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Selective hydrogenation of cinnamaldehyde (CAL) toward cinnamyl alcohol (COL) is an extremely important and challenging reaction. Herein, a series of PtxFey-Al2O3 bimetallic catalysts with varied Pt to Fe ratios were prepared by incipient wetness impregnation method. The introduction of Fe significantly modifies the electronic and surface properties of Pt, which clearly enhances the C=O hydrogenation selectivity. Among all the catalysts, Pt3Fe-Al2O3 displays the best catalytic performance and the conversion of CAL is 96.6% with 77.2% selectivity of COL within 1 h. In addition, Pt3Fe-Al2O3 had excellent reusability with 76% COL selectivity after five runs of the recycle process. Further characterization of the fresh, used and cycled catalysts revealed that the structure and electronic state of the synthesized PtxFey-Al2O3 are unchanged after hydrogenation reaction. The identical-location transmission electron microscopy (IL-TEM) results revealed that the interaction between the nanoparticles and the supports was strong and the catalyst was relatively stable.

Hydrogenation of aldehydes (RHO) is one of the frequently used reactions in organic synthesis and pharmaceuticals industries. In this contribution, we have synthesized control shaped and nano-sized tetragonal zirconia (t-ZrO2), palladium supported on zirconia (Pd/t-ZrO2) and nickel promoted palladium supported on zirconia (Ni-Pd/t-ZrO2) though modified microwave irradiation method. All the prepared samples were characterized by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray Diffractometry (XRD), Thermal Gravimetric Analysis (TGA), Brunauer-Emmett-Teller (BET) surface area and pore size analysis, and Fourier Transform Infrared Spectroscopy (FT-IR). Theoretical calculation (DFT) revealed high interaction of Pd with t-ZrO2(101) surface. Furthermore, adsorption energy, support relaxation and charge transfer studies confirmed the stability of Pd on t-ZrO2(101) surface. The catalytic activity of catalysts was tested for cinnamaldehyde (CAL) hydrogenation in a modified microwave reactor. The comparative study of microwave irradiated (MW) and conventional heating (C-Heating) systems show supremacy of MW over C-Heating by a factor of 46% under optimal reaction parameters for Pd/t-ZrO2 catalyst. The stability, life span, conversion and selectivity of Pd/t-ZrO2 under MW system suggest the applicability of the catalysts for a variety of organic hydrogenation reactions.

Differences in the activity of Pd/WO3 and Pd/MoO3 (Pd loading 0.4–4 wt%) catalysts in competitive hydrogenations of the C C and C O groups in polyfunctional reagents have been studied as a function of two effects: (1) the in situ formation of hydrogen bronzes, HxWO3 and HxMoO3, and (2) the electronic interaction between the supports and the metallic Pd. The cinnamaldehyde (CAL), furfural (FU) and 5-hydroxymethylfurfural (HMF) were hydrogenated under mild reaction conditions. The formation of hydrogen bronzes in Pd/WO3 and physical mixture of Pd/WO3 with supporting WO3 oxide upon exposure to H2 was also studied using the gas flow-through microcalorimetry. In both Pd/MoO3 and Pd/WO3 catalysts, the electronic interactions contributed to the promotion of selectivity toward the C O hydrogenation in CAL and FU, yet in Pd/MoO3 this effect was much more pronounced. On the other hand, apart from increasing the overall reaction rate, the formation of hydrogen bronzes remarkably enhances the C C hydrogenation in CAL, as well as the decarbonylation of FU to furan and hydrogenolysis of C–OH in HMF to 5-methylfurfural. The bronze effects are significantly stronger in HxWO3, compared to HxMoO3, which may be related to higher H-species mobility and weaker H-bonding in the W–O–H (54 kJ/mol H2) than in the Mo–O–H (100 kJ/mol H2). This may also explain very high tendency of Pd/WO3 to furan ring hydrogenation in FU and HMF as well as almost selective (>98%) hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol.

Although the selective hydrogenation of α,β-unsaturated aldehyde to unsaturated alcohol (UOL) is an extremely important transformation, it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C C hydrogenation over the C O hydrogenation. Herein, we report that iridium nanoclusters (Ir NCs) confined within hollow MIL-101(Fe) expresses satisfied reaction activity (93.9%) and high selectivity (96.2%) for the hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) under 1 bar H2 atmosphere and room temperature. The unique hollow structure of MIL-101(Fe) benefits for the fast transport of reactant, ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe) than the counterparts which Ir NCs were on the surface of MIL-101(Fe). Furthermore, The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs, owing to the electron transfer from Ir to MIL-101(Fe), can interact with oxygen lone pairs, and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe) can strongly interact with C O bond, which contributes to a high selectivity for COL. This work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.

In this study, a novel eco-friendly chitosan-cinnamaldehyde cross-linked nanoparticles (CSN) were synthesised via a green route and deposited, in alternating combination with sodium tripolyphosphate (TPP), over polyester (PET) nonwoven fabric using layer-by-layer (L-B-L) coating technique. The successful deposition of a nano-level coating (upto 684.7 nm) of 10.5 bi-layers of CSN and TPP, i.e. (CSN/TPP)10.5, with CSN at the top, was achieved at individual fibre surface as confirmed via scanning electron microscopy. Fabric coated with (CSN/TPP)10.5 showed remarkable antibacterial activity against both the Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, even with a low concentration of the nanoparticles (0.1 w/v). Moreover, the coating material possesses very low toxicity as revealed by the cytotoxicity test. The developed fabric could also adsorb metal ions like Pb2+, Cu2+, Fe3+, Ni2+, Zr4+ and Cd2+, etc. from water. The coating was found to be stable in alkaline and neutral pH environments. The slight reduction in the pore dimensions, air permeability and tensile strength of fabric after coating were insignificant with respect to its potential applications in developing health care products, medical and health care textiles and dry or wet purification media.

Staphylococcus aureus causes food intoxication and can become resistant to a large number of antibacterial drugs. Thus, there is a growing interest in understanding the mechanisms involved in the adaptation of bacterial cells to environmental stresses or to antimicrobial agents. In this context, we evaluated the cinnamaldehyde (CIN) MBC for two contaminating food strains of S. aureus (GL 5674 and GL 8702) and tested the hypothesis that exposure of these strains to sublethal CIN concentrations and pH values could increase their resistance to this antimicrobial agent, to acid stress, and also to stress at high temperatures. Thus, the ability of the strains to adapt to CIN and acid stress was evaluated, as well as the cross-adaptation between acid stress and CIN. Strains GL 5674 and GL 8702 of S. aureus are sensitive to CIN in MBCs of 0.25 and 0.5% respectively, proving the antibacterial potential of this compound, but we proved the hypothesis of homologous adaptation to CIN. The strains grew in concentrations higher than the MBC after being previously exposed to sublethal concentrations of CIN. We also observed heterologous adaptation of the strains, which after exposure to the minimum pH for growth, were able to grow in concentrations of CIN greater than the MBC. GL 5674 showed greater adaptive plasticity, considerably reducing its minimum inhibitory pH and increasing its MBC after adaptation. Our results show a positive effect of adaptation to CIN on the resistance of S. aureus (P < 0.0001) to CIN at a temperature of 37°C. However, in the absence of adaptation, the presence of CIN in S. aureus cultures maintained at 37°C showed an efficient bactericidal effect associated with increased exposure time. Our results call attention to the conscious use of CIN as an antimicrobial agent and present the possibility of using CIN, in association with a temperature of 37°C and an exposure time of 35 min, as a promising measure for the elimination of pathogenic strains. HIGHLIGHTS

