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1.
Phytomedicine ; 129: 155628, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38663117

ABSTRACT

BACKGROUND: Postmenopausal osteoporosis (PMOP) is a systemic bone disease characterized by low bone mass and microstructural damage. Morinda Officinalis (MO) contains various components with anti-PMOP activities. Morinda Officinalis-derived extracellular vesicle-like particles (MOEVLPs) are new active components isolated from MO, and no relevant studies have investigated their anti-osteoporosis effect and mechanism. PURPOSE: To investigate the alleviating effect of MOEVLPs on PMOP and the underlying mechanism. METHODS: Differential centrifugation and ultracentrifugation were used to isolate MOEVLPs from MO. Transmission electron microscopy (TEM), flow nano analyzer, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), agarose gel electrophoresis, and thin-layer chromatography were employed to characterize MOEVLPs. PMOP mouse models were utilized to examine the anti-PMOP effect of MOEVLPs. H&E and immunohistochemical staining were used for drug safety and osteogenic effect assessment. Mouse embryo osteoblast precursor cells (MC3T3-E1) were used in vitro experiments. CCK-8 kit, alizarin red staining, proteomic, bioinformatic analyses, and western blot were used to explore the mechanism of MOEVLPs. RESULTS: In this study, MOEVLPs from MO were successfully isolated and characterized. Animal experiments demonstrated that MOEVLPs exhibited specific femur targeting, were non-toxic to the heart, liver, spleen, lung, kidney, and aorta, and possessed anti-PMOP properties. The ability of MOEVLPs to strengthen bone formation was better than that of alendronate. In vitro experiments, results revealed that MOEVLPs did not significantly enhance osteogenic differentiation in MC3T3-E1 cells. Instead, MOEVLPs promoted the proliferation of MC3T3-E1 cells. Proteomic and bioinformatic analyses suggested that the proliferative effect of MOEVLPs was closely associated with the mitogen-activated protein kinase (MAPK) signaling pathway, particularly the altered expression of cAMP response element-binding protein (CREB) and ribosomal S6 kinase 1 (RSK1). Western blot results further confirmed these findings. CONCLUSION: Our studies successfully isolated high-quality MOEVLPs and demonstrated that MOEVLPs can alleviate PMOP by promoting osteoblast proliferation through the MAPK pathway. MOEVLPs have the potential to become a novel and natural anti-PMOP drug.


Subject(s)
Extracellular Vesicles , MAP Kinase Signaling System , Morinda , Osteoporosis, Postmenopausal , Animals , Morinda/chemistry , Mice , MAP Kinase Signaling System/drug effects , Female , Osteoporosis, Postmenopausal/drug therapy , Osteoblasts/drug effects , Osteogenesis/drug effects , Humans , Disease Models, Animal
2.
Appl Environ Microbiol ; 90(2): e0204723, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38205997

ABSTRACT

The rapid degradation of short-chain fatty acids (SCFAs) is an essential issue of anaerobic digestion (AD), in which SCFA oxidizers could generally metabolize in syntrophy with methanogens. The dynamic responses of active metagenome-assembled genomes to low concentrations of propionate and acetate were analyzed to identify specific syntrophic SCFA oxidizers and their metabolic characteristics in continuous-flow AD systems treating waste activated sludge with and without hydrochar. In this study, hydrochar increased methane production by 19%, possibly due to hydrochar enhancing acidification and methanogenesis processes. A putative syntrophic propionate oxidizer and two acetate oxidizers contributed substantially to the syntrophic degradation of SCFAs, and hydrochar positively regulated their functional gene expressions. A significant relationship was established between the replication rate of SCFA oxidizers and their stimulation-related transcriptional activity. Acetate was degraded in the hydrochar group, which might be mainly through the syntrophic acetate oxidizer from the genus Desulfallas and methanogens from the genus Methanosarcina.IMPORTANCEShort-chain fatty acid (SCFA) degradation is an important process in the methanogenic ecosystem. However, current knowledge of this microbial mechanism is mainly based on studies on a few model organisms incubated as mono- or co-cultures or in enrichments, which cannot provide appropriate evidence in complex environments. Here, this study revealed the microbial mechanism of a hydrochar-mediated anaerobic digestion (AD) system promoting SCFA degradation at the species level and identified key SCFA oxidizing bacteria. Our analysis provided new insights into the SCFA oxidizers involved in the AD of waste activated sludge facilitated by hydrochar.


