Plants have proven their medicinal properties time and again. Studies have shown that the most potent antibacterial substances available come in the form of plant essential oils. Researchers from India evaluated the essential oil of Inula cappa (sheep's ear) for its antibacterial properties. The study, which appeared in the Journal of Essential Oil Research, is the first report of the bioactivity and essential oil composition of I. cappa.
Inula is a large genus of about 90 species of flowering plants in the family Asteraceae, native to Europe, Asia and Africa. They may be annuals, herbaceous perennials or subshrubs. They vary greatly in size, from small species a few centimeters tall to enormous perennials over 3 m (10 ft) tall. I. cappa grows wild in the central Himalayan region (India). It is a shrub growing to 1.8 m (6 ft).
The researchers analyzed I. cappa essential oil using capillary GC and GC-MS. The sesquiterpene hydrocarbons constituted almost 50 percent of the oil.
They identified 54 constituents which represented 90.2 percent of the oil. The principal constituents were beta-Caryophyllene (27.5 percent), cis-dihydro-mayurone (6.7 percent), beta-bisabolene (6.5 percent) and (E)-beta-farnesene (5.6 percent).
The researchers tested the antibacterial activity of I. cappa essential oil against 10 bacterial strains and found significant activity against Enterococcus faecalis, Klebsiella pneumoniae, Xanthomonas phaseoli, and Bacillus subtilis.
There is evidence to suggest that I. cappa essential oil possess antibacterial properties that work against certain bacterial strains commonly found in the human gut.
Potent antibacterial essential oils
The following essential oils have all been shown to have antibacterial properties. Combat bacterial illness the natural way with these essential oils.
Peppermint essential oil -- This potent substance has been proven to be a well-rounded antibacterial essential oil. A study published in the U.S. National Library of Medicine shows that peppermint essential oil is effective against all 22 types of bacteria used in the study.
Eucalyptus essential oil -- The above-mentioned study also tested eucalyptus essential oil and found that it too is effective against all 22 strains of bacteria used in the test.
Tea tree oil -- In a study that appeared on the National Center for Complementary and Integrative Health, tea tree oil was found to be bactericidal against antibiotic-resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). Tea tree oil may provide natural wound-healing therapy for people who suffer from MRSA-type bacterial infections.
Citronella oil -- This oil is often used as a natural insect repellent, but it has also proven to work against systemic bacteria such as those found in the digestive tract, which cause infections in the colon, stomach, intestines and kidneys.
Thyme essential oil -- A study published in the Thieme E-Journals shows that thyme essential oil is effective against recurrent episodes of bacterial vaginosis, making it an ideal natural alternative to antibiotics.
Cinnamon essential oil -- One study, which appeared in the Journal of Diseases and Medicinal Plants, showed that cinnamon essential oil had the strongest bactericidal activity against pathogens and germs found in food compared to thyme and clove oils. Other studies show that cinnamon essential oil is also effective against human infectious pathogens such as staph and E. coli.