Au-Pd bimetallic nanoparticles (NPs) supported on SnNb2O6 ultrathin nanosheets (SN) were developed as multifunctional photocatalysts for the selective hydrogenation of cinnamaldehyde (CAL) to hydrocinnamaldehyde (HCAL) under visible light irradiation. A representative catalyst (Au6-Pd1/SN) exhibits optimum performances with 99.8% conversion and 91.0% selectivity. The structure and surface properties of the prepared samples were revealed by SEM, TEM, BET, TPD, XPS, and EPR. The results of in situ FTIR spectra and NH3-TPD reveal that the rich surface Lewis acid sites on SN can chemisorb and activate CAL via the C = C…Nb coordination. EPR experiments indicate that H2 would dissociate to activated H atoms on Pd NPs following a photopromoted surface catalytic process. Experimental results suggest that Au NPs reduce the over hydrogenation of HCAL by inhibiting the formation of Pd-H species. The superior catalytic performance is attributed to a synergistic effect of Au, Pd NPs and SN. Finally, a possible synergetic mechanism for Au-Pd/SN is proposed to illustrate the photocatalytic process. This work offers a reference to guide a novel and more effective photocatalyst design for precise organic synthesis driven by sunlight.

Chemoselective hydrogenation of unsaturated aldehyde to unsaturated alcohol has attracted growing interests in recent years due to its widespread applications in fine chemicals. However, the hydrogenation of the C=O bond was thermodynamically and kinetically unfavorable over the hydrogenation of the C=C bond. Thus, to obtain the unsaturated alcohol from the unsaturated aldehyde is very difficult in most of the catalytic systems. In this work, ZnAl-hydrotalcite-supported cysteine-capped Au25 nanoclusters were used as the precatalysts for chemoselective hydrogenation of cinnamaldehyde to cinnamyl alcohol. The catalyst showed stable high selectivity (~ 95%) at prolonged reaction time and complete conversion of the substrate. According to the results of the control experiments, the in-situ DRIFTS of the substrate under high pressure of hydrogen and the 27Al MAS-NMR spectroscopy, we proposed that the difference of the preferential adsorption of the C=O bond to that of the C=C bond was derived from the nature of the support of the gold catalysts.

Mesoporous TS-1 microspheres (MTS-1-MS) were applied to load Pt-Fe bimetallic components with different Fe/Pt molar ratios for the liquid-phase selective hydrogenation of cinnamaldehyde (CAL) to produce cinnamyl alcohol (COL). Combining the XRD and XPS characterization results, Fe dopant co-existed as PtFe fcc alloy or FeOx species, which modified the electronic properties of Pt active sites through the electron transfer from Fe to Pt, therefore, the catalytic performance was improved remarkably with the Fe-doped Pt/MTS-1-MS catalyst. As a result, the PtFe0.25/MTS-1-MS-350 catalyst, which contains Fe amount with a Fe/Pt molar ratio of 0.25 and was calcined at 350 °C before reduction in hydrogen at 400 °C, furnished 95.7% CAL conversion and 89.2% COL selectivity with an initial activity (in terms of TOF value) reaching 19440 h−1, much better than its analogue Pt/MTS-1-MS-350, which only showed 56.6% CAL conversion and 74.4% COL selectivity under the same conditions. To the best of our knowledge, it is one of the most active Pt-Fe bimetallic catalysts up to now. Moreover, the PtFe0.25/MTS-1-MS-350 catalyst can also be cycled for at least 9 times without obvious loss in activity or COL selectivity. Furthermore, theoretical calculations based on several simplified surface models were conducted using the density-functional theory (DFT) to reveal the differences in electronic structures and geometric properties caused by Fe dopant and to explain the reason why C O hydrogenation was preferential on the PtFe0.25/MTS-1-MS-350 catalyst from the perspective of CAL adsorption and COL desorption on/from Pt-Fe surface.

Selective hydrogenation of the carbonyl functional group of α,β-unsaturated carbonyl compounds affords industrially important allylic alcohols. However, achieving the selective reduction of the carbonyl group in the presence of the activated olefinic group is challenging. Therefore, the development of a highly chemoselective, efficient, and recyclable catalyst for this transformation is greatly desirable from the industrial and environmental viewpoints. In this study, a Ru-immobilized bisphosphine-based porous organic polymer (Ru@PP-POP) was used as an efficient heterogeneous catalyst for chemoselective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol with high chemoselectivity (98%) and excellent recyclability. To the best of our knowledge, the catalyst, Ru@PP-POP showed a high turnover number (970) and a high turnover frequency (240 h−1) which is the best activity obtained using a phosphine based heterogeneous Ru-catalyst in this transformation.

Functional group hydrogenation of α-β unsaturated aldehydes to fine chemicals is a potential process in organic synthesis. In this study, we demonstrate the complete functional group hydrogenation of cinnamaldehyde (CAL) to hydrocinnamyl alcohol (HCOL) over magnesium aluminium hydrotalcite (MAHT) having bimetallic nickel/ruthenium (1.3% Ni and 0.74% Ru) species (MANR–HT). The catalyst shows complete conversion of CAL with 97.5% selectivity of HCOL at 150 °C and 1 MPa H2 pressure. The synergic effect of bimetallic Ni/Ru and basicity of the HT material facilitated the high catalytic activity of MANR–HT in the CAL hydrogenation. The catalyst also demonstrated comparable activity even after several runs.

Due to coexistence of two conjugated unsaturated functional groups in cinnamaldehyde (CAL), exploring efficient catalysts with desirable selectivity to highly value-added products is still challengeable for the selective hydrogenation of CAL. Herein, NixFe1-xAl2O4+δ spinel composite metal oxides (SCMOs) supported Pt catalysts were developed and proved to be active and selective for the selective hydrogenation of CAL. Moreover, the selectivity switch can be realized just by changing the Ni/(Fe + Ni) molar ratios in NixFe1-xAl2O4+δ SCMOs. As a result, the excellent cinnamyl alcohol (COL) selectivity (~92.2%) and hydrocinnamaldehyde (HCAL) selectivity (~80.7%) were achieved on Pt/FeAl2O4+δ and Pt/NiAl2O4+δ, respectively. Based on the kinetic investigation of further hydrogenation of semi-hydrogenated product, the reason for the selectivity switch with Pt/NixFe1-xAl2O4+δ was revealed. In combination with detailed characterization, the excellent COL selectivity on Pt/FeAl2O4+δ can be attributed to more Pt(1 1 1) facets and FeOx species which can facilitate the preferential activation of C O bonds; while the high HCAL selectivity on Pt/NiAl2O4+δ is owing to the fact that there are more low coordinated active sites and two neighbouring Pt sites.

