Nutritional Analysis of Red-Purple and White-Fleshed Pitaya (Hylocereus) Species.

Pitaya is one of the most preferred and produced tropical fruit species recently introduced to the Mediterrranean region in Turkey. Due to its nutritional fruits with high economic value, the popularity of pitaya increases steadily in Turkey as an alternative crop. No detailed nutritional analysis has been undertaken in Turkey so far on fruits of the pitaya species. In this study, we determined and compared some nutritional parameters in fruit flesh of two pitaya (dragon fruit) species (Hylocereus polyrhizus: Siyam and Hylocereus undatus: Vietnam Jaina) grown in the Adana province located in the eastern Mediterranean region in Turkey. The individual sugars, antioxidant activity, total phenolic content, phenolic compounds and volatiles were determined for the first time in Turkey on two pitaya species. The results showed that total phenol content and antioxidant capacity are notably higher in red-fleshed fruits than white-fleshed ones and the predominant phenolic compound in fruits of both species was quercetin. The total sugar content and most of the phenolic compounds in fruits of two pitaya species were similar. A total of 51 volatile compounds were detected by using two Solid Phase Micro Extraction (SPME) fibers, coupled with Gas Chromatography Mass Spectrometry (GC-MS) techniques, and more volatile compounds were presented in the white-fleshed species. Total phenolic content (TPC) of the red-fleshed and white-fleshed pitaya species were 16.66 and 17.11 mg GAE/100 g FW (fresh weight). This study provides a first look at the biochemical comparison of red-fleshed and white-fleshed pitaya species introduced and cultivated in Turkey. The results also showed, for the first time, the biochemical content and the potential health benefit of Hylocereus grown in different agroecological conditions, providing important information for pitaya researchers and application perspective.

Comparison of Polyphenol, Sugar, Organic Acid, Volatile Compounds, and Antioxidant Capacity of Commercially Grown Strawberry Cultivars in Turkey.

The aim of this study was to compare certain important fruit quality parameters such as sugars, organic acids, total phenolic content, antioxidant capacity, and volatile compounds of 10 commercial strawberry cultivars grown in the research and experimental area in Yaltir Agricultural Company located in Adana provinces of Turkey. As for the sugar content of strawberry fruits, fructose was identified as the dominant sugar and the highest value (4.43%) was found in the cultivar "Rubygem". In terms of organic acid, among the examined strawberry cultivars, "Calinda" had the greatest level of citric acid (711.45 mg g-1). Regarding vitamin C content, the highest amount was found in the cultivar "Sabrina" (25.08 mg 100 g-1). Ellagic acid was the main phenolic acid in all examined cultivars (except the "Plared" cultivar), and the highest amount was detected in the "Fortuna" cultivar (3.18 mg 100 g-1). We found that the cultivar FL-127 had the highest total phenolic content (158.37 mg gallic acid equivalent 100 g-1 fresh weight base). Regarding antioxidant capacities, the highest value (88.92%) was found in the cultivar Victory among all the cultivars studied. The detailed analysis of volatile compounds was performed by gas chromatography/mass spectrometry (GC/MS) and 34 compounds were detected. Among them, esters, acids, and alcohols were found to be the major volatile compounds in strawberry fruits. In conclusion, strawberry fruits belong to ten cultivars showed abundant phenolic compounds and at the same time have high antioxidant activity.

Total phenolics, antioxidant activities and fatty acid profiles of six Morchella species.

In present study, total phenolic compound, antioxidant activities and fatty acids of several Morchella species collected from different regions of Turkey were determined. Six species were detected, namely Morchella dunalii (HT562), M. purpurascens group (HT565, HT592, HT662, HT699), M. deliciosa (HT682), M. mediterraneensis (HT698), M. importuna (HT667, HT681) and M. esculenta (HT704). The highest phenolic content was determined in the collection numbered as HT565 (281.96 mg gallic acid equivalent (GAE)/g dry weight), followed by HT699, HT562, HT662, HT592, HT698, HT704, HT681, HT667 and HT682. Antioxidant activities were also evaluated by DPPH and FRAP assays and the maximum (0.51 and 1.04 mmol trolox equivalent (TE)/g dry weight respectively) was observed in HT565. The results for the fatty acids composition showed that assessed Morchella species were rich in nutritionally important unsaturated fatty acids and oleic acid, palmitoleic acid, linoleic acid, α-linolenic acid, palmitic acid, stearic acid and myristic acid were the identified compounds. Linoleic acid was the most common in samples like HT565, HT592, HT704, HT662, HT682 and HT667 and followed by oleic acid except in HT565. In HT681, HT698, HT699 and HT562, oleic acid was dominant and followed by linoleic acid. The ratios of unsaturated fatty acids to saturated fatty acids were calculated as 10.79, 4.78, 6.80, 8.09, 6.67, 4.35, 8.70, 8.64, 7.90 and 7.43 in HT562, HT565, HT592, HT662, HT667, HT681, HT682, HT698, HT699 and HT704 respectively. The sampling locations and species of Morels had influenced the bioactivities and fatty acid compositions of specimens.