Antioxidant Activity Of Essential Oil Research Articles

Phytochemical analysis, antimicrobial and antioxidant activities of essential oils of the species Artemisia mesatlantica maire: in vitro and in silico approaches

ABSTRACT In the present work, we assessed the antioxidant, antibacterial, and antifungal activities of chemically defined Artemisia mesatlantica Maire (EOAM) essential oils. The GC-MS analysis of EOAM showed the presence of active promising active compounds. EOAM showed important antioxidant capacity through DPPH, FRAP and TAC assays. The in vitro antimicrobial screening showed that EOAM had antibacterial activity, with inhibition zones ranging from 20.67 to 38.35 mm on solid media and inhibitory doses of 2.34 to 4.78 µg/mL on liquid media. It also exhibits antifungal activities, with inhibition diameters ranging from 15.67 to 61.57 mm at doses from 2.90 to 12.54 µg/mL. EOAM was resistant to Aspergillus flavus (A. flavus). In addition, molecular docking, molecular dynamics simulations, and ADMET analyses validated in vitro activities. This research suggests that A. mesatlantica (EOAM) may fight drug-resistant bacteria. These results demonstrate the potential of EOAM to produce novel antioxidant and antibacterial solutions.

Study of essential oils and hydroalcoholic extracts obtained from Clinopodium vimineum (Lamiaceae), according to its different phenological stages

ABSTRACT The Caribbean shrub, Clinopodium vimineum, had its essential oil (EO) and hydroalcoholic extracts analyzed across three growth stages: vegetative, flowering, and post-flowering. The chemical composition of the EOs was analyzed by GC/MS/FID and that of the extracts was studied by UHPLC/ESI-Q-Orbitrap-MS. Twenty six compounds (>0.1%) were detected in the EOs of C. vimineum. p-Menth-3-en-8-ol (35–40%) and pulegone (27–30%) were the major components. Among the hydroalcoholic extracts, hydroxycinnamic acids (18–46 mg/g) and glycosylated flavones (17–19 mg/g) were found. The amounts of rosmarinic acid (20–40 mg/g) in the extracts isolated from the hydrodistillation residual biomass were twice as high as those in the extracts from the fresh plant material. The antioxidant activity of the EOs and extracts was evaluated by the ABTS+• and ORAC assays. No significant differences (p > 0.05) were found in the chemical composition or antioxidant activity of EOs and hydroalcoholic extracts, obtained from plants collected at different phenological stages.

Evaluation of the essential oil and tea produced from Baccharis myriocephala leaves

ABSTRACT Baccharis myriocephala is a carqueja species less studied than other Baccharis species. This study evaluated the chemical composition, toxicological and antioxidant potentials of the essential oils and infusions of B. myriocephala. Essential oils (hydrodistillation) and the volatile fractions of infusions (SPE) were analyzed by chromatographic techniques. The TPC and TFC of the infusions, and the antioxidant activities of essential oils and infusions were measured by spectrophotometry; their toxicological potentials were evaluated by Artemia salina bioassay (ASB). Twenty-eight terpenic compounds were identified in the essential oils, fourteen of them for the first time. Nine compounds were identified in the volatile fraction of the infusions, and seven of them were absent in essential oils. Infusions [IC50(DPPH) = 2.21 mg mL−1] are better antioxidants than the essential oils [IC50(DPPH) = 40.37 mg mL−1]. The essential oils were considered highly cytotoxic (LD50 = 26.64 μg mL−1), according to the ASB.

Wild Thymus zygis L. ssp. gracilis and Eucalyptus camaldulensis Dehnh.: Chemical composition, antioxidant and antibacterial activities of essential oils

