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1.
Arch Microbiol ; 206(2): 59, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191944

RESUMO

Sichuan Baoning vinegar, a typical representative of Sichuan bran vinegar, is a famous traditional fermented food made from cereals in China. At present, there are few studies on microbial characterization of culturable microorganisms in solid-state fermentation of Sichuan bran vinegar. To comprehensively understand the diversity of lactic acid bacteria, acetic acid bacteria and yeasts, which play an important role in the fermentation of Sichuan bran vinegar, traditional culture-dependent methods combined with morphological, biochemical, and molecular identification techniques were employed to screen and identify these isolates. A total of 34 lactic acid bacteria isolates, 39 acetic acid bacteria isolates, and 48 yeast isolates were obtained. Lactic acid bacteria were dominated by Enterococcus durans, Leuconostoc citreum, Lactococcus lactis, and Lactiplantibacillus plantarum, respectively. Latilactobacillus sakei was the first discovery in cereal vinegar. Acetic acid bacteria were mainly Acetobacter pomorum and A. pasteurianus. The dominant yeast isolates were Saccharomyces cerevisiae, in addition to four non-Saccharomyces yeasts. DNA fingerprinting revealed that isolates belonging to the same species exhibited intraspecific diversity, and there were differences between phenotypic and genotypic classification results. This study further enriches studies on cereal vinegar and lays a foundation for the development of vinegar starters.


Assuntos
Ácido Acético , Lactobacillales , Lactobacillales/genética , Saccharomyces cerevisiae , Bactérias/genética , China , Grão Comestível
2.
J Environ Manage ; 351: 119935, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154221

RESUMO

Heavy metal and antibiotic-resistant bacteria from livestock feces are ecological and public health problems. However, the distribution and relationships of antibiotic resistance genes (ARGs), heavy metal resistance genes (HMRGs), and virulence factors (VFs) and their transmission mechanisms remain unclear. Therefore, we investigated the resistance of Escherichia coli, the prevalence of its ARGs, HMRGs, and VFs, and their transmission mechanisms in livestock fresh feces (FF), composted feces (CF), and fertilized soil (FS). In total, 99.54% (n = 221) and 91.44% (n = 203) of E. coli were resistant to at least one antibiotic and one heavy metal, respectively. Additionally, 72.52% (n = 161) were multi-drug resistant (MDR), of which Cu-resistant E. coli accounted for 72.67% (117/161). More than 99.34% (88/89) of E. coli carried multidrug ARGs, VFs, and the Cu resistance genes cueO and cusABCRFS. The Cu resistance genes cueO and cusABCRFS were mainly located on chromosomes, and cueO and cusF were positively associated with HMRGs, ARGs, and VFs. The Cu resistance genes pcoABCDRS were located on the plasmid pLKYL-P02 flanked by ARGs in PF18C from FF group and on chromosomes flanked by HMRGs in SAXZ1-1 from FS group. These results improved our understanding of bacterial multidrug and heavy metal resistance in the environment.


Assuntos
Antibacterianos , Metais Pesados , Animais , Antibacterianos/farmacologia , Escherichia coli/genética , Esterco/microbiologia , Gado , Solo , Genes Bacterianos , Metais Pesados/farmacologia , Bactérias/genética
3.
Microb Ecol ; 85(1): 232-246, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35064809

RESUMO

The decline in soil nutrients is becoming a major concern of soil degradation. The possibility of using organic waste as a soil additive to increase nutrients and essential components is significant in soil quality protection and waste management. The aim of this study was to investigate the effects of composted spent mushroom substrate (MS), giant panda feces (PF), and cattle manure (CM) as organic fertilizers in soil microbial communities and metabolites in blueberry orchard in China, which were measured by using high-throughput sequencing and gas chromatography-mass spectrometry (GC-MS)-based metabolomics. Altogether, 45.66% of the bacterial operational taxonomic units (OTUs) and 9.08% of the fungal OTUs were detected in all treatments. Principal coordinates analysis demonstrated that the bacterial and fungal communities in MS and PF treatments were similar, whereas the communities in the not-organic fertilized control (CK) were significantly different from those in the organic fertilizer treatments. Proteobacteria, Acidobacteria, and Bacteroidetes were the dominant bacterial phyla, and Basidiomycota, Ascomycota, and Mortierellomycota the dominant fungal phyla. Redundancy analysis indicated that pH and available potassium were the main factors determining the composition of microbial communities. The fungal genera Postia, Cephalotrichum, and Thermomyces increased in organic fertilizer treatments, and likely promoted the degradation of organic fertilizers into low molecular-weight metabolites (e.g., amino acids). PCA and PLS-DA models showed that the metabolites in CK were different from those in the other three treatments, and those in CM were clearly different from those in MS and PF. Co-occurrence network analysis showed that several taxa correlated positively with amino acid contents. The results of this study provide new insights into organic waste reutilization and new directions for further studies.


