Parameter Analysis by Electron Spin Resonance Spectroscopy of Cellulose Radicals in Gamma-irradiated Dried Spicy Vegetables

방사선 조사 건조향신료의 ESR 측정에서 Cellulose Radical의 Parameter 분석

  • Ahn, Jae-Jun (Department of Food Science & Technology, Kyungpook National University) ;
  • Kim, Dong-Gil (Department of Food Science & Technology, Kyungpook National University) ;
  • Chung, Hyung-Wook (Korea Food and Drug Administration) ;
  • Kwon, Joong-Ho (Department of Food Science & Technology, Kyungpook National University)
  • Published : 2009.06.30

Abstract

Electron spin resonance (ESR) spectroscopy was used to detect radiation-induced signals from irradiated spices and ESR parameters were analyzed to define specific signals. Four powdered spices (red pepper, garlic, onion, and black pepper) were irradiated with 0, 1, 5, or 10 kGy at room temperature using a [60Co] gamma-ray irradiator prior to ESR analysis. Radiation-induced triplet signals, including those from the cellulose radical, which are center signals ($g_2=2.00673$) within the range of 3.0455 mT, were observed in all irradiated spice samples. The parameters g-value, center field, and signal range of hyperfine triplet ESR signals were constant in all irradiated samples, being specific for cellulose radicals and thereby distinguishing these signals from those of nonirradiated control samples. High positive correlation coefficients ($R^2=0.8452-0.9854$) were obtained between irradiation doses and corresponding ESR signal intensities. Thus, reliable detection of irradiated dried spices by measurement of ESR cellulose signals was confirmed by parameter analysis for the cellulose radical.

ESR spectroscopy에 의한 방사선 조사 건조향신료의 조사여부의 정확한 판별에 필요한 기초자료를 얻고자 방사선 조사 유래의 cellulose radical에 대한 parameter를 분석하였다. 건조향신료 분말 4종(고추, 마늘, 양파, 후추)에 대하여 0, 1, 5, 10 kGy의 $^{60}Co$ 감마선을 조사한 후 ESR signal을 분석하였다. 방사선 조사된 4종의 건조향신료는 모두 방사선 조사 유래의 triplet signal인 cellulose radical을 나타내면서 center signal($g_2=2.00673$)은 좌우 3.0455 mT 간격의 특이적인 signal을 보였다. 조사시료에서 나타난 hyperfine triplet signal(cellulose radical)의 g-value, center field 및 저-고자장 signal의 간격은 조사선량이 변화하여도 일정하였으므로 이들 parameter들은 cellulose radical의 고유 특성임을 확인 하였다. 이로써 감마선 조사시료와 비조사 시료 간의 구별이 분명하였다. ESR signal intensity는 조사선량이 증가함에 따라 유의적으로 증가하였다($R^2=0.8452{\sim}0.9854$). 이상의 결과에서 cellulose radical의 parameter 분석은 건조향신료의 ESR 분석에서 조사여부의 판별에 대한 신뢰성을 뒷받침 해 주었다.

