Search Results (46)

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

There is still a need to develop scenarios and models aimed at substituting fuelwood and reducing the use of fossil fuels such as liquefied petroleum gas (LPG), on which low-income rural households in the Global South often depend. The use of these fuels for cooking and heating in domestic and productive activities poses significant health and environmental risks. This study validated, in three different phases, the sustainability of a model for the production and use of biogas from the treatment of swine-rearing wastewater (WWs) on a community farm: (i) A Multi-Criteria Analysis (MCA), incorporating environmental, social/health, technical, and economic criteria, identified the main weighted criterion to C8 (use of small-scale technologies and low-cost access), with a score of 0.44 points, as well as the Tubular biodigester (Tb) as the most suitable option for the study area, scoring 8.1 points. (ii) Monitoring of the Tb over 90 days showed an average biogas production of 2.6 m³ d⁻¹, with average correlation 0.21 m³ Biogas kg Biomass⁻¹. Using the experimental biogas production rate (k = 0.0512 d⁻¹), the process was simulated with the BgMod model, achieving an average deviation of only 10.4% during the final production phase. (iii) The quantification of benefits demonstrated significant reductions in firewood use: in Scenario S1 (kitchen energy needs), biogas replaced 83.1% of firewood, while in Scenario S2 (citronella essential oil production), the substitution rate was 24.1%. In both cases, the avoided emissions amounted to 0.52 tons of CO_2eq per month. Finally, this study proposes a synthesised, community-based rural biogas framework designed for replication in regions with similar socio-environmental, technical, and economic conditions. Full article

Citrus canker, caused by Xanthomonas citri subsp. citri, is a devastating disease that affects citrus production and trade worldwide. Traditional control methods, based on copper compounds, are effective but pose environmental and health risks due to their toxicity and potential for bioaccumulation. This study evaluates the synergistic potential of essential oils (EOs) and rhamnolipids as sustainable alternatives for disease management. Four EOS (citronella, palmarosa, geranium, and clove) were tested for their antibacterial activity. Citronella EO showed a 90% inhibitory concentration (IC 90) of 0.15% (v/v) and a minimum bactericidal concentration of 0.25% (v/v), while the other EOs showed IC 90 and bactericidal activity at 0.06% (v/v). Rhamnolipids (RHLs), biosurfactants produced by Pseudomonas aeruginosa, inhibited X. citri at a concentration of 0.3% (v/v). The combination of citronella EO and RHLs showed a synergistic effect, reducing the inhibitory concentration of citronella by 50% and that of RHLs by more than 90%. In addition, the combined formulation permeabilized more than 80% of bacterial membranes and reduced biofilm formation. In contrast, other oils tested in combination with rhamnolipid showed independent effects. These results indicate that EOs and rhamnolipids represent an environmentally safe strategy for the control of X. citri subsp. citri that overcomes the limitations of conventional methods while reducing environmental and health impacts. Full article

This study examines the phytochemical composition, antioxidant, antifungal, and insecticidal properties of Origanum syriacum (Syrian oregano plant) and Cymbopogon wimterianus (Java citronella plant) extracts. Their potential applications in food preservation and pest control are explored based on their bioactive properties. The phytochemical screening indicated a rich presence of secondary metabolites in the extract. The hydrodistillation of plant leaves resulted in an extraction yield of 4.3% Syrian oregano essential oil. The major component of the essential oil was carvacrol (79.30%). The Syrian oregano ethanolic extract contained 110.674 ± 1.842 mg GAE/g total phenols and 52.57 ± 0.086 mg RE/g total flavonoids, and exhibited a high antioxidant activity with a half-maximal inhibitory concentration (IC₅₀) equal to 168.28 μg/mL. Flatbread was prepared with additions of Syrian oregano and Java citronella powders, followed by analysis of moisture content, visual appearance, and sensory characteristics. The results showed that the powders of Syrian oregano and Java citronella have promising food preservative effects. These findings were supported by a significant decrease in fungal growth in several samples and a shelf life extension of one day. The inclusion of a 2% mixture of Syrian oregano and Java citronella powder in the flatbread resulted in the sample receiving the highest overall acceptability mark from consumers, while also extending its shelf life. To assess the insecticidal activity, weevils (Sitophilus granarius L.) were exposed to Syrian oregano and Java citronella essential oils. The insecticidal activity was at its peak when Syrian oregano and Java citronella essential oils were combined resulting in 7% lethal dose (LD₅₀) towards grain weevils. Future research should focus on optimizing extraction methods, evaluating long-term storage effects, and assessing the broader applicability of these extracts in various food products and agricultural settings. Full article

