Activity Of Cinnamon Essential Oils Research Articles

Antibacterial activity of cinnamon essential oil and its main component of cinnamaldehyde and the underlying mechanism.

Background: Plant essential oils have long been regarded as repositories of antimicrobial agents. In recent years, they have emerged as potential alternatives or supplements to antimicrobial drugs. Although literature reviews and previous studies have indicated that cinnamon essential oil (CIEO) and its major component, cinnamaldehyde (CID), possess potent antibacterial activities, their antibacterial mechanisms, especially the in vivo antibacterial mechanisms, remain elusive. Methods: In this study, we utilized the in vivo assessment system of Caenorhabditis elegans (C. elegans) to investigate the effects and mechanisms of high dose (100mg/L) and low dose (10mg/L) CIEO and CID in inhibiting Pseudomonas aeruginosa (P. aeruginosa). In addition, we also examined the in vitro antibacterial abilities of CIEO and CID against other common pathogens including P. aeruginosa and 4 other strains. Results: Our research revealed that both high (100mg/L) and low doses (10mg/L) of CIEO and CID treatment significantly alleviated the reduction in locomotion behavior, lifespan, and accumulation of P. aeruginosa in C. elegans infected with the bacteria. During P. aeruginosa infection, the transcriptional expression of antimicrobial peptide-related genes (lys-1 and lys-8) in C. elegans was upregulated with low-dose CIEO and CID treatment, while this trend was suppressed at high doses. Further investigation suggested that the PMK-1 mediated p38 signaling pathway may be involved in the regulation of CIEO and CID during nematode defense against P. aeruginosa infection. Furthermore, in vitro experimental results also revealed that CIEO and CID exhibit good antibacterial effects, which may be associated with their antioxidant properties. Conclusion: Our results indicated that low-dose CIEO and CID treatment could activate the p38 signaling pathway in C. elegans, thereby regulating antimicrobial peptides, and achieving antimicrobial effects. Meanwhile, high doses of CIEO and CID might directly participate in the internal antimicrobial processes of C. elegans. Our study provides research basis for the antibacterial properties of CIEO and CID both in vivo and in vitro.

Zein and tannic acid hybrid particles improving physical stability, controlled release properties, and antimicrobial activity of cinnamon essential oil loaded Pickering emulsions

Pickering emulsion loading essential oil has demonstrated a promising strategy as delivery system in food preservation, but localization in stability and antimicrobial activity limits application. In this study, Pickering emulsions co-loaded with tannic acid and cinnamon essential oil (ZTC) have been developed based on zein and tannic acid complexes (ZT) mediated interfacial engineering. Fourier transform infrared, fluorescence spectroscopy, and molecular docking results indicated tannic acid altered the structural of zein. Interfacial tension results indicated that tannic acid accelerated the adsorbed speed of zein particles by decreased interfacial tension (11.99–9.96 mN/m). ZT5 formed a viscoelastic and dense layer in oil–water interface than that for other ZTs, which improved stability and control release performance of ZTC. Furthermore, the ZTC showed an effective antimicrobial activity against spoilage organisms Pseudomonad paralactis MN10 and Lactobacillus sakei VMR17. These findings provide new insight for developing co-loaded multiple antimicrobial agents within Pickering emulsion as a delivery system.

Essential Oils of Mentha arvensis and Cinnamomum cassia Exhibit Distinct Antibacterial Activity at Different Temperatures In Vitro and on Chicken Skin.

The bacterial contamination of meat is a global concern, especially for the risk of Salmonella infection that can lead to health issues. Artificial antibacterial compounds used to preserve fresh meat can have negative health effects. We investigated the potential of natural essential oils (EOs), namely Mentha arvensis (mint) and Cinnamomum cassia (cinnamon) EOs, to prevent contamination of the food pathogen, Salmonella enterica subsp. enterica serotype Typhimurium, in vitro and on chicken skin. The gas chromatography-mass spectrometry (GC-MS) technique was used to determine the compositions of mint EO (MEO) and cinnamon EO (CEO); the most abundant compound in MEO was menthol (68.61%), and the most abundant compound was cinnamaldehyde (83.32%) in CEO. The antibacterial activity of MEO and CEO were examined in vapor and direct contact with S. typhimurium at temperatures of 4 °C, 25 °C, and 37 °C. The minimal inhibitory concentration at 37 °C for MEO and CEO reached 20.83 µL/mL, and the minimal bactericidal concentration of CEO was the same, while for MEO, it was two-fold higher. We report that in most tested conditions in experiments performed in vitro and on chicken skin, CEO exhibits a stronger antibacterial effect than MEO. In the vapor phase, MEO was more effective against S. typhimurium than CEO at 4 °C. In direct contact, the growth of S. typhimurium was inhibited more efficiently by MEO than CEO at small concentrations and a longer exposure time at 37 °C. The exploration of CEO and MEO employment for the inhibition of Salmonella bacteria at different temperatures and conditions expands the possibilities of developing more environment- and consumer-friendly antibacterial protection for raw meat.

