A HPTLC method for the quantitative determination of Piperine and Capsaicin in Rasam, A South Indian spice soup

Abstract

Rasam is a popular spice soup of South Indian traditional food. Rasam is prepared traditionally by incorporating spcies such as turmeric, coriander, black pepper, garlic, chili pepper, curry leaves, cumin, mustard, and asafoetida in tamarind juice. All ingredients used in the preparation of rasam are known for various medicinal uses which, makes rasam a traditional food with a lot of functional ingredients. There are reports to suggests that a regular chronic consumption of traditional foods with functional ingredients may prevent numerous diseases. There was no scientific literature available on the phytochemical composition of rasam. We, herein aim to estimate the quantity of piperine and capsaicin present in the standardized rasam by HPTLC method. Rasam was prepared as per reported method and the sample solution was prepared by extracting rasam with diethyl ether. The mobile phase used was toluene: ethyl acetate (7:3, v/v). Densitometric scanning was performed in absorption-reflection mode at at 527 nm. Linear range was 1 to 5 μg for both piperine and capsaicin. The amount of piperine and capsaicin from the standardized rasam was found to be 0.234 and 0.335 % w/v respectively. This TLC procedure may be used effectively for identity, quality evaluation as well as quantitative determination for piperine and capsaicin in rasam.