Evaluation of thermo sensitivity of curcumin and quantification of ferulic acid and vanillin as degradation products by a validated HPTLC method.

Charismatic therapeutic potential of curcumin in biological research have triggered an interest to explore the thermal degradation pattern of curcumin, formation of ferulic acid and vanillin as degraded metabolites at different temperatures in methanol and corn oil. The results revealed 47% w/w loss of curcumin along with formation of 17% w/w vanillin and 9% w/w ferulic acid at boiling temperature of methanol while oil samples show 38.9% w/w loss of curcumin but not confirming the formation of ferulic acid and vanillin. Findings of this study revealed that formation of vanillin in methanol starts around 50°C and its concentration goes on increasing up to 70°C and then further degraded at boiling temperature of methanol. Formation of ferulic acid begins around 60°C and initially increases with rise of temperature and then decreases approaching boiling point of methanol. Vanillin as well as ferulic acid was absent in corn oil samples though degradation of curcumin was observed by reduction in peak area of curcumin. The present study was done by applying a validated high-performance thin-layer chromatography method. The method involved glass-backed HPTLC plates precoated with silica gel 60F254 as the stationary phase and toluene: ethyl acetate: methanol (8:1:1, v/v/v) as mobile phase.