Identifying Antibacterial Compounds in Black Walnuts (Juglans nigra) Using a Metabolomics Approach
AbstractBlack walnut (Juglans nigra L.) is one of the most economically valuable hardwood species and a high value tree for edible nut production in the United States. Although consumption of black walnut has been linked to multiple health-promoting effects (e.g., antioxidant, antimicrobial, anti-inflammatory), the bioactive compounds have not been systematically characterized. In addition, the associations between different black walnut cultivars and their health-promoting compounds have not been well established. In this study, the kernels of twenty-two black walnut cultivars selected for nut production by the University of Missouri Center for Agroforestry (Columbia, MO, USA) were evaluated for their antibacterial activities using agar-well diffusion assay. Among the selected cultivars, four black walnut cultivars (i.e., Mystry, Surprise, D.34, and A.36) exhibited antibacterial activity against a Gram-positive bacterium (Staphylococcus aureus), whereas other cultivars showed no effect on the inhibition of this bacterium. The antibacterial compounds showing the strongest activity were isolated with bioassay-guided purification and identified using a metabolomics approach. Six antibacterial bioactive compounds responsible for antimicrobial activity were successfully identified. Glansreginin A, azelaic acid, quercetin, and eriodictyol-7-O-glucoside are novel antibacterial compounds identified in the kernels of black walnuts. The metabolomics approach provides a simple and cost-effective tool for bioactive compound identification. View Full-Text
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Ho, K.-V.; Lei, Z.; Sumner, L.W.; Coggeshall, M.V.; Hsieh, H.-Y.; Stewart, G.C.; Lin, C.-H. Identifying Antibacterial Compounds in Black Walnuts (Juglans nigra) Using a Metabolomics Approach. Metabolites 2018, 8, 58.
Ho K-V, Lei Z, Sumner LW, Coggeshall MV, Hsieh H-Y, Stewart GC, Lin C-H. Identifying Antibacterial Compounds in Black Walnuts (Juglans nigra) Using a Metabolomics Approach. Metabolites. 2018; 8(4):58.Chicago/Turabian Style
Ho, Khanh-Van; Lei, Zhentian; Sumner, Lloyd W.; Coggeshall, Mark V.; Hsieh, Hsin-Yeh; Stewart, George C.; Lin, Chung-Ho. 2018. "Identifying Antibacterial Compounds in Black Walnuts (Juglans nigra) Using a Metabolomics Approach." Metabolites 8, no. 4: 58.
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