The study demonstrates the use of chitosan as a carrier agent of designed antifungal formulation (CME 4:1:1) based on a combination of plant compounds such as trans- cinnamaldehyde (C), methyl eugenol (M), and estragole (E). The formulation was encapsulated inside the chitosan biopolymer nanomatrix (Ne-CME) and characterized by SEM, FTIR, and XRD. The Ne-CME exhibited enhanced antifungal and aflatoxin B1 inhibitory effect compared to the individual compounds and unencapsulated form. Ne-CME (0.04 μl/ml) caused significant protection of Piper longum fruit from fungal (90.05%) and aflatoxin B1 (100%) contamination and had no significant negative effects on its nutritional properties. In addition, the probable antifungal mechanism of Ne-CME was investigated using in-silico (effect on Omt-1 and Vbs structural genes of AFB1 biosynthesis) and biochemical (perturbances in the cell membrane, carbohydrate catabolism, methyl-glyoxal, mitochondrial membrane potential, and antioxidant defense system) assay.

The effect of the reduction temperature (300 °C, 400 °C, 500 °C and 600 °C) in cobalt SiO2 core-shell catalysts for chemoselective hydrogenation of cinnamaldehyde is reported. The Co-CoO@SiO2 catalysts structures were synthesized starting from a calcined Co3O4@SiO2 nanostructure obtained using a solvothermal method for the core (Co3O4) and a modified Stober method for the porous shell (SiO2) submitted to different reduction temperatures. The initial Co3O4@SiO2 structure and the derived Co-CoO@SiO2 catalysts were characterized by AAS, TG/DTG, TPR, TEM, XRD, XPS and SBET. The increase in the metallic Co content along with the reduction temperature increased the total conversion of cinnamaldehyde in the liquid-phase hydrogenation reaction. The highest selectivity towards the unsaturated alcohol over Co-CoO@SiO2-500 °C catalyst was attributed to an optimum Co/CoO surface ratio. A large chemical and mechanical stability of the Co-CoO@SiO2 structure was evidenced after five consecutive reaction cycles, revealing the beneficial effect of the core-shell architecture towards cobalt leaching in liquid-phase reactions.

Carboxymethylcellulose (CMC)-based film packaging enriched with plant-sourced cinnamaldehyde (CIN) and zinc oxide nanoparticles (ZnONPs) of simple synthesis were prepared in this work. Then, the physico-mechanical and barrier properties and antifungal activities of CMC-based films, including pristine CMC, CIN/CMC, ZnONPs/CMC, ZnONPs/CIN/CMC were investigated. The results indicated that the ZnONPs incorporation produced a nanocomposite film with low transparency, good flexibility and high mechanical resistance. Furthermore, the water barrier capacity and antifungal performance of CMC-based films were significantly improved with the addition of CIN. CMC-based composite film incorporating with both CIN and ZnONPs, in turn, exhibited satisfactory mechanical characterizations, excellent barrier capacities against water and oxygen molecules and anti-Aspergillus niger activity. Moreover, ZnO/CIN/CMC nanocomposite film was significantly effective at inhibiting the weight loss and firmness of cherry tomatoes and in decreasing the total acidity content of these fruits after storage. Our results suggested that the ZnO/CIN/CMC nanocomposite film packaging can improve the cherry tomatoes quality by suppressing physiological the metabolic activities of the fruits during postharvest storage period.

A controlled-release antibacterial active food packaging film was prepared from polylactic acid (PLA), poly (e-caprolactone) (PCL), carbon nanotubes (CNTs), and cinnamaldehyde (CIN) by solvent evaporation method. The properties and antibacterial activities of CIN loaded PLA/CNTs/CIN film was characterized. Furthermore, the release behavior of CIN from PLA-based antibacterial film was quantified. The introduction of CNT and CIN would not significantly affect the barrier properties of PLA-based film, but would significantly enhance the UV resistance of the film. The co-action of CNTs and CIN led to the decrease of the glass transition temperature of the film and enhanced the elongation at break of the film. The PLA/CNTs/CIN film could continuously release CIN for 21 days in ambient storage, and antibacterial effect of the film on Staphylococcus aureus and Escherichia coli could be maintained for 21 days, during which the antibacterial effect gradually reduced and maintained for 7 days longer than the film without CNTs. According to the research results, The PLA/CNTs/CIN composites have great application potential in antibacterial active food packaging film.

In this work, an alloy catalyst with C@PtGa interface structure was synthesized under H2/CO2 atmosphere by using PtCl62−/MgAlGa-LDHs as precursor. Cs-corrected STEM, EELS and CO chemisorption clearly confirmed the PtGa alloy particles were well covered by amorphous carbon thin layer with the characteristics of porous and permeable. In selective cinnamaldehyde hydrogenation, the C@PtGa catalyst showed a higher selectivity than both bare PtGa catalyst and Ga2O3@PtGa catalyst. The enhanced selectivity was attributed to the geometric decoration of carbon layer as well as the formation of electron-rich Pt sites at C@PtGa interface, which optimized the adsorption mode of cinnamaldehyde. More importantly, the permeable characteristic of carbon layer which maintained the accessibility of reactants to the Pt sites, contributed to the higher conversion compared to Ga2O3@PtGa catalysts with traditional oxide interface layer. Additionally, C@PtGa catalyst exhibited a good reusability with conversion of 88.3% and selectivity of 91.9% after 5 cycles. This work provides an alternative way to realize the boost of activity and selectivity in selective hydrogenation of C=O bonds by intelligently fabricating non-oxides@metal interface.

A Schiff base of chitosan with cinnamaldehyde (Cinn-Cht) was synthesized in a single step using microwave irradiation and characterized using spectroscopic techniques. The synthesized Schiff base was used for the mitigation of carbon steel corrosion in 15% HCl. The corrosion evaluation was performed using weight loss tests, electrochemical impedance measurements, and polarization studies. The corrosion inhibition efficiency increased with inhibitor dosage and achieved a high value of 85.16% at 400 mgL−1. The inhibitor adsorption followed the Langmuir isotherm and displayed a mixed physical and chemical adsorption behavior. To further improve the corrosion inhibition efficiency, potassium iodide (KI) was incorporated in the corrosive solution, which increased the inhibition efficiency further to 92.45% at a concentration of 10 mM. Surface studies carried out via SEM analyses indicated the inhibitor adsorption and protective film formation on the steel surface. The computational studies carried out via DFT revealed that mainly the protonated form of inhibitor adsorbs on the metal surface. Monte Carlo simulation studies also showed that the protonated form of the inhibitor molecule exhibited higher adsorption energy than the neutral inhibitor.

The selective hydrogenation of cinnamaldehyde (CAL) is an extremely important transformation. Herein, oxygen functionalized carbon nanotubes (oCNTs) supported a series of PtxCoy bimetallic nanoparticles (NPs) with varied Pt to Co ratios were synthesized. The introduction of Co significantly affects the electronic structure of Pt NPs, which clearly promotes the selectivity to cinnamyl alcohol (COL). Among all PtxCoy-oCNTs catalysts, PtCo3-oCNTs exhibited the best catalytic performance and a selectivity of over 76% towards COL at a CAL conversion of 99% was obtained. Further characterization of the fresh, used and cycled catalysts revealed that the NP structures were stable and did no change. The structural evolutions during the catalytic reaction were also investigated by identical location transmission electron microscopy (IL-TEM) method in detail, which found that the deactivation of PtCo3-oCNTs catalyst during the cycle experiment results from the agglomeration and detachment of PtCo3 NPs.

