Antibacterial activity of Quassia indica (Gaertn.) nooteboom extracts / Intan Zawanah Eshaap

Developing countries in the world rely on medicines that use plant extract products. Nevertheless, the antibacterial activity of most plant extracts has not been completely explored. Ethanol and methanol extracts of Quassia indica were studied for their antibacterial activity against one Gram-positive and one Gram-negative bacteria using disc diffusion method. The aims of this study were to extract a crude sample of Quassia indica with different solvents and to determine the antibacterial activity of Quassia indica towards Gram-Positive bacteria (Staphylococcus Aureus) and Gram-Negative bacteria (Escheria Coli). The plant was extracted using rotary evaporator unit to obtain crude extract of the plant. Methanolic extract was observed to give higher inhibition zones compared to ethanolic extract. Higher inhibition zones were produced when ethanolic and methanolic plant extracts tested against E. coli compared to S. aureus. However, both bacteria were resistant to plant extracts. For positive controls, E. coli is more resistant while S. aureus is more sensitive against antibiotics. Smaller inhibition zones were produced when plant extracts acted against bacteria compared to antibiotics. Thus, the presence of clear zone showed that the Quassia indica possess antibacterial activity against tested bacteria.