Chemical Characterization and Anti-Oomycete Activity of Laureliopsis philippianna Essential Oils against Saprolegnia parasitica and S. australis

Abstract

Laureliopsis philippiana (Looser) R. Schodde (Monimiaceae) is a native tree widespread in the forest areas in the south of Chile and Argentina, known for its medicinal properties and excellent wood. The aim of this study was to evaluate the chemical composition of L. philippiana leaf and bark essential oils (EOs) using gas chromatography-mass spectrometry (GC-MS), and to quantify its anti-oomycete activity, specifically against OPEN ACCESSMolecules 2015, 20 8034Saprolegnia parasitica and S. australis. Only six components were identified in leaf EO, 96.92% of which are phenylpropanoids and 3.08% are terpenes. As for bark EO, 29 components were identified, representing 67.61% for phenylpropanoids and 32.39% for terpenes. Leaf EO was characterized mainly by safrole (96.92%) and β-phellandrene (1.80%). Bark EO was characterized mainly by isosafrole (30.07%), safrole (24.41%), eucalyptol (13.89%), methyleugenol (7.12%), and eugenol (6.01%). Bark EO has the most promising anti-Saprolegnia activity, with a minimum inhibition concentration (MIC) value of 30.0 µg/mL against mycelia growth and a minimum fungicidal concentration (MFC) value of 50.0 μg/mL against spores; for leaf EO, the MIC and MFC values are 100 and 125 µg/mL, respectively. These findings demonstrate that bark EO has potential to be developed as a remedy for the control of Saprolegnia spp. in aquaculture.

Saprolegnia parasitica Isolated from Rainbow Trout in Korea: Characterization, Anti-Saprolegnia Activity and Host Pathogen Interaction in Zebrafish Disease Model

“…Saprolegniasis (also known as saprolegniosis) is considered as one of the most common and devastating oomycete diseases in hatcheries and farms of salmon and trout [ 1 ]. Saprolegnia species affect to decline of the wild fish [ 2 ] and cause diseases in amphibians and crustaceans [ 3 ]. The species belonging to the genus Saprolegnia (class Oomycetes) are considered to be the causative agents of the saprolegniasis, and often considered as opportunistic facultative parasites [ 4 ].…”

Hemi-Synthesis and Anti-Oomycete Activity of Analogues of Isocordoin

“…The method used in this study for anti-oomycete activity assay was performed according to methods previously reported [ 34 ]. The compounds 1 – 8 were tested at 200.0, 150.0, 100.0, 50.0, 25.0, 12.5, 6.3, and 3.1 µg/L to find a preliminary minimum inhibitory concentration (MIC) interval.…”

“…The spore germination assay against Saprolegnia strains was performed according to the agar dilution method [ 35 ]. The minimum oomyceticidal concentration (MOC) and detailed protocols for the biological assays was defined previously [ 34 ].…”

“…Inhibition of mycelial growth was assayed using the method described by Hu [ 29 ] with small modifications. Oomycete growth was measured as the colony diameter, and toxicity of the compounds 1 – 8 against Saprolegnia strains was measured in terms of the percentage of mycelia inhibition by a formula described in detail elsewhere [ 34 ].…”

Biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum) using two bacterial isolates (LE89 and LE141) of Pseudomonas fluorescens

“…In addition, none of the available compounds offers sufficient protection after the rearing period (Forneris et al, ). Among the alternatives to chemotherapy are the use of plant extracts (Chukanhom, Borisuthpeth, & Hatai, ; Hashemi Karouei, Sadeghpour Haji, & Gholampour Azizi, ; Khosravi, Shokri, Sharifrohani, Mousavi, & Moosavi, ; Madrid et al, ; Udomkusonsri, Trongvanichnam, Limpoka, & Klangkaen, ) or probiotics (Lategan, Torpy, & Gibson, ; ).…”