Cytotoxic Activity
Bioassay: Anti cancer activity of endophytic fungi secondary metabolite was measured
based on its cytotoxic effect. The cell lines HepG2 cells, MCF7 cells, A549 cells, A431 and HeLa
cells obtained from the National Centre for Cell Science (NCCS), University of Pune Campus,
Pune were used for the study. The tumour cells were maintained in the Minimum essential medium
(Eagle’s) supplemented with 2Mm L-glutamine and Earle’s BSS adjusted to contain 1.5g/L
Sodiumbicarbonate, 10% fetal calf serum and 100μg/mL streptomycin (Sigma). The cells were
incubated at 37°C in an atmosphere of 5% CO2 and 95% air with more than 95% humidity. 1000
µl of each cell suspension were added into each of the 24 multi-well plate followed by the addition
of 10μL ethyl acetate extract of endophytic fungi metabolite and methanolic plant extract at three
different concentrations 2.5, 5 and 10μg mL-1 and incubated for 48 h. As a negative control, cells
were treated with only Eagle’s MEM with 10μL ethyl extract for endophytic fungi and methanol
for plant sample. Each treatment was done in triplicates. The viable cells were counted in a
haemocytometer using the trypan blue exclusion method (Kumala et al. 2006). Cytotoxic assay
other than the MTT assay were used in this study, because direct cell counting by haemocytometer
is one of the simplest method, inexpensive, accurate measure of cell number to assess the cytotoxic
effect of secondary metabolites of endophytic fungi.
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To calculate IC50 values of secondary metabolites in ethyl acetate extract from endophytic fungi
Penicillium sp. isolate, following formula was used:
Total number of viable cells per ml o