Asiatic acid reduces lipopolysaccharides-induced pulp inflammation through activation of nuclear factor erythroid 2-related factor 2 in rats.

Background: Dental pulp inflammation, often initiated by Gram-negative microorganisms and lipopolysaccharides (LPS), can lead to pulpitis and, subsequently, dental pulp necrosis, compromising tooth structure and increasing susceptibility to fracture. Asiatic acid, derived from Centella asiatica, has demonstrated pharmacological properties, including anti-inflammatory and antioxidant effects, making it a potential candidate for mitigating LPS-induced pulp inflammation. This in vivo study aims to investigate the impact of Asiatic acid on the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in Rattus norvegicus with LPS-induced pulp inflammation. Methods: This quasi-laboratory experimental in vivo study employed a post-test-only control group design to investigate the effects of Asiatic acid on LPS-induced pulp inflammation in Wistar rats. Thirty rats were randomly divided into six groups subjected to various interventions. LPS was administered to all groups for 6 h except the standard control group (CG, n = 5). The negative control group (NCG, n = 5) received only glass ionomer cement. The positive control group (PCG, n = 5) received Eugenol with glass ionomer cement. Intervention groups 1, 2, and 3 (IG1, IG2, IG3; n = 5 each) received Asiatic acid at concentrations of 0.5%, 1%, and 2%, respectively, with glass ionomer cement. Dental pulp inflammation was confirmed through immunological (tumor necrosis factor alpha (TNF-α) levels), histopathological (inflammatory parameters), and physiological (pain assessment using the rat grimace scale) analyses. Additionally, Nrf2 levels were examined using enzyme-linked immunosorbent assay (ELISA). Results: Asiatic acid administration significantly influenced Nrf2 levels in rats with LPS-induced pulp inflammation. Nrf2 levels were significantly higher in groups treated with 0.5% (IG1) (8.810 ± 1.092 ng/mL; p = 0.047), 1.0% (IG2) (9.132 ± 1.285 ng/mL; p = 0.020), and 2.0% (IG3) (11.972 ± 1.888 ng/mL; p = 0.000) Asiatic acid compared to NCG (7.146 ± 0.706). Notably, Nrf2 levels were also significantly higher in the 2.0% Asiatic acid group (IG3) compared to the PCG treated with Eugenol (8.846 ± 0.888 ng/mL; p = 0.001), as well as IG1 (p = 0.001) and IG2 (p = 0.002). However, no significant difference was observed between administering 0.5% Asiatic acid (IG1), 1.0% Asiatic acid (IG2), and Eugenol (PCG). Conclusion: This research showed that Asiatic acid significantly impacted the Nrf2 levels in rats with LPS-induced pulp inflammation. This suggests that it has the potential to be used as a therapeutic agent for reducing dental pulp inflammation. These findings support the need to further explore Asiatic acid as a promising intervention for maintaining dental pulp health.

Eugenol's electrochemical behavior, complexation interaction with copper chloride, antioxidant activity, and potential drug molecular docking application for Covid-19.

Electrochemical studies were conducted to analyze the behavior of eugenol, CuCl2, and their complex using cyclic voltammetry. The oxidation mechanisms of eugenol and the redox behavior of copper ions were elucidated, showing differences in reversibility and charge transfer coefficients. Various kinetic and solvation parameters were determined. The redox behavior of CuCl2 was found to be more reversible compared to the copper-eugenol complex. The copper-eugenol complex exhibited enhanced antioxidant activity compared to eugenol and standard ascorbic acid. The eugenol was oxidized to form eugenol quinone methide through two postulated irreversible mechanisms. Molecular docking studies suggested higher potential bioactivity of the copper-eugenol complex towards the target protein of COVID-19 than the eugenol ligand.

Comparative Evaluation of the Quality of Obturation Between Three Obturation Techniques in Primary Canines: An In Vitro Study.