Subject(s)
Propionates , Sewage , Sewage/microbiology , Anaerobiosis , Ecosystem , Bioreactors/microbiology , Fatty Acids, Volatile , Acetates/metabolism , Oxidation-Reduction , Methane/metabolism
3.
J Inflamm Res ; 16: 4363-4372, 2023.
Article in English | MEDLINE | ID: mdl-37795493

ABSTRACT

All humans are universally affected by inflammatory diseases, and there is an urgent need to identify new anti-inflammatory drugs with good therapeutic benefits and minimal side effects to the organism. Recently, it has been found that plant-derived vesicle-like nanoparticles (PDVLNs) have good biocompatibility, with their active ingredients exhibiting good therapeutic effects on inflammation. They can also be used as drug carriers for targeted delivery of anti-inflammatory drugs. Therefore, PDVLNs represent a popular research area for novel anti-inflammatory drugs. This paper details the origin, biological functions, isolation and purification, and identification of PDVLNs, as well as the therapeutic effects of their intrinsic bioactive components on inflammatory diseases. It also introduces their targets as drug carriers to facilitate the development and application of PDVLNs anti-inflammatory drugs.

4.
Environ Res ; 231(Pt 1): 116183, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37201703

ABSTRACT

The microbial-mediated removal of arsenate by biomineralization received much attention, but the molecular mechanism of Arsenic (As) removal by mixed microbial populations remains to be elucidated. In this study, a process for the arsenate treatment using sulfate-reducing bacteria (SRB) containing sludge was constructed, and the performance of As removal was investigated at different molar ratios of AsO43- to SO42-. It was found that biomineralization mediated by SRB could achieve the simultaneous removal of arsenate and sulfate from wastewater but only occurred when microbial metabolic processes were involved. The reducing ability of the microorganisms for the sulfate and arsenate was equivalent, so the precipitates produced at the molar ratio of AsO43- to SO42-of 2:3 were most significant. X-ray absorption fine structure (XAFS) spectroscopy was the first time used to determine the molecular structure of the precipitates which were confirmed to be orpiment (As2S3). Combined with the metagenomics analysis, the microbial metabolism mechanism of simultaneous removal of sulfate and arsenate by the mixed microbial population containing SRB was revealed, that is, the sulfate and As(V) were reduced by microbial enzymes to produce S2- and As(III) to further form As2S3 precipitates. This research provided a reference and theoretical foundation for the simultaneous removal of sulfate and arsenic mediated by SRB-containing sludge in wastewater treatment.


Subject(s)
Arsenates , Arsenic , Arsenic/metabolism , Water/chemistry , Sewage/microbiology , Biomineralization , Sulfates/chemistry
5.
Sci Total Environ ; 881: 163212, 2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37003342

ABSTRACT

The objective of this study was to conduct a comparative study of the distribution and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in the sewage collection and treatment system of four cities located in the middle and lower reaches of the Yangtze River. The results revealed that the mean concentration of 16 ΣPAHs was higher in the sewer sediments (1489.45 ng·g-1) than in the sewage sludge (781.78 ng·g-1). PAH monomers were detected in all cases, with higher mean Pyr, Chr, BbF and BaP concentrations. PAHs with 4-6 rings were dominant in both sewage sludge and sewer sediment monomer PAHs. With the isomer ratio method and positive definite matrix factor (PMF) method, the results showed that the major sources of PAHs in sewage sludge were petroleum sources, coal tar, and coking activities, whereas PAHs in sewer sediments were primarily from wood combustion, automobile emissions, and diesel engine emissions. Of all the PAH monomers, BaP and DahA had the highest toxic equivalents, although their levels were not the highest. Based on the assessment of ΣPAHs, it was concluded that both sewage sludge and sewer sediments had medium ecological risk. The results of this study provide reference information for the control of PAHs in the wastewater collection and treatment system of the middle and lower reaches of the Yangtze River.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Sewage/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Rivers , Cities , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Geologic Sediments , China , Risk Assessment
6.
J Environ Manage ; 324: 116445, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36352724

