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1.
Microorganisms ; 12(9)2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39338533

RESUMO

The composition of the vaginal microbiota prior to an IVF/IVF-ICSI treatment can predict the chance of achieving a pregnancy. To improve clinical applicability and be more patient-friendly, the self-collection of vaginal samples would be preferable. However, the reliability of patient-collected samples compared to physician-collected samples remains unclear. This study compares microbiome outcomes from patient-collected versus physician-collected vaginal samples. This is a prospective pilot study consisting of two cohorts: Cohort I involved patient self-sampling of the vagina, followed by a physician-collected vaginal swab, while Cohort II involved the reversed order of collection. The interspace profiling (IS-Pro) technique was used to analyze the microbiota composition in all samples. From May 2021 to March 2022, a total of 444 samples were collected from n = 222 patients (aged 21-44 years), with Cohort I (n = 109) and Cohort II (n = 113). The vaginal microbiome composition of both cohorts was highly similar, regardless of the sampling order, with a mean cosine similarity of 0.93 (95% CI 0.91, 0.95) in Cohort I and 0.94 (95% CI 0.92, 0.96) in Cohort II. Furthermore, ANOVA analysis revealed no significant differences in bacterial species abundance between physician- and patient-collected samples, nor between first and second sample collections. The self-collection of vaginal samples can be considered comparable to physician-collected samples and indicates a more patient-friendly and convenient collection of the vaginal microbiome in an outpatient clinical setting.

2.
Indian J Med Microbiol ; 52: 100733, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39322183

RESUMO

PURPOSE: Donor human milk (DHM) from milk banks provides vital nutrition to vulnerable infants. Understanding its microbial profile and antimicrobial resistance patterns is crucial for ensuring its safety and efficacy. This study aimed to profile the microbial composition, detect antibiotic resistance, and identify the presence of mecA gene in Staphylococcal strains from DHM samples. MATERIALS AND METHOD: A total of 151 DHM samples were collected from a regional human milk bank in North India. Microbial identification was performed using MALDI TOF MS, and antimicrobial susceptibility testing was conducted using the disc diffusion method. Molecular methods, including PCR, were employed for mecA gene detection. RESULTS: The study revealed a diverse microbial profile, with Staphylococcus species being predominant. Acinetobacter and Pseudomonas species were also prevalent, raising concerns due to their association with healthcare-associated outbreaks. High rates of antibiotic resistance were observed across both Gram-positive and Gram-negative bacteria, with resistance to commonly used antibiotics such as penicillin, clindamycin, erythromycin, and ceftriaxone. The mecA gene, associated with methicillin resistance, was detected in a significant proportion of Staphylococcal isolates. CONCLUSION: The study underscores the importance of rigorous microbial analysis and antimicrobial susceptibility testing in assessing the safety of DHM. The presence of diverse microbial species, including antibiotic-resistant strains and the mecA gene in Staphylococcal strains, emphasizes the need for stringent hygiene practices and continuous surveillance in milk banks. Implementing comprehensive screening protocols and adhering to best practices in milk handling and pasteurization are crucial for safeguarding the health of vulnerable infants reliant on donor milk.

3.
Sci Total Environ ; 954: 176381, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39304149

RESUMO

This study investigates the performance and microbial community dynamics in two partial denitrification/anammox (PD/A) reactors with different influent wastewater compositions (differ in the presence/absence of NO2-) subjected to a controlled temperature gradient reduction from mesophilic (30 °C) to room temperature (20.92 °C) over 76 days. Two lab-scale PD/A reactors (R1 and R2), both operated with a total inorganic nitrogen (TIN) concentrations of 70 mg N/L. R1 maintained a NH4+/NO2-/NO3- ratio of 3:3:1 and a COD/NO3- ratio of 2.0, while R2 had an NH4+/NO3- ratio of 3:4, and COD/NO3- ratios of 2.0 and 2.5. Our findings reveal distinct responses to the temperature transitions: the optimization of the NH4+/NO2-/NO3- ratio at 3:3:1 facilitated more stable nitrogen removal as temperatures decreased. This stability can be attributed to the enhanced synchronization between anammox bacteria and denitrifiers, promoting a balanced bioconversion process that is less susceptible to temperature-induced disruptions. Notably, the specific anammox activity (SAA) in both reactors declined linearly with the decrease in temperature, but the relative abundance of anammox bacteria (Ca. Brocadia) in R1 increased from 2.1 % to 9.7 %. Furthermore, the percentage of anammox-related key genes was higher in R1 than in R2, suggesting a microbial mechanism underlying the stable performance of R1. These results underscore the significant impact of influent nitrogen composition on PD/A performance amid temperature gradients and highlight the critical role of optimizing influent ratios for maintaining efficient nitrogen removal. This study offers valuable insights into enhancing the stability of PD/A systems under varying thermal conditions.

