The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogou...The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogous to the"Transformers",which can transform into benzofurans and benzaldehydes via annulation reactions.Under the synthetic standpoint,this deconstructive reorganization strategy features high atom economy,innate scalability and functional group tolerance.In the near future,we believe that this unique method will be widely investigated a nd other novel transformations of kojic acid and maltol will be discovered.展开更多
[Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematica...[Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematical model of uncertainty was established by analyzing the method for determining ethyl maltol using UPLC-MS.The sources of uncertainty were analyzed,and the components of uncertainty were calculated to evaluate the expanded uncertainty of the method.[Results]When the content of ethyl maltol in edible vegetable oil was 1657μg/kg,the expanded uncertainty was 22.4μg/kg(K=2,P=95%).[Conclusions]The uncertainty in this evaluation model mainly came from standard solution preparation,sample weighing,dilution of sample to constant volume,standard curve fitting,and repeated measurement.展开更多
The high-resolution X-ray structure of the adduct formed upon the reaction of hen egg white lysozyme(HEWL)with the potential drug BMOV(bis(maltolato)oxidovanadium(Ⅳ)or[V^(Ⅳ)O(malt)_(2)],where malt=maltolato)from cry...The high-resolution X-ray structure of the adduct formed upon the reaction of hen egg white lysozyme(HEWL)with the potential drug BMOV(bis(maltolato)oxidovanadium(Ⅳ)or[V^(Ⅳ)O(malt)_(2)],where malt=maltolato)from crystals grown in 1.1 M NaCl and 0.1 M sodium acetate at pH 4.0 reveals an unexpected reaction product,where the V compound is transformed,the maltolate ring is broken and a significant modification of the N-terminal lysine side chain is observed.The results,also supported by gel electrophoresis and mass spectrometry data,show an unusual reactivity of BMOV with HEWL in the solid state,prompting further research on the reactivity of vanadium compounds with proteins which could depend on the specific experimental conditions.展开更多
Poly(lactic acid)(PLA)has limited promise as a bio-based antimicrobial packaging material due to its lack of plasticization,which limits antimicrobial agent release and antimicrobial efficiency.PLA were plasticized wi...Poly(lactic acid)(PLA)has limited promise as a bio-based antimicrobial packaging material due to its lack of plasticization,which limits antimicrobial agent release and antimicrobial efficiency.PLA were plasticized with polyethylene glycol(PEG)and blended with ethyl maltol or ethylenediaminetetraacetic acid(EDTA)as antibacterial agents by melt extrusion.The effects of combining PEG,EDTA,and ethyl maltol on sheet properties and antibacterial activity were investigated.Incorporation of ethyl maltol created a dense and smooth homogeneous surface,while EDTA addition caused large pores in the PLA sheet microstructure impacting swelling degree,water solubility and surface hydrophilicity.Fourier transform infrared(FTIR)spectroscopy and differential scanning calorimetry(DSC)showed that both ethyl maltol and EDTA addition modified the amorphous and crystalline phases of plasticized PLA.FTIR results suggested interaction between the functional groups of PLA chains,PEG,ethyl maltol or EDTA which affected the glass transition temperature(T_(g)),degree of crystallinity,and thermal stability of PLA.Adding PEG into PLA-EDTA enhanced antibacterial activity against Gram-positive Staphylococcus aureus(reduction of 1.35 log CFU/mL from the initial inoculum).The higher water solubility of sheets corresponded to a suitable release rate and sufficient amounts of antimicrobial compounds against Staphylococcus aureus.In vitro antifungal testing,PLA-PEG-EDTA sheets did not exhibit a clear zone of inhibition but delayed Penicillium sp.spore formation until day 5 of incubation.PEG plasticized PLA sheets functionalized with ethyl maltol and EDTA showed potential as active biomaterials against food-borne pathogen bacteria Staphylococcus aureus.展开更多
基金the National Natural Science Foundation of China(Nos.21871053 and 21532001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)。
文摘The deconstructive reorganization strategy for the synthesis of benzene-containing products from the kojic acid-and maltol-derived alkynes has been recently reported.In this strategy,kojic acid and maltol are analogous to the"Transformers",which can transform into benzofurans and benzaldehydes via annulation reactions.Under the synthetic standpoint,this deconstructive reorganization strategy features high atom economy,innate scalability and functional group tolerance.In the near future,we believe that this unique method will be widely investigated a nd other novel transformations of kojic acid and maltol will be discovered.
