Production of the quinone-methide triterpene maytenin by in vitro adventitious roots of Peritassa campestris (Cambess.) A.C.Sm. (Celastraceae) and rapid detection and identification by APCI-IT-MS/MS

Abstract

Establishment of adventitious root cultures of Peritassa campestris (Celastraceae) was achieved from seed cotyledons cultured in semisolid Woody Plant Medium (WPM) supplemented with 2% sucrose, 0.01% PVP, and 4.0 mg L⁻¹ IBA. Culture period on accumulation of biomass and quinone-methide triterpene maytenin in adventitious root were investigated. The accumulation of maytenin in these roots was compared with its accumulation in the roots of seedlings grown in a greenhouse (one year old). A rapid detection and identification of maytenin by direct injection into an atmospheric-pressure chemical ionization ion trap tandem mass spectrometer (APCI-IT-MS/MS) were performed without prior chromatographic separation. In vitro, the greatest accumulation of biomass occurred within 60 days of culture. The highest level of maytenin--972.11 μ g·g⁻¹ dry weight--was detected at seven days of cultivation; this value was 5.55-fold higher than that found in the roots of seedlings grown in a greenhouse.

Figure 1

Initialization of in vitro adventitious roots of Peritassa campestris. (a) The seed coats being removed and the cotyledons being cut into explants; (b) seed cotyledon explants placed in WPM medium supplemented with 2% (w/v) sucrose, 0.01% (w/v) PVP, and 4.0 mg·L⁻¹ IBA; (c) adventitious roots after incubation in the dark for four weeks.

Figure 2

Seedling of Peritassa campestris grown in a greenhouse (one year old).

Figure 3

Adventitious root growth of P. campestris in dry weight and production of maytenin. The roots were cultivated for 105 days in WPM medium supplemented with 2% (w/v) sucrose, 0.01% (w/v) PVP, and 4.0 mg·L⁻¹ IBA under dark conditions.

Figure 4

Full APCI-IT-MS mass spectrum of the extract from the in vitro adventitious roots of Peritassa campestris obtained in the positive ion mode, normal mass scan, in the m/z range of 170–490.

Figure 5

Main fragmentation pathways observed in the positive ion mass spectrum of maytenin (adapted from [21]).

Figure 6

Spectrum of the [M + H]⁺ ion at m/z 421 of maytenin in the extract from in vitro adventitious roots of Peritassa campestris.