Characterization of the OMWW. Fresh OMWW was characterized before and after pretreatment.
Contents of the total phenolic compounds in OMWW were expressed as gallic acid equivalents in grams per litre (g GAE/L residue) .
Moreover, the activated bentonite was tested for the adsorption of heavy metal ions from OMWW using a column technique.
Characteristics of OMWW. The OMWW samples were analyzed prior to treatment for different physicochemical properties and the results of the analysis are shown in Table 1.
The influence of adsorbent dose on the adsorption of total phenolic compounds from the OMWW is shown in Figure 5.
In a previous study, we have shown that supplementation of feed with polyphenols from OMWW enhanced the antioxidant mechanisms and decreased oxidative stress-induced damage in broiler chickens .
The results showed that the administration of water supplied with polyphenols from OMWW enhanced the antioxidant mechanisms in chickens.
Interestingly, OMWW-induced increase in catalase activity was both time- and dose-dependent suggesting a major role of this enzyme for OMWW's antioxidant effects.
GSH in erythrocytes was another important antioxidant molecule that was increased after the administration of polyphenols from OMWW through water supply.
The abovementioned enhancement of antioxidant mechanisms after the administration of polyphenols from OMWW through water supply may account for the protection from oxidative stress-induced damage.
Here we demonstrate for the first time that biophenols present in olive leaves and OMWW, such as oleuropein and hydroxytyrosol exhibit leishmanicidal activity in vitro.
In addition to luteolin, which exhibits anti-amastigote activity (Mittra et al., 2000), other bioactive compounds in olive oil and OMWW such as verbascoside, (+)-taxifolin, o-coumaric acid, p-coumaric acid, caffeic acid, ferulic acid, cinnamic acid, and gallic acid also exert in vitro leishmani-cidal activity against axenic L donovani amastigotes (Tasdemir et al., 2006).