Algal-bacterial granules (ABGs) system represents a promising technology for organic wastewater treatment due to its high settleability, efficient oxygen transfer, and low-energy consumption. However, the secretion of extracellular polymeric substances (EPS) in algae, which played a key role in self-assembly of ABGs, would be inhibited by concentrated organic wastewater. This study proposed a novel strategy for developing ABGs by inducing bacterial N-acyl-homoserine lactone (AHL) variation through high-strength pyridine application. Results showed that bacterial long-chain AHL concentrations significantly increased in response to high-strength pyridine at 550 mg L