Cinnamaldehyde Research Articles

Cinnamaldehyde for the Treatment of Microbial Infections: Evidence Obtained from Experimental Models.

Cinnamaldehyde (CNM) is a cyclic terpene alcohol found as the major compound of essential oils from some plants of the genus Cinnamomum (Lauraceae). CNM has several reported pharmacological activities, including antimicrobial, antivirulence, antioxidant, and immunomodulatory effects. These properties make CNM an attractive lead molecule for the development of anti-infective agents. In this descriptive review, we discuss the application of CNM in experimental models of microbial infection using invertebrate and vertebrate organisms. CNM (pure or in formulations) has been successfully applied in the treatment of infections caused by a range of bacterial (such as Cronobacter sakazakii, Escherichia coli, Listeria monocytogenes, Mycobacterium tuberculosis, Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, Streptococcus agalactiae, Vibrio cholerae) and fungal (such as Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans) pathogens. All these experimental evidence-based findings have promoted the use of cinnamaldehyde as the leading molecule for developing new anti- infective drugs.

Electrospun Mutualism–Inspired CA/CMA/PHMB ultrafine bimodal nanofibrous membrane for High–Performance, Antibacterial, and Mosquito–Repellent air filtration

Composite bio–based multifunctional air filtration is a great challenge and development trend for personal protection. This work was inspired by nature mutualism to produce bio–based and essential oil loaded nanofibrous membrane with multiple functions of high–performance, antibacterial, and mosquito–repellent. The cinnamaldehyde (CMA) and poly(hexamethylene biguanide) (PHMB) were introduced into the cellulose acetate (CA) polymer system to achieve functionalization, and then the CA/CMA/PHMB ultrafine bimodal nanofibrous membrane was prepared through one–step electrospinning. Compared to eugenol, the CMA contributed to the refinement of fiber and minimized the reduction of mechanical properties, thermal stability, and hydrophobicity. On the other hand, the PHMB enhanced jet splitting and synergistically improved antibacterial ability with CMA. The filtration efficiency for PM0.3, the pressure drop, and the quality factor were 99.78%, 59.5 Pa, and 0.1028 Pa−1, respectively. The bacteriostatic rates against Escherichia coli and Staphylococcus aureus, and the mosquito–repellent rate were 99.65%, 99.99%, and 92.7%, respectively. Lastly, the batch preparation of this solution was explored, which contributed to commercialization. This work provides a novel and simple approach to efficiently fabricate multifunctional high–performance air filter, which will promote the development of bio–based and sustainable air filter.

Identification of transient receptor potential channel genes and functional characterization of TRPA1 in Spodoptera frugiperda

Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities. Transient receptor potential (TRP) channels, which constitute a vast ion channel family, play pivotal roles in sensing the external environment and maintaining internal homeostasis in insects. TRP channels have been widely investigated for their critical roles in regulating various insect behaviors in recent years. In this study, we identified 15 TRP gene loci encoding 26 transcripts in the genome of S. frugiperda and analyzed their expression profiles at different developmental stages. The results revealed that S. frugiperda possesses four TRPC genes, six TRPA genes, one TRPM gene, two TRPV genes, one TRPN gene, and one TRPML gene, while a canonical TRPP is absent. Moreover, the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression system. The results showed that SfruTRPA1 is activated by temperature increases from 20 to 45°C, and there is no significant desensitization after repeated stimuli within the same temperature range. Additionally, SfruTRPA1 is activated by certain natural chemicals, including allyl isothiocyanate (AITC) and cinnamaldehyde (CA). These findings provide valuable insights to the TRP genes in S. frugiperda.

Incorporation of cinnamaldehyde, carvacrol, and eugenol into zein films for active food packaging: enhanced mechanical properties, antimicrobial activity, and controlled release.

