Analysis of Crocetins and Saffanal variations in Saffron(Crocus sativus) stigma samples and dietary supplements using HPLC-UHPLC-PDA-MS: Chemical profiling and chemometric analysis using LC-QToF

Authors: AVULA, BHARRATHI - University Of Mississippi; KATRAGUNTA, KUMAR - University Of Mississippi; WANG, YAN-HONG - University Of Mississippi; UPTON, ROY - American Herbal Pharmacop; KHAN, IKHLAS - University Of Mississippi

Submitted to: Food Analytical Methods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/15/2022
Publication Date: 4/9/2022
Citation: Avula, B., Katragunta, K., Wang, Y., Upton, R., Khan, I.A. 2022. Analysis of Crocetins and Saffanal variations in Saffron(Crocus sativus) stigma samples and dietary supplements using HPLC-UHPLC-PDA-MS: Chemical profiling and chemometric analysis using LC-QToF. Food Analytical Methods. https://doi.org/10.1007/s12161-022-02268-5.
DOI: https://doi.org/10.1007/s12161-022-02268-5

Interpretive Summary: Saffron, the most expensive spice in the world, is comprised of dried and dark red stigma of Crocus sativus L. flowers of the Iridaceae family. It is mainly used as a spice for imparting color, fragrance, and flavor to food but its medicinal and dyeing properties were also well known. In the United States (US), saffron products are used as dietary supplements for mood elevation, relaxation, weight loss, and to increase metabolism. The paper describes two analytical methods (HPLC and UHPLC) for the determination of crocetin esters, picrocrocin, safranal in saffron samples and dietary supplements for inclusion in a monograph under development by the American Herbal Pharmacopoeia (AHP). Twenty-nine dietary supplements were analyzed. Flower of Carthamus tinctorius (safflower) and fruit of Gardenia jasminoides were the main adulterants detected in dietary supplements. Summarily, 60 compounds, including five standards were tentatively identified from saffron stigma, style, and petal samples. Principle component analysis (PCA) was used to discriminate between saffron stigma samples and dietary supplements. The results indicated that commercial products are of variable quality and the analytical method is suitable for quality assessment of a variety of both raw material and finished dietary supplements. The methods developed were also applicable for detection of adulterated saffron samples.

Technical Abstract: Saffron, the most expensive spice in the world, is comprised of dried and dark red stigma of Crocus sativus L. flowers of the Iridaceae family. It is mainly used as a spice for imparting color, fragrance, and flavor to food but its medicinal and dyeing properties were also well known. In the United States (US), saffron products are used as dietary supplements for mood elevation, relaxation, weight loss, and to increase metabolism. The paper describes two analytical methods (HPLC and UHPLC) for the determination of crocetin esters, picrocrocin, safranal in saffron samples and dietary supplements for inclusion in a monograph under development by the American Herbal Pharmacopoeia (AHP). Method validation showed satisfactory results in linearity, precision and recovery. The limits of detection and limits of quantification were 10-50 ng/mL and 25-100 ng/mL, respectively. The content of picrocrocin, safranal and crocetin esters ranged from 0.6-10.2%, 0.02-0.22%, and 2.8-25.6%, respectively for thirty-seven stigma samples. Twenty-nine dietary supplements were analyzed. No saffron compounds were found in 16 (55%) of these products. Both methods showed similar analytical results with error of less than 0.3% and a quantitative deviation of less than 0.5%. The application of LC-QToF provided useful information to characterize compounds that can be tested to confirm or deny the presence of saffron stigma which may help to determine plant adulterants. Flower of Carthamus tinctorius (safflower) and fruit of Gardenia jasminoides were the main adulterants detected in dietary supplements. Summarily, 60 compounds, including five standards were tentatively identified from saffron stigma, style, and petal samples. Principle component analysis (PCA) was used to discriminate between saffron stigma samples and dietary supplements. The results indicated that commercial products are of variable quality and the analytical method is suitable for quality assessment of a variety of both raw material and finished dietary supplements. The methods developed were also applicable for detection of adulterated saffron samples.