Enterobacterales and other non-fermenting Gram-negative bacteria have become a threat worldwide owing to the frequency of multidrug resistance in these pathogens. On the other hand, efficacious therapeutic options are quickly diminishing. The aims of this study were to describe the susceptibility of 50 multiresistant Gram-negative bacteria, mostly pan-resistant, against old and less-used antimicrobial drugs and to investigate the presence of antimicrobial resistance genes.
A total of 50 genetically distinct isolates were included in this study, including 14 Acinetobacter baumannii (belonging to ST79, ST317, ST835 and ST836), 1 Pseudomonas aeruginosa (ST245), 8 Serratia marcescens and 27 Klebsiella pneumoniae (belonging to ST11, ST340, ST258, ST16, ST23, ST25, ST101, ST234, ST437 and ST442). The isolates were submitted to antimicrobial susceptibility testing and whole-genome sequencing to evaluate lineages and resistance genes.
Our results showed that some strains harboured carbapenemase genes, e.g. bla
mannii, ceftazidime/avibactam against Enterobacterales, and fosfomycin against S. marcescens.The potent aroma compounds in butter from four kinds of Chinese butter hotpot seasoning were first investigated by analyzing the isolates from solid-phase microextraction. A total of 49 aroma compounds were identified, and 23 of them were highly correlated with the aroma profiles of the butter by partial least squares regression analysis. Aroma extract dilution analysis and odor activity value calculations were applied to further reveal the dominant odorants. Fifty-three odorants with flavor dilution factors between 1 and 1024 were identified and OAVs of 17 odorants were greater than 1. Finally, an aroma recombination experiment was prepared by mixing the aroma-active compounds (OAVs > 1), and the aroma profile of the recombination showed good agreement with that of the original sample. Omission tests showed that 2-furfurylthiol, 2-acetylthiazole, anethole, (E)-2-decenal, and 1,8-cineole were the key odorants for the overall aroma of butter.The fatty acid content of flour is an important indicator for determining the deterioration of flour. We propose a novel rapid measurement method for fatty acid content during flour storage based on a self-designed color-sensitive gas sensor array. First, a color-sensitive gas sensor array was prepared to capture the odor changes during flour storage. The sensor features were then optimized using genetic algorithm (GA), ant colony optimization (ACO) and particle swarm optimization (PSO). Finally, **** propagation neural network (BPNN) models were established to measure the fatty acid content during flour storage. Experimental results showed that the optimization effects of the three algorithms improved in the following order GA less then ACO less then PSO, for the sensor features optimization. https://www.selleckchem.com/products/MK-1775.html In the validation set, the determination coefficient of the best PSO-BPNN model was 0.9837. The overall results demonstrate that the models established on the optimized features can realize rapid measurements of fatty acid content during flour storage.In bottled wines, haze and turbidity are phenomena to be avoided. Since bentonite fining is a common process to clarify wines removing heat unstable proteins, a theoretical study on the adsorption of three Charged Model Molecules (CMMs, egg albumin, polyphenols and riboflavin) was carried out to deep comprehend this chemical phenomenon. Four bentonites were adopted and finely characterized together with the potential release of Na+ and Ca2+ cations, revealing suitable for RT albumin removal within 120 min. Better results in terms of adsorbed quantity were achieved by adopting 12%v/v EtOH/H2O solvent and by swelling bentonites for 24 h before use. With the most performing sample (Na/Ca_0.27), a comprehensive study on simultaneous adsorption of the three CMMs was performed, resulting in polyphenols adsorption increase due to their