1: With potassium dihydrogenphosphate; sulfuric acid; nicotinamide adenine dinucleotide; sodium formate; formate dehydrogenase in water T=31 - 37°C; pH=7.5; Enzymatic reaction; 2: With sodium hydroxide; L-lactic dehydrogenase type VIII in water T=33 - 38°C; pH=7.4; 18 h;