4.
Anal Biochem ; 695: 115638, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39127328

RESUMO

Phospholipid fatty acid (PLFA) analysis is used for characterizing microbial communities based on their lipid profiles. This method avoids biases from PCR or culture, allowing data collection in a natural state. However, PLFA is labor-intensive due to lipid fractionation. Simplified ester-linked fatty acid analysis (ELFA), which skips lipid fractionation, offers an alternative. It utilizes base-catalyzed methylation to derivatize only lipids, not free fatty acids, and found glycolipid and neutral lipid fractions are scarcely present in most bacteria, allowing lipid fractionation to be skipped. ELFA method showed a high correlation to PLFA data (r = 0.99) and higher sensitivity than the PLFA method by 1.5-2.57-fold, mainly due to the higher recovery of lipids, which was 1.5-1.9 times higher than with PLFA. The theoretical limit of detection (LOD) and limit of quantification (LOQ) for the ELFA method indicated that 1.54-fold less sample was needed for analysis than with the PLFA method. Our analysis of three bacterial cultures and a simulated consortium revealed the effectiveness of the ELFA method by its simple procedure and enhanced sensitivity for detecting strain-specific markers, which were not detected in PLFA analysis. Overall, this method could be easily used for the population analysis of synthetic consortia.


Assuntos
Ésteres , Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/análise , Ácidos Graxos/química , Fosfolipídeos/análise , Fosfolipídeos/química , Ésteres/análise , Ésteres/química , Bactérias/metabolismo , Limite de Detecção
5.
Int Ophthalmol ; 44(1): 308, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958789

RESUMO

PURPOSE: This study aimed to investigate the demographics, clinical characteristics, and management outcomes of patients with acute infectious endophthalmitis (AIE). METHODS: This retrospective chart review was conducted on all patients admitted with the clinical diagnosis of infectious endophthalmitis from 2017 to 2022. Demographic data, patients' clinical characteristics, the type of acute infectious endophthalmitis (post-operative, post-traumatic, bleb-associated, and endogenous endophthalmitis), the type of surgical procedure in the post-operative cases, the microbiologic analysis results of vitreous samples, therapeutic measures, and visual outcomes of patients were recorded. RESULTS: In this study, 182 participants, including 122 male (67%) and 60 (33%) female, were involved. The mean age of patients was 54.56 ± 21 years, with a range of 1-88 years old. The most prevalent type of AIE was post-operative (59.9%), followed by endogenous (19.2%), post-traumatic (17%), and bleb-associated (3.8%). The most common type of intraocular surgery in the post-operative subgroups of AIE patients was phacoemulsification (57.8%). The median (interquartile range) of the primary and final BCVA of patients was 1.5 (1.35, 1.85) and 0.65 (0.35, 1.35), respectively. Vitreous haziness grade (OR, 2.89; 95% CI, 1.11-5.74; p = 0.009) and the primary VA (OR, 60.34; 95% CI, 2.87-126.8; p = 0.008) revealed statistical significance for final vision loss. CONCLUSION: AIE is a devastating condition with poor visual outcomes, which presents with acute inflammatory signs and symptoms regardless of its type. However, prompt and appropriate treatment leads to visual recovery to a functional level in many patients.