ABSTRACT

Pyrolysis of waste sludge in sewage treatment can achieve a substantial reduction in solid waste and obtain sludge-based biochars with multiple functions. However, the electrochemical properties of sludge-derived biochar as electrode modification material and the electrocatalytic ability of biochar-modified electrodes are still unclear. In this study, sludge-based biochars were prepared at various pyrolysis temperatures (400 °C, 500 °C, 600 °C, 700 °C, and 800 °C) and then were cast on glassy carbon electrodes to fabricate composite biochar-electrodes (GC400, GC500, GC600, GC700, and GC800). The results of elemental analysis and Raman spectra showed that sludge-based biochar prepared at higher temperatures exhibited higher aromaticity and degree of defect structures. And the results of cyclic voltammetry and electrochemical impedance spectra confirmed that biochar-modified electrodes prepared at higher temperatures (>600 °C) possessed better electrocatalytic activity and electrochemical stability, and their higher oxygen evolution potential than control test could improve the electrocatalytic efficiency. In the electrocatalytic oxidation of methyl orange, the removal rate with GC800 was the highest, reaching 94.49% within 240 min, and the removal rates with other composite electrodes were 90.61% (GC700) > 86.96% (GC600) > 80.32% (GC). The free radical quenching experiment revealed that the electrocatalytic degradation of methyl orange mainly depended on the indirect oxidation of hydroxyl radicals generated by electrocatalysis, accounting for 81.3% of the removal rate. The biochar-modified electrode not only greatly improved the electrocatalytic ability of the electrode for the degradation of azo dyes, but also achieved the recycling application of products after pyrolysis of sludge waste.


Subject(s)
Charcoal , Sewage , Sewage/chemistry , Charcoal/chemistry , Azo Compounds , Electrodes
7.
Plant Signal Behav ; 17(1): 2129290, 2022 12 31.
Article in English | MEDLINE | ID: mdl-36196516

ABSTRACT

Extracellular vesicles (EVs) are nano-sized membrane vesicles released by various cell types. Mammalian EVs have been studied in-depth, but the role of plant EVs has rarely been explored. For the first time, EVs from Drynariae Rhizoma roots were isolated and identified using transmission electron microscopy and a flow nano analyzer. Proteomics and bioinformatics were applied to determine the protein composition and complete the functional analysis of the EVs. Seventy-seven proteins were identified from Drynariae Rhizoma root-derived EVs, with enzymes accounting for 47% of the proteins. All of the enzymes were involved in important biological processes in plants. Most of them, including NAD(P)H-quinone oxidoreductase, were enriched in the oxidative phosphorylation pathway in plants and humans, and Alzheimer's disease, Huntington's disease, and Parkinson's disease, which are associated with oxidative stress in humans. These findings suggested that EVs from Drynariae Rhizoma roots could alleviate such neurological diseases and that enzymes, especially NAD(P)H-quinone oxidoreductase, might play an important role in the process.


Subject(s)
Extracellular Vesicles , Neurodegenerative Diseases , Polypodiaceae , Computational Biology , Extracellular Vesicles/metabolism , Humans , NAD/metabolism , Neurodegenerative Diseases/metabolism , Oxidoreductases/metabolism , Plant Roots/chemistry , Polypodiaceae/chemistry , Proteomics , Quinones/metabolism
8.
Bioresour Technol ; 362: 127853, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36037839

ABSTRACT

In the context of climate policies that advocate carbon neutrality, carbon emission reduction provides a new restriction in evaluating the waste activated sludge (WAS) treatment technologies and procedures. This review provides an overview of current researches and development efforts in WAS treatment, focusing on the dual attributes of WAS as contaminants and resources. Firstly, the improved technical requirements posed by heavy metals, micro(nano) plastics, or other emerging plastics in WAS are studied. Furthermore, in terms of carbon emission reduction, the applications and limitations of widely deployed WAS treatment technologies are discussed. Based on carbon neutrality requirements, the anaerobic co-digestion and co-pyrolysis technologies are comprehensively discussed from the views of pollutants removing efficiencies, enhancement methods, carbon emissions, and resource recovery. Finally, a workable new route for WAS treatment is proposed for future technological advancement and engineering innovation.


