Search Results (224)

Cutibacterium acnes is linked to the prevalent inflammatory skin disorder known as Acne Vulgaris (AV). Some topical agents exhibit unfavorable side effects like dryness and skin inflammation, and antimicrobial resistance (AMR) poses an increasing risk to effective AV management. This study develops and characterizes stable topical essential oil (EO)-loaded microemulgels with in vitro validated antimicrobial activities against C. acnes ATCC 6919, providing a solid scientific basis for their effectiveness. These microemulgels, with their potential to serve as an alternative to AMR-prone synthetic agents, could revolutionize the field of acne treatment. The MICs of the EOs (citronella, tea tree, and lemongrass) against C. acnes were determined. EO-loaded microemulgels were developed using a blend of microemulsion and carbopol/hyaluronic acid gel in a ratio of 1:1 and characterized, and their stability was observed over three months. The MICs of citronella, tea tree, and lemongrass EOs were 0.08, 0.16, and 0.62% v/v, respectively. The microemulgels were whitish and smooth, with characteristic EO odors. They demonstrated pH values ranging between 4.81 ± 0.20 and 5.00 ± 0.03, good homogeneity, a spreadability of 9.79 ± 0.6 and 12.76 ± 0.8 cm², a viscosity of 29,500 and 31,130 cP, and retained stability at 4, 25, and 40 °C. EO-loaded microemulgels were developed with the potential of C. acnes management. The formulation shows adequate potential for further pharmaceutical development towards translational adoption in acne management. Full article

Carbapenem-resistant Klebsiella pneumoniae (CR-Kp) is eroding therapeutic options for urinary tract infections. We isolated a multidrug-resistant strain from the urine of a chronically bacteriuric patient and confirmed its identity by Vitek-2 and MALDI-TOF MS. Initial disk-diffusion profiling against 48 antibiotics revealed susceptibility to only 5 agents. One month later, repeat testing showed that tetracycline alone remained active, highlighting the strain’s rapidly evolving resistome. Given the scarcity of drug options, we performed an “aromatogram” with seven pure essential oils, propolis, and two commercial phytotherapeutic blends. Biomicin Forte^® produced a 30 mm bactericidal halo, while thyme, tea tree, laurel, and palmarosa oils yielded clear inhibition zones of 11–22 mm. These in vitro data demonstrate that carefully selected plant-derived products can target CR-Kp where conventional antibiotics fail. Integrating aromatogram results into One Health’s stewardship plans may therefore help preserve last-line antibiotics and provide adjunctive options for persistent urinary infections. Full article

Flowering is a key agronomic trait that directly influences the yield of the tea-oil tree (Camellia oleifera). Floral initiation, which precedes flower bud differentiation, represents a critical developmental stage affecting the flowering outcomes. However, the molecular mechanisms underlying floral initiation in C. oleifera remain poorly understood. In this study, buds from five key developmental stages of a 12-year-old C. oleifera cultivar ‘changlin53’ were collected as experimental samples. Scanning electron microscopy was employed to identify the stage of floral initiation. UPLC-MS/MS was used to analyze endogenous gibberellin (GA) concentrations, while transcriptomic analysis was performed to reveal the underlying transcriptional regulatory network. Six GA types were detected during floral initiation and petal development. GA₄ was exclusively detected at the sprouting stage (BII), while GA₃ was present in all samples but was significantly lower in BII and the flower bud primordium formation stage (BIII) than in the other samples. A total of 64 differentially expressed genes were concurrently enriched in flower development, reproductive shoot system development, and shoot system development. Weighted gene co-expression network analysis (WGCNA) identified eight specific modules significantly associated with different developmental stages. The magenta module, containing Unigene0084708 (CoFT) and Unigene0037067 (CoLEAFY), emerged as a key regulatory module driving floral initiation. Additionally, GA20OX1 and GA2OX8 were identified as candidate genes involved in GA-mediated regulation of floral initiation. Based on morphological and transcriptomic analyses, we conclude that floral initiation of C. oleifera is a continuous regulatory process governed by multiple genes, with the FT-LFY module playing a central role in the transition from apical meristem to floral meristem. Full article