Aims This study compares three obturation techniques (rotary lentulo spiral, handheld lentulo spiral, and pressure syringe) for the quality of two filling pastes (zinc oxide eugenol (ZOE) paste and Metapex (Meta Biomed Co., Ltd., Chungcheongbuk-do, Korea). Methods and materials Sixty extracted primary canines were instrumented and obturated by filling materials. The obturation techniques were divided into three groups according to different obturation techniques. Obturation quality was evaluated for length, density, and presence of voids by using digital radiography. Results This study showed that the handheld lentulo spiral technique using Metapex and ZOE exhibited more optimal fillings for obturation length. The highest density obturation was achieved using the syringe injection approach with Metapex and ZOE. The highest incidence of both external and internal voids was observed in the group using ZOE with the handheld lentulo spiral technique Conclusions Based on the findings of this study, for both filling materials, the handheld lentulo spiral technique had the greatest number of optimal lengths but there were also more voids.

Design, synthesis, docking studies and bioactivity evaluation of 1,2,3-triazole eugenol derivatives.

Aim: The design, synthesis, docking studies and evaluation of the in vitro antifungal and cytotoxic properties of eugenol (EUG) containing 1,2,3-triazole derivatives are reported. Most of the derivatives have not been reported.Materials & methods: The EUG derivatives were synthesized, molecular docked and tested for their antifungal activity.Results: The compounds showed potent antifungal activity against Trichophyton rubrum, associated with dermatophytosis. Compounds 2a and 2i exhibited promising results, with 2a being four-times more potent than EUG. The binding mode prediction was similar to itraconazole in the lanosterol-14-α-demethylase wild-type and G73E mutant binding sites. Additionally, the pharmacokinetic profile prediction suggests good gastrointestinal absorption and potential oral administration.Conclusion: Compound 2a is a promising antifungal agent against dermatophytosis caused by T. rubrum.

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Effects of Chitosan as a Novel Obturation Material for Pulpectomized Teeth on Periapical Inflammation, Periodontal Ligament Widening, and Hard Tissue Resorption: A Preliminary Exploratory Study on Dogs.

Objectives: This preliminary animal study was conducted to assess the effects of chitosan as a novel obturation material for pulpectomized teeth on periapical inflammation, periodontal ligament (PDL) widening, and hard tissue resorption. Materials and Methods: Forty premolar root canals in two mature dogs were obturated with zinc oxide eugenol (ZOE) and an experimental 3% chitosan paste (n=20 in each group). The teeth were then restored with amalgam. After 28 days, the dogs were sacrificed, and histopathological assessment was performed. The amount of resorbed obturation material, degree of inflammatory response, degree of PDL widening, and the number of bone/cementum/dentin resorption defects were recorded under ×40 and ×200 magnifications. Data were analyzed using the Mann-Whitney U test, one-sample Wilcoxon signed-rank test, and Fisher's exact test (α=0.05). Results: Bone, cementum, and dentin resorption were seen in 6, 10, and 1 chitosan-obturated canals and 14, 15, and 0 ZOE-obturated canals, respectively. Only the bone resorption defects were significantly fewer in the chitosan group (P=0.026). Mild, moderate, and severe inflammation were observed in 17, 3, and 0 chitosan-obturated canals, and 7, 9, and 4 ZOE-filled canals, respectively (P=0.004). Mild, moderate, and severe PDL widening were seen around 15, 5, and 0 chitosan-filled canals and 7, 12, and 1 ZOE-filled canals, respectively (P=0.025). Conclusion: The 3% chitosan was superior to ZOE in terms of causing less inflammation and PDL widening. It also decreased bone resorption and acted similar to ZOE in terms of dentin and cementum resorption.

Evaluation of the Effectiveness of Eugenol and MS-222 as Anesthetics in Zebrafish in Repeated Exposures and Post-Anesthesia Behaviour.

