Quantitative Analysis of capsaicin in Capsicum frutescens L. by 1HNMR

Capsicum frutescens L . also known as red chilli, is a member of Solanaceae family and used in folk medicine for the treatment of rheumatoid arthritis, osteoarthritis and neuropathies [1]. In order to develop an efficient laboratory scale extraction of capsaicin from red chilli different methods have been compared. Ultrasonication, microwave assisted extraction and Soxhlet extraction methods were evaluated for their efficiencies and 1 H-NMR spectrometry was applied to the analysis of the capsaicin in extracts without chromatographic purification. In the 1 H-NMR spectrum integration range of peak 4.349–4.360 ppm was chosen for quantitative analysis. These integrals were compared to integrated value of dimethyl formamide as an internal standard at the range of 8.006–8.030 ppm. Among the tested methods microwave showed the highest yield of capsaicin (0.67%) compared to ultrasonic extraction (0.53%) and conventional Soxhlet method (0.4%). Acknowledgements: We are sincerely grateful for financial support by Research and Technology Deputy of ACECR under the contract No. 982–11. References: [1] Al-Qarawi A., Adam, E. (2003) Phytother. Res. 17: 92–95.