Probing Anthocyanin Profiles in Purple Sweet Potato Cell Line (Ipomoea batatas L. Cv. Ayamurasaki) by High-Performance Liquid Chromatography and Electrospray Ionization Tandem Mass Spectrometry

Abstract

A purple line cell line (PL) generated from the storage root of purple-fleshed sweet potato (Ipomoea batatas L.) cv. Ayamurasaki produces a complex mixture of anthocyanins, and seven major anthocyanins have been isolated and identified to date. All these anthocyanins are exclusively cyanidin or peonidin 3-sophoroside-5-glucosides and their acylated derivatives. High-performance liquid chromatography (HPLC) coupled to photodiode array (PDA) detection and electrospray ionization tandem mass spectrometry (ESI-MS/MS) on a triple quadrupole instrument was employed to further investigate the anthocyanin composition of the PL extract. Precursor-ion analysis, product-ion analysis, and selected reaction monitoring (SRM) MS/MS experiments were conducted sequentially to screen and characterize anthocyanins in the aqueous extract of the PL cell line. Precursor-ion analysis specifically detected the molecular cations of each category of anthocyanins by scanning the precursors of anthocyanidins (cyanidin, peonidin, and pelargonidin). The detected molecular cation of each anthocyanin was fragmented using product-ion analysis by collisionally activated dissociation (CAD). MS/MS using SRM detection was conducted to further confirm the fragmentation observed during product-ion analysis. In comparison to the commonly used product-ion analysis technique, the combined use of precursor-ion analysis, product-ion analysis, and SRM is particularly useful for positive identification of anthocyanins in complex matrixes and provides important information to confirm the proposed structures. Twenty-six anthocyanins were detected and characterized in the aqueous extract of the PL cell line. Several anthocyanins, including two pelargonidin derivatives, were tentatively identified for the first time in these cells.

Biotransformation of anthocyanins from two purple-fleshed sweet potato accessions in a dynamic gastrointestinal system

“…This anthocyanin has been measured in both uncooked (Montilla et al, 2010) and cooked purple sweet potatoes (Truong et al, 2010) and was the most thermally stable anthocyanin associated with protection against a colorectal cancer model from intake of PFSP . This latter anthocyanin can be digested via deglycosylation to form cyanidin 3-p-hydroxy-benzoyl-sophoroside (m/z 731) (M (893)-162 for the loss of glucose) (Tian, Konczak, & Schwartz, 2005), which was detected in all five sections of the gut model with PM09.812 and in the V2-V5 vessels of PM09.960.…”

An analytical pipeline to compare and characterise the anthocyanin antioxidant activities of purple sweet potato cultivars

“…The chromatographic conditions were optimised to generate a complete separation of all main peaks, which exhibited typical anthocyanin spectral profiles, with a maximum absorbance at 520-530 nm (Tian, Konczak, & Schwartz, 2005;Truong et al, 2010). The reference chromatographic fingerprint (Fig.…”

Composition and color stability of anthocyanin-based extract from purple sweet potato

“…Fan et al (2008) proved that the anthocyanins in purple sweet potato are mainly cyanidin and peonidin which are glycosylated with sugars. Tian et al (2005) indicated that the glycosylated anthocyanins are commonly mono-or di-acylated with caffeic, ferulic and hydroxybenzoic acids. This structure complication leads to a big challenge to the identification of PSPAs.…”