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1.
Food Chem ; 398: 133884, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964575

RESUMO

Development of selective and sensitive methods for the detection of 2, 6-dipicolinic acid (DPA), a biomarker produced by bacterial spores, is of great significance for maintaining public health and food safety. Herein, a ratiometric fluorescence strategy using graphene carbon nitride (g-C3N4) coupled with Eu3+ is designed for the assay of DPA. As the concentration of DPA increases, the emission intensity of g-C3N4 kept constant which acted as a stable internal reference, while the fluorescence of Eu3+ was enhanced obviously due to the antenna effect. The linear calibration ranged from 0.1 to 15 µM with a detection limit of 13 nM was obtained. More Importantly, a paper-based sensor with a smartphone was successfully combined to perform colorimetric and visual detection of DPA in situ. This method has good performance for the detection of DPA, which is expected to broaden the application prospects of preliminary biomarker monitoring.


Assuntos
Antraz , Antraz/diagnóstico , Antraz/microbiologia , Biomarcadores , Európio , Corantes Fluorescentes , Humanos , Nitrilas , Ácidos Picolínicos , Smartphone
2.
Food Chem ; 398: 133795, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987006

RESUMO

This study presents a novel method for predicting the shelf life of pork in real-time based on front-face fluorescence excitation-emission matrices (EEMs). The total viable count (TVC) of bacteria was used as the indicator of microbial spoilage in the pork samples. Modified Gompertz and square root equations were used to establish models for the trends in microbial growth and for predicting the shelf life, the R2 values of the fitting equation at different temperatures were all greater than 0.95. The fluorescence intensity ratio of oxidation product to tryptophan (FOX/Trp) was highly correlated with the quality deterioration of pork and was therefore used to establish a quantitative model of TVC values by linear regression with Rc2 and Rp2 values of 0.914 and 0.906, respectively. The mean absolute errors between the remaining shelf life predicted by fluorescence EEMs and the measured values at three storage temperatures were less than 1 day.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Bactérias/genética , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Modelos Lineares , Carne Vermelha/microbiologia , Suínos , Temperatura
3.
J Hazard Mater ; 441: 129897, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36084469

RESUMO

The co-existence of antibiotics and heavy metals in soil with manure application poses high risk to both environment and human health, and thus effective remediation methods are in urgent need. This study investigated the synergistic effects of electrokinetic remediation (EKR) on antibiotic resistance and arsenic (As) in co-contaminated paddy soils. EKR treatments in soil amended with pig manure (EKR-PD) showed better remediation efficiency compared with that without pig manure. In detail, the content of available As and the abundance of antibiotic-resistant bacteria (ARB) decreased by 25.2 %-41.4 % and 9.5 %-21.1 % after 7-d remediation, respectively, due to a relatively higher current density for EKR-PD. The role of the electric field contributed to 33.9 % of antibiotic degradation. Antibiotic resistance genes (ARGs) with ribosomal-protection and enzymatic-deactivation types were easier to remove, with the removal ratio of 37.8 %-41.6 % in EKR-PD. Brevundimonas was the most significantly different species during remediation. Bacillus and Clostridium_ sensu_stricto_1 were potential host bacteria of ARGs in the electric field. Membrane transport might be an effective strategy for microorganisms to respond to the stress of both electric field and co-contaminated environments. This study supports the potential role of EKR in the co-contamination of heavy metals and antibiotic resistance under manure application.


Assuntos
Arsênio , Metais Pesados , Antagonistas de Receptores de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Antibacterianos/farmacologia , Bactérias/genética , Genes Bacterianos , Humanos , Esterco/microbiologia , Solo , Microbiologia do Solo , Suínos
4.
J Hazard Mater ; 441: 129921, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36103767

