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There is an increasing interest to bio-components obtained from fruit & vegetable wastes. Anthocyanin is one of the components regained from fruits especially from red ones. Sour cherry is considered as industrial fruit since most of the grown fruit is processed into juice and hence considerable amount of pomace is removed from process. The influences of process parameters on the extraction of phenolic compounds from sour cherry pomace were investigated. Fifty-one percent ethanol concentration, 75°C temperature and 12 mL/g solvent to solid ratio were selected as optimum process parameters. Time effect on the process efficiency was monitored at three different temperatures (25, 50 and 75°C) and total phenolic and total anthocyanin contents were found to reach equilibrium concentrations between 80 and 100 min time intervals. Ethanol concentrations affected differently extraction yield of anthocyanins and non-anthocyanin phenolics. Various individual phenolic compounds present in sour cherry pomace were identified and quantified by HPLC equipped with UV/ Vis PDA. Of the phenolic compounds, cyanidin-3-glucosylrutinoside, neochlorogenic acid and catechin were the most abundant ones found in the pomace. 14.23 ± 0.38 mg/g total phenolic, 0.41±0.02 mg/g total anthocyanin, 0.19 ± 0.02 mg/g cyanidin-3-glucosylrutinoside, 0.22 ± 0.01 mg/g neochlorogenic acid and 0.22±0.02 mg/g catechin contents (dry weight) were determined in the pomace at optimum extraction conditions.

Various triheterocyclic compounds containing benzimidazole, thiophene, and 1,2,4-triazole rings (3-6) were synthesized and screened for their antioxidant activities. The structures of the synthesized compounds (2-6) were judged by 1 H NMR, 13 C NMR, elemental analysis, and LC-MS spectral data. Antioxidant activities of the synthesized compounds (2-6) were determined with CUPric Reducing Antioxidant Capacity (CUPRAC), ABTS (2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)/persulfate, and DPPH (1,1-diphenyl-2-picrylhydrazyl) assays. Most of the compounds showed a significant antioxidant activity and especially, compound 5c showed very good SC 50 value for DPPH method and compound 5h exhibited very high scavenging activity to ABTS method.

Summary The effects of temperature and pretreatment on drying kinetics and thermal degradation of phytonutrients present in pomegranate arils were investigated. The arils were divided into two groups, and half of the samples were pretreated by dipping into 80 °C hot water for 2 min. The drying process was conducted in the vacuum drier at the temperatures of 55, 65 and 75 °C. The fastest drying was completed at 75 °C after pretreatment of the samples. The highest anthocyanin–phenolic compound contents and antioxidant capacity were detected in the arils dried at 55 °C. Seven thin‐layer drying models were used to predict drying curves, and Arrhenius and Eyring–Polanyi models were employed to predict phytonutrient degradation kinetics. Activation energy for drying was 24.26 kJ mol−1 for pretreated samples and 31.54 kJ mol−1 for untreated samples. Effective moisture diffusivities were ranged from 1.43 × 10−9 to 6.03 × 10−9 m2 s−1.