Impact of nanoparticles in microalgal quantification: Advancements in enhancing biomass valorization and evaluating toxicity effects

Abstract

Microalgae, a photosynthetic unicellular microorganism, plays a prominent role in various applications. Recently, the integration of nanotechnology with microalgal biomass has received growing interest to enhance microalgal productivity and biomass valorization. Nanoparticles are known to regulate several cellular mechanisms and metabolic pathways in microalgae, thereby increasing biomass, lipids, carbohydrates, and other value added compounds. Moreover, it has observed that microalgal harvesting efficiency achieved up to >99 % by using nanoparticles as a catalyst, particularly magnetic nanoparticles. However, despite these advantages, nanoparticles at a certain concentrations and prolonged exposure can exhibit toxic effects such as oxidative stress, membrane damage, and others on microalgae. These toxicity activities may vary depending on the nanoparticle type, concentration, size, and exposure duration. Therefore, understanding the dual role of nanoparticles from both sides is crucial. This review provides a comprehensive overview of recent findings on nanoparticle-microalgae interactions, focusing on microalgal quantification, biomass valorization and toxicity mechanisms.