Review on Cryoprotectant Utilization in Grouper Sperm Cryopreservation

ABSTRACT Cryopreservation of fish sperm is a key technique for enhancing aquaculture productivity, maintaining genetic diversity, and ensuring reliable seed supply. This review highlights recent advances in cryoprotectants use, particularly, the synergistic roles of natural and synthetic cryoprotectants, including their interplay as permeating and nonpermeating agents, in optimizing sperm viability. Groupers ( Epinephelus spp.), important in Southeast Asian aquaculture, present challenges due to their protogynous hermaphroditism and limited sperm availability. This review discusses how cryoprotectants combinations such as DMSO with trehalose or sucrose improve membrane integrity, post‐thaw motility and fertilization outcomes. Natural cryoprotectants offer promising alternatives with reduced toxicity, though their mechanisms require further investigation. By comparing protocols across fish species, this review identifies knowledge gaps and proposes future directions for efficient cryopreservation in marine aquaculture.