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1.
NMR Biomed ; 37(2): e5051, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37926525

RESUMO

The objective of the current study was to develop and evaluate a DEep learning-based rapid Spiral Image REconstruction (DESIRE) and deep learning (DL)-based segmentation approach to quantify the left ventricular ejection fraction (LVEF) for high-resolution spiral real-time cine imaging, including 2D balanced steady-state free precession imaging at 1.5 T and gradient echo (GRE) imaging at 1.5 and 3 T. A 3D U-Net-based image reconstruction network and 2D U-Net-based image segmentation network were proposed and evaluated. Low-rank plus sparse (L+S) served as the reference for the image reconstruction network and manual contouring of the left ventricle was the reference of the segmentation network. To assess the image reconstruction quality, structural similarity index, peak signal-to-noise ratio, normalized root-mean-square error, and blind grading by two experienced cardiologists (5: excellent; 1: poor) were performed. To assess the segmentation performance, quantification of the LVEF on GRE imaging at 3 T was compared with the quantification from manual contouring. Excellent performance was demonstrated by the proposed technique. In terms of image quality, there was no difference between L+S and the proposed DESIRE technique. For quantification analysis, the proposed DL method was not different to the manual segmentation method (p > 0.05) in terms of quantification of LVEF. The reconstruction time for DESIRE was ~32 s (including nonuniform fast Fourier transform [NUFFT]) per dynamic series (40 frames), while the reconstruction time of L+S with GPU acceleration was approximately 3 min. The DL segmentation takes less than 5 s. In conclusion, the proposed DL-based image reconstruction and quantification techniques enabled 1-min image reconstruction for the whole heart and quantification with automatic reconstruction and quantification of the left ventricle function for high-resolution spiral real-time cine imaging with excellent performance.


Assuntos
Aprendizado Profundo , Volume Sistólico , Imagem Cinética por Ressonância Magnética/métodos , Função Ventricular Esquerda , Imageamento Tridimensional/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética
2.
J Environ Manage ; 348: 119171, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832287

RESUMO

Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca2+), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation.


Assuntos
Substâncias Húmicas , Purificação da Água , Substâncias Húmicas/análise , Destilação/métodos , Microbolhas , Membranas Artificiais , Purificação da Água/métodos , Cátions
3.
J Fluoresc ; 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615895

RESUMO

Cisplatin is an important platinum drug in cancer chemotherapy in clinical practice. It is well established that the main target of cisplatin is nuclear DNA. However, recent studies have demonstrated that platinum drugs may act on some important functional proteins in the human body. E-cadherin is a newly discovered glycoprotein that has been regarded as an important sign of the occurrence and development of some tumors. This study examines the interactions between cisplatin and E-cadherin by fluorescence spectrometry and atomic force microscopy (AFM). The fluorescence spectrometry results indicated that cisplatin can efficiently quench the fluorescence of E-cadherin. The calculated binding constant Kb was 3.20 × 106 (25 ℃), 1.36 × 106(31 ℃), and 8.22 × 105 L mol-1 (37 ℃). These results reveal that the fluorescence quenching effect of cisplatin on E-cadherin is static quenching. The obtained thermodynamic parameters ΔH < 0, ΔS < 0, and ΔG < 0, indicate that the binding of cisplatin on E-cadherin is a spontaneous process dominated by hydrogen bonds and Van der Waals forces. The AFM results revealed that E-cadherins are interlaced with each other to form a spherical-chain structure. The addition of cisplatin can significantly disrupt the interlaced structure of the E-cadherin molecules.