The increasing use of the zebrafish (Danio rerio) in scientific experiments has made it necessary to implement anesthesia protocols guaranteeing minimum pain and suffering for these animals and ensuring the reliability of the results obtained from their research. Therefore, we aimed to compare the effectiveness of two anesthetics, eugenol and MS-222, in consecutive administrations and evaluate the zebrafish behaviour after repeated anesthesia. Thus, several zebrafish were anaesthetized with eugenol, MS-222, and buffered MS-222 three times repeatedly with a 24-h interval between each exposure. The induction and recovery periods were also timed. Their swimming frequency was determined after each exposure to assess their behaviour after the anesthesia. Anesthesia induction was quicker with eugenol compared to MS-222. However, eugenol presented longer recovery times, which were prolonged after each exposure. Also, the swimming frequency was reduced after each anesthesia with eugenol. The buffered version of MS-222 was more efficacious than the non-buffered one. Both versions of MS-222 did not affect the swimming frequency. Based on these findings, we recommend the utilization of MS-222 buffered rather than eugenol when repeated, brief-duration anesthesia is necessitated for a study.

Eugenol: A Potential Modulator of Human Platelet Activation and Mouse Mesenteric Vascular Thrombosis via an Innovative cPLA2-NF-κB Signaling Axis.

BACKGROUND: Platelets, a type of anucleated cell, play a crucial role in cardiovascular diseases (CVDs). Therefore, targeting platelet activation is essential for mitigating CVDs. Endogenous agonists, such as collagen, activate platelets by initiating signal transduction through specific platelet receptors, leading to platelet aggregation. Eugenol, primarily sourced from clove oil, is known for its antibacterial, anticancer, and anti-inflammatory properties, making it a valuable medicinal agent. In our previous study, eugenol was shown to inhibit platelet aggregation induced by collagen and arachidonic acid. We concluded that eugenol exerts a potent inhibitory effect on platelet activation by targeting the PLCγ2-PKC and cPLA2-TxA2 pathways, thereby suppressing platelet aggregation. In our current study, we found that eugenol significantly inhibits NF-κB activation. This led us to investigate the relationship between the NF-κB and cPLA2 pathways to elucidate how eugenol suppresses platelet activation. METHODS: In this study, we prepared platelet suspensions from the blood of healthy human donors to evaluate the inhibitory mechanisms of eugenol on platelet activation. We utilized immunoblotting and confocal microscopy to analyze these mechanisms in detail. Additionally, we assessed the anti-thrombotic effect of eugenol by observing fluorescein-induced platelet plug formation in the mesenteric microvessels of mice. RESULTS: For immunoblotting and confocal microscopy studies, eugenol significantly inhibited NF-κB-mediated signaling events stimulated by collagen in human platelets. Specifically, it reduced the phosphorylation of IKK and p65 and prevented the degradation of IκBα. Additionally, CAY10502, a cPLA2 inhibitor, significantly reduced NF-κB-mediated signaling events. In contrast, BAY11-7082, an IKK inhibitor, did not affect collagen-stimulated cPLA2 phosphorylation. These findings suggest that cPLA2 acts as an upstream regulator of NF-κB activation during platelet activation. Furthermore, both BAY11-7082 and CAY10502 significantly reduced the collagen-induced rise in intracellular calcium levels. In the animal study, eugenol demonstrated potential as an anti-thrombotic agent by significantly reducing platelet plug formation in fluorescein-irradiated mouse mesenteric microvessels. CONCLUSION: Our study uncovered a novel pathway in platelet activation involving the cPLA2-NF-κB axis, which plays a key role in the antiplatelet effects of eugenol. These findings suggest that eugenol could serve as a valuable and potent prophylactic or therapeutic option for arterial thrombosis.

Impact of eugenol on biofilm development in Shigella flexneri 1457: a plant terpenoid based-approach to inhibit food-borne pathogen.

Shigella flexneri is a gram-negative bacterium responsible for shigellosis and bacterial dysentery. Despite using various synthetic antimicrobial agents and antibiotics, their efficacy is limited, prompting concerns over antibiotic resistance and associated health risks. This study investigated eugenol, a polyphenol with inherent antioxidant and antibacterial properties, as a potential alternative treatment. We aimed to evaluate eugenol's antibacterial effects and mechanisms of action against S. flexneri and its impact on biofilm formation. We observed significant growth suppression of S. flexneri with eugenol concentrations of 8-10 mM (98.29%). Quantitative analysis using the Crystal Violet assay demonstrated a marked reduction in biofilm formation at 10 mM (97.01 %). Assessment of Cell Viability and morphology via Fluorescence-Activated Cell Sorting and Scanning Electron Microscopy confirmed these findings. Additionally, qPCR analysis revealed the downregulation of key genes responsible for adhesion (yebL), quorum sensing (rcsC, sdiA), and EPS production (s0482) associated with bacterial growth and biofilm formation. The present study suggests eugenol could offer a promising alternative to conventional antibiotics for treating shigellosis caused by S. flexneri.