Assuntos
Endoftalmite , Infecções Oculares Bacterianas , Acuidade Visual , Humanos , Endoftalmite/diagnóstico , Endoftalmite/microbiologia , Endoftalmite/epidemiologia , Endoftalmite/terapia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Adulto , Idoso de 80 Anos ou mais , Adolescente , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/microbiologia , Infecções Oculares Bacterianas/epidemiologia , Infecções Oculares Bacterianas/terapia , Adulto Jovem , Doença Aguda , Criança , Pré-Escolar , Lactente , Antibacterianos/uso terapêutico , Corpo Vítreo/microbiologia , Corpo Vítreo/patologia , Vitrectomia/métodos
6.
Environ Health Insights ; 18: 11786302241249844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751904

RESUMO

Underground water quality can be affected by natural or human-made influences. This study investigates how the management and characteristics of hand-dug wells impact water quality in 3 suburbs of Kumasi, Ghana, using a combination of qualitative and quantitative research methods. Descriptive analysis, including frequency and percentages, depicted the demographic profiles of respondents. Box plot diagrams illustrated the distribution of physicochemical parameters (Total Dissolved Solid [TDS], Electrical Conductivity [EC], Turbidity, Dissolved Oxygen [DO], and Temperature). Factor analysis evaluated dominant factors among these parameters. Cluster analysis (hierarchical clustering) utilized sampling points as variables to establish spatial variations in water physicochemical parameters. Cramer's V correlation test explored relationships between demographic variables and individual perceptions of water management. One-way ANOVA verified significant mean differences among the physicochemical parameters. Logistic regression models assessed the influence of selected well features (e.g., cover and apron) on TDS, pH, Temperature, Turbidity, and DO. The findings revealed that proximity to human settlements affects water quality, and increasing turbidity is associated with unmaintained covers, significantly impacting water quality (P < .05). Over 80% of wells were located within 10 to 30 m of pollution sources, with 65.63% situated in lower ground and 87.5% being unmaintained. Other significant contamination sources included plastic bucket/rope usage (87.50%), defective linings (75%), and apron fissures (59.37%). Presence of E. coli, Total coliform, and Faecal coliform rendered the wells unpotable. Factor analysis attributed 90.85% of time-based and spatial differences to organic particle decomposition factors. However, Cramer's V correlation analysis found establishing association between demographic factor associations with individual perceptions of hand-dug well management difficult. It is encouraged to promote hand-dug well construction and maintenance standards to ensure that wells are properly built and protected from contamination sources.

7.
Environ Res ; 252(Pt 3): 119013, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701890

RESUMO

Both ultrasound and sludge retention time (SRT) enable the in-situ sludge reduction during wastewater treatment, but the influence of SRT on ultrasonic lysis - cryptic growth is unclear. This paper researched the influence of different SRTs on sludge lysis - cryptic growth using a sequential bio-reactor (SBR), then explained in details the changes of microorganisms in the SBR. The best SRT for sludge reduction was 30 d, and 47.29% reduction in sludge was achieved. The different SRTs changed the organic matter removal in the wastewater, and the removal rate decreased when SRT exceeded 60 d. The size of the sludge particles varied depending on the SRT, with the smallest size at SRT of 10d being 45.6 µm and the largest size at SRT of 90d being 110.0 µm. SEM showed that the sludge surface changed rough at longer SRT. FTIR and XPS showed notable effect in sludge functional group strength at SRT of 30 d. Extracellular polymeric substance (EPS) reduced the most at SRT of 30 d. The microbial communities of sludge varied with the SRT, and the unique main genus at SRT of 5, 15, 30 and 90 d were C10-SB1A, Lactococcus, Propioniciclava, Lactococcus, respectively. Furthermore, the SRT changed relative abundance of enzymes concerned with metabolism of carbon, nitrogen, and phosphorus. Similarly, SRT changed the metabolic rate, and the metabolic rate of carbon, nitrogen and phosphorus was best at SRT of 30 d.


Assuntos
Reatores Biológicos , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Microbiota , Bactérias/metabolismo , Ondas Ultrassônicas
8.
Nanotechnology ; 35(32)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38701766

