Anacardic Acid Profiling in Cashew Nuts by Direct Coupling of Preparative High-Speed Countercurrent Chromatography and Mass Spectrometry (prepHSCCC-ESI-/APCI-MS/MS)

Abstract

In many subtropical and tropical countries the cashew nut production (Anacardium occidentale L., Anacardiaceae) is a valuable food crop and of high agroeconomical interest. Anacardic acids are phenolic lipids which have shown a wide spectrum of biological effects, such as antibacterial, and anti-tumor activities. In this preparative separation experiment high-speed countercurrent chromatography (HSCCC) was directly coupled to an electrospray and atmospheric pressure chemical ionization mass spectrometry device (prepHSCCC/ESI-APCI-MS-MS) and used as a metabolic profiling tool to investigate commercial cashew nuts for the occurrence and semiquantitative measurement of different anacardic acids. Immediate structural data were retrieved throughout the countercurrent chromatographic run. For higher and lower concentrated compounds all molecular ion signals and complete MS/MS-fragmentation data of anacardic acids were obtained. Twenty anacardic acids in the mass range between m/z 163 and m/z 657 were detected. Co-elution effects were monitored by selective mass traces and detection of novel minor concentrated anacardic acids with even numbered alkyl chains was achieved. Tentatative structures of novel dicarboxylic- and one dimeric anacardic acids will be presented.