Polyphenolic profile and in vitro biological activity of Serbian orange (skin fermented white) wines.

Orange wines are made from white grapes, but with prolonged skin contact during fermentation. Available data on their composition and potential health benefits are limited, so polyphenolic profile (HPLC analysis) and in vitro biological activities (enzyme inhibition, antioxidant, and anti-inflammatory) of 24 Serbian orange wines were analyzed, including the correlation between determined composition and bioactivities. The wines displayed distinct polyphenolic profiles, enabling partial differentiation based on overall polyphenol content, including dominant components (catechin, gallic and caffeic acids), along with occasional occurrences of anthocyanins. However, no discernible distinctions were noted based on grape varieties, vintage, or producer. All twenty-four orange wines showed a reasonable inhibition of digestive enzymes and lipid peroxidation, twenty-one samples reduced ROS generation in the cell-based assay, but only two suppressed both PGE2 and TXA2 production in U937 cells, implicating possible functional food properties. No significant correlation between polyphenolic profile and determined biological activities was noticed.

Adsorptive stripping voltammetric determination of cefetamet in human urine.

On the basis of previously established mechanism of cefetamet (CEF) reduction, two methods were suggested for CEF determination-differential pulse polarographic and differential pulse adsorptive stripping voltammetric method. Two pH values were chosen, 2.0 and 8.4, where the electrochemical process was defined as one four-electron and two two-electron processes, respectively. The methods were performed in Britton-Robinson (BR) buffer and the corresponding calibration graphs were constructed and statistical parameters were evaluated. Applying the AdSV method at pH 2.0 linearity was achieved from 2 x 10(-8) to 2 x 10(-7) M with limit detection and limit determination of 4 x 10(-9) and 1.4 x 10(-8) M, respectively. At pH 8.4, the linearity was obtained between 6 x 10(-8) and 6 x 10(-7) M, with limit detection and limit determination of 1.5 x 10(-8) and 5 x 10(-8) M, respectively. Since the AdSV method enabled lower concentrations of CEF to be determined, this method was tested for CEF determination in spiked urine samples, and DPP method was used as a comparative one.