Orange Oil Research Articles

Active cardboard box with palm wood waste powder and orange oil to prevent browning and quality loss in cabbage: Mode of action and potential for reuse.

Browning, caused by enzymatic activity and storage conditions, affects cabbage during cold storage and is crucial for customer acceptance. This study investigated the effect of cardboard packaging containing low concentrations of nano-orange oil (ONE) at 0.006% in palm wood waste powder for anti-browning and extending the shelf life of cabbage. The incorporation of ONE into palm wood powder (PWP) using different methods (soaking, vapor, vapor with ultrasonic device, and control) was examined before using the active PWP to develop cardboard cabbage packaging. The reuse of the active cabbage box packaging was also investigated for up to three reuses. The results showed that a greater anti-browning effect was achieved with cardboard packaging made from active PWP with orange oil vapor and an ultrasonic device compared to other adsorption methods, with significantly higher inhibition of the key browning enzyme activities of polyphenol oxidase (PPO) and peroxidase (POD). Additionally, antioxidant activity and bioactive compounds were improved, maintaining the bright green color of cabbage after 21 days of storage. The shelf life of cabbage stored in active cardboard was extended to at least 21 days compared to 5 days for the control. The active cabbage box with PWP and ONE vapor with an ultrasonic device showed potential for reuse at least two times. Limonene was found on the surface of stored cabbage and may be a key factor in antimicrobial activity, helping to control microbial growth on the cabbage surface within standard limits during long-term storage. This finding provides valuable guidance for reducing cabbage waste during transportation and storage from farm to market. PRACTICAL APPLICATION: This research offers new insights into active cardboard packaging made from palm wood powder with a low concentration of orange oil vapor to prevent browning and microbial growth in storage boxes. The optimal method for producing this packaging uses nano-orange oil vapor at 0.006% with an ultrasonic device, which could be feasible for large-scale production. The packaging effectively reduced PPO and POD enzyme activity, delaying browning and extending cabbage shelf life by at least threefold compared to the control, while maintaining color and freshness. This cost-effective method promotes the sustainable use of agricultural waste in the fresh vegetable industry, as it can be reused at least twice, benefiting farmers and reducing cabbage waste.

Bambara groundnut starch-soluble dietary fibre nanocomposite stabilised emulsions: Optimisation of emulsion stability and studies on time-dependent rheological properties

Due to their inherent thermodynamic instability, emulsions require stabilisers to maintain their integrity and prevent destabilisation. The effect of emulsion components (Bambara groundnut starch-soluble dietary fibre nanocomposite (STASOL), orange oil and water) on the rheological and stability properties of STASOL-stabilised emulsions was optimised. A randomised D-optimal exchange mixture design was used to determine the ratio of STASOL, orange oil and water required for a stable emulsion. The stability of these emulsions was evaluated using the initial mean backscattering index (BSAVO), Turbiscan stability index (TSI) and hysteresis loop area (HLA). The BSAVO (%), TSI and HLA of the emulsions ranged from 50.73% (14:30:56 STASOL:oil:water) to 70.47% (20:30:50 STASOL:oil:water), 0.0005 (20:30:50 STASOL:oil:water) to 0.1000 (8:42:50 STASOL:oil:water) and 0.37 Pas-1 (10:32:58 STASOL:oil:water) to 5.69 Pas-1 (20:30:50 STASOL:oil:water), respectively. Emulsions exhibited a direct relationship between STASOL concentration and stability metrics, with the highest stability achieved at 20% STASOL concentration, 30% orange oil and 50% water. An increase in STASOL concentration coupled with a decrease in oil concentration results in a stable emulsion. Numerical optimisation and experimental validation confirmed the effectiveness of the selected formulation, demonstrating STASOL's potential as a natural stabiliser in beverage emulsions and its ability to enhance stability compared to synthetic alternatives.

