Comparative study of the elimination of copper, cadmium, and methylene blue from water by adsorption on the citrus Sinensis peel and its activated carbon.

The accumulation of heavy metals and dyes in wastewater is a persistent environmental threat with serious hazards consequences affecting all living organisms. Their removal has become a challenging environmental requirement. Adsorption using agricultural waste is one of the cost-effective removal techniques in which the biomass can be valorized. In this study, two adsorbents were prepared and compared in removing copper, cadmium, and methylene blue from water: citrus Sinensis peel (CP) and its activated carbon (AC). Many physical and chemical properties of the prepared adsorbents were investigated using several techniques. Various operational parameters such as initial adsorbate concentration, contact time, pH, adsorbent mass, and temperature were examined. The optimum uptake of Cd, Cu, and MB was obtained after 2 h contact time by using 0.25 g of adsorbent and 400 mg L-1 metal ions or 100 mg L-1 MB initial concentration at pH 5 (for metal ions only) and temperature of 25 °C. Slight superiority for the CP was seen. Furthermore, isothermal models were resolved in all the studied cases. Unlike for MB, the Langmuir model is more applicable for the adsorption of the cations on both adsorbents with maximum adsorption of 80 mg g-1 of Cd(ii) on CP. Finally, the adsorbents achieved good reuse performance, especially for CP which can be used up to 4 times to remove the metal ions, proving that they are low-cost and environmentally friendly materials able to remove inorganic and organic contaminants from water.

Chemical composition, in vitro cytotoxicity and anti-free radical properties of six extracts from Lebanese Trigonella berythea Boiss.

This study represents an original work aimed to recognize the main constitution of Trigonella berythea. The total phenolic content and total flavonoid content of leaves and stems of T. berythea have been estimated. An extraction and purification of phenolic mixture compounds from the leaves and stems of this plant have been performed and their antioxidant potential using the DPPH, H2O2 and chelating of ferrous ions tests has been evaluated. Then, their cytotoxicity on the MCF7 breast cancer cell line by the XTT Cell Viability technique has been studied. Our results demonstrated that leaves of T. berythea had higher total phenolic content and total flavonoid content than stems. On the other hand, the six extract from leaves and stems of this plant demonstrated a high antioxidant potential reaches more than 80%. Also, extracts from leaves of T. berythea had the highest inhibitory effect on MCF7 and U937 cell growth than that of stems. This inhibition was more than 60% for all extracts. These results provide new insight into the health functions of leaves and stems and demonstrate that T. berythea extracts can potentially have health benefits.

Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras.

OBJECTIVE: To determine the chemical composition, total phenolic and total flavonoid contents of the crude extracts from leaves and stems of a Lebanese plant Euphorbia macroclada schyzoceras (E. macroclada), and to evaluate their antioxidant potential using DPPH, H2O2, and chelating of ferrous ions tests. METHODS: Quantification of the total phenolic and total flavonoid contents of the crude extracts from leaves and stems and the antioxidant activities were evaluated using spectrophotometric analyses. The chemical composition has been estimated using different techniques such as IR, LC/MS and NMR. RESULTS: Ethanolic extract from leaves of E. macroclada was better than aqueous extract and showed higher content in total phenolic and total flavonoid than found in the stems. On the other hand, using DPPH and H2O2 tests, this extract from leaves showed higher antioxidant capacity than aqueous extract. However, using the chelating of ferrous ions test, the antioxidant activity of the aqueous extract of both stems and leaves was stronger than that of ethanolic once. The chemical composition of the whole plant showed the presence of some aromatic compounds and fatty acids. CONCLUSIONS: Both ethanolic and water extracts from both parts of this plant are effective and have good antioxidant power. So, this plant can be used in the prevention of a number of diseases related to oxidative stress.