Subject(s)
Sewage , Waste Disposal, Fluid , Carbon , Plastics , Technology , Waste Disposal, Fluid/methods
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 273: 121041, 2022 May 15.
Article in English | MEDLINE | ID: mdl-35228083

ABSTRACT

In order to better understand the bioavailability, toxicity, migration and transformation behaviors of trace metals in river estuary, this study deeply investigated the interactions between organic matters in sediments and trace metals. The results suggested that both protein-like molecules and marine humic acids could react with trace metals (Cu2+ and Cd2+). These two fluorescent substances fixed trace metals through carboxyl group, hydroxyl group, and phenol hydroxyl group, and protein-like molecules were more sensitive than marine humic acids. Moreover, Cu2+ possessed stronger binding ability and more active sites with both protein-like molecules and marine humic acids. Hence, Cd2+ exhibited higher environmental risks due to the higher migration and transformation. The thermodynamic results revealed that the reaction between WEOM and trace metals was spontaneous and exothermic, and low temperature was favorable for immobilization of Cu2+ or Cd2+.This study could help to understand environmental behaviors and impact of trace metals on the sediments of Yangtze River estuary.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , China , Environmental Monitoring , Estuaries , Geologic Sediments/chemistry , Ions , Metals, Heavy/analysis , Rivers/chemistry , Water , Water Pollutants, Chemical/analysis
10.
Environ Res ; 208: 112780, 2022 05 15.
Article in English | MEDLINE | ID: mdl-35065930

ABSTRACT

Periodic starvation was a common strategy for the rapid start-up of aerobic granular sludge (AGS), and investigating the behavior of microbes that originated from inner or outer layer in response to feast/famine condition could provide more details for the development or stability of AGS. In this work, the microbes of the AGS were isolated by layers, the aggregation of microbes, the adhesion behavior of microbes, and viscoelasticity of the layer formed by microbes, at feast/famine conditions, were investigated for the in-depth understanding of the start-up and stability of AGS. The famine condition reduced the negative charge and deprotonated carboxyl groups of the surface thereby boosting the aggregation and adhesion of microbes. The feast condition was more beneficial for the stability of the layer as it caused a denser layer of microbes. The inner core microbes (IC) presented a higher aggregation rate than the outer layer microbes (OL) at feast/famine conditions. Also, the IC presented the highest aggregation rate, adhesion rate, and adhesion mass at famine conditions, which was most in favor of the start-up stage of the aerobic granulation. Since the denser layer was formed by IC, IC had better advantages over OL at the famine stage in the formation of a more stable layer. This study affirmed the role of microbes in the inner layer of the granule during the start-up phase and provided a theoretical basis for understanding the significance of the famine period for rapid granulation.


Subject(s)
Sewage , Waste Disposal, Fluid , Aerobiosis , Bioreactors , Viscosity
11.
Bioresour Technol ; 347: 126422, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34838963

ABSTRACT

The addition of biochars to promote the efficiency of anaerobic digestion (AD) has widely received concerns. However, the role of persistent free radicals (PFRs) and the electron transfer ability of biochar in AD has not yet been noticed. In this study, biochars were prepared from excess sludge under 400 °C (B400) or 600 °C (B600) and different ratios of sludge to biochar (5:1, 10:1, 20:1) were applied in the AD of sludge. The results verified that PFRs in biochar participated in the sterilization of microorganisms in sludge, resulting in the release of organic matters. Similar to electron mediators, biochars possessed electron exchangeability and the addition of biochars boosted the biogas production by maximum of 54.5%. The enhancing effect of B400 surpassed that of B600 as high temperature destroyed functional groups and reduced the defect degree of biochar. This study achieved in-situ resource utilization and provided references for the improvement of anaerobic digestion.


Subject(s)
Biofuels , Sewage , Anaerobiosis , Bioreactors , Charcoal , Electrons , Free Radicals , Methane
12.
J Environ Manage ; 299: 113602, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34454201