Active packaging with antimicrobial functions to improve the quality and extend the shelf life of food products has gained great interest. Because commercial plastic packaging materials are not biodegradable and cause great environmental problems, plant-derived natural materials have been widely studied for the application of biodegradable packaging materials. Herein, we reported a study of essential oils (EOs)-loaded zein film. Cinnamaldehyde (CIN), carvacrol, and eugenol were added to equip the films with antimicrobial effects, while polyethylene glycol (PEG) and oleic acid (OA) were selected for the improvements of mechanical properties. The results showed that PEG efficiently improves the tensile strength and elongation (%E) of zein films compared to OA, although PEG induced weaker water barrier properties of the films than OA. FTIR spectra confirmed the formation of the hydrogen bonds between zein and PEG/OA. The EO-embedded zein film showed better antimicrobial effects than EO themselves. CIN-embedded films showed the highest antimicrobial effect among the three EOs. The sizes of the inhibition zones against Staphylococcus aureus of PEG-added zein films with 1%, 3%, and 5% CIN were 5.67, 12.67, and 16.67mm, which were larger than that of pure CIN, with the sizes of 0.00, 3.00, and 4.67mm, respectively. The developed films demonstrate a gradual release of EOs and show antimicrobial effects up to 96 h, indicating their high potential for the applications as active food packaging.

Application of lignin nanoparticles in polybutylene succinate based antifungal packaging for extending the shelf life of bread

The shift of using biodegradable materials for food packaging is becoming a global trend, as environmental consciousness constantly being raised. Enhancing the antimicrobial performance of biodegradable packaging has greatly received much attention for minimizing environmental impacts by reducing food and plastic wastes. This work explored the potential of utilizing an abundant industrial waste lignin as antimicrobial packaging. The effects of lignin nanoparticles (LNPs) incorporated into polybutylene succinate (PBS) composite film, against Aspergillus niger and Penicillium spp., the major microorganisms causing fungal spoilage in bread were investigated. At a low concentration of 0.5 % (w/v), LNPs showed fungal growth inhibition (FGI) in vitro of 51.89 % and 55.94 % against A. niger and Penicillium spp. When incorporated into PBS composite containing 5 % cinnamaldehyde (CIN), 1 % (w/w) LNPs showed stronger antifungal activities against Penicillium spp. than A. niger. Barrier properties and water contact angle were also enhanced with the presence of 1 % (w/w) LNPs in the PBS, but there were no effects on tensile strength, glass transition temperature, and melting temperature (Tm). Bread packed in PBS containing 1 % LNPs + 5 % CIN showed lowest yeast and mold count (YMC) of < 1.0 log CFU g–1, which was the same as the initial count, whereas YMC in other bread samples increased to > 2.0 log CFU g–1 after storage for 14 days at 25 ± 2 °C. Results suggest that LNPs in biodegradable materials such as PBS could help extend the shelf life of bread and possibly be applied to other food products that are susceptible to fungal spoilage.

Docetaxel-loaded pH/ROS dual-responsive nanoparticles with self-supplied ROS for inhibiting metastasis and enhancing immunotherapy of breast cancer

BackgroundAlthough stimuli-responsive nanoplatforms were developed to deliver immunogenic cell death (ICD) inducers to enhance cancer immunotherapy, the complete release of ICD inducers into the tumor microenvironment (TME) was limited by the inadequate supplementation of endogenous stimulus (e.g., reactive oxygen species (ROS)). To address this issue, we synthesized a self-responsive nanomaterial with self-supplied ROS, which mainly consists of a ROS responsive moiety HPAP and cinnamaldehyde (CA) as the ROS-generating agent. The endogenous ROS can accelerate the degradation of HPAP in materials to release docetaxel (DTX, an ICD inducer). In intracellular acidic environment, the pH-sensitive acetal was cleaved to release CA. The released CA in turn induces the generation of more ROS through mitochondrial damage, resulting in amplified DTX release. Using this self-cycling and self-responsive nanomaterial as a carrier, DTX-loaded pH/ROS dual-responsive nanoparticles (DTX/FA-CA-Oxi-αCD NPs) were fabricated and evaluated in vitro and in vivo.ResultsIn vitro experiments validated that the NPs could be effectively internalized by FA-overexpressed cells and completely release DTX in acidic and ROS microenvironments to induce ICD effect. These NPs significantly blocked 4T1 cell migration and decreased cell invasion. In vivo experiments demonstrated that the tumor-targeted NPs significantly inhibited tumor growth and blocked tumor metastasis. More importantly, these NPs significantly improved immunotherapy through triggering effector T-cell activation and relieving the immunosuppressive state of the TME.ConclusionsOur results demonstrated that DTX/FA-CA-Oxi-αCD NPs displayed great potential in preventing tumor metastasis, inhibiting tumor growth, and improving the efficacy of anti-PD-1antibody.Graphical