4.
Front Oncol ; 13: 1160548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256172

RESUMO

Background: Hepatoblastoma has an unsatisfactory prognosis, and traditional chemotherapy has strong side effects. Dihydromyricetin is a flavonoid extracted from a woody vine of the genus Serpentine in the family Vitaceae, with effects such as preventing alcoholic liver and reducing the incidence of liver cancer. However, the effect of DHM on hepatoblastoma and its specific pathway are still unclear. Purpose: The purpose of this study was to investigate the effects of DHM on children's hepatoblastoma and its related mechanisms. Methods: CCK-8 assays were used to measure proliferation. Apoptosis and reactive oxygen species (ROS) were analyzed by flow cytometry. Apoptotic cells were observed using Hoechst 33342 staining and fluorescence microscopy. Protein expression levels in HuH-6 and HepG2 cells were determined by western blotting. Results: We found that DHM was able to inhibit the growth and increase cellular mortality in HuH-6 and HepG2 cells. Furthermore, DHM decreased the intracellular ROS level and increased the expression of SOD1. ROS scavenger NAC promoted apoptosis, while the use of SOD1 inhibitor LCS-1 weakened the ROS scavenging effect of DHM , and to some extent reduced the killing effect of DHM on hepatoblastoma cells. Conclusion: These results suggest that regulating SOD1/ROS pathway to induce apoptosis is one of the potential mechanisms of DHM as a tumor suppressor in hepatoblastoma. Therefore, DHM may be a novel candidate for inhibiting hepatoblastoma growth and deserves further study.

5.
Antibiotics (Basel) ; 12(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36830111

RESUMO

The chestnut shell is usually discarded as agricultural waste and the random deposition of it can cause environmental problems. In this study, monodisperse crystalline Ag nanoparticles (AgNPs) were synthesized by a hydrothermal approach, in which the chestnut shell extract served as both reducing agent and stabilizer. The synthesized Ag nanoparticles were characterized by ultraviolet-visible (UV) spectrophotometry, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) measurements. The TEM, XRD and XPS results revealed that the synthesized product was spherical Ag nanoparticles with a face-centered cubic crystal structure. The antimicrobial activity test indicated that the Ag nanoparticles modified by the chestnut shell extract had an obvious inhibitory effect on Escherichia coli, Staphylococcus aureus and Candida albicans. The measured MIC and MBC of functionalized chestnut-shell-extract AgNPs against E. coli, S. aureus and C. albicans is relatively low, which indicated that the present functionalized chestnut-shell-extract AgNPs are an efficient antimicrobial agent.

6.
Sci Total Environ ; 857(Pt 1): 159384, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36240921

RESUMO

Phytoremediation assisted by endophytic bacteria is promising to efficiently remediate cadmium (Cd) contaminated soil. Bacillus cereus BL4, isolated from Miscanthus floridulus growing around a pyrite mine, exhibited high Cd tolerance and plant growth-promoting traits and could improve Cd bioavailability in soil. As a result of the pot experiment, after inoculation with strain BL4, the fresh weight, height, and Cd accumulation of Miscanthus floridulus shoots increased by 19.08-32.26 %, 6.02-16.60 %, and 23.67 %-24.88 %, respectively, and roots increased by 49.38-56.41 %, 22.87-33.93 %, and 28.51 %-42.37 %, respectively. Under Cd stress, the chlorophyll content, photosynthetic rate, and root activity of Miscanthus floridulus increased, while the membrane permeability and malonaldehyde (MDA) content significantly decreased after the inoculation of BL4, which indicated the alleviation of the cytotoxicity of Cd. Accordingly, the glutathione (GSH) content increased, and the activities of antioxidant enzymes presented downward trends after BL4 inoculation. Cd bioavailability in soil increased after BL4 inoculation, accompanied by increases in the activities of soil enzymes (invertase, urease, alkaline phosphatase, dehydrogenase, FDA hydrolase, and catalase) as well as the richness and diversity of soil bacteria. Our findings revealed that strain BL4 might strengthen the phytoremediation of Cd by Miscanthus floridulus through its effects on plant physio-biochemistry and soil microecology, which provided a basis for the relative application to Cd-contaminated soil.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Solo/química , Bacillus cereus , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Biodegradação Ambiental , Poaceae , Raízes de Plantas/química
7.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4462-4468, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-36046876

