Rapid identification of various chemical components in Cinnamomi ramulus by UPLC-Q-Orbitrap-MS.

Cinnamomi ramulus (CR) is a common Chinese herbal medicine with a long history. It is often used to treat exogenous wind-cold diseases in clinic, but its chemical compositions remain to be studied. In this study, CR was extracted with 75% ethanol, and UPLC-Q-Orbitrap-MS combined with data post-processing method was used to identify the chemical components in the extract. Through this technology, the components in CR can be separated and accurately identified. A total of 61 compounds were identified, including 14 simple phenylpropanoids, 3 coumarins, 5 lignans, 14 flavonoids, 10 benzoic acids, 8 organic acids, and 7 others. This study confirmed the existence of these compounds in CR and speculated the cleavage pathways of each compound, which enriched the mass spectrometry data and cleavage rules. This study can provide a reference for CR and other research.

[Quality evaluation and grading standard discussion on Cinnamomi Ramulus].

This study explored the relationship between the appearance traits and internal components of Cinnamomi Ramulus pieces, so as to provide a reference for the quality evaluation and the formulation of grade standards. This study determined the appearance traits and index component contents of 41 batches of Cinnamomi Ramulus pieces in the core producing areas of Guangxi and Guangdongand established the HPLC characteristic map method. The weight of the pieces, the narrowest diameter, and the widest diameter of the tr ansverse section were used as the indices of appearance traits. The content of index components(cinnamic acid and cinnamalde hyde)was determined by the established content determination method. The chromatographic characteristics were determinedon a Waters XBridge C_(18)(4. 6 mm×250 mm, 5 µm) column with a mobile phase consisting of 0. 1% phosphoric acidacetonitrile and gradient elution at the flow rate of 1 mL ·min~(-1). The column temperature was 30 ℃, and the detection wavelength was 254 nm. Cluster analysis, principal component analysis, and other stoichiometric methods were used to analyze the correlation between theap pearance traits and the index/characteristic components of Cinnamomi Ramulus pieces and compare the qu ality differences of the piecesfrom different batches and plac es. The results showed that the larger weight, the narrowest diameter, andthe widest diameter of the tra nsverse section indicated lowercontent of main indexes/characteristic components, and there was a synergistic decreasing trend amongd ifferent components. The overall quality of Cinnamomi Ramulus pieces in Guangdong Province and Guangxi Province was similar, but there were still differences between different origins and different batches of the same origin. It is scientific and feasible to evaluatethe quality of Cinnamomi Ramulus pieces and establish grading standards based on the appearance traits and index/character istic components. The research provides a more scientific and comprehensive basis for the quality control evaluation and standardformulation of Cinnamomi Ramulus.

[Chemical constituents from Cinnamomi Ramulus decoction].

Six compounds were isolated from the ethyl acetate extracts of Cinnamomi Ramulus decoction by RP-18, silica gel, Sephadex LH-20 column chromatography, together with prep-HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the six compounds were identified as 4,5,10,11-tetrahydroxybisabol-7-ene(1), 4,5,10,11-tetrahydroxybisabolin(2), 1-phenyl-1,2,3-glycerol(3),(+)-lyoniresinol(4), benzoic acid(5), and decumbic acid(6). Compound 1 was a new bisabolene-type sesquiterpene, and compounds 2 and 3 were isolated from the Cinnamomi Ramulus for the first time. Moreover, the bisabolene-type sesquiterpene(2) was assayed for its anti-inflammatory activity and cytotoxicity to human pancreatic cancer cells(PANC-1 cells). RESULTS:: showed that compound 2 exhibited an inhibitory rate of 32.9% on nitric oxide(NO) at a dose of 40 µmol·L~(-1) and a proliferation inhibition rate of 14.5% against PANC-1 cells at a dose of 20 µmol·L~(-1). It did not demonstrate significant activity.

Effects of Taiwanese indigenous cinnamon (Cinnamomum osmophloeum) leaf hot-water extract on nonspecific immune responses, resistance against Vibrio parahaemolyticus, nonviable cells, and haemocyte subpopulations in white shrimp (Penaeusvannamei).

