Rapid green synthesis of gold nanocatalyst for high-efficiency degradation of quinclorac

•Porous chemical pretreated S. cerevisiae is used to synthesize Au nanocatalyst.•Increased glycosyl groups and enlarged cell wall pore accelerate Au NPs synthesis.•Spherical and mono-dispersed Au nanocatalyst can be green synthesized within 0.5h.•Au nanocatalyst exhibits good catalytic activity for dechlorination of quinclorac.