interactions with albumin. Notwithstanding the majority of albumin and riboflavin was successfully removed, ca. 40-50% of tested polyphenols was preserved.Cadmium, inorganic arsenic and, potentially, dimethyl arsenic acid are carcinogens widely elevated in rice. Here it was identified that the food-safe and common cadmium chelator citric acid efficiently removed cadmium from intact grain via pre-soaking procedure, while also reducing arsenic species. A twostep pre-soaking stage was developed whereby rice was first incubated, at ambient temperature, in 1 M citric acid for 12 h, and then in 1 M calcium carbonate for another 12 h, the latter step to neutralize pH, followed by cooking. When 10 different individual types of rice were processed in such a way this resulted in removal rates of 79% for cadmium, 81% for inorganic arsenic and a 66% for DMA. The technology is particularly suitable for bulk food processing and could be deployed in the most cadmium and arsenic impacted regions where rice is a staple.Cyclodextrin (CD)-metal-organic frameworks (MOFs) are developed as a new type of food-acceptable multi-porous material, which shows a great potential for controlled volatile compound release. This study aimed to synthesize CD-MOFs from potassium nitrate, crystallized with α-cyclodextrin (α-CD), β-CD or γ-CD, and their complex capacities were further evaluated using menthol encapsulation. Compared with CD, all the CD-MOFs had highly ordered crystal structures and more regular shapes. β-CD-MOF showed better thermal stability, with an initial thermal degradation temperature of 253 °C, higher than the other two CD-MOFs. The CD-MOFs were used for menthol encapsulation and the resulting menthol concentration within the inclusion complexes (ICs) was determined. The menthol concentration in ICs followed the order β-CD-MOF > β-CD > γ-CD-MOF > γ-CD > α-CD ≥ α-CD-MOF. The menthol content and encapsulation efficiency of β-CD-MOF were 21.76% (w/w) and 22.54% (w/w) respectively, significantly higher than those of other reported solid materials, such as amylose, CD and V-type starch.Ochratoxin A (OTA) is a toxic metabolite that is widely distributed in food products. Herein, we proposed a new fluorescent aptasensor for OTA detection by using cascade strand displacement reaction. The binding of OTA and OTA aptamer on magnetic beads surface inhibited its hybridization with complementary DNA, and subsequently initiated the strand displacement reaction that induced amplified fluorescence signal. By tracing fluorescence response, our method demonstrated an improved detection limit of 0.63 ng/mL, a short assay time of 110 min, and a satisfactory detection specificity by using ochratoxin B, aflatoxin B1, and zearalenone as control toxins. Recovery studies were conducted by spiking OTA in real food samples, including white wine, red wine, cereal drink, coffee beverage and tea beverage, and confirmed desirable accuracy and practical applicability of our method. Therefore, our method may have a great potential use in the food quality control in the future.
Enterobacterales and other non-fermenting Gram-negative bacteria have become a threat worldwide owing to the frequency of multidrug resistance in these pathogens. On the other hand, efficacious therapeutic options are quickly diminishing. The aims of this study were to describe the susceptibility of 50 multiresistant Gram-negative bacteria, mostly pan-resistant, against old and less-used antimicrobial drugs and to investigate the presence of antimicrobial resistance genes.
A total of 50 genetically distinct isolates were included in this study, including 14 Acinetobacter baumannii (belonging to ST79, ST317, ST835 and ST836), 1 Pseudomonas aeruginosa (ST245), 8 Serratia marcescens and 27 Klebsiella pneumoniae (belonging to ST11, ST340, ST258, ST16, ST23, ST25, ST101, ST234, ST437 and ST442). The isolates were submitted to antimicrobial susceptibility testing and whole-genome sequencing to evaluate lineages and resistance genes.
