plant materials (each 25 g) were individually
extracted with water / hydro-alcohol / alcohol
(200 ml) and then filtered. Filtrates were
concentrated dried under vacuum and subjected
for activity studies.
2.3. Cytotoxicity bioassay
Brine shrimp lethality bioassay was carried
out to investigate the cytotoxicity of extracts
of medicinal plants of India. Brine shrimps
(Artemia salina) were hatched using brine
shrimp eggs in a conical shaped vessel (1L),
filled with sterile artificial seawater (prepared
using sea salt 38 g/L and adjusted to pH 8.5
using 1N NaOH) under constant aeration for
48 h. After hatching, active nauplii free from
egg shells were collected from brighter portion
of the hatching chamber and used for the
assay. Ten nauplii were drawn through a glass
capillary and placed in each vial containing
4.5 ml of brine solution. In each experiment,
0.5 ml. of the plant extract was added to 4.5
ml of brine solution and maintained at room
temperature for 24 h under the light and surviving
larvae were counted. Experiments
were conducted along with control (vehicle
treated), different concentrations (1-5000g/ml) of the test substances in a set of three
tubes per dose