Concentrations Of Eugenol Research Articles

Eugenol rescues the TRPV1-dependent inhibition of KCNQ2/3.

Transient receptor potential vanilloid 1 (TRPV1) is expressed predominantly in peripheral nociceptors integrating diverse noxious stimuli. Activation of TRPV1 leads to a cascade of pro-nociceptive mechanisms, particularly, TRPV1 activation can inhibit the slow activating KCNQ2/3 current, the inhibition apparently depends on the A-kinase anchoring protein 5 (AKAP5) expression, forming a pro-nociceptive multiprotein complex. Eugenol is an aromatic oil extracted from cloves and widely used for dental pain treatment. It features multiple functions and regulate diverse ion channels. By using electrophysiological recordings on HEK293 cells, we show that eugenol is a weak activator of the TRPV1 but functions as an antagonist because it competes with capsaicin for the same binding pocket attenuating the TRPV1 current. Eugenol also serves as an activator of the KCNQ2/3 channels, shifting the voltage-dependent activation to negative voltages (−15 mV) and accelerating the activation kinetics by >3 fold. Eugenol does not show preference for KCNQ2 or KCNQ3. In cells expressing the multiprotein complex, application of a low concentration of capsaicin (100 nM) for 5 minutes, reproduces the TRPV1-dependent inhibition of KCNQ2/3, but it is prevented by the presence of high concentrations of eugenol. These data suggests that eugenol provides an inhibitory control for noxious stimuli in sensory neurons, by antagonizing TRPV1 and lowering the activation threshold of KCNQ2/3, silencing the neurons.

The pharmacokinetic and residue depletion study of eugenol in carp (Cyprinus carpio).

The pharmacokinetic profile and residue depletion of eugenol in carp (Cyprinus carpio) tissues and plasma were performed by a convenient and reliable high-performance liquid chromatography (HPLC) method. The eugenol in carp tissues and plasma was extracted with a mixed solution of acetonitrile and methanol. N-hexane was used to remove lipid impurities. The method was successfully applied to the pharmacokinetic and residue elimination of eugenol in carp after the carp was administered a medicated bath. The average recoveries of eugenol in tissues and plasma fortified with four concentration levels were 69.0-106.6% and 80.0-86.7%, respectively. The relative standard deviations were < 8.9%. The limit of detection (LOD) was 0.01 μg/g in tissue and 0.008 μg/ml in plasma, respectively. The pharmacokinetic parameter of Cmax for eugenol in plasma at the concentrations of 20, 35, and 75 mg/L were 10.86, 17.21, and 37.32 mg/L, respectively. The t1/2 values were 3.68, 4.22, and 9.31 h. After the investigation of the anesthetic effect, 35 mg/L of eugenol was the optimal concentration for anesthesia. The highest accumulation concentration of eugenol in carp is in the liver and the lowest is in the muscle. In addition, the eugenol in tissue was eliminated rapidly and at a lower level than the LOD at 48 h. According to the residue elimination, the withdrawal time of eugenol was suggested at 5.2 days. These results indicate that the developed method had good linearity and accuracy, and is sensitive enough for the monitoring of eugenol residue in carp. The half-life of eugenol decreased with the increase in drug concentration and the eugenol was eliminated rapidly in carp tissues. 35 mg/L eugenol was recommended as an anesthetic in carp due to its favorable anesthetic effect and no mortality. This study will contribute to the establishment of MRL regulation and setting a withdrawal period.

An Update on the Therapeutic Anticancer Potential of Ocimum sanctum L.: "Elixir of Life".

