Investigation of Organic Acids in Saffron Stigmas (Crocus sativus L.) Extract by Derivatization Method and Determination by GC/MS

Abstract

The beneficial health properties of organic acids make them target compounds in multiple studies. This is the reason why developing a simple and sensitive determination and investigation method of organic acids is a priority. In this study, an effective method has been established for the determination of organic (lactic, glycolic, and malic) acids in saffron stigmas. N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) was used as a derivatization reagent in gas chromatography combined with mass spectrometric detection (GC/MS). The saffron stigmas extract was evaporated to dryness with a stream of nitrogen gas. The derivatization procedure: 0.1 g of dried extract was diluted into 0.1 mL of tetrahydrofuran, then 0.1 mL MTBSTFA was orderly and successively added into a vial. Two different techniques were used to obtain the highest amount of organic acid derivatives from saffron stigmas. To the best of our knowledge, this is the first report of the quantitative and qualitative GC/MS detection of organic acids in saffron stigmas using MTBSTFA reagent, also comparing different derivatization conditions, such as time, temperature and the effect of reagent amount on derivatization process. The identification of these derivatives was performed via GC-electron impact ionization mass spectrometry in positive-ion detection mode. Under optimal conditions, excellent linearity for all organic acids was obtained with determination coefficients of R2 > 0.9955. The detection limits (LODs) and quantitation limits (LOQs) ranged from 0.317 to 0.410 µg/mL and 0.085 to 1.53 µg/mL, respectively. The results showed that the highest yield of organic acids was conducted by using 0.1 mL of MTBSTFA and derivatization method with a conventional heating process at 130 °C for 90 min. This method has been successfully applied to the quantitative analysis of organic acids in saffron stigmas.

Characterization of Phytochemical Components of Crocus sativus Leaves: A New Attractive By-Product

“…It was dissolved in a 200 µL mixture of acetonitrile and MTBSTFA (1:1), then heated in a glycerol bath and subjected to amino acid gas chromatography analysis. The gas chromatography method has been previously described by Mykhailenko et al [22] and Jarukas et al [23]. Briefly, the SHIMADZU GC-MS-QP2010 system and Rxi-5 ms (Restek Corporation, Bellefonte, PA, USA) capillary column (30 m, 0.25 mm outer diameter, 0.25 µm) were applied.…”

“…The derivatization procedure is highly dependent on the solvent used. Therefore, in our previous work [22,23], we developed the GC-MS method for organic acid investigation. Different times, temperatures and the effect of the reagent amount on the derivatization process were tested.…”

Determination of Organic Compounds, Fulvic Acid, Humic Acid, and Humin in Peat and Sapropel Alkaline Extracts

“…Derivatization and GC-MS analysis were performed according to the previous research about the analysis of organic compounds from natural sources [ 32 ].…”

Saffron (Crocus sativus L.): A Source of Nutrients for Health and for the Treatment of Neuropsychiatric and Age-Related Diseases

“…The chemical characteristics of saffron, which has been used as a medicinal plant and in cooking for millennia [ 10 ], reveal the presence of more than 150 volatile and non-volatile elements. This includes carotenoids, a few polyphenols and flavonoids and terpenes whose proportions may vary depending on the country of origin [ 7 , 11 , 12 , 13 , 14 , 15 ]. The approximate composition is well summarized in previous studies [ 1 , 7 , 12 ]: water (10%); proteins and amino acids (12%); lipids (5%); minerals (5%); fibers (5%); various sugars (63%); and vitamins (B1 (riboflavin), B2 (thiamine)).…”