Plant polyphenols are potential substitutes for clinicalα-glucosidase inhibitors.Our previous studies indicated that prodelphinidins from Chinese bayberry leaves(BLPs)have strongerα-glucosidase inhibitory activity t...Plant polyphenols are potential substitutes for clinicalα-glucosidase inhibitors.Our previous studies indicated that prodelphinidins from Chinese bayberry leaves(BLPs)have strongerα-glucosidase inhibitory activity than other common polyphenols,but they have no safe history of consumption.There is a reasonable prospect that prodelphinidins from Chinese bayberry fruits(BFPs)can improve postprandial hyperglycemia,though known active components are only myricetin and cyanidin-3-O-glucoside.Hence,the aim of this study was to analyze structure and hypoglycemic effect of BFPs of“Biqi”(BQPs)and“Dongkui”(DKPs)cultivars,and compare their difference with BLPs.The contents of BQPs and DKPs were(221.73±0.60)and(136.82±4.33)mg epicatechin(EC)equivalents/g dry weight,respectively.The most subunits were epigallocatechin gallate along with a small amount of epigallocatechin,epicatechin gallate and EC connected by B-type linkages and a small portion of A-type linkages with mean polymerization degree of 4.25 and 4.08,respectively.Importantly,BQPs and DKPs wereα-glucosidase inhibitors with half inhibitory concentration of 11.91 and 9.47μg/m L respectively,which were significantly stronger than BLPs.DKPs could also improve postprandial hyperglycemia of normal mice and high fat diet-induced type II diabetic mice.Therefore,edible prodelphinidins,which have stronger hypoglycemic effect than BLPs,were first found in Chinese bayberry fruits.展开更多
Latent fingerprints（LFPs） are the major physical evidences for the identification of individuals during crime spot investigation. Till date, numerous methods were followed to visualize LFPs. However, simple,accurate...Latent fingerprints（LFPs） are the major physical evidences for the identification of individuals during crime spot investigation. Till date, numerous methods were followed to visualize LFPs. However, simple,accurate, and cost-effective method has wide scope in advanced forensic field. In our work, Ca2 SiO4：Dy^（3＋）nanopowders（NPs） were fabricated via solution combustion route. The optimized sample was employed for the visualization of overlapped LFPs by the cost effective powder dusting method. The obtained results reveals the complete three levels of ridge characteristics with high sensitivity, reproducibility,selectivity, and reliability on various complex surfaces. The photoluminescence（PL） spectra consist of intense peaks at ～ 480 and 574 nm owing to ~4 F（9/2） →~6 H（15/2） and ~4 F（9/2）→~6 H（13/2） 4 f transitions of Dy3＋ ions,respectively. The photometric properties confirm that the samples exhibit intense white emission with high color purity. Therefore, the prepared NPs could be a definitive choice as an advanced luminescent NPs for forensic, solid state lighting and portable FED devices.展开更多
Objectives:The purpose of this study was to evaluate the antibrowning functions of hawthorn leaf extract on fresh-cut potato and its possible mechanism.Materials and Methods:Fresh-cut potatoes were treated with differ...Objectives:The purpose of this study was to evaluate the antibrowning functions of hawthorn leaf extract on fresh-cut potato and its possible mechanism.Materials and Methods:Fresh-cut potatoes were treated with different concentrations(0.01%,0.05%,and 0.1%)of hawthorn leaf extract and preserved at 4 C for 8 days.The appears nee and colour of potato slices were evaluated,along with the content of the phenol,malondialdehyde(MDA),and hydrogen peroxide(H2O2)during cold storage.Meanwhile,the activities of polyphenol oxidase(PPO),peroxidase(POD),phenylalanine ammonia-lyase(PAL),lipoxygenase(LOX),catalase(CAT),superoxide dismutase(SOD),and the antioxidant capacity were determ in ed.Furthermore,the composition of hawthorn leaf extract was analyzed by high-performance liquid chromatographytandem mass spectrometry(HPLC-MS/MS).Results:The addition of hawthorn leaf extract effectively delayed the browning process.It not only enhanced the CAT activity and antioxidant capacity but also reduced the LOX activity and accumulation of MDA and H_(2)O_(2).Meanwhile,the activities of PPO,POD,and PAL as well as the content of phe nol were con trolled.Additionally,25 phe nols,34 flavonoids,and 5 proa nthocya nidins were identified through high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),ideluding caffeic acid,quercetin and catechol.Conelusion:Hawthorn leaf extract significantly alleviated the browning of fresh-cut potato.It could serve as a n atural an tibrowning alter native by stabilizing the membra ne and modulating reactive oxygen species and redox reactions.展开更多