In most cases, cancer develops due to abnormal cell growth and subsequent tumour formation. Due to significant constraints with current treatments, natural compounds are being explored as potential alternatives. There are now around 30 natural compounds under clinical trials for the treatment of cancer. Tulsi, or Holy Basil, of the genus Ocimum, is one of the most widely available and cost-effective medicinal plants. In India, the tulsi plant has deep religious and medicinal significance. Tulsi essential oil contains a valuable source of bioactive compounds, such as camphor, eucalyptol, eugenol, alpha-bisabolene, beta-bisabolene, and beta-caryophyllene. These compounds are proposed to be responsible for the antimicrobial properties of the leaf extracts. The anticancer effects of tulsi (Ocimum sanctum L.) have earned it the title of "queen of herbs" and "Elixir of Life" in Ayurvedic treatment. Tulsi leaves, which have high concentrations of eugenol, have been shown to have anticancer properties. In a various cancers, eugenol exerts its antitumour effects through a number of different mechanisms. In light of this, the current review focuses on the anticancer benefits of tulsi and its primary phytoconstituent, eugenol, as apotential therapeutic agent against a wide range of cancer types. In recent years, tulsi has gained popularity due to its anticancer properties. In ongoing clinical trials, a number of tulsi plant compounds are being evaluated for their potential anticancer effects. This article discusses anticancer, chemopreventive, and antioxidant effects of tulsi.

Eugenol; Effective Anthelmintic Compound against Foodborne Parasite Trichinella spiralis Muscle Larvae and Adult.

Trichinosis is a foodborne parasitic infection that results from ingestion of raw or under-cooked pork meat infected by parasitic nematode Trichinella spiralis with cosmopolitan distribution. Anthelmintic drugs are used to eliminate intestinal adult parasites and larvae as well as tissue-migrating newborn and in-turn encysted larvae. However, eliminating the infection or averting it from transmission is rarely possible using anthelmintic groups of benzimidazole derivatives. Eugenol (EO) is the main extracted constituent of clove oil (80-90%) and is responsible for its aroma. Therefore, this study aims to investigate the effect of eugenol on both adult and muscle larvae of Trichinella spiralis in vitro. IC50 for different concentrations of eugenol were calculated for both muscle larvae (187.5 µM) and adults (190.4 µM) to determine the accurate dose range. Both the nematode stages were cultured in the commonly used RPMI-1640 media in 24-well plates. Different concentrations of eugenol (122, 305, 609, 1218, and 3045 µM) were administered in different groups of larvae/adults. The parasitological parameters were monitored after 1, 3, 6, 10, 24 h for each EO concentration in concomitant with the control groups. Reference chemotherapeutic anthelminthic drug "albendazole" (at dose 377 µM) was experimentally grouped in triplicates as positive control and the untreated as negative control, respectively. Mortality was observed where time-dependent adult stages were less susceptible than muscle larvae. Eugenol achieved 100% efficacy against T. spiralis larvae and killed the total larvae after 10 and 24 h at concentrations of 1218 and 3045 µM, the same as albendazole's effect on the positive control group. In regard to adults, resembling muscle larvae (ML), a significant effect of both concentrations at p &lt; 0.0001 was obtained, and the concentration × time interaction was significant at p &lt; 0.0001. Furthermore, the treated/untreated adult and muscle larvae were collected and processed for scanning electron microscopy (SEM). Massive destruction of parasite burden was observed, especially at high concentrations (1218 and 3045 µM). In addition, complete and mild loss in cuticular striation in both the treated and positive controls were confirmed by SEM, respectively, in comparison to the control untreated group.

RP-HPLC Method Development and Validation for Simultaneous Estimation of Thymol, Eugenol and Alliin in Bulk and Novel Nanoformulation

A rapid and simple HPLC method was developed to detect and quantify Thymol, Eugenol and Alliin being the potential components of Ajwain oil, Clove oil and Garlic oil respectively in herbal formulation. Liquid chromatography with a UV detector at a wavelength of 278nm, using a C18 column, was employed in this study. Isocratic elution was employed using a mixture of acetonitrile: methanol:10mM Phosphoric acid buffer (50:25:25, v/v, pH 3.0). The analytical method validation was performed in accordance with ICH guidelines, which included selectivity, range, linearity, accuracy, detection limit, quantitation limit, precision, robustness, and stability of solutions. Acceptable assay precision and accuracy (100±2.0%) were obtained at 50– 150% of the analytical concentration of Thymol, Eugenol and Alliin at the target concentration, and good linearity (0.999, 0.998 and 0.998 respectively) were achieved over a range of 10µg/mL -60µg/mL for Thymol and Eugenol and 0.25µg/mL –1.50µg/mL for Alliin. The proposed HPLC method proved to be reliable. The validation and application of this method can be adopted and used in the pharmaceutical industry for routine analysis.

