Antioxidant activity compared phenolic content, total

In a study of 92 Finnish edible and nonedible plant materials, a total of 15 berry samples were screened for antioxidant activity (Kahkonen et al., 1999). The activity was compared with the total phenolic content of the samples. Inhibition of methyl linoleate oxidation was used as a measure of antioxidant activity of berry acetone extracts and total phenolics determined by the Folin-Ciocalteau method as GAE/g dry matter of extracts. Berry extracts were high in antioxidant activity among the... 

This study permits to evaluate the amount of phenohcs, flavonoids and their total antioxidant activity linked to six traditional medicinal plants. Antioxidant activity varied greatly among the different plant parts and was highly correlated with the polyphenohc contents. We take an interest in the leaves of A.Leocarpus and in the root barks of T.Macroptera, since they exhibited important antioxidant activities and could be attractive sources of natural antioxidants. Moreover, this comparative study permits to identify and determine by RP-HPLC, five individual phenolic acids and two flavonoids that are mainly at the origin of the antioxidant activity in the studied plant parts. 

SFE is widely used for the extraction of phenolic compounds from grapes or derivatives [48,67,68] (Table 16.4). Furthermore, this technique has been applied in other matrices such as pepper, tomato, and eggplant by Helmja et al., who compared SFE and UAE. This study indicated that SFE provided the poorest results in ctxnparison with the data obtained by UAE [28]. SFE was also compared with traditional techniques such as Soxhlet extraction using ethyl acetate and ethanol as solvents in guava The best results, in terms of extraction yield (total and fraction) and product quality (antioxidant activity and total phenolic content), were obtained when SFE was tqrplied using ethanol as an organic modifier [66]. The effect of pressure and temperature on the SFE was also evaluated, observing that the most appropriate conditions for the extraction of phenolic compounds was an extraction temperature of 60°C and pressure of 102 bar [66]. 

Parsaeimehr A, Sargsyan E, Javidnia K (2010) A comparative study of the antibacterial, antifungal and antioxidant activity and total content of phenolic compounds of cell cultures and wild plants of three endemic species of Ephedra. Molecules 15 1668-1678... 

When antioxidant capacities of the lichens are compared with their phenolic constituents, it could be concluded that antioxidative nature of the lichens might depend on their phenolics. There are many reports which correlate the total phenolic content of lichens and their antioxidant activity. For example, for the methanol extract of Lobaria pulmonaria, there was a strong correlation between antioxidant activity and total phenolic content (Odabasoglu et al. 2004). Kekuda et al. (2012) found highly positive relationship between total phenols and antioxidant activity in methanol extract of a foliose macrolichen Everniastrum cirrhatum. 

Souri E, Amin G, Farsam H et al (2008) Screening of thirteen medicinal plant extracts for antioxidant activity. Iran J Pharm Res 7 149-154 Squadriato GL, Pelor WA (1998) Oxidative chemistry of nitric oxide the roles of superoxide, peroxynitrite, and carbon dioxide. Free Radic Biol Med 25 392-403 Stanly C, Ali DMH, Keng CL et al (2011) Comparative evaluation of antioxidant activity and total phenolic content of selected lichen species from Malaysia. J Pharm Res 4 2824—2827 Stepanenko LS, Krivoshchekova OE, Skirina IF (2002) Functions of phenolic secondary metabolites in lichens from Far East Russia. Symbiosis 32 119-131 Thadhani VM, Choudhary MI, Ali S et al (2011) Antioxidant activity of some lichen metabolites. Nat Prod Res 25 1827-1837... 

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