ABSTRACT

The pyrolysis of excess sludge derived from wastewater treatment plants to prepare biochar can achieve the mass-reduction and harmlessness of solid waste, but it is also necessary to further explore the application prospect of these biochars as a resource for wastewater treatment. In this study, Fe-modified biochar (BC-Fe) was prepared by pyrolysis of excess sludge modified by FeCl3 solution. The molecular structure, elemental valence state, and composition of biochars were comprehensively investigated. The results showed that, compared with the biochar prepared from sludge without modification (BC-blank), the O/C ratio of BC-Fe increased from 0.07 to 0.12, and the (N + O)/C ratio increased from 0.21 to 0.27, indicating increased polarity and weakened aromaticity. The ratio of integrated intensity of the D band and G band in the Raman spectrum increased from 1.34 to 2.40, showing the increased defect structure of the biochar obtained by Fe modification. In the reaction between BC-Fe and dicamba, the removal rate of dicamba reached 92.1% within 180 min, which was far higher than the 17.8% of BC-blank. It was confirmed the adsorption removal dominated and accounted for 70.6% of the dicamba removal by BC-Fe, and the adsorption capacity of biochar could be significantly enhanced by Fe-modification by 5.3 times. Moreover, the persistent free radicals (PFRs) on the surface of biochar was detected by an electron paramagnetic resonance analyzer, and the decline of PFRs signals after the reaction revealed that PFRs participated in the degradation process of dicamba. Through Q-TOF analysis, it could be concluded that dicamba was first converted to 3,6-dichlorosalicylic acid (DCSA) by PFRs reduction and then further transformed to 3,6-dichlorogentisic acid (DCGA). This study provided a reference for the understanding of the removal mechanism of dicamba by Fe-modified biochar and offered an application potential of biochar derived from Fe-containing sludge for the pollution control of dicamba pesticide pollutants.


Subject(s)
Sewage , Water Pollutants, Chemical , Adsorption , Charcoal , Dicamba , Water Pollutants, Chemical/analysis
13.
Environ Res ; 198: 111311, 2021 07.
Article in English | MEDLINE | ID: mdl-33989628

ABSTRACT

The start-up and stability of aerobic granular sludge (AGS) could be greatly influenced by pH variation. The inner core in the aerobic granules provided adhesion sites for microbes by extracellular polymeric substances (EPS) adhesion, the adhesion behavior of EPS and the properties of adhesion layer formed by EPS with pH changes might directly affect the start-up efficiency and stability of AGS. In this study, the adhesion behavior of EPS at an inorganic surface and the viscoelasticity of the EPS adhesion layer with pH variation was investigated by quartz crystal microbalance with dissipation monitoring, and the response of functional groups and intermolecular interactions to pH changes was explored. Based on the interaction energy calculation, it was found that the charge repulsion between substances dominated the interactions between EPS components and between EPS and the surface by regulating protonation and deprotonation of the functional groups of EPS with pH variation. A lower energy barrier between EPS and the surface at a lower pH value could facilitate the adhesion of EPS at the surface, which favored the rapid start-up of AGS. Moreover, the high ratio of both α-helix and intermolecular hydrogen bond at an acid condition could enhance the gel-strength of EPS, which provide AGS the resistance ability against external disturbance. This study revealed the mechanism of the interactions in EPS adhesion process with the variation of pH and provided useful information for a better understanding of the stability of the AGS.


Subject(s)
Extracellular Polymeric Substance Matrix , Waste Disposal, Fluid , Aerobiosis , Bioreactors , Hydrogen-Ion Concentration , Sewage , Viscosity
14.
J Environ Manage ; 284: 112113, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33571853

ABSTRACT

The improvement of the catalytic performance of sludge-based biochar plays an important role in the catalytic application of biochar. This work aimed to use transition metals and rare earth elements (Fe, Ce, La, Al, Ti) to modify sludge and prepare modified biochar with better catalytic performance through pyrolysis. Through the Fourier transform infrared spectrometer, Raman spectrometer, and X-ray photoelectron spectroscopy, the effects of different metal modifications on the surface morphology, molecular structure, element compositions, and valence of elements of biochar were comprehensively investigated. The results showed that metal elements were successfully modified onto the surface of biochar as metal oxides. Although the highest intensity of persistent free radicals was detected in blank-biochar by electron spin resonance, the intensities of hydroxyl radicals catalyzed by modified biochars in H2O2 system were higher than that catalyzed by blank-biochar, indicating that the catalytic performance of modified biochar was mainly related to the metal oxide loaded and the defect structure on the surface of metal-modified biochar. Furthermore, in the H2O2 system, the degradation efficiencies of tetracycline catalyzed by the biochars within 4 h were 51.7% (blank-biochar), 90.7% (Fe-biochar), 69.0% (Ce-biochar), 59.9% (La-biochar), 58.0% (Al-biochar), 58.0% (Ti-biochar), respectively, suggesting that Fe-biochar not only possessed the best catalytic performance but also shortened the reaction time. This research not only provided the possibility for recycling the waste activated sludge, but also proposed a modification method to improve the catalytic performance of biochar.


