• Journal of Pharmacopuncture
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• v.25 no.1
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• pp.37-45
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• 2022

Objectives: The quorum-sensing-inhibitory and anti-biofilm activities of the methanol extract of E. globulus leaves were determined against clinically isolated multidrug-resistant Pseudomonas aeruginosa. Methods: The preliminary anti-quorum-sensing (AQS) activity of eucalyptus was investigated against a biosensor strain Chromobacterium violaceum ATCC 12472 (CV12472) by using the agar well diffusion method. The effect of sub-minimum inhibitory concentrations (sub-MICs) of the methanol extract of eucalyptus on different quorum-sensing-regulated virulence factors, such as swarming motility, pyocyanin pigment, exopolysaccharide (EPS), and biofilm formation, against clinical isolates (CIs 2, 3, and 4) and reference PA01 of Pseudomonas aeruginosa were determined using the swarm diameter (mm)-measurement method, chloroform extraction method, phenol (5%)-sulphuric acid (concentrated) method, and the microtiter plate assay respectively, and the inhibition (%) in formation were calculated. Results: The preliminary AQS activity (violacein pigment inhibition) of eucalyptus was confirmed against Chromobacterium violaceum ATCC 12472 (CV12472). The eucalyptus extract also showed concentration-dependent inhibition (%) of swarming motility, pyocyanin pigment, EPS, and biofilm formation in different CIs and PA01 of P. aeruginosa. Conclusion: Our results revealed the effectiveness of the E. globulus extract for the regulation of quorum-sensing-dependent virulence factors and biofilm formation at a reduced dose (sub-MICs) and suggest that E. globulus may be a therapeutic agent for curing and controlling bacterial infection and thereby reducing the possibility of resistance development in pathogenic strains.

• Natural Product Sciences
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• v.14 no.1
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• pp.27-31
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• 2008

We have evaluated the combined antifungal effects of the essential oil from Eucalyptus globulus or its main component 1,8-cineole with ketoconazole. Checkerboard microtiter tests were used to analyze their effects against three Candida and six Trichophyton species. The susceptibility of the Trichophyton species to E. globulus essential oil differed distinctly. The fractional inhibitory concentration indices (FICIs) against the tested Candida species ranged between 0.09 and 0.38 for ketoconazole combined with E. globulus essential oil or 1,8-cineole, indicating significant synergism between ketoconazole and the oil samples. Similar experiments using Trichophyton species resulted in FICIs between 0.28 and 0.63, indicating relatively weaker combined effects than those observed with Candida species. Thus, the data reported here show that the anti-Candida effects of ketoconazole can be significantly improved in the presence of E. globulus essential oil or 1, 8-cineole.

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.557-566
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• 2019

Radial and tangential water diffusion in Eucalyptus globulus wood was investigated using three mature trees from a forest in Khemis Sahel (North Morocco). Absorption and desorption kinetics experiments were conducted at ambient temperature ($25^{\circ}C$) and $30^{\circ}C$, respectively, and a relative humidity of 60%. The diffusion coefficients in the two directions were determined under imposed hygrothermal conditions; they were greater in the radial direction for the absorption as well as desorption processes. Convective drying under load, preceded by reconditioning and followed up by balancing, revealed the drying conditions that corresponded to the appropriate drying schedules for E. globulus wood. This was verified by measuring the cracks and bowsbefore and after drying of boards.

• Archives of Pharmacal Research
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• v.23 no.2
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• pp.147-150
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• 2000

Twelve compounds with lipid peroxidation inhibitory activity were isolated from the stem bark of E. globulus. Their structures were assigned as a new aromatic monoterpene (1) and eleven known compounds, pinoresinol (2), vomifoliol (3), 3,4,5-trimethoxyphenol 1-O-$\beta$-D-(6'-O-galloyl)glucopyranoside (4), methyl gallate (5), rhamnazin (6), rhamnetin (7), eriodictyol (8), quercetin (9), taxifolin (10), engelitin (11), and catechin (12) on the basis of UV, mass, and NMR spectroscopic analyses. These compounds except vomifoliol significantly inhibited lipid peroxidation in rat liver microsome.

• Korean Journal of Pharmacognosy
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• v.29 no.3
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• pp.163-168
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• 1998

Seven antioxidative compounds were isolated from chloroform and ethyl acetate extracts of the stem bark of Eucalyptus globulus (Myrtaceae). They were identified as rhamnazin (1), rhamnetin (2), naringenin (3), eriodictyol (4), quercetin (5), taxifolin (6) and dihydrokaempferol-3-rhamnoside (7) on the basis of various spectroscopic analyses. These compounds inhibited lipid peroxidation with $IC_{50}$ values of 0.08-30 ${\mu}g/ml$.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.40-48
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• 2004