RESUMO

Glyphosate will be banned from Europe by the end of 2022, but its widespread use in the last decades and its persistence in the environment require the development of novel remediation processes. In this work, a bacterial consortium was designed de novo with the aim to remove glyphosate from polluted water, supported by the oxygen produced by a microalgal species. To this goal, bioinformatics tools were employed to identify the bacterial strains from contaminated sources (Pseudomonas stutzeri; Comamonas odontotermitis; Sinomonas atrocyanea) able to express enzymes for glyphosate degradation, while the microalga Chlorella protothecoides was chosen for its known performances in wastewater treatment. To follow a bioaugmentation approach, the designed consortium was cultivated in continuous photobioreactors at increasing glyphosate concentrations, from 5 to 50 mg L-1, to boost its acclimation to the presence of the herbicide and its capacity to remove it from water. C. protothecoides tolerance to glyphosate was verified through batch experiments. Remarkably, steady state conditions were reached and the consortium was able to live as a community in the reactor. The consortium activity was validated in both synthetic and real wastewater, where glyphosate concentration was reduced by about 53% and 79%, respectively, without the detection of aminomethylphosphonic acid formation.


Assuntos
Chlorella , Herbicidas , Microalgas , Bactérias/metabolismo , Biodegradação Ambiental , Chlorella/metabolismo , Glicina/análogos & derivados , Herbicidas/metabolismo , Microalgas/metabolismo , Oxigênio/metabolismo , Fotobiorreatores/microbiologia , Águas Residuárias , Água
5.
Food Chem ; 400: 134107, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36087481

RESUMO

This study evaluated the inoculation of Meyerozyma guilliermondii and Bacillus licheniformis, separately or in co-culture, in wet-processed conilon coffee. Wet fermentation was conducted for 48 h. Mesophilic bacteria, lactic acid bacteria, yeasts, and filamentous fungi were counted during fermentation. The inoculation of B. licheniformis and M. guilliermondii stimulated the multiplication of lactic acid bacteria. Acetic, citric, lactic, oxalic, malic, succinic, tartaric acids, glucose, and fructose were identified in all treatments at different concentrations. Methyl salicylate, 2-heptanol, 2-nonanol, and heptanone were found during fermentation. Methylpyrazine, 2,6-dimethylpyrazine, 2,5-dimethylpyrazine, and 3-ethyl-2,5-dimethylpyrazine identified after roasting assigned notes of "almond" and "chocolate" to the beverages. All treatments were classified as "premium," with the B. licheniformis treatment receiving the highest score. Bacillus licheniformis obtained better performance in fermentation, increasing coffee score and producing volatile compounds that provided positive sensory notes to the beverage.


Assuntos
Coffea , Lactobacillales , Bactérias/genética , Café/microbiologia , Frutose , Glucose , Heptanol , Leveduras
6.
Food Chem ; 399: 133989, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36041337

RESUMO

To characterize the involvement of microorganisms in amino acid degradation and fish quality deterioration, three major grass carp spoilage bacteria were artificially inoculated in amino acid solutions (in-vitro) and grass carp flesh (in-situ). Results showed that Pseudomonas putida largely degraded free amino acids and produced 3.78 mM/100 g ammonia in grass carp flesh, relying on its high amino acid deamination1 activity. Aeromonas rivipollensis produced 3-Methyl-butanol and 2-Methyl-butanol through leucine and isoleucine degradation. Shewanella putrefaciens had potent ornithine-decarboxylation activity (423.91 × 10-9 µg/CFU) and released 22.98 mg/kg putrescine in situ. S. putrefaciens could produce more putrescine when cooperating with P. putida through the arginine deiminase pathway. To conclude, the biochemical activities identified through in-vitro tests correlated well with quality changes in inoculated grass carp flesh. The outcomes of this study provided fundamental information on the spoilage mechanisms of freshwater fish and important guidance for the development of quality control strategies.


Assuntos
Carpas , Contaminação de Alimentos , Alimentos Marinhos , Shewanella putrefaciens , Aminoácidos , Animais , Butanóis , Proteínas de Peixes , Putrescina , Alimentos Marinhos/microbiologia
7.
J Environ Sci (China) ; 124: 117-129, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182122

