Optimization and Kinetic Studies of Ultrasound-Assisted Extraction on Polyphenols from Satsuma Mandarin (Citrus Unshiu Marc.) Leaves

The present article includes the Ultrasound-Assisted Extraction (UAE) of Citrus unsiu Marc. leaves rich in polyphenols. The best possible combinations of solvent, pH of the media, solvent/solid ratio, extraction time, extraction temperature and particle size were obtained for the maximum extraction of Total Phenolic Compounds (TPC) and Total Flavonoid Compounds (TFC) by using One-Factor-at-a-Time (OFAT) approach. The optimum extraction conditions of TPC were as follows: pH 4 in water; solvent/solid ratio of 20:1; extraction time, 54 min; and extraction temperature, 53 degrees C. On the other hand, pH 2 in water, solvent/solid ratio of 42:1, 48 min and 58 degrees C were found to be the optimal conditions for the extraction of TFC. The solvent selection was the most effective parameter for the related system. Additionally, several kinetic models (Film theory, Peleg model, first-order mechanism model and second order mechanism model) were employed to examine the kinetics of UAE

Potential risk assessment of metals in edible fish species for human consumption from the Eastern Aegean Sea

The levels of Hg, Cd, Pb, Cr, Cu and Zn were measured in the tissues of four edible fish species namely: Diplodus annularis, Pagellus erythrinus, Merluccius merluccius and Mullus barbatus, collected from the Turkish Coast of the Aegean Sea. Except for D. annularis, the levels of Cd and Pb in all fish tissues sampled in Aliaga Bay in 2009 were above the tolerable limits according to the Food and Agriculture Organization of the United Nations (FAO). Hg in P. etythrinus and M. barbatus were higher than the maximum permitted limits (FAO), while D. annularis and M. merluccius were lower than the limit for biota in the district of Aliaga. Although the Target Hazard Quotient (THQ) values for Cd, Pb, Cu, Cr, Zn in all fish samples were lower than 1.0, the THQ for Hg levels were higher than 1.0 for most of the samples. According to the THQ values, M. merluccius may be consumed in moderation from Aliaga Bay, while the consumption of M. barbatus and P. erythrinus collected from Aliaga Bay are potentially hazardous to human health due to the Hg concentrations. Fish collected from Izmir Bay can be consumed safely