Abstract Natural substances extracted from plants have been increasingly studied and recognized, recently. Essential oils (EOs), for example, possess antioxidant and antibacterial properties, enabling their application across different sectors like agro-food, pharmaceuticals, and cosmetics. In Morocco, exceptional plant diversity, mirroring the diversity of ecosystems, has not yet revealed all its secrets. Therefore, the aim of this study is to determine the chemical composition and evaluate the antibacterial and antioxidant activities of EOs from Thymus zygis L. ssp. gracilis and Eucalyptus camaldulensis Dehnh. collected in the El Hoceima and Mamora regions, respectively. The EOs were extracted by hydrodistillation employing a Clevenger-type apparatus. Gas chromatography/mass spectrometry (GC/MS) analyses identified 54 constituents representing 92.65% of the total for T. zygis and 55 components representing 99.60% for E. camaldulensis. The primary components found in the EO of T. zygis are δ-terpineol (27.64%), followed by δ-3-carene (15.7%), thymol (14.17%), and dehydrolinalool (4.99%). The main compounds in E. camaldulensis EO are 1,8-cineole (43.61%), γ-terpinene (11.71%), α-terpineol (10.58%), and p-cymene (4.93%). The antioxidant properties of these oils were investigated by utilization of the 2,2-diphenyl-1-picrylhydrazyl method and the ferric reducing antioxidant power (FRAP) test. The antibacterial activity was assessed against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Micrococcus luteus and Escherichia coli). Both EOs showed significant antioxidant activity but were less effective than reference antioxidants quercetin and catechin. Antibacterial studies demonstrated strong activity of T. zygis and E. camaldulensis EOs against the studied bacteria, as well as good inhibitory properties (minimum inhibitory concentration).

Chemical Compositions and In Vitro Antioxidant Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean Cryptomeria japonica (Cupressaceae).

In the Azores archipelago (Portugal), forest operations and wood industry generate large amounts of Cryptomeria japonica biomass residues (CJBR), which can be used to produce valuable essential oils (EOs). In this study, we evaluated the chemical composition and antioxidant activities of EOs from Azorean C. japonica sawdust (CJS) and resin-rich bark (CJRRB). The CJS and CJRRB EOs, obtained via hydrodistillation, showed different yield values (0.27% vs. 0.80% v/w, dry weight) and also different chemical profiles, as assessed using GC/MS. A total of 64 and 85 components were identified in CJS and CJRRB EOs, representing 95.7% and 96.9% of the total composition, respectively. The major components in CJS EO were oxygenated sesquiterpenes (mainly α+β-eudesmol, 1-epicubenol, and cubebol), while in CJRRB EO, the major components were monoterpene hydrocarbons, including α-pinene, δ-3-carene, and limonene (66.6% vs. 6.4% for oxygenated sesquiterpenes and 0% vs. 64% for monoterpene hydrocarbons, respectively). Antioxidant activity was estimated using (i) two radical-based assays, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and (ii) a lipid model assay, β-carotene-linoleic acid bleaching activity (BCBA). Both CJS and CJRRB EOs exhibited concentration-dependent antioxidant activities, and their DPPH, ABTS, and BCBA EC50 values were 1107 vs. 1275 µg/mL, 260 vs. 498 µg/mL, and 1764 vs. 662 µg/mL, respectively. The results indicate that both EOs were able to exert antioxidant activity via different mechanisms of action. Therefore, Azorean CJS and CJRRB may be sustainable sources for antioxidant compounds. This study expands the chemical and biological knowledge of CJBR EOs and, consequently, adds more value to the C. japonica EO industry.

Chemical Composition and Antioxidant Activity of Essential Oil from Leaves of Stigmaphyllon blanchetii

Chemical Composition and Antioxidant Activity of Essential Oil from Leaves of Stigmaphyllon blanchetii

Lyophilized Emulsions of Thymol and Eugenol Essential Oils Encapsulated in Cellulose.

Efforts to tap into the broad antimicrobial, insecticidal, and antioxidant activities of essential oils (EOs) are limited due to their strong odor and susceptibility to light and oxidation. Encapsulation of EOs and subsequent drying overcome these limitations and extend their applications. This study characterized freeze-dried (lyophilized) emulsions of eugenol (EU) and thymol (TY) EOs, encapsulated by chemically unmodified cellulose, a sustainable and low-cost resource. High-resolution scanning electron microscopy showed successful lyophilization. While the observed "flake-like" structure of the powders differed significantly from that of the emulsified microcapsules, useful properties were retained. Fourier transform infrared spectroscopy confirmed the presence of EOs in their corresponding powders and thermo-gravimetric analysis demonstrated high encapsulation efficiency (87-88%), improved thermal stability and resistance to evaporation, and slow EO release rates in comparison to their free forms. The lightweight and low-cost cellulose encapsulation, together with the results showing retained properties of the dried powder, enable the use of EOs in applications requiring high temperatures, such as EO incorporation into polymer films, that can be used to protect agricultural crops from microbial infections.

