MICROBIAL BIOSENSOR SYSTEM FOR RAPID-DETERMINATION OF VITAMIN-B-6

A microbial biosensor system was based on an immobilized microorganism (Saccharomyces uvarum 4288 ATCC9080) and Clark-type oxygen electrode consisting of a platinum cathode, lead anode, alkaline electrolyte, an d an oxygen permeable Teflon membrane. The determination was based on the respiratory activity of the microorganism in presence of vitamin B -6. Optimum conditions were: concentration of immobilized cells on mem brane: OD660 = 0.05, temperature: 30 degrees C. When oxygen permeable Teflon membranes (0.5 mil and 2.0 mil) were employed, relationships be tween vitamin B-6 (pyridoxine) and current decrease were linear in the range of 0.5 ng/mL-2.5 ng/mL. and 2.5 ng/mL-12.5 ng/mL, respectively. One assay could be completed within 15 min. This system provided rapi d and simple determinations of vitamin B-6 in marine products with goo d correlation to traditional microbial assay values.