| Summary: | As a natural potential resource, <i>Tamarix ramosissima</i> has been widely used as barbecue skewers for a good taste and unique flavor. The polyphenolics in the branch bark play a key role in the quality improvement. The purposes of the present work were to explore the polyphenolic composition of <i>T. ramosissima</i> bark extract and assess their potential antioxidant and antimicrobial activities. Hispidulin and cirsimaritin from <i>T. ramosissima</i> bark extract were first identified in the <i>Tamarix</i> genus reported with UPLC-MS analysis. Isorhamnetin (36.91 μg/mg extract), hispidulin (28.79 μg/mg extract) and cirsimaritin (13.35 μg/mg extract) are rich in the bark extract. The extract exhibited promising antioxidant activity with IC<sub>50</sub> values of 117.05 μg/mL for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 151.57 μg/mL for hydroxyl radical scavenging activities, as well as excellent reducing power with an EC<sub>50</sub> of 93.77 μg/mL. The bark extract showed appreciable antibacterial properties against foodborne pathogens. <i>Listeria monocytogenes </i>was the most sensitive microorganism with the lowest minimum inhibitory concentration (MIC) value of 5 mg/mL and minimum bactericidal concentration (MBC) value of 10 mg/mL followed by <i>S. castellani</i> and<i> S. aureus </i>among the tested bacteria. The <i>T. ramosissima</i> bark extract showed significantly stronger inhibitory activity against Gram-positive than Gram-negative bacteria. Nevertheless, this extract failed to show any activity against tested fungi. Overall, these results suggested that <i>T. ramosissima</i> shows potential in improving food quality due to its highly efficacious antioxidant and antibacterial properties.
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