Antibacterial and anti‐biofilm properties of cinnamaldehyde‐loaded nanoliposomes against Listeria monocytogenes and Salmonella enteritidis adhered to stainless steel

SummaryThis study aimed to investigate the effect of cinnamaldehyde (CIN)‐loaded nanoliposomes (CIN‐NLs) on pre‐established biofilms of L. monocytogenes and S. enteritidis. The MIC and MBC values of CIN were 1.25 and 5 μg mL−1 against L. monocytogenes, respectively; while for S. enteritidis, MIC of 0.625 and MBC of 2.5 μg mL−1 were obtained. The CIN‐NLs displayed particle size in the range of 130.5–414.2 nm, polydispersity index (PDI) values in the range of 0.28–0.59, and ζ‐potential values above −30 mV. The encapsulation efficiency of CIN in NLs ranged from 7.47% to 27.42%. Transmission electron microscopy (TEM) displayed smooth spherical particles, and Fourier transform infrared spectroscopy (FT‐IR) results showed the successful loading of the CIN into NLs. The anti‐biofilm assays confirmed that the CIN‐NLs more efficiently prevented the formation of biofilm and extends the action time than that of free CIN. Therefore, NLs could improve the stability and long‐lasting antibacterial effect of CIN.

Electrophilic Agonists Modulate the Transient Receptor Potential Ankyrin-1 Channels Mediated by Insulin and Glucagon-like Peptide-1 Secretion for Glucose Homeostasis.

This pre-clinical study investigated the transient receptor potential ankyrin-1 (TRPA1) channels on modulating targets for glucose homeostasis using agonists: the electrophilic agonists, cinnamaldehyde (CIN) and allyl isothiocyanate (AITC), and the non-electrophilic agonist, carvacrol (CRV). A glucose tolerance test was performed on rats. CIN and AITC (5, 10 and 20 mg/kg) or CRV (25, 100, 300, and 600 mg/kg) were administered intraperitoneally (i.p.), and glycemia was measured. In the intestine, Glucagon-like peptide-1 (GLP-1) and disaccharidase activity were evaluated (in vivo and in vitro, respectively). Furthermore, in vivo and in vitro insulin secretion was determined. Islets were used to measure insulin secretion and calcium influx. CIN and AITC improved glucose tolerance and increased insulin secretion in vivo and in vitro. CRV was unable to reduce glycemia. Electrophilic agonists, CIN and AITC, inhibited disaccharidases and acted as secretagogues in the intestine by inducing GLP-1 release in vivo and in vitro and contributed to insulin secretion and glycemia. The effect of CIN on calcium influx in pancreatic islets (insulin secretion) involves voltage-dependent calcium channels and calcium from stores. TRPA1 triggers calcium influx and potentiates intracellular calcium release to induce insulin secretion, suggesting that electrophilic agonists mediate this signaling transduction for the control of glycemia.

Inactivation action of ultrasound-assisted cinnamaldehyde on planktonic and biofilm methicillin-resistant Staphylococcus aureus and its application in beef system

There has been a growing concern for methicillin-resistant Staphylococcus aureus (MRSA) contamination in the food industry. In the present study, the highest inactivation effect (5.80 log CFU/mL) was observed in simultaneous treatment compared with sequential treatment of ultrasound (US)-assisted cinnamaldehyde (CA). The absence of sublethal bacteria indicated US-assisted CA did not induce the tolerance or adaptation to MRSA cells. The results of SEM analysis indicated that the application of US-assisted CA resulted in severe damage to the cell membrane, as demonstrated by the highest fluorescence intensity of propidium iodide dye, intracellular substance leakage, and molecular docking analysis, as well as ATPase activity. Furthermore, US-assisted CA significantly disrupted energy metabolism, as evidenced by a reduction in ATP concentration, succinate dehydrogenase, and malate dehydrogenase activities. The exacerbation of ROS-induced damage to MRSA cells was observed due to the reduction in catalase and peroxidase activities. Additionally, a significant decrease (p < 0.05) in extracellular carbohydrates and proteins within the MRSA biofilm was noted on both glass and stainless-steel surfaces exposed to US-assisted CA. Ultimately, US-assisted CA treatment resulted in a maximum reduction (p < 0.05) of MRSA cells in beef meat, while maintaining color, pH, and sensory properties during an 8-day storage period at 4 °C. These findings suggested that simultaneous US-assisted CA treatment may serve as an alternative method for ensuring microbiological safety.