文摘[Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematical model of uncertainty was established by analyzing the method for determining ethyl maltol using UPLC-MS.The sources of uncertainty were analyzed,and the components of uncertainty were calculated to evaluate the expanded uncertainty of the method.[Results]When the content of ethyl maltol in edible vegetable oil was 1657μg/kg,the expanded uncertainty was 22.4μg/kg(K=2,P=95%).[Conclusions]The uncertainty in this evaluation model mainly came from standard solution preparation,sample weighing,dilution of sample to constant volume,standard curve fitting,and repeated measurement.
基金Elettra staff for their assistance during data collection.A.Merlino thanks MIUR PRIN 2022-Cod.2022JMFC3X,“Protein Metalation by Anticancer Metal-based Drugs”for financial supportE.G.thanks Fondazione di Sardegna(grant FdS2017Garribba)for the financial support.
文摘The high-resolution X-ray structure of the adduct formed upon the reaction of hen egg white lysozyme(HEWL)with the potential drug BMOV(bis(maltolato)oxidovanadium(Ⅳ)or[V^(Ⅳ)O(malt)_(2)],where malt=maltolato)from crystals grown in 1.1 M NaCl and 0.1 M sodium acetate at pH 4.0 reveals an unexpected reaction product,where the V compound is transformed,the maltolate ring is broken and a significant modification of the N-terminal lysine side chain is observed.The results,also supported by gel electrophoresis and mass spectrometry data,show an unusual reactivity of BMOV with HEWL in the solid state,prompting further research on the reactivity of vanadium compounds with proteins which could depend on the specific experimental conditions.
基金supported by Kasetsart University Research and Development Institute(KURDI),Kasetsart University,Thailand,FF(KU)5.67.
文摘Poly(lactic acid)(PLA)has limited promise as a bio-based antimicrobial packaging material due to its lack of plasticization,which limits antimicrobial agent release and antimicrobial efficiency.PLA were plasticized with polyethylene glycol(PEG)and blended with ethyl maltol or ethylenediaminetetraacetic acid(EDTA)as antibacterial agents by melt extrusion.The effects of combining PEG,EDTA,and ethyl maltol on sheet properties and antibacterial activity were investigated.Incorporation of ethyl maltol created a dense and smooth homogeneous surface,while EDTA addition caused large pores in the PLA sheet microstructure impacting swelling degree,water solubility and surface hydrophilicity.Fourier transform infrared(FTIR)spectroscopy and differential scanning calorimetry(DSC)showed that both ethyl maltol and EDTA addition modified the amorphous and crystalline phases of plasticized PLA.FTIR results suggested interaction between the functional groups of PLA chains,PEG,ethyl maltol or EDTA which affected the glass transition temperature(T_(g)),degree of crystallinity,and thermal stability of PLA.Adding PEG into PLA-EDTA enhanced antibacterial activity against Gram-positive Staphylococcus aureus(reduction of 1.35 log CFU/mL from the initial inoculum).The higher water solubility of sheets corresponded to a suitable release rate and sufficient amounts of antimicrobial compounds against Staphylococcus aureus.In vitro antifungal testing,PLA-PEG-EDTA sheets did not exhibit a clear zone of inhibition but delayed Penicillium sp.spore formation until day 5 of incubation.PEG plasticized PLA sheets functionalized with ethyl maltol and EDTA showed potential as active biomaterials against food-borne pathogen bacteria Staphylococcus aureus.