A light-promoted metal-free protocol for the amination of imidazo[1,2-a]pyridines with N-aminopyridinium salt by the assistance of surfactants in water was reported,charactering mild and environmentally benign conditi...A light-promoted metal-free protocol for the amination of imidazo[1,2-a]pyridines with N-aminopyridinium salt by the assistance of surfactants in water was reported,charactering mild and environmentally benign conditions,as well as great functional group tolerance.Micelles with negatively charged polar surface and hydrophobic core formed from sodium dodecyl sulfate serve as an ideal medium for visible-light mediated radical reaction of cationic pyridine salt and imidazo[1,2-a]pyridine in aqueous phase.The electrostatic interaction between positively charged N-aminopyridinium and negatively charged surface of micelles is of great significance in this method.展开更多
Objectives:Optimization of ultrasonic-assisted freezing of Penaeus chinensis by response surface methodology was studied in order to(1)obtain frozen Penaeus chinensis of high quality and(2)provide practical guidance f...Objectives:Optimization of ultrasonic-assisted freezing of Penaeus chinensis by response surface methodology was studied in order to(1)obtain frozen Penaeus chinensis of high quality and(2)provide practical guidance for the application of ultrasonic-assisted freezing in Penaeus chinensis.Materials and Methods:Three independent and major variables were selected,including initial ultrasonic temperature(℃),ultrasonic power(W)and ultrasonic time(s on/2 s off).On the basis of one-factor experiments,17 groups of experiments were established by response surface methodology according to Box-Behnken design.Using multiple regression analysis the experimental data were fitted into a second-order polynomial equation,which was tested by proper statistical methods.Results:The optimal ultrasonic conditions were as follows:initial ultrasonic temperature 0℃,ultrasonic power 180 W,ultrasonic time 5 son/2 s off.Under the optimization conditions,the time of passing through maximum ice crystal generation zone was 105.500 s,which was very close to the predictive passage time of 101.541 s.Conclusions:Initial ultrasonic temperature,ultrasonic time and ultrasonic power played an important role in the process of ultrasonic-assisted freezing of Penaeus chinensis.Response surface methodology was used to optimize the three factors in ultrasonic-assisted freezing,which could greatly shorten the time of passing through the maximum ice crystal generation zone and maintain the tissue structure of Penaeus chinensis well.展开更多
Probiotic fermented fruit juice could improve intestinal health with better sensory attributes.The effects of fermentation conditions on flavor quality of fermented bayberry juice were compared through microbial viabi...Probiotic fermented fruit juice could improve intestinal health with better sensory attributes.The effects of fermentation conditions on flavor quality of fermented bayberry juice were compared through microbial viability and sensory evaluation.Fermentation by combined Streptococcus thermophilus(ST)and Lactobaillus acidophilus(L A)resulted in higher microbial viability and sensory evaluation scores.The fermentation con-ditions were optimized by orthogonal experimental design and Technique for Order Preference by Similarity to an Ildeal Solution analysis(ST and LA in a mass ratio of 3:1;0.6%(mass concentration)inoculation;fermentation time,48 h,at 37℃;10%(mass concentration)added sucrose).Fermentation under these conditions decreased the anthocyanin content of the juice,maintained the total phenolic content,and slightly de-creased the antioxidant capacity.Fermentation reduced aroma volatiles from 42 in fresh juice to 33,as determined by gas chromatography-mass spectrometry-olfactometry(GC-MS-O),the aldehyde content decreased and the alcohol content increased.Lactic acid fermented bayberry juice by ST and LA produced a beverage with desirable consumer attributes,combining the health benefits of fresh juice and probiotics.展开更多
Acid-stable and highly active catalysts for the electrocatalytic oxygen evolution reaction(OER)are paramount to the advancement of electrochemical technologies for clean energy conversion and utilization.In this work,...Acid-stable and highly active catalysts for the electrocatalytic oxygen evolution reaction(OER)are paramount to the advancement of electrochemical technologies for clean energy conversion and utilization.In this work,based on the density functional theory(DFT)calculations,we systematically investigated the MSb_(2)O_(6)(M=Fe,Co,and Ni)and transition metal(TM)doped MSb_(2)O_(6)(TM-MSb_(2)O_(6),TM=Mn,Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,Ir,and Pt)as potential antimonate-based electrocatalysts for the OER.The stability and OER activity of these considered electrocatalysts were systematically studied under acidic conditions.It was found that Rh-NiSb_(2)O_(6),Pt-CoSb_(2)O_(6),Rh-FeSbO4,and Co-NiSb_(2)O_(6)can serve as efficient and stable OER electrocatalysts,and their OER catalytic activities are better than that of the current state-of-the-art OER catalyst(IrO2).Our findings highlight a family of promising antimonate-based OER electrocatalysts for future experimental verification.展开更多