Evaluation of the antibacterial activity of cinnamon essential oil and its individual compounds on Aggregatibacter actinomycetemcomitans isolated from black extrinsic tooth stain: an in vitro study.

Black extrinsic tooth stain (BETS) is a health challenge that commonly affects children. Aggregatibacter actinomycetemcomitans (Aa) presents in higher prevalence within the polymicrobial community of BETS. In this study, the anti-planktonic and anti-sessile activities of cinnamon essential oil (CEO) and its individual compounds against Aa were evaluated. The preventive effect of CEO and its active substances on BETS formation was also studied in vitro. Aa was isolated from a preschool child with BETS and was identified based on the morphological characteristics, MALDI-TOF mass spectroscopy and 16S rRNA sequencing. The effect of CEO and its individual compounds on the growth kinetics of planktonic and sessile Aa cells as well as their antibacterial efficacy and their rate of bacterial killing were examined. The preventive effect of CEO and its active substances on the formation of BETS was evaluated using an ex vivo model. The data were analysed using one-way analysis of variance (ANOVA) and the significance level was set at p < 0.05. Out of eight individual compounds of CEO, only eugenol, cinnamaldehyde and α-methyl cinnamaldehyde showed anti-Aa activities. The values of the minimum inhibitory concentrations (MICs) were in the following order: CEO (421.5mg/ml) > α-methyl cinnamaldehyde (26.37mg/ml) > cinnamaldehyde (0.209mg/ml) > eugenol (0.052mg/ml). CEO, eugenol, cinnamaldehyde and α-methyl cinnamaldehyde, respectively, exhibited two-, four-, four- and eightfold increase of sessile MIC compared to their planktonic MIC. The growth kinetics of both planktonic and sessile Aa in the presence of CEO, eugenol, cinnamaldehyde and α-methyl cinnamaldehyde revealed a complete inhibition at the MICs and 5.3%-37.4% biofilm inhibition at sub-MICs. The time-killing study demonstrated that CEO, eugenol and cinnamaldehyde were capable of reducing the survival rate of both planktonic and sessile Aa cells after 15-20 and 25-30min, respectively. However, α-methyl cinnamaldehyde showed a superior anti-planktonic to anti-biofilm activity. The daily incorporation of CEO, eugenol and cinnamaldehyde at their MICs for 14days totally prevented the formation of BETS in the ex vivo model; however, in the case of α-methyl cinnamaldehyde, BETS was visually detectable after 10days. CEO and its individual compounds have marked antibacterial activity against Aa. The effective results against planktonic and sessile Aa within reasonable time indicate that they can be used to prevent BETS.

Application of a Chitosan-Cinnamon Essential Oil Composite Coating in Inhibiting Postharvest Apple Diseases.

The purpose of this study was to explore the film-forming properties of cinnamon essential oil (CEO) and chitosan (CS) and the effect of their composite coating on postharvest apple diseases. The results demonstrated that the composite coating exhibits favorable film-forming properties at CEO concentrations below 4% (v/v). The effectiveness of the composite coating in disease control can be attributed to two factors: the direct inhibitory activity of CEO against pathogens in vitro and the induced resistance triggered by CS on the fruits. Importantly, the incorporation of CEO did not interfere with the induction of resistance by CS in harvested apples. However, it is noteworthy that the inhibitory effect of the CS-CEO composite coating on apple diseases diminished over time. Therefore, a key aspect of enhancing the preservation ability of fruits is improving the controlled release properties of CEO within CS coatings. This will enable a sustained and prolonged antimicrobial effect, thereby bolstering the fruit preservation capabilities of the composite coatings.

