Physicochemical, morphological and functional characteristics of starch isolated from Quercus ilex and Quercus coccifera

The present research work examined and compared the morphological, physicochemical and functional characteristics extracted from two oak varietiesgrowing inTunisia. Among the findings, it was observed that Quercus ilex's starch granules had the the hightest value of lipid and phosphor content. When observed under scanning electron microscopy, both Quercus ilex and Quercus coccifera starch granules exhibited various shapes such as ovoid, spherical, elliptical and irregular, with diameters ranging from 4 to 25 µm. As for the X-ray diffraction patterns, acorn starch from both varieties displayed an A-type pattern. Comparing the properties, Quercus coccifera acorn starch exhibited higher values for the light transmittance values, the solubility, the swelling power and the gelatinization temperatures than Quercus ilex acorn starch. However, the transition enthalpy of Quercus coccifera acorn starch was the lowest among the studied parameters. These results indicate that these properties are significantly (p<0.05) different depending on the oak variety. Thus, the starches of Quercus ilex and Quercus coccifera could play different roles in various industrial applications. Keywords: acorn, functional properties starch,Quercus,physicochemical propertie

Reduction of Oxidizable Pollutants in Waste Water from the Wadi El Bey River Basin Using Magnetic Nanoparticles as Removal Agents

Many of the current strategies for removing pollutants from water are based on nanomaterials and nanotechnology. Lower values of Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) in water results in reduction in the amount of oxidizable pollutants. We present a study on the reduction of COD and BOD5 in water from Wadi El Bey River (Tunisia), using magnetite nanoparticles (MNPs) and magnetic fields. The COD and BOD5 removal reached values higher than 50% after 60 min, with optimum efficiency at pH values of ≈8 and for MNPs concentrations of 1 g/L. The use of a permanent magnetic field (0.33 T) showed an increase of COD and BOD5 removal from 61% to 76% and from 63% to 78%, respectively. This enhancement is discussed in terms of the MNPs coagulation induced by the magnetic field and the adsorption of ionic species onto the MNPs surface due to Fe3O4 affinity