Physicochemical Characteristics, Chemical composition and In vitro Antioxidant activities of Essential oil from Ocimum basilicum L. Leaves

Physicochemical Characteristics, Chemical composition and In vitro Antioxidant activities of Essential oil from Ocimum basilicum L. Leaves

Chemical composition and biological activities of essential oils and extract of Eucalyptus citriodora Hook

In this study, the leaves of Eucalyptus citriodora Hook (Lemon-Scented Eucalyptus) were harvested and collected from Üzümlü neighborhood of Fethiye district of Muğla in 2021. Chemical content analysis of steam distillation and hydrodistillation of essential oils were determined by GC-MS, while phenolic content of methanol extract was determined by HPLC-DAD. Antioxidant activities of essential oils and methanol extracts were determined by DPPH radical removal, ABTS cation removal, β-carotene linoleic acid, and CUPRAC activity methods; Anticholinesterase activity against AChE and BChE enzymes was determined by Ellman method; and tyrosinase inhibition associated with melanin hyperpigmentation, α-amylase inhibition, and α-glucosidase inhibition activities associated with diabetes were determined as an in vitro. The bioactivities and chemical contents of E. citriodora species, a great value of, Türkiye, were determined, bringing new natural products to organic chemistry. As a result of the study, new bioactive extracts would be obtained and thus, they can effectively reveal the potential of new business opportunities. Since methanol extract is effective against incurable diseases such as Alzheimer's and diabetes, it will also be possible to develop therapeutics of such diseases by investigating the advanced chemistry and in vivo activities of the extracts with new projects.

Chemical characterization and antioxidant activities of essential oil of Ficus elastica Roxb. ex Hornem. leaves

The present study investigates the chemical constituents and antioxidant potential of essential oils extracted from Ficus elastica. The essential oils were obtained through steam distillation and were subjected to gas chromatography-mass spectrometry (GC-MS) analysis to determine their constituents representing 100% of the total peak areas. The analysis revealed the presence of 34 compounds. Among these compounds, Caryophyllene was found to be the major constituent, accounting for 50.57% of the total percentage area. Among other identified major compounds include γ-Muurolene (8.19%), camphene (5.69%), Heptacosane (2.61%), and Heneicosane (2.60%). Furthermore, the antioxidant potential of Ficus elastica essential oil was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide radical scavenging methods. The results indicated that F. elastica’s essential oil exhibited significant radical scavenging activity when compared to the standard antioxidant, Ascorbic acid. For the highest concentration tested (10 μL/mL), the DPPH scavenging inhibition percentage was 45.26% for F. elastica and 90.40% for Ascorbic acid. Similarly, the hydrogen peroxide scavenging activity at 10 μL/mL was found to be 74.90% for F. elastica and 90.12% for Ascorbic acid. Additionally, the essential oils demonstrated high radical scavenging and chelating activity. The quantitative DPPH and hydrogen peroxide assays indicate the potent antioxidant activity of F. elastica essential oil, making it a promising candidate for further biological and chemical analysis. The isolation of therapeutically active compounds from these essential oils can be pursued, considering their potential role in the management and treatment of various diseases.

