Fe[II], Cu[II] and Zn[II] chelating activity of buckwheat and buckwheat groats tannin fractions

• Autorzy: Karamac M.

Warianty tytułu

PL

Chelatowanie Fe[II], Cu[II] i Zn[II] przez frakcje taninowe z gryki i kaszy gryczanej

• Języki publikacji: EN

Abstrakty

EN

Phenolic compounds were extracted from buckwheat and buckwheat groats into 80% acetone (v/v). The crude extracts were separated with Sephadex LH-20 column chromatography into low molecular weight phenolic compounds and tannin fractions. The tannin fractions were characterised by colour reaction with vanillin/HCl reagent, ability for protein precipitation as well as SE-HPLC method. Chelation of Cu(II) and Zn(II) by tannin fractions was determined by reaction with tetramethylmurexide (TMM) whereas Fe(II) chelation was investigated by forming complexes with ferrozine. The tannin fractions obtained from buckwheat and buckwheat groats gave similar results in vanillin test; A500/mg was 1.04. Also results obtained using precipitation method were comparable. SE-HPLC chromatograms showed that in tannin fraction of buckwheat groats polymers with molecular weight ≥ tannic acid were present. On the chromatogram of buckwheat tannins peaks were shifted to lower molecular weight compounds. Tannins of buckwheat were stronger chelators of all metal ions tested (Fe(II), Cu(II) and Zn(II)) than tannins of buckwheat groats. Ions of copper were chelated the most effectively; 1 mg of buckwheat and buckwheat groats tannin fractions added per assay bound 86.0% and 72.9% of Cu(II), respectively. Buckwheat tannins used in the test at a level of 2.5 mg/assay bound approximately twice more Fe(II) than the same addition of buckwheat groats tannins. Zn(II) was chelated to the lowest extent, 17.2% was bound by buckwheat tannins and 13.5% by buckwheat groats tannins (5 mg of tannin/assay).

PL

Ekstrakty acetonowe z gryki i kaszy gryczanej rozdzielano na kolumnie wypełnionej żelem Sephadex LH-20 na frakcję niskocząsteczkowych związków fenolowych i taninową. Frakcje taninowe scharakteryzowano za pomocą reakcji z waniliną, zdolności do strącania białka oraz metodą SE-HPLC z zastosowaniem kolumny TSK Gel G2000SWXL (TosoHaas). Kompleksowanie jonów Cu(II) i Zn(II) przez taniny oznaczano w reakcji z tetrametylomureksydem (TMM). Chelatowanie Fe(II) badano wykorzystując reakcję barwną kompleksowania ferrozyny. Wyniki testu z waniliną przeprowadzonego z frakcjami taninowymi z gryki i kaszy gryczanej były podobne; wartość A500/mg wynosiła 1,04. Również w metodzie strąceniowej obie próby wykazały zbliżone do siebie rezultaty. Rozdział SE-HPLC tanin z kaszy gryczanej charakteryzował się obecnością polimerów o masach cząsteczkowych większych lub równych masie cząsteczkowej kwasu taninowego. Na chromatogramie frakcji taninowej z gryki piki były przesunięte w stronę mniejszych mas cząsteczkowych. Frakcja tanin z gryki wiązała więcej wszystkich testowanych jonów metali w porównaniu z frakcją tanin z kaszy gryczanej. Obie frakcje tanin najefektywniej chelatowały jony Cu(II). Frakcja tanin gryki dodana do próby w ilości 1 mg związała 86,0% jonów miedzi, natomiast frakcja z kaszy gryczanej – 72,9%. Dodatek 2,5 mg/próbę tanin gryki wiązał ponad dwa razy więcej jonów Fe(II), niż taka sama ilość tanin z kaszy gryczanej. Jony cynku były najsłabiej chelatowane. Frakcja tanin gryki (5 mg) kompleksowała 17,2% a tanin kaszy gryczanej – 13,5% jonów Zn(II).

Słowa kluczowe

EN

buckwheat; buckwheat groats; tannin fraction; nutritional quality; metal ion; chelation; tetramethylmurexide; ferrozine; phenolic compound

• Wydawca: -
• Czasopismo: Polish Journal of Food and Nutrition Sciences
• Rocznik: 2007
• Tom: 57
• Numer: 3
• Opis fizyczny: p.357-362,fig.,ref.

Twórcy

autor

Karamac M.