Revealing the off-flavors in hydro-distilled essential oils of sweet orange (Citrus sinensis) by flavoromics strategy and computational simulation

Citrus essential oils (EOs) are renowned for their aroma, but thermal extraction methods can introduce undesirable cooking and pungent odors. The specific compounds responsible for these off-flavors and their perception mechanisms remain unclear. This study investigated the flavor differences between cold pressing (CP) and hydro-distilled (HD) extracted essential oils from sweet oranges (SEOs) using flavoromics strategy. The results indicated that increased levels of alcohol compounds, particularly terpinen-4-ol, β-citronellol, geraniol, trans-carveol, and α-terpineol, were primarily responsible for the off-flavors in HD-extracted SEOs. Furthermore, molecular docking and dynamics simulations revealed that off-flavor compounds bind to olfactory receptors through hydrogen bonding and hydrophobic interactions, inducing slight structural and conformational changes that facilitate odor recognition and activate downstream signaling events. This study offers crucial insights into the mechanisms underlying off-flavor development in citrus EOs, providing valuable knowledge for optimizing extraction methods, controlling SEOs quality, and advancing flavor science.

Antifungal Activity of Citrus Essential Oil in Controlling Sour Rot in Tahiti Acid Lime Fruits.

Sour rot, caused by Geotrichum citri-aurantii, is a significant post-harvest disease in citrus, resulting in economic losses due to the lack of effective fungicides. This study investigates the antifungal activity of citrus essential oils in controlling sour rot in Tahiti acid lime fruits. Essential oils were extracted via hydrodistillation with chemical composition analyzed by CG-MS and tested in vitro and in vivo. In vitro assays evaluated mycelial growth inhibition at 2 to 32 µL mL-1 concentrations. In vivo trials involved preventive and curative treatments on artificially inoculated fruits stored at 25 °C ± 2, and the results showed that Pera IAC sweet orange oil, at 32 µL mL-1, reduced disease severity by 96% in curative treatments. In contrast, Late IAC 585 willowleaf mandarin oil demonstrated moderate inhibition (44%) at the highest concentration in vitro. The oils did not affect key fruit quality parameters such as juice yield and total soluble solids. These findings suggest that citrus essential oils could be natural alternatives to synthetic fungicides for post-harvest sour rot management, combining effectiveness with maintaining fruit quality.

Formulation and evaluation of herbal makeup primer

The burgeoning interest in natural and sustainable beauty products has driven the development of herbal makeup primers, which combine cosmetic functionality with the benefits of botanical ingredients. This abstract explores the formulation, efficacy, and advantages of herbal makeup primers. Unlike traditional primers that often rely on synthetic chemicals, herbal primers leverage plant-based extracts known for their skin-enhancing properties, such as aloe Vera& Orange oil. These ingredients offer soothing, anti-inflammatory, and antioxidant benefits that can improve skin texture and promote a healthier complexion. The formulation of herbal makeup primers typically includes a blend of herbal extracts, essential oils, and natural emulsifiers. These components work synergistically to create a smooth base for makeup application while also addressing skin concerns such as redness, dryness, and uneven tone. Clinical and consumer studies suggest that herbal primers can enhance makeup longevity and performance, while simultaneously contributing to overall skin health. In summary, herbal makeup primers represent a significant advancement in cosmetics science by integrating the therapeutic benefits of herbal ingredients into everyday beauty routines. Their growing popularity underscores a shift towards more eco-friendly and skin-conscious beauty solutions, aligning with consumer demand for products that offer both cosmetic and therapeutic benefits. Future research and development in this field are likely to expand the range of available formulations and further validate the efficacy of these natural alternatives.

Toxicity Test of Essential Oil from Kintamani Slayer Orange Peel (Citrus Reticulata) With Zero Waste Application to Support Ecotourism

Kintamani slayer orange peel can be extracted into essential oil because it contains terpenoids, sesquiterpenoids, alkanes, alkyl alkanoates, and steroid alcohols. Orange peel contains active substances that can help heal wounds, such as essential oils, ascorbic acid, vitamin E, vitamin A, flavonoids, and polyphenols, and has antioxidant and antibacterial activity. Kintamani orange peel contains flavonoids, alkaloids, saponins, tannins, terpenoids, and essential oils. The main goal of this study is to identify the waste by-product characteristics of Kintamani slayer orange peel in order to achieve zero waste. Essential oils in Kintamani slayer orange peel (Citrus reticulata) are toxic to Artemia salina Leach shrimp larvae. The GC results on Kintamani slayer orange peel essential oil obtained twelve (12) compound peaks

Possibility for control with botanical insecticides against the mealy plum aphid Hyalopterus pruni Geoffroy, 1762 (Hemiptera: Aphididae) on the plum in Southern Bulgaria

