Citrus essential oils are powerful antifungal agents

In the search for safer and healthier substitutes to chemical fungicides, Algerian researchers have extracted essential oils from different species of citrus plants for testing as anti-fungal agents. They reported that the oils offered a natural means of protecting plant crops from pathogenic fungi.

The researchers received support from the Hassiba University Benbouali. They published their findings in the scientific journal Phytothérapie.

• Three hundred grams of fresh leaves from four species of citrus plants – Citrus sinensis, Citrus aurantium Amara, Citrus limon and Citrus Blanco reticulata – were collected. The hydrodistillation process extracted essential oils from the plant samples.
• Citrus limon leaves yielded the highest concentration of essential oils at 1.02 percent of weight. Second place went to Citrus sinsensis with a 0.96 percent yield.
• Researchers cultivated cultures of Alternaria alternata and a phytopathogenic species of Penicillium fungi. Various doses of the four citrus essential oils are administered to the two molds.
• Of the four species, the essential oils of Citrus aurantium, Citrus limon, and Citrus reticulata demonstrated significant anti-fungal activity. They were able to stop the radial mycelia of Alternaria alternata and Penicillium sp. from growing, thereby inhibiting the spread of the disease.
• Furthermore, the antifungal activity of the essential oil goes up when the concentration of the oil increases. The highest dosage tested was one milligram per milliliter (mg/ml).

Based on their findings, the researchers conclude that citrus essential oils could be used as natural fungicides to prevent the onset and spread of common fungal diseases that target commercially valuable plants.

The full report, which is written in French, can be browsed at this page. For more information about the fungicidal properties of citrus leaves, you can visit EssentialOils.news.

Journal Reference:

Hamdani FZ, Allem R. PROPRIÉTÉS ANTIFONGIQUES DES HUILES ESSENTIELLES DES FEUILLES DE CITRUS VIS-À-VIS D’ALTERNARIA ALTERNATA ET PENICILLIUM SP IN VITRO. Phytothérapie. 2015;15(5):263–266. DOI: 10.1007/s10298-015-0978-3.