• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.273-280
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• 2024

In this study, the antibacterial activity and mechanisms of bitter orange extract, a natural antibacterial agent, were investigated, with a focus on its potential application in washing water for controlling Salmonella Typhimurium contamination of salad, a ready-to-eat food. The minimum inhibitory concentration (MIC) of bitter orange extract against S. Typhimurium was determined using the broth dilution method. Subsequently, S. Typhimurium was exposed to various concentrations of bitter orange extract (1/16 MIC-2 MIC) and growth curves were measured. Following treatment with bitter orange extract, we investigated its antibacterial mechanism by measuring intracellular reactive oxygen species (ROS) levels, alterations in membrane potential and integrity, and nucleic acid leakage in S. Typhimurium. Additionally, salads artificially contaminated with S. Typhimurium were treated with different concentrations of bitter orange extract using the dipping method for various durations to assess the reduction effect. The MIC of bitter orange extract against S. Typhimurium was 195.313 mg/L, and bacterial growth was completely inhibited at a concentration of 1 MIC. Furthermore, an increase in bitter orange extract concentration correlated with elevated intracellular ROS levels, membrane potential disruption, membrane damage, and nucleic acid release. Importantly, salads treated with bitter orange extract exhibited a significant reduction in S. Typhimurium counts compared to the control, and prolonged treatment times resulted in further reductions in bacterial counts. Bitter orange extract was more effective than sodium hypochlorite and can be used as a safer salad wash. These findings indicate the potential treatment of salads to prevent foodborne illnesses.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.222-227
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• 2008

Citrus aurantium var. amara L., commonly known as 'bitter orange' or 'sour orange', of the family Rutaceae, has traditionally been used in the treatment of various ailments, and it possesses different types of pharmacological properties. As a part of our on-going studies on the plantsfrom the Iranian flora, the extract of C. aurantium var. amara has been studied for its weight lossproperties using the mice model. While the Sep-Pak fraction, 20% methanol (MeOH) in water, of the hydro-methanolic extract of the peels of C. aurantium var. amara fruits, when injectedintraperitoneal (i.p.) at a dose of 10 mg/kg, significantly decreased the level of weight gain of the mice in comparison with control the group (P < 0.01), the Sep-Pak fraction 80% MeOH in water decreased the initial weight of mice by 0.44% in six weeks. The administration of the total extract(10 and 20 mg/kg, i.p.), and the Sep-Pak fractions, 40% and 60% MeOH in water (10 mg/kg, i.p.)did not show any significant change of weight of the test mice. Of the two active fractions, the80% MeOH in water fraction did not show any noticeable adverse effects on mice, and was therefore analysed by reversed-phase preparative high performance liquid chromatography resulting in the isolation and identification of four major components, two coumarins, meranzin hydrate (1) and bergamottin (2), and two flavonoids, xanthomicrol 5,4'-di-methyl ether (tangeritin, 3) and hymenoxin 5,7-di-methyl ether (nobiletin, 4).