Revealing the interaction between alpha-chymotrypsin and eugenol: An integrated multi-spectral and dynamic simulation approach.

The study aims to explore the effects of Eugenol (EUG) as an antioxidant on α-Chymotrypsin (α-Chy) and its interaction mechanism, with potential implications for new therapy development. The interaction between EUG and α-Chy was demonstrated through ultraviolet (UV) spectroscopy, which resulted in a shift in absorption with docking energies of -22.76 kJ/mol. An increase in fluorescence intensity indicated that the Trp residues moved to a less polar environment, which is consistent with the changes in accessible surface area (ASA) values. The presence of EUG led to a decrease in α-helix, ß-turn, and random coil structures as shown by circular dichroism (CD) and Fourier-transform infrared (FTIR) analysis. Additionally, there was a slight increase in ß-sheet structures, indicating a decrease in enzyme stability. However, tests for thermal stability showed a decrease in folding upon the introduction of EUG, which contradicted the results obtained from molecular dynamics (MD) simulations. The docking studies revealed that EUG forms hydrogen bonds and van der Waals forces with the enzyme, indicating the interaction mechanism. Kinetic studies confirmed that EUG acts as a mixed inhibitor. However, further research involving live organisms is necessary to fully understand its potential.

Role of phosphorylation and vanilloid ligand structure in ligand-dependent differential activations of transient receptor potential vanilloid 1.

Vanilloid analogs, which can activate transient receptor potential vanilloid 1 (TRPV1), have been classified into two types based on susceptibility to forskolin (FSK). Treatment of cells expressing TRPV1 with FSK enhances TRPV1 responses to capsaicin-type ligands while diminishing the responses to eugenol-type ligands. In this study, we determined the effect of FSK on the activation of TRPV1 stimulated with vanilloid ligands, through the influx of Ca2+ in HEK293T cells expressing TRPV1. Our findings suggest that the effects of FSK can be attributed to the phosphorylation of TRPV1, as evidenced by using a protein kinase A (PKA) inhibitor and TRPV1 mutants at potential phosphorylation sites. Furthermore, we examined the structure-activity relationship of 13 vanilloid analogs. Our results indicated that vanilloid compounds could be classified into three types, i.e., the previously reported two types and a novel type of 10-shogaol, by which TRPV1 activation was insusceptible to the FSK treatment.

Ameliorative action of eugenol on nitrate induced reproductive toxicity in male rats.

There is a great concern for studies to prevent nitrate (NO3) induced male reproductive toxicity as it might lead to infertility. Therefore, the study was aimed to investigate the ameliorative effects of eugenol on NO3 induced male reproductive toxicity in wistar rats. Adult male rats were randomly divided into five groups (n=5). The first group was served as control, the second and third group of rats were treated with 100 mg/kg bw of sodium nitrate (NaNO3) and NO3 contaminated ground water respectively. The fourth and fifth group of rats were orally intubated with eugenol (100 mg/kg bw) and then exposed to NaNO3 and NO3 contaminated ground water respectively. The treatment was continued for 52 days. Nitrate exposure significantly decreased the sperm motility, testicular 3-beta-hydroxysteroid dehydrogenase activity, serum concentration of testosterone, activities of superoxide dismutase and catalase in testis and spermatozoa and different categories of germ cells in stage VII of spermatogenesis. Further, there was significant increase in sperm abnormality and levels of nitrite (NO2) and malondialdehyde in testis and spermatozoa of NO3 treated rats. In addition, NO3 exposure distorted the histological architecture of seminiferous tubules of testis. It was established that NO3 induced high production of NO2 affected spermatogenesis, steroidogenesis and sperm motility. However, in the present study, pretreatment of eugenol prevented NO3 induced reproductive alterations by decreasing the level of NO2. These findings clearly showed the protective action of eugenol against NO3 induced oxidative stress in male reproductive system.