Keywords

References

  1. IAEA. (2008) International Atomic Energy Agency homepage, http://nucleus.iaea.org/NUCLEUS/nucleus/Content/Applications/FICdb/FoodIrradationclearances.jsp?module=cif. Accessed on July 5
  2. KFDA. (2008) Korea Food Standard Code. Korea Food & Drug Administration, p.2-1-9~2-1-10
  3. FAO/WHO CODEX STAN. (2003) General Codex Methods for The Detection of Irradiated Foods, CODEX STAN 231-2001, Rev.1
  4. Desrosiers, M.F. (1996) Current status of the EPR method to detect irradiated food. Appl. Radiat. Isotopes, 47, 1621-1628 https://doi.org/10.1016/S0969-8043(96)00255-2
  5. Raffi, J., Agnel, J.P.L., Buscarlet, L.A. and Martin, C.C. (1988) Electron spin resonance identification of irradiated strawberries, J. Chem. Soc. Faraday T., 184, 3359-3362
  6. Desrosiers, M.F., Le, F.G. and McLaughlin, W.L. (1989) Examination of gamma-irradiated fruits and vegetables by electron spin spectroscopy. J. Agric. Food Chem., 34, 895-898 https://doi.org/10.1021/jf00071a032
  7. Helle, N., Linke, B., B$\ddot{o}$gl, K.W., and Schreiber, G.A. (1992) Elektronen-spin- resonanz-spektroskopie an Gew$\ddot{u}$rzproben. Nachweis einer Behanlung mit Ionisierenden Strahlen. Z. Lebensm. Unters. For., 195, 129-132 https://doi.org/10.1007/BF01201772
  8. Raffi, J., Yordanov, N.D., Chabane, S., Douifi, L., Gancheva, V. and Ivanova, S. (2000) Identification of irradiation treatment of aromatic herbs, spices and fruit by electron paramagnetic resonance and thermoluminescence Spectrochim. Acta A, 56, 409-416 https://doi.org/10.1016/S1386-1425(99)00252-8
  9. Stevenson, M.H. and Gray, R. (1995) The use of ESR spectroscopy for the identification of irradiated food. Annual Reports on NMR Spectroscopy, 31, 123-142 https://doi.org/10.1016/S0066-4103(08)60146-5
  10. Origin (1999) Origin Tutorial Manual, version 6.0, Microcal Software, Inc., Northampton, MA., U.K., p.20-45
  11. SAS (1998) SAS User`s Guide Statistics, 3th ed., Statistical Analysis System Institute Inc., Cary, NC, U.S.A.
  12. Raffi. J.J. (1998) Identifying irradiated foods. Trac-Trend. Anal. Chem., 17, 226-233 https://doi.org/10.1016/S0165-9936(98)00012-0
  13. Johnston, D.E. and Stevenson, M.H. (1990) Food Irradiation and the Chemist. Royal Society of Chemistry, Cambridge, U.K. p.89-90
  14. CEN. (2000) Detection of irradiated food irradiated food containing cellulose, method by ESR spectroscopy. European Committee for Standard. English version of EN 1787, Brussels, Belgium
  15. Raffi, R. and Agnel, J.P.L. (1989) Electron spin resonance identification of irradiated fruits. Radiat. Phys. Chem., 34, 891-894
  16. De Jesus, E.F.O., Rossi, A.M. and Lopes R.T. (2000) Identification and dose determination using ESR measurements in the flesh of irradiated vegetables products. Appl. Radiat. Isotopes, 52, 1375-1383 https://doi.org/10.1016/S0969-8043(00)00098-1
  17. Deighton, N., Glidwell, S.M., Goodman, B.A. and Morrison, I.M. (1993) Electron paramagnetic resonance of gamma-irradiated cellulose and lignocellulosic material. Int. J. Food Sci. Tech., 28, 45-55 https://doi.org/10.1111/j.1365-2621.1993.tb01250.x
  18. Bayram, G. and Delinceé, H. (2004) Identification of irradiated Turkish foodstuffs combining various physical detection methods. Food Control, 15, 81-91 https://doi.org/10.1016/S0956-7135(03)00018-5
  19. Desrosiers, M.F., Yacko, D.M., Basi, A. and McLaughlin, W.L. (1996) Interlaboratory trials of the EPR method for the detection of irradiated spices, nutshell and eggshell. In Detection methods for irradiated foodscurrent status, McMurray, C.H., Stewart, E.M., Gray, R. and Pearce, J.(Editors), Royal Society of Chemistry, Cambridge, U.K., p.108-118
  20. Nam, H.S., Suh, C.S. and Yang, J.S. (2001) Identification of gamma-irradiated teas by ESR spectroscopy. Food Sci. Biotechnol., 10, 602-605
  21. Abdel-Fattah, A.A. (2002) Identification and dose assessment of irradiated cumin by EPR spectrometry. Appl. Radiat. Isotopes, 56, 557-562 https://doi.org/10.1016/S0969-8043(01)00246-9