Isolation and Purification of Antifungal Compounds from the Green Microalga Chlorella vulgaris

Document Type : Original Article

Authors

Food Toxicology and Contaminants Department, National Research Centre, Cairo, Egypt

Abstract

Introduction: The current study aimed to purify antifungal compounds from Chlorella vulgaris extracts, fractions, sub-fractions and pure compounds against different strains of mycotoxigenic fungi.
Materials and Methods: Antifungal activity was conducted using disc diffusion assay, TLC-bioautography and Minimum Inhibitory Concentration (MIC). Isolation, purification and structure elucidation of antifungal compounds were carried out using column chromatography, Thin Layer Chromatography (TLC), UV-Vis spectrophotometer, Gas Chromatography–Mass Spectrometry (GC-MS), and Nuclear Magnetic Resonance (NMR).
Results: C. vulgaris Diethyl Ether Extract (DEE) showed the highest antifungal activity against all tested fungi with inhibition zone from 11.5 to 21.9 mm. By fractionation of DEE, Fraction F3 (chloroform:methanol, 50:50) and F5 (methanol 100%); sub-fraction CF3-10 and CF5-10 exhibited antifungal activity against all tested fungi. Two pure compounds, hydroxyphenophytin B and hexadecanoic acid methyl ester, with antifungal activity were isolated from CF3-10 and CF5-10, respectively.
Conclusions: C. vulgaris DEE and isolated compounds can be used as promising antifungal agents from natural sources against mycotoxigenic fungi at post-harvest or storage stages. 

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