RESUMO

One of the global challenges for living things is to provide pollution and harmful microbes-free environment. In this study, magnetically retrievable spinel-structured manganese zinc ferrite (Mn0.5Zn0.5Fe2O4) (MZF) was synthesized by a facile solvothermal method. Further, the MZF with different weight percentages (10 wt%, 50 wt%, and 80 wt%) were supported on reduced graphene oxide (rGO). The phase purity and morphology of MZF and MZF/rGO nanocomposite were confirmed by x-ray diffraction technique and scanning electron microscopy, respectively. The Fourier transform infrared spectroscopy, Raman, UV-visible spectroscopy, and thermogravimetric analyses of the as-synthesized nanocomposites were examined for the detection of various chemical groups, band gap, and thermal properties, respectively. The MZF/rGO nanocomposite exhibited significant antibacterial and antifungal activity againstEggerthella lenta, Enterococcus faecalis, Klebsiella pneumonia, Pseudomonas aeruginosa,andCandida albicanscompared to bare MZF and rGO. The high surface area of rGO plays a crucible role in antimicrobial analysis. Additionally, the antibacterial and antifungal activity is compared by synthesizing various metal ferrites such as MnFe2O4, ZnFe2O4, and Fe3O4. The 50 wt% MZF/rGO nanocomposite exhibits significantly high antibacterial activity. However, 10 wt% MZF/rGO nanocomposite shows good antifungal activity than Fe3O4, MnFe2O4, ZnFe2O4, MnZnFe2O4, 50 wt%, and 80 wt% MZF/rGO nanocomposites. These findings suggest that the prepared ferrite nanocomposites hold promise for microbial inhibition.


Assuntos
Bactérias , Compostos Férricos , Fungos , Grafite , Nanocompostos , Grafite/química , Grafite/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Nanocompostos/química , Fungos/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antifúngicos/farmacologia , Antifúngicos/química , Zinco/química , Zinco/farmacologia , Óxido de Alumínio , Óxido de Magnésio
9.
J Pharm Bioallied Sci ; 16(Suppl 1): S41-S45, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595613

RESUMO

The demand for accurate, faster, and inexpensive sequencing of deoxyribonucleic acid (DNA) is increasing and is driving the emergence of next-generation sequencing (NGS) technologies. NGS can provide useful insights to help researchers and clinicians to develop the right treatment options. NGS has wide applications in novel fields in biology and medicine. These technologies are of great aid to decode mysteries of life, to improve the quality of crops to detect the pathogens, and also useful in improving life qualities. Thousands to millions of molecules can be sequenced simultaneously in parallel using various NGS methods. NGS can identify and characterize the microbial species more comprehensively than culture-based methods. Recently, the NGS approach has been used for oral microbial analysis.

10.
Water Res ; 257: 121662, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38678834

RESUMO

This study investigated the impact of two low-temperature thermal pre-treatments on continuous anaerobic reactors' performance, sequentially fed with sludge of different total solids content (∼3 % and ∼6 %) and subjected to progressively increasing Organic Loading Rates (OLR) from 1.0 to 2.5 g volatile solids/(LReactor⋅day). Assessing pre-treatments' influence on influent sludge characteristics revealed enhanced organic matter hydrolysis, facilitating sludge solubilization and methanogenesis; volatile fatty acids concentration also increased, particularly in pre-treated sludge of ∼6 % total solids, indicating improved heating efficiency under increased solids content. The reactor fed with sludge pre-treated at 45 °C for 48 h and 55 °C for an extra 48 h exhibited the highest methane yield under all applied OLRs, peaking at 240 ± 3.0 mL/g volatile solids at the OLR of 2.5 g volatile solids/(LReactor⋅day). 16S rRNA gene sequencing demonstrated differences in the reactors' microbiomes as evidence of sludge thickening and the different pre-treatments applied, which promoted the release of organic matter in diverse concentrations and compositions. Finally, the microbial analysis revealed that specific foam-related genera increased in abundance in the foam layer of reactors' effluent bottles, dictating their association with the sludge foaming incidents that occurred inside the reactors during their operation at 2.0 g volatile solids/(LReactor⋅day).


Assuntos
Reatores Biológicos , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , RNA Ribossômico 16S/genética , Metano/metabolismo , Ácidos Graxos Voláteis/metabolismo , Anaerobiose , Microbiota
11.
Bioresour Technol ; 401: 130739, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670291

RESUMO

A modified biodegradable plastic (PLA/PBAT) was developed by through covalent bonding with proteinase K, porcine pancreatic lipase, or amylase, and was then investigated in anaerobic co-digestion mixed with food waste. Fluorescence microscope validated that enzymes could remain stable in modified the plastic, even after co-digestion. The results of thermophilic anaerobic co-digestion showed that, degradation of the plastic modified with Proteinase K increased from 5.21 ± 0.63 % to 29.70 ± 1.86 % within 30 days compare to blank. Additionally, it was observed that the cumulative methane production increased from 240.9 ± 0.5 to 265.4 ± 1.8 mL/gVS, and the methane production cycle was shortened from 24 to 20 days. Interestingly, the kinetic model suggested that the modified the plastic promoted the overall hydrolysis progression of anaerobic co-digestion, possibly as a result of the enhanced activities of Bacteroidota and Thermotogota. In conclusion, under anaerobic co-digestion, the modified the plastic not only achieved effective degradation but also facilitated the co-digestion process.


