en مقاومت پادزیستی (آنتی بیوتیکی) Antibiotic Resistance مقاله پژوهشی Original Research Article <p style="text-align: justify;"><span style="font-size:16px;"><span style="font-family:Times New Roman;"><b><span style="background:#1f497d"><span style="color:white"><span style="letter-spacing:-.1pt">Background and Aim:</span></span></span></b> <span lang="EN-GB">The ethanolic extract of <i>Teucrium (T.) polium</i> (TPE) was investigated for its phenolic and flavonoid content, antioxidant activity, and potential to modulate antibiotic efficacy against antibiotic-resistant <i>E. coli</i> strains</span>.<br> <b><span style="background:#1f497d"><span style="color:white"><span style="letter-spacing:-.1pt">Materials and Methods:</span></span></span></b> <span lang="EN-GB">Antioxidant properties of TPE were evaluated by chemical-based tests application (total phenolic and flavonoid content, anti-radical activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) test).</span> <span lang="EN-GB">Antibacterial properties of TPE alone and in combination with antibiotics, as well as their effect on proton flux across the bacterial cell membrane were assessed</span>.<span style="color:black"> </span><br> <b><span style="background:#1f497d"><span style="color:white"><span style="letter-spacing:-.1pt">Results:</span></span></span></b> <span lang="EN-GB">TPE demonstrated significant antioxidant activity (IC₅₀ = 73.89 &micro;g/mL) and contained high levels of phenolic (181.7 &plusmn; 2.1 mg GAE/g (</span>gallic acid equivalents<span lang="EN-GB">)) and flavonoid (95.4 &plusmn; 3.1 mg QE/g (</span>quercetin equivalents<span lang="EN-GB">)) compounds. Although TPE exhibited no direct antibacterial effects against the tested microorganisms, it significantly enhanced the efficacy of ampicillin and kanamycin against these strains by decreasing </span>minimum inhibitory concentration<span lang="EN-GB"> (MIC) of ampicillin and kanamycin twice. TPE reduced MIC values of both antibiotics and affected bacterial growth kinetics by reducing growth rates and prolonging lag phases in resistant <i>E. coli</i> strains. Furthermore, TPE influenced membrane-associated properties, specifically reducing proton flux in bacteria, which likely contributed to its modulatory effects. Moreover, in case of the kanamycin-resistant <i>E. coli</i> pARG-25 strain, proton flux was suppressed up to 50% under TPE influence and almost 70% with kanamycin-TPE combination</span>.<br> <b><span style="background:#1f497d"><span style="color:white"><span style="letter-spacing:-.1pt">Conclusion:</span></span></span></b> <span lang="EN-GB">These findings demonstrated <i>T. polium</i> ethanolic extract as an effective antibiotic resistance modulator, offering a potential adjuvant therapy to combat bacterial resistance. Future research should be focused on identifying the specific bioactive compounds responsible for these effects and evaluating their therapeutic applicability.</span></span></span></p> Antibiotic Resistance, Antioxidant, E. coli, Ethanolic Extract, Plant-derived Compound, Proton Flux, Teucrium polium 107 117 http://ijmm.ir/browse.php?a_code=A-10-2747-1&slc_lang=en&sid=1 Silvard Tadevosyan silvard.tadevosyan@ysu.am 100319475328460032495 0009-0005-3818-7274 No Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, Yerevan, Armenia Anush Babayan anush.babayan@ysu.am 100319475328460032496 0009-0008-5300-6170 No Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, Yerevan, Armenia Naira Sahakyan sahakyannaira@ysu.am 100319475328460032497 100319475328460032497 Yes Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, Yerevan, Armenia