The present study aimed to analyze the antifungal, antioxidant, and irritant potential of citronella oil, both isolated and combined with caffeic acid phenethyl ester (CAPE), for topical oral candidiasis. The antioxidant potential was evaluated using two methods, the DPPH test and the reducing power test (FRAP), while the irritant potential of the solutions was assessed through the hen’s egg chorioallantoic membrane test (HET-CAM). The DPPH test (IC50) values for the CITRO III + CAPE III combination were 32 ± 9 mg/mL, and for isolated CAPE, 13 ± 3 mg/mL. The results from the FRAP method revealed a low iron-reducing power for the combination of 1.25 mg/mL of citronella and 0.0775 mg/mL of CAPE (CITRO III + CAPE III), showing no significant difference compared to the isolated solution of 0.15 mg/mL of CAPE. The antibacterial activity of CAPE and isolated citronella in vitro against microorganisms was evaluated using two methods: microdilution and biofilm assay. The results showed that the MIC and MFC values were 0.5 mg/mL for citronella at both tested times (24 h and 48 h). For CAPE, the MFC values were 0.031 mg/mL. For the biofilm assay, the isolated compounds and combinations at 1 min and 6 h showed significantly different results from the controls (p < 0.05). Furthermore, the HET-CAM results demonstrated the absence of irritability. Based on these premises, the antifungal and antioxidant actions, and absence of irritability were proven. Moreover, this work presents a natural antifungal of interest to the pharmaceutical industry. Full article

This study aims to evaluate the effect of these essential oils and their blends on the fermentative profile, losses by gases and effluents, nutritional value, microbial count, and aerobic stability of sorghum silage. A completely randomized design was used with eight treatments and four repetitions. The evaluated treatments were the following: control (CON), without any essential oil; rosemary (Ros); tea tree (TT); citronella (Cit); Ros + TT (50% + 50%); Ros + Cit (50% + 50%); TT + Cit (50% + 50%); and Ros + TT + Cit (33% + 33% + 33%). A 1000 mg/kg dose of ensiled mass (as-fed basis) was used for each of the treatments. The addition of essential oils and their blends had a significant impact (p < 0.05) on the chemical composition of sorghum silage. Crude protein content increased (p < 0.001) with the use of essential oils and their blends. The Ros affected (p < 0.05) the fibrous fraction of sorghum silage. Neutral detergent fiber in vitro degradability was reduced (p = 0.003) when we used the blend TT + Cit compared to Ros and TT. We observed that only Ros did not reduce acetic acid concentration (p = 0.031) compared to the CON. The essential oils and their blends did not affect losses (p > 0.05). Lactic acid bacteria population increased (p = 0.039) when using the blend Ros + TT + Cit compared to the CON. However, the populations of entero-bacteria and fungi were not affected (p > 0.05) by the essential oils or their blends. For aerobic stability, we observed that Ros increased (p < 0.001) the air exposure time of the sorghum silage. Furthermore, the essential oils impacted the sorghum silage’s pH, which affected (p = 0.003) its aerobic stability. In conclusion, the essential oils did not reduce sorghum silage losses. However, the Ros improved the nutritional quality and aerobic stability of sorghum silage, while the blend Ros + TT + Cit increased the lactic acid bacteria count in the silage. More in-depth studies are needed to elucidate the action of essential oils as silage additives. Full article

