Related Experiment Video
Updated: May 29, 2026
Improved UPLC-UV Method for the Quantification of Vitamin C in Lettuce Varieties (Lactuca sativa L.) and Crop Wild Relatives (Lactuca spp.)
Published on: June 30, 2020
A validated Fourier transform infrared spectroscopy method for quantification of total lactones in Inula racemosa and
Garg Shivali1, Lahorkar Praful, Gadgil Vijay
1Department of Phytochemistry, Unilever R&D Bangalore, 64 Main Road Whitefield, Bangalore 560066, India. shivali.garg@unilever.com
Introduction:
Fourier transform infrared (FT-IR) spectroscopy is a technique widely used for detection and quantification of various chemical moieties. This paper describes the use of the FT-IR spectroscopy technique for the quantification of total lactones present in Inula racemosa and Andrographis paniculata.
Objective:
To validate the FT-IR spectroscopy method for quantification of total lactones in I. racemosa and A. paniculata.
Methodology:
Dried and powdered I. racemosa roots and A. paniculata plant were extracted with ethanol and dried to remove ethanol completely. The ethanol extract was analysed in a KBr pellet by FT-IR spectroscopy. The FT-IR spectroscopy method was validated and compared with a known spectrophotometric method for quantification of lactones in A. paniculata.
Results:
By FT-IR spectroscopy, the amount of total lactones was found to be 2.12 ± 0.47% (n = 3) in I. racemosa and 8.65 ± 0.51% (n = 3) in A. paniculata. The method showed comparable results with a known spectrophotometric method used for quantification of such lactones: 8.42 ± 0.36% (n = 3) in A. paniculata. Limits of detection and quantification for isoallantolactone were 1 µg and 10 µg respectively; for andrographolide they were 1.5 µg and 15 µg respectively. Recoveries were over 98%, with good intra- and interday repeatability: RSD ≤ 2%.
Conclusion:
The FT-IR spectroscopy method proved linear, accurate, precise and specific, with low limits of detection and quantification, for estimation of total lactones, and is less tedious than the UV spectrophotometric method for the compounds tested. This validated FT-IR spectroscopy method is readily applicable for the quality control of I. racemosa and A. paniculata.
