title: Phenolic compounds from Halimodendron halodendron (Pall.) voss and their antimicrobial and antioxidant activities.
abstract: Halimodendron halodendron has been used as forage in northwestern China for a long time. Its young leaves and flowers are edible and favored by indigenous people. In this study, eleven phenolic compounds were bioassay-guided and isolated from the aerial parts of H. halodendron for the first time. They were identified by means of physicochemical and spectrometric analysis as quercetin (1), 3,5,7,8,4'-pentahydroxy-3'-methoxy flavone (2), 3-O-methylquercetin (3), 3,3'-di-O-methylquercetin (4), 3,3'-di-O-methylquercetin-7-O-β-d-glucopyranoside (5), isorhamentin-3-O-β-d-rutinoside (6), 8-O-methylretusin (7), 8-O-methylretusin-7-O-β-d-glucopyranoside (8), salicylic acid (9), p-hydroxybenzoic acid (ferulic acid) (10), and 4-hydroxy-3-methoxy cinnamic acid (11). They were sorted as flavonols (1-6), soflavones (7 and 8), and phenolic acids (9-11). Among the compounds, flanools 1-4 revealed a strong antibacterial activity with minimum inhibitory concentration (MIC) values of 50-150 μg/mL, and median inhibitory concentration (IC(50)) values of 26.8-125.1 μg/mL. The two isoflavones (7 and 8) showed moderate inhibitory activity on the test bacteria. Three phenolic acids (9, 10 and 11) showed strong antibacterial activity with IC(50) values of 28.1-149.7 μg/mL. Antifungal activities of the compounds were similar to their antibacterial activities. All these phenolic compounds showed significant antimicrobial activity with a broad spectrum as well as antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and β-carotene-linoleic acid bleaching assays. In general, the flavonol aglycones with relatively low polarity exhibited stronger activities than the glycosides. The results suggest the potential of this plant as a source of functional food ingredients and provide support data for its utilization as forage as well.
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Jihua
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Jingfeng
authors.initials: J
authors.lastname: Lou
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Luo
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Ligang
authors.identifier: 0000-0003-4681-191X
authors.initials: L
authors.lastname: Zhou
authors.affiliation: College of Science, China Agricultural University, Beijing 100193, China.
authors.forename: Mingan
authors.identifier: 0000-0002-3852-0672
authors.initials: M
authors.lastname: Wang
authors.affiliation: College of Plant Science, Tarim University, Alar 843300, Xinjiang, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D007887:Fabaceae / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000378:metabolism / Q000494:pharmacology*; D010936:Plant Extracts / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D010636:Phenols; D010936:Plant Extracts
keywords: Halimondendron halodendron; antimicrobial activity; antioxidant activity; phenolic compounds