The bimetallic core–shell nanostructures of galvanic metals have gained considerable scientific interest in improving the TiO2 photocatalysis under solar radiations over the monometallic analogues. In the present research work, Pd@Au core–shell supported TiO2 nanostructures were synthesized via galvanic replacement reaction and were examined for their catalytic/ photocatalytic hydrogenation. Three different types of bimetallic Pd@Au nanostructure were synthesized by varying Pd:Au weight ratio i.e. (1:1), (1:2) and (1:3). DLS measurements revealed that with increasing Au weight ratio, the hydrodynamic size increases from 126 to 157 nm. The optical studies showed a considerable blue shift in the absorption band of Au nanoparticles from 529 to 518 nm in the case of Pd@Au (1:1). The co-existence of absorption characteristic of Pd and Au suggests the successful synthesis of bimetallic nanostructure. STEM and EDS mapping further confirmed the formation of Pd@Au nanostructure with inner Pd core and outer Au shell. Bimetallic Pd@Au nanocatalyst displayed superior activity and selectivity towards hydrogenation of cinnamaldehyde in comparison to monometallic analogues. However, when Pd@Au nanostructures were impregnated on the surface of TiO2, a significant improvement in the hydrogenation reaction was observed under solar radiations relative to catalytic conditions. The photocatalytic performance of Pd@Au-TiO2 was found to be varied as a function of shell thickness and the optimized APT-2 (Pd1@Au2-TiO2) photocatalyst exhibited higher rate constant (2.3 × 10−1 h−1) for cinnamaldehyde hydrogenation. Hence, the plasmonic Pd@Au-TiO2 hetero-junction could be a promising greener photocatalyst for selective hydrogenation of unsaturated carbonyls for large scale industrial applications.

Ceria-zirconia oxide materials with a specific surface area ranging from 160 to 240 m2/g and different meso- and micropores ratio were obtained by a simple deposition-precipitation method with urea (DPU), which allows preparation of ceria-zirconia oxides directly in one-step while avoiding the formation of oxo-hydroxo species and further thermal treatment to obtain oxide phases. Moreover, a microwave-assisted DPU method allowed the decrease of the synthesis time from 24 to 3.5 h. The prepared samples were studied by TG-DTA, BET, N2 adsorption, XRD, SEM, and TEM methods. Pt-containing catalysts based on synthesized oxides have shown a high catalytic activity in selective hydrogenation of benzaldehyde, citral, and cinnamaldehyde at room temperature and atmospheric pressure.

HPZSM-5 with hierarchical porous structure obtained via partial desilication of commercial ZSM-5 was proved to be a suitable support for Pt nanoparticles towards the liquid-phase selective hydrogenation of cinnamaldehyde (CAL) to yield cinnamyl alcohol (COL). Compared with Pt/ZSM-5, Pt/HPZSM-5 showed improved catalytic performance although the improvement seems to be very limited. After doping Fe to Pt/HPZSM-5 with a Fe/Pt molar ratio of 0.25, the PtFe/HPZSM-5 catalyst gave much further enhanced CAL conversion. Under the optimized conditions, a 97.9% CAL conversion with 87.6% selectivity to COL was achieved with the PtFe/HPZSM-5 catalyst. The initial activity (in terms of TOF value, defined as molecules of CAL converted per surface atom of Pt per second) reached about 3.41 s−1 with the PtFe/HPZSM-5 catalyst, one of the highest values up to now to our best knowledge. Moreover, the PtFe/HPZSM-5 catalyst can be recycled for at least 9 times without obvious loss in activity or selectivity to COL. The effect of partial desilication and Fe doping on the catalytic performance of PtFe/HPZSM-5 was discussed based on the characterization results using a series of techniques.

We have synthesized two ionic liquids namely 1-hexyl-1,2,4-triazolium methanesulfonate and 1-hexyl-1,2,4-triazolium trifluoroacetate. We have carried out the reduction of various aldehydes and ketones by NaBH4 in the presence of the synthesized ionic liquids. Cinnamaldehyde and acetophenone are used for the optimization of the reaction condition. Reduction of different aldehydes and ketones were carried out and a good yield of product is obtained where the ionic liquid with anion methanesulfonate is used. In the case of ketones, ionic liquid 1-hexyl-1,2,4-triazolium trifluoroactetate gives a good yield.

Fe3O4 nanoparticles have got more attention in their application as catalyst. This research aims to utilize Fe3O4 as nanocatalyst in modifying of cinnamaldehyde compound. In this study, Fe3O4 nanoparticles were synthesized by co-precipitation method using Fe2+ and Fe3+ ions and characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results of the characterization supports that Fe3O4 nanoparticles were successfully synthesized. Afterward, Fe3O4 would be applied in modifying of cinnamaldehyde compound. The results of the reaction were analyzed its absorbance, functional group, and molecular weight using UV/Vis Spectrophotometry, FT-IR and GC-MS. From the results of the synthesis and characterization, one cinnamaldehyde modified compounds was obtained, namely 2-amino-4-styryl-4H-benzo[h]chromene-3-carbonitrile (Compound 1). From the yield of the reaction, a significant difference was found between the reaction with and without catalyst

CoxFe1-xAl2O4+δ composite oxides were prepared using a sol-gel method with glucose as hard template. Pt nanoparticles supported on CoxFe1-xAl2O4+δ were employed for the liquid-phase selective hydrogenation of cinnamaldehyde (CAL) to yield the desired cinnamyl alcohol (COL). The activity increased with the x value; while the selectivity to COL almost kept above 90% despite of different x values. Upon investigation of kinetic behaviour with Pt/Co0.5Fe0.5Al2O4+δ as a model catalyst, the initial activity (in terms of TOF, defined as the converted CAL molecules per surface Pt atoms per second) of 4.1 s−1 was furnished. As for the selectivity to COL, it almost kept around 95% at whatever CAL conversions despite of the reaction temperatures. Pt/Co0.5Fe0.5Al2O4+δ catalyst can also be recycled for at least 10 times without obvious loss in activity or selectivity toward COL. This suggests that the active sites on the Pt/Co0.5Fe0.5Al2O4+δ catalyst preferentially adsorb and activate CAL via the terminal carbonyl groups. XPS analyses, H2-TPR, and CO-IR studies reveal that the intimate contact of Pt nanoparticles with FeOx or CoOx plays an important role in determining the catalytic performance of the Pt/CoxFe1-xAl2O4+δ catalysts. The Pt δ+/Pt0 ratio increased with the x value so that the Pt/CoAl2O4 was the most active among the Pt/CoxFe1-xAl2O4+δ catalysts.