The aim of this study was to evaluate the efficacy of botanical insecticides recommended for control of the mealy plum aphid Hyalopterus pruni (Hemiptera: Aphididae). The experiment was carried out in 2024 in the experimental field of the Fruit Growing Institute-Plovdiv, Bulgaria. The tested insecticides were orange oil (Limocid), liquid extract of Urtica spp. (Basictec) and pyrethrins (Abanto). The insecticides were applied at the recommended concentrations for control of aphids, whiteflies, thrips and other pests. All tested botanical insecticides showed high biological efficacy and can be used to control the mealy plum aphid. Keywords: mealy plum aphid, biological control, botanical insecticides, Limocid, Basictec, Abanto, Hyalopterus pruni

Population Dynamic of Aphis gossypii, and Their Parasitoids, and Effect of Some Insecticides on Aphids, Chlorophyll Content, Non-Enzymatic and Antioxidant Enzymes Activity in Cantaloupe Leaves in Greenhouses

Under green house, the Population density of Aphis gossypii on cantaloupe plants recorded two peaks on May 9th and 23th with 1409 and 1561 individuals/ 10 leaves in season 2022, while one highest peak, on 16th May with 1650 individuals/ 10 leaves in season 2023. Parasitism status of Aphidius colemani and Lysiphlebus fabarum varied from 1.49% on 25 April to 35.79% on 9th of May with seasonal parasitism 2023 in 2022 and ranged between 0.73% on 25th of April and 30.06% on 16th of May with seasonal parasitism 16.57% in 2023. Acetamiprid, imidacloprid, imidacloprid + abamectin, jojoba oil, orange oil and thiamethoxam + abamectin compounds were tested to control aphids during two seasons. Imidacloprid recorded the highest reduction with all average 97.88 ±1.15 and 97.39 ±1.15 in the first and second season respectively. the highest mean reduction of emergence of the two-parasites caused by thiamethoxam + abamectin by 16.92% followed by Imidacloprid with 16.87%. While the least toxicity to emergence of the parasitoids recorded with jojoba oil 0.0% followed by orange oil 1.93% in season 2022, while in season 2023, the higher parasitoid reduction caused by acetamiprid 18.05% followed by Imidacloprid 17.69% and thiamethoxam + abamectin 17.53%. Chlorophyll content increased with treatment jojoba oil followed by Imidacloprid by 47.91 and 44.73 unit in the first season and Thiamethoxam with abamectin lead to the highest content by 44.05 unit in the leaves followed by jojoba oil with 43.65 unit. The least treatment was Imidacloprid + abamectin with 39.55 unit compared with control treatment 40.43 unit. Treatment Thiamethoxam + abamectin recorded the highest content of carbohydrates (48.43) compared with control (47.71). Treatments of insecticides led to increase of protein, fats and total lipid compared with control. Also, Antioxidant enzymes activity in cantaloupe leaves were found to be increased in the treatment of insecticides compared with control.

Antimicrobial and antioxidant properties of essential oils from orange peels and eucalyptus leaves wastes

Oranges and eucalyptus trees are abundant sources of waste and pruning, generating secondary streams that can be converted into valuable products. Both species are broadly cultivated in Mexico. Essential oils from orange peels and eucalyptus leaves possess antimicrobial and antioxidant properties, making them useful in various applications. In this study, the essential oils antioxidant potential was determined through radical scavenging activity and ferric reducing capacity, and the total phenolic content was measured. These essential oils also demonstrated inhibition capacity against Escherichia coli and Staphylococcus aureus. GC-MS analysis of the oils revealed the composition of representative compounds, with D-limonene constituting almost 75% of the orange essential oil and 1,8-cineol comprising 15.2% of the eucalyptus oil. The antioxidant test results between essential oils showed that they are similar, except for the FRAP test, where eucalyptus essential oil obtained a value three times higher than orange essential oil. The findings suggest that these essential oils can serve as natural and sustainable alternatives to synthetic antimicrobial and antioxidant agents.