Assuntos
Plásticos Biodegradáveis , Metano , Anaerobiose , Metano/metabolismo , Plásticos Biodegradáveis/química , Biodegradação Ambiental , Lipase/metabolismo , Suínos , Animais , Alimentos , Resíduos , Amilases/metabolismo , Cinética , Hidrólise , Eliminação de Resíduos/métodos , Perda e Desperdício de Alimentos
12.
Water Res ; 254: 121416, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489851

RESUMO

Sulfonamides are applied worldwide as antibiotics. They are emerging contaminants of concern, as their presence in the environment may lead to the spread of antibiotic resistance genes. Sulfonamides are present in groundwater systems, which suggest their persistence under certain conditions, highlighting the importance of understanding natural attenuation processes in groundwater. Biodegradation is an essential process, as degradation of sulfonamides reduces the risk of antibiotic resistance spreading. In this review, natural attenuation, and in particular assessment of biodegradation, is evaluated for sulfonamides in groundwater systems. The current knowledge level on biodegradation is reviewed, and a scientific foundation is built based on sulfonamide degradation processes, pathways, metabolites and toxicity. An overview of bacterial species and related metabolites is provided. The main research effort has focused on aerobic conditions while investigations under anaerobic conditions are lacking. The level of implementation in research is laboratory scale; here we strived to bridge towards field application and assessment, by assessing approaches commonly used in monitored natural attenuation. Methods to document contaminant mass loss are assessed to be applicable for sulfonamides, while the approach is limited by a lack of reference standards for metabolites. Furthermore, additional information is required on relevant metabolites in order to improve risk assessments. Based on the current knowledge on biodegradation, it is suggested to use the presence of substituent-containing metabolites from breakage of the sulfonamide bridge as specific indicators of degradation. Microbial approaches are currently available for assessment of microbial community's capacities, however, more knowledge is required on indigenous bacteria capable of degrading sulfonamides and on the impact of environmental conditions on biodegradation. Compound specific stable isotope analysis shows great potential as an additional in situ method, but further developments are required to analyse for sulfonamides at environmentally relevant levels. Finally, in a monitored natural attenuation scheme it is assessed that approaches are available that can uncover some processes related to the fate of sulfonamides in groundwater systems. Nevertheless, there are still unknowns related to relevant bacteria and metabolites for risk assessment as well as the effect of environmental settings such as redox conditions. Alongside, uncovering the fate of sulfonamides in future research, the applicability of the natural attenuation documentation approaches will advance, and provide a step towards in situ remedial concepts for the frequently detected sulfonamides.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Sulfonamidas , Poluentes Químicos da Água/análise , Sulfanilamida/análise , Sulfanilamida/metabolismo , Antibacterianos/metabolismo , Biodegradação Ambiental , Água Subterrânea/microbiologia , Bactérias/metabolismo
13.
Sci Total Environ ; 926: 171980, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38537814

RESUMO

Granular activated carbon (GAC), a porous carbon-based material, provides increased attachment space for functional microorganisms and enhances nitrogen removal by facilitating extracellular electron transfer in the anammox process. This study investigates the effects of GAC on the biosynthesis of microbial extracellular secretions (MESs) and explores the roles of these secretions in anammox activities. Four lab-scale reactors were operated: two downstream UASB reactors (D1 and D2) receiving effluents from the upstream UASB reactors (U1: no-GAC, U2: yes-GAC). Our results indicate that MESs were enhanced with the addition of GAC. The effluent from U2 exhibited a 59.62 % higher amino acid content than that from U1. These secretions contributed to an increase in the nitrogen loading rate (NLR) in the downstream reactors. Specifically, NLR in D1 increased from 130.5 to 142.7 g N/m3/day, and in D2, it escalated from 137.5 to 202.8 g N/m3/day, likely through acting as cross-feeding substrates or vital nutrients. D2 also showed increased anammox bacterial activity, enriched Ca. Brocadia population and hao gene abundance. Furthermore, this study revealed that D2 sludge has significantly higher extracellular polymeric substances (EPS) (48.71 mg/g VSS) and a larger average granule size (1.201 ± 0.119 mm) compared to D1 sludge. Overall, GAC-stimulated MESs may have contributed to the enhanced performance of the anammox process.