Antilisterial activity of cinnamon essential oil, pomegranate extract, or strawberry tree extract against Listeria monocytogenes in slices of dry-cured ham and pork loin.

Owing to concerns about the antimicrobial resistance of agents that can prevent the growth of Listeria monocytogenes in meat, researchers have investigated natural preservatives with antilisterial effects. However, in vivo application of essential oils and plant extracts usually results in reduced antimicrobial activity in meat products when compared to in vitro studies. This study aimed to evaluate the in vivo antimicrobial activity of cinnamon essential oil, pomegranate, and strawberry tree extracts in slices of dry-cured ham and pork loin against L. monocytogenes. Fragments of sterile dry-cured ham were inoculated with 100 μL cinnamon oil 0.5%, pomegranate, or strawberry crude extract. After 10 min, 100 μL of L. monocytogenes serotype 4b (104 colony-forming unit [CFU]/mL) was inoculated, and samples were incubated at 7 °C for 7 d to simulate the processing and storage temperature conditions of dry-cured meat products. L. monocytogenes was detected and quantified. Only strawberry extract presented significant differences (P < 0.05) from the control; thus, it was selected for the assay with 2% and 4% salt-treated pork loin. The strawberry tree extract significantly (P < 0.05) reduced the growth of L. monocytogenes in dry-cured ham. However, it could not reduce L. monocytogenes growth in pork loin, regardless of the salt concentration. This is the first report on the antimicrobial effect of strawberry tree leaf extract against L. monocytogenes in dry-cured ham.

Morphological, water barrier and biodegradable properties of sugar palm nanocellulose/starch biopolymer composites incorporated with cinnamon essential oils

Abstract In the past few decades, there has been increased interest in the use of natural fibers as reinforcement in bioplastic polymer composites because it is biodegradable. This is a result of the drawbacks of biodegradable polymer-based materials, which are brittle, intractable, and poorly water-sensitive. Natural fibers are chosen because they may be obtained organically, can be collected safely, and can be less expensive. In this work, cinnamon essential oil (CEO)/sugar palm nanocellulose/starch biopolymer composites were casted to investigate the morphological, water barrier and biodegradable properties. From the research, it shows water absorption increased regarding the plasticizer concentration. Besides, water vapor permeability (WVP) and solubility of the different concentration plasticizer used in the biopolymer shows an increasing trend due to high water content. All films degrade completely after the 12th day indicating the biodegradability of the film. Furthermore, seal strength for the lower concentrations of plasticizer shows the higher strength, while GS4.5 cannot be sealed due to high water contents. The images show the compatible films with slightly yellowish and transparent films. The variation of plasticizers did not affect the antibacterial activity of CEO inside the film forming solution. Overall, cinnamon essential oil (CEO)/sugar palm nanocellulose/starch biopolymer composites are good potential to enhance their suitability for food packaging applications.

Preparation of soluble complex carriers from Aloe vera mucilage/gelatin for cinnamon essential oil: Characterization and antibacterial activity

The present study aimed to fabricate Aloe vera (AV) mucillage/gelatin (GE) complexes as a carrier for cinnamon essential oil (CEO). Encapsulation efficiency and retention of CEO were used as parameters of choosing the best sample (1 GE:2AV and 30% CEO). Instrumental analysis of CEO-loaded AV/GE carriers revealed that CEO was well encapsulated within wall biopolymers. Also, the thermal stability of encapsulated CEO was higher than pure CEO confirmed by thermogravimetric analysis. Moreover, nanocarriers (29–308.9 nm) with an aggregated smooth structure were obtained. Simulated release study showed a high release of CEO (68.15%) from carriers after immersion in acidic conditions of gastric fluid. Antibacterial activity was investigated by the microdilution method and the results revealed that the antibacterial activity of CEO was escalated after encapsulation. The findings of this study pointed out that AV/GE complexes can be a promising carrier for the encapsulation of sensitive bioactive compounds. • Cinnamon essential oil (CEO) was encapsulated in gelatin/Aloe vera mucilage complex. • Encapsulated CEO was characterized by FTIR, XRD, TGA, SEM, DLS, and zeta potential. • Encapsulated CEO showed a sustained release in simulated gastrointestinal conditions. • Encapsulated CEO exhibited higher antibacterial activity than free form.

