Comprehensive Effects of Flashing/Pulsed Light on Microalgae: Molecular Mechanisms and Biotechnological Applications

Abstract

Microalgae serve as a cell factory for sustainable biomass and high-value compound production, yet their industrial-scale cultivation is often constrained by light energy utilization. The continuous illumination often limits photosynthetic efficiency and biomass and high-value compound productivity due to a kinetic mismatch between rapid photochemical reactions (picosecond-to-millisecond scale) and slower downstream biochemical processes (like Calvin-Benson cycle). Flashing/pulsed light strategies mitigate these by delivering intermittent photons, exploiting the biological effects to enhance quantum yield, biomass productivity, and targeted metabolites accumulation. This mini review emphasizes historical development of core concepts, molecular mechanisms, Photosystem II (PSII) dynamics, plastoquinone buffering, temporal decoupling, parameter optimization, the applications in autotrophic and mixotrophic modes, and photobioreactor innovations. An updated timeline to date highlights the emerging AI-driven adaptive lighting systems that promise real-time optimization of flashing regimes. This review summarizes current understanding, critical knowledge gaps and future directions, particularly in intelligent control for scalable, energy-efficient cultivation of microalgae by the rational design of advanced photobioreactors and cultivation strategies.

Keywords

Microalgae / Flashing/pulsed light / Molecular mechanisms / Metabolic reprogramming / AIdriven adaptive lighting

Statement of the Use of Generative AI and AI-Assisted Technologies in the Writing Process

During the preparation of this manuscript, the authors used DeepSeek-V4 to assist with preliminary language polishing. The authors have thoroughly reviewed and revised all content generated or suggested by the tool and assume full responsibility for the accuracy, originality, and scientific integrity of the published work.

Author Contributions

B.W.: Writing—Original Draft, Literature Search/Data Curation; D.W.: Writing—Review & Editing, Supervision and Funding Acquisition.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The datasets generated during the current study are available from the corresponding author on reasonable request.

Funding

This work was supported by National Key Research and Development Program for Food Nutrition and Safety (2023YFF1104100), and the Key Project of Guangzhou Research & Development Program (2025B03J0093).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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