Assuntos
Ascomicetos , Mirtilos Azuis (Planta) , Microbiota , Animais , Bovinos , Solo/química , Fertilizantes/análise , Mirtilos Azuis (Planta)/metabolismo , Nitrogênio/metabolismo , Bactérias , Ascomicetos/metabolismo , Microbiologia do Solo
4.
Appl Microbiol Biotechnol ; 107(22): 6985-6998, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37702791

RESUMO

The presence of cypermethrin in the environment and food poses a significant threat to human health. Lactic acid bacteria have shown promise as effective absorbents for xenobiotics and well behaved in wide range of applications. This study aimed to characterize the biosorption behavior of cypermethrin by Lactiplantibacillus plantarum RS60, focusing on cellular components, functional groups, kinetics, and isotherms. Results indicated that RS60 exopolysaccharides played a crucial role removing cypermethrin, with the cell wall and protoplast contributing 71.50% and 30.29% to the overall removal, respectively. Notably, peptidoglycans exhibited a high affinity for cypermethrin binding. The presence of various cellular surface groups including -OH, -NH, -CH3, -CH2, -CH, -P = O, and -CO was responsible for the efficient removal of pollutants. Additionally, the biosorption process demonstrated a good fit with pseudo-second-order and Langmuir-Freundlich isotherm. The biosorption of cypermethrin by L. plantarum RS60 involved complex chemical and physical interactions, as well as intraparticle diffusion and film diffusion. RS60 also effectively reduced cypermethrin residues in a fecal fermentation model, highlighting its potential in mitigating cypermethrin exposure in humans and animals. These findings provided valuable insights into the mechanisms underlying cypermethrin biosorption by lactic acid bacteria and supported the advancement of their application in environmental and health-related contexts. KEY POINTS: • Cypermethrin adsorption by L. plantarum was clarified. • Cell wall and protoplast showed cypermethrin binding ability. • L. plantarum can reduce cypermethrin in a fecal fermentation model.

5.
J Environ Manage ; 325(Pt B): 116626, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36327606

RESUMO

As a major intermediate metabolite of synthetic pyrethroids, the occurrence of 3-phenoxybenzoic acid hinders the decomposition of the parent pesticide and poses uncertain risks to environmental ecology and living organisms. Strain Aspergillus oryzae M-4 was previously reported to degrade 3-PBA and several substances were identified as downstream transformation products (TPs). But the mechanism underlying the cleavage of ether bond remains largely unclear. Here, we attempted to address such concern through identifying the peripheral TPs and analyzing transcriptomics, coupled with serial batch degradation experiments. Analysis results of chromatographic/mass spectrometry suggested that 3-PBA underwent twice hydroxylation, to yield mono- and dihydroxylated 3-PBA successively. In parallel, a mutual transformation between 3-PBA and 3-phenoxybenzyl alcohol (3-PBOH) also existed. The proposal of peripheral pathway represents an important advance towards fully understanding the whole 3-PBA metabolism in M-4. A specific altered metabolization was found for the first time, that is, resting cells of M-4 skipped the reduction step and initiate hydroxylation directly, by comparison with growing cells. Transcriptome analysis indicated that 3-PBA induced the up-regulation of genes related to energy investment, oxidative stress response, membrane transport and DNA repair. In-depth functional interpretation of differential expression genes suggested that the generation 3-PBOH and hydroxylated 3-PBA may be due to the participation of flavin-dependent monooxygenases (FMOs) and cytochrome P450 (CYP450), respectively. This study provides new insight to reveal the biodegradation mechanism of 3-PBA by A. oryzae M-4.