Comparison of eugenol and dihydromyricetin loaded nanofibers by electro-blowing spinning for active packaging

To explore the dihydromyricetin or eugenol loaded nanofiber's potential as food active packaging, 0%, 0.1%, 0.5%, and 1.0% dihydromyricetin or eugenol loaded nanofibers were fabricated by electro-blowing spinning, which increased the yield of nanofibers by a factor of 10 times compared to that of traditional electrospinning. The morphology observation by scanning electron microscopy showed similar morphology and diameter distribution of the dihydromyricetin or eugenol nanofibers. Fourier transform infrared spectra analysis indicated that eugenol or dihydromyricetin interacted with proteins through hydrogen bonding. X-ray diffraction profiles of the nanofibers indicated that dihydromyricetin was uniformly distributed within the nanofibers. Nanofibers encapsulated with various concentrations of eugenol or dihydromyricetin showed better barrier properties against water vapors than the free nanofibers, which indicated that the hydrophobic eugenol and dihydromyricetin inhibited the permeation of water molecules through the nanofibers. Tensile tests showed that the nanofibers loaded with 0.5% eugenol or 1.0% dihydromyricetin exhibited relatively higher elastic moduli and lower elongation at break. The nanofibers loaded with dihydromyricetin showed comparable antioxidant activity to that with eugenol in the aspect of ferric and cupper reducing activity, while that with 0.1%–1.0% dihydromyricetin showed superior DPPH radical scavenging activity. Furthermore, both eugenol and dihydromyricetin loaded gelatin/zein nanofibers showed effective antimicrobial activities against Escherichia coli and Staphylococcus aureus. Overall, the dihydromyricetin loaded gelatin/zein nanofibers showed comparable physical and functional properties compared to eugenol, which suggests the application of dihydromyricetin nanofibrous films on food active packaging and the potential application of dihydromyricetin on functional food delivery systems.

Candida albicans Reactive Oxygen Species (ROS)-Dependent Lethality and ROS-Independent Hyphal and Biofilm Inhibition by Eugenol and Citral.

Candida albicans is part of the normal human flora but is most frequently isolated as the causative opportunistic pathogen of candidiasis. Plant-based essential oils and their components have been extensively studied as antimicrobials, but their antimicrobial impacts are poorly understood. Phenylpropenoids and monoterpenes, for example, eugenol from clove and citral from lemon grass, are potent antifungals against a wide range of pathogens. We report the cellular response of C. albicans to eugenol and citral, alone and combined, using biochemical and microscopic assays. The MICs of eugenol and citral were 1,000 and 256 μg/mL, respectively, with the two exhibiting additive effects based on a fractional inhibitory concentration index of 0.83 ± 0.14. High concentrations of eugenol caused membrane damage, oxidative stress, vacuole segregation, microtubule dysfunction and cell cycle arrest at the G1/S phase, and while citral had similar impacts, they were reactive oxygen species (ROS) independent. At sublethal concentrations (1/2 to 1/4 MIC), both oils disrupted microtubules and hyphal and biofilm formation in an ROS-independent manner. While both compounds disrupt the cell membrane, eugenol had a greater impact on membrane dysfunction. This study shows that eugenol and citral can induce vacuole and microtubule dysfunction, along with the inhibition of hyphal and biofilm formation. IMPORTANCE Candida albicans is a normal resident on and in the human body that can cause relatively benign infections. However, when our immune system is severely compromised (e.g., cancer chemotherapy patients) or underdeveloped (e.g., newborns), this fungus can become a deadly pathogen, infecting the bloodstream and organs. Since there are only a few effective antifungal agents that can be used to combat fungal infections, these fungi have been exposed to them over and over again, allowing the fungi to develop resistance. Instead of developing antifungal agents that kill the fungi, some of which have undesirable side effects on the human host, researchers have proposed to target the fungal traits that make the fungus more virulent. Here, we show how two components of plant-based essential oils, eugenol and citral, are effective inhibitors of C. albicans virulence traits.

