Evaluation of antifungal activity of seaweed extracts

Abstract

Seaweeds are subject to numerous biological interactions and sometimes to extreme abiotic conditions, so they have developed among other defense mechanisms, the ability to produce biologically active substances. Thus, these organisms produce mainly terpenes and phenols. Among others, the antifungal activity, due to its importance in human and animal health and the production of agricultural products, has been the subject of several studies. In the present work, this activity was investigated in ten seaweeds extracts, by direct bioautography assays, compared to Colletotrichum lagenarium and disk diffusion assay, compared to Aspergillus flavus. The organisms studied were: Stypopodium zonale, Laurencia dendroidea, Ascophyllum nodosum, Sargassum muticum, Pelvetia canaliculata, Fucus spiralis, Sargassum filipendula, Sargassum stenophyllum, Laminaria hyperborea and Gracilaria edulis. S. zonale, L. dendroidea, P. canaliculata, S. muticum, A. nodosum and F. spiralis extracts significantly inhibited the C. lagenarium growth, but not inhibited significantly the A. flavus growth. The presence of terpenes in all of these extracts was confirmed by thin layer chromatography whereas the presence of phenolic compounds was confirmed only in extracts of P. canaliculata, A. nodosum and S. muticum. In chemical study by column chromatography, followed by gas chromatography/mass spectrometry analysis, the terpenes neophytadiene, cartilagineol, obtusol elatol; and the ester ethyl hexadecanoate were identified in the L. dendroidea extract. This is the first report on the activity of seaweed extracts against C. lagenarium, a fungus bearing agricultural importance.Index terms: Etanolic extract, Colletotrichum lagenarium, Aspergillus flavus. RESUMOAs macroalgas marinhas, por estarem sujeitas a numerosas interações biológicas e, por vezes, a condições abióticas extremas, desenvolveram, entre outros mecanismos de defesa, a capacidade de produzir substâncias biologicamente ativas. Assim, esses organismos produzem, principalmente, terpenos e fenóis. Entre outras, a atividade antifúngica, por sua importância na saúde humana e animal e na preservação de produtos agrícolas, tem sido objeto de diversos estudos. No presente trabalho, esta atividade foi investigada em dez extratos de macroalgas marinhas, por ensaios de bioautografia direta, frente ao fungo Colletotrichum lagenarium e por ensaio de difusão em disco, frente ao Aspergillus flavus.

Enhancement of Calibrachoa growth, secondary metabolites and bioactivity using seaweed extracts

“…For example, some SWEs have bactericidal effects [18] associated with the presence of terpenes and phenolic compounds [17, 19]. Other reports indicate that seaweeds might stimulate the production of plant defense elicitors (e.g.…”

Control of Fusarium Dry Rot Incited by Fusarium oxysporum f. sp. tuberosi Using Sargassum vulgare Aqueous and Organic Extracts

“…Production of terpenes and phenols by some seaweed species has the potential to inhibit the growth of various fungal plant pathogens [50]. These bioactive polyphenol compounds, acting singly or in combination, interfere with the life process of fungi by binding their protein molecules, acting as chelating agents, altering structural component synthesis, weakening or destroying the permeability barrier of the cell membrane and changing the physiological status of cells.…”

Antifungal Potential in Crude Extracts of Five Selected Brown Seaweeds Collected from the Western Libya Coast

“…Aspergillus niger showed resistance against majority of methanolic extracts. In Brazil, Peres, et al (2013) reported that ten seaweed extracts significantly inhibited the Colletotrichum lagenarium growth, but not inhibited significantly the Aspergillus flavus growth [13]. In Ireland, Rajauria and Abu-Ghannam (2013) screened antimicrobial activity and bioactive compounds of Himanthalia elongate (Brown Seaweed) [14].…”