Preparation, characterization, and antimicrobial activity of cinnamon essential oil and cinnamaldehyde nanoemulsions

ABSTRACT Cinnamomum verum essential oil and its main component, cinnamaldehyde, were incorporated into nanoemulsions to improve their stability and activity. Oil-in-water (O/W) nanoemulsions were prepared using the high-energy ultra-sonication method. Cinnamon oil nanoemulsion exhibited a more vigorous DPPH radical scavenging activity (IC50 = 1.81 mg/L) than the standard α-tocopherol (IC50 = 9.16 mg/L). Cinnamaldehyde nanoemulsion exhibited the highest antibacterial action against Salmonella typhimurium and Staphylococcus aureus (MIC = 175 and 150 mg/L, respectively). It was also displayed the highest inhibition against Candida albicans (EC50 = 19.92 mg/L). Cinnamaldehyde nanoemulsion was the most active against mycelial growth of Aspergillus flavus and A. niger (EC50 = 38.20 and 134.80 mg/L, respectively). It also presented the highest activity against spore germination. This study describes antimicrobials and antioxidants based on nanoemulsions made from natural products that can be used to treat microbial infections.

The acaricidal activity of cinnamon essential oil: current knowledge and future perspectives

ABSTRACT Cinnamon is an evergreen plant species that is cultivated for medicinal and aromatic purposes. Essential oils obtained from this plant have potential industrial applications, as an antimicrobial and antioxidant agent. In addition, cinnamon essential oil has also demonstrated a promising antiparasitic effect against various ectoparasites, including ticks. In this review, we discuss the potential acaricidal activity of cinnamon essential oil, with a special focus on tick control. Furthermore, we identify some challenges that need to be addressed before future development and application of cinnamon essential oil as a botanical acaricide in tick control.

DETERMINATION OF ANTIOXIDANT, ANTI-AGING AND CYTOTOXICITY ACTIVITY OF THE ESSENTIAL OILS FROM CINNAMOMUM ZEYLANICUM

Antioxidant activity, anti-aging effects and cytotoxicity activity of cinnamon essential oils from Cinnamomum zeylanicum were investigated in this study. The antioxidant activities of the cinnamon essential oil at the concentrations of 125, 250, 500, and 1000 µg/mL were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2ʹ-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS). The inhibitory activities against collagenase, elastase and tyrosinase were evaluated for anti-aging effects. The antioxidant activity determined by DPPH and ABTS assays varied from 4.91 - 28.74% and 4.96 - 50.17%, respectively. In addition, cinnamon essential oil at all concentrations tested (100, 200, 500, and 1000 µg/mL) inhibited tyrosinase activity by 61.68 - 93.12 %, collagenase activity by 2.83 - 30.28 % and elastase activity by 4.37 - 33.92 %. The cytotoxicity activity determined by the diphenyltetrazolium (MTT) assay revealed that the cinnamon essential oil at the concentration less than 100 µg/mL did not exhibit cytotoxicity activity on human fibroblast cells while the percentage of cell viability decreased when exposed to this oil at the concentration higher than 150 µg/mL. These results demonstrated that the cinnamon essential oil has antioxidant, tyrosinase inhibitory, collagenase inhibitory, and elastase inhibitory activities. In addition, cinnamon essential oil at each effective concentration did not show any toxicity when tested on normal human fibroblast cell. Therefore, this essential oil could be a potential candidate for cosmetic and pharmaceutical products.

Enhancing effect of nanoemulsion on antimicrobial activity of cinnamon essential oil against foodborne pathogens in refrigerated Asian seabass (Lates calcarifer) fillets

A nanoemulsion approach to enhance antimicrobial performance of cinnamon essential oil as a natural preservative for the real food system was studied. The antimicrobial activity of cinnamon essential oil nanoemulsion (1429 and 11429 mg/L), in comparison to bulk cinnamon oil (488 and 11429 mg/L) and food industrial used sanitizer, sodium hypochlorite (10 mg/L), was investigated against refrigerated Asian seabass fillets artificially contaminated with Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and Vibrio parahaemolyticus. The results showed that cinnamon essential oil nanoemulsion (11429 mg/L) decreased approximately 0.5–1.5 log CFU/g of the initial number of bacteria when compared to the untreated samples. It also successfully inhibited the growth of those bacteria, especially V. parahaemolyticus, in fish fillets during storage (4 ± 2 °C), resulting to be the more effective agent when compared to bulk cinnamon oil and sodium hypochlorite. The improved antimicrobial activity of cinnamon essential oil against the pathogenic bacteria in fish fillets can be achieved by using nanoemulsion formulation.