Objectives:The bacteriostatic effects of a citral nanoemulsion against Shewanella putrefaciens CN-32(SHP CN-32)were investigated using in vitro culture and gene expression analysis,forbuilding a potential application ...Objectives:The bacteriostatic effects of a citral nanoemulsion against Shewanella putrefaciens CN-32(SHP CN-32)were investigated using in vitro culture and gene expression analysis,forbuilding a potential application in spoilage microorganism control and aquatic products quality maintenance.Materials and Methods:SHP CN-32 was treated by prepared citral nanoemulsion when the minimal inhibitory concentration(MIC)was verified.The growth curve,membrane integrity,scanning electron microscope(SEM)observation,biofilm formation and quorum sensing(QS)signaling molecule Al-2 content were evaluated in different MIC treatment groups(0 to 1.00 MIC).The gene expression status of SHP CN-32 in O and 0.50 MIC groups were compared using transcriptome sequencing and quantitative polymerase chain reaction(PCR).Results:The in vitro culture revealed that the citral nanoemulsion could inhibit the growth of SHP CN-32 with MIC of approximately 200μg/mL.Images of membrane integrity.SEM and biofilm formation suggested significant biological structure damage in bacteria after treatment.Meanwhile,the Qs signaling molecule Al-2 content showed a decline with increasing treatment concentration.Transcriptome sequencing and quantitative PCR revealed that the majority genes related diversified functional metabolic pathways of SHP CN-32 were downregulated at varying degree.Conclusion:A significant bacteriostasis of citral nanoemulsion against SHP CN-32 was verified via the results of growth inhibition,structural destruction,signal molecular decrease and gene expression downregulation of strains.These synergies significantly affect the characteristic expression of SHP CN-32,revealing the application potential as bacteriostat,QS inhibitor and preservative in aquatic products.展开更多
Fruit stored in poor conditions undergo biochemical degradations that impact fruit physical qualities,such color and firmness,and reduce beneficial nutritional content including vitamins,flavonoids,phenols,and antioxi...Fruit stored in poor conditions undergo biochemical degradations that impact fruit physical qualities,such color and firmness,and reduce beneficial nutritional content including vitamins,flavonoids,phenols,and antioxidants.This study investigated the impact of a postharvest treatment of mandarins with edible coatings to prevent biochemical degradations and minimize color changes.The edible coating evaluated in this study is a composite of pregelatinized corn starch(PS),with a cellulose nano fiber(CF)Pickering emulsifier,and is enriched with basil essential oil(EO).The results of varying each parameter were then analyzed by the Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS)method to identify the best-performing edible coating.Using this method,the leading edible coating was identified as PS5EO3 formulized from 5%pregelatinized corn starch,3%basil essential oil and 0.5%cellulose nanofiber,with a ranking of 0.721 based on quality content,and 0.676 based on percentage change in nutrients after the 12 days of storage at 25℃.Mandarins coated with PS5EO3 significantly suppressed quality losses,and achieving the lowest losses of citric acid(10.45%),while maintaining color stability in terms of color density(14.97%)and percent polymer color(78.14%).展开更多
The degradation of flavonoids helps to elucidate the mechanism of their biological activity,thus guiding individuals to better ingestion and utilization of these compounds.In this study,seven kinds of flavonoids with ...The degradation of flavonoids helps to elucidate the mechanism of their biological activity,thus guiding individuals to better ingestion and utilization of these compounds.In this study,seven kinds of flavonoids with typical structures were in vitro fermented by fresh feces,and the degradation process of flavonoids were monitored by HPLC,and the gut microbiota constitutes were analyzed by 16 S rRNA microbiota sequencing.Results indicated that all seven kinds of flavonoids could be degraded by intestinal microbiota.In addition,the degradation products of flavonoids showed excellent antioxidant and anti-inflammatory activity,especially the degradation products of epicatechin at 24 h exhibited the strongest scavenging capacity for FRAP and ABTS free radicals,which were 287.494±16.941μM and 567.344±13.477μM,respectively.Moreover,compared with the corresponding control group,flavonoid treatment changed the composition of the gut microbiota,mainly by significantly reducing the abundance of harmful bacteria,such as Proteobacteria,and increasing the abundance of beneficial bacteria,such as Flavonifractor.This paper might provide theoretical basis and technical support for the nutritional and pharmacological applications of flavonoids.展开更多
Melatonin(MT)was closely contributed to quality maintenance of postharvest fruits.In this study,sweet cherries were soaked in 100μM MT for 30 min,and the morphological characteristics,textural attributes,contents and...Melatonin(MT)was closely contributed to quality maintenance of postharvest fruits.In this study,sweet cherries were soaked in 100μM MT for 30 min,and the morphological characteristics,textural attributes,contents and composition of phenolics,amino acids and endogenous MT were measured for evaluating the contribution of exogenous MT during storage at 20◦C for 9 d.Results showed that MT treatment delayed decreases of lightness(L*),chromaticity(C*),total soluble solids(TSS)and titratable acidity(TA),and maintained the visual appearance of sweet cherries.And the weight loss and membrane permeability of MT-treated fruits were 17.26%and 9.1%respectively lower than that in CT on day 9,but accompanied with 24.65%higher firmness.Furthermore,LC-MS and q-PCR were used to assess links between phenolic,amino acid and endogenous MT metabolisms,suggesting the improvement of endogenous MT content and transcriptional up-regulation of key genes as influenced by exogenous MT.Similar positive effect on phenolic biosynthesis and accumulation was observed.Besides,the increase of amino acids in MT-treated fruits especially on Phe and Try,precursors of phenolic and MT pathways,further provided evidence on the role of endogenous MT in the quality maintenance of postharvest sweet cherries.展开更多
基金supported by grants from the National Key Research and Development Program of China(2022YFF1100204)the National Natural Science Foundation of China(31972088,32001715)。
文摘Plant polyphenols are potential substitutes for clinicalα-glucosidase inhibitors.Our previous studies indicated that prodelphinidins from Chinese bayberry leaves(BLPs)have strongerα-glucosidase inhibitory activity than other common polyphenols,but they have no safe history of consumption.There is a reasonable prospect that prodelphinidins from Chinese bayberry fruits(BFPs)can improve postprandial hyperglycemia,though known active components are only myricetin and cyanidin-3-O-glucoside.Hence,the aim of this study was to analyze structure and hypoglycemic effect of BFPs of“Biqi”(BQPs)and“Dongkui”(DKPs)cultivars,and compare their difference with BLPs.The contents of BQPs and DKPs were(221.73±0.60)and(136.82±4.33)mg epicatechin(EC)equivalents/g dry weight,respectively.The most subunits were epigallocatechin gallate along with a small amount of epigallocatechin,epicatechin gallate and EC connected by B-type linkages and a small portion of A-type linkages with mean polymerization degree of 4.25 and 4.08,respectively.Importantly,BQPs and DKPs wereα-glucosidase inhibitors with half inhibitory concentration of 11.91 and 9.47μg/m L respectively,which were significantly stronger than BLPs.DKPs could also improve postprandial hyperglycemia of normal mice and high fat diet-induced type II diabetic mice.Therefore,edible prodelphinidins,which have stronger hypoglycemic effect than BLPs,were first found in Chinese bayberry fruits.
基金DST-FIST NO.SR/FST/ETT-378/2014 for sanctioning of the projectVGST,Government of Karnataka.India[VGST/KFIST-4/GRD489]for the sanction of this Project
文摘Latent fingerprints（LFPs） are the major physical evidences for the identification of individuals during crime spot investigation. Till date, numerous methods were followed to visualize LFPs. However, simple,accurate, and cost-effective method has wide scope in advanced forensic field. In our work, Ca2 SiO4：Dy^（3＋）nanopowders（NPs） were fabricated via solution combustion route. The optimized sample was employed for the visualization of overlapped LFPs by the cost effective powder dusting method. The obtained results reveals the complete three levels of ridge characteristics with high sensitivity, reproducibility,selectivity, and reliability on various complex surfaces. The photoluminescence（PL） spectra consist of intense peaks at ～ 480 and 574 nm owing to ~4 F（9/2） →~6 H（15/2） and ~4 F（9/2）→~6 H（13/2） 4 f transitions of Dy3＋ ions,respectively. The photometric properties confirm that the samples exhibit intense white emission with high color purity. Therefore, the prepared NPs could be a definitive choice as an advanced luminescent NPs for forensic, solid state lighting and portable FED devices.
