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Peanut sprout (longevity sprout) is one kind of favored food and therapy, due to its crisp taste and unique flavor. The energy, protein, and crude fat content of peanut buds after germination is significantly higher than that of various vegetables. There is a great increase in the content of vitamins, potassium, magnesium minerals, and various amino acids and trace elements required by the human body, especially the content of resveratrol, a polyphenol with important bioactive functions. Among them, resveratrol (chemically known as 3, 4', 5-astragalotriphenol) has the broad-spectrum antibacterial activity as the "plant antitoxin" in recent years. But, there are only a few reports on the effects of peanut bud resveratrol on Salmonella typhimurium. This study was focused on the isolation and purification technique of resveratrol from peanut buds, together with its antibacterial properties. The resins were screened with excellent adsorption and desorption properties for the peanut bud resveratrol compounds, in order to construct the isolation and purification process. The antibacterial efficacy was evaluated to improve the comprehensive utilization of peanut resources. A comparison was made to determine the effects of 16 types of macroporous resins on the separation and purification of arachidonic resveratrol compounds using static adsorption-desorption tests. The LSA-40 was selected as the best adsorption resin for the saturation and plateau in 110 and 90min of static adsorption, respectively. The dynamic adsorption-desorption conditions were optimized as follows. The loading concentration was 120.00 μg/mL, the flow rate was 1.00 mL/min, the pH value was 4.2, and the optimum ratio of loading volume to resin was 8.00 mL/g. The desorption conditions were the 80% ethanol solution, a pH value of 6.6, and a flow rate of 1.00 mL/min. Ultraviolet (UV) spectral analysis showed that the absorption peaks of the purified arachidonic resveratrol and the control were basically the same under the optimized process conditions, where the purity was calculated to be 84.0%. Fourier infrared spectroscopy and ultra-performance liquid chromatography-tandem mass spectrometry were used to identify the components of the purified samples. It was found that the main components of the purified products were resveratrol and the derivatives. The inhibition effect of the purified product on Salmonella typhimurium was evaluated by multiplicative dilution, inhibition growth curve, and cell membrane permeability. The minimum inhibitory concentration of resveratrol-purified product on Salmonella typhimurium was 250 μg/mL. In addition, Salmonella typhimurium treated with resveratrol purification presented a prolonged lag period and a decreased growth rate in the logarithmic phase at the MIC concentration. The cell membrane permeability significantly increased (P < 0.01), according to the growth curve and the protein content of cell contents. The integrity of the cell wall was damaged causing the serious leakage of intracellular proteins, eventually leading to the death of Salmonella typhimurium. This finding can provide some theoretical reference for the comprehensive utilization of peanut resources in natural antibacterial agents. [ABSTRACT FROM AUTHOR]