Overexploitation has led to a rise in pathogenic bacteria within aquaculture, increasing reliance on antibiotics, and developing microorganism resistance. This situation underscores the need to explore alternatives with a reduced ecological impact. Metabolites derived from essential oils have demonstrated antimicrobial properties that can inhibit or diminish the activity of various microorganisms. In this study, the antimicrobial efficacy of cinnamon (Cinnamomum zeylanicum), tea tree (Melaleuca alternifolia), and thyme (Thymus vulgaris) essential oils against pathogenic bacteria (Aeromonas, Pseudomonas, Shewanella, Comamonas, Vibrio, Acinetobacter, and Empedobacter) isolated from tilapia (Oreochromis spp.) brooded in Hidalgo State, Mexico, were investigated. Diffusion tests were conducted using discs infused with 12 different antibiotics and discs infused with essential oils at concentrations of 15, 10, and 5 μL each. Minimal inhibitory concentration tests were performed using a 96-well microplate format. All bacterial strains exhibited multi-resistance to various antibiotics; however, thyme and cinnamon effectively inhibited the tested bacteria at the lowest concentrations, while tea tree oil was the least effective. The findings suggest the potential incorporation of thyme and cinnamon as an alternative prevention to decrease the use of antibiotic treatment. Full article

Herein, we present scanning electron microscopy imagery of Demodex folliculorum on the eyelashes of a patient with a two-year history of dry, burning, and watery eyes. Demodex mites are part of the normal human skin flora, inhabiting hair follicles and sebaceous glands. However, in some individuals, they may contribute to ocular surface diseases, including blepharitis and dry eye disease. Symptoms often include itching, photophobia, and a foreign body sensation. The pathogenic role of Demodex is not fully understood but may involve microabrasions, gland obstruction, hypersensitivity reactions, and bacterial dysbiosis. The presence of collarettes at the base of eyelashes is a diagnostic hallmark. Although optimal treatment remains debated, options include topical tea tree oil, ivermectin, and a recently FDA-approved drug lotilaner. Our patient responded favorably to a two-month regimen of tea tree oil-based eyelid wipes. This case underscores the clinical relevance of Demodex infestation in chronic ocular discomfort and highlights the importance of diagnostics. Full article

Oil-tea (Camellia oleifera), a typical oilseed tree, produces high-quality edible vegetable oils that contain rich unsaturated fatty acids and diverse lipid-soluble active compounds such as squalene. Although squalene biosynthesis and its molecular regulation have been studied in several plants, the molecular mechanisms underlying squalene biosynthesis in oil-tea seeds remain uncertain. We investigated and determined squalene accumulation with seed development. We conducted comparative transcriptomic analyses using the RNA-seq technique at the early, fast biosynthesis, and late stages of squalene accumulation with oil-tea seed development and identified 13 squalene biosynthesis key enzyme genes (such as CoHMGR_4, CoAACT_2, CoFPS_1, and CoFPS_2) in developing oil-tea seeds. According to whether the expressions of key enzyme genes were associated with squalene accumulation we found that the precursor IPP of squalene biosynthesis obtained via the MVA pathway was dominant with oil-tea seed development. Based on the gene co-expression analyses, we identified multiple transcription factors potentially involved in regulating squalene biosynthesis such as CoMYC2, CoREM39, CobZIP5, CoERF and CoWRKY. Using yeast one-hybrid and dual-luciferase assay experiments we demonstrated that the transcription factor CoMYC2 could activate the expression of a key enzyme gene CoHMGR_4, suggesting that CoMYC2 might be a critical regulator during squalene biosynthesis in oil-tea seed development. This study gives not only insights into understanding the molecular basis of squalene biosynthesis in oil-tea developing seeds but also provides gene resources for developing genetically improved varieties with higher content of squalene in oil-tea. Full article

Background and Objective: Alcoholic liver disease (ALD) is a major health burden caused by chronic alcohol consumption, leading to oxidative stress, inflammation, and fibrosis. Current treatments are limited, highlighting the need for novel therapeutic agents. This study investigated the hepatoprotective effects of ‘Terpinen-4-ol (T4OL)’, a natural monoterpene from tea tree oil, against ethanol-induced liver injury, focusing on its molecular and cellular mechanisms. Materials and Methods: Network pharmacology and molecular docking were employed to predict T4OL’s interaction with ALD-associated targets. Human HepG2 cells were used to validate the in silico findings. Cells were exposed to ethanol (8%) prior to treatment with T4OL or silymarin (SIL), and cytotoxicity was assessed through MTT, crystal violet, and trypan blue assays. Moreover, ELISA and qPCR were conducted to evaluate antioxidant, inflammatory, and fibrotic markers. Results: Network pharmacology analysis suggested that T4OL exerts its hepatoprotective effects by suppressing inflammatory and fibrotic mediators (HIF-1α, TGF-β1, and TNF-α). Docking studies also exhibited a strong binding affinity of T4OL to key ALD targets, with docking scores comparable to SIL. In addition, T4OL (13–1300 µM) dose-dependently protected HepG2 cells from ethanol-induced damage, restoring viability by up to 80% at 650 µM. It significantly elevated antioxidant levels (GSH by 2.5-fold, SOD by 1.8-fold) and suppressed pro-inflammatory and fibrotic markers (IL-6, COL1A1, TIMP-1) by 40–60%. At higher concentrations (650–1300 µM), T4OL outperformed SIL in cytoprotection and anti-fibrotic effects. Conclusions: T4OL mitigates ethanol-induced liver injury by targeting oxidative stress, inflammation, and fibrosis pathways, demonstrating superior efficacy to SIL at optimal doses. Its multi-target action supports its potential as a therapeutic candidate for ALD. Full article

Finding effective alternatives to antibiotics and zinc oxide in livestock feed remains challenging, but phytogenic compounds show promising potential. In the first part of the present study, the in vitro antimicrobial activities of carvacrol, eugenol, garlic oil, star anise oil, and tea tree oil as well as their effects on the biofilm formation of two Escherichia coli field isolates, quorum sensing of Chromobacterium violaceum, and the adhesion of an E. coli field isolate to piglets’ small intestinal mucus were determined. Based on these results, two prototypes were formulated. Phytogenic feed additive (PFA) Core 2, containing carvacrol, eugenol, and star anise oil, showed stronger in vitro antimicrobial activity, inhibition of biofilm formation, and quorum sensing than PFA Core 1, which was mainly composed of garlic oil and tea tree oil. In the second part of the present study, 1000 post-weaning piglets were divided into four groups receiving a control or diets with either PFA Core 1, PFA Core 2, or zinc oxide. Only PFA Core 2 and zinc oxide significantly improved body weight, daily gain, feed efficiency, and fecal scores compared with the control, while PFA Core 1 increased the feed efficiency and fecal scores. The results show that feed additives based on carvacrol and eugenol can improve the growth performance of post-weaning piglets and reduce the incidence of diarrhea, possibly by influencing detrimental bacteria. Furthermore, the present study demonstrates the potential of combinations of in vitro assays to support the development of effective feed additives. Full article

The purpose of this narrative review is to identify and present clinical trials published in the last five years on local delivery agents used as adjuncts to subgingival instrumentation in the non-surgical management of periodontitis. Epidemiological studies have shown that periodontitis is highly prevalent in the general population. Treatment is usually based on mechanical removal of contaminants from the root surface followed by long-term supportive care, resulting in decreased occurrence of tooth loss. Clinical health is not always achieved at all sites, leading to research efforts by researchers to find adjunctive agents to help improve the periodontal condition. This review aims to present the most recent developments in local adjunctive agents for the non-surgical treatment of periodontitis. Therapies used included antimicrobial photodynamic therapy as well as antimicrobial and biomodulating compounds. A search in PubMed was conducted to identify the most recent randomized controlled trials relating to locally delivered adjunctive agents in periodontitis treatment beyond traditional therapies such as chlorhexidine, minocycline and doxycycline. Thirty-one articles published in the last five years were included. The most current evidence from human trials supports that, despite the high variability in experimental protocols, there may be a clinical benefit to antimicrobial photodynamic therapy and gels carrying sodium hypochlorite, melatonin, tea tree oil and Aloe vera. Most recently, advances in nanotechnology, including liposomes, present an avenue forward to potentially increase the effectiveness of current and future local delivery agents in the non-surgical treatment of periodontitis. Full article

