Off-line ESI-MS/MS profiling of betalains and flavonoid glycosides isolated from (fruit) Opuntia stricta var. dillenii and (vegetable) Atriplex hortensis var. rubra by countercurrent chromatography

Thi Minh Thu Tran^{1, 2*}, Thanh Binh Nguyen¹, Peter Winterhalter¹, Gerold Jerz¹

¹Institute of Food Chemistry, Technische Universität Braunschweig, Germany

²Faculty of Biotechnology, Chemical Engineering and Food Technology,

Can Tho University of Technology, Vietnam

Received 23 December 2020; accepted 19 March 2021

 

Abstract:

Opuntia stricta var. dillenii and Atriplex hortensis var. rubra, two plant species with abundant betalain and flavonoid content, were studied by high performance countercurrent chromatography (HPCCC) coupled with ESI-MS/MS in an off-line detection process. Both CCC runs used tert.-butyl-methyl-ether/n-butanol/acetonitrile/water 1% trifluoroacetic acid (v/v/v/v, 2:2:1:5) as a biphasic solvent system within an elution-extrusion mode. The resulting fractions were scanned by an off-line sequential injection to ESI-MS/MS approach. The separation of Opuntia stricta var. dillenii extract showed a partial isolation of principal betalains (betanin) from their derivatives (betanidin, phyllocactin, feruloyl-betanin, betaxanthin), degraded products (hydroxyl-neobetanin, mono decarboxy-betanins), and flavonoid glycosides (isorhamnetin-rutinoside, kaempferol-rutinoside). In case of Atriplex hortensis var. rubra, this study confirmed the coexistence of several flavonoids (quercetin-O-malonyl glucoside, kaempferol-O-malonyl glucoside) and generated few pure pigment fractions (celosianin II) for structural elucidation.

Keywords: Atriplex hortensis var. rubra, betalains, countercurrent chromatography (CCC), ESI-MS/MS, Opuntia stricta var. dillenii.

Classification number: 3.1