This study investigated the effects of Cinnamomum osmophloeum leaf hot-water extract (CLWE) on nonspecific immune responses and resistance to Vibrio parahaemolyticus in white shrimp (Penaeus vannamei). Firstly, a cell viability assay demonstrated that the CLWE is safe to white shrimp heamocytes in the concentration of 0-500 mg L-1. Haemocytes incubated in vitro with 10 and 50 mg L-1 of CLWE showed significantly higher response in superoxide anion production, PO activity, and phagocytic activity. In the in vivo trials, white shrimp were fed with 0, 0.5, 1, 5, and 10 g kg-1 CLWE supplemented feeds (designated as CLWE 0, CLWE 0.5, CLWE 1, CLWE 5, and CLWE 10, respectively) over a period of 28 days. In vivo experiments demonstrated that CLWE 0.5 feeding group resulted in the highest total haemocyte count, superoxide anion production, phenoloxidase activity, and phagocytic activity. Moreover, CLWE 0.5 supplemented feed significantly upregulated the clotting system, antimicrobial peptides, pattern recognition receptors, pattern recognition proteins, and antioxidant defences in white shrimp. Furthermore, the shrimp were infected with V. parahaemolyticus injections after 14 days of feeding as challenge test. Based on the challenge test result, both CLWE 0.5 and CLWE 5 demonstrated a strong resistance to V. parahaemolyticus. These two dosages effectively reduced the number of nonviable cells and activated different haemocyte subpopulations. These findings indicated that treatment with CLWE 0.5 could promote nonspecific immune responses, immune-related gene expression, and resistance to V. parahaemolyticus in white shrimp.

Cinnamaldehyde, A Bioactive Compound from the Leaves of Cinnamomum osmophloeum Kaneh, Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice by Inhibiting the NLRP3 Inflammasome.

Inflammatory bowel disease (IBD) comprises a group of idiopathic intestinal disorders, including ulcerative colitis and Crohn's disease, significantly impacting the quality of life for affected individuals. The effective management of these conditions remains a persistent challenge. The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, a complex molecular structure, regulates the production of pro-inflammatory cytokines such as interleukin-1ß. Abnormal activation of the NLRP3 inflammasome plays a pivotal role in the development of IBD, making it a compelling target for therapeutic intervention. Our research revealed that cinnamaldehyde (CA), a major bioactive compound found in the leaves of Cinnamomum osmophloeum kaneh, demonstrated a remarkable ability to alleviate colitis induced by dextran sulfate sodium (DSS) in a mouse model. This effect was attributed to CA's ability to downregulate the activation of the NLRP3 inflammasome and reduce the expression of pro-inflammatory mediators in the colon. In the mechanism study, we observed that CA inhibited the NLRP3 inflammasome in macrophages, at least partially, by enhancing the autophagic response, without reducing mitochondrial damage. These findings collectively suggest that CA holds significant potential as a therapeutic agent for enhancing the management of IBD, offering a promising avenue for further research and development.

Application of Cinnamomum burmannii Essential Oil in Promoting Wound Healing.

Skin wounds, leading to infections and death, have a huge negative impact on healthcare systems around the world. Antibacterial therapy and the suppression of excessive inflammation help wounds heal. To date, the application of wound dressings, biologics and biomaterials (hydrogels, epidermal growth factor, stem cells, etc.) is limited due to their difficult and expensive preparation process. Cinnamomum burmannii (Nees & T. Nees) Blume is an herb in traditional medicine, and its essential oil is rich in D-borneol, with antibacterial and anti-inflammatory effects. However, it is not clear whether Cinnamomum burmannii essential oil has the function of promoting wound healing. This study analyzed 32 main components and their relative contents of essential oil using GC-MS. Then, network pharmacology was used to predict the possible targets of this essential oil in wound healing. We first proved this essential oil's effects in vitro and in vivo. Cinnamomum burmannii essential oil could not only promote the proliferation and migration of skin stromal cells, but also promote M2-type polarization of macrophages while inhibiting the expression of pro-inflammatory cytokines. This study explored the possible mechanism by which Cinnamomum burmannii essential oil promotes wound healing, providing a cheap and effective strategy for promoting wound healing.

The crude extract obtained from Cinnamomum macrostemon Hayata regulates oxidative stress and mitophagy in keratinocytes.

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.

Comparative Chemical Composition and Acetylcholinesterase (AChE) Inhibitory Potential of Cinnamomum camphora and Cinnamomum tamala.