Trans-cinnamaldehyde loaded chitosan based nanocapsules display antibacterial and antibiofilm effects against cavity-causing Streptococcus mutans

ABSTRACT Background Dental caries is a multifactorial disease, and the bacteria such as Streptococcus mutans (S. mutans) is one of the risk factors. The poor effect of existing anti-bacterial is mainly related to drug resistance, the short time of drug action, and biofilm formation. Methods To address this concern, we report here on the cinnamaldehyde (CA) loaded chitosan (CS) nanocapsules (CA@CS NC) sustained release CA for antibacterial treatment. The size, ζ-potential, and morphology were characterized. The antibacterial activities in vitro were studied by growth curve assay, pH drop assay, biofilm assay, and qRT-PCR In addition, cytotoxicity assay, organ index, body weight, and histopathology results were analyzed to evaluate the safety and biocompatibility in a rat model. Results CA@CS NC can adsorb the bacterial membrane due to electronic interaction, releasing CA slowly for a long time. At the same time, it has reliable antibacterial activity against S. mutans and downregulated the expression levels of QS, virulence, biofilm, and adhesion genes. In addition, it greatly reduced the cytotoxicity of CA and significantly inhibited dental caries in rats without obvious toxicity. Conclusion Our results showed that CA@CS NC had antibacterial and antibiofilm effects on S. mutans and inhibit dental caries. Besides, it showed stronger efficacy and less toxicity, and was able to adsorb bacteria releasing CA slowly, providing a new nanomaterial solution for the treatment of dental caries.

A New Biodegradable Linear mPEG‐b‐poly(Schiff Base‐Acetal) Copolymer Carrier Co‐Delivery Cinnamaldehyde and Gemcitabine for Combined Anticancer Therapy

AbstractDue to significant pH difference among the healthy tissue, tumor tissue as well as intracellular endo/lysosome, constructing pH‐responsive biodegradable nanodrug delivery systems has received more and more attention. Herein, double‐end alkenylated acetal monomer (based on cinnamaldehyde (CA)) and double‐end sulfhydrylation Schiff base monomer were designed and synthesized, and three pH‐responsive biodegradable block copolymer mPEG‐b‐poly(Schiff base‐acetal) (P1), mPEG‐b‐poly(acetal) (P2), and mPEG‐b‐poly(Schiff base) (P3) were obtained by Michael addition reaction. All these polymers could be self‐assembled with gemcitabine (GEM) to form GEM‐loaded micelles. Proton nuclear magnetic resonance (1H NMR) and dynamic light scattering (DLS) experiments proved that these polymer micelles have good pH responsiveness. The size and morphology of both blank and GEM‐loaded micelles were characterized by DLS and scanning electron microscope (SEM). The GEM/P1, GEM/P2, and GEM/P3 micelles exhibited pH‐sensitive drug release properties and the GEM/P1 micelles has the relatively fastest drug release rate. Containing multiple acetal and Schiff base moieties GEM/P1 micelles showed fastest cellular internalized rate and best in vitro antitumor activity among all GEM‐loaded micelles.

Cyclic amplification of intracellular ROS boosts enzymatic prodrug activation for enhanced chemo-immunotherapy.