Background and Objectives: Aroma therapy using Eucalyptus Globulus essential oil for curing allergic rhinitis is an inhalation treatment which has been applied as an aid to oriental clinics which use a fundamental treatment such as acupuncture and herbs. There have been no studies so far performed on the effect of this oils' use, only . We aimed to find out the therapeutic effect of its exclusive use only on an Animal Model with Allergic Rhinitis. Materials and Methods: Sprague-Dawley rats were induced the allergic rhinitis by ovalbumin solution. And then, rats in the treated group were treated by diffusing Eucalyptus essential oil in a flask for 7 days. Compared with the treated group, rats in the control group were treated by diffusing normal saline in a flask for 7 days. We observed changes in glandular cells and mast cells in nasal mucosa and submucosa; also changes in the number of eosinophils and neutrophils in blood and the succus of rhinenchysis. Results: The number of neutrophils in the succus of rhinenchysis was significantly decreased in treated group compared with control group(p<0.05). The number of neutrophils in blood and mast cells in nasal mucosa were decreased in the treated group but, these were not significant statistically(p>0.05). Histologic changes showed edema; congestion and expansion of grandular cells in nasal submucosa and hypertrophy of epithelium in nasal mucosa were decreased in treated group compared with control group. Conclusions: The results may suggest that the inhalation treatment using Eucalyptus essential oil decreases the inflammatory response on an Animal Model with Allergic Rhinitis.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.421-427
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• 2016

Acne is known as the most common skin disease. It commonly occurs during adolescents, but it is also present in children and adults because of air pollution, drug abuse and so on. In addition to the hormonal, genetic and environmental factors, Propionibacterium acnes (P. acnes) have also critical roles in outbreak of acne by inducing inflammatory mediators. Increase of sebum production provides an ideal environment for P. acnes that induce inflammation on the skin by activation of monocytic cells and stimulation of inflammatory cytokines. In this study, natural extracts were investigated for anti-inflammatory effects against inflammatory acne by P. acnes infection in terms of reducing cytokine production. Eucalyptus globulus extracts effectively suppressed mRNA synthesis of inflammatory mediators such as $TNF-{\alpha}$, $IL-1{\beta}$, IL-2, and NLRP3 in P. acnes-activated macrophages. Moreover, Eucalyptus globulus extracts inhibit activation of transcription factors, $NF-{\kappa}B$ and NFAT, which are known as key regulators of inflammatory cytokine production. This study suggests the potential of using Eucalyptus globulus extracts as alternative agents for the treatment of acne.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.82-85
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• 2000

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.46-51
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• 2019

This study was carried out to evaluate antimicrobial effects of a mixture of resin fractionated ethanol extract of Eucalyptus globulus, Yucca recurvifolia, and tea tree (Melaleuca alternifolia). The plant fraction mixture showed low minimum inhibitory concentration (0.24~3.32 mg/ml) against several bacteria and yeast that usually used as the target skin microbes in a cosmetic industry, and it was more effective than antibiotics, triclosan and ampicillin. In a time-kill assay the plant fraction mixture reduced more than 92% of microbial populations during 4 h, and significantly increased leakage of nucleotides from all microorganisms tested. Antimicrobial effect of the plant fraction mixture was not affected by divalent cation ($Mg^{2+}$ and $Ca^{2+}$). These results suggest that the fraction mixture of ethanol extracts of E. globulus, Y. recurvifolia, and M. alternifolia may be utilized as an efficient preservative in cosmetics to prevent contamination by human skin microbes.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.2
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• pp.103-108
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• 2006

Efficacy of aqueous leaf extracts of medicinal plants viz., Eucalyptus globulus, Ocimum sanctum and Piper betle were evaluated against the hatching of eggs, mortality of nymphs and mortality and fecundity of adult mealy bugs (Maconellicoccus hirsutus Green) under in vitro conditions. Totally seven concentrations 1, 5, 10, 20, 50, 70 and 100 percent were tested against mealy bugs. The results revealed that with the increase in the concentration of extracts, there was a corresponding decrease in hatching, nymphal & adult mortality and fecundity in all the extracts tested. The hatching of eggs was minimum at 100 percent concentration in E. globulus (20.00%) followed by O. sanctum (30.42%) and P. betle (36.06%) over control (96.73%). The growth and development of nymphs and adults were adversely affected after the treatment. The nymphs did not attain the adult stage and there was total mortality of nymphs in different treatments. The duration of nymphal stage was reduced by 2-10 days in E. globulus, 1-7 days in O. sanctum and 1-2days P. betle at higher concentrations. However, at lower concentrations it was prolonged by 2-4 days in all the three extracts. At lower concentrations the mortality of adults was on par with the control. Similarly the adult duration was also reduced by 3-4 days at 100 percent concentration and prolonged by 5-6 days at lower concentrations in all the extracts. With the increase in concentrations of the extracts there was decrease in the fecundity of eggs. Thus, the leaf extracts of E. globulus was found to be most effective followed by O. sanctum and P. betle against mealy bugs.