• Polish Academy of Sciences, Tuwima 10. 10-747 Olsztyn, Poland

Bibliografia

• 1. Amarowicz R., Piskuła M., Honke J., Rudnicka B., Troszyńska A., Kozłowska H., Extraction of phenolic compounds from lentil seeds (Lens culinaris) with various solvents. Pol. J. Food Nutr. Sci., 1995, 45, 53–62.
• 2. Amarowicz R., Troszyńska A., Karamać M., Antioxidant activity of plant extracts with high tannin content. Bromat. Chem, Toksykol. – Supl., 2005, 38, 193–195 (in Polish).
• 3. Asakura T., Nakamura Y., Inoue N., Murata M., Homma S., Characterization of zinc chelating compounds in instant coffee. Agric. Biol. Chem., 1990, 54, 855–862.
• 4. Borg D.C., Oxygen free radicals and tissue injury. 1993, in: Oxygen Free Radicals in Tissue Damage (eds. M. Tarr, F. Samson). Birkhauser, Boston, pp. 12–53.
• 5. Boyer R.F., McCleary, C.J., Superoxide ion as a primary reductant in ascorbate-mediated ferritin iron release. Free Rad. Biol. Med., 1987, 3, 389–395.
• 6. Eggum B.O., Kreft I., Javornik B., Chemical composition and protein quality of buckwheat (Fagopyrum eseulentum). Qual. Plant - Plant Foods Hum. Nutr., 1981, 30, 175–179.
• 7. Gulcin I., Kufrevioglu O.I., Oktay M., Buyukokuroglu M.E., Antioxidant, antimicrobial, antiulcer and analgesic activities of nettle (Urtica dioica L.). J. Ethnophar., 2004, 90, 205–215.
• 8. Hagerman A.E., Butler L.G., Protein precipitation method for the quantitative determination of tannins. J. Agric. Food Chem., 1978, 26, 809–812.
• 9. Hider R.C., Liu Z.D., Khodr H.H., Metal chelation of polyphenols. Methods Enzymol., 2001, 335, 190–203.
• 10. Holasova M., Fiedlerova V., Smrcinova H., Orsak M., Lachman J., Vavreinova S., Buckwheat - the source of antioxidant activity in functional foods. Food Res. Inter., 2002, 35, 207–211.
• 11. Karamać M., Pegg R.B., The limitation of the tetrametylmurexide method for investigation of Fe(II) chelation activity of phenolic compounds. J. Agric. Food Chem., 2007, submitted.
• 12. Khokhar S., Apenten R.K.O., Iron binding characteristics of phenolic compounds: some tentative structure – activity relations. Food Chem., 2003, 81, 133–140.
• 13. Lopes G.K.B., Schulman H.M., Hermes-Lima M., Polyphenol tannic acid inhibits hydroxyl radical formation from Fenton reaction by complexing ferrous ions. Bioch. Bioph. Acta., 1999, 1472, 142–152.
• 14. McDonald M., Mila I., Scalbert A., Precipitation of metal ions by plant polyphenols: optimal conditions and oridin of precipitation. J. Agric. Food Chem., 1996, 44, 599–606.
• 15. Mila I., Scalbert A., Expert, D., Iron withholding by plant polyphenols and resistance to pathogens and rots. Phytochemistry, 1996, 42, 1551–1555.
• 16. Naczk M., Amarowicz R., Zadernowski R., Shahidi F., Protein precipitating capacity of condensed tannins of beach pea, canola hulls, evening primrose and faba bean. Food Chem., 2001, 73, 467–471.
• 17. Oomah B.D., Mazza G., Flavonoids and antioxidative activities in buckwheat. J. Agric. Food Chem., 1996, 44, 1746–1750.
• 18. Price M.L, Van Scoyoc S., Butler L.G., A critical evaluation of the vanillic reaction as an assay for tannin in sorghum grain. J. Agric. Food Chem., 1978, 26, 1214–1218.
• 19. Shahidi F., Liyana-Pathirana C.M., Wall D.S., Antioxidant activity of white and black sesame seeds and their hull fractions. Food Chem., 2006, 99, 478–483.
• 20. Steadman K.J., Burgoon M.S., Lewis B.A., Edwardson S.E., Obendorf R.L., Minerals, phytic acid, tannin and rutin in buckwheat seed milling fractions. J. Sci. Food Agric., 2001, 81, 1094– 1100.
• 21. Troszyńska A., Amarowicz R., Wołejszo A., Sensory and chemical approach to astringency of extracts from selected tannin – rich foods. Pol. J. Food Nutr. Sci., 2006, 56, 291–295.
• 22. van Acker S.A.B.E., van den Berg D.J., Tromb M.N.J.L., Griffioen D.H., van Benekom W.P., van der Vijgh W.J.F., Bast A., Structural aspects of antioxidant activity of flavonoids. Free Rad. Biol. Med., 1996, 20, 331–342.
• 23. Watanabe M., Ohshita Y., Tsushida T., Antioxidant compounds from buckwheat (Fagopyrum esculentum Moench) hulls. J. Agric. Food Chem., 1997, 45 1039–1044.
• 24. Watanabe M., Catechins as antioxidants from buckwheat (Fagopyrum esculentum Moench) groats. J Agric. Food Chem., 1998, 46 839–845.
• 25. Wettasinghe M., Shahidi F., Iron (II) chelation activity of extracts of borage and evening primrose meals. Food Res. Int., 2002, 35, 65–71.
• 26. Wijngaard H.H., Arendt E.K., Buckwheat. Cereal Chem., 2006, 83, 391–401.
• 27. Wong S.P., Leong L.P., Koh J.H.W., Antioxidant activities of aqueous extracts of selected plants. Food Chem., 2006, 99, 775–783.