Enhanced inhibition of Pseudomonas aeruginosa virulence factor production and biofilm development by sublethal concentrations of eugenol and phenyllactic acid.

Biofilm development in Pseudomonas aeruginosa is regulated by its quorum sensing (QS) systems. It has three major QS systems: LasI/R, RhlI/R and PQS/MvfR. Previous studies showed that phenyllactic acid (PLA) binds to RhlR and PqsR and inhibits the Rhl and PQS QS; and eugenol at sublethal concentration inhibits Las and PQS QS systems. Here, we have demonstrated that a combination of sublethal doses of eugenol and PLA enhanced the inhibition of the QS mediated production of the virulence factors and biofilm development of this pathogen. A combination of 50 μmol l-1 eugenol and 0·3 mmol l-1 PLA significantly inhibited the pyocyanin production, protease activity, swarming motility and cytotoxic activities of P. aeruginosa strain PAO1, whereas eugenol and PLA when added individually to PAO1 cultures were less effective in inhibiting its virulence factor expression. Biofilm formation of PAO1 was reduced by 32, 19 and 87% on glass surfaces; and 54, 49 and 93% on catheter surfaces when treated using 50 μmol l-1 eugenol or 0·3 mmol l-1 PLA and their combinations, respectively. The invitro finding in the reduction of biofilm development was further validated invivo using a catheter associated medaka fish biofilm model. Our results indicate that a combination of QS inhibitors targeting different QS pathways should be selected while designing therapeutic molecules to achieve maximum QS mediated biofilm inhibition and clinical outcome against P. aeruginosa.

Antibacterial Mechanism of Eugenol Against Shigella sonnei and Its Antibacterial Application in Lettuce Juice.

Shigella sonnei is a species of Shigella, and the infection rate of S. sonnei is increasing year by year. Eugenol is an active ingredient in clove essential oil and is a generally recognized as safe (GRAS)-certified food ingredient. The mechanism of inhibition of S. sonnei by eugenol has been investigated in this study. The minimum inhibitory concentration of eugenol against both S. sonnei ATCC 25931 and S. sonnei CMCC 51592 was 0.5 mg/mL and minimum bactericidal concentration (MBC) for both strains was 0.8 mg/mL. The inhibition effect of eugenol against S. sonnei was due to increased levels of reactive oxygen species in cells, changed cell membrane permeability, and induced cell membrane dysfunction, for instance, cell membrane hyperpolarization and intracellular ATP concentration drops. The results of confocal laser scanning microscope and field emission scanning electron microscopy showed that eugenol leads to decreased cell membrane integrity, resulting in changed cell morphology. Moreover, eugenol inactivated S. sonnei in Luria-Bertani (LB) broth and lettuce juice. These results indicated that eugenol could inactivate S. sonnei and has the potential to control S. sonnei in the food industry.

Eugenol and geraniol impede Csu-pilus assembly and evades multidrug-resistant Acinetobacter baumannii biofilms: In-vitro and in-silico evidence

Acinetobacter baumannii forms robust biofilms, which aid protection against antimicrobials and account for adaptation in hospital settings. Biofilm formation by A. baumannii has worsens the scenario of drug resistance. Therefore, new strategies are required to tackle biofilm-forming multidrug-resistant A. baumannii. The present study investigated compounds with antimicrobials and antibiofilm properties against A. baumannii. Different antimicrobials were selected from available reports. Initially, comparative antimicrobial activity against A. baumannii isolates was assessed. Most potent antimicrobial compounds were further analyzed for time-kill kinetics, biofilm inhibition, and exopolysaccharide (EPS) reduction in their presence and absence. The antibiofilm potentials were also confirmed with SEM analysis. The relative gene expression of the csuE gene and molecular docking was carried out to investigate the molecular mechanism of mature biofilm disruption. The results demonstrated eugenol and geraniol as the most potent inhibitors with MICs of 6.08 mM and 3.24 mM, respectively, with the potential to significantly inhibit growth and EPS production. Complete inhibition of A. baumannii mature biofilms was observed with a maximum of 60.89 mM and 129.6 mM concentrations of eugenol and geraniol, respectively. The SEM analysis and lower expression of the csuE gene showed the effectiveness of potent antibiofilm agents. In-silico docking showed efficient binding of eugenol and geraniol with the csuE protein of archaic pilus. The findings of molecular docking concordant the assumption that these molecules may prevent the assembly of mature pilus, which results in abolished biofilms. In conclusion, the antibiofilm virtues of eugenol and geraniol were elucidated to be used in the future to control the persistence of biofilm-forming drug-resistant A. baumannii.

