Quantitative determination of major alkaloids in Cinchona bark by Supercritical Fluid Chromatography

Abstract

Chinoline alkaloids found in Cinchona bark still play an important role in medicine, for example as anti-malarial and antiarrhythmic drugs. For the first time Supercritical Fluid Chromatography has been utilized for their separation. Six respective derivatives (dihydroquinidine, dihydroquinine, quinidine, quinine, cinchonine and cinchonidine) could be resolved in less than 7 min, and three of them quantified in crude plant extracts. The optimum stationary phase showed to be an Acquity UPC2 Torus DEA 1.7 µm column, the mobile phase comprised of CO2, acetonitrile, methanol and diethylamine. Method validation confirmed that the procedure is selective, accurate (recovery rates from 97.2% to 103.7%), precise (intra-day ≤2.2%, inter-day ≤3.0%) and linear (R2 ≥ 0.999); at 275 nm the observed detection limits were always below 2.5 µg/ml. In all of the samples analyzed cinchonine dominated (1.87%–2.30%), followed by quinine and cinchonidine. Their total content ranged from 4.75% to 5.20%. These values are in good agreement with published data, so that due to unmatched speed and environmental friendly character SFC is definitely an excellent alternative for the analysis of these important natural products.

Liquid chromatographic separation of alkaloids in herbal medicines: Current status and perspectives

“…Baseline separation of six analytes was obtained on the BEH 2EP column within 10 min. Quantitative determination of quinoline alkaloids from the barks of Cinchona pubescens Vahl, C. calisaya Weddell, C. ledgeriana Moens, and hybrids was also accomplished by SFC [95]. Additionally, a comparison study between SFC–DAD, HPLC–DAD–MS and GC–MS showed that SFC is an efficient method to separate the indole and oxindole alkaloids (including three pairs of diastereoisomers) from leaves of Mitragyna speciosa (Korth.)…”

Immunomodulators for Curtailing COVID-19: a Positive Approach

“…Many bioactive compounds derived from this bark are those of chinoline derivatives (cinchonine, quinine, cinchonidine, and quinidine). Others are their dihydro-derivatives [143]. Cinkona is also used for common cold, influenza, leg cramps etc.…”

Quantitative Analysis of Prenylated Constituents in Commercial Hops Samples Using Ultrahigh-Performance Supercritical Fluid Chromatography

“…Over the last few years, SFx-based techniques have become an interesting and powerful alternative in natural product analysis as they are applicable for both polar and nonpolar constituents [14][15][16][17]. SFx techniques can be divided into SFE [18], analytical SFC (e.g., UHPSFC [19][20][21]), and preparative SFC (prep-SFC) [22][23][24]).…”