Measurement of actual electron transport system (ETS) activity in marine sediments by incubation with INT

Abstract

A modification of the TREVORS's method (1982) for measuring actual Electron Transport System Activity (aETSA) by 2‐(p‐iodophenyl)‐3‐(p‐nitrophenyl)‐5‐phenyl tetrazolium chloride (INT) reduction to INT‐formazan is presented. A major modification is the determination of the INT chemical reduction by reductor compounds in samples. The molar extinction coefficient of INT‐Formazan in methanol was found to be 18000 M^‐1.cm^‐1. Comparisons with O₂ consumption rates and ETS activities were established for microbial cultures and sediments.