Bernardes Lucas Matos Martins, Malta Serena Mares, Santos Ana Carolina Costa, da Silva Rafael Alves, Rodrigues Tamiris Sabrina, da Silva Murillo Néia Thomaz, Bittar Vinicius Prado, Borges Ana Luiza Silva, Justino Allisson Benatti, Nossol Arlene Bispo Dos Santos, Martins Mário Machado, Espíndola Foued Salmen, Mendes-Silva Ana Paula, Ueira-Vieira Carlos
Genetics Laboratory, Institute of Biotechnology, Federal University of Uberlândia, Uberlândia, MG, Brazil.
Department of Psychiatry, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.
Sci Rep. 2025 Mar 27;15(1):10626. doi: 10.1038/s41598-025-95616-4.
Nanotechnology offers promising new avenues for combating drug-resistant pathogens. Given its antioxidant capacity, the water-soluble fraction of Brazilian kefir was hypothesized to serve as an effective reducing agent for the green synthesis of silver nanoparticles (AgNPs). It was further hypothesized that both the entire fraction (WSF) and the < 10 kDa fraction AgNPs would augment the therapeutic effects of kefir, particularly its antimicrobial activity. The successful synthesis was confirmed through the use of UV-Visible spectroscopy and Fourier-transform infrared analyses. WSF-AgNPs demonstrated potent antimicrobial activity, with minimum inhibitory concentrations of 25 µg/mL against A. baumannii (p < 0.0001) and 50 µg/mL against K. pneumoniae (p < 0.0001). Although no toxicity was observed in long-term tests on adult Drosophila melanogaster, AgNPs intake impaired larvae development. Oxidative stress analysis showed mild oxidative imbalance on advanced oxidation protein products (AOPP), sulfhydryl, and reduced glutathione (GSH) contents, with no alterations observed in reactive oxygen species (ROS) quantities, ferric reducing antioxidant power (FRAP), and catalase (CAT) activity. These findings suggest that kefir-derived AgNPs may have potential for combating drug-resistant infections. Future studies should focus on enhancing specificity through compound conjugation and investigating broader applications, including disinfectants, wound healing, and antibiotic development.
纳米技术为对抗耐药病原体提供了有前景的新途径。鉴于其抗氧化能力，推测巴西开菲尔的水溶性部分可作为绿色合成银纳米颗粒（AgNPs）的有效还原剂。进一步推测，整个部分（WSF）和<10 kDa部分的AgNPs都将增强开菲尔的治疗效果，特别是其抗菌活性。通过紫外可见光谱和傅里叶变换红外分析证实了合成成功。WSF-AgNPs表现出强大的抗菌活性，对鲍曼不动杆菌的最低抑菌浓度为25 µg/mL（p<0.0001），对肺炎克雷伯菌的最低抑菌浓度为50 µg/mL（p<0.0001）。虽然在对成年黑腹果蝇的长期测试中未观察到毒性，但摄入AgNPs会损害幼虫发育。氧化应激分析显示，在晚期氧化蛋白产物（AOPP）、巯基和还原型谷胱甘肽（GSH）含量上存在轻度氧化失衡，而活性氧（ROS）数量、铁还原抗氧化能力（FRAP）和过氧化氢酶（CAT）活性未观察到变化。这些发现表明，开菲尔衍生的AgNPs可能具有对抗耐药感染的潜力。未来的研究应专注于通过化合物共轭提高特异性，并研究更广泛的应用，包括消毒剂、伤口愈合和抗生素开发。
