Figure 1 consists of two separate branches, which is the synthesis of thiazole and pyrimidine moieties. The condensation of pyrimidine and thiazole ring moieties will form thiamine monophosphate, which is then converted to the active form thiamine pyrophosphate (TPP). TPP is a cofactor of pyruvate dehydrogenase which participates in the oxidative decarboxylation of pyruvate to acetyl-CoA, synthesis of amino acid such as valine, leucine and isolecucine, 2-oxoglutarate dehydrogenase which is involved in Krebs cycle (Goyer, 2010;Goyer and Haynes, 2011; Tunc-Ozdemir et al., 2009). TPP is also a cofactor for transketolase in the oxidative pentose phosphate pathway, which plays a role in the production of reactive oxidative species (ROS). Downstream reactions of TPP-dependent of Krebs cycle is the oxidative phosphorylation pathway where electron is generated to synthesise ATP, which is important in energy production in all living organisms. Fundamentally, thiamine forms an indispensable role in proper functioning in plants. DOI: https://doi.org/10.21894/jopr.2017DOI: https://doi.org/10.21894/jopr. .2902 218