Terpene Compound Composition and Antioxidant Activity of Essential Oils from Needles of Pinus densiflora, Pinus koraiensis, Abies holophylla, and Juniperus chinensis by Harvest Period

Plant resources are used as raw materials in various industries related to humans, such as edible, medicinal, taste, and flavor industries, depending on processes such as drying, processing, and collection period. In this study, we investigated the terpene compound composition and antioxidant activity of essential oils extracted from the needles of Pinus densiflora, Pinus koraiensis, Abies holophylla, and Juniperus chinensis collected in the harvest period (February, April, July, and October) planted on the campus of Chungbuk National University. The essential oil was separated by hydrodistillation. According to the analysis results of gas chromatography–mass spectrometry, the terpene compounds changed depending on the season and tree species. The proportions of monoterpene and sesquiterpene classes in the needles of P. densiflora, P. koraiensis, A. holophylla, and J. chinensis changed depending on the harvest period. The antioxidant activity by DPPH and ABTS assays varied depending on the species and seasons, and needles harvested from P. koraiensis showed the highest activity in all harvest periods. High antioxidant activity has been confirmed even at low concentrations in pine trees, so it is expected to play a role as a natural antioxidant. Additionally, since the composition of terpene compounds varies depending on the harvesting time and species, it is expected to have various uses in the pharmaceutical, cosmetics, and food industries.

Antioxidant Activity of Essential Oils Extracted from Apiaceae Family Plants

The importance of antioxidants has gained much attention due to the increase in the prevalence of various non-communicable diseases such as cancer, diabetes mellitus, and cardiovascular diseases, which occur due to excess reactive species. The widespread use of synthetic antioxidants in the food industry has raised concerns about their potential harmful effects on health. As a result, the utilization of natural antioxidants to preserve food and as a source of dietary antioxidants has gained attention. Essential oils extracted from Apiaceae family plants are an excellent source of antioxidants. In this review, research findings regarding the antioxidant activity of selected Apiaceae family members and their applications are discussed.

The Antioxidant Activity of Essential Oils in Edible Oils

The Antioxidant Activity of Essential Oils in Edible Oils

Antioxidant Activity of Essential Oils from Pinaceae Species.

With a widespread distribution throughout the Northern Hemisphere and 11 genera, Pinaceae is the largest family of Gymnosperms in the world. Essential oils are an important chemotaxonomic marker for the species of this family, although the degree of chemical and biological investigation has not been the same for all genera. Essential oils from Abies and Cedrus (from the abietoid clade) or Pinus and Picea (from the pinoid clade) have been more extensively investigated with respect to their chemical composition and biological or pharmacological properties, including their antioxidant effects. Instead, essential oils from the other genera of the family have been less explored in this respect or even have not been investigated at all. This is a narrative review looking into the knowledge acquired up to date, the variability and limitations of the current methods used to estimate antioxidant effects, and multiple comparisons between EOs obtained from different genera, species, and plant parts, as well as potential applications and future directions of research and utilization of essential oils derived from Pinaceae species.

Chemical Constituents and Antimicrobial and Antioxidant Activities of Essential Oil from Dried Seeds of Xylopia aethiopica.

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35%. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3%), β-pinene (14.8%), trans-pinocarveol (9.1%), myrtenol (8.3%), α-pinene (5.9%), and terpinen-4-ol (5.6%) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50 mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC50 = 784.604 ± 0.320 mg/mL) compared to that of ascorbic acid and the reference compound (IC50 = 0.163 ± 0.003 mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics.

Chemical composition, odor-active compounds and in vitro antioxidant activity of essential oils from leaves, fresh fruits and seed shells of Platycladus orientalis (L.) Franco

To investigate the volatiles and odor-active compounds (OACs) in essential oils (EOs) from leaves, fresh fruits and seed shells of Platycladus orientalis (L.) Franco, three EOs were extracted and analyzed by hydrodistillation combined with gas chromatography-mass spectrometry (GC-MS), gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and GC. The yields of three EOs were 0.22%, 0.48% and 1.94%, respectively; a total of 77 compounds were identified by comparing their mass spectra and retention index with those of the authentic standards or the related data reported in the references, and 29 odorants were determined as OACs. Among them, 58 volatile components were identified in the leaf EO, accounting for 98.19% of the total volatiles, of which 18 compounds were screened as OACs; 47 volatile components were determined in the fruit EO, representing 98.98% of the entire volatile oil, of which 12 compounds were sniffed as OACs; 49 volatiles were found in seed shell EO, covering 97.26% of the whole volatiles, of which 19 compounds were detected as OACs. OACs in three EOs were significantly different, and the odorants with higher concentrations included α-pinene, sabinene, δ-3-carene, myrcene, β-caryophyllene, α-terpinyl acetate, cedrol, etc., which could be used as indexes for optimizing extraction process parameters of POF EOs and evaluating EO quality. The in vitro antioxidant activity of three EOs was tested by DPPH assay, ABTS assay and FRAP assay.

