Biofuels are the most awaited products of scientific research. The fossil fuels are being exhausted, and pollution is increasing globally. Algal biofuels are one of the promising options. They are wonderful tiny factories that yield a variety of substances that have the property to act as sources of ecofriendly fuels. More attention has been focused on microalgae-derived biomass for generating diverse renewable energy sources. The distinct features that microalgae possess include high biomass yield, abundant oil content, no requirement for land and easy cultivation in wastewaters coupled with carbon dioxide mitigation. Microalgae are tiny reservoirs of a plethora of biofuels. The diverse algal biofuels range from biodiesel, straight vegetable oil (SVO), lipids, ethanol and hydrogen. Biofuels are the need of today, and researchers around the globe are exploring the options for biological fuel production.

β-glucan has been shown to be effective for several diseases such as immune regulation and blood pressure suppression. Seaweed contains a β-1,3/1,6-glucan called laminaran. The present commercial source of β-glucan is black yeast; however, a fermentation process using organic carbon substrates makes production unsustainable, whereas macroalgae provide a sustainable alternative with the use of CO₂ and seawater as growth substrates. However, bioactivity studies on laminaran are limited. We aimed to evaluate whether laminaran can scavenge reactive oxygen species (ROS) and attenuate cytotoxicity caused by clinical drugs such as indomethacin (Ind) and dabigatran (Dab). Electron spin resonance assay revealed that laminaran scavenged singlet oxygen (¹O₂) and superoxide anions (O₂^•−) directly but did not scavenge hydroxyl radicals (^•OH). Mitochondrial ROS detection dye showed that laminaran scavenged mitochondrial O₂^•− produced upon administration of Ind or Dab. Moreover, significant reductions in ^•OH and peroxynitrate (ONOO⁻) levels were observed. Since ^•OH and ONOO⁻ are generated from O₂^•− in the cells, laminaran could indirectly suppress the generation of ^•OH and ONOO⁻ via the removal of O₂^•−. Both Ind and Dab induce cell injury via ROS production. Laminaran attenuated the cytotoxicity derived from these drugs and may represent a functional food with anti-aging and disease prevention properties.