Assuntos
Aspergillus oryzae , Piretrinas , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Transcriptoma , Perfilação da Expressão Gênica
6.
J Appl Microbiol ; 132(4): 2968-2979, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35025132

RESUMO

AIMS: The current study aimed to evaluate the capacity of two Lactiplantibacillus plantarum strains to remove Bisphenol A (BPA) and to determine the preliminary removal mechanisms underlying this process. METHODS AND RESULTS: The BPA removal capacity of L. plantarum RS20D and DL7X was assessed by HPLC analysis. The effect of various treatments (physical, chemical and enzymatic) on two strains were studied to understand which interaction types worked. The different cellular components of them were also subjected to binding assays. Additionally, Fourier-transform infrared spectroscopy (FTIR) was performed to identify the functional groups related to the BPA-binding process. Results show that various treatments enhanced the binding capacity of two strains, the effect of sodium dodecyl sulphate was the most outstanding (p < 0.05). Hydrogen bonding and hydrophobic interactions likely occurred. Peptidoglycans showed the highest binding capability, protoplasts and teichoic acids might also exert a binding effect. -OH, C=O, -CH, -NH, C-N, C-O and P=O participated in BPA binding by the two L. plantarum lines. CONCLUSIONS: Peptidoglycans, protoplasts and teichoic acid played a vital role in the binding of BPA. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provided a theoretical foundation for developing effective dietary strategies with foodborne L. plantarum to remove food contaminants.


Assuntos
Compostos Benzidrílicos , Fenóis , Compostos Benzidrílicos/química , Interações Hidrofóbicas e Hidrofílicas , Fenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Appl Microbiol ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36626738

RESUMO

AIMS: Beads containing heat-inactivated bacterial biomaterial (BBBs) were prepared for removal of cypermethrin (CPM) and the conditions for this removal were evaluated and optimized via orthogonal experiments. The adsorption characteristics of BBBs and the binding mechanism were then explored. METHODS AND RESULTS: Single-factor and orthogonal experiments were carried out to optimize five factors affecting the production and effectivity of the beads. The adsorption rate of CPM could reach 98% with beads prepared under optimized conditions: equal volumes of Lactobacillus cell debris derived from 1 × 1011 CFU; 2% hydroxypropyl-ß-cyclodextrin and 2.5% activated carbon concentration, were mixed to give mixture TM, and this and SA, was mixed 1:4 with sodium alginate (SA) and beads were prepared using a 26-Gauge needle). The best adsorption conditions were initial CPM concentration of 10 mg l-1, incubation time of 24 h, and rotational speed of 180 rpm. BBBs have a well-formed structure and abundant surface functional groups, such as -COOH, -OH, -NH, -CH, -CO, -C = C. The adsorption process conformed to pseudo-second-order kinetic, and it was also a Freundlich monolayer adsorption, and the calculated maximum adsorption capacity was 9.69 mg g-1 under optimized conditions. CONCLUSIONS: BBBs showed the highest CPM removal capacity and a good tolerance ability.

8.
J Appl Microbiol ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36626792

RESUMO

AIMS: Beads containing heat-inactivated bacterial biomaterial (BBBs) were prepared for removal of cypermethrin (CPM) and the conditions for this removal were evaluated and optimized via single-factor coupled orthogonal experiments based on five factors. The adsorption characteristics of BBBs and the binding mechanism were then explored. METHODS AND RESULTS: Results showed that the adsorption rate of CPM could reach 98% with beads prepared under optimized conditions: equal volumes of Lactobacillus cell debris derived from 1×1011 CFU; 2% hydroxypropyl-ß-cyclodextrin and 2.5% activated carbon concentration, were mixed to give mixture TM, and this and SA, was mixed 1:4 with sodium alginate (SA) and beads were prepared using a 26-Gauge needle). The best adsorption conditions were initial CPM concentration of 10 mg l-1, incubation time of 24 h, and rotational speed of 180 rpm. BBBs have a well-formed structure and abundant surface functional groups, such as -COOH, -OH, -NH, -CH, -CO, -C=C. The adsorption process conformed to pseudo-second-order kinetic, and it was also a Freundlich monolayer adsorption, and the calculated maximum adsorption capacity was 9.69 mg g-1 under optimized conditions. CONCLUSIONS: BBBs showed the highest CPM removal capacity and a good tolerance ability. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provided a theoretical foundation for developing an adsorbent with heat-inactivated Lactobacillus plantarum (L. plantarum) RS60 for removing CPM in wastewater or drinks.