SUMMARY Oleum cinnamomi (OCM, cinnamon oil), which is produced by aromatic cinnamon plants, is increasingly used as a feed additive to animal diets. OCM is a natural product rich in polyphenolic compounds that exhibit strong antioxidative property. However, the direct addition of OCM to the feed is questionable due to several limiting physical–chemical factors such as the high hydrophobicity, volatility, odor, fast decomposition, and poor availability in the lower gastrointestinal tract of animals. Therefore, the coated form of OCM (cOCM) is one of the ways to solve these concerns. We have demonstrated that dietary cOCM supplementation did not improve the growth performance of broiler chickens, but it showed beneficial effects on immunity and intestinal integrity. In the current study, we further investigated the intestinal cinnamaldehyde release and antioxidative capacity of chickens fed cOCM-supplemented diets. As cinnamaldehyde is a major constituent of OCM, we evaluated the release of cOCM in the intestine of birds by determining the contents of cinnamaldehyde in the digesta of small intestine and cecum. The increased availability of OCM in the lower intestine supplied a foundation for exerting its antioxidative effects. The activities of antioxidative enzymes were increased and superoxide levels were decreased in the plasma and intestinal mucosa of birds fed cOCM-supplemented diets. The improvement of antioxidative capacity was achieved by modulating the gene expression of nuclear factor erythroid 2-related factor 2 and downstream antioxidative enzymes.

A mixed natural preservative, including grapefruit seed extract (GSE), cinnamaldehyde (CA), and nisin, was investigated for the reduction of Listeria monocytogenes growth on lettuce and raw pork loin. The MIC of each natural preservative was investigated for L. monocytogenes strains tested. Following central composite design, lettuce and pork loin were inoculated with a cocktail of three strains of L. monocytogenes (ATCC 15313, H7962, and NADC 2045 [Scott A]) and treated with the mixed natural preservative that included GSE (0.64 to 7.36 ppm), CA (1.6 to 18.4 ppm), and nisin (0.48 to 5.5 ppm). The MIC of GSE was 31.25 ppm in tested L. monocytogenes strains, and of CA was 500 and 1,000 ppm in L. monocytogenes ATCC 15313 and the other L. monocytogenes strains, respectively. The MIC of nisin was 250 ppm. The R2 value of this model was more than 0.9, and the lack of fit was not significant. The mixed natural preservative showed a synergistic antimicrobial effect and reduced the growth of L. monocytogenes by 4 to 5 log CFU/g on lettuce. In addition, the reduction of L. monocytogenes on pork loin was 3 log CFU/g. The mixed natural preservative, which consisted of GSE (6 to 8 ppm), CA (15 to 20 ppm), and nisin (5 to 6 ppm), increased the antibacterial effect against L. monocytogenes. These results suggest that the use of the mixed natural preservative could reduce the economic cost of food preparation, and response surface methodology is considered effective when measuring synergy among antimicrobials.

The surface chemistry of catalyst plays a vital role in the catalytic process. And the effects of surface groups of porous boron nitride (p-BN) on the hydrogenation reaction have not been studied in detailed. In this work, two main surface species of Co/p-BN catalyst were tuned thermally and their roles on the hydrogenation reaction were discriminated by α, β-unsaturated aldehyde hydrogenation reaction. The surface B O content decreased at higher reduction temperature and the cobalt phase changed from CoO to the mixture of CoO and Co0. The Co/p-BN-500 exhibited the highest selectivity to C O hydrogenation. And its turnover frequency (TOF) of 13.2 h−1 is close to the optimal value of reported cobalt catalysts. When the reaction proceeds, hydrogenation rate of C O increases but that of C C decreases gradually, thus a surface groups variation was expected at the initial period. Further in-situ FTIR spectra showed the band intensity of edge N H increases as the adsorption proceeds at 50°С but it decreases as the temperature rise to 200°С, in combined with the shift of C O adsorption peak, a intermolecular hydrogen bond between edge N H and the terminal C O group was suggested, which account for the better selectivity to C O than C C.

Objective Invasive pulmonary Aspergillus infection has the characteristics of high morbidity, difficult to be treated, poor prognosis and high mortality. This study aims to investigate the effects of cinnamaldehyde on 1,3-β- D -glucans in the pulmonary Aspergillus fumigatus cell wall to provide a basis for developing novel antifungal drugs. Methods Immunosuppressed ICR mice were intranasally inoculated with 50 µL of A. fumigatus suspension (1 × 107 CFU/mL) and then separated into two groups, for the experimental group cinnamaldehyde was orally administered at 240 mg/kg/d consecutively for 14 d. While for the control group, voriconazole was used to treat the fungus infection. Pulmonary tissues were then extracted for 1,3-β- D -glucans assay and electron microscopy. Results The concentration of 1,3-β- D -glucans was significantly different between the cinnamaldehyde and voriconazole groups, which was (1160.89 ± 364.96) pg/mL and (3885.94 ± 845.45) pg/mL, respectively (P D -glucan layer) of A. fumigatus cell wall were damaged and fell off, resulting in serious defect of the cell wall, but the cell membrane was clear and intact. Conclusion Cinnamaldehyde has a significant influence on the integrity of 1,3-β- D -glucans in the pulmonary A. fumigatus cell wall, but the cell membrane is unaffected, suggesting that cinnamaldehyde has unique antifungal properties depending on its action against the 1,3-β- D -glucans on the pulmonary A. fumigatus cell wall.

Antimicrobial products such as silver nanoparticles and QACs - Quaternary ammonium compounds, used to produce antibacterial textiles, are being targeted due to environmental concerns. Most of the active antibacterial molecules from essential oils are small molecules with a solubility parameter (δ) close to that of polyester –PET-poly(ethylene terephtalate) (δ=21.9 MPa1/2 at 129.4 °C), and can therefore be potentially used to functionalize polyester fabrics using diffusion process. The aim of this paper was to explore the diffusion process to produce antibacterial polyester textiles using active agent(s) from essential oils. Diffusion process was explored at high temperature (130 °C) and pressure, to functionalize polyester fabric (PET) with five different bio-based antimicrobial agents isolated from essential oils. Thymol, geraniol, cinnamaldehyde, ortho-vanillin and para-vanillin, were selected based on their solubility parameter (in the range of 19 to 25 MPa1/2), and small their molecular size (molecular weight Both quantitative and qualitative tests were used to analyze antibacterial activity of the functionalized polyester fabrics. Quantitative absorption method (ISO20743) showed that most of the functionalized polyester textiles exhibit antibacterial activity towards gram positive (Staphylococcus aureus) and gram negative (Klebsiella pneumoniae) bacteria, though no inhibition zone was observed with the qualitative agar diffusion method. Spectrophotometric analysis of the functionalized fabrics confirmed the diffusion of the active agents inside the PET fibers in between macromolecular chains, as PET fibers became pale yellow. Antibacterial polyester fabrics functionalized with O-vanillin and cinnamaldehyde exhibited good wash durability. Thermogravimetric analysis showed that most of the active agents (except thymol), have maximum stability temperature ( The toxicity issue is also discussed with the view of using the antibacterial polyester textiles for outdoor applications.

