Search Results (26)

The increasing demand for sustainable and safer alternatives in the cosmetic industry has driven the search for multifunctional natural ingredients. Essential oils (EOs), known for their antimicrobial and antioxidant activities, are promising candidates with which to replace synthetic preservatives and antioxidants. This study aimed to evaluate the preservative and antioxidant potential of Lippia origanoides Kunth essential oil, in pure and encapsulated in β-cyclodextrin form, for cosmetic applications. The EO exhibited strong antioxidant activity, with low IC₅₀ values in DPPH and ABTS assays, and demonstrated antimicrobial efficacy, particularly against Escherichia coli and Staphylococcus aureus. Six cosmetic cream formulations were developed and tested for physicochemical and microbiological stability. Formulations with pure EO maintained high antioxidant performance and remained free of bacterial and fungal contamination over time, outperforming the commercial preservatives. In contrast, formulations with encapsulated EO exhibited delayed antioxidant and antimicrobial activity, indicating gradual release. Overall, Lippia origanoides EO proved to be an effective natural alternative to synthetic preservatives and antioxidants. This approach aligns with the current trend of eco-friendly formulations, offering a sustainable solution by incorporating plant-derived bioactives into cosmetic products. Full article

This study investigates the therapeutic potential of Lippia origanoides essential oil (LOEO) in neurological and pharmaceutical applications. The chemical composition of LOEO was analyzed using gas chromatography–mass spectrometry (GC-MS), revealing major constituents, such as carvacrol, thymol, and γ-gurjunene, known for their antioxidant and antimicrobial properties. LOEO demonstrated significant acetylcholinesterase (AChE)-inhibitory activity, particularly in a nanoformulation that enhances bioavailability and stability. Additionally, the major constituent carvacrol, when tested in isolation, also exhibited AChE-inhibitory activity comparable to that of the nanoformulation. Molecular docking analysis indicated strong binding affinities between LOEO compounds and AChE, supporting its therapeutic potential for neurodegenerative diseases like Alzheimer’s. Additionally, in silico pharmacokinetic predictions revealed favorable absorption and blood–brain barrier penetration profiles for key constituents. Despite promising results, this study acknowledges the need for in vivo validation and long-term stability assessments of the nanoformulation. Future research should focus on pharmacodynamic studies and evaluating the oil’s effectiveness in animal models. These findings highlight LOEO as a valuable candidate for developing natural therapies for neurodegenerative diseases. Full article

(1) Background: Could compounds such as monoterpenes and sesquiterpenes present in essential plant oils inhibit bacterial growth as an alternative to help mitigate bacterial resistance? The purpose of this study is evaluating the in vitro antibacterial effect of Lippia organoides EO (LEO) and Thymus vulgaris EO (TEO), individually and in combination with ampicillin, against extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli strains; (2) Methods: Experimental in vitro design with post-test. The EOs were obtained by hydrodistillation and were analyzed by GC. ESBL-producing E. coli strains used were selected from urine cultures and the bla_CTX-M and bla_TEM resistance genes were identified by end point PCR. The disk diffusion method was used for the susceptibility tests. The MICs and MBCs were determined by microdilution test. Finally, the interaction effect was observed by checkerboard assay; (3) Results: A 39.9% decrease in the growth of the strain thymol in TEO and 70.4% in carvacrol in LEO was shown, observing inhibition halos of 32 mm for both EOs. MICs of 632 and 892 μg/mL for LEO and 738 and 940 μg/mL for TEO were determined. Finally, it was observed that, at low doses, there is a synergistic effect between TEO + LEO and EOs + ampicillin; (4) Conclusions: The findings demonstrate that TEO and LEO have an inhibitory effect on ESBL-producing E. coli, suggesting that they are candidates for further studies in the formulation of antibiotics to reduce bacterial resistance to traditional antibiotics. Full article