Characterization of PLA/PCL biocomposite food packaging film using orange peel essential oil bio-plasticizer and lignin biocompatibilizer

Characterization of PLA/PCL biocomposite food packaging film using orange peel essential oil bio-plasticizer and lignin biocompatibilizer

Biochemical and histological analysis of ethanol peel extract of Citrus sinensis on mercury chloride-induced prefrontal cortex damage in Wistar rats

Mercury is one of the heavy metals which is found extensively in many environmental and certain occupational settings. It is the third most dangerous heavy metal and its toxicity causes serious risks to health through unfavorable pathological and biochemical effects. Sweet orange is the fruit of the citrus species (Citrus sinensis) in the family Rutaceae.. Over time there has been increasing interest in the utilization of these peels for both nutritional and medicinal purposes. Studies have reported the antioxidant potential of orange peel oil in laboratory rodents, indicating its protective effect against oxidative stress-mediated ailments. The study evaluated the effect of ethanolic extract of Citrus sinensis peel on mercury chloride-induced changes in the prefrontal cortex of adult Wistar rats. Twenty-five Wistar rats were purchased and divided into five groups containing five animals in each group. Group 1 was administered with distilled water, Group 2, Group 3, Group 4, and Group 5 were administered with 5 mg/kg of mercury chloride only, 5 mg/kg of mercury chloride and 140 mg/kg Silymarin, 5 mg/kg mercury chloride and 1000 mg/kg of ethanoic extract of orange peel, and 5 mg/kg mercury chloride and 1500 mg/kg of ethanoic extract of orange peel. All administration was done orally and the administration lasted for 14 days. The animals were sacrificed humanely using 75 mg/kg ketamine intraperitoneally and prefrontal was dissected out. Part was homogenized in 0.1M phosphate buffered saline for the estimation of superoxide dismutase (SOD), and catalase (CAT) activities, and Malondialdehyde (MDA) level and the other part was fixed by immersion in 10 neutral buffered formal-saline for histological evaluation. The results indicate that the MDA level in control Group(13.29±1.183 μmol) is statistically significantly lower compared to the Group 2 (21.88±1.96 μmol), group 3 (27.44±3.52 μmol), Group 4 (22.20±1.16 μmol) and Group 5 (25.40±3.13 μmol). No statistically significant different that was observed in SOD activity. It CAT activities in control group (53.51±6.83 nmol/ml) is statistically significantly lower compared to the group 2 (26.21±3.70 nmol/ml), Group 3 (27.17±5.32 nmol/ml), Group 4 (25.30±4.24 nmol/ml) and Group5 (26.59±4.22 nmol/ml). Protective role of the extract was observed from the histological evaluation. This study suggests that ethanolic extract of Citrus sinensis peel have protective effects on mercury-induced changes in prelimbic part of the prefrontal cortex of adult Wistar rats.

Effectiveness of Chloroform and Orange Oil as Gutta-percha Solvents used in Endodontic Retreatment: An In Vitro Study

The aim of this study was to assess and compare the effectiveness of chloroform and orange oil to dissolve obturated materials during endodontic retreatment. Thirty extracted human permanent maxillary anterior teeth (10 central incisor, 10 lateral incisor and 10 canine) which fulfilled specific inclusion criteria were de-coronated and after biomechanical preparation using step-back technique obturated with gutta-percha and AH plus sealer and stored in 370C in 100% humidity for 2 weeks. Then the teeth were assigned into 2 groups randomly: Chloroform (n= 15) and Orange oil (n= 15). Solvents were applied to reservoir created on the coronal root third for 2 minutes. Then instrumentation was initiated to remove obturated materials using Hedstrom file until the master apical file size 40 for central incisor and canine and 35 for lateral incisor reach the working length. The time to reach the working length and the time to obtain the last debris were recorded. Data were collected and analyzed by using SPSS version 22. The results showed no statistically significant difference (P>0.05) between two gutta-percha solvent groups in relation to time required to reach the working length by master apical file and time required to remove total obturated material from root canal. In conclusion, there was no statistically significant difference in effectiveness between chloroform and orange oil as gutta-percha solvent during retreatment procedure. So, orange oil can be used in retreatment procedure with the same efficacy of chloroform to dissolve obturated material in the root canal.