RESUMO

In this study, a modified continuous-flow nitrifying reactor was successfully operated for rapid cultivation of micro-granules and achieving robust nitritation. Results showed that sludge granulation with mean size of ca. 100 µm was achieved within three weeks by gradually increasing settling velocity-based selection pressure from 0.48 to 0.9 m/hr. Though Nitrospira like nitrite-oxidizing bacteria (NOB) were enriched in the micro-granules with a ratio between ammonia-oxidizing bacteria (AOB) and NOB of 5.7%/6.5% on day 21, fast nitritation was achieved within one-week by gradually increasing of influent ammonium concentration (from 50 to 200 mg/L). Maintaining ammonium in-excess was the key for repressing NOB in the micro-granules. Interestingly, when the influent ammonium concentration switched back to 50 mg/L still with the residual ammonium of 15-25 mg/L, the nitrite accumulation efficiency increased from 90% to 98%. Experimental results suggested that the NOB repression was intensified by both oxygen and nitrite unavailability in the inner layers of micro-granules. Unexpectedly, continuous operation with ammonium in excess resulted in overproduction of extracellular polysaccharides and overgrowth of some bacteria (e.g., Nitrosomonas, Arenimonas, and Flavobacterium), which deteriorated the micro-granule stability and drove the micro-granules aggregation into larger ones with irregular morphology. However, efficient nitritation was stably maintained with extremely high ammonium oxidation potential (> 50 mg/g VSS/hr) and nearly complete washout of NOB was obtained. This suggested that smooth and spherical granule was not a prerequisite for achieving NOB wash-out and maintaining effective nitritation in the granular reactor. Overall, the micro-granules exhibited a great practical potential for high-rate nitritation.


Assuntos
Compostos de Amônio , Nitritos , Amônia , Bactérias , Reatores Biológicos/microbiologia , Nitrogênio , Oxirredução , Oxigênio/análise , Esgotos/microbiologia
8.
J Environ Sci (China) ; 124: 146-155, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182125

RESUMO

In this study, the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated. The results of the long-term experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity, to reach as high as 84.9%±2.8% TN removal efficiency. Partial denitrification-anammox (PDN/anammox) and denitrification were proposed as the major pathways for nitrogen removal, accounting for 91.3% and 8.7% of the TN removal, respectively. Anammox bacteria could remain active with high abundance of anammox genes to maintain its dominance. Candidatus Kuenenia and Thauera were the predominant genera in the presence of organic matter. Compared with sCOD, batch experiments showed that the introduction of pCOD had a negative effect on nitrogen removal. The contribution of denitrification to nitrogen removal decreased from approximately 14% to 3% with increasing percentage of pCOD. In addition, the analysis result of the process data using an optimized ASM1 model indicated that high percentage of pCOD resulted in serious N2O emission (the peak value up to 0.25 mg N/L), which was likely due to limited mass diffusion and insufficient available carbon sources for denitrification. However, a high sCOD/N ratio was beneficial for alleviating N2O accumulation.


Assuntos
Desnitrificação , Microbiota , Oxidação Anaeróbia da Amônia , Reatores Biológicos/microbiologia , Carbono , Nitrogênio , Oxirredução , Material Particulado , Esgotos/microbiologia , Águas Residuárias
9.
J Environ Sci (China) ; 124: 176-186, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182128

RESUMO

Microbial activity and regrowth in drinking water distribution systems is a major concern for water service companies. However, previous studies have focused on the microbial composition and diversity of the drinking water distribution systems (DWDSs), with little discussion on microbial molecular ecological networks (MENs) in different water supply networks. MEN analysis explores the potential microbial interaction and the impact of environmental stress, to explain the characteristics of microbial community structures. In this study, the random matrix theory-based network analysis was employed to investigate the impact of seasonal variation including water source switching on the networks of three DWDSs that used different disinfection methods. The results showed that microbial interaction varied slightly with the seasons but was significantly influenced by different DWDSs. Proteobacteria, identified as key species, play an important role in the network. Combined UV-chlorine disinfection can effectively reduce the size and complexity of the network compared to chlorine disinfection alone, ignoring seasonal variations, which may affect microbial activity or control microbial regrowth in DWDSs. This study provides new insights for analyzing the dynamics of microbial interactions in DWDSs.