Due to the challenge of weaning pigs and the need to reduce the use of antimicrobials in animal feed, there is a growing need to look for nutraceutical alternatives to reduce the adverse effects of the post-weaning period. We evaluate the effect of different feed nutraceutical additives on the microbial communities, gut health biomarkers, and productivity of pigs during the post-weaning period. The study involved 240 piglets weaned on the 21st day of age and randomized to six different diets: D1-BD commercial standard feed, D2-AGP: D1 + 150 ppm zinc bacitracin, D3-MD: D1 + 550 ppm maltodextrin, D4-FOS: D1 + 300 ppm fructo-oligosaccharides, D5-EO: D1 + 70 ppm Lippia origanoides essential oil, and D6-SH: D1 + 750 ppm sodium humate. On day 30 post-weaning, zootechnical parameters were evaluated, and jejunal samples were taken to obtain morphometric variables, expression of barrier and enzymatic proteins, and analysis of microbial communities. Animals fed D4-FOS and D5-EO had the lowest feed conversion ratio and higher expression of barrier and enzymatic proteins compared to D1-BD, D2-AGP, and D3-MD. The use of the additives modified the gut microbial communities of the piglets. In conclusion, fructo-oligosaccharides and Lippia origanoides essential oil were the best alternatives to zinc bacitracin as antibiotic growth promoters. Full article

(1) Introduction: Curcumin and Lippia origanoides essential oils have a broad spectrum of biological activities; however, their physicochemical instability, low solubility, and high volatility limit their therapeutic use. Encapsulation in liposomes has been reported as a feasible approach to increase the physicochemical stability of active substances, protect them from interactions with the environment, modulate their release, reduce their volatility, improve their bioactivity, and reduce their toxicity. To date, there are no reports on the co-encapsulation of curcumin and Lippia origanoides essential oils in liposomes. Therefore, the objective of this work is to prepare and physiochemical characterize liposomes loaded with the mixture of these compounds and to evaluate different in vitro biological activities. (2) Methods: Liposomes were produced using the thin-layer method and physiochemical characteristics were calculated. The antimicrobial and cytotoxic activities of both encapsulated and non-encapsulated compounds were evaluated. (3) Results: Empty and loaded nanometric-sized liposomes were obtained that are monodisperse and have a negative zeta potential. They inhibited the growth of Staphylococcus aureus and did not exhibit cytotoxic activity against mammalian cells. (4) Conclusions: Encapsulation in liposomes was demonstrated to be a promising strategy for natural compounds possessing antimicrobial activity. Full article

Staphylococcus aureus infections are prevalent in healthcare and community environments. Methicillin-resistant S. aureus is catalogued as a superbug of high priority among the pathogens. This Gram-positive coccus can form biofilms and produce toxins, leading to persistent infection and antibiotic resistance. Limited effective antibiotics have encouraged the development of innovative strategies, with a particular emphasis on resistance mechanisms and/or virulence factors. Medicinal aromatic plants have emerged as promising alternative sources. This study investigated the antimicrobial, antibiofilm, and antihemolysis properties of three different chemotypes of Lippia origanoides essential oil (EO) against susceptible and drug-resistant S. aureus strains. The chemical composition of the EO was analyzed using GC-MS, revealing high monoterpene concentrations, with carvacrol and thymol as the major components in two of the chemotypes. The third chemotype consisted mainly of the sesquiterpene β-caryophyllene. The MIC values for the two monoterpene chemotypes ranged from 62.5 to 500 µg/mL for all strains, whereas the sesquiterpene chemotype showed activity against seven strains at concentrations of 125–500 µg/mL, which is the first report of its anti-S. aureus activity. The phenolic chemotypes inhibited biofilm formation in seven S. aureus strains, whereas the sesquiterpene chemotype only inhibited biofilm formation in four strains. In addition, phenolic chemotypes displayed antihemolysis activity, with IC₅₀ values ranging from 58.9 ± 3.8 to 128.3 ± 9.2 µg/mL. Our study highlights the importance of L. origanoides EO from the Yucatan Peninsula, which has the potential for the development of anti-S. aureus agents. Full article

Bacterial resistance to antibiotics makes infections increasingly difficult to fight. In this context, the antimicrobial capacity of Lippia origanoides proved to be a relevant alternative. The purpose of this review is to evaluate the antibacterial activity of this essential oil against bacterial strains. This is a narrative review of the literature using the following guiding question: “Does Lippia origanoides essential oil have antimicrobial activity against bacterial strains?”. The descriptors “Lippia origanoides” and “Antimicrobial activity” were applied to the PubMed, Virtual Health Library (VHL) and Embase databases. The inclusion criteria were as follows: contain, whether in the title, abstract or body of the text, a relationship with the antibacterial activity of L. origanoides, and the possibility of accessing the full article. A total of 62 articles were found and 19 studies were chosen. A total of 13 bacteria were analyzed in the tests and the Minimum Inhibitory Concentration (MIC) was as follows: Bacillus cereus (0.62 μL/mL), Bacillus subtilis (1.25 μL/mL), Staphylococcus aureus (1.25–60 μL/mL), Chromobacterium violaceum (0.37 μL/mL), Escherichia coli (0.15–60 μL/mL), Pseudomonas aeruginosa (240 μL/mL), Salmonella cholerasuis (30 μL/mL), Salmonella thypimurium (1.25 μL/mL) and Vibrio parahaemolyticus (0.313 μL/mL). In Bifidobacterium breve and Lactobacillus acidophilus, the Minimum Bactericidal Concentration (MBC) was, respectively, 50 μL/mL and 3.135 μL/mL. In Staphylococcus epidermidis and Salmonella enteritidis, there was only MIC₅₀ (concentration to inhibit 50% of the sample), specifically, 0.37–3.0 μL/mL and 0.37 μL/mL. In total, 27.3% of articles evaluated the antibiofilm capacity of L. origanoides, and the inhibition of biofilm formation reached more than 70% in E. coli and S. aureus. Lippia origanoides essential oil revealed antimicrobial activity in all studies. Ultimately, P. aeruginosa proved to be a strain that still requires further experimentation. Full article

Candida tropicalis is one of the most pathogenic species within the genus. Increased antifungal resistance has been reported, which is in part due to the organism’s ability to form biofilms. In natural products derived from plants, such as essential oils (EOs) or their major components, there is significant potential to develop new antifungals or to both enhance the efficacy and reduce the toxicity of conventional antifungals. This study aimed to evaluate the effect of combining an EO of Lippia origanoides or thymol with fluconazole on an azole-resistant C. tropicalis strain. Synergism was observed in the combination of fluconazole with the EO and with thymol, and minimal inhibitory concentrations for fluconazole decreased at least 32-fold. As a consequence of the synergistic interactions, mitochondrial membrane potential was reduced, and mitochondrial superoxide production increased. Alteration in nuclear morphology, cell surface, and ultrastructure was also observed. In conclusion, the synergistic interaction between L. origanoides EO or thymol with fluconazole reverted the azole-resistant C. tropicalis phenotype. These findings suggest that L. origanoides EO or thymol alone, or in combination with fluconazole, have the potential for development as antifungal therapies for this yeast, including resistant strains. Full article

Nontyphoidal Salmonella species are one of the main bacterial causes of foodborne diseases, causing a public health problem. In addition, the ability to form biofilms, multiresistance to traditional drugs, and the absence of effective therapies against these microorganisms are some of the principal reasons for the increase in bacterial diseases. In this study, the anti-biofilm activity of twenty essential oils (EOs) on Salmonella enterica serovar Enteritidis ATCC 13076 was evaluated, as well as the metabolic changes caused by Lippia origanoides thymol chemotype EO (LOT-II) on planktonic and sessile cells. The anti-biofilm effect was evaluated by the crystal violet staining method, and cell viability was evaluated through the XTT method. The effect of EOs was observed by scanning electron microscopy (SEM) analysis. Untargeted metabolomics analyses were conducted to determine the effect of LOT-II EO on the cellular metabolome. LOT-II EO inhibited S. Enteritidis biofilm formation by more than 60%, without decreasing metabolic activity. Metabolic profile analysis identified changes in the modulation of metabolites in planktonic and sessile cells after LOT-II EO treatment. These changes showed alterations in different metabolic pathways, mainly in central carbon metabolism and nucleotide and amino acid metabolism. Finally, the possible mechanism of action of L. origanoides EO is proposed based on a metabolomics approach. Further studies are required to advance at the molecular level on the cellular targets affected by EOs, which are promising natural products for developing new therapeutic agents against Salmonella sp. strains. Full article

Microbial infections resistant to conventional antibiotics constitute one of the most important causes of mortality in the world. In some bacterial species, such as Escherichia coli and Staphylococcus aureus pathogens, biofilm formation can favor their antimicrobial resistance. These biofilm-forming bacteria produce a compact and protective matrix, allowing their adherence and colonization to different surfaces, and contributing to resistance, recurrence, and chronicity of the infections. Therefore, different therapeutic alternatives have been investigated to interrupt both cellular communication routes and biofilm formation. Among these, essential oils (EO) from Lippia origanoides thymol-carvacrol II chemotype (LOTC II) plants have demonstrated biological activity against different biofilm-forming pathogenic bacteria. In this work, we determined the effect of LOTC II EO on the expression of genes associated with quorum sensing (QS) communication, biofilm formation, and virulence of E. coli ATCC 25922 and S. aureus ATCC 29213. This EO was found to have high efficacy against biofilm formation, decreasing—by negative regulation—the expression of genes involved in motility (fimH), adherence and cellular aggregation (csgD), and exopolysaccharide production (pgaC) in E. coli. In addition, this effect was also determined in S. aureus where the L. origanoides EO diminished the expression of genes involved in QS communication (agrA), production of exopolysaccharides by PIA/PNG (icaA), synthesis of alpha hemolysin (hla), transcriptional regulators of the production of extracellular toxins (RNA III), QS and biofilm formation transcriptional regulators (sarA) and global regulators of biofilm formation (rbf and aur). Positive regulation was observed on the expression of genes encoding inhibitors of biofilm formation (e.g., sdiA and ariR). These findings suggest that LOTCII EO can affect biological pathways associated with QS communication, biofilm formation, and virulence of E. coli and S. aureus at subinhibitory concentrations and could be a promising candidate as a natural antibacterial alternative to conventional antibiotics. Full article

Bacteria can communicate through quorum sensing, allowing them to develop different survival or virulence traits that lead to increased bacterial resistance against conventional antibiotic therapy. Here, fifteen essential oils (EOs) were investigated for their antimicrobial and anti-quorum-sensing activities using Chromobacterium violaceum CV026 as a model. All EOs were isolated from plant material via hydrodistillation and analyzed using GC/MS. In vitro antimicrobial activity was determined using the microdilution technique. Subinhibitory concentrations were used to determine anti-quorum-sensing activity by inhibition of violacein production. Finally, a possible mechanism of action for most bioactive EOs was determined using a metabolomic approach. Among the EOs evaluated, the EO from Lippia origanoides exhibited antimicrobial and anti-quorum activities at 0.37 and 0.15 mg/mL, respectively. Based on the experimental results, the antibiofilm activity of EO can be attributed to the blockage of tryptophan metabolism in the metabolic pathway of violacein synthesis. The metabolomic analyses made it possible to see effects mainly at the levels of tryptophan metabolism, nucleotide biosynthesis, arginine metabolism and vitamin biosynthesis. This allows us to highlight the EO of L. origanoides as a promising candidate for further studies in the design of antimicrobial compounds against bacterial resistance. Full article

Most Candida species are opportunistic pathogens with the ability to form biofilms, which increases their resistance to antifungal drug therapies and the host immune response. Essential oils (EOs) are an alternative for developing new antimicrobial drugs, due to their broad effect on cellular viability, cell communication, and metabolism. In this work, we evaluated the antifungal and antibiofilm potential of fifty EOs on C. albicans ATCC 10231, C. parapsilosis ATCC 22019, and Candida auris CDC B11903. The EOs’ antifungal activity was measured by means of a broth microdilution technique to determine the minimum inhibitory and fungicidal concentrations (MICs/MFCs) against the different Candida spp. strains. The effects on biofilm formation were determined by a crystal violet assay using 96-well round-bottom microplates incubated for 48 h at 35 °C. The EOs from Lippia alba (Verbenaceae family) carvone-limonene chemotype and L. origanoides exhibited the highest antifungal activity against C. auris. The L. origanoides EOs also presented antifungal and antibiofilm activity against all three Candida spp., thus representing a promising alternative for developing new antifungal products focused on yeast infections, especially those related to biofilm formation, virulence factors, and antimicrobial resistance. Full article