RESUMO

An ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method was established for the determination of active components of Sarcandrae Herba, and applied to the pharmacokinetics study of multiple dosage forms. After SD rats were administered by gavage with three dosage forms [Sarcandrae Herba extract, commercial Sarcandrae Herba Guttate Pills, and polydopamine guttate pills loaded with active components of Sarcandrae Herba(PDA-Sg Guttate Pills)], blood samples were collected from the inner canthus at different time points. After protein precipitation, plasma samples were separated on ACQUITY UPLC C_(18) column(2.1 mm×100 mm, 1.7 µm). The mobile phase consisted of water containing 0.2% formic acid and acetonitrile in gradient elution. The negative ions were measured simultaneously in the multi-reaction monitoring(MRM) mode. The pharmacokinetic parameters were calculated and fitted by DAS 2.0. All four components could be detected in the plasma of rats in each group at each time point except the neochlorogenic acid and cryptochlorogenic acid in the Sarcandrae Herba extract group. The guttate pills group showed a significant increase in drug content at each time point. The exposure of the main components of Sarcandrae Herba in blood was effectively increased by PDA-drug loading effect in PDA-Sg Guttate Pills(The AUC_(0-24 h) of neochlorogenic acid, cryptochlorogenic acid, isaziridin and rosmarinic acid reached 2.45, 32.90, 1.54, 4.81 times that of the commercial guttate pills). This study proves the measurability of the above-mentioned multi-component in vitro-in vivo delivery process. The pharmacokinetic study has shown that PDA-Sg Guttate Pills can effectively delay the elimination time and improve the bioavailability of the four components, which can provide theoretical data for the production of the drug.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Indóis , Polímeros , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
8.
Int J Pharm ; 611: 121330, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34864120

RESUMO

The oral bioavailability of many phenolic acid drugs is severely limited due to the high hydrophilicity and extensive first-pass effect induced by catechol-O-methyltransferase (COMT) metabolism. The present study investigated the inhibitory activity of the pharmaceutical excipients of extra virgin olive oil (EVOO) against COMT and evaluated the potential of a self-microemulsion loaded with a phospholipid complex containing EVOO for oral absorption enhancement of salvianolic acid B (SAB), a model phenolic acid. In vitro COMT assay showed that EVOO could effectively inhibit enzyme activity in the rat liver cytosol. Next, the SAB phospholipid complex/self-microemulsion containing EVOO (named SP-SME1) was prepared and characterized (particle size, 243.60 ± 6.96 nm and zeta potential, -23.67 ± -1.36 mV). The phospholipid complex/self-microemulsion containing ethyl oleate (EO) (named SP-SME2) was taken as the control group. Compared with free SAB, the apparent permeability coefficient (Papp value) of the two SP-SMEs significantly increased (12.0-fold and 10.90-fold). Pharmacokinetic study demonstrated that the AUC0-∞ value of SAB for the SP-SME1 group significantly increased by 4.72 and 2.82 times compared to those for free SAB (p < 0.001) and SP-SME2 (p < 0.01), respectively. Moreover, the AUC0-∞ value of monomethyl-SAB (metabolite of SAB, MMS) for the SP-SME1 group decreased by 0.83 times compared to that for SP-SME2. In conclusion, the EVOO-based phospholipid complex/self-microemulsion greatly enhanced the oral absorption of SAB, which was mainly attributed to the inhibition of COMT activity induced by EVOO.


Assuntos
Benzofuranos/metabolismo , Catecol O-Metiltransferase , Azeite de Oliva/química , Fosfolipídeos/química , Animais , Catecol O-Metiltransferase/metabolismo , Ratos
9.
Sci Total Environ ; 802: 149899, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464792

RESUMO

A mass of tailings left by mineral exploitation have caused serious environmental pollution. Although many studies have shown that soil microorganisms have the potential to remediate environmental pollution, the interaction mechanism between microorganisms and the surrounding environment of tailings is still unclear. In this study, 15 samples around pyrite mine tailing were collected to explore the ecological effects of environmental factors on bacterial community. The results showed that most of the samples were acidic and contaminated by multiple metals. Cadmium (Cd), copper (Cu), nickel (Ni) migrated and accumulated to into downstream farmlands while chromium (Cr) was the opposite. Proteobacteria, Chloroflex and Actinobacteria were the dominant phyla. Soil pH, total phosphorus (TP), total nitrogen (TN), available potassium (AK), available phosphorus (AP), the bacteria abundance and diversity all gradually increased with the increase of the distance from the tailing. Invertase, acid phosphatase, total organic carbon (TOC), pH, TP and Cr were the main influencing factors to cause the variation of bacterial community. This work could help us to further understand the changes in soil microbial communities around pollution sources.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Poluição Ambiental , Metais Pesados/análise , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
10.
Environ Sci Pollut Res Int ; 29(1): 584-593, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34341927