Graphene is an ideal model support to investigate the influence of carbon surface chemistry on catalytic reactions. Here a mild hydrothermal method was developed to synthesize graphene-supported iridium nanocatalysts from graphene oxide. By simply varying the hydrothermal conditions, the physicochemical properties of catalysts can be tuned, which can further affect their catalytic performances. Catalysts obtained at higher H2 pressure during hydrothermal process performed higher catalytic activities for hydrogenation of both p-chloronitrobenzene and cinnamaldehyde, benefiting from their higher reduction degrees of iridium nanoparticles. Interestingly, catalysts obtained at lower hydrothermal temperature performed higher activities for p-chloronitrobenzene hydrogenation but lower activities for cinnamaldehyde hydrogenation, due to their distinct surface chemistry of graphene. Through systematic characterizations on 11 catalysts prepared under various conditions, we found that lower hydrothermal temperature endows graphene with larger lateral dimension and more in-plane oxygenated surface groups, which facilitates the accessibility of nitro groups to catalyst surface via H-bond interaction as confirmed by density functional theory calculations. This is not true for cinnamaldehyde, of which adsorption on graphene via π-π stacking interaction is favorable for its hydrogenation.

Hypothesis Because of its hydrophilic character the peptide drug Polymyxin B (PMB) cannot be incorporated in lipophilic nanocarrier systems such as self-emulsifying drug delivery systems (SEDDS) for oral administration. Due to the formation of imine conjugates between the primary amino groups of PMB and the carbonyl group of cinnamaldehyde, however, drug lipophilicity might be sufficiently raised for incorporation in SEDDS. Methods Imine bonds were formed between the primary amino groups of PMB and the carbonyl group of cinnamaldehyde. PMB-cinnamaldehyde conjugate was characterized regarding degree of substitution, log P and release of PMB due to interaction with bovine serum albumin (BSA), SEDDS loading and cell viability. Results 87.1% of primary amines formed imines with cinnamaldehyde. Log P was increased 69.183 – folds. BSA triggered release of PMB was 45.2%, 64.9% and 80.6% within 16 h. Log DSEDDS/Release medium of PMB-cinnamaldehyde conjugate was 3.4. Conclusion According to these findings, the concept of imine bond formation with cinnamaldehyde can be considered as a novel concept for increasing lipophilicity of the hydrophilic antibiotic peptide PMB.

The water-dispersibility and antimicrobial activity of cinnamon oil is enhanced by encapsulating it within oil-in-water nanoemulsions. This study investigated the impact of oil phase composition on the minimum inhibitory concentration (MIC) of cinnamon oil nanoemulsions against Escherichia coli, Salmonella enterica serovar Typhimurium (S. Typhimurium), Staphylococcus aureus and Vibrio parahaemolyticus. The nanoemulsions were fabricated using the phase inversion temperature (PIT) method, which simply involves heating a mixture of surfactant, oil, and water about the PIT and then quench cooling with stirring. The antimicrobial activity of cinnamon oil is largely due to cinnamaldehyde, which is highly susceptible to chemical degradation. For this reason, the decrease in cinnamaldehyde content and increase in a major reaction product (benzaldehyde) were measured in the cinnamon oil nanoemulsions during storage. The antimicrobial activity of cinnamon oil nanoemulsions increased (lower MICs) as the droplet size decreased. Cinnamaldehyde was degraded during emulsification and after storage for 31 days. These results have important implications for the improvement of the antimicrobial activity and stability of encapsulated cinnamon oil using nanoemulsion-based delivery systems.

Aerobic selective oxidation of allylic aldehydes offers an atom and energy efficient route to unsaturated carboxylic acids, however suitable heterogeneous catalysts offering high selectivity and productivity have to date proved elusive. Herein, we demonstrate the direct aerobic oxidation of cinnamaldehyde to cinnamic acid employing silica supported Pt nanoparticles under base-free, batch and continuous flow operation. Surface and bulk characterisation of four families of related Pt/silica catalysts by XRD, XPS, HRTEM, CO chemisorption and N2 porosimetry evidence surface PtO2 as the common active site for cinnamaldehyde oxidation, with a common turnover frequency of 49,000 ± 600 h−1; competing cinnamaldehyde hydrogenolysis is favoured over metallic Pt. High area mesoporous (SBA-15 or KIT-6) and macroporous-mesoporous SBA-15 silicas confer significant rate and cinnamic acid yield enhancements versus low area fumed silica, due to superior platinum dispersion. High oxygen partial pressures and continuous flow operation stabilise PtO2 active sites against in-situ reduction and concomitant deactivation, further enhancing cinnamic acid productivity.

In present study, three kinds of sodium carboxymethyl cellulose (CMCNa) were used to modulate the stability of cinnamaldehyde-loaded liposomes at high ionic strength (0.66 mol/L). The effects of different types and concentrations of CMCNa on the physical properties of liposomes were characterized by rheological properties, appearance, distribution, microstructure, particle size and dispersion. Rheology measurements showed that CMCNa endowed viscoelasticity to liposomes. The molecular mass (Mw) and concentration of CMCNa were positively correlated to liposome stability. CMCNa with Mw 1,185,955 was the most effective for liposomes stability at concentrations of 0.8% and 1.0% (w/v). Transmission electron microscope (TEM) results showed that CMCNa-П formed an associated layer around liposomes. Steric hindrance between particles was attributed to the improvement of stability of liposomes. Dispersion analysis demonstrated 0.8% and 1.0% CMCNa-П had the better stability. These results may contribute to the development of stable liposomes with potential applications for bioactive molecules encapsulation and delivery.

In order to exploit multifunctional packaging material, soy protein isolate (SPI) based biocomposite films incorporated with plant-sourced cinnamaldehyde (CIN) and zinc oxide nanoparticles (ZnO NPs) synthesized by a liquid precipitation method were prepared and characterized. The functional actions between cinnamaldehyde and zinc oxide nanoparticles on the physical, mechanical and antifungal properties of the obtained film samples were subsequently investigated in this study. Results indicated that the addition of CIN produced a SPI composite film with low tensile strength (TS) and elongation at break (EAB), but these alterations were the opposite in SPI + ZnO film. Moreover, the incorporation of CIN or ZnO NPs to SPI matrix affected differently color parameters, oxygen permeability and storage modulus of the resulting composite films. Among regular SPI film and composite film with one added ingredient, SPI-based bionanocomposite film containing CIN and ZnO NPs displayed the best barrier capacities, mechanical properties and antifungal activities. Its values of tensile strength and breaking elongation are 1.26-fold and 1.23-fold than that in the pristine SPI film, respectively. Meanwhile, the oxygen permeability and water permeability for SPI + CIN + ZnO film are 66.1% and 54.8% of that in regular SPI film, respectively. Moreover, the antifungal activity of the composite film with two added ingredients is 1.56-fold and 1.24 fold stronger than those of SPI + ZnO and SPI + CIN films. These investigations reveal that the developed SPI + CIN + ZnO film could be utilized as an ideal packaging matrix for food preservation.

Inclusion complexes based on β-cyclodextrin (β-CD) and antimicrobial compounds, were prepared by co-precipitation method, and characterized by entrapment efficiency (EE), thermal analysis, X-ray diffraction, 1H NMR spectroscopy, and water sorption. In addition, experiments associated to evaluate the effect of relative humidity on the release of active compounds and antifungal tests were performed. The analysis evidenced the encapsulation of active compounds into the β-CD structure with EE of 91 ± 4.1% and 66 ± 2.1% for β-CD/cinnamaldehyde and β-CD/eugenol complexes, respectively. Additionally, high relative humidities favored the release of active compounds from inclusion complexes. On the other hand, inclusion complexes were able to control the growth of B. cinerea, which was evidenced by a reduction of its mycelialradial growth. Finally, specific interactions between the active compounds and β-CD were evaluated through molecular dynamics simulation techniques. According to the obtained results, these complexes could be applied as additives in the design of antifungal packaging.