Cinnamomum species have applications in the pharmaceutical and fragrance industry for wide biological and pharmaceutical activities. The present study investigates the chemical composition of the essential oils extracted from two species of Cinnamomum namely C. tamala and C. camphora. Chemical analysis showed E-cinnamyl acetate (56.14 %), E-cinnamaldehyde (20.15 %), and linalool (11.77 %) contributed as the major compounds of the 95.22 % of C. tamala leaves essential oil found rich in phenylpropanoids (76.96 %). C. camphora essential oil accounting for 93.57 % of the total oil composition was rich in 1,8-cineole (55.84 %), sabinene (14.37 %), and α-terpineol (10.49 %) making the oil abundant in oxygenated monoterpenes (70.63 %). Furthermore, the acetylcholinesterase inhibitory activity for both the essential oils was carried out using Ellman's colorimetric method. The acetylcholinesterase inhibitory potential at highest studied concentration of 1 mg/mL was observed to be 46.12±1.52 % for C. tamala and 53.61±2.66 % for C. camphora compared to the standard drug physostigmine (97.53±0.63 %) at 100 ng/ml. These multiple natural aromatic and fragrant characteristics with distinct chemical compositions offered by Cinnamon species provide varied benefits in the development of formulations that could be advantageous for the flavor and fragrance industry.

Variations in Essential Oils from the Leaves of Cinnamomum bodinieri in China.

Cinnamomum plants are rich in natural essential oils, which are widely used as materials in the fragrance, insecticidal, antibacterial agent, pharmaceutical, and food industries; however, few studies have investigated the essential oil components of Cinnamomum bodinieri. Therefore, this study investigated the diversity of essential oils from the leaves of 885 individual C. bodinieri plants across 32 populations in five provinces. Essential oils were extracted by hydrodistillation, and then qualitative and quantitative analyses of the compounds were performed by GC-MS and GC-FID. A total of 87 chemical constituents were identified in the essential oils, including 33 monoterpenes, 48 sesquiterpenes, and six other compounds. The average oil yield was 0.75%, and individual oil yields ranged from 0.01% to 4.28%. A total of 16 chemotypes were classified according to variations in the essential oil chemical constituents of C. bodinieri, among which the camphor-type, citral-type, and eucalyptol-type were dominant. Moreover, the borneol-type, cymol-type, elemol-type, methylisoeugenol-type, and selina-6-en-4-ol-type were reported in C. bodinieri for the first time. The yield and principal components of the essential oils were mainly affected by altitude, temperature, and sunshine duration, among which altitude had the most significant effect; thus, low-altitude areas are more suitable for the synthesis and accumulation of essential oils. Based on the different characteristics of the essential oils in the leaves of C. bodinieri, several excellent populations and individuals were identified in this study. Moreover, the findings provide a foundation for breeding superior varieties and studying essential oil biosynthesis mechanisms in the future.

Cinnamomum japonicum Siebold Branch Extracts Attenuate NO and ROS Production via the Inhibition of p38 and JNK Phosphorylation.

Cinnamomum japonicum (CJ) is widely distributed in Asian countries like Korea, China, and Japan. Modern pharmacological studies have demonstrated that it exhibits various biological activities, including antioxidant and anti-inflammatory effects. However, most studies have confirmed the efficacy of its water extract but not that of its other extracts. Therefore, in this study, Cinnamomum japonicum Siebold branches (CJB: 70% EtOH extract) were separated using hexane, chloroform, ethyl acetate (CJB3), butanol, and water. Then, their antioxidative activities and phenolic contents were measured. Results revealed that the antioxidant activities and phenolic contents of CJB3 were higher than those of the other extracts. Further, the inhibitory and anti-inflammatory effect of CJB3 on lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) production and LPS-activated macrophages, respectively, was determined. CJB3 suppressed oxidative stress in LPS-activated cells and dose-dependently decreased LPS-stimulated ROS production. CJB3 reduced oxidative stress and reversed the glutathione decrease in LPS-activated RAW264.7 cells. The inhibitory and reducing effect of CJB3 on LPS-induced nitric oxide (NO) production and inducible NO synthase protein and messenger RNA levels, respectively, was investigated. CJB3 inhibited LPS-induced cytokine production and p38 and c-Jun N-terminal kinase (JNK) phosphorylation but not extracellular signal-regulated kinase phosphorylation. Overall, the study results suggest that CJB3 may exert its anti-inflammatory effects via the suppression of p38, JNK, and c-Jun activation.

Cinnamomum sp. and Pelargonium odoratissimum as the Main Contributors to the Antibacterial Activity of the Medicinal Drink Horchata: A Study Based on the Antibacterial and Chemical Analysis of 21 Plants.

Horchata, a herbal infusion drink from Ecuador containing a mixture of medicinal plants, has been reported to exhibit anti-inflammatory, analgesic, diuretic, and antioxidant activity. The antibacterial activity of each of the plants contained in the horchata mixture has not been fully evaluated. Thus, in this study, we analysed the antibacterial activity of 21 plants used in horchata, collected from the Ecuadorian Andes region, against bacterial strains of clinical importance. The methanolic extract of Cinnamomum sp. showed minimal inhibitory concentration (MIC) values of 250 µg/mL against Staphylococcus aureus ATCC25923 and Methicillin-resistant S. aureus (MRSA), while Pelargonium odoratissimum exhibited a MIC value of 500 µg/mL towards S. aureus ATCC25923. The high-performance liquid chromatography-diode array detector-tandem mass spectrometry (HPLC-DAD-MS/MS) analyses identified in Cinnamomum sp. epicatechin tannins, cinnamaldehyde, and prehelminthosporol molecules, whereas in P. odoratissimum, gallocatechin and epigallocatechin tannins, some flavonoids, and gallic acid and derivatives were identified. Finally, Cinnamomum sp. and P. odoratissimum showed partial inhibition of biofilm formation of S. aureus ATCC25923 and MRSA. Overall, our findings revealed which of the plants used in horchata are responsible for the antibacterial activity attributed to this herbal drink and exhibit the potential for Cinnamomum sp. and P. odoratissimum secondary metabolites to be explored as scaffolds in drug development.

Essential Oil Chemotypes and Genetic Variability of Cinnamomum verum Leaf Samples Commercialized and Cultivated in the Amazon.

Cinnamomum verum (Lauraceae), also known as "true cinnamon" or "Ceylon cinnamon" has been widely used in traditional folk medicine and cuisine for a long time. The systematics of C. verum presents some difficulties due to genetic variation and morphological similarity between other Cinnamomum species. The present work aimed to find chemical and molecular markers of C. verum samples from the Amazon region of Brazil. The leaf EOs and the genetic material (DNA) were extracted from samples cultivated and commercial samples. The chemical composition of the essential oils from samples of C. verum cultivated (Cve1-Cve5) and commercial (Cve6-c-Cv9-c) was grouped by multivariate statistical analysis of Principal Component Analysis (PCA). The major compounds were rich in benzenoids and phenylpropanoids, such as eugenol (0.7-91.0%), benzyl benzoate (0.28-76.51%), (E)-cinnamyl acetate (0.36-32.1%), and (E)-cinnamaldehyde (1.0-19.73%). DNA barcodes were developed for phylogenetic analysis using the chloroplastic regions of the matK and rbcL genes, and psbA-trnH intergenic spacer. The psbA-trnH sequences provided greater diversity of nucleotides, and matK confirmed the identity of C. verum. The combination of DNA barcode and volatile profile was found to be an important tool for the discrimination of C. verum varieties and to examine the authenticity of industrial sources.

Seasonal Variation in the Essential Oil Yield and Composition of Cinnamomum parthenoxylon (Jack) Meisner.

Cinnamomum parthenoxylon (Jack) Meisner is an important natural aromatic plant because its leaves are rich in essential oil. Linalool chemotype C. parthenoxylon was used as the research material in the present study. The leaf essential oil yield, the main chemical components, and their content were measured every month from January to December 2018 to study the seasonal variation in the yield and chemical components of C. parthenoxylon leaf essential oil. The results revealed that the essential oil yield and the main chemical component linalool in the essential oil of C. parthenoxylon leaves showed significant differences among months. The leaf essential oil yield and linalool content decreased to the lowest in March and increased rapidly from April to May. The leaf essential oil yield was the highest in May, and a relatively high yield was maintained from April to August. The linalool content in leaf essential oil was stable in other months except March. The leaf essential oil yield of C. parthenoxylon had a very significant positive correlation with monthly rainfall and monthly average temperature. Intense rainfall and high monthly average temperature were conducive to the synthesis and accumulation of C. parthenoxylon leaf essential oil. This study provided a theoretical basis for cultivating C. parthenoxylon as a raw material for spices and determining the best harvest time.

Cinnamomum: The New Therapeutic Agents for Inhibition of Bacterial and Fungal Biofilm-Associated Infection.