New Perspectives about Relevant Natural Compounds for Current Dentistry Research.

Natural compounds have been used since the earliest civilizations and remain, to this day, a safer alternative for treating various dental problems. These present antimicrobial, anti-inflammatory, antioxidant, analgesic, and antimutagenic effects, making them useful in the prophylactic and curative treatment of various oral diseases such as infections, gingivitis, periodontitis, and even cancer. Due to the high incidence of unpleasant adverse reactions to synthetic compounds, natural products tend to gradually replace conventional treatment, as they can be just as potent and cause fewer, milder adverse effects. Researchers use several methods to measure the effectiveness and safety profile of these compounds, and employing standard techniques also contributes to progress across all medical disciplines.

Biocompatibility and Antibacterial Activity of Eugenol and Copaiba Essential Oil-Based Emulsions Loaded on Cotton Textile Materials.

The present study was focused on the preparation, characterization and application onto cotton fabrics of different topical oil-in-water emulsions based on chitosan, eugenol and copaiba essential oil for potential topical applications. Different amounts of copaiba essential oil (oil phases) and eugenol were used, while the water phase consisted of hamamelis water. The designed formulations were evaluated via optical microscopy and rheological parameters assessment. The textile materials treated with the developed emulsions were analyzed in terms of antibacterial efficiency and in vitro and in vivo biocompatibility. The rheological measurements have shown that the emulsions' stability was dependent on their viscosity and structure of the colloidal systems. The emulsions remained stable at temperatures equal to or below 35 °C, but an increase in temperature led to droplet flocculation and creaming. The emulsion-treated textiles exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus, and in vivo biocompatibility on the skin of guinea pigs without sensitization effects. Our study revealed that eugenol and copaiba essential oil-based emulsions loaded on cotton textile materials could be promising candidates for developing skin-friendly textiles designed for different topical applications.

Clinical and Radiographic Evaluation of Zinc Oxide Eugenol, Zinc Oxide Powder with Aloe Vera Gel, and Endoflas Powder with Aloe Vera Gel as an Obturating Material in Primary Molars: An In Vivo Study.

Aim: The present study was conducted to compare three obturating materials-zinc oxide eugenol (ZOE), zinc oxide (ZO) powder with aloe vera gel, and Endoflas powder with aloe vera gel in primary molars. Materials and methods: The study was conducted on 45 primary molars with chronic infection. A total of 45 primary molars were divided into three groups of 15 each. Group I was obturated with ZOE paste, group II was obturated with ZO powder and aloe vera gel, and group III was obturated with Endoflas powder with aloe vera gel. Clinical and radiographic success and failure at 3, 6, and 9 months were evaluated. Results: A total of 15 molars in group I, 15 molars in group II, and 14 molars in group III showed clinical and radiographic success at the 9th-month follow-up. However, there was only one failure in group III during the 9th-month follow-up. Conclusion: It was concluded that all three groups showed promising results; ZOE is still considered standard material, whereas ZO powder with aloe vera gel can be used as an alternative to ZOE. Endoflas with aloe vera gel can also be used as an obturating material. How to cite this article: Mohile S, Sharma N, Asopa K, et al. Clinical and Radiographic Evaluation of Zinc Oxide Eugenol, Zinc Oxide Powder with Aloe Vera Gel, and Endoflas Powder with Aloe Vera Gel as an Obturating Material in Primary Molars: An In Vivo Study. Int J Clin Pediatr Dent 2024;17(2):168-172.

The vasodilator effect of Eugenol on uterine artery - potential therapeutic applications in pregnancy-associated hypertension.

