Antifungal Activity of Lower Alkyl Fatty Acid Esters against Powdery Mildews

Abstract

In the course of a searching environmental friendly antifungal compounds, we found that mixture of methyl esters of fatty acids obtained from soybean oil had potent control efficacy against barley powdery mildew (Blumeria graminis f. sp. hordei). In this study, ten alkyl fatty acid esters (AFAEs) were tested for in vivo antifungal activity against five plant diseases such as rice blast, rice sheath blight, tomato gray mold, tomato late blight and barley powdery mildew. Some AFAEs showed the most control efficacy against barley powdery mildew among the tested plant diseases. By 5-hr protective and 1-day curative applications, six AFAEs (3,000 µg/ml), including methyl and ethyl palmitates, methyl and ethyl oleates, methyl linoleate, and methyl linolenate demonstrated both curative and protective activities against barley powdery mildew. In contrary, methyl laurate strongly controlled the development of powdery mildew on barley plants by curative treatment at a concentration of 333 µg/ml, but did not show protective activity even at 3,000 µg/ml. Under greenhouse conditions, the seven AFAEs (1,000 µg/ml) except for methyl and ethyl stearates, and methyl caprylate also effectively controlled cucumber powdery mildew caused by Podosphaera xanthii. Among them, methyl and ethyl palmitates (333 µg/ml) represented the most control activity of more than 68% against the disease. The results are the first report on the antifungal activity of methyl and ethyl esters of fatty acids against plant pathogenic fungi.

Evaluation of antifungal activity of free fatty acids methyl esters fraction isolated from Algerian Linum usitatissimum L. seeds against toxigenic Aspergillus

“…We believe also that antifungal effect may be due to the abundance of linoleic and linolenic acids in linseed oil [44] . This assumption has been confirmed by Choi et al [12] .…”

“…A wide spectrum of biological substances extracted from medicinal plants, including oils were tested to replace some of the ways to fight against xenobiotics including fungi. In this section several authors have confirmed the effectiveness of the oils on toxigenic fungi [10][11][12] .…”

“…Extraction was carried out with Petroleum ether for 6 h without interruption by heating around 40 to 60°C. After the extraction, solvent was evaporated on the Buchi-Rotavapor until no odour of solvent remains and finally oil (6.8 g) was collected in a separate beaker for further analysis [12] .…”

Antifungal Activity of Skin Secretion of Bleeding Toad <i>Leptophryne Cruentata</i> and Javan Tree Frog <i>Rhacophorus Margaritifer</i>

“…Fatty acids and their derivatives have been reported to possess antifungal activity (Pohl et al, 2011;Choi et al, 2010). The most important target of antifungal fatty acids is the cell membrane.…”

Phytochemical Screening and Antifungal Activity of Saponin Extract From Algerian Silene Hoggariensis Quezel

“…Mycelial radial growth was measured from the third day of incubation 18,19 . The inhibition percentage of mycelial growth was calculated using the following formula: (PIg= ((DT-D)/DT)*100 where DT is mean diameter of mycelial growth in control and D is mean diameter of mycelial growth in treatment 20 . From the dishes used for the evaluation of the radial growth on solid medium for each fungal strain tested (dishes incubated at 25°C for 10 days) were taken four washers 5mm diameter and transposed into tubes containing 9ml of physiological salt solution and 5% Tween 80 (few drops of).…”