Chemical composition, and antioxidant and antimicrobial activities of three hazelnut (Corylus avellana L.) cultivars.

Hazelnut (Corylus avellana L.) is a very popular dry fruit in the world being consumed in different form and presentations. In the present work, three hazelnut cultivars (cv. Daviana, Fertille de Coutard and M. Bollwiller) produced in Portugal, were characterized in respect to their chemical composition, antioxidant potential and antimicrobial activity. The samples were analysed for proximate constituents (moisture, fat, crude protein, ash), nutritional value and fatty acids profile by GC/FID. Antioxidant potential was accessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and b-carotene linoleate model system. Their antimicrobial capacity was also checked against Gram positive (Bacillus cereus, B. subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Results showed that the main constituent of fruits was fat ranging from 56% to 61%, being the nutritional value around 650 kcal per 100 g of fruits. Oleic was the major fatty acid varying between 80.67% in cv. F. Coutard and 82.63% in cv. Daviana, followed by linoleic, palmitic, and stearic acids. Aqueous hazelnut extract presented antioxidant activity in a concentration-dependent way, in general with similar behaviour for all cultivars. Hazelnut extracts revealed a high antimicrobial activity against Gram positive bacteria (MIC 0.1 mg/ mL) showing a good bioactivity of these fruits

Bioactive properties and chemical composition of six walnut (Juglans regia L.) cultivars

The chemical composition, antioxidant potential and antimicrobial activity were studied in six walnuts (Juglans regia L.) cultivars (cv. Franquette, Lara, Marbot, Mayette, Mellanaise and Parisienne) produced in Portugal. Concerning their chemical composition the main constituent of fruits was fat ranging from 78.83% to 82.14%, being the nutritional value around 720 kcal per 100 g of fruits. Linoleic acid was the major fatty acid reaching the maximum value of 60.30% (cv. Lara) followed by oleic, linolenic and palmitic acids. The aqueous extracts of walnut cultivars were investigated by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and b-carotene linoleate model system. All the walnut extracts exhibited antioxidant capacity in a concentration- dependent manner being the lowest EC50 values obtained with extracts of cv. Parisienne. Their antimicrobial capacity was also checked against gram positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans), revealing activity against the different tested microorganisms

The effects of Juglans regia L. (walnut) extract on certain biochemical paramaters and in the prevention of tissue damage in brain, kidney, and liver in CCl4 applied Wistar rats

Yilmaz, Yilmaz, Okkes, Okkes/0000-0002-8276-4498WOS: 000358306700007Objective: The purpose of this study is to demonstrate protective effects of walnut samples on CCl4 induced tissue damage in vivo. Methods: Walnut fruits were extracted and then subjected to vitamin and flavonoid analyses. The extracts obtained were injected intraperitoneally every other day to Wistar male rats given carbon tetrachloride (CCl4) and the animals were decapitated at the end of the study period. The brain, kidney, and liver tissues were removed and lipid peroxidation (LPO) measurements were done in the lipid fraction generated. The fatty acids in the lipid extract were analyzed by gas chromatography after converting them into methyl esters. In addition, the amounts of glutathione, protein, and vitamins were analyzed. Results: Given the results achieved, it was found that the levels of fatty acids increased in the brain and kidney tissues after CCl4 administration (p<0.001). In the groups given walnut extract against CCl4, it was found that the glutathione (GSH) level increased and malondialdehyde (MDA) level reduced in all tissues (p<0.05, p<0.01). Given lipophilic vitamin levels, it was found that a-tocopherol level increased in the brain and liver tissues in the group receiving additional walnut in comparison with the controls (p<0.05), and cholesterol level increased in the tissues, except kidney, in all groups in comparison with the control group (p<0.05, p<0.001). Conclusion: Our data indicates that walnut extract has protective effects against LPO formation in the brain, kidney and liver tissues.Firat University, FUBAP (Firat University Scientific Research Projects Unit)Firat University [1824]This study was supported by Firat University, FUBAP (Firat University Scientific Research Projects Unit) with the project no. 1824