{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T20:53:47Z","timestamp":1790801627488,"version":"4.1.0"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2018,8,28]],"date-time":"2018-08-28T00:00:00Z","timestamp":1535414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Antibiotics are often prescribed in acne treatment; however, Propionibacterium acnes and Staphylococcus epidermidis, the two of the major acne-associated bacteria, developed antibiotic resistance. Essential oils (EOs) present a natural, safe, efficacious and multifunctional alternative treatment. This study aimed to assess the potential anti-acne activity of selected seven EOs commonly used in Mediterranean folk medicine. Antimicrobial activity screening of these oils showed oregano to exhibit the strongest antimicrobial activity with minimum inhibitory concentration (MIC) of 0.34 mg\/mL and minimum bactericidal concentration (MBC) of 0.67 mg\/mL against P. acnes; and MIC of 0.67 mg\/mL and MBC of 1.34 mg\/mL against S. epidermidis. The composition of the most effective EOs (oregano and thyme) was determined using gas chromatography-mass spectrometry (GC-MS). Monoterpenoid phenols predominated oregano and thyme EO with thymol percentile 99 and 72, respectively. Thymol showed MIC 0.70 mg\/mL against both P. acnes and S. epidermidis whereas MBC was 1.40 and 2.80 mg\/mL against P. acnes and S. epidermidis, respectively. Moreover, oregano exhibited the strongest anti-biofilm effect against S. epidermidis with MBIC 1.34 mg\/mL and killing dynamic time of 12 and 8 h against P. acnes and S. epidermidis, respectively. Oregano, the most effective EO, was formulated and tested as a nanoemulsion in an acne animal mouse model. The formulation showed superior healing and antimicrobial effects compared to the reference antibiotic. Collectively, our data suggested that oregano oil nanoemulsion is a potential natural and effective alternative for treating acne and overcoming the emerging antibiotic resistance.<\/jats:p>","DOI":"10.3390\/molecules23092164","type":"journal-article","created":{"date-parts":[[2018,8,28]],"date-time":"2018-08-28T12:19:06Z","timestamp":1535458746000},"page":"2164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":111,"title":["Origanum vulgare L. Essential Oil as a Potential Anti-Acne Topical Nanoemulsion\u2014In Vitro and In Vivo Study"],"prefix":"10.3390","volume":"23","author":[{"given":"Mohammed H.","family":"Taleb","sequence":"first","affiliation":[{"name":"Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"},{"name":"Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Al-Azhar University\u2013Gaza, PO Box 1277, Gaza 79702, Palestine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1290-2197","authenticated-orcid":false,"given":"Nourtan F.","family":"Abdeltawab","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7635-6842","authenticated-orcid":false,"given":"Rehab N.","family":"Shamma","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutics and Industrial pharmacy, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sherein S.","family":"Abdelgayed","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Veterinary Medicine, Cairo University, Cairo 12211, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1644-367X","authenticated-orcid":false,"given":"Sarah S.","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed A.","family":"Farag","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"},{"name":"Department of Chemistry, School of Sciences &amp; Engineering, The American University in Cairo, Cairo 11853, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed A.","family":"Ramadan","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2163","DOI":"10.1016\/S0140-6736(12)61729-2","article-title":"Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990\u20132010: A systematic analysis for the Global Burden of Disease Study 2010","volume":"380","author":"Vos","year":"2012","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"665","DOI":"10.1016\/j.det.2005.05.008","article-title":"Acne, depression, and suicide","volume":"23","author":"Hull","year":"2005","journal-title":"Dermatol. 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