基金sustained by the National Natural Science Foundation of China(No.32001765)the Open Project Program of the State Key Laboratory of Food Nutrition and Safety,China(SKLFNS-KF-202016).
文摘Objectives:The purpose of this study was to evaluate the antibrowning functions of hawthorn leaf extract on fresh-cut potato and its possible mechanism.Materials and Methods:Fresh-cut potatoes were treated with different concentrations(0.01%,0.05%,and 0.1%)of hawthorn leaf extract and preserved at 4 C for 8 days.The appears nee and colour of potato slices were evaluated,along with the content of the phenol,malondialdehyde(MDA),and hydrogen peroxide(H2O2)during cold storage.Meanwhile,the activities of polyphenol oxidase(PPO),peroxidase(POD),phenylalanine ammonia-lyase(PAL),lipoxygenase(LOX),catalase(CAT),superoxide dismutase(SOD),and the antioxidant capacity were determ in ed.Furthermore,the composition of hawthorn leaf extract was analyzed by high-performance liquid chromatographytandem mass spectrometry(HPLC-MS/MS).Results:The addition of hawthorn leaf extract effectively delayed the browning process.It not only enhanced the CAT activity and antioxidant capacity but also reduced the LOX activity and accumulation of MDA and H_(2)O_(2).Meanwhile,the activities of PPO,POD,and PAL as well as the content of phe nol were con trolled.Additionally,25 phe nols,34 flavonoids,and 5 proa nthocya nidins were identified through high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),ideluding caffeic acid,quercetin and catechol.Conelusion:Hawthorn leaf extract significantly alleviated the browning of fresh-cut potato.It could serve as a n atural an tibrowning alter native by stabilizing the membra ne and modulating reactive oxygen species and redox reactions.
基金We thank the National Natural Science Foundation of China(Grant Nos.21901216 and 21871031)the Fund of Science and Technology Agency of Chengdu(2019-YF09-00049-SN)+1 种基金the Open Project Program of Irradiation Preservation Technology Key Laboratory of Sichuan Province,Sichuan Institute of Atomic Energy(No.FZBC2020002)the Sichuan Science and Technology Program(2020YFH0061,2020YJ0222,2021JDRC0018,2021YFS0092,2021YFSY0041,2021YFH0064).
文摘A light-promoted metal-free protocol for the amination of imidazo[1,2-a]pyridines with N-aminopyridinium salt by the assistance of surfactants in water was reported,charactering mild and environmentally benign conditions,as well as great functional group tolerance.Micelles with negatively charged polar surface and hydrophobic core formed from sodium dodecyl sulfate serve as an ideal medium for visible-light mediated radical reaction of cationic pyridine salt and imidazo[1,2-a]pyridine in aqueous phase.The electrostatic interaction between positively charged N-aminopyridinium and negatively charged surface of micelles is of great significance in this method.
基金the National Key Research and Development of China(No.2016YFD0400102)National Natural Science Foundation of China(No.31671918).
文摘Objectives:Optimization of ultrasonic-assisted freezing of Penaeus chinensis by response surface methodology was studied in order to(1)obtain frozen Penaeus chinensis of high quality and(2)provide practical guidance for the application of ultrasonic-assisted freezing in Penaeus chinensis.Materials and Methods:Three independent and major variables were selected,including initial ultrasonic temperature(℃),ultrasonic power(W)and ultrasonic time(s on/2 s off).On the basis of one-factor experiments,17 groups of experiments were established by response surface methodology according to Box-Behnken design.Using multiple regression analysis the experimental data were fitted into a second-order polynomial equation,which was tested by proper statistical methods.Results:The optimal ultrasonic conditions were as follows:initial ultrasonic temperature 0℃,ultrasonic power 180 W,ultrasonic time 5 son/2 s off.Under the optimization conditions,the time of passing through maximum ice crystal generation zone was 105.500 s,which was very close to the predictive passage time of 101.541 s.Conclusions:Initial ultrasonic temperature,ultrasonic time and ultrasonic power played an important role in the process of ultrasonic-assisted freezing of Penaeus chinensis.Response surface methodology was used to optimize the three factors in ultrasonic-assisted freezing,which could greatly shorten the time of passing through the maximum ice crystal generation zone and maintain the tissue structure of Penaeus chinensis well.
