Abstract

Many studies have demonstrated the effectiveness of algicidal compounds produced by macrophytes against microalgae. The aim of this study was to assess the algicidal activity of seven Moroccan macrophyte ethyl acetate extracts (MEA) to control harmful algal blooms (HABs). The response and sensitivity of prokaryotic toxic cyanobacteria (Microcystis aeruginosa) and eukaryotic microalgae (Chlorella sp.) were highlighted. The algicidal effect of MEA extracts against the two microalgae was assessed using both the paper disc diffusion and microdilution methods. This last was used in order to evaluate the minimum inhibitory concentrations (MIC) and minimum algicidal concentrations (MAC). Results showed that the growth of both microalgae was significantly inhibited by all MEA extracts. Myriophyllum spicatum organic extract shows the highest growth inhibition activity against M. aeruginosa (35.33 ± 1.53) and Chlorella sp. (30.33 ± 1.15 mm). This stronger inhibitory activity was confirmed by the low MIC (6.25, 12.5 mg/L) and MAC (6.25, 12.5 mg/L) values. Furthermore, results showed different sensitivity between the prokaryotic and eukaryotic microalgae into MEA extracts. Based on the MIC and MAC values, we can distinguish two groups of plants. The first one, including M. spicatum, Ranunculus aquatilis, and Enteromorpha sp., can be considered as a preferable anti-prokaryotic group with a stronger inhibitory activity on M. aeruginosa growth. The second group, constituted by Potamogeton natans, Nasturtium officinale, Elodea sp., and Ceratophyllum sp., has a preferable and stronger inhibitory effect against eukaryotic algae (Chlorella sp.). Overall the results reveal the potential algicidal activity of macrophytes and suggested that MEA extracts could play an important role in biocontrol of HABs.

中文翻译：

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摩洛哥大型植物有机提取物的抗藻活性突出：在蓝藻水华控制中的潜在用途。

摘要

许多研究表明，大型植物产生的杀藻化合物对微藻类的有效性。这项研究的目的是评估七个摩洛哥大型植物乙酸乙酯提取物（MEA）的杀藻活性，以控制有害藻华（HABs）。强调了原核有毒蓝细菌（铜绿微囊藻）和真核微藻类（小球藻）的响应和敏感性。MEA提取物对两种微藻的杀藻作用通过纸盘扩散法和微稀释法进行了评估。为了评估最小抑菌浓度（MIC）和最小杀藻浓度（MAC），使用了最后一个。结果表明，所有MEA提取物均显着抑制了两种微藻的生长。鼠尾草有机提取物对铜绿假单胞菌和小球藻的生长抑制活性最高（35.33±1.53）。（30.33±1.15毫米）。低MIC（6.25，12.5 mg / L）和MAC（6.25，12.5 mg / L）值证实了这种较强的抑制活性。此外，结果表明，MEA提取物中原核和真核微藻的敏感性不同。基于MIC和MAC值，我们可以区分两组植物。第一个，包括sp.atum，毛an，和Enteromorpha sp。，可以被认为是对铜绿假单胞菌具有较强抑制活性的优选的原核生物基团。增长。第二组是由植物假单胞菌，金莲花，伊乐藻属和麦角藻组成，对真核藻类（小球藻）具有较好的抑制作用。总体而言，结果揭示了大型植物的潜在杀藻活性，并表明MEA提取物可能在HABs的生物防治中发挥重要作用。