Tumor-associated enzyme activated prodrug is a potential strategy to overcome the limitations of chemotherapeutic agents. However, the efficiency of enzymatic prodrug activation is limited by the inability to reach adequate enzyme levels in vivo. Herein, we report an intelligent nanoplatform with cyclic amplification of intracellular reactive oxygen species (ROS) that significantly up-regulates the expression of tumor-associated enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1), to efficiently activate the prodrug of doxorubicin (DOX) for enhanced chemo-immunotherapy. The nanoplatform termed as CF@NDOX was fabricated by self-assembly of the amphiphilic cinnamaldehyde (CA) containing poly(thioacetal) conjugated with ferrocene (Fc) and poly(ethylene glycol) (PEG) (TK-CA-Fc-PEG), which further encapsulated the NQO1 responsive prodrug of DOX (NDOX). After CF@NDOX accumulates in tumors, the TK-CA-Fc-PEG with ROS responsive thioacetal group responds to endogenous ROS in tumor to release CA, Fc or NDOX. CA induces mitochondria dysfunction and elevates the intracellular hydrogen peroxide (H2O2) levels, which react with Fc to generate highly oxidative hydroxyl radical (•OH) through Fenton reaction. The •OH not only promotes ROS cyclic amplification but also increase the expression of NQO1 through Keap1-Nrf2 pathway regulation, which further boost the prodrug activation of NDOX for enhanced chemo-immunotherapy. Overall, our well-designed intelligent nanoplatform provides a tactic to enhance the antitumor efficacy of tumor-associated enzyme activated prodrug. STATEMENT OF SIGNIFICANCE: In this work, a smart nanoplatform CF@NDOX with intracellular ROS cyclic amplification for continuous upregulation of NQO1 enzyme expression was innovatively designed. It could utilize Fenton reaction of Fc to increase the level of NQO1 enzyme and CA to increase the level of intracellular H2O2, thereby facilitating the continuous Fenton reaction. This design allowed for a sustained elevation of the NQO1 enzyme, and a more complete activation of the NQO1 enzyme in response to the prodrug NDOX. This smart nanoplatform can achieve a desirable anti-tumor effect with the combined therapy of chemotherapy and ICD effects.

Fish gelatin films incorporated with cinnamaldehyde and its sulfobutyl ether-β-cyclodextrin inclusion complex and their application in fish preservation.

For food preservation, the packaging film needs to have higher antibacterial activity in initial phase and keep longer activity. In this study, cinnamaldehyde (CA) and its sulfobutyl ether-β-cyclodextrin inclusion complex (CA/S) were used to fabricate fish gelatin antibacterial composite films. The addition enhanced the elongation at break and light barrier property of the films. Film forming solution incorporated with CA and CA/S presented the most excellent inhibition ratio against Pseudomonas aeruginosa, which was 98.43±1.11% in initial period and still 82.97±4.55% at 72h. Further, the packaging solution of gelatin combined CA and CA/S effectively inhibited the growth of microorganisms during preservation of grass carp slices. Especially, the total volatile salt-based nitrogen (TVB-N) did not exceed 10mg/100g at the end of storage, indicating that the active coating could obviously extend the shelf life of fish muscle. This work provided a promising food packaging system with antimicrobial and environmentally friendly.

Functional properties and release characteristics of tea polyphenols-loaded gliadin films enforced by cinnamaldehyde

Protein-based packaging is beneficial for preserving the freshness of foods and extending their shelf-life. However, their mechanical and water-resistant properties limit their further usage. Herein, the gliadin was crosslinked by cinnamaldehyde (CA) and achieved by adding tea polyphenols (TPs) for active packaging. The physicochemical properties, functionalities, and TPs-release behavior were investigated. The results showed that the TPs-loaded gliadin films performed UV resistance and anti-digestion properties; the addition of 33 g/kg TPs had no effect on their mechanics, but increased their water content and improved their antioxidant properties. The CA crosslinking not only advanced the TPs-loading capacity but also improved the TPs release properties of the films, which showed a slow-release effect. Meanwhile, the release order of TPs from the films was acidic food-simulated solution, alcoholic food-simulated solution, fatty food-simulated solution, and common food-simulated solution. Consequently, the gliadin films could be ideal material for loading TPs and their film properties could also enforce by CA.