基金the Natural Science Foundation of Zhejiang province of China(LGN20C200019)the Major Science and Technology Projects of Agricultural of Ningbo(2019C10033)+1 种基金the Experimental Technology Research project of Zhejiang University(SYB202122)the Fundamental Research Funds for the Central Universities(No.226-2022-00045),China.
文摘Probiotic fermented fruit juice could improve intestinal health with better sensory attributes.The effects of fermentation conditions on flavor quality of fermented bayberry juice were compared through microbial viability and sensory evaluation.Fermentation by combined Streptococcus thermophilus(ST)and Lactobaillus acidophilus(L A)resulted in higher microbial viability and sensory evaluation scores.The fermentation con-ditions were optimized by orthogonal experimental design and Technique for Order Preference by Similarity to an Ildeal Solution analysis(ST and LA in a mass ratio of 3:1;0.6%(mass concentration)inoculation;fermentation time,48 h,at 37℃;10%(mass concentration)added sucrose).Fermentation under these conditions decreased the anthocyanin content of the juice,maintained the total phenolic content,and slightly de-creased the antioxidant capacity.Fermentation reduced aroma volatiles from 42 in fresh juice to 33,as determined by gas chromatography-mass spectrometry-olfactometry(GC-MS-O),the aldehyde content decreased and the alcohol content increased.Lactic acid fermented bayberry juice by ST and LA produced a beverage with desirable consumer attributes,combining the health benefits of fresh juice and probiotics.
基金supported by China Ministry of Science and Technology(No.2021YFA1600800)China Postdoctoral Science Foundation funded project(Nos.2021TQ0216 and 2021M702279)+2 种基金Anhui Provincial Natural Science Foundation(No.2108085UD06)the“Transformational Technologies for Clean Energy and Demonstration”,Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA 21000000)the Fundamental Research Funds for the Central Universities(No.WK2060000021).
文摘Acid-stable and highly active catalysts for the electrocatalytic oxygen evolution reaction(OER)are paramount to the advancement of electrochemical technologies for clean energy conversion and utilization.In this work,based on the density functional theory(DFT)calculations,we systematically investigated the MSb_(2)O_(6)(M=Fe,Co,and Ni)and transition metal(TM)doped MSb_(2)O_(6)(TM-MSb_(2)O_(6),TM=Mn,Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,Ir,and Pt)as potential antimonate-based electrocatalysts for the OER.The stability and OER activity of these considered electrocatalysts were systematically studied under acidic conditions.It was found that Rh-NiSb_(2)O_(6),Pt-CoSb_(2)O_(6),Rh-FeSbO4,and Co-NiSb_(2)O_(6)can serve as efficient and stable OER electrocatalysts,and their OER catalytic activities are better than that of the current state-of-the-art OER catalyst(IrO2).Our findings highlight a family of promising antimonate-based OER electrocatalysts for future experimental verification.
基金supported by the Hainan Provincial Natural Science Foundation of China (321CXTD1012)the National Natural Science Foundation of China (NSFC31871868)the Scientific Research Foundation of Hainan Tropical Ocean University (RHDRC202117),China.
文摘Objectives:The bacteriostatic effects of a citral nanoemulsion against Shewanella putrefaciens CN-32(SHP CN-32)were investigated using in vitro culture and gene expression analysis,forbuilding a potential application in spoilage microorganism control and aquatic products quality maintenance.Materials and Methods:SHP CN-32 was treated by prepared citral nanoemulsion when the minimal inhibitory concentration(MIC)was verified.The growth curve,membrane integrity,scanning electron microscope(SEM)observation,biofilm formation and quorum sensing(QS)signaling molecule Al-2 content were evaluated in different MIC treatment groups(0 to 1.00 MIC).The gene expression status of SHP CN-32 in O and 0.50 MIC groups were compared using transcriptome sequencing and quantitative polymerase chain reaction(PCR).Results:The in vitro culture revealed that the citral nanoemulsion could inhibit the growth of SHP CN-32 with MIC of approximately 200μg/mL.Images of membrane integrity.SEM and biofilm formation suggested significant biological structure damage in bacteria after treatment.Meanwhile,the Qs signaling molecule Al-2 content showed a decline with increasing treatment concentration.Transcriptome sequencing and quantitative PCR revealed that the majority genes related diversified functional metabolic pathways of SHP CN-32 were downregulated at varying degree.Conclusion:A significant bacteriostasis of citral nanoemulsion against SHP CN-32 was verified via the results of growth inhibition,structural destruction,signal molecular decrease and gene expression downregulation of strains.These synergies significantly affect the characteristic expression of SHP CN-32,revealing the application potential as bacteriostat,QS inhibitor and preservative in aquatic products.
