Institution: | 1. The School of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK;2. Chemistry Department, College of Science, UAE University, 15551 Al-Ain, United Arab Emirates;3. Chemical Engineering Department, College of Engineering, UAE University, 15551 Al-Ain, United Arab Emirates |
Abstract: | BackgroundIn recent years, microalgae (MA) have attracted much interest considering their possible therapeutic application. They contain active natural compounds or derivatives (extracts, pure or chemically modified compounds) that have increasing applications in the pharmaceutical industry.MethodsThe present study aims to examine microalgae for new photosensitizers, with a potential to be used in the light-associated treatment of tumors. Semi-purified extracts of several microalgae strains were evaluated as photosensitizers for photodynamic therapy (PDT) applications. Four tumor cell lines (A549, LNCap, MCF-7, and MDA-MB 435) were used to assess 34 samples extracted by three methods: cellulase enzyme, lysozyme enzyme and ultra-sonication. The fluorescence measurements and the recorded images alongside the spectral intensities between 650–800 nm wavelengths provided characteristic features to some of the contents of the examined extracts.ResultsSeveral microalgae constituents activated by blue light (BL), red light (RL) or both (in sequence) exhibited significant effects on the viability of the tumor cell lines, decreasing it as much as 95% for certain MA constituents. Majority of the MA constituents showed a higher phototoxicity after exposure to both blue and red lights than the photo-induced toxicity when exposed to a single light source. The viability of the tumor cells exhibited the dose dependent response with the MA constituents.ConclusionThe results clearly showed that MA constituents are potential photosensitizers that have a significant photo-damage effects on the tested cancer cells. |