The Antibacterial Activity of Cinnamon Essential Oil against Foodborne Bacteria: A Mini-Review

The Antibacterial Activity of Cinnamon Essential Oil against Foodborne Bacteria: A Mini-Review

Antimicrobial Activity of Selected Essential Oils on Pseudomonas Species Associated with Spoilage of Fish with Emphasis on Cinnamon Essential Oil

ABSTRACT Eight plant essential oils (cardamom, cinnamon, clove, eucalyptus, lemongrass, lime, nutmeg and rosemary) were evaluated for their antimicrobial activity against three Pseudomonas species associated with microbial spoilage of refrigerated tilapia. In vitro test of the essential oils, using disc-diffusion method, showed various degrees of antimicrobial activity against the Pseudomonas species. Cinnamon essential oil (CEO) had the highest antimicrobial activity, followed by clove essential oil. The remaining essential oils showed consistently weak activity. The antimicrobial efficiency of CEO against the Pseudomonas species was confirmed by potential minimum inhibitory concentration and minimum bactericidal concentration values, ranging between 0.125 and 0.375 µL/mL and 0.250–0.500 µL/mL, respectively. The anti-Pseudomonas activity of CEO was also tested in fish extract model at refrigeration temperature. The essential oil reduced the Pseudomonas viable count in fish extract but to a lesser extent than when it was applied at the same concentrations in culture medium. The chemical composition of CEO showed that the oil contained 79.1% cinnamaldehyde, which was suggested to be responsible for its antimicrobial activity. These results revealed the potential of CEO as a promising natural antimicrobial agent that could efficiently contribute to the control of spoilage bacteria and retard microbial spoilage of fresh fish.

In vitro anticariogenic and antibiofilm activities of toothpastes formulated with essential oils

ObjectiveThis study aimed to assess the antibacterial and antibiofilm effects of essential oils and herbal toothpastes against bacteria associated with oral diseases. MethodsThe minimum inhibitory concentration (MIC) and antibiofilm activity of 13 essential oils against Staphylococcus aureus, Streptococcus mutans, Lactobacillus lactis, and Enterococcus faecalis. were determined. Toothpastes were formulated with different concentrations of the most active essential oils, alone and in combination, and evaluated for antibacterial and antibiofilm activities. ResultsClove, oregano, thyme, and cinnamon essential oils were effective in inhibiting all bacterial strains. The antibacterial activity of cinnamon essential oil was similar to that of the control (0.12 % chlorhexidine gluconate mouthwash). Cinnamon essential oil was a strong inhibitor of S. mutans growth. The antibiofilm activity of clove, oregano, thyme, and cinnamon essential oils at 1, 2, and 4 × MIC against S. mutans did not differ from that of the control. In the hole-plate diffusion assay, 17 out of the 18 tested toothpastes produced an inhibition halo at least half as large as that of the control. Toothpastes containing clove, clove and oregano, or clove, oregano, thyme, and cinnamon essential oils were able to completely disrupt S. mutans biofilms, not differing from the control. Thyme essential oil was found to act synergistically with chlorhexidine against S. mutans. ConclusionsThe results indicate that clove, oregano, thyme, and cinnamon essential oils may be added to fluoride-free toothpastes to enhance inhibitory effects against bacteria associated with cavities and periodontal disease. Thyme essential oil may increase the efficiency of chlorhexidine-containing dentifrices.

Antimicrobial effects of cinnamon essential oil and cinnamaldehyde combined with EDTA against canine otitis externa pathogens.