Curcumin-mediated photodynamic treatment extends the shelf life of salmon (Salmo salar) sashimi during chilled storage: Comparisons of preservation effects with five natural preservatives

The impact of curcumin-mediated photodynamic treatment (PDT) on the microbiological, physicochemical and sensory qualities of salmon sashimi has not been explored. Herein, this study aimed to evaluate the effects of PDT on the shelf-life quality of ready-to-eat salmon fillets during chilled storage (4 °C) in comparison with five widely investigated natural extracts, including cinnamic aldehyde, rosmarinic acid, chlorogenic acid, dihydromyricetin and nisin. From a microbial perspective, PDT exhibited outstanding bacterial inhibition, the results of total viable counts, total coliform bacteria, psychrotrophic bacteria, Pseudomonas spp., Enterobacteriaceae family, and H2S-producing bacteria were notably inactivated (p < 0.05) to meet the acceptable limits by PDT in comparison with those of the control group and natural origin groups, which could extend the shelf-life of salmon fillets from<6 days to 10 days. In the alteration of physicochemical indicators, PDT and natural extracts were able to maintain the pH value and retard lipid oxidation in salmon fillets, while apparently slowing the accumulation (p < 0.05) of total volatile basic nitrogen and biogenic amines, especially the allergen histamine, which contrary to with the variation trend of spoilage microbiota. In parallel, PDT worked effectively (p < 0.05) on the breakdown of adenosine triphosphate and adenosine diphosphate to maintain salmon fillet freshness. Additionally, the physical indicators of texture profile and color did not have obvious changes (p < 0.05) after treated by PDT during the shelf life. Besides, the sensory scores of salmon samples were also significantly improved. In general, PDT not only has a positive effect on organoleptic indicators but is also a potential antimicrobial strategy for improving the quality of salmon sashimi.

Cinnamaldehyde alleviates zearalenone-induced LS174T cell apoptosis, barrier dysfunction and mucin reduction through JNK/NF-κB signaling pathway

As a natural aldehyde organic compound, cinnamaldehyde (CA) is one of the main components of cinnamon essential oil with multiple bioactivities. In this study, we investigated the protective effects of CA on zearalenone (ZEA)-induced apoptosis, barrier dysfunction and mucin reduction, as well as underlying mechanisms in LS174T cells. In the present study, cells pre-treated with or without CA for 24 h were left untreated or subjected to ZEA for indicated time points Our results showed that 10 μM CA significantly prevented ZEA-induced cell viability decline, reversed ZEA-induced increase of the LDH level, cell cycle disruption and apoptosis in LS174T cells. Periodic acid-schiff (PAS) staining analysis showed that CA significantly alleviated the reduction of mucin secretion in LS174T cells caused by ZEA exposure. Western blot analysis showed that CA significantly reversed ZEA-induced reduction of the expression of mucin 2 (MUC2) and tight junction (TJ) proteins (claudin-1, claudin-3, ZO-1 and ZO-2) in LS174T cells. Notably, CA can significantly reduce the upregulation of the main effector of MAPK and NF-κB signaling pathways in LS174T cells. Further study showed that CA protects cells against ZEA-induced cellular damage through JNK/NF-κB signaling pathway in LS174T cells. Supplementation with CA might be an potential strategy to alleviate the damaging effect of ZEA on epithelial cells.

Integrated analysis of antimicrobial, antioxidant, and phytochemical properties of Cinnamomum verum: A comprehensive In vitro and In silico study

This study aims to investigate the chemical composition, antibacterial, antifungal, and antioxidant properties of C. verum essential oil (EO). The antimicrobial potential of C. verum EO was examined against a range of Gram-positive and Gram-negative bacteria, molds, and yeasts, including Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Escherichia coli, Klebsiella aerogenes, Salmonella enterica, Penicillium expansum, Candida albicans, and Candida tropicalis. The results revealed that C. verum EO exhibited significant broad-spectrum antimicrobial efficacy against all examined microorganisms, with inhibition zones ranging from 32.36 ± 2.42 to 13.9 ± 1.47 mm for bacteria and from 22.13 ± 2.25 to 15.26 ± 0.73 mm for fungi. Additionally, low values of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) ranging from 0.031 to 1.0% (v/v) for bacteria and from 0.125 to 1.0% (v/v) for fungi were obtained. The MBC/MIC and MFC/MIC ratios demonstrated that C. verum EO could potentially have bactericidal and fungicidal effects on microbial cells. Furthermore, the study also revealed that C. verum EO exhibited remarkable antioxidant activities using three complementary methods, namely DPPH, ABTS, and FRAP assays. The gas chromatography–mass spectrometry (GC-MS) analysis of C. verum EO showed the presence of cinnamaldehyde dimethyl acetal (64.53%), cinnamic aldehyde (35.36%), and α-copaene (0.11%). In addition to the in vitro investigation, a computational analysis was carried out using molecular docking and ADMET analysis. The primary aim of the molecular docking study was to understand how the ligands interacted with the specific proteins involved in the biological activities under study. This analysis provided valuable information about the binding modes, affinities, and potential interactions between the ligands and the target proteins. On the other hand, the ADMET analysis focused on evaluating various pharmacokinetic properties of C. verum EO, shedding light on its absorption, distribution, metabolism, and other relevant characteristics. In conclusion, the findings of this study indicate that C. verum EO possesses significant antimicrobial and antioxidant properties, making it a valuable source of natural preservatives and antimicrobial and antioxidant agents for use in various food products and drugs.