基金JSPS KAKENHI[Project no.JP19KK0169 and JP21H04748]for providing financial support for this researchThe Japanese Government(MEXT)Scholarship[Program no.17033]。
文摘Fruit stored in poor conditions undergo biochemical degradations that impact fruit physical qualities,such color and firmness,and reduce beneficial nutritional content including vitamins,flavonoids,phenols,and antioxidants.This study investigated the impact of a postharvest treatment of mandarins with edible coatings to prevent biochemical degradations and minimize color changes.The edible coating evaluated in this study is a composite of pregelatinized corn starch(PS),with a cellulose nano fiber(CF)Pickering emulsifier,and is enriched with basil essential oil(EO).The results of varying each parameter were then analyzed by the Technique for Order of Preference by Similarity to Ideal Solution(TOPSIS)method to identify the best-performing edible coating.Using this method,the leading edible coating was identified as PS5EO3 formulized from 5%pregelatinized corn starch,3%basil essential oil and 0.5%cellulose nanofiber,with a ranking of 0.721 based on quality content,and 0.676 based on percentage change in nutrients after the 12 days of storage at 25℃.Mandarins coated with PS5EO3 significantly suppressed quality losses,and achieving the lowest losses of citric acid(10.45%),while maintaining color stability in terms of color density(14.97%)and percent polymer color(78.14%).
基金financially supported by Ningxia Key Research and Development Programme(2022BBF02007)the Major Science and Technology Special Project of Xinjiang(2022A02009-2).
文摘The degradation of flavonoids helps to elucidate the mechanism of their biological activity,thus guiding individuals to better ingestion and utilization of these compounds.In this study,seven kinds of flavonoids with typical structures were in vitro fermented by fresh feces,and the degradation process of flavonoids were monitored by HPLC,and the gut microbiota constitutes were analyzed by 16 S rRNA microbiota sequencing.Results indicated that all seven kinds of flavonoids could be degraded by intestinal microbiota.In addition,the degradation products of flavonoids showed excellent antioxidant and anti-inflammatory activity,especially the degradation products of epicatechin at 24 h exhibited the strongest scavenging capacity for FRAP and ABTS free radicals,which were 287.494±16.941μM and 567.344±13.477μM,respectively.Moreover,compared with the corresponding control group,flavonoid treatment changed the composition of the gut microbiota,mainly by significantly reducing the abundance of harmful bacteria,such as Proteobacteria,and increasing the abundance of beneficial bacteria,such as Flavonifractor.This paper might provide theoretical basis and technical support for the nutritional and pharmacological applications of flavonoids.
基金supported by the Key Research&Development Program of Shandong Province(2021CXGC010809).
文摘Melatonin(MT)was closely contributed to quality maintenance of postharvest fruits.In this study,sweet cherries were soaked in 100μM MT for 30 min,and the morphological characteristics,textural attributes,contents and composition of phenolics,amino acids and endogenous MT were measured for evaluating the contribution of exogenous MT during storage at 20◦C for 9 d.Results showed that MT treatment delayed decreases of lightness(L*),chromaticity(C*),total soluble solids(TSS)and titratable acidity(TA),and maintained the visual appearance of sweet cherries.And the weight loss and membrane permeability of MT-treated fruits were 17.26%and 9.1%respectively lower than that in CT on day 9,but accompanied with 24.65%higher firmness.Furthermore,LC-MS and q-PCR were used to assess links between phenolic,amino acid and endogenous MT metabolisms,suggesting the improvement of endogenous MT content and transcriptional up-regulation of key genes as influenced by exogenous MT.Similar positive effect on phenolic biosynthesis and accumulation was observed.Besides,the increase of amino acids in MT-treated fruits especially on Phe and Try,precursors of phenolic and MT pathways,further provided evidence on the role of endogenous MT in the quality maintenance of postharvest sweet cherries.
