Planta Med 2013; 79 - PI82
DOI: 10.1055/s-0033-1352171

Effect of gamma radiation in fractions end (8R,8'R,9S)-cubebin isolated from the alcoholic extract of the stem bark of Aristolochia esperanzae Kuntze

AG Pacheco 1, RT Nunes 1, AC Alcantara 2, D Pilo Veloso 2
  • 1Federal Institute for Education, Science and Technology in Southern Minas Gerais – Inconfidentes MG/Brazil
  • 2Federal University of Minas Gerais, Belo Horizonte MG/Brazil

The species Aristolochia esperanzae kuntze is found in Minas Gerais and used in the treatment of Rheumatoid Arthritis by the folk medicine of this region. The herbal drugs have a high level of microbiological contamination, and a alternative to increase the shelf life and reduce microbial contamination of herbal medicines is the gamma irradiation.

This paper describes the effect of gamma irradiation in fractions rich in flavonoids and saponins obtained from the alcoholic extract of the stem bark of the species as well as on the fitoconstituinte, (8R,8'R,9S)-cubebin (Fig. 1) isolated from the stem bark of A. esperanzae.1

Fig. 1: Structure of (8R, 8′R, 9S)-cubebin.

Sample 0.1 g of (8R,8'R,9S)-cubebin was submitted to gamma irradiation at a dose of 10 kGy. Samples subjected to gamma irradiation and unirradiated were analyzed by NMR. The 13C NMR spectra of (8R,8'R,9S)-cubebin showed different signals, which indicated the formation of radiolytic products after gamma irradiation.

The fractions rich in flavonoids and saponins were subjected to gamma radiation at a dose of 0.3 kGy to investigate the integrity front of the gamma irradiation. The irradiated and unirradiated materials was submitted to HPLC analyzes to investigate the effect of gamma irradiation. The chromatograms obtained by HPLC of fractions rich in flavonoids and saponins are shown in Fig. 2. Comparison of chromatograms obtained by HPLC analysis of these fractions indicates the integrity of the samples under the conditions considered.

Fig. 2: Comparison of chromatograms obtained by HPLC of fractions rich in flavanoids (a) and saponins (b), (non irradiated ––-; subjected to gamma radiation dose of 0.3 kGy –––; the chromatogram: UV detection at 370nm; chromatogram b: UV detection at 210nm (–––/––-) and 202nm (–––/–––).

Acknowledgements:

CNPq, UFMG, and IFSULDEMINAS

References:

[1] Pacheco, A. G.; Silva, T. M.; Manfrini, F. M.; Sallum, W. S. T.; Duarte, L. P.; Piló-Veloso, D.; Alcantara, A. F. C. Quim. Nova, 2010, 33, 91.

[2] Silva, T. M. Dissertação de Mestrado, 2010, Belo Horizonte, UFMG.