Certain plants like Rosemarinus officinalis, Lavandula angustifolia and Origanum vulgare have been used in the food industry for centuries. Cymbopogon winterianus (Java Citronella plant) is one of the most significant plants. The objective of this study is to screen for secondary metabolites by phytochemical screening, evaluate the antioxidant contents of extracts and investigate the use of the Java Citronella plant in food preservation and as an insecticide. Java Citronella powder was added to bread and evaluated for its moisture content, and a visual and sensory analysis was performed. Sitophilus granarius (L.) weevils were exposed to Java Citronella essential oil (JCEO). The phytochemical screening revealed that the extracts were abundant in secondary metabolites. The JCEO had a yield of 0.75%. The aqueous extract had a higher total phenolic content of 49.043 ± 0.217 mg GAE/g than the ethanolic extract, which was 24.478 ± 1.956 mg GAE/g. The aqueous extract had a total flavonoids content 27,725.25 ± 54.96 µg RE/g higher than the ethanolic extract, with 24,263 ± 74 µg RE/g. The ethanolic extract had stronger antioxidant activity, with anIC₅₀ = 196.116 μg/mL higher than the aqueous extract at 420 μg/mL. The 2% Java Citronella powder in the bread was preferred by consumers, and had a shelf life of 6 days. JCEO killed all the weevils with a high dose of 10% after 48 h. The Java Citronella showed insecticidal and food preservative activity. The results should help in future research to enhance the applications of Java Citronella in various domains, from food technology to insecticides. Full article

One major problem with the overuse of antibiotics is that the microorganisms acquire resistance; thus the dose must be increased unsustainably. To overcome this problem, researchers from around the world are actively investigating new types of antimicrobials. Zinc oxide (ZnO) nanoparticles (NPs) have been proven to exhibit strong antimicrobial effects; moreover, the Food and Drugs Administration (FDA) considers ZnO as GRAS (generally recognized as safe). Many essential oils have antimicrobial activity and their components do not generate resistance over time. One of the drawbacks is the high volatility of some components, which diminishes the antimicrobial action as they are eliminated. The combination of ZnO NPs and essential oils can synergistically produce a stronger antimicrobial effect, and some of the volatile compounds can be retained on the nanoparticles’ surface, ensuring a better-lasting antimicrobial effect. The samples were characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), and thermal analysis (TG-DSC) coupled with analysis of evolved gases using FTIR. The ZnO NPs, with a size of ~35 nm, exhibited a loading between 1.44% and 15.62%—the lower values were specific for limonene-containing oils (e.g., orange, grapefruit, bergamot, or limette), while high values were obtained from cinnamon, minzol, thyme, citronella, and lavender oils—highlighting differences among non-polar terpenes and alcohol or aldehyde derivatives. The antibacterial assay indicated the existence of a synergic action among components and a high dependency on the percentage of loaded oil. Loaded nanoparticles offer immense potential for the development of materials with specific applications, such as wound dressings or food packaging. These nanoparticles can be utilized in scenarios where burst delivery is desired or when prolonged antibacterial activity is sought. Full article

The purpose of the current study was to prepare and evaluate a citronella oil-loaded microemulsion-based micro-emulgel for the treatment of Candida albicans. The primary objective was to use the skin to transfer hydrophobic medications into the bloodstream. The formulation included cinnamon oil as an antifungal oil and citronella oil as an active pharmaceutical ingredient, respectively. Tween 80 and PEG 200 were used as the surfactant and co-surfactant, respectively, to create phase diagrams. Carbopol 940, one of the frequently used polymers, was investigated for its ability to prepare gel formulations. The optimized (F3) batch contained the highest percentage (87.05 ± 0.03%) of drug content and, according to the statistics provided, had the highest drug release rate of around 87.05% within 4 h. The Korsmeyer–Peppas model with n value of 0.82, which is in the range 0.5–1, had the highest r² value, indicating that release following non-Fickian/anomalous diffusion provided a better dimension for all of the formulations. The optimized (F3) formulation had stronger antifungal activity in comparison to other formulations. This leads to the conclusion that citronella oil can be made into a micro-emulgel, which may improve its release in aqueous systems while maintaining a high level of drug release at the target site. Full article

