Differential effects of methanolic extracts of clove, ginger, garlic and eucalyptus essential oils on anti-parasitic partitivities of G. lamblia and E. histolytica : an in vitro study

Plants and essential oils are used in traditional medicine against parasitic intestinal protozoal diseases. The current study revealed the GC–MS analysis and anti-parasitic effects of four medicinal plant species from the Saudi Arabia. All essential oils showed significant variations in chemical constituents. 15 different chemical constituents were present in Eucalyptus camaldulensis, Syzygium aromaticum, Zingiber officinale, except Allium sativum that showed the presence of diverse 21 chemical compounds. Significant anti-parasitic inhibition was observed against G. lamblia and E. histolytica when treated with E. camaldulensis (100%, 100%) , S. aromaticum (74.81%, 86.4%) , Z. officinale (77.62%, 100%) and A. sativum (98.79%, 74.84%) at a dose rate of 100 µg/mL to control G. lamblia and E. histolytica parasites, respectively. Low to high levels of inhibition percentages were noticed when concentration of essential oils was increased from 25 to 100 µg/mL. The extracts of essential oils from all plants revealed the presence of mono-terpenes, alkenes, aldehydes, hexanes, sesquiterpenes, alkanes, propenes, phenyls, esters, alcohols, and hydrocarbons. All extracted natural extracts showed cytotoxicity test values over 50% which were considered cytotoxic during their interaction with parasitic cells. Results of current experiment can be lead further for future in vivo trials.