RESUMO

Characteristics and resistant mechanisms of macro-fungus endophytic bacteria to cadmium (Cd) have not been well defined. Strains L1 and L3 with Cd-resistant capacity were isolated from the fruiting body of Coprinus comatus, which were identified as Bacillus sp. Under the stress of Cd, the morphologies of both L1 and L3 changed to reduce the threat of Cd. The results of Fourier Transform Infrared Spectrometry indicated that functional groups such as -OH, -COOH, and -NH2 participated in the Cd adsorption process. The contents of Cd adsorbed on the cell wall of L1 were 83.46-174.51% higher than that of L3. On the contrary, the contents of Cd accumulated in L1 cytoplasm were 38.77-74.77% lower than that of L3. As the level of Cd increased from 10 to 30 mg/L, the percentages of Cd distributed on the cell walls of L1 and L3 increased by 42.43% and 26.78%, respectively. The results also revealed that the contents of Cd absorbed by the sterilized strains L1 and L3 were 47.67-64.94% and 8.65-78.63% higher than that of living ones, respectively. In addition, the proline production of L1 was 23.75-109.68% higher than that of L3, while the malondialdehyde (MDA) production of L1 was 0.96-15.60% lower than that of L3. Thus, through the comparison of endophytic bacterial physiological responses, the possible characteristics and resistant mechanisms of macro-fungus endophytic bacteria under Cd stress were firstly reported.


Assuntos
Coprinus , Poluentes do Solo , Bactérias , Cádmio/análise , Raízes de Plantas/química , Poluentes do Solo/análise
11.
J Nanobiotechnology ; 19(1): 409, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876139

RESUMO

BACKGROUND: Attenuating inflammatory response and relieving pain are two therapeutic therapeutical goals for rheumatoid arthritis (RA). Anti-inflammatory and analgesic drugs are often associated with many adverse effects due to nonspecific distribution. New drug delivery systems with practical targeting ability and other complementary strategies urgently need to be explored. To achieve this goal, an acupoint drug delivery system that can target deliver anti-inflammatory drugs and simulate acupuncture in relieving pain was constructed, which can co-deliver triptolide (TP) and 2-chloro-N (6)-cyclopentyl adenosine (CCPA). RESULTS: We have successfully demonstrated that acupoint nanocomposite hydrogel composed of TP-Human serum album nanoparticles (TP@HSA NPs) and CCPA could effectively treat RA. The result shows that CCPA-Gel can enhance analgesic effects specifically at the acupoint, while the mechanical and thermal pain threshold was 4.9 and 1.6 times compared with non-acupoint, respectively, and the nanocomposite gel further enhanced. Otherwise, the combination of acupoint and nanocomposite hydrogel exerted synergetic improvement of inflammation, bone erosion, and reduction of systemic toxicity. Furthermore, it could regulate inflammatory factors and restore the balance of Th17/Treg cells, which provided a novel and effective treatment strategy for RA. Interestingly, acupoint administration could improve the accumulation of the designed nanomedicine in arthritic paws (13.5% higher than those in non-acupoint at 48 h), which may explain the better therapeutic efficiency and low toxicity. CONCLUSION: This novel therapeutic approach-acupoint nanocomposite hydrogel, builds a bridge between acupuncture and drugs which sheds light on the combination of traditional and modern medicine.


Assuntos
Pontos de Acupuntura , Anti-Inflamatórios , Artrite Reumatoide/metabolismo , Diterpenos , Nanogéis , Fenantrenos , Terapia por Acupuntura , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Comportamento Animal/efeitos dos fármacos , Preparações de Ação Retardada , Diterpenos/química , Diterpenos/farmacocinética , Diterpenos/farmacologia , Sistemas de Liberação de Medicamentos , Compostos de Epóxi/química , Compostos de Epóxi/farmacocinética , Compostos de Epóxi/farmacologia , Humanos , Masculino , Nanomedicina , Fenantrenos/química , Fenantrenos/farmacocinética , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley
12.
Research (Wash D C) ; 2021: 9802795, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34738087