Assuntos
Carvão Vegetal , Esgotos , Esgotos/microbiologia , Carvão Vegetal/metabolismo , Oxidação Anaeróbia da Amônia , Reatores Biológicos/microbiologia , Bactérias/metabolismo , Anaerobiose , Nitrogênio/metabolismo , Oxirredução
14.
Chemosphere ; 354: 141660, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462181

RESUMO

Production of medium-chain fatty acids (MCFAs) from sewage sludge has dual effects on valuable sludge disposal and renewable energy generation, while low efficiency limits its application. Biochar addition is considered an effective method to improve MCFAs production. In this study, the influence of biochar adding strategies (i.e., adding biochar in acidification or chain elongation (CE) processes) on MCFAs production was explored. Results showed that by adding biochar in the acidification process, MCFAs accumulation increased by over 114%, accompanied by the highest carbon conversion efficiency (134.66%) and electron transfer efficiency of MCFAs (94.22%) by the terminal CE. Adding biochar before the acidification process better enriched CE bacteria (e.g., Paraclostridium) and strengthened the dominant metabolic pathway. In contrast, the biochar added before the CE process priorly enriched the bacteria capable of degrading organics, like unclassified_f__Dysgonomonadaceae, norank_f__norank_o__OPB41, and Acetobacterium. The differences in excessive ethanol oxidation and short-chain fatty acids accumulation induced by varied adding strategies might be responsible for this.


Assuntos
Carvão Vegetal , Ácidos Graxos , Esgotos , Esgotos/microbiologia , Anaerobiose , Ácidos Graxos Voláteis , Fermentação
15.
Int J Biol Macromol ; 263(Pt 2): 129991, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38331078

RESUMO

This study developed a composite film for packaging refrigerated common carp fillets using carboxymethyl cellulose (CMC) (1.5 % w/v)/Myrrh gum (MG) (0.25 % w/v) base with the addition of titanium dioxide nanoparticles (TiO2 NPs) (0.25 %, 0.5 %, and 1 %) and Dill essential oil (DEO) (1.5 %, 2.25 %, and 3 %). The film was produced using a casting method and optimized for mechanical and barrier properties. The incorporation of DEO and TiO2 NPs into CMC/MG composite films significantly reduced moisture content (MC) and water vapor permeability (WVP), improved their tensile strength (TS), and increased their antimicrobial and antioxidant properties. Moreover, MG can improve the physicomechanical properties of the CMC/MG composite films. The film components had good compatibility without significant aggregation or cracks. In conclusion, the optimized CMC/MG (1.5 %/0.25 %) film containing TiO2 NPs (0.5 %), and DEO (2.25 %) has the best overall performance and can be a good source for making edible film. Functionally, this bioactive nanocomposite film significantly increased the shelf life of refrigerated fish fillet samples for 12 days by inhibiting microbial growth and reducing the oxidation rate compared to the control sample. The knowledge obtained from this study can guide the development of bio-nanocomposite and biodegradable food packaging films based on CMC/MG to increase the shelf life of food products and environmental protection.


Assuntos
Anethum graveolens , Carpas , Commiphora , Nanocompostos , Nanopartículas , Óleos Voláteis , Resinas Vegetais , Animais , Carboximetilcelulose Sódica/farmacologia , Carne , Embalagem de Alimentos/métodos , Óleos Voláteis/farmacologia
16.
Water Res ; 249: 120948, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064787