9.
Anesth Analg ; 134(6): 1203-1214, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35147575

RESUMO

Numerous animal models have been used to study developmental neurotoxicity associated with short-term or prolonged exposure of common general anesthetics at clinically relevant concentrations. Pediatric anesthesia models using the nonhuman primate (NHP) may more accurately reflect the human condition because of their phylogenetic similarity to humans with regard to reproduction, development, neuroanatomy, and cognition. Although they are not as widely used as other animal models, the contribution of NHP models in the study of anesthetic-induced developmental neurotoxicity has been essential. In this review, we discuss how neonatal NHP animals have been used for modeling pediatric anesthetic exposure; how NHPs have addressed key data gaps and application of the NHP model for the studies of general anesthetic-induced developmental neurotoxicity. The appropriate application and evaluation of the NHP model in the study of general anesthetic-induced developmental neurotoxicity have played a key role in enhancing the understanding and awareness of the potential neurotoxicity associated with pediatric general anesthetics.


Assuntos
Anestesia , Anestésicos Gerais , Anestésicos , Síndromes Neurotóxicas , Anestesia/efeitos adversos , Anestésicos/toxicidade , Anestésicos Gerais/toxicidade , Animais , Animais Recém-Nascidos , Criança , Humanos , Síndromes Neurotóxicas/etiologia , Filogenia , Primatas
10.
Int J Mol Sci ; 23(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35628620

RESUMO

3-PBA is a major degradation intermediate of pyrethroids. Its widespread existence in the environment poses a severe threat to the ecosystem and human health. This study evaluated the adsorption capacity of L. plantarum RS20 toward 3-PBA. Batch adsorption experiments indicated that the optimal adsorption conditions were a temperature of 37 °C and initial pH of 6.0-8.0, under which the removal rate was positively correlated with the cell concentration. In addition, there was no link between the incubation time and adsorption rate. The kinetic study showed that the adsorption process fitted well with the pseudo-second-order model, and the adsorption isotherms could be described by both Langmuir and Freundlich equations. Heat and acid treatments showed that the ability of strain RS20 in removing 3-PBA was independent of microbial vitality. Indeed, it was involved with chemisorption and physisorption via the cell walls. The cell walls made the highest contribution to 3-PBA removal, according to the adsorption experiments using different cellular components. This finding was further reconfirmed by SEM. FTIR spectroscopy analysis indicated that carboxyl, hydroxyl, amino groups, and -C-N were the functional sites for the binding of 3-PBA. The co-culture experiments showed that the adsorption of strain RS20 enhanced the degradation of 3-PBA by strain SC-1. Strain RS20 could also survive and effectively remove 3-PBA in simulated digestive juices. Collectively, strain RS20 could be employed as a biological detoxification agent for humans and animals by eliminating 3-PBA from foods, feeds, and the digestive tract in the future.


Assuntos
Lactobacillus plantarum , Poluentes Químicos da Água , Adsorção , Benzoatos , Ecossistema , Poluentes Químicos da Água/química
11.
BMC Plant Biol ; 20(1): 267, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517649