GC/MS and LC-MS Analysis and in-vitro Antioxidant Activity of Essential Oil and Crude Methanol Extract from the Leaves of Acacia Gerrardii Benth. Growing in Saudi Arabia.

In this study, I determined the essential oil (EO) chemical composition and crude methanol extract (ME) phytochemical profile of the leaves of Acacia gerrardii (ACGL), a plant growing in Saudi Arabia. Additionally, I assessed their in vitro antioxidant activity. The gas chromatography-mass spectrometry analysis of the EO revealed a high content of oxygenated monoterpenes (79.86 %), primarily dominated by pulegone (35.11 %), carvacrol (27.36 %), and neo-dihydrocarveol (4.67 %). The ME was analyzed by liquid chromatography-mass spectrometry to determine its qualitative chemical profile. Four organic acids, eleven phenolic compounds, sixteen flavonoids, nine terpenoids (eight triterpenoids and one diterpenoid), and one coumarin were found in the ME of ACGL. This extract was found to be dominated by 5,6,4-trihydroxy-7,3-dimethoxyflavone (39.30 %), acteoside (30.27 %), nevadensin (7.55 %), isoacteoside (3.08 %) and apiin (3.23 %), and hesperidin (2.73 %). The phenolic (TPC=127.70±1.47 mg gallic acid equivalents/g of extract) and flavonoid (TFC=85.48±0.12 mg quercetin equivalents/g of extract) contents of the ME were also assessed. The in vitro antioxidant activities of both the EO and ME were evaluated using DPPH, ABTS, and ferrous ion chelating effect assays. Compared to the positive control (vit. E and Vit. C), and both extracts exhibited excellent activity.

Anticancer and antioxidant activities of essential oils of Chiliadenus iphionoides from Jordan: in vitro and in vivo study

Medicinal plants have been used since ancient times and may even be considered the origin of modern medicine. Natural products are a potential source for drug discovery and development of cancer treatments. Several pharmacological therapeutic activities were reported for Chiliadenus iphionoides. This research was designed to evaluate the essential oil of Chiliadenus iphionoides antioxidant potential and antiproliferative activity both in vitro and in vivo. The essential oil of Chiliadenus iphionoides was extracted by hydrodistillation. The chemical composition analysis was performed using gas chromatography. The main compounds identified in Chiliadenus iphionoides essential oil were oxygenated monoterpenes, such as eucalyptol (36.08%). A dose-dependent inhibition of cell proliferation was observed after the treatment of various cell lines (A549 (human lung cancer adenocarcinoma), MDA-MB-231 (triple-negative breast cancer cell line), T47 (human breast cancer cell line), EMT6/P (mouse mammary sarcoma cell line)) with increasing concentrations of the essential oil (0.02–2.5 mg/mL). The essential oil of Chiliadenus iphionoides was more cytotoxic against EMT6 and T47 cells with IC₅₀ values of 0.03±0.03 and 0.08± 0.009 mg/mL, respectively. The essential oil exhibited low cytotoxicity against a normal VERO cell line (IC₅₀ value > 4 mg/ml). Balb/C mice were inoculated with EMT6/p breast cancer cells and then treated with (60 mg/kg/day intraperitoneal injection) of essential extract for ten days. Interestingly, a significant (p < 0.05) reduction occurred in the tumor size of the treated group compared to the control group. Treatment toxicity was evaluated by measuring liver and kidney parameters. The tumor-bearing mice treated with the Chiliadenus iphionoides extract showed normal serum levels of AST, creatinine, and slight elevation in ALT level. The results indicated that Chiliadenus iphionoides have anticancer properties both in vitro and in vivo. We suggest that eucalyptol, a major active component, is a promising candidate for use as an anticancer agent. However, further molecular investigation is required to understand the molecular bearings of Chiliadenus iphionoides activity.