RESUMO

We report a novel Mn-Co-Ni-O (MCN) nanocomposite in which the p-type semiconductivity of Mn-Co-Ni-O can be manipulated by addition of graphene. With an increase of graphene content, the semiconductivity of the nanocomposite can be tuned from p-type through electrically neutral to n-type. The very low effective mass of electrons in graphene facilitates electron tunneling into the MCN, neutralizing holes in the MCN nanoparticles. XPS analysis shows that the multivalent manganese ions in the MCN nanoparticles are chemically reduced by the graphene electrons to lower-valent states. Unlike traditional semiconductor devices, electrons are excited from the filled graphite band into the empty band at the Dirac points from where they move freely in the graphene and tunnel into the MCN. The new composite film demonstrates inherent flexibility, high mobility, short carrier lifetime, and high carrier concentration. This work is useful not only in manufacturing flexible transistors, FETs, and thermosensitive and thermoelectric devices with unique properties but also in providing a new method for future development of 2D-based semiconductors.

13.
Biomed Pharmacother ; 142: 111927, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34339914

RESUMO

Recent studies demonstrated that dihydromyricetin (DHM) has prominent therapeutic effects on liver injury and liver cancer. By summarizing the current preclinical in vitro and in vivo studies, the present review examines the preventive and therapeutic effects of DHM on liver disorders as well as its potential mechanisms. Briefly, in both chemical- and alcohol-induced liver injury models, DHM ameliorates hepatocyte necrosis and steatosis while promoting liver regeneration. In addition, DHM can alleviate nonalcoholic fatty liver disease (NAFLD) via regulating lipid/glucose metabolism, probably due to its anti-inflammatory or sirtuins-dependent mechanisms. Furthermore, DHM treatment inhibits cell proliferation, induces apoptosis and autophagy and regulates redox balance in liver cancer cells, thus exhibiting remarkable anti-cancer effects. The pharmacological mechanisms of DHM may be associated with its anti-inflammatory, anti-oxidative and apoptosis-regulatory benefits. With the accumulating interests in utilizing natural products to target common diseases, our work aims to improve the understanding of DHM acting as a novel drug candidate for liver diseases and to accelerate its translation from bench to bedside.


Assuntos
Flavonóis/farmacologia , Flavonóis/uso terapêutico , Hepatopatias/prevenção & controle , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/prevenção & controle , Flavonóis/farmacocinética , Humanos , Hepatopatias/metabolismo , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/prevenção & controle , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/prevenção & controle , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/prevenção & controle , Regeneração Hepática/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Substâncias Protetoras/farmacocinética
14.
Membranes (Basel) ; 11(6)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072411

RESUMO

Soy sauce is a common condiment that has a unique flavor, one that is derived from its rich amino acids and salts. It is known that excessive intake of high-sodium food will affect human health, causing a series of diseases such as hypertension and kidney disease. Therefore, removing sodium from the soy sauce and retaining the amino acids is desirable. In this study, electrodialysis (ED) was employed for the desalination of soy sauce using commercial ion exchange membranes (IEMs). The influence of the current density and initial pH on the desalination degree of the soy sauce was explored. Results showed that the optimal desalination condition for ED was reached at a current density of 5 mA/cm2 and pH of 5, with the desalination degree of 64% and the amino acid loss rate of 29.8%. Moreover, it was found that the loss rate of amino acids was related to the initial concentration and molecular structure. In addition, the amino acid adsorption by IEMs was explored. Results implied that the molecular weight and structure affect amino acid adsorption. This study illustrated that the ED process can successfully reduce the salt content of the soy sauce and retain most of the amino acids without compromising the original flavor.

15.
Ecotoxicol Environ Saf ; 220: 112368, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082243

RESUMO

A field investigation on the content of heavy metals in soils and dominant plants was conducted in three sites (A<0.5 km, B<1.0 km, C<1.5 km) with different distances of mine tailings. The spatial distribution of heavy metals and the accumulation in plants were compared, and the candidate species for ecosystem restoration were selected. The results indicated that the soil was polluted by chromium (Cr), Cadmium (Cd), copper (Cu), nickel (Ni) in varying degrees, which is 2.07, 2.60, 1.79, and 4.49 times higher than the Class-Ⅱ standard in China. The concentrate of Ni, