Evaluation the chemical composition, phenol, flavonoid and antioxidant activity of walnut skin extract (Juglans regia L.)

Authors
1 -MS.c in Food Science and Technology , Department of Food Science and Technology , Faculty of Agriculture , Ferdowsi University of Mashhad , Mashhad , Iran.
2 Professor, Department of Food Science and Technology , Faculty of Agriculture , Ferdowsi University of Mashhad , Mashhad , Iran.
3 Assistant Professor , Department of Nutrition, School of Allied Medicine , Ahvaz Jundishapur University of Medical Sciences , Ahvaz , Iran
Abstract
Today, consumers are more inclined to use healthy and natural additives. Phenolic compounds obtained from natural products are a good option to minimize lipid oxidation. Walnut is one of the most important nuts that is widely cultivated all over the world. Due to the fact that the green skin of the walnut contains about 64% of the wet weight of the walnut fruit, an amount equal to 240 thousand tons of green skin of the walnut is produced from this fruit every year. The walnuts used in this study were purchased in 1400 from the gardens of Saman city located in Chaharmahal and Bakhtiari province. After powdering the dried green peel, extracting with methanol solvent was done by Soxhlet method. In order to identify chemical compounds and functional groups, GC-MS and FTIR tests were performed. Also, the amount of phenol and flavonoids in the extract of walnut skin was measured. Finally, the antioxidant activity of green walnut skin extract was investigated by measuring the reduction of radical capacity with the help of 2-2-diphenyl-1-picrylhydrazyl (DPPH). A total of 89 compounds were identified, representing 99.9% of the total compounds in the extract. The most important identified compounds that had the highest area under the curve included polyphenols, organic compounds and phytosterols. FTIR results indicate the presence of hydroxyl, alkane and aromatic functional groups of lignin. In the present study, the amount of phenolic compounds in walnut peel extract was 96.07±0.22 (mg of gallic acid per gram of dry weight of the sample). Also, the flavonoid compounds of green walnut skin extract were 349 μg/g of quercetin. EC50 values obtained in this study were equal to 0.15. The results showed that the methanolic extract of green walnut skin can be introduced as a substitute for synthetic antioxidants.
Keywords