Preeclampsia, a gestational associated hypertension, has been reported in 6-8% of pregnant women worldwide leading to premature delivery and low birth weight of newborn due to reduced blood flow to placenta. Although several vasodilators (Methyl dopa, hydralazine, ß-blockers and diuretics) are currently in use to treat preeclampsia, still there is a search for safer drugs with better efficacy. Lately, antihypertensive vasodilators from natural sources are gaining importance in treating preeclampsia. Eugenol (Eug), a natural essential oil, has been traditionally used in health and food products without any risk. In the present study, ex vivo experiments were designed to examine the vasorelaxation effect of Eug and its signaling pathways in a middle uterine artery (MUA) of pregnant Capra hircus (Ch). In presence of different blockers (L-NAME, indomethacin, ODQ, Ouabain, glibenclamide, 4-AP, Ba2, Carbenoxolone and 18ß Glycyrrhetinic acid), Eug-induced concentration-dependent vasorelaxation response was elicited. The results showed that Eug caused a greater vasorelaxation effect in the MU of pregnant animals, which is mediated by potential activation of eNOS, KATP channels, and Kir channels with moderate activation of Na+- K+- ATPase and sGC and MEGJ. These findings provide a strong basis for developing Eug as a therapeutic candidate in the treatment of pregnancy-associated hypertension.

Effect of Rheum ribes L. pulp enriched with eugenol or thymol on survival of foodborne pathogens and quality parameters of chicken breast fillets.

The aim of this study was to characterize the pulp of Rheum ribes L. and to determine the effect of the pulp enriched with eugenol (1 %) or thymol (1 %) on the microbiological and physico-chemical quality of chicken breast fillets. Chicken breast fillets, inoculated with Listeria monocytogenes, Salmonella enterica subsp. enterica serovar Typhimurium, and Escherichia coli O157:H7 (~6.0 log10), were marinated for 24 h in a mixture prepared from a combination of Rheum ribes L. pulp with eugenol or thymol. The quality parameters were analyzed for 15 days at +4 °C. The Rheum ribes L. pulp was found to have high antioxidant activity, high total phenolic content and contained 22 different phenolic substances, among which rutin ranked first. The pulp contained high levels of p-xylene and o-xylene as volatile substances and citric acid as an organic acid. The combination of Pulp + Eugenol + Thymol (PET) reduced the number of pathogens in chicken breast fillets by 2.03 to 3.50 log10 on day 0 and by 2.25 to 4.21 log10 on day 15, compared to the control group (P < 0.05). The marinating treatment significantly lowered the pH values of fillet samples on the first day of the study, compared to the control group (P < 0.05). During storage, TVB-N levels showed slower increase in the treatment groups compared to the control group (P < 0.05). In addition, the marinating process led to significant changes in physicochemical parameters such as water holding capacity, color, texture, cooking loss, and drip loss compared to the control group (P < 0.05). In conclusion, the results of this study showed that the pulp of Rheum ribes L., which has a high antioxidant capacity and contains various bioactive compounds. Furthermore, S. Typhimurium, E. coli O157:H7 and L. monocytogenes were inhibited considerably by marinating Rheum ribes L. pulp with a combination of eugenol and thymol.

Ocimum sanctum as a Source of Quorum Sensing Inhibitors to Combat Antibiotic Resistance of Human and Aquaculture Pathogens.

Biofilms play a decisive role in the infectious process and the development of antibiotic resistance. The establishment of bacterial biofilms is regulated by a signal-mediated cell-cell communication process called "quorum sensing" (QS). The identification of quorum sensing inhibitors (QSI) to mitigate the QS process may facilitate the development of novel treatment strategies for biofilm-based infections. In this study, the traditional medicinal plant Ocimum sanctum was screened for QS inhibitory potential. Sub-MICs of the extract significantly affected the secretion of EPS in Gram-negative human pathogens such as Escherichia coli, Pseudomonas aeruginosa PAO1, Proteus mirabilis, and Serratia marcescens, as well as aquaculture pathogens Vibrio harveyi, V. parahaemolyticus, and V. vulnificus, which render the bacteria more sensitive, leading to a loss of bacterial biomass from the substratum. The observed inhibitory activity of the O. sanctum extract might be attributed to the presence of eugenol, as evidenced through ultraviolet (UV)-visible, gas chromatography-mass spectroscopy (GC-MS), Fourier transformer infrared (FTIR) spectroscopy analyses, and computational studies. Additionally, the QSI potential of eugenol was corroborated through in vitro studies using the marker strain Chromobacterium violaceum.