The insertion of circular economy principles into the essential oil (EO) production chain aims to reduce waste generation and make integral use of harvested plant material. Higher profits from integral use with reduced waste generation contribute to the eventual use of the EO value chain as an alternative to illicit crops in Colombia (mostly coca). In this study, Java-type citronella (Cymbopogon winterianus) and palmarosa (C. martinii) plant materials were used in two consecutive processes to obtain EOs and extracts. The residual biomass after EO distillation was subjected to ultrasound-assisted hydroethanolic extraction to afford extracts that contained bioactive compounds. Citronella and palmarosa were distilled with typical EO yields (1.0 ± 0.1% for citronella; 0.41 ± 0.06% for palmarosa; n = 5) either through hydrodistillation assisted by microwave radiation or through steam distillation, and their composition (determined via GC/FID/MS analysis) and physicochemical parameters fell within their ISO standard specifications. The concentration of citronellal, the major compound of citronella oil, was 500 ± 152 mg/g. Geraniol, the main component of palmarosa oil, was found at 900 ± 55 mg/g. The citronella and palmarosa hydroalcoholic extracts (4–11% yield) were analyzed with UHPLC-ESI-Orbitrap-MS, which permitted the identification of 30 compounds, mainly C-glycosylated flavones and hydroxycinnamic acids. Both extracts had similar antioxidant activity values, evaluated using the ABTS^+● and ORAC assays (110 ± 44 µmol Trolox^®/g extract and 1300 ± 141 µmol Trolox^®/g extract, respectively). Full article

Indonesia’s vast forested areas have the potential to serve as a crucial source of livelihood for local communities. However, the current contributions of these forests to community livelihoods are significantly underutilized in comparison to their potential. This study evaluates the financial performance and sustainability of community forest-based businesses operating around the forest management area of the Lakitan-Bukit Cogong forest management unit (LBC FMU). Data were collected through semi-structured and in-depth interviews with the key informants through purposive sampling. Financial viability analysis and a qualitative approach were used to assess the feasibility of the businesses. The findings revealed that all businesses show positive values for all financial indicators. From profit estimation and value-added distribution, all products are shown to be feasible. Concerning the value and supply chain, the rubber-processing industry has a remarkable flow. Moreover, small forest enterprises (SFEs) highlight natural capital optimization through multitudinous derivatives of products that could support a substantial regenerative economy, including citronella essential oil, native honeybees, rubber-based product, biochar, skewers, and liquid smoke. In addition, the multidimensional scaling and rapid appraisal for forest (MDS-RAPForest) approach generates a result based on multiple dimensions (ecology, economics, social and human resources, and institutional and administrative dimensions) showing that overall, SFEs are categorized as sufficient/quite sustainable. Furthermore, mainstreaming adaptable forest-based enterprises, jurisdiction approaches, and cross-production system strategies are also discussed. Our findings suggest that sustainable NTFP-based activities within a community context can be facilitated through interconnected market systems, appropriate price regulations, and support from stakeholders and legal frameworks. Full article

This research serves as the basis for developing essential oil-based repellent activity tests against Aedes aegypti mosquitoes. The method used for the isolation of essential oils was the steam distillation method. Virus-free Aedes aegypti mosquitoes were used as test animals by applying the 10% essential oil repellent on the arms of volunteers. The analysis of the essential oils activities and aromas’ components was carried out using headspace repellent and GC-MS methods. Based on the results, the yields of essential oil from 5000 g samples for cinnamon bark, clove flowers, patchouli, nutmeg seed, lemongrass, citronella grass, and turmeric rhizome were 1.9%, 16%, 2.2%, 16.8%, 0.9%, 1.4%, and 6.8%, respectively. The activity test showed that the average repellent power of 10% essential oils, patchouli, cinnamon, nutmeg, turmeric, clove flowers, citronella grass, and lemongrass, was 95.2%, 83.8%, 71.4%, 94.7%, 71.4%, 80.4%, and 85%, respectively. Patchouli and cinnamon had the best average repellent power. Meanwhile, the aroma activities showed that the average repellent power of the patchouli oil was 96%, and the cinnamon oil was 94%. From the GC-MS analysis, nine components were identified in the patchouli essential oil aromas’ with the highest concentration being patchouli alcohol (42.7%), Azulene, 1,2,3,5,6,7,8,8a-octahydro-1,4-dimethyl-7-(1-methylethenyl)-, [1S-(1α,7α,8aβ)] (10.8%), α-guaiene (9.22%), and seychellene (8.19%)., whereas using the GC-MS headspace repellent method showed that there were seven components identified in the patchouli essential oil aroma with a high concentration of the components, which were patchouli alcohol (52.5%), Seychellene (5.2%), and α-guaiene (5.2%). The analysis results of cinnamon essential oil using the GC-MS method showed that there were five components identified in the aroma, with E-cinnamaldehyde (73%) being the highest component, whereas using the GC-MS headspace repellent method showed that there were five components identified in the aroma, with highest concentrations of cinnamaldehyde (86.1%). It can be concluded that the chemical compounds contained in patchouli and cinnamon bark have the potential to be environmentally friendly repellents in controlling and preventing Aedes aegypti mosquitoes. Full article