Effects of Eugenol on Water Quality and the Metabolism and Antioxidant Capacity of Juvenile Greater Amberjack (Seriola dumerili) under Simulated Transport Conditions.

Simple SummaryThe transportation of live fish is a very important part of the aquaculture system. The health status of fish can be affected in the closed-container transportation system. It has become very common to relieve the stress of fish in transport by adding anesthetics. With the food safety of fish having gained widespread attention, the addition of plant extracts as an alternative to anesthetics has become an important research topic. The objective of this study was to evaluate the effects of eugenol addition during simulated transport on water quality, and the metabolism and antioxidant capacity of liver and gills in the greater amberjack (Seriola dumerili). It was found that the addition of eugenol under simulated transport conditions had positive effects on water quality, and on liver and gill metabolism and antioxidant capacity in the greater amberjack. This study contributes to the healthy culture of the greater amberjack.This study investigated the effects of added eugenol on water quality and the metabolism and antioxidant capacity of the liver and gills of the greater amberjack (Seriola dumerili) during simulated transport. The juvenile fish (10.34 ± 1.33 g) were transported in sealed plastic bags containing different eugenol concentrations at a density of 24.79 kg/m3 for 8 h. The different eugenol concentrations were divided into five groups: 0 μL/mL (control group), 0.0125 μL/mL, 0.025 μL/mL, 0.0375 μL/mL, and 0.05 μL/mL, with three replicates of each. The results showed that 0.05 μL/mL of eugenol could significantly increase dissolved oxygen, but 0.025 μL/mL–0.0375 μL/mL resulted in a significant decrease in dissolved oxygen and significant increases in NH4+-N and NO2−-N. It was found that 0.05 μL/mL of eugenol caused significant up-regulation of the relative expression of CPT-1 in the liver, significant down-regulation of the relative expression of FAS and PK in the liver and gills, a significant increase in glycogen concentration, and a significant decrease in glucose concentration. This suggests that 0.05 μL/mL of eugenol could reduce the metabolic capacity of fish. In addition, 0.05 μL/mL of eugenol caused significant up-regulation of the relative expression of CAT and a significant decrease of MDA concentration in the liver. Meanwhile, the gills showed significant up-regulation of CAT relative expression, significant down-regulation of Keap1 relative expression, and a significant increase in GSH activity, resulting in a significant increase in MDA concentration when the concentration of eugenol reached or exceeded 0.025 μL/mL. This suggests that 0.05 μL/mL eugenol could improve the antioxidant capacity of fish and lipid peroxidation levels in the gills. In conclusion, the addition of 0.05 μL/mL eugenol could improve water quality, and the metabolic and antioxidant capacities of liver and gills, but it could also increase lipid peroxidation levels in the gills under transport conditions.

Enhanced vanillin production from eugenol by Bacillus cereus NCIM-5727.

Biovanillin production by a wild strain of Bacillus cereus NCIM-5727 is studied using eugenol as the precursor aiming to achieve maximum vanillin productivity. Based on shake flask optimization, molar yield and global volumetric productivity of vanillin reached up to 71.2% (6.6 gL-1) and 0.18g(Lh)-1, respectively, at 36h by resting cells of B. cereus NCIM-5727 at the optimum cell concentration of 3 gL-1 using eugenol concentration of 10 gL-1 at 37 ºC, buffer pH 7.0, buffer volume 10%, and shaking speed 180rpm. Furthermore, small-scale optimization in a bioreactor at the controlled aeration rate of 0.5 Lmin-1, agitation rate of 210rpm, and pH 7.0 enhanced the global volumetric productivity of vanillin up to 0.28g(Lh)-1 at 25h of bioconversion. The highest vanillin molar yield (75.2%) is reported using resting cells of B. cereus NCIM-5727 upon eugenol biotransformation and found stable for 10h.

