Antioxidant capacity of vegetables, spices and dressings relevant to nutrition

Abstract

Vegetables are the most important sources of phenolics in the Mediterranean diet. Phenolics, especially flavonoids, are suggested as being essential bioactive compounds providing health benefits. In this study, twenty-seven vegetables, fifteen aromatic herbs and some spices consumed in Central Italy (the Marches region) were studied to reveal total phenolic, flavonoid and flavanol content as well as their antioxidant capacity measured by the oxygen radical absorbance capacity (ORAC) method. A comparison in terms of antioxidant capacity was made between different salads, as well as between salads to which aromatic herbs had been added. Lemon balm and marjoram at a concentration of 1·5 % w/w increased by 150 % and 200 % respectively the antioxidant capacity of a salad portion. A 200 g portion of a salad enriched with marjoram corresponded to an intake of 200 (SD 10) mg phenolics and 4000 (SD 300) ORAC units (mmol Trolox equivalents). Olive oils and wine or apple vinegars were the salad dressings that provided the highest increase in antioxidant capacity. Among the spices tested, cumin and fresh ginger made the most significant contribution to the antioxidant capacity. The results are useful in surveying the antioxidant parameters of vegetables, herbs and spices produced and consumed in our geographical area as well as in quantifying the daily intake of phenolics and ORAC units. The results can be used in public health campaigns to stimulate the consumption of vegetables able to provide significant health protection in order to prevent chronic diseases.

Polyphenolic content and composition and antioxidative activity of different cocoa liquors

“…In addition, the linear regression analysis showed a high correlation coefficient between the antioxidant activity determined by both methods and total polyphenolic content (R 2 = 0.9868 for DPPH, and 0.9375 for ORAC) (Figure 4). A very high correlation coefficient was also found in many other studies using similar analyses (Adamson et al 1999;Counet et al 2004;Ninfali et al 2005;Sun & Ho 2005;Miller et al 2006). The high correlation between the total polyphenol content and antioxidant capacity allows to suggest that the dominant compounds which contribute to the antioxidant capacity are of polyphenolic structure.…”

“…The oxygen radical absorbance capacity was determined according to the method of Ninfali et al (2005). The final reaction mixture for the assay (3 ml) was prepared as follows: 2.25 ml of 0.04µM fluorescein sodium salt in 0.075M sodium phosphate buffer, pH 7.0, and 0.375 ml of diluted samples or 25µM Trolox as standard.…”

Avaliação da atividade antioxidante dos compostos fenólicos naturalmente presentes em subprodutos do pseudofruto de caju (Anacardium occidentale L.)

“…A presença de compostos fenólicos, tais como flavonóides, ácidos fenólicos, antiocianinas, além dos já conhecidos; vitaminas C, E e carotenóides contribuem para os efeitos benéficos destes alimentos 1, 25 . Somando-se a isto, estudos têm demonstrado que polifenóis naturais possuem efeitos significativos na redução do câncer, e evidências epidemiológicas demonstram correlação inversa entre doenças cardiovasculares e consumo de alimentos fonte de substâncias fenólicas, possivelmente por suas propriedades antioxidantes 12,22 .…”

Influence of postharvest processing and storage on the content of phenolic acids and flavonoids in foods

“…The [175,214], acidification [223], 1-methylcyclopropene (MCP) treatment [41], drying [45,101,213,225], sensory effects [232,233], brewing [131,215], cooking and steaming [33], stress treatment [224], browningblanching and PPO activity [101], and provenience [138].…”