Biochemical characterization and antioxidant activity of walnut kernel (Juglans regia L.) of accessions from Middle and High Atlas in Morocco

Abstract

Biochemical composition and antioxidant activity were determined in kernel nuts for eleven Moroccan walnut (Juglans regia L.) accessions representing its main cropping area. Total oil, carbohydrates, crude protein, energy value, crude fiber and flavonoid have varied significantly between accessions, respectively within the range values of 54.50-65.48%, 8.17-19.25%, 11.5-25.58%, 648.91-713.83 Kcal, 4.17-6.75% and 12.59-62.11mg RE 100 g-1 DM. Besides, mineral composition (mg 100 g-1) of kernel have varied also significantly among accessions and particularly for phosphorus (338.1-675.87), copper (2.08-6.67), zinc (3.39-18.63), iron (1.17-2.64), chromium (0.16-0.20), nickel (1.26-1.45) and boron (0.07-1.49). However, dry matter (96.75-98.56%), moisture (1.44-3.24%), ash (1.67-2.53%), total phenols content (1017-3739 mg GAE 100 g-1 DM), DPPH radical scavenging activity (75.02-85.96%), potassium (210.10-338.93 mg 100 g-1), magnesium (79.15-374.54 mg 100 g-1), sodium (1.17-12.63 mg 100 g-1) and manganese (0.79-1.67 mg 100 g-1) did not show significant variations between accessions. Furthermore, the results showed that Moroccan walnut constitutes an important source of nutrient elements, essentially fat, carbohydrates, protein, phosphorus and zinc, and natural antioxidants, phenolic compounds. Accordingly, consumption of all studied kernels accessions would be beneficial to health. This study showed considerable biochemical variation between the analyzed walnut accessions, which could help to select genotypes with desired traits according to their chemotypes.

Morphometric Traits and iPBS Based Molecular Characterizations of Walnut (Juglans regia L.) Genotypes

“…Data 2). These results are in accordance with previously reported values in several commercial varieties studied by researchers who found walnut kernel as compensating 40-60% of walnut weight, while about 60-70% of the kernel weight was oil and 24% was protein (Muradoğlu et al 2010;Kabiri et al 2019;Verma et al, 2020). Genotypes with a kernel that has 60% or above oil and 12% or above protein are more desirable in walnut breeding programs.…”

Effects of Foliar Applications on Nutrient Concentrations of Kernel, Pomological Properties and Yield of 'Chandler' Walnut Variety at Different Altitudes

“…Mineral composition of kernel was varied significantly among accessions at 650-1996 m altitude in Morocco (Kabiri et al, 2019). In this study, the change depending on the locations was determined in the research conducted at different altitude.…”

“…Further, fruit quality features were improved with plant nutrition applications. In previous studies, the nutrient content of walnut kernel was revealed in different locations (Gülsoy et al, 2016;Batun et al, 2017;Kabiri et al, 2019;Ozyigit et al, 2019). In walnuts, these macromicronutrients are extremely important in terms of fruit development, yield and quality.…”

“…After all, walnuts are an important food in the supply of essential elements to the human body (Simsek, 2016). It was stated that nutrient content may be varied due to effects such as variety, year, ecology, maturity level and the methods of cultivation (Juranovic Cindric et al, 2018;Kabiri et al, 2019). Further, fruit quality features were improved with plant nutrition applications.…”

Nuts-Based Non-Alcoholic Drinks For A Healthy Diet

“…Size characteristic of walnuts collected in different countries (Orman, et al, 2020) Nut Walnut has a high calories level and rich nutrient composition. Walnut kernel contains about 60% of lipids and it is a good source of macronutrients and micronutrients and natural antioxidants like polyphenols, folate, tannins, and walnuts oil are rich in unsaturated fatty acids (Kabiri et al, 2019).…”