Alteration in Light Spectra Causes Opposite Responses in Volatile Phenylpropanoids and Terpenoids Compared with Phenolic Acids in Sweet Basil (Ocimum basilicum) Leaves.

Basil (Ocimum basilicum, cv. Dolly) grew under three different light spectra (A, B, and C) created by light-emitting diode lamps. The proportions of UV-A, blue, and green-yellow wavelengths decreased linearly from A to C, and the proportions of red and far-red wavelengths increased from A to C. Photosynthetic photon flux density was 300 μmol m–2 s–1 in all spectra. The spectrum C plants had highest concentrations of phenolic acids (main compounds: rosmarinic acid and cichoric acid), lowest concentrations and emissions of phenylpropanoid eugenol and terpenoids (main compounds: linalool and 1,8-cineole), highest dry weight, and lowest water content. Conversely, spectra A and B caused higher terpenoid and eugenol concentrations and emissions and lower concentrations of phenolic acids. High density of peltate glandular trichomes explained high terpenoid and eugenol concentrations and emissions. Basil growth and secondary compounds affecting aroma and taste can be modified by altering light spectra; however, increasing terpenoids and phenylpropanoids decreases phenolic acids and growth and vice versa.

Combination of Poly(ε-Caprolactone) Biomaterials and Essential Oils to Achieve Anti-Bacterial and Osteo-Proliferative Properties for 3D-Scaffolds in Regenerative Medicine.

Biomedical implants, an essential part of the medical treatments, still suffer from bacterial infections that hamper patients’ recovery and lives. Antibiotics are widely used to cure those infections but brought antibiotic resistance. Essential oils (EOs) demonstrate excellent antimicrobial activity and low resistance development risk. However, EO application in medicine is still quite scarce and almost no research work considers its use in combination with bioresorbable biomaterials, such as the poly(ε-caprolactone) (PCL) polymer. This work aimed to combine the antibacterial properties of EOs and their components, particularly eugenol and cinnamon oil, against Staphylococcus aureus, S. epidermidis and Escherichia coli, with those of PCL for medical applications in which good tissue regeneration and antimicrobial effects are required. The PCL porous scaffolds, added with increasing (from 30% to 50%) concentrations of eugenol and cinnamon oil, were characterized by square-shaped macropores. Saos-2 cells’ cell viability/proliferation was hampered by 40 and 50% EO-enriched PCL, whereas no cytotoxic effect was recorded for both 30% EO-added PCL and pure-PCL. The antibacterial tests revealed the presence of a small inhibition halo around the 30% eugenol and cinnamon oil-functionalized PCL scaffolds only for staphylococci, whereas a significant decrease on both adherent and planktonic bacteria was recorded for all the three microorganisms, thus proving that, even if the EOs are only in part released by the EO-added PCL scaffolds, an anti-adhesive feature is anyway achieved. The scaffold will have the ability to support new tissue formation and simultaneously will be able to prevent post-surgical infection. This research shows the great potential in the use of EOs or their single components, at low concentrations, for biomaterial functionalization with enhanced anti-bacterial and biointegration properties.

Quantitative Analysis of Eugenol in Different Parts of Clove

Eugenol is the key active constituent of clove. The aim of this study was to analyze the concentration of Eugenol in different parts of dried Clove (tail, mid body and flower) by IR Spectroscopy and graphical comparison of the concentration. In this experiment the different part of dried clove was used to perform the quantitative analysis. Two methods were followed for the IR Spectroscopy, Attenuated Total Reflectance (ATR) sampling method and KBr Pellet method. KBr Pellets were prepared at 1:99 (Clove part: KBr) and IR spectrum drawn between IR reason (650 to 4000). Total 5 samples were analysed [Sample 01- Clove flower, Sample 02- just below of flower, Sample 03- mid body, Sample 4 -mid Body 2nd and Sample 05 -tail part]. Two wavelengths were target 1513 cm-1 and 1431 cm-1. The quantitative analysis was performed for % transmittance and % absorbance. Plotted Spectra was compared with the Spectral Database for Organic Compounds (SDOC) and spectra-base at Wiley. Sample 03 mid body shows higher area comparatively remaining four samples at both peaks (1513 cm-1 as well as 1431 cm-1). Results shows that the concentration of Eugenol is higher at Ovules than tail and flower.

