author(s)
Nur Mohammad, Razia Akter Pone, Mominul Islam, Mahim Shefa, Konika Akter Eva, Sumaiya Nisa and Nurul Islam

abstract
The aerial part and roots
of E. tirucalli L. plant extracts collected in petroleum ether (Pet.
ether), CHCl₃ and CH₃OH were examined for antioxidant,
cytotoxic and antimicrobial activities, and only the CH₃OH extract
of the roots showed DPPH free radical scavenging activity of 20.61, 43.06,
78.13, 94.34 and 94.45% at the concentrations of 25, 50, 100, 150 and 200
μg/ml, respectively, with IC₅₀ values ​​of 2.18 μg/ml. The aerial
part showed cytotoxic effects against A. salina with LC₅₀
values ​​of 15.428, 11.286 and 5.069 μg/ml for the CHCl₃ extract
after 12, 18 and 24 h, and 373.158, 28.173, 4.275 and 1.381 μg/ml for the CH₃OH
extract after 6, 12, 18 and 24 h of exposure, respectively. The root part
showed LC₅₀ values ​​of 266.674, 181.992, 97.586 and 55.095 μg/ml
for petroleum ether; 136.676, 12.689, 10.705 and 6.167 μg/ml for CHCl₃
and 67.057, 10.717, 2.324 and 0.968 μg/ml for CH₃OH extracts, all
after 6, 12, 18 and 24 h of exposure respectively. Extracts from both parts
were subjected to antibacterial tests against three Gram-positive species (Bacillus
subtilis, Staphylococcus aureus, and Staphylococcus gallinarum) and
four Gram-negative species (Escherichia coli, Pseudomonas aeruginosa,
Serratia marcescens, and Shigella sonnei). The CHCl₃
extracts from both parts and the CH₃OH extract from the aerial part
showed activity against all bacteria tested, but the CH₃OH extract
from the roots showed activity against S. gallinarum and S.
marcescens. Quantitative estimation of the inhibition zones of the extracts
showed various ranges of antibacterial activity against the bacteria tested.