{
    "abstract": "Members of Plectranthus genus such as Plectranthus amboinicus (Lour.) Spreng is a well-known folkloric medicine around the globe in treating several human ailments such as cardiovascular, respiratory, digestive, urinary tract, skin and infective diseases. Its therapeutic value is primarily attributed to its essential oil. Although several properties of Plectranthus amboinicus essential oil have been documented, its mechanism of action and safety has not been completely elucidated.\nTo investigate the anti-infective potential of Plectranthus amboinicus essential oil against Klebsiella pneumoniae using in vitro and in vivo bioassays and identify its mode of action. The study was conducted to scientifically validate the traditional usage of Plectranthus amboinicus oil and propose it as a complementary and alternative medication to combat Klebsiella pneumoniae infections due to emerging antibiotic resistance problem.\nPlectranthus amboinicus essential oil was extracted through steam distillation and was chemically characterized using Gas Chromatography Mass Spectrometry (GC-MS). The antibacterial activity was assessed using microbroth dilution assay, metabolic viability assay and growth curve analysis. The mode of action was elucidated by the proteomics approach using Nano-LC-MS/MS followed by in silico analysis. The results of proteomic analysis were further validated through several in vitro assays. The cytotoxic nature of the essential oil was also confirmed using adenocarcinomic human alveolar basal epithelial (A549) cells. Furthermore, the safety and in vivo anti-infective efficacy of Plectranthus amboinicus essential oil was evaluated through survival assay, CFU assay and histopathological analysis of vital organs using zebrafish as a model organism.\nThe chemical characterization of Plectranthus amboinicus essential oil revealed that it is predominantly composed of thymol. Thymol rich P. amboinicus essential oil demonstrated potent inhibitory effects on Klebsiella pneumoniae growth, achieving a significant reduction at a concentration of 400\u00a0\u03bcg/mL within 4\u00a0h of treatment The nano-LC-MS/MS approach unveiled that the essential oil exerted its impact by disrupting the antioxidant defense system and efflux pump system of the bacterium, resulting in elevated cellular oxidative stress and affect the biosynthesis of biofilm. The same was validated through several in vitro assays. Furthermore, the toxicity of Plectranthus amboinicus essential oil determined using A549\u00a0cells and zebrafish survival assay established a non-toxic concentration of 400\u00a0\u03bcg/mL and 12.5\u00a0\u03bcg/mL respectively. The results of anti-infective potential of the essential oil using Zebrafish as a model organism demonstrated significantly improved survival rates, reduced bacterial load, alleviated visible signs of inflammation and mitigated the adverse effects of infection on various organs, as evidenced by histopathological analysis ensuring its safety for potential therapeutic application.\nThe executed in vitro and in vivo assays established the effectiveness of essential oil in inhibiting bacterial growth by targeting key proteins associated with the bacterial antioxidant defense system and disrupted the integrity of the cell membrane, highlighting its critical role in addressing the challenge posed by antibiotic-resistant Klebsiella pneumoniae.",
    "authors": [
        {
            "affiliation": "Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India.",
            "firstname": "Akshaya Rani",
            "initials": "AR",
            "lastname": "Augustus"
        },
        {
            "affiliation": "Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India.",
            "firstname": "Sudipta",
            "initials": "S",
            "lastname": "Jana"
        },
        {
            "affiliation": "Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India.",
            "firstname": "Malik Basha",
            "initials": "MB",
            "lastname": "Samsudeen"
        },
        {
            "affiliation": "Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India.",
            "firstname": "Hari Prasath",
            "initials": "HP",
            "lastname": "Nagaiah"
        },
        {
            "affiliation": "Department of Biotechnology, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India. Electronic address: sk_pandian@rediffmail.com.",
            "firstname": "Karutha Pandian",
            "initials": "KP",
            "lastname": "Shunmugiah"
        }
    ],
    "conclusions": "The executed in vitro and in vivo assays established the effectiveness of essential oil in inhibiting bacterial growth by targeting key proteins associated with the bacterial antioxidant defense system and disrupted the integrity of the cell membrane, highlighting its critical role in addressing the challenge posed by antibiotic-resistant Klebsiella pneumoniae.",
    "copyrights": "Copyright \u00a9 2024 Elsevier B.V. All rights reserved.",
    "doi": "10.1016/j.jep.2024.118202",
    "journal": "Journal of ethnopharmacology",
    "keywords": [
        "Comparative proteomic profiling",
        "Klebsiella pneumoniae",
        "Plectranthus amboinicus essential oil",
        "Thymol",
        "Toxicity"
    ],
    "methods": null,
    "publication_date": "2024-04-20",
    "pubmed_id": "38641078",
    "results": "The chemical characterization of Plectranthus amboinicus essential oil revealed that it is predominantly composed of thymol. Thymol rich P. amboinicus essential oil demonstrated potent inhibitory effects on Klebsiella pneumoniae growth, achieving a significant reduction at a concentration of 400\u00a0\u03bcg/mL within 4\u00a0h of treatment The nano-LC-MS/MS approach unveiled that the essential oil exerted its impact by disrupting the antioxidant defense system and efflux pump system of the bacterium, resulting in elevated cellular oxidative stress and affect the biosynthesis of biofilm. The same was validated through several in vitro assays. Furthermore, the toxicity of Plectranthus amboinicus essential oil determined using A549\u00a0cells and zebrafish survival assay established a non-toxic concentration of 400\u00a0\u03bcg/mL and 12.5\u00a0\u03bcg/mL respectively. The results of anti-infective potential of the essential oil using Zebrafish as a model organism demonstrated significantly improved survival rates, reduced bacterial load, alleviated visible signs of inflammation and mitigated the adverse effects of infection on various organs, as evidenced by histopathological analysis ensuring its safety for potential therapeutic application.",
    "title": "In vitro and in vivo evaluation of the anti-infective potential of the essential oil extracted from the leaves of Plectranthus amboinicus (lour.) spreng against Klebsiella pneumoniae and elucidation of its mechanism of action through proteomics approach.",
    "xml": "<Element 'PubmedArticle' at 0x788503703ce0>"
}