Rheumatoid arthritis (RA) is an autoimmune disorder affecting joints and frequently characterized by initial local and later systemic inflammation. The present study was conducted with the aim to determine the anti-inflammatory and antioxidant effects of cinnamaldehyde and eugenol in the peripheral blood mononuclear cells (PBMC) of RA patients. PBMCs obtained from RA patients were treated with varying concentrations of cinnamaldehyde and eugenol. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were monitored in the 24-h culture supernatant of PBMCs. Reactive oxygen species formation, biomolecular oxidation and the activities of antioxidant enzymes were also determined. FTIR analysis was done to determine structural alterations in the PBMCs. Molecular docking was performed to gain an insight into the binding mechanism of eugenol and cinnamaldehyde with pro-inflammatory cytokines. The levels of pro-inflammatory cytokines and markers of oxidative stress were found to be elevated in the PBMC culture of RA patients as compared to the healthy controls. Cinnamaldehyde and eugenol have significantly reduced the levels of cytokines. Reactive oxygen species formation, biomolecular oxidation and antioxidant defense response were also ameliorated by treating PBMCs with both the compounds. FTIR results further confirms cinnamaldehyde and eugenol mediated protection to biomolecules of PBMCs of RA patients. Molecular docking results indicates interaction of cinnamaldehyde and eugenol with key residues of TNF-α and IL-6. Cinnamaldehyde and eugenol were found to exert potent anti-inflammatory and anti-oxidant effects on the PBMC culture of RA patients. So, these compounds may be used as an adjunct in the management of RA.

As a natural preservative, cinnamaldehyde (CA) has a bright application prospect. However, CA is sensitive to light and can be easily oxidized. What's more, its water solubility is poor. These properties greatly limit its application. In this study, CA/sodium alginate (SA)/chitosan (CS) nanoparticles (CA/SA/CS NPs) were prepared by using SA and CS as wall materials, and CA as core material. The single factor experiment showed that the optimal CA/SA/CS NPs can be obtained when the mass ratio of SA to CS was 5.5/1, SA to CaCl2 was 5/1, SA to CA was 1/2, and the pH of CS solution was 5.0. Under this condition, the average size of the prepared nanoparticles was 455.2 nm, polymer dispersity index (PDI) value was 0.189, zeta potential was −40.8 mV, and the encapsulation efficiency was 72.92%. The scanning electron microscopy (SEM) and atomic force microscopy (AFM) images confirmed the formation of nanoparticles, which were spherical or ellipsoidal in shape. The fourier transform infrared spectroscopy (FTIR) and multifunctional polycrystalline X-ray diffraction (XRD) spectra indicated that CA was encapsulated in the nanoparticles. Furthermore, in vitro release experiments showed that CA/SA/CS NPs had the function of sustained release. In summary, SA/CS NPs can be used as a promising carrier for CA.

The aim of this work is to investigate the effect of active compound kinetics on biofilm inhibition and quorum quenching in chicken meat. The results showed that 20–40 g/100 mL of exopolysaccharide inhibition can be achieved through treatment of particle size reduced S. aromaticum and C. cassia in P. aeruginosa. Inhibition of AHL molecules in P. aeruginosa exhibits the quorum quenching potentials of particle size reduced S. aromaticum and C. cassia. Application of spice fused edible films over chicken meat was found to inhibit its microbiota, through diffusion of cinnamaldehyde and eugenol at the rate of 0.79 × 10−15 ± 0.02 × 10−15 and 0.75 × 10−10 ± 0.03 × 10−10 cm2/s, respectively. Antimicrobial and AHL inhibition capabilities of spices were found to be the major contributors for shelf life extension of chicken meat. Particle size reduced S. aromaticum and C. cassia was found to be effective in control of lipid and protein oxidation in chicken meat stored at 4 °C.

BN-supported Pt catalysts were prepared by an impregnation method using Pt(NH3)4(NO3)2 as metal precursors and tested in the liquid-phase selective hydrogenation of cinnamaldehyde. It was found that the Pt/BN catalyst exhibited a high performance for the selective C O hydrogenation at room temperature. A selectivity of over 85% towards cinnamyl alcohol at a cinnamaldehyde conversion of over 95% could be obtained. The effects of supports and Pt particle sizes were explored by N2 physisorption, XRD, TEM, HRTEM, HAADF-STEM, TPD, H2-TPR, XPS, CO-DRIFTS, etc. The influences of solvents and operation conditions were investigated, and a simplified kinetics test was also carried out. The comparison of different supports suggested that BN with an inert surface and few acid-base sites possibly favors a simple adsorption mode of cinnamaldehyde dependent only on the supported Pt particles, resulting in a high selectivity to cinnamyl alcohol. While the abundant acid-base surface sites on the Pt/Al2O3 or Pt/SiO2, possibly associated with the multiple adsorption modes of cinnamaldehyde, had an adverse effect on the selective C O hydrogenation. The investigation of Pt size effect showed that large Pt particles with few low coordinated Pt sites displayed a higher selectivity to cinnamyl alcohol than small Pt particles with more low coordinated Pt sites on the Pt/BN catalysts. It was also revealed that water is a suitable solvent, and the presence of water in a mixture solvent is crucial for achieving a high activity of the Pt/BN in cinnamaldehyde hydrogenation.

A novel semicarbazone, α‒methyl trans cinnamaldehyde semicarbazone has been synthesized and characterized by elemental analysis, FT-IR, FT-Raman, NMR and UV-Visible spectral techniques. The single crystal X-ray diffraction study of the isolated crystals of the compound reveals that the compound crystallizes in triclinic Pī space group with cell dimensions a = 7.1821(4) A, b = 14.9090(13) A, c = 16.1096(11) A, α = 84.496(4)°, β = 79.046(3)° and γ = 80.758(3)°. The thermal stability of the compound was investigated by thermogravimetry. The DFT calculations of the title compound were performed by B3LYP 6‒31++G (d,p) level of theory by using Gaussian 09 programme.

A wettability-controllable surface on carbon nanotubes (CNTs) was successfully constructed through directly grafting poly(N-isopropylacrylamide) (PNIPAM) from CNT surface (i.e. CNT-PNIPAM) via a facile method. The hybrid was employed as the support to prepare Pd catalyst (i.e. Pd/CNT-PNIPAM) for selective hydrogenation of cinnamaldehyde (CAL). The effects of thermoresponsive surface chemistry on catalytic performance were studied. Results showed that CNT-PNIPAM had the lower critical solution temperature (LCST) at about 37 °C. The hydrophilic surface of CNT-PNIPAM at 25 °C ( LCST), which exhibited the good adsorption properties for reactants in the reaction. The high Pd dispersion on Pd/CNT-PNIPAM as well as its good adsorption properties for CAL jointly resulted in an enhanced catalytic activity, meanwhile maintaining the selectivity to cinnamyl alcohol (COL) unchanged in comparison to CNT supported Pd catalyst (Pd/CNT).