Assuntos
Desinfetantes , Água Potável , Microbiota , Purificação da Água , Biofilmes , Cloro , Desinfecção/métodos , Água Potável/microbiologia , Humanos , Microbiologia da Água , Purificação da Água/métodos , Abastecimento de Água
10.
J Environ Sci (China) ; 124: 655-666, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182171

RESUMO

Stormwater reuse is one of the most important ways to mitigate water resource shortage. However, urban stormwater contains many bacteria species, which threaten the reuse safety. Therefore, stormwater disinfection is highly needed. Although disinfection has been widely conducted in the drinking water and reclaimed water, it is rarely carried out for stormwater. This study collected the roof stormwater and undertook chlorination disinfection. Two typical bacteria, Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) were selected in this study to investigate the disinfection efficiency. It is found that bacteria species present in the stormwater had an important influence on disinfection efficiency while the original stormwater quality did not show an obvious affect. However, when the disinfected stormwater was stored, the stormwater quality was highly variable during its storage process and the variability was affected by bacteria species. The S.aureus containing stormwater showed a high variability of quality and S.aureus significantly regrew. However, the E.coli containing stormwater quality had a relatively low variability and E.coli did not significantly regrew. Additionally, it is noted that after storage, the dissolved form of stormwater was more positive to the freshwater algae's growth while the particulate form (including bacteria and other particulate matters) was less. This implies that a further treatment such as filtration is needed before the stored stormwater is recharged into receiving waters in order to remove particulate forms. These research outcomes can provide useful insight to effective stormwater disinfection and ensure reuse safety.


Assuntos
Desinfecção , Água Potável , Escherichia coli , Água Doce/microbiologia , Qualidade da Água
11.
J Environ Sci (China) ; 124: 769-781, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182182

RESUMO

The seasonal changes in dissolved organic matter (DOM), and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu, China, were investigated from four sampling periods between November 2020 and July 2021. The DOM fluorescence components were identified as protein-like C1, microbial humic-like C2, and terrestrial humic-like C3. The highest total fluorescence intensity (FT) of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains. The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source. The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation. The components of DOM are affected mainly by the dissolved total phosphorus in waters, while the temperature drives the annual cycle of cyanobacteria. The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients, with the strongest release of phosphorus observed during the early growth of cyanobacteria. The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic-inorganic ligands. The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.


Assuntos
Cianobactérias , Lagos , China , Matéria Orgânica Dissolvida , Eutrofização , Lagos/microbiologia , Ligantes , Nutrientes , Fósforo/análise , Espectrometria de Fluorescência
12.
J Environ Sci (China) ; 124: 952-962, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182197

RESUMO

The long-term impact of fulvic acid (FA) on partial nitritation (PN) system was initially examined in this study. The obtained results revealed that the FA lower than 50 mg/L had negligible effect on the nitrite accumulation rate (NAR nearly 100%) and ammonium removal rate (ARR 56.85%), while FA over 50 mg/L decreased ARR from 56.85% to 0.7%. Sludge characteristics analysis found that appropriate FA (<50 mg/L) exposure promoted the settling performance and granulation of PN sludge by removing Bacteroidetes and accumulating Chloroflexi. The analysis of metagenomics suggested that the presence of limited FA (0-50 mg/L) stimulated the generation of NADH, which favors the denitrification and nitrite reduction. The negative impact of FA on the PN system could be divided into two stages. Initially, limited FA (50-120 mg/L) was decomposed by Anaerolineae to stimulate the growth and propagation of heterotrophic bacteria (Thauera). Increasing heterotrophs competed with AOB (Nitrosomonas) for dissolved oxygen, causing AOB to be eliminated and ARR to declined. Subsequently, when FA dosage was over 120 mg/L, Anaerolineae were inhibited and heterotrophic bacteria reduced, resulting in the abundance of AOB recovered. Nevertheless, the ammonium transformation pathway was suppressed because genes amoABC and hao were obviously reduced, leading to the deterioration of reactor performance. Overall, these results provide theoretical guidance for the practical application of PN for the treatment of FA-containing sewage.


