Physico-Chemical and Antioxidant Characteristics in Fruits of Walnut (<i>Juglans regia L.</i>) Genotypes from Inner Anatolia

Abstract

Walnut fruits are used for their nutrition properties for a long time in Anatolia, where seed propagated walnuts are naturally found, as solitary individuals or dense populations. Some relevant physico-chemical and antioxidant characteristics of fruits were determined for fifteen promising walnut (Juglans regia L.) selections (named 'G-1' to 'G-15') propagated from seeds. The well-known Turkish walnut cultivar 'Sebin' was included in the analysis as a standard in order to make comparison with seed propagated genotypes. The average fruit weight and kernel ratios ranged from 7.43 to 12.61 g and 45.10 to 57.83% among the studied genotypes, respectively. The chemical analyses showed that protein, crude oil, ash, carbohydrate and dietary fiber contents of the analyzed walnut genotypes were between 11.09-18.16%, 55.38-65.15%, 1.61-2.08%, 12.01-17.89% and 2.90-4.12%, respectively. Total phenolic content was found between 1,107-1,876 mg GAE/100 g among the genotypes and most of them had higher phenolic content compared with cv. 'Sebin'. The total tocopherols content ranged from 30.0 to 44.4 mg/100 g of the extracted oil. The most common tocopherol in all samples was γ-tocopherol. The results obtained in the hereby study indicated that the seed propagated walnut trees can be very diverse and their nuts have a good potential for valuable sources of phytochemicals.

Some Chemical and Physical Qualities of Cold-Adapted Promising Walnut Genotypes:turkey, Bingol Region

“…Bakkalbasi et al [42] (2013) published a work in which DPPH values for 6 commercial local walnut cultivars in Turkey ranged from 41.91 to 85.15%. In another work, total antioxidant activity determined by TAEC method from 15 genotypes and 'Sebin' cultivar in Turkey was in the range of 93 and 128 µmol Trolox eq./g [43] (Beyhan et al, 2016). When compared to the previously published studies restricted to Turkey, our results were close to the values reported by these works.…”

Fruit physical, chemical and molecular identification of three walnuts (Juglans regia L.) genotypes grown in Egypt

“…The protein results were in agreement with those obtained by Koyuncu and Askin [25] who found that the protein in different walnut genotypes contents varied between 6.30 and 22.0%. Phenol contents were in good agreement with Beyhan et al [6] who found that the phenol content of different pecans was found to be in the range of 50-2,499 mg GAE/100 g %. USDA [26] determined values between 367-1,065 mg GAE/100.The total protein, oil and carbohydrate content of walnuts from Portugal were in the range of 14.38 -18.03%, 68.83 -72.14% and 3.75-6.10%, respectively [27].…”

“…The Juglans division is widely cultivated in the temperate zone [5]. Cooling requirements for walnut trees are as low as 450-1500 hours of temperatures below 10 ° C during winter [6]. Moreover, cultivated walnut varieties are well adapted to the climatic conditions of different production areas [7].…”

Nuts as functional foods: Variation of nutritional and phytochemical profiles and their in vitro bioactive properties

“…In the past years some researchers have focused on horticultural agronomy practice ( Persic et al, 2018 ) or on basic chemical composition, e.g. fat, fatty acid ( Kumawat et al, 2017 , Ros and Mataix, 2006 ) and tocopherols ( Pérez-Fernández et al, 2017 ) or polyphenols in walnuts ( Beyhan, Gozlekci, Gundogdu, & Ercisli, 2016 ), hazelnuts ( Pino Ramos et al, 2019 ), pistachio ( Noguera-Artiaga et al, 2019 ;; Liu et al, 2014 ) or almonds ( Bolling, Dolnikowski, Blumberg, & Chen, 2010 ). Increasingly, research is focused on waste nut products ( Grace et al, 2016 ) and the importance of processing ( Lainas et al, 2016 , Monagas et al, 2009 , Pelvan et al, 2018 , Sonmezdag et al, 2019 , Stuetz et al, 2017 , Trox et al, 2010 ) or nut leaves ( Amaral et al, 2004 , Forino et al, 2016 , Pereira et al, 2007 ), rather than on the nuts themselves.…”