Salvia mirzayanii and Salvia hypoleuca Essential Oils: Chemical Composition, Alpha-Glucosidase Inhibitory, and Synergistic Effects of Selected Components

Background: Salvia is one of the most important genera belonging to the Lamiaceae family that has been used in various applications in folk medicine and the pharmaceutical and food industries. Objectives: This study investigated the chemical composition, antioxidant activity, and α-glucosidase inhibitory activity of Salvia mirzayanii Rech. f. and Esfand. and Salvia hypoleuca Benth. essential oils (EOs). Additionally, the enzyme inhibitory activity of the mixture of compounds was evaluated to find whether the synergistic effect is responsible for the desired activity or not. Methods: The constituents of S. mirzayanii and S. hypoleuca EOs collected from Fars and Alborz provinces, Iran, were determined using gas chromatography-mass spectroscopy (GC-MS) analysis. They were evaluated for their α-glucosidase inhibitory activity by the determination of para-nitrophenol (pNP), derived from the enzymatic degradation of para-nitrophenol-D-glucopyranoside (pNPG) as the substrate. The activity of the selected components was also tested. Moreover, the antioxidant activity of EOs was evaluated based on the radical scavenging capability (2,2-Diphenyl-1-picrylhydrazyl [DPPH]) assay, and their total phenolic content (TPC) was determined using the Folin-Ciocalteu method in terms of gallic acid equivalent (GAE). Results: In total, 66 compounds were detected in the S. mirzayanii and S. hypoleuca EOs. The results showed that S. mirzayanii EO had more potent antioxidant activity (half-maximal inhibitory concentration [IC50] = 0.77 ± 0.00 mg/mL), higher TPC (78.26 ± 1.26 mg GAE/g EO), and a greater inhibitory effect toward α-glucosidase (IC50 = 55.15 ± 1.60 mg/mL) than S. hypoleuca EO. Furthermore, caryophyllene oxide (IC50 = 19.94 ± 0.26 mg/mL), α-pinene (IC50 = 17.59 ± 0.19 mg/mL), and linalool (IC50 = 38.00 ± 0.22 mg/mL) showed high levels of α-glucosidase inhibitory activity among the major constituents. In addition, the combination of linalool: 1,8-cineole: α-terpineol (40: 35: 25) inhibited this enzyme synergistically (combination index [CI] < 1). Conclusions: The findings indicated that S. mirzayanii EO had a high potential for developing efficient anti-type 2 diabetes agents.

Chemical profile and radical scavenging of the Psidium guajava flower’s essential oil: Molecular docking study on the human cytochrome P450 CYP2C9

Psidium guajava L. plant is frequently utilized as therapeutic plant due to its nutritional benefits and bioactive metabolites. The current study intends to identify the chemical characterization and antioxidant activity of essential oil (EO) of freshly harvested P. guajava flowers. The EO was analyzed using GC with flame-ionization detection (FID), gas chromatography-mass spectrometry (GC-MS) along with chemometric analysis. With 98.87% of overall oil mass, 37 volatile constituents were assigned. All identified compounds were categorized into two classes including mono-(30.34%) and sesquiterpenes (68.53%). The d-limonene (26.10%), trans-β-caryophyllene (17.24%), trans-nerolidol (11.01%), and ledol (5.12%) served as predominant compounds. Using three separate methods, DPPH, ABTS, and reducing power, the free radical scavenging activity of P. guajava flower oil was assessed in comparison with ascorbic acid as a reference antioxidant. The net results revealed that EO has considerable activities with respective IC50 values of 224.53, 125.78, and 231.78 mg L−1. All main compounds (> 3.00%) were in silico studied by Molecular Operating Environment (MOE) software on human cytochrome P450 CYP2C9. The net findings showed that the tested compounds have good binding affinity ranging from ΔG at −4.43 to −5.65 kcal/mol, while ascorbic acid exhibits binding affinity with ΔG = −4.58 kcal/mol. Cubenol revealed the best binding affinity with ΔG = −5.65 kcal/ mol. The present findings verified the guava flower EO’s powerful functions. For a better knowledge of the action pathways both in vitro and in vivo, more scientific studies on this oil’s antioxidant and/or its main components in pure form were advised.