RESUMO

BACKGROUND: Soil and water pollution due to nitrate are becoming increasingly serious worldwide. The government also put forward relevant governance policies, and a large number of scholars studied chemical physics and other methods to remove nitrate in water, but the cost was substantial. Studies have found that planting systems including grasses have the potential to remove nitrates. However, there are few studies on nitrate linked pathway and nitrate assimilation during its early growth. RESULTS: We have evaluated three different feed-plant species with three levels of overnight seed nitrate treatments along with a control. The activity of different enzymes from 2 weeks old shoots was measured to get a comprehension of proline-associated pentose phosphate pathway coupled with nitrate assimilation and phenolic-linked antioxidant response system in these species under nitrate treatments. All three feed-plant species showed high nitrate tolerance during germination and early growth stages. It is perceived that the accumulation of total soluble phenolics and total antioxidant activity was high in all three feed-plant species under high nitrate treatments. In terms of high G6PDH activity along with low SDH activity in alfalfa, there may be a shift of carbon flux in this species under high nitrate treatments. Higher activity of these enzymes along with higher SOD and GPX activity was observed in alfalfa. The efficient mechanism of nitrate stress tolerance of alfalfa also correlated with higher photochemical efficiency. Perennial ryegrass also showed excellent potential under high nitrate treatments by adopting an efficient mechanism to counter nitrate-induced oxidative stress. CONCLUSIONS: Under the condition of nitrate treatment, the germination rates of the three feed-plant species are still ideal, and they have good enzyme activity and have the potential to remove nitrate.


Assuntos
Antioxidantes/farmacologia , Festuca/metabolismo , Lolium/metabolismo , Medicago sativa/metabolismo , Nitratos/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Sementes/metabolismo , Catalase/metabolismo , Relação Dose-Resposta a Droga , Festuca/efeitos dos fármacos , Germinação/efeitos dos fármacos , Glucosefosfato Desidrogenase/metabolismo , Lolium/efeitos dos fármacos , Medicago sativa/efeitos dos fármacos , Nitrato Redutase/metabolismo , Nitratos/farmacologia , Peroxidase/metabolismo , Fenóis/farmacologia , Fotossíntese/efeitos dos fármacos , Prolina/metabolismo , Prolina Oxidase/metabolismo , Sementes/efeitos dos fármacos , Succinato Desidrogenase/metabolismo , Superóxido Dismutase/metabolismo
12.
Anal Bioanal Chem ; 412(5): 1049-1062, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31853602

RESUMO

Magnetic molecular imprinted polymers with ionic liquid used as an auxiliary solvent (IL@MMIPs) for the recognition of the methyl carbamate pesticide carbaryl (CBR) in foodstuff have been synthesized. The properties and application of IL@MMIPs were determined. The kinetic and isotherm adsorption processes were found to follow the pseudo-second-order and the Scatchard models, respectively. The selective experiment showed that the IL@MMIPs exhibited good selectivity to CBR compared to magnetic nonimprinted polymers with IL (IL@MNIPs). By using the IL@MMIPs as an adsorbent for the enrichment of CBR in food samples, the limit of detection (LOD, S/N = 3) and the limit of quantitation (LOQ, S/N = 10) of this method were 3 µg kg-1 and 10 µg kg-1, respectively. Compared with the traditional method, the IL@MMIP method has better recoveries (83.23-99.83%), precision (1.12-2.09%), and stabilization (intraday, 1.08-2.81%; interday, 2.26-3.30%). IL@MMIPs are an ideal adsorbent that could be applied to conveniently detect CBR in complex food, and the proposed method can be considered as a selective and sensitive alternative to traditional methods with affordable cost, avoiding the complex pretreatment procedure. Graphical abstract .


Assuntos
Carbaril/isolamento & purificação , Contaminação de Alimentos/análise , Inseticidas/análise , Líquidos Iônicos/química , Nanopartículas de Magnetita/química , Impressão Molecular , Polímeros/química , Adsorção , Cristalografia por Raios X , Cinética , Limite de Detecção , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
13.
Curr Microbiol ; 77(12): 3821-3830, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32979055

RESUMO

Aflatoxins are toxic secondary metabolic products, which exert great hazards to human and animal health. Decontaminating aflatoxins from food ingredients to a threshold level is a prime concern for avoiding risks to the consumers. Biological decontamination processes of aflatoxins have received widespread attention due to their mild and environmental-friendly nature. Many reports have been published on the decontamination of aflatoxins by microorganisms, especially lactic acid bacteria (LAB), a well-explored probiotic and generally recognized as safe. The present review aims at updating the decontamination of produced aflatoxins using LAB, with an emphasis on the decontamination mechanism and influence factors for decontamination. This comprehensive analysis provides insights into the binding mechanisms between LAB and aflatoxins, facilitating the theoretical and practical application of LAB for decontaminating hazardous substances in food and agriculture.


Assuntos
Aflatoxinas , Lactobacillales , Aflatoxinas/análise , Animais , Descontaminação , Contaminação de Alimentos/análise , Humanos
14.
Biodegradation ; 31(1-2): 139-152, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32306137

RESUMO

Pesticides introduced inadvertently or deliberately into environment by anthropogenic activity have caused growing global public concern, therefore the search of approaches for elimination of such xenobiotics should be encouraged. A cypermethrin-degrading bacterial strain Bacillus licheniformis B-1 was found to efficiently degrade carbaryl in LB medium at concentrations of 50-300 mg L-1 within 48 h, during which temperature and pH played important roles as reflected by increase in pollutant depletion. A stimulatory effect of Fe3+ and Mn2+ on microbial growth was observed, whereas Cu2+ caused inhibition of degradation. Results showed that 1-naphthol was a major transformation product of carbaryl which was further metabolised. An approximately 29 kDa carbaryl-degrading enzyme was purified from B-1 with 15.93-fold purification and an overall yield of 6.02% was achieved using ammonium sulphate precipitation, DEAE-Sepharose CL-6B anion-exchange chromatography and Sephadex G-100 gel filtration. The enzyme was identified through nano reversed-phase liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry as a phosphodiesterase (PDE). This is the first report on the characterization of carbaryl-degrading by Bacillus spp. and the role of a PDE in carbaryl-detoxifying. Also, strain B-1 showed versatile in carbosulfan, isoprocarb and chlorpyrifos degradation, demonstrating as ideal candidate for environment bioremediation.


Assuntos
Bacillus licheniformis , Clorpirifos , Biodegradação Ambiental , Carbaril , Hidrolases
15.
Mikrochim Acta ; 187(1): 40, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31828439

RESUMO

The authors have synthesized a phosphorescent probe of type SiO2-QD-MIP, where QD stands for Mn:ZnS quantum dots and MIP is a polymer coating that was molecularly imprinted with cephalexin. The nanoprobe with high specificity was prepared via sol-gel polymerization using thioglycolic acid (TGA)-modified QDs as luminescent materials, cephalexin as the template, 3-aminopropyltriethoxysilane as the functional monomer, and tetraethoxysilane as the crosslinking agent. The SiO2-QD-MIPs were characterized by X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectrometry. The orange emission of the probe, with excitation/emission maxima at 295/590 nm, decreases linearly in the 2.5-50 µg·L-1 cephalexin concentration range with a limit of detection (LOD) of 0.81 µg·L-1. The nanoprobe was successfully applied to the determination of cephalexin in (spiked) raw milk and milk powder. The recoveries ranged from 91.7 to 103.7%.


Assuntos
Cefalexina/análise , Substâncias Luminescentes/química , Impressão Molecular , Polímeros/química , Pontos Quânticos/química , Tioglicolatos/química , Substâncias Luminescentes/síntese química , Manganês/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Sulfetos/química , Propriedades de Superfície , Compostos de Zinco/química
16.
Anal Biochem ; 556: 145-151, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29990465

RESUMO

We have developed a label-free, enzyme-free, modification-free and DNA extraction-free fluorescent aptasensing (LEFA) method for detection of E. coli O157:H7 based on G-quadruplex formation using two ingeniously designed hairpin probes (GHP1 and GHP2). In the presence of E. coli O157:H7, it released the single stranded initiation sequence (IS) resulting in the toehold strand displacement between GHP1 and GHP2, which in turn led to the cyclic reuse of the production of DNA assemblies with numerous G-quadruplex structures and initiation sequences. Then these G-quadruplex structures can be recognized quickly by N-methyl mesoporphyrin IX (NMM) resulting in significantly enhanced fluorescence. The LEFA method was successfully implemented for detecting E. coli O157:H7 with a detection limit of 66 CFU/mL in pure culture, 10 CFU/mL and 1 CFU/mL after pre-incubation of the milk and tap water for 4 and 8 h, respectively. Moreover, the strategy could distinguish viable E. coli O157:H7 from dead E. coli O157:H7 and other species of pathogen cells. Furthermore, the whole process of the strategy is accomplished within 100 min. The results indicated that the approach may be used to effectively control potential microbial hazards in human health, food safety, and animal husbandry.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Escherichia coli O157 , Quadruplex G , Mesoporfirinas/química , Animais , Humanos , Limite de Detecção
17.
Biochem Biophys Res Commun ; 477(4): 521-526, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27262438