Retraction Note: Detailed analysis on exploiting the low viscous waste orange peel oil and improving its usability by adding renewable additive: waste to energy initiative

Retraction Note: Detailed analysis on exploiting the low viscous waste orange peel oil and improving its usability by adding renewable additive: waste to energy initiative

Sustainable Management of Tetranychus urticae and Trialeurodes vaporariorum on Tomato and Cucumber Plants Using Rhamnolipids and Essential Oil-Based Biocontrol Agents.

Rhamnolipids (RLs), biosurfactants produced by Pseudomonas aeruginosa, have gained attention for their potential role in pest management. This study investigated the efficacy of RLs in controlling the two-spotted spider mite (Tetranychus urticae) and the whitefly (Trialeurodes vaporariorum), as well as a novel non-commercial essential oil-based product, Petir Kilat, on cucumber and tomato plants within a controlled greenhouse environment. The RLs were tested at concentrations of 1 mL/L and 2 mL/L, compared to commercial biopesticides including abamectin (ABAMAX) and Beauveria bassiana (NATURALIS). The results indicated that ABAMAX achieved the highest mortality rates for T. urticae and T. vaporariorum, with 100% mortality observed at 7 days. NATURALIS was also highly effective, particularly for whiteflies, though its efficacy declined over time. RLs showed a dose-dependent increase in mortality, with the higher concentration (2 mL/L) yielding more promising results, though not surpassing the commercial products. Petir Kilat, derived from orange essential oils, demonstrated significant control, particularly at higher concentrations, comparable to or exceeding the effectiveness of NATURALIS and ABAMAX in some cases. Statistical analyses revealed significant differences between treatments in most cases (p < 0.05). The findings underscore the potential of RLs and Petir Kilat as components of integrated pest management (IPM) strategies. While RLs are effective, their performance suggests they are best used in combination with other control methods. The study highlights the need for further research to optimize the application of RLs and essential oil-based products to enhance their role in sustainable pest management practices.

Curcumin-Loaded Organogel for The Topical Skin Disorder Based on 12 Hydroxystearic Acid

Curcumin (CUR) possesses various pharmacological properties, including antibacterial and improving injury healing. This work aimed to formulate curcumin organogel using 12 hydroxy stearic acid as gelator with tween 80 as surfactant and PEG 400 as co surfactant to improve the CUR permeation through the skin. The CUR organogels were prepared using different 12HSA concentrations with solvents sesame oil (SO), and orange oil (OO), in addition to T80 and P400 and evaluated for their saturated solubility, tabletop rheology, oil binding capacity, pH, spreadability, in vitro release, antibacterial activity, oscillatory rheology study, skin irritation, histological examination and ex- with in- vivo permeation study across rat abdominal skin. Results: The important results that distinguished organogels were the spreadability and in vitro release studies. The 4SO, 2OO, 2T80, and 10P400 organogels presented successful gelation and represented the lowest 12HSA concentration in each solvent that approached the current aim’s study by being more spreadable with higher CUR released. At the same time, the 2T80 and 10P400 gave zones of inhibition to 4 bacterial strains and good viscoelasticity by exhibiting large flow point values in the frequency sweep study compared with 4SO and 2OO. In vivo study affirmed the CUR permeation by studying the fluorescent images of 2T80 and 10P400, and the ex vivo permeation study for 10P400 proved the CUR permeation through rat’s skinOur results indicated the potential of 10P400 and 2T80 organogel to improve the topical therapeutic efficacy of CUR.

Antifungal potential of essential oils from different botanical sources against Penicillium digitatum: chemical composition and antifungal mechanisms of action by direct contact and volatile

Fungal deterioration is a recurring problem in citrus fruits, and the search for natural preservatives has been widely publicised. Therefore, the in vitro antifungal activity of clove, white thyme, tea tree, Eucalyptus citriodora, Eucalyptus staigeriana, green mandarin, sicilian lemon, sweet orange, and bergamot essential oils (EO’s) was evaluated against the mycelial growth of Penicillium digitatum isolated from contaminated citrus fruits, by direct contact and volatiles action. In addition, the chemical composition and volatile compounds of the EO’s were evaluated by gas chromatography. Clove, white thyme, and Eucalyptus citriodora EO’s inhibited 100% of the mycelial growth of P. digitatum by direct contact and volatile action at concentrations ≤ 2 µL/mL. On the other hand, EO’s from citrus sources could not inhibit 100% of mycelial growth by any mechanism of action. Thus, the clove, thyme, and Eucalyptus citriodora EO’s are promising for developing new ecologically correct products for controlling phytopathogens in citrus fruits.

