High light is beneficial for purple non-sulfur bacteria (PNSB) growth. However, excessive light causes photoinhibition. In this novel study, flashing light was used to alleviate photoinhibition and promote biomass growth in PNSB wastewater treatment. Results showed that flashing light effectively increased biomass production. The highest biomass concentration (2688.8 mg/L) and chemical oxygen demand removal (in 177 μmol/m²/s-0.75 duty cycle-1000 Hz group) were 41.5% and 28.4% higher than that in the constant stress light group (same incident light). This group also increased biomass concentration by 21.3% and reduced energy consumption by 26.2% compared with the constant normal light group (same energy input). The shortened single light provision time of flashing light increased the relative electron transportation rate by 116.6%, avoiding photoinhibition, promoting energy utilisation, and enhancing substance synthesis. Flashing light can be used as a light regulation strategy to enhance biomass accumulation and reduce energy consumption in PNSB-based industries.

高光有利于紫色非硫细菌 (PNSB) 的生长。然而，过多的光会导致光抑制。在这项新颖的研究中，闪光灯用于减轻光抑制并促进 PNSB 废水处理中的生物量增长。结果表明，闪光灯有效地增加了生物质产量。最高的生物量浓度 (2688.8 mg/L) 和化学需氧量去除 (177 μmol/m ²/s-0.75 占空比-1000 Hz 组）分别比恒应力灯组（相同入射光）高 41.5% 和 28.4%。该组与恒定常光组（相同能量输入）相比，生物质浓度也提高了21.3%，能耗降低了26.2%。闪光灯单光提供时间的缩短使相对电子传输率提高了116.6%，避免了光抑制，促进了能量利用，增强了物质合成。闪光灯可用作光调节策略，以增强基于 PNSB 的行业的生物质积累和减少能源消耗。