Diagnosis of vitamin B1 deficiency is made bv -

Ans. is 'b' i.e., Transketolase activityo Thiamine diphosphate (TDP) or TPP is the coenzyme for three multienzyme complexes that catalyze oxidativedecarboxylation:Pyruvate dehydrogenaseQ in carbohydrate metabolism, which catalyzes the conversion of pyruvate to aceti CoAQ.a-Ketoglutarate dehydrogenaseQ in citric acid cycle, which catalyzes the conversion of a-ketoglutarate to succinyl CoAQ.Branched-chain keto acid dehydrogenaseQ which catalyzes the oxidative decarboxylation of branche chain keto amino acidsQ, i.e. leucine, isoleucine and valine.o Thiamine diphosphate is also the coenzume for transketolaseQ, in the pentose phosphate pathw ayQ. Therefon thiamine nutritional status is best assessed by erythrocyte (preferredQ) or w hole blood transketolase activity Q.