Screening and mass-spectral confirmation of betalains in cactus pears
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The presence of betalain pigments in fruits ofOpuntia stricta, Opuntia undulata andOpuntia ficus-indica has been studied. Cultivars of deep red-purple colour, with high betacyanin content, were choosen for this investigation. The total betacyanin content was estimated spectrophotometrically E 1cm 1% =1120) and the results obtained indicated a higher betacyanin content inO. stricta (70 mg · 100 g−1 fresh fruit), than inO. undulata andO. ficus-indica (14–19 mg · 100 g−1 fresh fruit). Individual pigment analysis by HPLC with photodiode array detection revealed substantial differences between these species. In cactus pears fromO. stricta only betanin and isobetanin were detected. However, in cactus pears fromO. undulata andO. ficus-indica the predominant pigments were betanin and indicaxanthin, with very low levels of isobetanin. The identity of all these pigments was confirmed by mass-spectral analysis. The presence of neobetanin was not detected in fruits of any of the three species considered.
Key WordsColumn liquid chromatography Electrospray mass spectroscopy Betalains Cactaceae Opuntia
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- Piatelli, M. InChemistry and Biochemistry of Plant Pigments: Goodwin, T.W. Eds, Academic Press, London,1976.Google Scholar
- Strack, D.; Steglich, W.; Wray, V. InMethods in Plant Biochemistry (vol. 8): Dey, P.M.; Harborne, J.B. Eds, Academic Press, London,1993.Google Scholar
- Von Elbe, J.H.Food Technol. 1975,29, 42–46.Google Scholar
- Jackman, R.L.; Smith, J.L. InNatural Food Colorants, 2nd Ed.: Hendry, G.A.F.; Houghton, J.D. Eds., Blackie, London,1996.Google Scholar
- Odoux, E.; Domínguez-López, A.Fruits 1996,51, 61–78.Google Scholar
- Sobkowska, E.; Czapski, J.; Kaczmarek, R.Int. Food Ing. 1991,3, 24–28.Google Scholar
- Krifa, F.; Villet, A.; Roussel, A.M.; Alary, J.Ann. Fals. Exp. Chim. 1987,928, 183–192.Google Scholar