Due to the potent antibacterial properties of Cinnamomum and its derivatives, particularly cinnamaldehyde, recent studies have used these compounds to inhibit the growth of the most prevalent bacterial and fungal biofilms. By inhibiting flagella protein synthesis and swarming motility, Cinnamomum could suppress bacterial attachment, colonization, and biofilm formation in an early stage. Furthermore, by downregulation of Cyclic di-guanosine monophosphate (c-di-GMP), biofilm-related genes, and quorum sensing, this compound suppresses intercellular adherence and accumulation of bacterial cells in biofilm and inhibits important bacterial virulence factors. In addition, Cinnamomum could lead to preformed biofilm elimination by enhancing membrane permeability and the disruption of membrane integrity. Moreover, this substance suppresses the Candida species adherence to the oral epithelial cells, leading to the cell wall deformities, damage, and leakages of intracellular material that may contribute to the established Candida's biofilm elimination. Therefore, by inhibiting biofilm maturation and destroying the external structure of biofilm, Cinnamomum could boost antibiotic treatment success in combination therapy. However, Cinnamomum has several disadvantages, such as poor solubility in aqueous solution, instability, and volatility; thus, the use of different drug-delivery systems may resolve these limitations and should be further considered in future investigations. Overall, Cinnamomum could be a promising agent for inhibiting microbial biofilm-associated infection and could be used as a catheter and other medical materials surface coatings to suppress biofilm formation. Nonetheless, further in vitro toxicology analysis and animal experiments are required to confirm the reported molecular antibiofilm effect of Cinnamomum and its derivative components against microbial biofilm.

Activity in MCF-7 Estrogen-sensitive Breast Cancer Cells of Capsicodendrin from Cinnamosma fragrans.

BACKGROUND/AIM: Effect of capsicodendrin on the NF-κB pathway was studied in MCF-7 cancer cells. MATERIALS AND METHODS: The transcription factor assay was used to screen for NF-κB activity. The effect on IKKß, ICAM-1, and caspase-7 were studied using western blot. Caspase-1 was studied using Promega Caspase-Glo® assay. Reactive oxygen species (ROS) were detected using the fluorescent probe DCFH-DA. The potentiometric dye JC-1 was used to assess mitochondrial membrane potential (ΔΨm) and the cell cycle was examined using a fluorescence-activated cell sorter. RESULTS: NF-κB p65 inhibitory effect was IC50=8.6 µM and cytotoxic activity was IC50=7.5 µM. The upstream IKK and the downstream ICAM-1 were down-regulated. Sub G1-phase population increased to 81% after 12 h of treatment with capsicodendrin (10 µM) and there was no loss of ΔΨM. CONCLUSION: Increased levels of intracellular ROS promoted activity of caspase-1 and induced cell death in MCF-7 cells. Capsicodendrin may be a future anticancer agent that prevents the progression of metastatic breast cancer.

Effects of rhizosphere fungi on the chemical composition of fruits of the medicinal plant Cinnamomum migao endemic to southwestern China.

BACKGROUND: This study examined how rhizosphere fungi influence the accumulation of chemical components in fruits of a small population species of Cinnamomum migao. RESULTS: Ascomycota and Basidiomycota were dominant in the rhizosphere fungal community of C. migao. Pestalotiopsis and Gibellulopsis were associated with α-Terpineol and sabinene content, and Gibellulopsis was associated with crude fat and carbohydrate content. There were significant differences in rhizosphere fungal populations between watersheds, and there was no obvious change between fruiting periods. Gibberella, Ilyonectria, Micropsalliota, and Geminibasidium promoted sabinene accumulation, and Clitocybula promoted α-Terpineol accumulation. CONCLUSION: The climate-related differentiation of rhizosphere fungal communities in watershed areas is the main driver of the chemical composition of C. migao fruit. The control of the production of biologically active compounds by the rhizosphere fungal community provides new opportunities to increase the industrial and medicinal value of the fruit of C. migao.

Urease Inhibitory Kinetic Studies of Various Extracts and Pure Compounds from Cinnamomum Genus.