Assuntos
Compostos de Amônio , Esgotos , Compostos de Amônio/metabolismo , Bactérias/genética , Bactérias/metabolismo , Benzopiranos , Reatores Biológicos/microbiologia , Metagenômica , NAD/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Oxirredução , Oxigênio/metabolismo , Esgotos/microbiologia
13.
Int J Food Microbiol ; 384: 109979, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36260958

RESUMO

Strawberry fruit is highly susceptible to decay by fungi. The objective of this study was to determine if essential oils (EOs) or nano-emulsions (Nano-EM) of EOs from Thymus vulgaris (Th), Matricaria chamomilla (Mc), Pistacia atlantica (Pa), or Mentha longifolia (Me) could inhibit growth of strawberry spoilage fungi Botrytis cinerea and their effect, if any, on strawberry quality parameters. An In vitro study showed that Th and Me EOs had the same minimal inhibitory concentrations (MIC) of 0.021 % while the MICs for Mc and Pa EOs were 0.9 % and 1.5 %, respectively. Th and Me EOs were used for subsequent experiments. In the second experiment, the application of Th and Me EOs and their nano-EM at 0.021, 0.1, 0.5 and 1 % were studied to control B. cinerea growth on the fruit surface. Nano-EM of EOs had higher antifungal activity in the control of B. cinerea than EOs on fruit surface. Generally, antifungal activity was increased at higher concentrations of Nano-EM, but in the case of EOs, their antifungal activity was not increased by increasing concentration. Nano-EM of EOs with 0.5 % was selected for further study. Finally, the quality changes and postharvest losses of fruit treated with Nano-EM of EOs of Th and Me at 4 °C were studied. The results of third experiment showed that Nano-EM of both EOs reduced microbial load, decay index, weight loss and induced greater firmness, vitamin C, total flavonoid and antioxidant activity in strawberry during storage. NanoEM-ThEO 0.5 % was more effective than NanoEM-MeEO 0.5 % to retain strawberry firmness, vitamin C and total flavonoid.


Assuntos
Fragaria , Óleos Voláteis , Fragaria/microbiologia , Frutas/microbiologia , Óleos Voláteis/farmacologia , Antifúngicos/farmacologia , Botrytis , Ácido Ascórbico/farmacologia , Flavonoides/farmacologia , Doenças das Plantas/microbiologia
14.
Int J Food Microbiol ; 384: 109980, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36270222

RESUMO

Bacteria and filamentous fungi (ff) are commonly encountered in biofilms developed in drinking water (DW) distribution systems (DWDS). Despite their intimate ecological relationships, researchers tend to study bacteria and ff separately. This work assesses the impact of bacteria-ff association in biofilm formation and tolerance to chlorination. One strain of Acinetobacter calcoaceticus isolated from DW was used as a model bacterium. Penicillium brevicompactum and P. expansum isolated from DW were the ff selected. Single species and inter-kingdom adhesion and biofilm formation occurred under two shear stress (τ) conditions (0.05 and 1.6 Pa). The sessile structures were further characterized in terms of biomass production, respiratory activity and structure. The results showed that 1.6 Pa of shear stress and A. calcoaceticus-ff association favoured biofilm production. Inter-kingdom biofilms produced more biomass than A. calcoaceticus single species and reduced A. calcoaceticus susceptibility to disinfection, particularly to high sodium hypochlorite (SHC) concentrations. In addition, P. brevicompactum formed single species biofilms highly resistant to removal and inactivation by SHC. The presence of P. brevicompactum or P. expansum in inter-kingdom biofilms significantly decreased SHC removal and inactivation effects in comparison to the bacterial biofilms alone, proposing that using bacteria to form biofilms representative of DWDS can provide inaccurate conclusions, particularly in terms of biofilm production and susceptibility to disinfection.


Assuntos
Acinetobacter calcoaceticus , Água Potável , Água Potável/microbiologia , Biofilmes , Bactérias , Hipoclorito de Sódio , Fungos
15.
Artigo em Inglês | MEDLINE | ID: mdl-36191806