Eugenol Inhibits the Biological Activities of an Oral Squamous Cell Carcinoma Cell Line SCC9 via Targeting MIF.

Oral squamous cell carcinoma (OSCC) is a rampant cancer type in head and neck cancers with a poor prognosis and a high recurrence rate. Eugenol shows an anticancer effect in a variety of cancers, but it has been rarely studied in oral squamous cell carcinoma (OSCC). The purpose of this study was to explore the role of Eugenol in OSCC and the underlying mechanism. After different concentrations of Eugenol (0, 200, 400, and 800 μM) treatment, the viability, proliferation, migration, and invasion of OSCC cell line SCC9 were measured by CCK-8, colony formation, wound-healing, and transwell assays, respectively. TUNEL staining was employed to detect apoptosis. Western blotting was used to evaluate gene expression at the protein level. Molecular docking was used to identify the target of Eugenol. Eugenol decreased the proliferation and reduced the abilities of invasion and migration along with the expression of matrix metalloproteinases (MMP) 2 and MMP9 in SCC9 cells. On the contrary, the ratio of apoptotic cells was increased by Eugenol. In addition, Eugenol down-regulated B cell lymphoma-2 (Bcl-2) expression, but up-regulated BCL-2 associated X (Bax), cleaved caspase 3, and cleaved poly-ADP ribose polymerase (PARP) expression. Meanwhile, Eugenol exerted its effect on SCC9 cells in a concentration-dependent manner. Eugenol could bind to macrophage migration inhibitory factor (MIF), the expression of which was down-regulated after Eugenol treatment. Besides, overexpression of MIF reversed all the effects of Eugenol on OSCC cells. In summary, Eugenol suppressed the malignant processes of OSCC cells by targeting MIF, which could guide the clinical application of Eugenol in OSCC.

Basil seedling production environment influences subsequent yield and flavor compound concentration during greenhouse production.

Radiation intensity and carbon dioxide (CO2) concentration can be precisely controlled to manipulate plant yield and quality. Due to increased plant densities during seedling production, fewer inputs per plant are required, creating the potential to increase production efficiency. Therefore, the objectives of this research were to: 1) quantify the extent radiation intensity and CO2 concentration under sole-source lighting influence morphology and yield of sweet basil (Ocimum basilicum) seedlings, and 2) determine if differences in morphology, yield, and volatile organic compound (VOC) concentration persist after transplant in a common environment. Sweet basil ‘Nufar’ seedlings were grown in growth chambers with target CO2 concentrations of 500 or 1,000 μmol·mol‒1 under light-emitting diodes (LEDs) providing target photosynthetic photon flux densities (PPFD) of 100, 200, 400, or 600 μmol·m‒2·s‒1 for 16 h per day. After two weeks, seedlings were transplanted into a common greenhouse environment and grown until harvest. At transplant and three weeks after transplant (harvest), growth and developmental differences were quantified along with key terpenoid and phenylpropanoid concentrations at harvest. Radiation intensity and CO2 interacted influencing many aspects of plant morphology, though CO2 concentration effects were less pronounced than those of radiation intensity. As radiation intensity during seedling production increased from 100 to 600 μmol·m‒2·s‒1, basil seedlings were 38% taller, had a 713% larger leaf area, and had 65% thicker stems; at harvest, plants were 24% taller, had 56% more branches, 28% more nodes, 22% thicker stems, and weighed 80% more when fresh and dry. Additionally, after growing in a common environment for three weeks, eugenol concentration was greater in plants grown under a PPFD of 600 μmol·m‒2·s‒1 as seedlings compared to lower intensities. Therefore, increasing radiation intensity during seedling production under sole-source lighting can carry over to increase subsequent yield and eugenol concentration during finished production.