Bacterial antimicrobial resistance (AMR) represents a critical public health threat, with increasing resistance compromising the effectiveness of treatments worldwide. Resistance trends, such as fluctuating benzylpenicillin resistance in Staphylococcus aureus, highlight the growing urgency, with projections indicating a rise in resistance to various antibiotics, including complete resistance to gentamicin and tetracycline by 2027. Despite substantial efforts to develop new antibiotics and drug delivery systems, these approaches must undergo rigorous clinical evaluation to ensure their safety and efficacy. In parallel, alternative therapies, such as phytotherapy and apitherapy, have garnered attention for their potential in combating infections. Natural substances like tea tree essential oils and propolis, which exhibit antimicrobial properties, are being increasingly incorporated into novel drug delivery systems. However, much of the research on these materials is not new, with several studies already exploring their effectiveness. To address the escalating AMR crisis, combining advanced therapies with alternative medicine could offer a promising solution. Advanced therapy products could target bacterial genomes and enhance the effectiveness of antibiotics and natural substances. This integrated approach remains underexplored in pre-clinical and clinical trials, presenting future research opportunities to develop more effective strategies in combating AMR. Given the rapid spread of resistant infections, there is an urgent need for innovative antimicrobial agents to overcome emerging resistance mechanisms and improve diagnoses and treatments. Full article

Among free-living amoebae (FLA), Acanthamoeba polyphaga is an important causal agent of Acanthamoeba keratitis (AK), a severe and potentially sight-threatening condition. The present study evaluated the “in vitro” efficiency of Melaleuca alternifolia Cheel (tea tree) (tea tree oil—TTO) and Eucalyptus globulus Labill. (Eucalyptus essential oil—EEO) essential oils against an Acanthamoeba strain isolated from human keratitis. The Minimum Inhibitory Concentration (MIC) of the EOs and the Fractional Inhibitory Concentration (FIC) Index were used to evaluate the decrease in viable cells of Acanthamoeba over time and at different concentrations of EOs, used alone or in association. A relevant amoebicidal effect emerged during the first hours of exposure for both compounds, and TTO was the most effective. The TTO/EEO association clearly indicated a synergistic effect in all tests, and at 2 days post-treatment, no viable A. polyphaga cells were observed at all tested concentrations. In conclusion, the potential therapeutic use of EOs represents a promising therapeutic strategy for the treatment of AK. Full article

This study used an embedding technique to prepare microcapsules with tea tree oil as the core material and a composite of β-cyclodextrin and nano-montmorillonite as the wall material. The prepared microcapsules were analyzed for their morphological characteristics, thermal stability, and major components. Additionally, the microcapsules’ effect on the quality of and active substances contained in refrigerated strawberries was investigated. The results revealed that the optimal preparation conditions for the microcapsules were a montmorillonite addition of 2% (m/v), a core-to-wall ratio of 1:12 (m/m), an encapsulation temperature of 70 °C, and an encapsulation time of 90 min. Under these conditions, the microcapsules achieved an encapsulation efficiency of 77.67%. The capsules emitted a noticeable aroma of tea tree oil, and their primary components, specifically terpinen-4-ol, 1,8-cineole, p-cymene, and terpinolene, were consistent with those of tea tree oil. The release rate of the microcapsules at 60 °C and 90 °C was significantly lower than that of liquid tea tree oil (p < 0.05). A suitable treatment with tea tree oil microcapsules preserved the appearance and quality of the strawberries, inhibited spoilage during refrigeration, reduced weight loss, maintained firmness, delayed declines in soluble solid contents and acidity in later storage stages, and enhanced the activity of the superoxide dismutase, catalase, and ascorbate peroxidase. The prepared microcapsules also suppressed increases in anthocyanins and inhibited the further maturation of the stored strawberries. The optimal preservative effect was achieved with the placement of 5.0 g of tea tree oil microcapsules per 1.2 L of storage space. Full article

