Antibacterial, Antiviral and Antifungal Activity of Essential Oils: Mechanisms and Applications

Abstract

Essential oils are natural products which combine antimicrobial and antioxidant activity, thus providing natural protection against microbial pathogens and other undesirable agents. Among the essential oils extracted from aromatic plants, oregano (Origanum vulgare) and thyme (Thymus vulgaris) oils have been proposed for different biomedical and industrial applications. The antimicrobial mechanisms found in these essential oils have been explained on the basis of their content in natural compounds such as carvacrol, thymol, p-cymene and c-terpinene, among others. Although these two essential oils have received much attention, scientists working in the fields of biomedicine and food science, among others, are paying increasing attention to a wider variety of aromatic natural oils in an effort to identify novel and natural applications for the inhibition of microbial pathogens. Accordingly, a detailed revision of the main essential oils and their applications in biomedicine, food science and other industrial fields is presented. The review not only focuses on the main antibacterial applications reported to date, but also in the current and future developments for the inhibition of virus and fungi.

Antimicrobial Properties of Plant Essential Oils against Human Pathogens and Their Mode of Action: An Updated Review

“…The major component (~90%) of bioactive essential oils is constituted of monoterpenes [103]. Some of the major compounds include monoterpene hydrocarbons ( p -cymene, limonene, α -pinene, and α -terpinene), oxygenated monoterpenes (camphor, carvacrol, eugenol, and thymol), diterpenes (cembrene C, kaurene, and camphorene), sesquiterpene hydrocarbons ( β -caryophyllene, germacrene D, and humulene), oxygenated sesquiterpenes (spathulenol, caryophyllene oxide), monoterpene alcohols (geraniol, linalool, and nerol), sesquiterpene alcohol (patchoulol), aldehydes (citral, cuminal), acids (geranic acid, benzoic acid), ketones (acetophenone, benzophenone), lactones (bergapten), phenols (eugenol, thymol, carvacrol, and catechol), esters (bornyl acetate, ethyl acetate), and coumarins (fumarin, benzofuran) [1, 4, 8, 13, 104, 105]. The structures of some of these compounds are represented in Figure 1.…”

“…So far, only a limited number of drugs are effective against many of these viruses, which has prompted research into finding new antiviral lead molecules. From our literature survey, it is evident that many essential oils possess antiviral properties against many DNA and RNA viruses, such as herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), dengue virus type 2, Junin virus, influenza virus adenovirus type 3, poliovirus, and coxsackievirus B1 [96, 105, 114, 133, 134]. …”

“…At present, various essential oils may be a promising alternative against viral infections [105]. However, the detailed understanding on the antiviral action of essential oils still requires more research.…”

Chemical profile and antifungal potential of essential oils from leaves and flowers of Salvia algeriensis (Desf.): A comparative study

“…Considering the difference observed between part of S. algeriensis, the superiority of leaves oil might to be due to the fact of presence of some known antifungal constituents in its chemical profile such as carvacrol (Soylu et al, 2006), eugenol and linalool (Böhme et al, 2014). However, the possible synergistic and modulatory functions of other constituents should not been neglected (Davicino et al, 2007).…”

Radical Scavenging and Disinfectant Effect of Essential Oil From Moroccan Mentha Pulegium

“…According to this finding, the whole essential oil exhibits an interesting radical scavenging effect even if the BHT was more active. However, the synthetic antioxidants have fallen out of favor because they are suspected of being carcinogenic and allergic [27].…”