RESUMO

The α7 subtype of the nicotinic acetylcholine receptor (α7 nAChR: coded by Chrna7) is known to regulate the cholinergic ascending anti-inflammatory pathway. We previously reported that Chrna7 knock-out (KO) mice show depression-like behaviors through abnormal composition of gut microbiota and systemic inflammation. Given the role of subdiaphragmatic vagus nerve in gut-microbiota-brain axis, we investigated whether subdiaphragmatic vagotomy (SDV) could affect depression-like behaviors, abnormal composition of gut microbiota, and microbes-derived metabolites in Chrna7 KO mice. SDV blocked depression-like behaviors and reduced expression of synaptic proteins in the medial prefrontal cortex (mPFC) of Chrna7 KO mice. LEfSe (linear discriminant analysis effect size) analysis revealed that the species Lactobacillus sp. BL302, the species Lactobacillus hominis, and the species Lactobacillus reuteri, were identified as potential microbial markers in the KO + SDV group. There were several genus and species altered among the three groups [wild-type (WT) + sham group, KO + sham group, KO + SDV group]. Furthermore, there were several plasma metabolites altered among the three groups. Moreover, there were correlations between relative abundance of several microbiome and behavioral data (or synaptic proteins). Network analysis showed correlations between relative abundance of several microbiome and plasma metabolites (or behavioral data). These data suggest that Chrna7 KO mice produce depression-like behaviors and reduced expression of synaptic proteins in the mPFC through gut-microbiota-brain axis via subdiaphragmatic vagus nerve.


Assuntos
Eixo Encéfalo-Intestino , Depressão , Animais , Camundongos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Anti-Inflamatórios , Encéfalo , Eixo Encéfalo-Intestino/genética , Eixo Encéfalo-Intestino/fisiologia , Colinérgicos , Depressão/etiologia , Depressão/microbiologia , Modelos Animais de Doenças , Lactobacillus , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microbiota , Fenótipo , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Nervo Vago
16.
Semin Cell Dev Biol ; 134: 69-78, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35459546

RESUMO

The marine green macroalga Ulva (Chlorophyta, Ulvales), also known as sea lettuce, coexists with a diverse microbiome. Many Ulva species proliferate in nature and form green algal blooms ("green tides"), which can occur when nutrient-rich wastewater from agricultural or densely populated areas is flushed into the sea. Bacteria are necessary for the adhesion of Ulva to its substrate, its growth, and the development of its blade morphology. In the absence of certain bacteria, Ulva mutabilis develops into a callus-like morphotype. However, with the addition of the necessary marine bacteria, the entire morphogenesis can be restored. Surprisingly, just two bacteria isolated from U. mutabilis are sufficient for inducing morphogenesis and establishing the reductionist system of a tripartite community. While one bacterial strain causes algal blade cell division, another causes the differentiation of basal cells into a rhizoid and supports cell wall formation because of a low concentration of the morphogen thallusin (below 10-10 mol/L). This review focuses on the research conducted on this topic since 2015, discusses how U. mutabilis has developed into a model organism in chemical ecology, and explores the questions that have already been addressed and the perspectives that a reductionist model system allows. In particular, the field of systems biology will achieve a comprehensive, quantitative understanding of the dynamic interactions between Ulva and its associated bacteria to better predict the behavior of the system as a whole. The reductionist approach has enabled the study of the bacteria-induced morphogenesis of Ulva. Specific questions regarding the optimization of cultivation conditions as well as the yield of raw materials for the food and animal feed industries can be answered in the laboratory and through applied science. Genome sequencing, the improvement of genetic engineering tools, and the first promising attempts to leverage macroalgae-microbe interactions in aquaculture make this model organism, which has a comparatively short parthenogenetic life cycle, attractive for both fundamental and applied research. The reviewed research paves the way for the synthetic biology of macroalgae-associated microbiomes in sustainable aquacultures.


Assuntos
Clorófitas , Alga Marinha , Ulva , Ulva/metabolismo , Ulva/microbiologia , Alga Marinha/microbiologia , Aquicultura , Morfogênese , Bactérias
17.
Vet Clin North Am Small Anim Pract ; 53(1): 155-173, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36270845

RESUMO

The purpose of this review is to familiarize clinical pathologists and clinicians with the cytomorphologic features associated with deep mycoses in dogs and cats. The goals are to develop a more unified approach to the description and interpretation of fungal cytomorphology and to facilitate the categorization of fungi that do not produce unique morphologic structures in tissue.


