Clove oil
Numerous studies (such as this one) show the fungicidal effect of clove oil, thanks to its main compound called eugenol. This compound damages the cell membrane of a fungus, causing its cell contents to leak out and ultimately destroying the fungus itself.
One study examined various herb oils against the mold genera Aspergillus and Penicillium, which are both ubiquitous in indoor spaces. It found that “cloves, cinnamon, and mustard seem to be the most effective of those tested,” completely inhibiting mycotoxin production even when the amount of spice in the solution was less than one percent.
And get this: a separate review concluded that the fungicidal effect of clove EO is comparable to that of commercial disinfectants! This is the scientific research that convinced me to incorporate clove oil in my homemade mold solution (which I’ll share with you further below).
Cinnamon oil
When you get a whiff of that well-loved cinnamon aroma, it means mold-fighting is happening! Cinnamon’s taste and smell come from a natural compound called cinnamaldehyde, which happens to be antifungal. Research found that even cinnamaldehyde vapours are “strong antimicrobials against airborne microbes.”
On top of that, cinnamon oil is also packed with the fungicidal compound eugenol – the same ingredient that makes clove oil so powerful against mold.
Mustard oil
Allyl isothiocyanate – AITC for short – is the compound that gives mustard seeds their pungent flavour plus fungus-fighting power. Scientists believe that AITC (and other ITCs) creates a chemical reaction that destroys fungi proteins. This substance is so effective that some organic farms in Asia use it as a fumigant to protect their plants from fungi.
Want more proof? One study saw that black mustard oil, when deployed as vapour, impeded the growth of Aspergillus and Penicillium on bread and prevented these molds from recovering!
Thyme oil
Thyme oil contains the aptly-named substance thymol, known to stop mold. It works similarly as eugenol by breaking down the cell membranes of fungi and causing them to die out.
A group of Croatian scientists investigated how this would work on mold growing on walls. Not just Aspergillus and Penicillium, mind you, but also a handful of other common types such as Cladosporium and Trichoderma. They found that thyme oil vapours “strongly suppressed” mold growth after 60 days, and that this suppressive activity could be long-lasting.
Oregano oil
Oregano essential oil also has thymol, plus its own mold-killing compound called carvacrol. Just like eugenol and thymol, carvacrol disrupts the cell walls of fungi, causing cell death. In one lab test, oregano EO inhibited the growth of three species of Aspergillus mold: A. niger, A. flaous, and A. ochraceus. As a bonus, the oil also helped impede Staph and Salmonella bacteria!
Orange oil
We all know oranges as immune-boosting foods through the vitamin C they provide, but they can also protect us through their essential oils! Orange essential oil is rich in limonene, a volatile organic compound that disrupts the growth of mold. Dozens of studies have found the antimicrobial actions of limonene against all sorts of fungi, from Aspergillus to Penicillium to Trichophyton.
In one journal article I particularly like, scientists created a type of paper meant to be applied on fungal-infected skin. The paper, made with orange oil, “exhibited complete inhibition of growth” of the Aspergillus, Penicillium, and Rhizopus molds they tested. Such a potent result from something so sweet-smelling!
HJ Tagupa
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