Resin Acid Copper Salt, an Interesting Chemical Pesticide, Controls Rice Bacterial Leaf Blight by Regulating Bacterial Biofilm, Motility, and Extracellular Enzymes.

Bacterial virulence plays an important role in infection. Antibacterial virulence factors are effective for preventing crop bacterial diseases. Resin acid copper salt as an effective inhibitor exhibited excellent anti-Xanthomonas oryzae pv. oryzae (Xoo) activity with an EC50 of 50.0 μg mL-1. Resin acid copper salt (RACS) can reduce extracellular polysaccharides' (EPS's) biosynthesis by down-regulating gumB relative expression. RACS can also effectively inhibit the bio-mass of Xoo biofilm. It can reduce the activity of Xoo extracellular amylase at a concentration of 100 μg mL-1. Meanwhile, the results of virtual computing suggested that RACS is an enzyme inhibitor. RACS displayed good curative activity with a control effect of 38.5%. Furthermore, the result of the phytotoxicity assessment revealed that RACS exhibited slight toxicity compared with the control at a concentration of 200 μg mL-1. The curative effect was increased to 45.0% using an additional antimicrobial agent like orange peel essential oil. RACS markedly inhibited bacterial pathogenicity at a concentration of 100 μg mL-1 in vivo.

Impact of Solvent Properties of Cold-Pressed and Steam-Distilled Orange Oils on GuttaFlow2 and Gutta-Percha.

Root canal retreatment often employs organic solvents like chloroform, eucalyptol, and orange oil. However, studies comparing their effectiveness yield inconsistent results. The quantity of d-limonene, a crucial component in orange oil, varies depending on the oil production method. Cold-pressed orange oil has been observed to contain the highest d-limonene levels. This study investigates the comparative solvent effects of cold-pressed and steam-hydrodistilled orange oils on gutta-percha and GuttaFlow2, typically used components in root canal fillings. Thirty-two discs (10 mm in diameter and 2 mm in thickness) were prepared using GuttaFlow and gutta-percha cones. The samples were weighed and then randomly divided into four groups (n=8) based on the type of solvent used. Each group was immersed in its respective solvent for 10 minutes. After exposure to the solvent, the samples were reweighed to determine the amount of material removed. The weight loss in the group treated with cold-pressed orange oil on gutta-percha was significantly higher than in other groups (GuttaFlow2 + cold-pressed orange oil, gutta-percha + steam hydrodistilled orange oil, GuttaFlow2 + steam hydrodistilled orange oil) (p<0.001, p<0.001, and p<0.001). According to the study findings, cold-pressed orange oil demonstrated a higher solvent effect on both GuttaFlow2 and traditional gutta-percha compared to steam-hydrodistilled orange oil. This indicates the significant impact of the production method of orange oil on its efficacy as a solvent in root canal therapy retreatment.

Identification of characteristic compounds of sweet orange oil and their sweetening effects on the sucrose solution with sweetness meter, sensory analysis, electronic tongue, and molecular dynamics simulation

The characteristic aroma compounds of five-fold sweet orange oil were analyzed using gas chromatography–mass spectrometry combined with the odor aroma value (OAV) method. The results indicated that limonene, linalool, dodecanol, (E,E)-2,4-decadienal, (E)-citral, linalool, (E)-2-decenal, and geraniol are important contributors. The sweetening effects of key compounds on sucrose solutions were experimentally investigated. The results showed that the sweetness effects of five compounds (limonene, citronellal, geraniol, β-sinensal and β-caryophyllene) were better than those of (E)-citral, linalool and octanal. Molecular dynamics implied that the hydrogen bonding residues of the T1R2/T1R3-sucrose system were converted from LYS65, GLU302, ASP278, and SER144 to ASP278, SER144, ASP142, and ASP213 after the addition of limonene. Meanwhile, the hydrophobic interaction forces of the system are significantly enhanced. The total energy of the T1R2/T1R3-sucrose system decreased from −32.08 kcal/mol to −63.57 kcal/mol. The synergistic sweetening mechanism of characteristic aroma compounds of sweet orange oil on sucrose was revealed.