Subject(s)
Hydrogen Peroxide , Sewage , Adsorption , Catalysis , Charcoal
15.
Sci Total Environ ; 763: 142947, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33498111

ABSTRACT

Waste activated sludge (WAS) has attracted considerable attention as an excellent material for P recovery from sewage. This study took concentrated phosphorus removal sludge as objective, and aimed at providing an effective route to promote the transformation of polyphosphate in sludge pellets to dissolved phosphate. After acid pH adjustment, total dissolved phosphate at pH 3.0 was 37.3-fold higher than that at natural pH. The P distribution results illustrated that acid pH accelerated the degradation of short chain polyphosphate into orthophosphate. Furthermore, cell staining results confirmed that the polyphosphate was sourced from the leakage of intracellular matters. Low field NMR and rheology properties analysis were adopted to illustrate that acid pH treatment further improved WAS dewatering performances. Accompanied with the reduction of heavy metals in WAS pellets, the acid pH treatment was also beneficial for WAS subsequent treatment or final disposal. Lastly, Fe3+ addition was proposed as favorable P recovery method, and spherical nanometric materials of FePO4 crystal was obtained accordingly.


Subject(s)
Phosphorus , Sewage , Polyphosphates , Waste Disposal, Fluid
16.
Bioresour Technol ; 295: 122305, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31675520

ABSTRACT

A quinone-respiring strain capable of degrading multitudinous petroleum hydrocarbons was isolated by selective medium and identified as Bacillus sp. (named as C8). Maximum 76.7% of total petroleum hydrocarbons (TPH) were degraded by the biosurfactant-mediated C8 with the aid of nitrate and electron intermediate (anthraquinone-2,6-disulphonate, AQDS). The quantitative real-time PCR results of several intracellular key functional genes suggested that AQDS could participate in the transformation of intermediates and accelerate the electron transfer in the degradation of TPH and nitrate, thereby eliminating the accumulation of nitrite and increasing the degradation efficiency of TPH. A strengthening mechanism, which promoted electron transport in the anaerobic denitrification degradation of petroleum hydrocarbons by quinone-respiring strain with the aid of electron intermediate, was proposed. The influencing factors were evaluated by using response surface methodology, and the TPH removal was positively related to temperature but negatively to pH.


Subject(s)
Petroleum , Soil Pollutants , Anaerobiosis , Biodegradation, Environmental , Electrons , Hydrocarbons
17.
Huan Jing Ke Xue ; 40(7): 3216-3222, 2019 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-31854721

ABSTRACT

Mechanical, chemical, and biological methods are always used to pretreat sewage sludge. To determine which pretreatment can release more organic matter from sewage sludge, and therefore, make it more economical, mechanical pretreatment (ultrasonic treatment at 20 kHz), chemical pretreatment (pH 10), and biological pretreatment (anaerobic conditions at 70℃) were compared. Results showed that all three pretreatments increased the organic matter release of sewage sludge; the initial total soluble protein and carbohydrate concentration of which was only 418.9 mg·L-1 (cal. as COD) and the DNA content was 18.1 mg·L-1. However, the pH 10 and anaerobic (70℃) pretreatments resulted in a greater organic release than the ultrasonic (20 kHz) pretreatment, with total soluble protein and carbohydrate concentrations of 7516.0 mg·L-1 and 7892.5 mg·L-1, and DNA contents of 1343.3 mg·L-1 and 1766.1 mg·L-1, respectively. Flow cytometry was adopted to assess cell morphology. The cell mortality rates of sludge after pretreatment accounted for 61.6%, 59.9%, and 34.5% respectively, which was improved by 45.6% (at pH 10), 43.9% (under anaerobic conditions at 70℃), and 18.5% (with ultrasonic pretreatment at 20 kHz) compared with raw sewage sludge. At the same time, organic matter removal ratios of sludge after pretreatment were 19.1% (at pH 10), 13.8% (under anaerobic conditions at 70℃), and 7.6% (with ultrasonic pretreatment at 20 kHz). Moreover, the pretreatment of per liter sludge at pH 10 saved 28.5% and 124.1% more than ultrasonic pretreatment (20 kHz) and anaerobic (70℃) pretreatment. Taking both organic matter release and economic analysis into consideration, the chemical method of pretreatment (at pH 10) was identified as the best option.