The antimicrobial activity of cinnamon essential oil and cinnamaldehyde against bacterial and fungal pathogens associated with canine otitis externa, as well as the effect of their combination with EDTA were investigated. Antimicrobial susceptibility testing was performed using the broth microdilution method while spot-plating technique was used to determine their bactericidal activity. Time-kill kinetics and checkerboard assays were performed to confirm the bactericidal activity and combination effects of the compounds. Cinnamon oil and cinnamaldehyde exhibited antimicrobial activity against Gram-positive and Gram-negative pathogens, as well as Malassezia pachydermatis. Synergistic interaction was shown when EDTA (672μgml-1 ) was combined with cinnamon oil (41μgml-1 ) and cinnamaldehyde (22μgml-1 ) against Pseudomonas aeruginosa. Cinnamaldehyde exhibited significantly stronger antimicrobial activity than cinnamon bark oil. Cinnamon essential oil and cinnamaldehyde, either used alone or in combination with EDTA, were effective against the causative micro-organisms of canine otitis externa. The data suggest that cinnamaldehyde could be a promising antimicrobial agent against canine otitis externa. This study shows that cinnamon essential oil and cinnamaldehyde, especially the latter, could be used in combination with EDTA as novel treatment for sensitive and resistant bacterial and fungal pathogens involved in canine otitis externa.

Antibacterial activity of cinnamon essential oils and their synergistic potential with antibiotics.

The objective of this study was to evaluate the antibacterial activity of Cinnamomum cassia (cinnamon) essential oil (EO) alone and in combination with some classical antibiotics against three multidrug-resistant bacteria, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, to search a possible synergy. The antibacterial activity of all tested compounds was determined by agar disc diffusion and minimum inhibitory concentration assays. The checkerboard method was used to quantify the efficacy of cinnamon EO in combination with these antibiotics. Fractional inhibitory concentrations were calculated and interpreted as synergy, addition, indifferent, or antagonism. A synergistic interaction was shown against S. aureus with the combination cinnamon EO and ampicillin or chloramphenicol and against E. coli when cinnamon EO was combined with chloramphenicol. However, the combination of cinnamon oil and streptomycin displayed additive effects against all bacteria stains. The combinations of cinnamon EO and antibiotics can be used as an alternative therapeutic application, which can decrease the minimum effective dose of the drugs, thus reducing their possible adverse effects and the costs of treatment.

Antibacterial and anti-biofilm activity of cinnamon essential oil and eugenol

ABSTRACT: Biofilms are responsible for most of the interference caused by microorganisms in food processing. The aim of this study was to evaluate the cinnamon (Cinnamomum zeylanicum) essential oil and eugenol sanitizer and anti-biofilm activity against biofilms. Concentrations used of essential oil were 0.0% (control) 0.12%; 0.48%; 0.96% and 1.92%; the amount of eugenol was 0.76%. Concentrations were determined from other published studies. Number of viable cells and quantification the bacterial biomass were determined. Anti-biofilm treatment was effective in preventing the formation of biofilms. The 1.92% concentration was the most satisfactorily with Escherichia coli reduction of 5.91log CFUcm-2 and Staphylococcus aureus reduction of 5.17log CFUcm-2 (P&lt;0.05) biomass of the two bacteria. Sanitizing treatment was not effective in reducing biomass. Seen this, the cinnamon and eugenol essential oil may be promising alternatives for controlling biofilms.

Insecticidal Activity of Cinnamon Essential Oils, Constituents, and (E)- Cinnamaldehyde Analogues against Metcalfa pruinosa Say (Hemiptera: Flatidae) Nymphs and Adults