Unusual size effect of spinel Co0.5Fe0.5Al2O4 supported Pt catalysts on the selective hydrogenation of cinnamaldehyde

Pt/Co0.5Fe0.5Al2O4 catalysts with the average Pt particle size of 1.6–3.4 nm were prepared and applied to the selective hydrogenation of cinnamaldehyde (CAL). Not only the TOF was promoted from 0.19 to 2.70 s−1, but also the selectivity to cinnamyl alcohol (COL) was improved from 68% to 94%, with the increase of Pt particle size. Stronger interaction occurred between Co0.5Fe0.5Al2O4 and smaller-sized Pt particles, resulting in electron-deficient Pt particles, so that CO and CC bond could be activated simultaneously. However, electron-rich Pt species existed on Pt/Co0.5Fe0.5Al2O4 with larger Pt size, which is beneficial for the preferential activation of CO bond.

Reactant enrichment in hollow void of Pt NPs@MnOx nanoreactors for boosting hydrogenation performance.

In confined mesoscopic spaces, the unraveling of a catalytic mechanism with complex mass transfer and adsorption processes such as reactant enrichment is a great challenge. In this study, a hollow nanoarchitecture of MnOx-encapsulated Pt nanoparticles was designed as a nanoreactor to investigate the reactant enrichment in a mesoscopic hollow void. By employing advanced characterization techniques, we found that the reactant-enrichment behavior is derived from directional diffusion of the reactant driven through the local concentration gradient and this increased the amount of reactant. Combining experimental results with density functional theory calculations, the superior cinnamyl alcohol (COL) selectivity originates from the selective adsorption of cinnamaldehyde (CAL) and the rapid formation and desorption of COL in the MnOx shell. The superb performance of 95% CAL conversion and 95% COL selectivity is obtained at only 0.5MPa H2 and 40min. Our findings showcase that a rationally designed nanoreactor could boost catalytic performance in chemoselective hydrogenation, which can be of great aid and potential in various application scenarios.

PLA thermoformed trays incorporated with cinnamaldehyde and carvacrol as active biodegradable bakery packaging

Poly(lactic acid) (PLA) with enhanced antimicrobial functions can be used as sustainable food packaging to control microbial growth and reduce waste. PLA trays containing carvacrol (CAR) and cinnamaldehyde (CIN) as natural antimicrobial essential oils (EOs) were developed by cast sheet extrusion and thermoforming. Infrared spectra indicated interaction between CAR and CIN with PLA, involving the CO bond in carbonyl and the C-H bond in methyl groups of PLA molecules. Incorporation of CAR and CIN produced clear PLA trays with modified X-ray diffraction angles of amorphous PLA structures. Shrinkage of the trays occurred at high EO levels, reducing tray depth. Adding both CAR and CIN reduced tray mechanical strength due to plasticization and water vapor permeability but increased oxygen permeability, suggesting the major effect of hydrophilicity-hydrophobicity on permeability. PLA with CAR (5 % and 8 %) had superior antimicrobial capacity against Escherichia coli than PLA/CIN, while trays containing both EOs effectively delayed mold growth as active cake packaging, with CAR showing higher mold inhibition. Accordingly, EO types and concentrations controls mechanical strength, barrier properties and shrinkage of thermoformed PLA trays, while enhancing microbial controls in bakery products.