Antibacterial Effect of Eugenol on Shigella flexneri and Its Mechanism.

Shigella flexneri (Sh. flexneri), which can be found in food and the environment, is a widespread food-borne pathogen that causes human diarrhea termed “shigellosis”. In this study, eugenol, a natural active substance, was investigated for its antibacterial activity against Sh. flexneri. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of eugenol against Sh. flexneri ATCC 12022 was 0.5 and 0.8 mg/mL. The growth curves and inhibitory effect in LB broth, PBS, vegetable juice, and minced pork showed that eugenol had a good activity against Sh. flexneri. Research findings indicated the superoxide dismutase activity of Sh. flexneri was inhibited after eugenol treatment, resulting in concentrations of intracellular reactive oxygen species and an increase in malondialdehyde. The flow cytometry analysis and field emission scanning electron microscopy results revealed obvious damage to cell membrane integrity and changes in the morphology of Sh. flexneri. In addition, the intracellular ATP concentration leaked from 0.5 μM to below 0.05 μM and the membrane potential showed a concentration-dependent depolarization after eugenol treatment. In summary, eugenol exerted strong antibacterial activity and has the potential to control Sh. flexneri in the food industry.

Eugenol reduces serum testosterone levels and sperm viability in adult Wistar rats

Eugenol is the main constituent of clove extract. It is a remarkably versatile molecule incorporated as a functional ingredient in several food products and widely applied in the pharmaceutical industry. Men consume natural products enriched with eugenol for treating sexual disorders and using as aphrodisiacs. Nevertheless, there is no information about the impact of eugenol intake on the reproductive parameters of healthy males. Therefore, we provided 10, 20, and 40 mg kg-1 pure eugenol to adult Wistar rats for 60 days. Testis, epididymis, and spermatozoa were analyzed under microscopic, biochemical, and functional approaches. This phenolic compound did not alter testicular and epididymal biometry and microscopy. However, 20 and 40 mg kg-1 eugenol reduced serum testosterone levels. The highest dose altered lactate and glucose concentrations in the epididymis. All the eugenol concentrations diminished CAT activity and MDA levels in the testis and increased FRAP and CAT activity in the epididymis. Epididymal sperm from rats receiving 10, 20, and 40 mg kg-1 eugenol presented high Ca2+ ATPase activity and low motility. In conclusion, eugenol at low and high doses negatively impacted the competence of epididymal sperm and modified oxidative parameters in male organs, with no influence on their microscopy.

Oocyte in vitro maturation with eugenol improves the medium antioxidant capacity and total cell number per blastocyst

This study investigates the impact of eugenol (EU) supplementation on bovine oocyte in vitro maturation (IVM) and antioxidant capacity, as well as in vitro embryo production and quality after conventional in vitro fertilization (IVF). A total of 1077 cumulus oocyte complexes were cultured in TCM-199+ without EU supplementation (control treatment) or supplemented with EU at the concentrations of 10 μM (EU-10), 20 μM (EU-20), or 40 μM (EU-40). After IVM, the oocytes were subjected to IVF and embryo culture. The addition of EU at 40 μM to the IVM medium improved (P < 0.05) the antioxidant capacity and cleavage rate when compared to the control treatment. Moreover, a positive correlation (r = 0.61, P < 0.03) was observed between cleavage rate and EU concentration. The addition of EU at concentrations of 10 and 20 μM decreased (P < 0.05) the calreticulin (CALR) levels in expanded blastocysts when compared to the control treatment and EU-40 treatment. However, the EU-10 and EU-20 treatments had a greater (P < 0.05) mean total cell number (TCN) per expanded blastocyst when compared to the control treatment and EU-40 treatment. In conclusion, the addition of EU to the enriched culture medium during IVM of bovine oocytes improved the antioxidant capacity of the spent medium, as well as the cleavage rate and embryonic quality (i.e., TCN/expanded blastocyst), and reduced the endoplasmic reticulum stress (i.e., CALR levels) in the embryos. Thus, we recommend enriching the IVM medium with 10 μM EU for in vitro bovine embryo production.