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Facile NMR approach for profiling curcuminoids present in turmeric
Aishwarya Praveen1, Durga Prasad2, Soumya Mishra2
1Department of Spice and Flavour Science, Council of Scientific and Industrial Research - Central Food Technological Research Institute, Mysuru, Karnataka 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Food Chemistry
|November 24, 2020
Summary
A new 1H NMR method simplifies curcuminoid analysis in turmeric. This technique accurately quantifies curcumin, demethoxycurcumin, and bisdemethoxycurcumin across different regions.
Area of Science:
- Phytochemistry
- Analytical Chemistry
Background:
- Turmeric contains curcuminoids like curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC).
- Traditional analysis methods (UV-Vis, HPLC, LC-MS) can be time-consuming and complex.
Purpose of the Study:
- To develop a simplified, time-efficient method for curcuminoid analysis.
- To apply a 1H NMR-based approach for quantifying curcuminoids from various geographical sources.
Main Methods:
- A novel sample preparation protocol for simultaneous curcuminoid determination using 1H NMR.
- Quantification utilizing the 6-7 ppm vinylic proton region in the 1H NMR spectrum.
- Acetone identified as an optimal solvent for solubility and spectral resolution.
Main Results:
- Curcumin was the predominant curcuminoid (46.8-59.50%) in most samples.
- Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) levels varied, with BDMC exceeding DMC in the Andhra Pradesh variety.
- Results were corroborated by High-Performance Liquid Chromatography (HPLC) analysis.
Conclusions:
- 1H NMR offers a viable, efficient alternative for curcuminoid quantification.
- The developed method demonstrates applicability across different turmeric geographical varieties.
- This approach enhances analytical productivity and simplicity for curcuminoid profiling.
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