Our results showed that some strains harboured carbapenemase genes, e.g. bla
mannii, ceftazidime/avibactam against Enterobacterales, and fosfomycin against S. marcescens.The potent aroma compounds in butter from four kinds of Chinese butter hotpot seasoning were first investigated by analyzing the isolates from solid-phase microextraction. A total of 49 aroma compounds were identified, and 23 of them were highly correlated with the aroma profiles of the butter by partial least squares regression analysis. Aroma extract dilution analysis and odor activity value calculations were applied to further reveal the dominant odorants. Fifty-three odorants with flavor dilution factors between 1 and 1024 were identified and OAVs of 17 odorants were greater than 1. Finally, an aroma recombination experiment was prepared by mixing the aroma-active compounds (OAVs > 1), and the aroma profile of the recombination showed good agreement with that of the original sample. Omission tests showed that 2-furfurylthiol, 2-acetylthiazole, anethole, (E)-2-decenal, and 1,8-cineole were the key odorants for the overall aroma of butter.The fatty acid content of flour is an important indicator for determining the deterioration of flour. We propose a novel rapid measurement method for fatty acid content during flour storage based on a self-designed color-sensitive gas sensor array. First, a color-sensitive gas sensor array was prepared to capture the odor changes during flour storage. The sensor features were then optimized using genetic algorithm (GA), ant colony optimization (ACO) and particle swarm optimization (PSO). Finally, back propagation neural network (BPNN) models were established to measure the fatty acid content during flour storage. Experimental results showed that the optimization effects of the three algorithms improved in the following order GA less then ACO less then PSO, for the sensor features optimization. https://www.selleckchem.com/products/MK-1775.html In the validation set, the determination coefficient of the best PSO-BPNN model was 0.9837. The overall results demonstrate that the models established on the optimized features can realize rapid measurements of fatty acid content during flour storage.In bottled wines, haze and turbidity are phenomena to be avoided. Since bentonite fining is a common process to clarify wines removing heat unstable proteins, a theoretical study on the adsorption of three Charged Model Molecules (CMMs, egg albumin, polyphenols and riboflavin) was carried out to deep comprehend this chemical phenomenon. Four bentonites were adopted and finely characterized together with the potential release of Na+ and Ca2+ cations, revealing suitable for RT albumin removal within 120 min. Better results in terms of adsorbed quantity were achieved by adopting 12%v/v EtOH/H2O solvent and by swelling bentonites for 24 h before use. With the most performing sample (Na/Ca_0.27), a comprehensive study on simultaneous adsorption of the three CMMs was performed, resulting in polyphenols adsorption increase due to their interactions with albumin. Notwithstanding the majority of albumin and riboflavin was successfully removed, ca. 40-50% of tested polyphenols was preserved.Cadmium, inorganic arsenic and, potentially, dimethyl arsenic acid are carcinogens widely elevated in rice. Here it was identified that the food-safe and common cadmium chelator citric acid efficiently removed cadmium from intact grain via pre-soaking procedure, while also reducing arsenic species. A twostep pre-soaking stage was developed whereby rice was first incubated, at ambient temperature, in 1 M citric acid for 12 h, and then in 1 M calcium carbonate for another 12 h, the latter step to neutralize pH, followed by cooking. When 10 different individual types of rice were processed in such a way this resulted in removal rates of 79% for cadmium, 81% for inorganic arsenic and a 66% for DMA. The technology is particularly suitable for bulk food processing and could be deployed in the most cadmium and arsenic impacted regions where rice is a staple.Cyclodextrin (CD)-metal-organic frameworks (MOFs) are developed as a new type of food-acceptable multi-porous material, which shows a great potential for controlled volatile compound release. This study aimed to synthesize CD-MOFs from potassium nitrate, crystallized with α-cyclodextrin (α-CD), β-CD or γ-CD, and their complex capacities were further evaluated using menthol encapsulation. Compared with CD, all the CD-MOFs had highly ordered crystal structures and more regular shapes. β-CD-MOF showed better thermal stability, with an initial thermal degradation temperature of 253 °C, higher than the other two CD-MOFs. The CD-MOFs were used for menthol encapsulation and the resulting menthol concentration within the inclusion complexes (ICs) was determined. The menthol concentration in ICs followed the order β-CD-MOF > β-CD > γ-CD-MOF > γ-CD > α-CD ≥ α-CD-MOF. The menthol content and encapsulation efficiency of β-CD-MOF were 21.76% (w/w) and 22.54% (w/w) respectively, significantly higher than those of other reported solid materials, such as amylose, CD and V-type starch.Ochratoxin A (OTA) is a toxic metabolite that is widely distributed in food products. Herein, we proposed a new fluorescent aptasensor for OTA detection by using cascade strand displacement reaction. The binding of OTA and OTA aptamer on magnetic beads surface inhibited its hybridization with complementary DNA, and subsequently initiated the strand displacement reaction that induced amplified fluorescence signal. By tracing fluorescence response, our method demonstrated an improved detection limit of 0.63 ng/mL, a short assay time of 110 min, and a satisfactory detection specificity by using ochratoxin B, aflatoxin B1, and zearalenone as control toxins. Recovery studies were conducted by spiking OTA in real food samples, including white wine, red wine, cereal drink, coffee beverage and tea beverage, and confirmed desirable accuracy and practical applicability of our method. Therefore, our method may have a great potential use in the food quality control in the future.
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