Combustion is the most commonly used technology to produce energy from biomass; nevertheless, there are still thermal efficiency problems in current biomass combustion furnaces and a lack of knowledge about the properties of residual biomasses that could be used as fuels. Aiming to contribute to knowledge of the potential of residual biomass for energy generation, this work reports on the implementation of a 2D computational model to study the combustion performance of several solid biomass fuels, and its application in the analysis of Lippia origanoides bagasse combustion. The model uses an Eulerian–Lagrangian approach; in the continuous phase, governing equations are solved, and in the dispersed phase, particles are tracked and the mass, momentum, species and energy transfer between the phases are calculated. The model was validated against experimental data from a combustor fueled by three biomasses: wood pellets, olive stone and almond shell. The results show deviations of less than 13%, with few exceptions, which indicates a good degree of agreement with experimental measurements compared with those reported by other studies on the subject. Furthermore, it was found that the stems of Lippia origanoides bagasse show similar performance to that of other biomass used as solid fuel, while the leaves present lower performance. Full article

The study aimed to determine the enhanced effects of essential oils (EOs) and plant-derived molecules (PDMs) as penetration enhancers (PEs) for transdermal drug delivery (TDD) of caffeine. A 1% w/w solution of eight EOs and seven PDMs was included in the 1% caffeine carbopol hydrogel. Franz diffusion cell experiments were performed using mice with full-thickness skin. At various times over 24 h, 300 μL of the receptor were withdrawn and replaced with fresh medium. Caffeine was analyzed spectrophotometrically at 272 nm. The skin irritation effects of the hydrogels applied once a day for 21 days were investigated in mice. The steady-state flux (J_SS) of the caffeine hydrogel was 30 ± 19.6 µg cm⁻² h⁻¹. An increase in caffeine J_SS was induced by Lippia origanoides > Turnera diffusa > eugenol > carvacrol > limonene, with values of 150 ± 14.1, 130 ± 47.6, 101 ± 21.7, 90 ± 18.4, and 86 ± 21.0 µg cm⁻² h⁻¹, respectively. The Kp of caffeine was 2.8 ± 0.26 cm h⁻¹, almost 2–4 times lower than that induced by Lippia origanoides > Turnera diffusa > limonene > eugenol > carvacrol, with Kp values of 11 ± 1.7, 8.8 ± 4.2, 6.8 ± 1.7, 6.3 ± 1.2, and 5.15 ± 1.0 cm h⁻¹, respectively. No irritating effects were observed. Lippia origanoides, Turnera diffusa, eugenol, carvacrol, and limonene improved caffeine’s skin permeation. These compounds may be as effective as the PE in TDD systems. Full article

The essential oils (EOs) from bioactive species can provide an alternative tool for the management of stored grain insects that is less environmentally damaging than synthetic chemicals. The aim of this study was to assess the repellent action and toxicity of EOs obtained from phellandrene-rich Lippia origanoides, carvone-rich Lippia alba, citral-rich L. alba, and Pogostemon cablin aerial parts on adults of Ulomoides dermestoides. These EOs were isolated by hydrodistillation and characterized by gas chromatography coupled to mass spectrometry (GC-MS). The repellency assay was carried out using the area preference method, and the toxicity evaluated utilizing a filter paper contact test. The major components (>10%) of the studied EOs were sabinene (16.9%), trans-β-caryophyllene (18.6%) and α-humulene (10.1%) for phellandrene-rich L. origanoides EO; limonene (40.1%) and carvone (37.7%) for carvone-rich L. alba EO; geranial (24.5%), geraniol (19.0%), and neral (11.9%) for citral-rich L. alba EO; and α-guaiene (13.3%), α-bulnesene (15.7%), and patchoulol (35.3%) for P. cablin EO. All EOs displayed 100% repellency at a concentration of 16 μL/mL, with lower toxicity than that elicited by the commercial repellent DEET. EO concentrations up to 8 µL/mL did not induce any mortality on the beetle. These findings show that the EOs provide active and safe molecules for natural repellent formulations to prevent and control insect infestations of stored products. Full article