This work evaluated the synergistic effect of citronella essential oil (Ct) and montmorillonite (MMT) (called hybrid compound) incorporated in Poly(lactic acid) (PLA) films at different concentrations (3, 10, 15, and 20 wt%). PLA films were characterized using X-ray diffraction, SEM, TGA, and DSC considering their mechanical properties and essential oil migration. XRD analysis showed the effective interaction between MMT and oil. Thermal analysis, SEM, and mechanical tests were essential to understand the saturation point of the PLA composites. Samples with 15% and 20% of Ct showed a crystallinity reduction of 0.5% compared to samples with 3% and 10% of Ct. PLA/MMT–Ct showed a reduction in tensile strength of the order of 16 and 24, correlated to 15% and 20% of the Ct content, respectively, compared to PLA/MMT–Ct3%. Migration tests showed fast oil delivery correlated with high oil concentration, as evidenced using the PLA/MMT–Ct20% sample results, which showed an estimated release of 50% in the first 150 h due to system saturation, and the remaining being released in the last 350 h. Therefore, the migration tests provide an effective Ct concentration range promising for application with active packaging due to the intrinsic antimicrobial properties of Ct. Full article

Geraniol (GNL), a natural monoterpene, is found in many essential oils of fruits, vegetables, and herbs, including lavender, citronella, lemongrass, and other medicinal and aromatic plants. GNL is commonly used by the cosmetic and food industries and has shown a wide spectrum of pharmacological activities including anti-inflammatory, anticancer, antimicrobial, antioxidant, and neuroprotective activities. It represents a potential anti-inflammatory agent and a promising cancer chemopreventive agent, as it has been found to be effective against a broad range of cancers, including colon, prostate, breast, lung, skin, kidney, liver, and pancreatic cancer. Moreover, GNL scavenges free radicals and preserves the activity of antioxidant enzymes. In addition, GNL induces apoptosis and cell cycle arrest, modulates multiple molecular targets, including p53 and STAT3, activates caspases, and modulates inflammation via transcriptional regulation. In the present study, different modes of action are described for GNL’s activity against cancer and inflammatory diseases. This compound protects various antioxidant enzymes, such as catalase, glutathione-S-transferase, and glutathione peroxidase. Experiments using allergic encephalomyelitis, diabetes, asthma, and carcinogenesis models showed that GNL treatment had beneficial effects with low toxicity. GNL has been shown to be effective in animal models and tumor cell lines, but there have not been any clinical studies carried out for it. The aim of the present review is to provide updated data on the potential effects of GNL on cancer and inflammation, and to enhance our understanding of molecular targets, involved pathways, and the possible use of GNL for clinical studies and therapeutic purposes in the treatment of cancer and inflammation-related diseases. Full article

Cymbopogon nardus (citronella) essential oil (EO) has been widely used in the cosmetic and food industry due to its repellent and fumigant properties. The aim of this study was to evaluate its effects on the life cycle and midgut morphology of the natural predator Ceraeochrysa claveri. Larvae were fed on sugarcane borer eggs (Diatraea saccharalis) pretreated with citronella EO solutions (1–100 µg/mL in methanol, 5 s) or solvent and air-dried at room temperature for 30 min. Larval and pupal stage duration, the percentage of emergence of the insect, and malformed insects were recorded. One day after adults emerged from their cocoons, adult insects were used to obtain their midgut and analyzed using light microscopy. The chemical composition of C. nardus EO revealed that citronellal (25.3%), citronellol (17.9%), geraniol (11.6%), elemol (6.5%), δ-cadinone (3.6%), and germacrene D (3.4%) were the predominant compounds. Exposure to the EO produced a significant change in development duration for third instar and prepupa of the insect. The observed alterations in the lifecycle included prepupae with no cocoon formation, dead pupa inside the cocoon, and malformed adults. Several injuries in the midgut epithelium of exposed adults were registered, such as detachment of columnar cells leaving only swollen regenerative cells fixed on the basement membrane, and the formation of epithelial folds. In summary, these data suggest that C. nardus oil has adverse effects on the life cycle and midgut morphology of a beneficial predator. Full article