18.
J Environ Manage ; 232: 197-206, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30472563

ABSTRACT

The process of anaerobic co-digestion is vital importance to resource recovery from organic solid wastes such as food waste and municipal sludge. However, its application is hindered by the limited understanding on the complex substrates-products transformation reactions and mechanisms therein. In this study, food waste (FW) and excess sludge (ES) from municipal wastewater treatment were mixed at various ratios (ES/FW 5:0, 4:1, 2:1, 1:1, 1:2, 1:4, w/w), and the co-digestion process was studied in a batch test. The consumption of substrates including soluble proteins and carbohydrates, the variation in the intermediates such as various volatile fatty acids, and the production of hydrogen and methane gases were monitored. The results suggested that 4:1 was likely the optimal ratio where substrates were consumed and biogas generated efficiently, whereas 1:2 and 1:4 caused severe inhibition. Fermentation of ES alone produced mainly acetic and propionic acid, while the addition of FW led to butyric acid type fermentation. Intermediates in the fermentation liquid were tentatively identified, and the levels of NADH quantified using 3D-excitation/emission fluorescence spectrometry. One class of the intermediates, tryptophan-like proteins were correlated to the butyric acid accumulation in ES/FW mixtures, and NADH level was proposed as an indicator of VFAs production activities.


Subject(s)
NAD , Sewage , Anaerobiosis , Bioreactors , Fatty Acids, Volatile , Food , Methane
19.
J Med Virol ; 86(6): 963-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24615954

ABSTRACT

Tonsillar and adenoidal hypertrophy are prevalent otolaryngologic disorders in children, but their pathogenesis is largely unknown. The presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) DNA in 146 tonsil and/or adenoid tissue specimens from 104 Chinese children with tonsillar and/or adenoidal hypertrophy were screened using flow-through hybridization gene-chip technology and real-time fluorescence-based quantitative PCR. Then, the relationships between the prevalence of the viruses and other clinical characteristics of tonsillar and/or adenoidal hypertrophy were analyzed. No patient had HPV DNA. EBV DNA was detected in 19/42 (45.2%) tonsil tissues and 72/104 (69.2%) adenoid tissue specimens (P < 0.05). EBV DNA was not related to the patients' age, gender, disease course, or nationality, but children positive for EBV were less likely to snore; 14/15 (93.3%) patients who did not snore and 59/89 (66.3%) patients who snored were EBV positive. EBV DNA, but not HPV DNA was detected in Chinese children with tonsillar and/or adenoidal hypertrophy. Adenoid tissues might more susceptible than tonsil tissues to EBV infection. In addition, EBV infection did not aggravate snoring in patients with tonsillar and/or adenoidal hypertrophy.


Subject(s)
Adenoids/pathology , Epstein-Barr Virus Infections/epidemiology , Herpesvirus 4, Human/isolation & purification , Hypertrophy/virology , Papillomaviridae/isolation & purification , Papillomavirus Infections/epidemiology , Adenoids/virology , Asian People , Child , Child, Preschool , China , DNA , Epstein-Barr Virus Infections/virology , Female , Herpesvirus 4, Human/genetics , Humans , Male , Nucleic Acid Hybridization , Oligonucleotide Array Sequence Analysis , Papillomaviridae/genetics , Papillomavirus Infections/virology , Prevalence , Real-Time Polymerase Chain Reaction
20.
Oncol Lett ; 7(3): 834-838, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24527091

ABSTRACT

Human papillomavirus (HPV) infection has been shown to be associated with human tumorigenesis. The aim of the present study was to demonstrate the association between HPV infection and parotid gland tumors. Paraffin-embedded tissue sections from 59 cases of parotid gland tumors and 20 normal oral mucosa were subjected to DNA extraction and flow-through hybridization and gene chip technology to detect infection of 37 HPV types. The HPV-positive rate was 57.6% in parotid gland tumor paraffin-embedded tissue specimens, whereas, the normal control group was negative for HPV. The HPV-positive rate was 59.6% in parotid gland benign tumor tissues and 42.9% in parotid malignant tissues. HPV infection in parotid gland tumors was dominated by the high-risk subtypes (80.7%), which mainly consisted of HPV 16, 18 and 52 (61.4%). In addition, parotid gland tumor tissues were found to be infected by multiple or single types of HPV, but were predominantly infected by mixed HPV types. In this study, we found that the occurrence of parotid gland tumor is correlated with HPV infection.

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