RESUMO

Lung adenocarcinoma, as a common form of non-small cell lung cancer, poses a significant threat to public health worldwide. Previous studies have reported that flotillin-2 (Flot2) is often overexpressed in various tumors and is h correlated with tumor progression and patient survival. Dysregulated microRNA (miRNA) is associated with various cancers, including lung adenocarcinoma. However, little is known about the miRNAs targeting Flot2 in lung adenocarcinoma. In this study, we found that the expression level of miR-485 was downregulated in four lung adenocarcinoma cell lines and tissues and that the reduced miR-485 expression was associated with tumor metastasis. Luciferase assay revealed that Flot2 is direct target of miR-485, while the expression levels of Flot2 were inversely correlated with the expression levels of miR-485 in lung adenocarcinoma tissues. Ectopic Flot2 could significantly reverse miR-485-mediated inhibition of metastasis and EMT, demonstrating Flot2 downregulation is involved in function of miR-485. Subsequently, we found that miR-485 suppressed the activity of PI3K/AKT/mTOR signaling in lung adenocarcinoma cells. In conclusion, the present study provided novel insight into the molecular mechanism of lung adenocarcinoma progression and demonstrating miR-485 as a potential therapeutic target in human lung adenocarcinoma.


Assuntos
Adenocarcinoma/patologia , Transição Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/patologia , Proteínas de Membrana/genética , MicroRNAs/genética , Metástase Neoplásica/prevenção & controle , Adenocarcinoma/genética , Humanos , Neoplasias Pulmonares/genética , Regulação para Cima
18.
Anesthesiology ; 125(1): 133-46, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27183169

RESUMO

BACKGROUND: Animals exposed to sevoflurane during development sustain neuronal cell death in their developing brains. In vivo micro-positron emission tomography (PET)/computed tomography imaging has been utilized as a minimally invasive method to detect anesthetic-induced neuronal adverse effects in animal studies. METHODS: Neonatal rhesus monkeys (postnatal day 5 or 6, 3 to 6 per group) were exposed for 8 h to 2.5% sevoflurane with or without acetyl-L-carnitine (ALC). Control monkeys were exposed to room air with or without ALC. Physiologic status was monitored throughout exposures. Depth of anesthesia was monitored using quantitative electroencephalography. After the exposure, microPET/computed tomography scans using F-labeled fluoroethoxybenzyl-N-(4-phenoxypyridin-3-yl) acetamide (FEPPA) were performed repeatedly on day 1, 1 and 3 weeks, and 2 and 6 months after exposure. RESULTS: Critical physiologic metrics in neonatal monkeys remained within the normal range during anesthetic exposures. The uptake of [F]-FEPPA in the frontal and temporal lobes was increased significantly 1 day or 1 week after exposure, respectively. Analyses of microPET images recorded 1 day after exposure showed that sevoflurane exposure increased [F]-FEPPA uptake in the frontal lobe from 0.927 ± 0.04 to 1.146 ± 0.04, and in the temporal lobe from 0.859 ± 0.05 to 1.046 ± 0.04 (mean ± SE, P < 0.05). Coadministration of ALC effectively blocked the increase in FEPPA uptake. Sevoflurane-induced adverse effects were confirmed by histopathologic evidence as well. CONCLUSIONS: Sevoflurane-induced general anesthesia during development increases glial activation, which may serve as a surrogate for neurotoxicity in the nonhuman primate brain. ALC is a potential protective agent against some of the adverse effects associated with such exposures.


