Modeling of polyphenols extraction from pomegranate by-product using rotatable central composite design of experiments

There is a growing request to find an effective method of polyphenols extraction from agro-industry by-product as pomegranate. In this study, response surface methodology (RSM) was used to explore the effect of three factors on ultrasonic assisted extraction (UAE) of total polyphenols (TP), total flavonoids (TF) and condensed tannins (CT) from pomegranate peels. The optimal conditions were determined for each phenolic compound using regression model equations and 3-D plots. The high TP, TF and CT content were obtained with, respectively, liquid/solid ratio of 20.00, 9.77, 9.77, extraction time of 36.38, 41.82, 30.39 min and 36.00, 83.64, 59.26% of ethanol percentage. In fact, liquid/solid ratio of 20, extraction time of 30.94 min and 59.26% of ethanol gives the highest contents of TP, TF and CT simultaneously. The experimental values using optimal conditions agreed with the predicted values. The pomegranate peels extract obtained under optimum conditions have an effective antioxidant activity as determined by ABTS and DPPH assays.     

A gradient of interstitial Niphargus rhenorhodanensis populations in two karst/floodplain transition zones of the French Jura

The Bou-Rouch technique was used to sample two small alluvial plains in two different karst areas. One was mainly supplied by karst water (Verna), the other by both karst and surface water (Pissoir).Physical and chemical characteristics varied with time (seasons) and location of sampling sites at both stations.The distribution of Niphargus rhenorhodanensis populations was influenced by the geographical characteristics of the outlets. Only a small number of individuals was found near the outlet and none in the floodplain when the outlet was located at a base-level (Verna). Individuals were more numerous and their presence constant at all sites and dates when the outlet was located at the overflow level of the massif (Pissoir).     

Contribution à la connaissance des Encyrtidae (Hymenoptera : Chalcidoidea) du Maroc,nouvelles données et comparaison avec la faune d’Afrique du Nord

Au Maroc, la famille des Encyrtidae (Hymenoptera : Chalcidoidea) compte actuellement 46 espèces. Six genres (Acerophagus Smith, 1880, Cerchysiella Girault, 1914, Cheiloneurus Westwood, 1833, Copidosoma Ratzeburg, 1844, Epitetracnemus Girault, 1915, Tineophoctonus Ashmead, 1900) et sept espèces [Cheiloneurus elegans (Dalman, 1820), Copidosoma floridanum (Ashmead, 1900), Epitetracnemus intersectus (Fonscolombe, 1832), Habrolepis pascuorum Mercet, 1921, Metaphycus melanostomatus (Timberlake, 1916), Metaphycus castaneus (Mercet, 1921) et Tineophoctonus armatus (Ashmead, 1888)] sont signalés pour la première fois de ce pays. Les échantillonnages ont été réalisés dans trois stations d’étude au sein de la subéraie de la Maâmora au cours de deux années successives (juin 2012 à avril 2014).