Antioxidants fruits, antioxidant capacity

Scalzo J, Politi A, Pellegrini N, Mezzetti B, and Battino M (2005), Plant genotype affects total antioxidant capacity and phenolic contents in fruit , Nutrition, 21, 207-213. 

Kalt W, Forney CF, Martin A and Prior RL. 1999. Antioxidant capacity, vitamin C, and anthocyanins after fresh storage of small fruits. J Agric Food Chem 47 4638-4644. 

Wang H, Cao G and Prior RL. 1996. Total antioxidant capacity of fruits. J Agric Food Chem 44 701— 705. 

Chun OK, Kim DO, Smith N, Schroeder D, Han JT and Lee CY. 2005. Daily consumption of phenolics and total antioxidant capacity from fruit and vegetables in the American diet. J Sci Food Agric 85 1715-1724. 

Because part of the total content of antioxidant polyphenols and carotenoids is linked to DF as noted previously, an appreciable proportion of the total antioxidant capacity in fruits and vegetables is associated with DF. 

TDAC in the Spanish diet has been estimated at 3,500 pimol Trolox equivalents by the ABTS method. The contribution of each specific food to the TDAC was dependent on both food intake and food antioxidant capacity. The largest contributors to the TDAC were beverages (about 68%) and fruits and vegetables (about 20%). 

An improved method has been developed and validated using fluorescein as the fluorescent probe (Ou and others 2001). This modification provides a direct measure of hydrophilic chain-breaking antioxidant capacity against peroxyl radical. This method has been applied in vegetables of many kinds (Ou and others 2002 Cho and others 2007) and in tropical fruits (Talcott and others 2003 Mahattanatawee and others 2006). 

In 2003, Prior and others described methods for the extraction and analysis of hydrophilic and lipophilic antioxidants, using modifications of the ORAC procedure. These methods provide, for the first time, the ability to obtain a measure of total antioxidant capacity in the protein free plasma, using the same peroxyl radical generator for both lipophilic and hydrophilic antioxidants. This assay was also used to measure the total antioxidant capacity of guava fruit extracts (Thaipong and others 2006). 

Sanchez-Morcno (2002) considered that this assay is an easy and accurate method for determining antioxidant capacity in fruit and vegetable samples. The DPPH assay has been used to determine the antioxidant activity of polyphenols (Sanchez-Moreno and others 1998 Bao and others 2004) flavonols (Jimenez and others 1998 1999 Choi and others 2002) anthocyanin-based natural colorants from berries (Espin and others... 

Cao G, Booth, SL, Sadowski JA and Prior RL. 1998. Increases in human plasma antioxidant capacity after consumption of controlled diets high in fruit and vegetables. Am J Clin Nutr 68(5) 1081—1087. 

Honer K and Cervellati R. 2002b. Measurements of the antioxidant capacity of fruits and vegetables using the BR reaction method. Eur Food Res Technol 215(5) 437—442. 

Jiang H, Ji B, Liang J, Zhou F, Yang Z and Zhang H. 2006. Comparison on the antioxidant capacity of selected fruits and vegetables and their separations. Chem Nat Compd 42(4) 410-414. 

Kevers C, Falkowski M, Tabart J, Defraigne JO, Dommes J and Pincemail J. 2007. Evolution of antioxidant capacity during storage of selected fruits and vegetables. J Agric Food Chem 55(21) 8596-8603. 

Leong LP and Shui G. 2002. An investigation of antioxidant capacity of fruits in Singapore markets. Food Chem 76(1) 69—75. 

Nilsson J, Pillai D, Onning G, Persson C, Nilsson A and Akesson B. 2005. Comparison of the 2,2 -azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) methods to asses the total antioxidant capacity in extracts of fruit and vegetables. Mol Nutr Food Res 49(3) 239-246. 

Ozgen M, Reese RN, Tulio AZ Jr., Scheerens JC and Miller AR. 2006. Modified 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method to measure antioxidant capacity of selected small fruits and comparison to ferric reducing antioxidant power (FRAP) and 2,2 -diphenyl-l-picrylhydrazyl (DPPJf) methods. J Agric Food Chem 54(4) 1151-1157. 

Pellegrini N, Colombi B, Salvatore S, Brenna, OV, Galavema G, Del Rio D, Bianchi M, Bennett RN and Brighenti F. 2007. Evaluation of antioxidant capacity of some fruit and vegetable foods efficiency of extraction of a sequence of solvents. J Sci Food Agric 87(1) 103—111. 

Rababah, TM, Ereifej, KI and Howard, L. 2005. Effect of ascorbic acid and dehydration on concentrations of total phenolics, antioxidant capacity, anthocyanins, and color in fruits. J Agric Food Chem 53(ll) 4444-4447. 

As has been explained in previous chapters, the antioxidant capacity of fruits and vegetables is a function of the amounts and types of phytochemicals that are present in the fresh tissues. However, the individual contribution to the total antioxidant capacity varies widely. Various studies have demonstrated that phenols and flavonoids contribute to a higher extent than ascorbic acid, carotenoids, and others to the antioxidant capacity of fmits and vegetables (Robles-Sanchez and others 2007). It has been observed that a given content of vitamin E in fruits contributes significantly more to the antioxidant capacity than the same content of ascorbic acid. 

Figure 11.1. Effect of storage temperature (0, 5, 10°C) on (I) total anthocyanins (mg/100 g FW), (II) total phenols (mg/100 g FW), and (III) antioxidant capacity measured as ORAC (p.mol TE/g FW) of strawberry fruit (cv. Chandler). Bars show the final values after treatments. Different letters on top of the bars indicate statistical differences among treatments (p < 0.05).

It has been observed that treatment with natural antimicrobial volatiles also affected the antioxidant capacity of fruits (Ayala-Zavala and others 2005). ORAC values of control strawberries changed during storage at 7.5°C (Fig. 11.3, III). However, significant increases in antioxidant capacity values were observed in strawberries treated with methyl jasmonate, methyl jasmonate-ethanol, and ethanol. One explanation for this difference could be associated with differences on total phenol content (Ayala-Zavala and others 2005). 

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