Compact oregano or Origanum compactum is an aromatic plant belonging to the Lamiaceae family. It is originally from North Africa and more particularly from the Maghreb area. It is widely cultivated and used in Morocco. Compact Oregano essential oil is obtained from the flowering tops.
Compact Oregano essential oil is traditionally used for its anti-infectious properties at the respiratory, urinary or intestinal level and for infectious and parasitic dermatoses such as scabies, mycosis, ringworm and abscess. It is also invigorating and stimulating. Its main components are carvacrol and thymol.
Origanum compactum essential oil shows anti bacterial activity against S. pyogenes, P. aeruginosa, S. thyphimurium, S. enteritidis, K. pneumoniae, B. bronchiseptica, E. faecalis, L. monocytogenes, S. epidermidis. It inhibits the growth of avian strains of E. Coli resistant to colistin and enrofloxacin (MAYAUD & al., 2008 ; BOUHDID & al., 2009 ; BOUYAHYA & al., 2020).
It was shown to be more effective in inhibiting the growth of E.Coli and B. subtilis than streptomycin and chloramphenicol. It induces larger areas of inhibition than the two antibiotics, used as positive controls. In this study, the essential oil obtained from flowers showed better efficacy than that obtained from the post-flowering plant (BOUYAHYA & al., 2019).
This anti-bacterial effect is associated with an increase in the membrane permeability of bacteria, caused by carvacrol, leading to a decrease in its integrity. This membrane weakening induces in particular the leakage of potassium ions, DNA damage and disruption of ATP and protein production. In addition, thymol and carvacrol reduce the formation of biofilms by bacteria (BOUHDID & al., 2009 ; BOUYAHYA & al., 2019 ; BOUYAHYA & al., 2020).
In S. aureus compact oregano essential oil decreases the expression of genes responsible for the production of enterotoxins A, C and E (BOUYAHYA & al., 2020).
Studies on Penicillium digitatum have shown that extract of compact oregano inhibits the growth of this fungus up to 83% (BOUYAHYA & al., 2020).
Origanum compactum essential oil also inhibits the growth of Botrytis cinerea in vitro at a very low concentration (BOUCHRA & al., 2003).
Origanum compactum essential oil has a dose-dependent lethal effect on larvae, eggs and adults of Tetranychus urticae, a mite pest in crops. At a concentration of 4%, it causes 100% mortality at all stages of development (BOUYAHYA & al., 2020). It is also effective against Spodoptera littorali, a butterfly whose caterpillars ravage certain types of plantations (BOUYAHYA & al., 2020).
Oregano essential oil showed a good antioxidant effect in the DPPH test, thanks to its high content of carvacrol and thymol. Its effectiveness is comparable to that of vitamin C (EL BABILI & al., 2011 ; BOUYAHYA & al., 2020).