This article demonstrates that the quality of laundry soap obtained by hot/cold saponification of two vegetable oils (olive and coconut) and an essential oil (such as Neem, Tea Tree or Thyme) influences the effects obtained after washing textiles: cleansing capacity and antibacterial effect. The results of FTIR, SEM, EDX, thermogravimetry and colorimetry analyses are presented comparatively for hot- and cold-prepared soaps. Saponification, Iodine number and Iodine Number Saponification values are determined for each oil but also for the mixture used in soap-making. Soap quality refers to texture, hardness, foaming capacity, stability, durability, cleansing capacity after washing and antimicrobial capacity. The removal power of greasy dirt (heavy used engine oil) of these laundry soaps is higher than that of some commercial soaps, obtaining dirt visibility <2.6% after washing at 100 °C, soiling addition density SAD < 0.0229 and cleansing capacity between 80.88 and 92.16%. UV-VIS analysis confirms the presence of essential oil in soaps (even after 10 months from manufacture) but also in textiles washed with them. The essential oil imparts strong antimicrobial properties to the laundry soaps (since they do not allow for attachment or multiplication of microorganisms from the environment), which makes them particularly useful in washing and disinfecting textile products used in hospitals. Full article

Background: Dental biofilm-induced gingivitis is a prevalent condition caused by dental plaque accumulation. Chlorhexidine mouthwash is a gold standard for plaque control but is associated with adverse effects such as tooth staining and altered taste. This study aimed to evaluate the clinical and antimicrobial effectiveness of 0.2% tea tree oil mouthwash as a natural alternative to 0.2% chlorhexidine mouthwash. Methods: A comparative study was conducted on 60 participants aged 18–60 years, divided into two groups: Group T (tea tree oil) and Group C (chlorhexidine), each comprising 30 participants. Clinical outcomes assessed included Plaque Index (PI), Gingival Index (GI), Bleeding on Probing (BOP), and microbiological Colony Forming Units (CFUs). Parameters were recorded at baseline, 7 days, and 28 days. Results: Group T exhibited significantly lower PI and BOP scores at 7 and 28 days compared to Group C (p < 0.05). Both groups showed comparable reductions in CFU counts, indicating similar antimicrobial efficacy. Importantly, tea tree oil had fewer adverse effects, with no reports of tooth staining or altered taste, unlike chlorhexidine. Conclusion: Tea tree oil mouthwash demonstrated equivalent or superior clinical outcomes compared to chlorhexidine, with fewer side effects. It is a viable and well-tolerated alternative for managing plaque-induced gingivitis, supporting further research into its long-term use and efficacy. Full article

Squid muscle is delicious and nutritious, but it is highly susceptible to spoilage, severely limiting its market development. This study comprehensively evaluated the effects of gelatin (Gel), essential oil (Ess), and Gel + Ess coating on the quality, flavor, and microorganisms of squid muscle during refrigerated storage (4 °C). The results showed that squid muscle treated with Gel + Ess exhibited higher water-holding capacity and sensory evaluation, but lower pH value, chromaticity, and texture parameters than those treated with sterile water (control) during cold storage. The total volatile basic nitrogen (TVB-N) result demonstrated that the shelf life of squid muscle treated with Gel + Ess coating was extended to 12 days at 4 °C, longer than the control group. The Gel + Ess group had the best inhibitory effect on aldehydes and ketones in refrigerated squid muscle, and it could effectively maintain the flavor quality. In addition, the Gel + Ess coating showed an additive inhibition on the growth of Cockerella and Shiwanella compared to the individual compounds. The Gel + Ess coating is a novel strategy for improving the quality, flavor, and micromolecular metabolites of squid muscle during cold storage. Full article