본 연구에서는 계피 정유 3종의 구성성분을 분석하였고, 미국선녀벌레에 대한 살충활성을 검정하였다. (E)-Cinnamaldehyde을 포함한 9종의 계피 정유 구성성분과 21종의 유사 물질을 미국선녀벌레 약충에 대해 살충활성을 검정한 결과, hydro-cinnamic acid가 반수치사농도 $1.55mg/cm^2$ 로 가장 좋은 살충활성을 보였으며, geranic acid도 $1.59mg/cm^2$ 로 높은 살충 활성을 보였다. Cinnamaldehyde를 포함한 hydro-cinnamaldehyde, (E)-cinnamaldehyde, cinnamdyl alcohol, cinnamyl acetate, dibutyl phtalate, anethole, a-cyano cinnamic acid, (s)-perillyl alcohol, methyl cinnamaldehyde, bonyl acetate 12종이 중간정도의 활성( $1.60-4.94mg/cm^2$ )을 보였으며, 다른 물질들은 살충활성이 낮거나 없었다. 미국선녀벌레 성충에 대해서는 eugenol 이 반수치사 농도 10.81 mg로 가장 높은 살충활성을 보였으며, geranic acid (30.68 mg)도 높은 살충력을 보였다. Cinnamaldehyde 등 9종이 반수 치사 농도 105.44~255.76 mg의 살충활성을 보였다. 다른 18종의 물질은 활성이 낮거나 없었다. 실제 포장인 인삼포장에 발생하는 미국선녀벌레에 대한 적용시험에서 cinnamon bark 정유와 cinnamon green leaf 정유가 각각 82.3%와 82.9%의 높은 살충활성을 보였다. 농업환경에서 고독성 합성살충제의 사용을 줄일 수 있는 방안으로 본 논문에서 선발한 계피정유가 미국선녀벌레의 약충 및 성충 방제에 유용한 수단으로 이용될 수 있을 것으로 사료된다. 【The insecticidal activity of the constituents of cinnamon essential oils and structurally related compounds against both the nymphs and adults of the citrus flatid planthopper Metcalfa pruinosa was examined using a direct-contact application. The toxicity of the cinnamon oil constituents and 21 (E)-cinnamaldehyde related compounds regarding the nymphs of M. pruinosa was evaluated using a leaf-dipping bioassay. Based on 24 h $LC_{50}$ values, hydro-cinnamic acid ( $1.55mg/cm^2$ ) is the most toxic compound, followed by geranic acid ( $1.59mg/cm^2$ ). The $LC_{50}$ values of 11 of the compounds including cinnamaldehyde are between $1.60mg/cm^2$ and $4.94mg/cm^2$ . Low toxicities and no toxicity were observed with the other 15 ( $5.24mg/cm^2$ to $13.47mg/cm^2$ ) and two compounds, respectively. Also, the toxicities of the cinnamon oil constituents and 21 cinnamaldehyde related compounds regarding the M. pruinosa adults were evaluated using a direct-spray method. The toxicity of eugenol (10.81 mg) is the most toxic compound for the adults of M. pruinosa, followed by geranic acid (30.68 mg). The $LC_{50}$ values of nine of the compounds including cinnamaldehyde are between 59.16 mg and 96.70 mg. Low toxicities and no toxicity were observed with the other 15 (105.44 mg to 255.76 mg) and three compounds, respectively. The spray formulations that comprise cinnamon bark and cinnamon green leaf oils resulted in 82.3% and 82.9% mortalities, respectively, toward the M. pruinosa adults in a ginseng field. Global efforts to reduce the level of highly toxic synthetic insecticides in agricultural environments justify further studies on cinnamon oils to ascertain whether the corresponding active principles can act as insecticides, when they are applied as a direct spray with contact action, for the control of M. pruinosa populations.】

Synergistic Effect of Cinnamon Essential Oil (Cinnamomum burmannii) and Doxorubicin on T47D Cells Correlated with Apoptosis Induction

Cinnamon (Cinnamomum burmannii) shows anticancer activity in several types of cancer cells. The aim of this study is to observe the cytotoxic activity of cinnamon essential oil (CEO) solely and its combination with doxorubicin, also the ability of the combination to induce apoptosis on T47D breast cancer cells. The CEO was prepared through distillation of dry cinnamon bark. Cytotoxic assay was performed by using MTT assay and apoptosis determination was done by using double staining with ethidium bromide and acridine orange. The result showed that CEO exhibited cytotoxic effect on T47D cells with IC50 values of 75 µg/ml. Moreover, CEO showed synergist effect with doxorubicin. The lowest combination index (CI) with CI values of 0,37 was obtained by combination of doxorubicin-CEO 37,5 µg/ml-1,25 µM. Treatment with CEO solely and its combination with doxorubicin showed apoptosis induction on T47D cells. The results of this study indicate the potency of CEO to be developed as co-chemotherapeutic agent of doxorubicin on breast cancer. Keywords: cinnamon essential oil, doxorubicin, T47D cells, combination cytotoxic