Leaf protein was separated by heat coagulation (80 degrees C) from leaf juices of four cruciferous plants: turnip (Brassica campestris L.), mustard (Brassica nigra Koch.), radish (Raphanus sativus L.) and cauliflower (Brassica oleracea L. var botrytis). Three yeasts, Saccharomyces cerevisiae, Torula utilis and Candida lipolytica, were grown in deproteinized leaf juices (DW) of these plants. The yeast cells produced in these wheys were found to be rich in protein and vitamins. The chemical oxygen demand (COD) and biological oxygen demand (BOD) values of DW samples were reduced significantly by the growth of yeasts. Copyright (C) 1996 Elsevier Science Ltd.