Urease is an enzyme that plays a significant role in the hydrolysis of urea into carbonic acid and ammonia via the carbamic acid formation. The resultant increase in pH leads to the onset of various pathologies such as gastric cancer, urolithiasis, hepatic coma, hepatic encephalopathy, duodenal ulcers and peptic ulcers. Urease inhibitors can reduce the urea hydrolysis rate and development of various diseases. The Cinnamomum genus is used in a large number of traditional medicines. It is well established that stem bark of Cinnamomum cassia exhibits antiulcerogenic potential. The present study evaluated the inhibitory effect of seven extracts of Cinnamomum camphora, Cinnamomum verum and two pure compounds Camphene and Cuminaldehyde on urease enzyme. Kinetic studies of potential inhibitors were carried out. Methanol extract (IC50 980 µg/mL) of C. camphora and a monoterpene Camphene (IC50 0.147 µg/mL) possess significant inhibitory activity. The Lineweaver Burk plot analysis suggested the competitive inhibition by methanol extract, hexane fraction and Camphene. The Gas Chromatography-Mass Spectroscopy (GC-MS) analysis of hexane fraction revealed the contribution of various terpenes. The present study targets terpenes as a new class of inhibitors that have potential therapeutic value for further development as novel drugs.

Evaluation of Motor Coordination and Antidepressant Activities of Cinnamomum osmophloeum ct. Linalool Leaf Oil in Rodent Model.

Cinnamomum plants (Lauraceae) are a woody species native to South and Southeast Asia forests, and are widely used as food flavors and traditional medicines. This study aims to evaluate the chemical constituents of Cinnamomum osmophloeum ct. linalool leaf oil, and its antidepressant and motor coordination activities and the other behavioral evaluations in a rodent animal model. The major component of leaf oil is linalool, confirmed by GC-MS analysis. Leaf oil would not induce the extra body weight gain compared to the control mice at the examined doses after 6 weeks of oral administration. The present results provide the first evidence for motor coordination and antidepressant effects present in leaf oil. According to hypnotic, locomotor behavioral, and motor coordination evaluations, leaf oil would not cause side effects, including weight gain, drowsiness and a diminishment in the motor functions, at the examined doses. In summary, these results revealed C. osmophloeum ct. linalool leaf essential oil is of high potential as a therapeutic supplement for minor/medium depressive syndromes.

Comparative spasmolytic effect between Cinnamomum tamala and Cinnamomum verum leaf essential oils and eugenol through in vitro and in silico approaches.

Cinnamomum tamala and Cinnamomum verum are known for their folk medicinal usage in treating gastrointestinal ailments. The spasmolytic activity of essential oils was studied using isolated rat ileum. The results indicate that C. tamala, despite having a lower content of eugenol (60%), shows a spasmolytic potential of 68.01 ± 2.63% (EC50 = 110.12 ± 13.58 µg/mL) while C. verum with rich eugenol (80%) shows lesser spasmolytic potential (38.96 ± 0.63%) and fails to attain an EC50 value. Upon comparison with standard eugenol's percentage of spasmolytic (35.68 ± 2.57%), it is evident that the action of these essential oils does not solely rely on the major component but the synergistic role in association with other components of the mixture influences the pharmacological action of the essential oils. In silico docking of phytochemicals of leaf essential oils with M2 (M2AChR) and M3 muscarinic (M3AChR) and nicotinic acetylcholine receptor (nAChR) was carried out to determine the type of receptors through which the essential oils had spasmolytic potential. The binding affinity for eugenol with nAChR shows a better docking score than M2AChR and M3AChR.

Improved adulticidal activity against Aedes aegypti (L.) and Aedes albopictus (Skuse) from synergy between Cinnamomum spp. essential oils.

Improved natural adulticidal agents against mosquito vectors are in urgent need, and essential oils from Cinnamomum plants can assume this role quite readily. Cinnamomum verum, C. cassia, and C. loureiroi essential oils (EOs) were extracted from the barks and evaluated for their chemical composition by GC-MS. The major constituent of the three EOs was cinnamaldehyde. WHO susceptibility tests on individual and combined EOs as well as cinnamaldehyde were conducted against female adults of Aedes aegypti and Aedes albopictus. All EO combinations exhibited a synergistic effect, manifesting a higher toxicity, with a synergistic value ranging from 2.9 to 6.7. Their increasing mortality value was improved between 16.0 to 41.7%. The highest synergistic effect was achieved by an EO combination of 0.5% C. cassia + 0.5% C. loureiroi, while the highest insecticidal activity was achieved by 2.5% C. verum + 2.5% C. cassia and 1% cinnamaldehyde, with a knockdown and mortality rate of 100% and a KT50 between 0.7 and 2.1 min. This combination was more toxic to both mosquito species than 1% w/v cypermethrin. These findings demonstrate that cinnamaldehyde and synergistic combinations of C. verum + C. cassia EOs and C. cassia + C. loureiroi EOs have a high insecticidal efficacy against Aedes populations.