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Seventeen phenolic compounds related to the botanical origins of 13 Anzer pollens from Turkey have been analyzed by RP-HPLC. LOD values of standards were found to be between 0.0192 and 0.1313 mg/L with good linearity (r > 0.9977). The mean content of identified total phenolics ranges from 0.5 mg/ 100 g pollen to 2.6 mg/100 g pollen. While a common profile of phenolic compounds comprising p-OH benzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, rutin, trans-cinnamic acid, and cis,trans-abscisic acid was detected in all Anzer pollen, catechin was not determined in any of the pollen samples. Furthermore, antioxidant properties of pollens were determined using total phenolic content, FRAP, CUPRAC and DPPH • (2,2-diphenyl-1picrylhydrazyl) radical-scavenging activity tests. The antioxidant activities showed a marked correlation with total phenolics.

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Chemical and biochemical properties of standard, hybrid, and grafted melons cultivated under the same agricultural conditions in adjacent fields in the Cumra region of Turkey were investigated and compared based on pH, Brix, antioxidant activity, total phenolics, ascorbic acid, individual phenolics, sugar, and organic acid values. Seventeen different phenolic constituents were quantified by reverse phase high-performance liquid chromatography (RP-HPLC). The highest phenolic acid variability and content were detected in the standard melon. Sugar and organic acid compositions of melon cultivars were tested by capillary electrophoresis, and significant differences in types and contents of individual sugars and organic acids were determined among the cultivars. Standard Cinikiz Cumra melons had the highest ascorbic acid, total phenolics, and total sugar contents. The fructose/glucose ratio increased three times in grafted melon as compared with standard melon. While sugar alcohol mannitol existed in the standard and hybrid cultivars, this constituent disappeared in the grafted types. Citric acid found in the standard cultivar was not detected in the hybrid and grafted types. Consequently, it was concluded that the nutritional value of melons changed by the application of hybridization, grafting, or standard (open pollinated) production methods. The standard melon was found to have the highest score in terms of taste, because of its highest sweetness and sourness. It was also found preferable because of its high antioxidant activity, total phenolic and ascorbic acid contents.

This study describes the constituents of phenolic acids and antioxidant activities of chestnut (Castania sativa Mill.) honeys and propolis in Turkey. Antioxidant activity of the chestnut honeys and propolis were examined by three different methods, namely scavenging of free radical 2, 2‐diphenyl‐1‐picrylhydrazyl, FRAP, and cupric reducing antioxidant power. Total phenolic contents were determined by using Folin–Ciocalteu reagent as GA equivalent. The phenolic constituents were also determined by HPLC. The antioxidant activities were compared with standard antioxidants such as catechin, BHT and Trolox. The antioxidant activities of all the samples were found high and related to the sample concentrations. The ethanolic propolis extracts showed the highest antioxidant activity. The major phenolic acids of the chestnut honeys and propolis identified by HPLC with PDA detection were coumaric acid, FA, cinnamic acid, CA and ChA. PRACTICAL APPLICATIONS In this study, some phenolic acid components and antioxidant capacity of chestnut (Castania sativa Mill.) honey and propolis were measured. The comparative findings from antioxidant activities and phenolic acid analyses of honey and propolis samples of chestnut origin provide important criteria for considering their nutritional and nutraceutical potentials. Comparison of our results with literature data also ranks the chestnut honey and propolis as better sources of antioxidants among those from other floral origins.