Enantioselective Detection of (D)- and (L)-Limonene from Essential Oil Samples Using a Molecularly Imprinted Polypyrrole Electrochemical Sensor

Limonene is a monoterpene compound that has two enantiomers, (D)- and (L)-limonene, in different quantities and proportions in several essential oils, and it is used in the chemical, pharmaceutical, and food industries. While the (D)-limonene is widely found in citrus, the (L)-limonene is found mainly in oils of Pinus and Mentha. The enantioselective detection holds the fact that the two isomers are found together in different quantities, in which each has its properties. The preferential use of one depends on the purpose, (D)-limonene is used in the pharmaceutical and chemical industry, while (L)-limonene has organoleptic properties and is used in the food industry, cosmetic, and personal hygiene industries. The methods existing in the literature involve the detection of the enantiomers by gas chromatography-mass spectrometry and high-performance liquid chromatography. Since the two enantiomers can be found together in different samples, is very important to have a simple and faster method to determine both. This work aims to develop an electrochemical sensor using a “dual template” technique, with both limonene enantiomers and a monomer (pyrrole), forming a molecularly imprinted polymer (MIP) film and determining the analyte “one-by-one”, by saturating the cavities of one specific enantiomer to determine the other one, using differential pulse voltammetry (DPV). This is the first electrochemical sensor for the enantioselective determination of (D) and (L)-limonene. Initially, a suspension of 0.4 mg mL-1 of graphene oxide in 0.1 mol L-1 of Na2SO4 solution was directly reduced on a glassy carbon electrode surface through chronoamperometry, applying a potential of -1.4 V for 500s. Then, AuNPs were electrodeposited from a 5.0×10-4 mol L-1 HAuCL solution in 0.5 mol L-1 H2SO4 onto the GCE/rGO electrode, also through chronoamperometry, in which a potential of 0.4 V was applied until the charge of 1.0x10-3 C was reached. Next, for the electropolymerization process, a solution containing 3.0x10-2 mol L-1 pyrrole and both (D)- and (L)-limonene enantiomers in a phosphate buffer solution (pH 7.0), was used in 5 consecutive voltammetric cycles on the GCE/rGO/AuNPS electrode, applying a potential range from 0.0 to 1.0 V in a scan rate of 0.02 V s-1, forming the MIP film. The extraction of the template molecules involved the application of 5 consecutive voltammetric cycles in NaOH 0.1 mol L-1 in a potential range from 0.0 to 1.5 V (0.05 V s-1). For the rebinding process, the electrode was placed for five minutes in different concentrations of one specific enantiomer after saturation of the other one, in PB solution pH 7.0. All the experimental parameters that influence the analytical performance of the device were optimized, such as pyrrole concentration, electropolymerization and extraction cycles, rebinding times, electropolymerization and rebinding pH, and nanoparticle charge. The electrode was characterized by scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry. The analytical methodology was developed, with a limit of detection (LOD) for (D)-limonene of 1.8x10-12 mol L-1, a limit of quantification (LOQ) of 5.5x10-12 mol L-1, and an amperometric sensibility (AS) of 5.8x105 A L mol-1. For the (L)- enantiomer, the LOD, LOQ, and AS are 1.4x10-12 mol L-1, 4.3x10-12 mol L-1, and 6.2 A L mol-1, respectively. The linear range is from 2.0x10-12 to 1.0x10-11 mol L-1 for both enantiomers. It was analyzed the stability and repeatability inter and intra-day of the sensor. The selectivity study of both analytes was evaluated with the imprinted factor (α) and the selectivity factor (β) with different molecules present in the sample, showing that the sensor is capable of selectively recognizing limonene. Furthermore, this method was applied to real samples of the essential oil of orange (Citrus aurantium), the essential oil of peppermint (Mentha piperita), and the essential oil of Siberian pine (Abies sibirica). The quantification of (D)- and (L)-limonene was successfully performed using the standard addition method and the results obtained were validated by recovery assays. All relative standard deviations were below 5%. These results indicate that the proposed sensor exhibits good analytical performance, being suitable for the determination of both limonene enantiomers in essential oils.Acknowledgements:São Paulo Research Foundation (FAPESP) (Grants: 2023/00817-9 and 2017/22401-8)