RESUMO

Scientists have been focusing on applying more natural processes instead of industrial chemicals in drinking water treatment to achieve the purpose of carbon emissions reduction. In this study, we shortened the infiltration range of riverbank filtration, a natural water purification process, to form the short-distance riverbank filtration (sRBF) which retained its ability in water quality improvement and barely influenced the groundwater environment, and integrated it with ultrafiltration (UF) to form a one-step sRBF-UF system. This naturalness-artificiality combination could realize stable contaminants removal and trans-membrane pressure (TMP) increase relief for over 30 days without dosing chemicals. Generally, both sRBF and UF played the important role in river water purification, and the interaction between them made the one-step sRBF-UF superior in long-term operation. The sRBF could efficiently remove contaminants (90 % turbidity, 60 % total nitrogen, 30 % ammonia nitrogen, and 25 % total organic carbon) and reduce the membrane fouling potential of river water under its optimum operation conditions, i.e., a hydraulic retention time of 48 h, an operation temperature of 20 °C, and a synergistic filter material of aquifer and riverbank soil. Synergistic adsorption, interception, and microbial biodegradation were proved to be the mechanisms of contaminants and foulants removal for sRBF. The sequential UF also participated in the reduction of impurities and especially played a role in intercepting microbial metabolism products and possibly leaked microorganisms from sRBF, assuring the safety of product water. To date, the one-step sRBF-UF was a new attempt to combine a natural process with an artificial one, and realized a good and stable product quality in long-term operation without doing industrial chemicals, which made it a promised alternative for water purification for cities alongside the river.


Assuntos
Ultrafiltração , Purificação da Água , Membranas Artificiais , Filtração , Carbono , Nitrogênio
17.
Food Chem X ; 20: 101050, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144767

RESUMO

The goal of research was to investigate the impact of nanoliposome and free forms of nettle (Urtica dioica L.) essential oil (EO) on sensory, chemical and microbial properties of minced camel meat during storage at 4 °C. In our investigation, Listeria monocytogenes and Escherichia coli were inoculated into minced camel meat. The outcomes expressed the zeta potential, particle size, polydispersity index and efficiency of encapsulation of prepared nanoliposome were -17.5 mV to -12.8 mV, 143 to 158 nm, 0.77 ± 0.05 to 0.86 ± 0.07 Mw/Mn and 50.26-67.28 %, respectively. Also, according to the microbial analysis, the MIC of EO and nanoliposome-EO (N-EO) for E.coli was 25 ± 2.5 and 25 ± 2.1 mg/mL, respectively, and for L. monocytogenes was 12.5 ± 2.1 and 12.5 ± 2.1 mg/mL, respectively, and the MBC of EO and N-EO for L. monocytogenes was 50 ± 3.1 and 50 ± 3.2 mg/mL, respectively, and for E. coli was 50 ± 2.2 and 50 ± 2.2 mg/mL, respectively. The highest of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assay were detected in the BHT 200 (94.7 ± 2.7 and 95.6 ± 3.2, respectively) and lowest of them were detected NEO1% (33.7 ± 12.2 and 22.37 ± 0.22, respectively). After 18 days, the minimum value of pH was identified in the N-EO 2 % group incubated with L. monocytogenes (with pH = 6.9) and E. coli (with pH = 6.87). Furthermore, after 18 days of storage, the minimum TVB-N (total volatile basic nitrogen) value was observed in the N-EO group (26.89 mg N/100 g) and the maximum TVB-N value was observed in the control group (33.78 mg N/100 g). Finally, the N-EO and control treatment (during the experiment) had the highest and lowest sensory evaluation score, respectively. Finally, the N-EO group got a highest sensory score, whilst the group of control got the lowest acceptance score, after 18 days of storage. Based on the outcomes obtained from this research, using nettle (Urtica dioica L.) EO (in nanoliposome form) increases the storing time of minced camel meat.

18.
Foods ; 12(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38002142

RESUMO

The typical Korean diet contains a significant quantity of doenjang owing to its unique taste and health benefits. However, the presence of anti-nutritional and toxic substances, such as biogenic amines and microbial pathogens, in doenjang has resulted in a loss of revenue and poor consumer health. The present study focused on the identification and quantification of different biogenic amines, pathogenic Bacillus cereus, and yeast counts in 36 doenjang products (designated as De-1 to De-36, 500 g each) procured from the different cottage industries situated in different parts of the Republic of Korea. The results indicated, only three samples were contaminated with B. cereus, exceeding the recommended limit (4 log CFU/g) suggested by the national standards of Korea. A total of six distinct yeasts were identified in different doenjang samples, whose comprehensive enzymatic profiling suggested the absence of harmful enzymes such as N-acetyl-ß-glucosaminidase, α-chymotrypsin, and ß-glucuronidase. The biogenic amines were detected in the range of 67.68 mg/kg to 2556.68 mg/kg and classified into six major groups based on hierarchical cluster analysis. All doenjang samples contained tryptamine, putrescine, cadaverine, histamine, and tyramine, while 94.44% were positive for spermidine and spermine. The results documented the analysis of traditional cottage industry doenjang and suggest the need for constant monitoring to ensure the safety of food for the consumer.

