Among the essential conditions for growing microalgae are the type of light radiation an‎d the composition of the culture medium used. Any change in these conditions directly affects parameters such as density, specific growth, doubling time an‎d biomass production. In this study, the combined effect of fluorescent lights an‎d red LED light in a culture medium enriched with alcohol factory wastewater at concentrations of 0.5 an‎d 1.5 (in the preliminary stage) an‎d at two concentrations of 1 an‎d 5 in the main stage in a culture medium enriched with alcohol factory wastewater in the algae Scenedesmus quadricauda has been investigated. The experiment was carried out in a completely ran‎domized design with three replications in BBM culture medium for two periods of 13 days. During the cultivation period, cell density, specific growth rate, algal biomass, chlorophyll a an‎d fatty acids were measured. The highest amount of chlorophyll a was observed in the preliminary stage in the fluorescent light treatment with 0.5% effluent (ALF0.5)2.10mg/l an‎d the lowest amount 0.44mg/l in the control treatments, the highest amount of chlorophyll a was obtained in the main stage in the fluorescent light control treatment (BBMF) an‎d the lowest amount in the fluorescent light treatment with 5% effluent (ALF5). The amount of chlorophyll a in the main stage in all LED light treatments was higher than in the control treatment with the same light an‎d in all fluorescent light treatments was lower than in the control treatment with the same light. The highest biomass in the preliminary stage was obtained in the LED light treatment with 1.5% effluent (ALL1.5) an‎d the lowest biomass in the LED control treatment. The highest biomass in the main stage was obtained in the LED light treatment with 5% effluent (ALL5) an‎d the lowest biomass in the LED control treatment. The biomass production in both stages of the experiment was increasing with increasing alcohol effluent concentration. The highest amount of saturated fatty acid (SFA) was measured in the fluorescent light control treatment (BBMF), the highest amount of monounsaturated fatty acid (MUFA) in the fluorescent light treatment of 5% alcohol effluent (ALF5%), an‎d the highest amount of polyunsaturated fatty acid (PUFA) was measured in the LED light treatment of 1% alcohol effluent (ALL1%). The highest amount of SFA formed was related to C16:0, the highest amount of MUFA was related to C18:1, an‎d the highest amount of PUFA was related to C18:2. Keywords: Scenedesmus quadricaud, alcoholic wastewater, fluorescent light, red LED light, fatty acids

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عيسي ابراهيمي , اميرحسين جلالي