Thiamin status of a Melanesian population1 ’ 2

ABSTRACT A semiautomated method is described which uses the Abbott ABA-l00 bichro-matic analyzer to measure the stimulation of erythrocyte transketolase by thiamin pyrophosphate (the thiamin pyrophosphate effect). The method was accurate with a throughput of 30 samples per hour and is suitable for the study ofthe thiamin status oflarge populations. A significant proportion (21%) of a total of 1920 individuals of a predominantly Melanesian population were found to have an elevated thiamin pyrophosphate effect (greater than 15 % activation). This same proportion with an elevated thiamin pyrophosphate effect was found in an urban hospital patient group of 346 individuals. Statistical analysis indicated a significant inverse correlation between thiamin pyro-phosphate effect and plasma potassium concentration (p < 0.00 1). Analysis of human fecal samples for thiaminase I activity demonstrated that this enzyme was present in 23 of a total of 46 samples selected from both the Melanesian and urban hospital patient groups. Preliminary findings indicated that the thiaminase originated from a bacterial source. A m. J. Clin. Nutr. 34: 1584