Assuntos
Anestésicos Inalatórios/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico por imagem , Éteres Metílicos/efeitos adversos , Tomografia por Emissão de Pósitrons/métodos , Anestesia Geral , Anilidas , Animais , Animais Recém-Nascidos , Eletroencefalografia/efeitos dos fármacos , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/metabolismo , Processamento de Imagem Assistida por Computador , Macaca mulatta , Masculino , Piridinas , Compostos Radiofarmacêuticos , Sevoflurano , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/metabolismo , Tomografia Computadorizada por Raios X
19.
Appl Microbiol Biotechnol ; 100(22): 9773-9786, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27678114

RESUMO

A novel filamentous fungus M-4 strain was isolated from soy sauce koji and identified as Aspergillus oryzae (Collection number: CGMCC 11645) on the basis of morphological characteristics and internal transcribed spacer sequence. M-4 could degrade 80.62 % of 3-phenoxybenzoic acid (3-PBA; 100 mg L-1) within 5 days. 3-PBA degradation occurred in accordance with first-order kinetics. The degradation metabolites of 3-PBA were identified through high-performance liquid chromatography-mass spectrometry (HPLC-MS). Relevant enzymatic activities and substrate utilization were also investigated, which indicated that M-4 could effectively degrade the intermediates of 3-PBA. Base on analysis of these metabolites, a novel biochemical pathway for the degradation of 3-PBA was proposed. There exists a mutual transformation between 3-phenoxy-benzyl alcohol and 3-PBA, which was firstly reported about the degradation of 3-PBA and may be attributed to self-protection transformation of M-4; subsequently, 3-PBA was gradually transformed into phenol, 3-hydroxy-5-phenoxy benzoic acid, protocatechuic acid and gallic acid. The safety of M-4 was evaluated via an acute toxicity test in vivo. The biodegradation ability of M-4 without toxic effects reveals that this fungus may be likely to be used for eliminating 3-PBA from contaminated environment or fermented foods.


Assuntos
Aspergillus oryzae/metabolismo , Benzoatos/metabolismo , Fungos/metabolismo , Aspergillus oryzae/classificação , Aspergillus oryzae/genética , Aspergillus oryzae/isolamento & purificação , Biotransformação , Cromatografia Líquida , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Espectrometria de Massas , Redes e Vias Metabólicas , Filogenia , Análise de Sequência de DNA , Alimentos de Soja/microbiologia
20.
Appl Microbiol Biotechnol ; 99(19): 8187-98, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26022858

RESUMO

Aspergillus niger YAT strain was obtained from Chinese brick tea (Collection number: CGMCC 10,568) and identified on the basis of morphological characteristics and internal transcribed spacer (ITS) sequence. The strain could degrade 54.83 % of ß-cypermethrin (ß-CY; 50 mg L(-1)) in 7 days and 100 % of 3-phenoxybenzoic acid (3-PBA; 100 mg L(-1)) in 22 h. The half-lives of ß-CY and 3-PBA range from 3.573 to 11.748 days and from 5.635 to 12.160 h, respectively. The degradation of ß-CY and 3-PBA was further described using first-order kinetic models. The pathway and mechanism of ß-CY degraded by YAT were investigated by analyzing the degraded metabolites through high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). Relevant enzymatic activities and substrate utilization were also investigated. ß-CY degradation products were analyzed. Results indicated that YAT strain transformed ß-CY into 3-PBA. 3-PBA was then gradually transformed into permethric acid, protocatechuic acid, 3-hydroxy-5-phenoxy benzoic acid, gallic acid, and phenol gradually. The YAT strain can also effectively degrade these metabolites. The results indicated that YAT strain has potential applications in bioremediation of pyrethroid insecticide (PI)-contaminated environments and fermented food.


Assuntos
Aspergillus niger/metabolismo , Piretrinas/metabolismo , Aspergillus niger/classificação , Aspergillus niger/genética , Aspergillus niger/isolamento & purificação , Biodegradação Ambiental , China , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Cinética , Dados de Sequência Molecular , Filogenia , Piretrinas/química , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Alimentos de Soja/microbiologia , Chá/microbiologia , Vinho/microbiologia
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