Subjects


1- Soto-Hernández, M., Tenango, M. P., & García-Mateos, R. (Eds.). (2017). Phenolic compounds: biological activity. BoD–Books on Demand.
2- Tripoli, E., Giammanco, M., Tabacchi, G., Di Majo, D., Giammanco, S., & La Guardia, M. (2005). The phenolic compounds of olive oil: structure, biological activity and beneficial effects on human health. Nutrition research reviews, 18(1), 98-112.
3- Cicerale, S., Lucas, L., & Keast, R. (2010). Biological activities of phenolic compounds present in virgin olive oil. International journal of molecular sciences, 11(2), 458-479.
4- Sabatier, S., & Barthélémy, D. (2001). Bud structure in relation to shoot morphology and position on the vegetative annual shoots of Juglans regia L.(Juglandaceae). Annals of Botany, 87(1), 117-123.
5- Nabavi, S. F., Ebrahimzadeh, M. A., Nabavi, S. M., Mahmoudi, M., & Rad, S. K. (2011). Biological activities of Juglans regia flowers. Revista Brasileira de Farmacognosia, 21, 465-470.
6- Asadi-Shekaari, M., Karimi, A., Shabani, M., Sheibani, V., & Esmaeilpour, K. (2013). Maternal feeding with walnuts (Juglans regia) improves learning and memory in their adult pups. Avicenna journal of phytomedicine, 3(4), 341.
7- Oliveira, I., Sousa, A., Ferreira, I. C., Bento, A., Estevinho, L., & Pereira, J. A. (2008). Total phenols, antioxidant potential and antimicrobial activity of walnut (Juglans regia L.) green husks. Food and chemical toxicology, 46(7), 2326-2331.
8- Fernández-Agulló, A., Pereira, E., Freire, M. S., Valentao, P., Andrade, P. B., González-Álvarez, J., & Pereira, J. A. (2013). Influence of solvent on the antioxidant and antimicrobial properties of walnut (Juglans regia L.) green husk extracts. Industrial crops and products, 42, 126-132.
9- Beiki, T., Najafpour, G. D., & Hosseini, M. (2018). Evaluation of antimicrobial and dyeing properties of walnut (Juglans regia L.) green husk extract for cosmetics. Coloration Technology, 134(1), 71-81.
10- Darvishi, E., Kahrizi, D., & Arkan, E. (2019). Comparison of different properties of zinc oxide nanoparticles synthesized by the green (using Juglans regia L. leaf extract) and chemical methods. Journal of Molecular Liquids, 286, 110831.
11- Liu, J., Meng, M., Li, C., Huang, X., & Di, D. (2008). Simultaneous determination of three diarylheptanoids and an α-tetralone derivative in the green walnut husks (Juglans regia L.) by high-performance liquid chromatography with photodiode array detector. Journal of Chromatography A, 1190(1-2), 80-85.
12- Alizadeh Behbahani, B., Falah, F., Vasiee, A., & Tabatabaee Yazdi, F. (2021). Control of microbial growth and lipid oxidation in beef using a Lepidium perfoliatum seed mucilage edible coating incorporated with chicory essential oil. Food science & nutrition, 9(5), 2458-2467.
13- Falah, F., Vasiee, A., Tabatabaei-Yazdi, F., Moradi, S., & Sabahi, S. (2022). Optimization of γ-aminobutyric acid (GABA) production by Lactobacillus spp. from agro-food waste. Biomass Conversion and Biorefinery, 1-13.
14- Behbahani, B. A., Yazdi, F. T., Vasiee, A., & Mortazavi, S. A. (2018). Oliveria decumbens essential oil: Chemical compositions and antimicrobial activity against the growth of some clinical and standard strains causing infection. Microbial pathogenesis, 114, 449-452.
15- Chang, C. C., Yang, M. H., Wen, H. M., & Chern, J. C. (2002). Estimation of total flavonoid content in propolis by two complementary colorimetric methods. Journal of food and drug analysis, 10(3).
16- Gao, P., Liu, R., Jin, Q., & Wang, X. (2021). Effects of processing methods on the chemical composition and antioxidant capacity of walnut (Juglans regia L.) oil. LWT, 135, 109958.
17- Carvalho, M., Ferreira, P. J., Mendes, V. S., Silva, R., Pereira, J. A., Jerónimo, C., & Silva, B. M. (2010). Human cancer cell antiproliferative and antioxidant activities of Juglans regia L. Food and chemical toxicology, 48(1), 441-447.
18- Keskin, D., Ceyhan, N., & Ugur, A. (2012). Chemical composition and in vitro antimicrobial activity of walnut (Juglans regia) green husks and leaves from West Anatolia. Journal of Pure and Applied Microbiology, 6(2), 583-588.
19- Mandrika, I., Kumar, S., Zandersone, B., Eranezhath, S. S., Petrovska, R., Liduma, I., ... & Tracevska, T. (2021). Antibacterial and anti-inflammatory potential of polyherbal formulation used in chronic wound healing. Evidence-Based Complementary and Alternative Medicine, 2021.
20- Cosmulescu, S. N., Trandafir, I., Achim, G., Mihai, B. O. T. U., Baciu, A., & Gruia, M. (2010). Phenolics of green husk in mature walnut fruits. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 38(1), 53-56.
21- Wang, J., Zhao, J., Nie, S., Xie, M., & Li, S. (2022). MALDI mass spectrometry in food carbohydrates analysis: A review of recent researches. Food Chemistry, 133968.
22- Darvishi, E., Kahrizi, D., & Arkan, E. (2019). Comparison of different properties of zinc oxide nanoparticles synthesized by the green (using Juglans regia L. leaf extract) and chemical methods. Journal of Molecular Liquids, 286, 110831.
23- Haddadi, S. A., Alibakhshi, E., Bahlakeh, G., Ramezanzadeh, B., & Mahdavian, M. (2019). A detailed atomic level computational and electrochemical exploration of the Juglans regia green fruit shell extract as a sustainable and highly efficient green corrosion inhibitor for mild steel in 3.5 wt% NaCl solution. Journal of molecular liquids, 284, 682-699.
24- Akin, M., Nalbantoglu, S., Cuhadar, O., Uzun, D., & Saki, N. (2015). Juglans regia L. extract as green inhibitor for stainless steel and aluminium in acidic media. Research on Chemical Intermediates, 41(2), 899-912.
25- Kamali, M., Khosroyar, S., & Jalilvand, M. R. (2014). Evaluation of phenolic, flavonoids, anthocyanin contents and antioxidant capacities of different extracts of aerial parts of Dracocephalum kotschyi. Journal of North Khorasan University of Medical Sciences, 6(3), 627-634.
26- Ortega, J. T., Parmar, T., Golczak, M., & Jastrzebska, B. (2021). Protective effects of flavonoids in acute models of light-induced retinal degeneration. Molecular Pharmacology, 99(1), 60-77.
27- Kesarkar, S., Bhandage, A., Deshmukh, S., Shevkar, K., & Abhyankar, M. (2009). Flavonoids: an overview. Journal of Pharmacy Research, 2(6), 1148-1154.
28- Wang, H., Liu, F., Yang, L., Zu, Y., Wang, H., Qu, S., & Zhang, Y. (2011). Oxidative stability of fish oil supplemented with carnosic acid compared with synthetic antioxidants during long-term storage. Food Chemistry, 128(1), 93-99.
29- Pereira, J. A., Oliveira, I., Sousa, A., Valentão, P., Andrade, P. B., Ferreira, I. C., ... & Estevinho, L. (2007). Walnut (Juglans regia L.) leaves: Phenolic compounds, antibacterial activity and antioxidant potential of different cultivars. Food and chemical toxicology, 45(11), 2287-2295.
30- Zhang, Y., Yang, L., Zu, Y., Chen, X., Wang, F., & Liu, F. (2010). Oxidative stability of sunflower oil supplemented with carnosic acid compared with synthetic antioxidants during accelerated storage. Food chemistry, 118(3), 656-662.
31- Ma, X., Wei, Q., Zhang, S., Shi, L., & Zhao, Z. (2011). Isolation and bioactivities of organic acids and phenols from walnut shell pyroligneous acid. Journal of Analytical and Applied Pyrolysis, 91(2), 338-343.
32- Ling, B., Hou, L., Li, R., & Wang, S. (2014). Thermal treatment and storage condition effects on walnut paste quality associated with enzyme inactivation. LWT-Food Science and Technology, 59(2), 786-793.