, Volume 14, Issue 2, pp 79–85 | Cite as

Evaluation of the antioxidant activity of foods in human cells

Integrated study of biologically active antioxidants from Camellia sinensis
  • Cecilia Bender
  • Sara Graziano
Original Research


Antioxidant testing of natural products has attracted increasing interest in recent years, mainly due to the fact that antioxidants can neutralise harmful free radicals in vitro, thus suggesting that an antioxidant-rich diet might provide health benefits. Several methods have been developed to examine the antioxidant potential of foods, including the ferric ion reducing antioxidant power (FRAP), peroxyl radical scavenging capacity (PSC), Trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) measurements, among others. However, these chemical assays do not take into consideration key biological parameters that are needed to estimate the potential in vivo effect. In an attempt to better characterize the antioxidant action of natural products, we investigate the effect on intracellular reducing power of aqueous extracts from commercial Camellia sinensis leaves (green, black and white teas), available from an Italian market. The flavonoid contents were determined spectroscopically and the antioxidant activities were assessed using ORAC and PSC assays as well as the cellular antioxidant activity (CAA) method. Our results suggest that although some extracts have a relatively high antioxidant capacity, this rank is dependent on the chemical method used. Moreover, the merely chemical result is sometimes weakly correlated with the cellular defence against oxidative attack. The tested C. sinensis extracts are successfully absorbed at different rates into human cells and among these, green tea had the highest CAA value, followed by white and black teas. Testing the benefits of dietary antioxidants with a cellular model is a great improvement over test tube assays, since it evaluates the antioxidants in a physiological environment and takes into account the complexity of a biological system, thus better reflecting the in vivo situation.


antioxidant activity cellular antioxidant activity ORAC teas bioavailability 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    López-Alarcón C, Denicola A (2013) Evaluating the antioxidant capacity of natural products: a review on chemical and cellular-based assays. Anal Chim Acta 763:1–10CrossRefGoogle Scholar
  2. 2.
    Wolfe KL, Liu RH (2007) Cellular antioxidant activity (CAA) assay for assessing antioxidants, foods and dietary supplements. J Agric Food Chem 55:8896–8907CrossRefGoogle Scholar
  3. 3.
    Wolfe KL, Liu RH (2008) Structure-activity relationships of flavonoids in the cellular antioxidant activity assay. J Agric Food Chem 56:8404–8411CrossRefGoogle Scholar
  4. 4.
    Wolfe IK, Kang X, He X, Dong M, Zhang Q, Liu RH (2008) Cellular antioxidant activity of common fruits. J Agric Food Chem 56:8418–8426CrossRefGoogle Scholar
  5. 5.
    Sharma V, Rao LJM (2009) A thought on biological activities of black tea. Crit Rev Food Sci Nutr 49:379–404CrossRefGoogle Scholar
  6. 6.
    Leung LK, Su Y, Chen R, Zhang Z, Huang Y, Chen ZY (2001) Theaflavins in black tea and catechins in green tea are equally effective antioxidants. J Nutr 131:2248–2251Google Scholar
  7. 7.
    Brown MD (1999) Green tea (Camellia sinensis) extract and its possible role in the prevention of cancer. Altern Rev 4:360–370Google Scholar
  8. 8.
    Chacko SM, Thambi PT, Kuttan R, Nishigaki I (2010) Beneficial effects of green tea: a literature review. Chin Med 5:13CrossRefGoogle Scholar
  9. 9.
    Pekal A, Pyrzynska K (2014) Evaluation of aluminium complexation reaction for flavonoid content assay. Food Anal Methods 7:1776–1782CrossRefGoogle Scholar
  10. 10.
    Cao G, Alessio HM, Cutler RG (1993) Oxygen-radical absorbance capacity assay for antioxidants. Free Radic Biol Med 14:303–311CrossRefGoogle Scholar
  11. 11.
    Prior R, Wu X, Schaich K (2005) Standardized methods for the determination of antioxidant capacity and phenolics in foods and dietary supplements. J Agric Food Chem 53:4290–4302CrossRefGoogle Scholar
  12. 12.
    Bender C, Graziano S, Zimmermann BF, Weidlich HH (2014) Antioxidant potential of acqueous plant extracts assessed by the cellular antioxidant activity assay. Am J Biol Life Sci 2:72–79CrossRefGoogle Scholar
  13. 13.
    Adom KK, Liu RH (2005) Rapid peroxyl radical scavenging capacity (PSC) assay for assessing both hydrophilic and lipophilic antioxidants. J Agric Food Chem 53:6572–6580CrossRefGoogle Scholar
  14. 14.
    Wang Y, Ho CTJ (2009) Polyphenolic chemistry of tea and coffee: a century of progress. Agric Food Chem 57:8109–8114CrossRefGoogle Scholar
  15. 15.
    Liu RH, Finley J (2005) Potential cell culture models for antioxidant research. Agric Food Chem 53:4311–4314CrossRefGoogle Scholar

Copyright information

© CEC editore - Springer-Verlag Italia 2015

Authors and Affiliations

  1. 1.Istituto Kurz Italia S.r.l.ParmaItaly

Personalised recommendations