Fermentation engineering 下游工程 DOWNSTREAM PROCESSES product extraction, purification assay waste treatment FERMENTATION Process Control by product recovery The ratio of recovery to fermentation costs for L-asparaginase: 3.0 ethanol: 0.16DOWNSTREAM PROCESSES - product extraction, purification & assay - waste treatment -by product recovery FERMENTATION Process Control 下游工程 The ratio of recovery to fermentation costs for L-asparaginase: 3.0 ethanol: 0.16 Fermentation engineering