Assuntos
Doenças do Gato , Doenças do Cão , Micoses , Gatos , Cães , Animais , Doenças do Gato/diagnóstico , Doenças do Cão/diagnóstico , Micoses/veterinária , Micoses/microbiologia
18.
Bioresour Technol ; 367: 128253, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334868

RESUMO

Improper disposal of antibiotic fermentation dregs poses a risk of releasing antibiotics and antibiotic resistant bacteria to the environment. Therefore, this study evaluated the effects of biochar addition to lincomycin fermentation dregs (LFDs) composting. Biochar increased compost temperature and enhanced organic matter decomposition and residual antibiotics removal. Moreover, a 1.5- to 17.0-fold reduction in antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) was observed. Adding biochar also reduced the abundances of persistent ARGs hosts (e.g., Streptomyces, Pseudomonas) and ARG-related metabolic pathways and genes (e.g., ATP-binding cassette type-2 transport, signal transduction and multidrug efflux pump genes). By contrast, compost decomposition improved due to enhanced metabolism of carbohydrates and amino acids. Overall, adding biochar into LFDs compost reduced the proliferation of ARGs and enhanced microbial community metabolism. These results demonstrate that adding biochar to LFDs compost is a simple and efficient way to decrease risks associated with LFDs composting.


Assuntos
Compostagem , Lincomicina , Antibacterianos/farmacologia , Fermentação , Esterco/microbiologia , Genes Bacterianos/genética , Resistência Microbiana a Medicamentos/genética
19.
Bioresour Technol ; 367: 128234, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334867

RESUMO

Acid-pretreated pistachio shells were used as carbon sources to investigate the effects of carbon source dosage on simultaneous nitrogen and phosphorus removal under different carbon/nitrogen (C/N) ratios (7, 9, and 11). Results showed that C/N was positively correlated with mixed liquor suspended solids (MLSS) (R2 = 0.998, p < 0.01) and f value (R2 = 0.975, p < 0.05). Moreover, it was negatively correlated with the sludge volume index (SVI) (R2 =  - 0.959, p < 0.05). C/N was also significantly negatively related to chemical oxygen demand removal rate (R2 =  - 0.986, p < 0.05) and positively related to ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) removal rate (p < 0.05), the correlation coefficients were 0.992, 0.990 and 0.994, respectively. In the reactor with C/N of 11, the MLSS concentration and f value were the highest, the SVI was the lowest, and the removal efficiencies of NH4+-N (85.49 % ± 1.96 %), TN (84.19 % ± 1.42 %) and TP (94.10 % ± 1.67 %) were the highest. Furthermore, the relative abundance of denitrifying bacteria was the highest in the reactor. The abundance of nitrifying bacteria and phosphorus-removal bacteria was also relatively high.


Assuntos
Pistacia , Águas Residuárias , Fósforo , Nitrogênio , Carbono , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Bactérias , Desnitrificação
20.
Bioresour Technol ; 367: 128254, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334870

RESUMO

For solving the challenge of difficult nutrient removal, high running cost and CO2 emission at low carbon-to-nitrogen (C:N) ratio, Bi-Bio-Selector for nitrogen and phosphorus removal (BBSNP) process was developed. Under parallel operation conditions, full-scale BBSNP was less influence by low C:N ratio (3.5-2) than Anaerobic-anoxic-aerobic (AAO) and achieved better nitrogen removal performance. The mechanism of performance advantage in BBSNP was analyzed by mass balance and high throughout sequencing. It demonstrated BBSNP developed unique microbial community at C:N ratio of 2. Higher abundance of Saccharibacteria, Ferruginibacter, Ottowia, Dokdonella, Candidatus_Nitrotoga and Nitrospira in BBSNP was responsible for better chemical oxygen demand (COD) utilization efficiency, denitrification, denitrifying phosphorus removal and nitrification. Meanwhile, under low C:N ratio, BBSNP could save 10% organic carbon and 15% oxygen requirement, reduce 53% running cost and 21% CO2 emission, which had practical value in relieving energy crisis and carbon emission of wastewater treatment plants (WWTPs).


Assuntos
Nitrogênio , Águas Residuárias , Carbono , Desnitrificação , Eliminação de Resíduos Líquidos , Dióxido de Carbono , Reatores Biológicos/microbiologia , Nitrificação , Fósforo , Nutrientes , Bactérias , Esgotos
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