19.
Cureus ; 15(9): e44816, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809176

RESUMO

AIM: To evaluate microspace and microleakage between implant and abutments subjected to pre- and post-calibrated cyclic stress. MATERIALS AND METHODS: Twelve screw-retained implant prostheses with BioHPP polyetheretherketone (PEEK) abutment (Noris Dental Implant System Ltd., Nesher, Israel) (Group I) and 12 screw-retained implant prostheses with computer-assisted design/computer-assisted manufacturing (CAD/CAM) milled zirconia abutment (DentGallop, Houston, TX, USA) (Group II) were connected to their respective implant, and the prosthetic screw was torqued to 30N/cm (Noris). The microspace was evaluated using scanning electron microscopy (SEM; TeScan, Brno, Czech Republic). Twenty-four samples were then induced to cyclic stress (Lokesh Industries, Pune, India) simulating 180 days duration of oral stress. The microspaces (Group IA and Group IIB) were measured post-cyclic stress. Group I and II were again renamed into Group Ia and Group IIb for microbial study. Both implant assemblies were immersed in fresh soybean casein digest broth (SCDB) (Himedia, Mumbai, India) and subsequently inoculated with 1.0µL E. coli suspension (Himedia) at the open end and incubated at 37ºC for seven days. After the incubation period, cellular activity was determined by the spread plate method, and total colony-forming units (CFU) were calculated. The results were evaluated using independent T and Mann-Whitney tests. RESULT: Average and microspace at the implant-abutment junction of Group I samples in the front right was 12.98µm, center 13.76µm, front left 13.22µm, and in Group II samples, the front right was 18.52µm, center 17.84µm, front left 18.58µm.After being subjected to cyclic loading, the mean levels of the vertical microgap for Group IA samples were: in the front right region 10.37µm, in the center 9.34µm, in the front left 10.51µm and in Group IIB samples front right was 14.59µm, center 13.39µm, front left 13.8µm. Independent t-tests showed insignificant differences between the two groups. The median value of microbial leakage of Group Ia samples after cyclic loading was 30 x 103 CFU/ml, and Group IIb samples were 42 x 103 CFU/ml and were significant. CONCLUSION: There was minimal variation in the mean microspace between the BioHPP PEEK abutment and CAD/CAM milled zirconia abutment, and it was insignificant before and after cyclic stress. BioHPP PEEK abutment-titanium implant interfaces showed significantly decreased microbial leakage than CAD/CAM milled zirconia abutment-titanium implant interfaces after cyclic stress.

20.
Environ Sci Pollut Res Int ; 30(49): 108023-108034, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37743451

RESUMO

Polystyrene (PS) and magnetic polystyrene (MPS) materials have been used extensively in wastewater treatment. In this research, a 55-day anaerobic/oxic process was carried out to evaluate the effects of PS and MPS on microorganisms under aerobic and anaerobic conditions. Scanning electron microscopy results revealed differences in the entanglement state of the sludge with the biocarrier due to differences in surface morphology. High-throughput sequencing analysis showed that the microbial communities differed considerably in the presence of PS and MPS addition under both aerobic and anaerobic conditions. The highest abundance and diversity were observed in the PS reactor, with 929 observed species and a PD_whole_tree index of 91.58 under anaerobic conditions. MPS promoted the enrichment of bacteria related to nitrogen recycling such as Nitrospirota which increased from 1.13% in the seeding sludge to 3.48% and 10.07% in the aerobic reactors with PS and MPS, respectively. Moreover, advanced analysis showed that PS inhibited many microbial functions (e.g., protein export, nitrogen metabolism), and MPS alleviated this inhibition. This study provides significant insights into the microbial effects of PS and MPS and may shed light on biocarrier selection in future studies.


Assuntos
Microbiota , Esgotos , Esgotos/microbiologia , Anaerobiose , Poliestirenos/metabolismo , Bactérias/metabolismo , Nitrogênio/análise , Fenômenos Magnéticos , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodos
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