Gum karaya (GK) is an inexpensive and abundant source of polysaccharides in tropical countries. GK can be used for biodegradable film preparation without further extraction. In this study, active GK nanocomposite films containing Cloisite Na+ (CLS) and cinnamaldehyde (CIN) were developed. The physical properties of the GK films were examined. The dispersion of GK (2.5%, w/v) and glycerol (55% of gum, w/w) exhibited film-forming capacity. Addition of CLS enhanced the physical properties of the films by the intercalation of GK molecules into the layered structure of CLS nanoparticles. This structure was elucidated in the X-ray diffraction pattern of the GK nanocomposite films. In particular, the tensile strength of the GK film containing 11% CLS was increased by 73%, compared to that of the GK film without CLS. Water solubility and water vapor permeability of the GK films were decreased with the addition of CLS. Moreover, the incorporation of 0.25%, 0.50%, and 0.75% CIN caused the increase in elongation at break of the GK film containing 11% CLS by 60%, 82%, and 43%, respectively. Furthermore, the addition of CLS and CIN increased the opacity of the GK films. The GK film containing 11% CLS and 0.75% CIN exhibited antimicrobial activities against the tested pathogens. Thus, the results in this study suggest that the GK/CLS nanocomposite films containing CIN can be applied as an active packaging material.

Corn starch-based films containing cinnamon essential oil were prepared. The physical properties of the films, and the diffusion kinetics of cinnamaldehyde were analyzed. The results showed that the antibacterial polymer film containing 2.0% (w/v) cinnamon essential oil had the acceptable physical properties with the tensile strength and the elongation at break of 22.53 ± 0.16 MPa and 20.07 ± 1.18%, respectively. The diffusion kinetics of cinnamaldehyde followed Fick's diffusion law. The diffusion percentage of cinnamaldehyde into 10% ethanol was lower than that of 95% ethanol. For short-term diffusion into 95% ethanol, the estimated n-values were between 0.1736 and 0.3519 and the diffusion coefficient (Dp) was increased with the increase of temperature. For long-term diffusion into 95% ethanol, the Dp values were decreased by 105–106 times in relative to short-term diffusion, and the partition coefficient (KP,F) was decreased with the increase of temperature. The antibacterial polymer film containing 2.0% cinnamon essential oil exhibited antibacterial activity for over 120 days.

A multifunctional photocatalyst is constructed based on Cu-Cu2O hybrid and monolayer H1.4Ti1.65O4·H2O nanosheets via an in situ photo-deposition process (Cu-Cu2O/TNS). The prepared sample enables the oxidation of cinnamyl alcohol to cinnamaldehyde with over 95% of selectivity under visible light irradiation using molecule O2 as the oxidant. In situ FTIR spectra suggest that the Lewis acid sites in TNS would selectively adsorbed the hydroxyl of cinnamyl alcohol forming surface C O∙∙∙Ti O coordination species. UV-DRS spectra reveal that light adsorption of TNS can be extended to visible light region due to the interface charges transfer from C OH to Ti O via the surface coordination, resulting in the activation of OH in alcohol. In situ ESR further indicates that directional interface charge transfer induces the charge enrichment in Ti atoms of TiO6, facilitating O2 adsorption. XAFS results reveal that the hybrid electronic states of Cu-Cu2O efficiently improve the interface electronic transfer kinetics to inhibit the intramolecular hydrogen transfer for dominating the selectivity towards cinnamaldehyde. This work highlights the synergistic effect of surface coordination-activation-photocatalysis for selective photosynthesis of fine chemicals.

Corrosion of copper has gained substantial attention due to its significant impact on the performance and reliability of metal in various applications. The process also makes the application of metal capital-intensive. In this work, a new approach was achieved by mixing two biologically extracted corrosion inhibitors (Cinnamaldehyde (C9H8O) and Vanillin (C8H8O3)) in acid solution to protect copper surface from corrosion. The inhibitors are environmentally friendly and can cover up to 98.36% of the metal’s surface, thus significantly reducing the corrosion rate. Molecular dynamic simulation on inhibitor films shows that the synergistic inhibitory effect is enhanced due to the reasons that: (1) the new inhibitor films are denser at the surface due to the filling of C8H8O3 into the voids of C9H8O and (2) the new inhibitor films are more stable and the diffusion coefficients of inhibitor molecules approximately are 1–2 × 10−4 cm2 s-1. The results from this study could contribute to better understanding of the synergistic mechanism of the two corrosion inhibitors, which could in turn help in developing novel inhibitors in future.

Background Oxidative stress contributes to the pathogenesis of many human diseases. Cinnamon is a worldwide used spice, dietary supplement and traditional medicine, and is used for the therapy of oxidative stress related diseases. A well-established concept is that the functions of cinnamon preventing oxidative stress-induced diseases are attributed to the occurrence of cinnamaldehyde and its analogues. Hypothesis In our continuous searching of natural molecules with antioxidant capacity, we have found that cinnamaldehyde and its analogues in cinnamon are weak inhibitors of oxidative stress, and thus we speculate that there are novel and/or potent molecules inhibiting oxidative stress in cinnamon. Study design and methods A systemic phytochemical investigation of cinnamon using column chromatography was performed to identify the chemical constituents of cinnamon, and then their capacity of inhibiting oxidative stress and action of mechanism targeting Nrf2 pathway were investigated using diverse bioassay, including NAD(P)H: quinone reductase (QR) assay, immunoblot analysis, luciferase reporter gene assay, immunofluorescence and flow cytometry. Results Cinnamon improved the intracellular antioxidant capacity. A systemic phytochemical investigation of cinnamon gave the isolation of twenty-two chemical ingredients. The purified constituents were tested for their potential inhibitory effects against oxidative stress. Besides cinnamaldehyde analogues, a lignan pinoresinol (PRO) and a flavonol (-)-(2R,3R)-5,7-dimethoxy-3′, 4′-methylenedioxy-flavan-3-ol (MFO) were firstly identified to be inhibitors of oxidative stress. Further study indicated that PRO and MFO activated Nrf2-mediated antioxidant response, and protected human lung epithelial cells against sodium arsenite [As(III)]-induced oxidative insults. Conclusion The lignan PRO and the flavonoid MFO are two novel Nrf2 activators protecting tissues against oxidative insults, and these two constituents support the application of cinnamon as an agent against oxidative stress related diseases.

In the present work, a series of Pt-based catalysts, alloyed with a second metal, i.e., Re, Sn, Er, La, and Y, and supported on activated carbon, ordered mesoporous carbon, N-doped mesoporous carbon or reduced graphene oxide (rGO), have been developed for selective hydrogenation of cinnamaldehyde to cinnamylalcohol. Re and rGO were proved to be the most favorable metal dopant and catalyst support, respectively. Pt50Re50/rGO showed the highest cinnamylalcohol selectivity of 89% with 94% conversion of cinnamaldehyde at the reaction conditions of 120 °C, 2.0 MPa H2 and 4 h.