Suppression of essential oil biosynthesis in sweet basil cotyledons under hypergravity conditions.

The mechanism through which gravity influences the biosynthesis of essential oils in herbs is an important issue for plant and space biology. Sweet basil (Ocimum basilicum L.) seedlings were cultivated under centrifugal hypergravity conditions at 100 g in the light, and the growth of cotyledons, development of glandular hairs, and biosynthesis of essential oils were analyzed. The area and fresh weight of the cotyledons increased by similar amounts irrespective of the gravitational conditions. On the abaxial surface of the cotyledons, glandular hairs, where essential oils are synthesized and stored, developed from those with single-cell heads to those with four-cell heads; however, hypergravity did not affect this development. The main components, methyl eugenol and 1,8-cineole, in the essential oils of cotyledons were lower in cotyledons grown under hypergravity conditions. The gene expression of enzymes in the phenylpropanoid pathway involved in the synthesis of methyl eugenol, such as phenylalanine ammonia lyase (PAL) and eugenol O-methyltransferase (EOMT), was downregulated by hypergravity. Hypergravity also decreased the gene expression of enzymes in the 2C-methyl-d-erythritol 4-phosphate (MEP) pathway involved in the synthesis of 1,8-cineole, such as 1-deoxy-d-xylulose-5-phosphate synthase (DXS) and 1,8-cineole synthase (CINS). These results indicate that hypergravity without affecting the development of glandular hairs, decreases the expression of genes related to the biosynthesis of methyl eugenol and 1,8-cineole, which may cause a decrease in the amounts of both essential oils in sweet basil cotyledons.

In vitro antiviral activity of eugenol on Singapore grouper iridovirus.

The high mortality rate of Singapore grouper iridovirus (SGIV) posing a serious threat to the grouper aquaculture industry and causing significant economic losses. Therefore, finding effective drugs against SGIV is of great significance. Eugenol (C10H12O2) is a phenolic aromatic compound, has been widely studied for its anti-inflammatory, antioxidant and antiviral capacity. In this study, we explored the effect of eugenol on SGIV infection and its possible mechanisms using grouper spleen cells (GS) as an in vitro model. We found that treatment of GS cells with 100 µM eugenol for 4 h exhibited the optimal inhibitory effect on SGIV. Eugenol was able to reduce the expression level of inflammatory factors by inhibiting the activation of MAPK pathway and also inhibited the activity of NF-κB and AP-1 promoter. On the other hand, eugenol attenuated cellular oxidative stress by reducing intracellular ROS and promoted the expression of interferon-related genes. Therefore, we conclude that eugenol inhibits SGIV infection by enhancing cellular immunity through its anti-inflammatory and antioxidant functions.

The Antibacterial Properties of a Reinforced Zinc Oxide Eugenol Combined with Cloisite 5A Nanoclay: An In-Vitro Study.

Pulpotomies and pulpectomies are the most common clinical approach for dental caries in the primary dentition. Reinforced zinc oxide eugenol (ZOE) is an ideal material for filling in the pulp chamber after pulp therapies. The aim of this study was to assess the addition of Cloisite 5A nanoclay material to ZOE and evaluate its antibacterial properties. In this case-control study, the nanoclay nanoparticles were dissolved using a solvent (Eugenol) in different concentrations and their antibacterial properties were assessed using the agar diffusion test and biofilm analysis of Streptococcus mutans (S. mutans), Enterococcus faecalis (E. faecalis), and Escherichia coli (E. coli) in in vitro conditions using the AATCC 100 standards. The diameter of the inhibition zone was measured and assessed statistically using the SPSS software (Version 28, IBM, Chicago, IL, USA) with a significance level of 0.05. The antibacterial properties of the ZOE with nanoclay particles were significantly greater in comparison to the plain ZOE against E. faecalis, S. mutans, and E. coli. The inhibition zone against E. coli under the effect of the ZOE and nanoclay particles combined was significantly higher than that against E. faecalis and S. mutans. The current study showed that the addition of Cloisite 5A nanoclay particles can improve the antibacterial properties of ZOE significantly at certain concentrations.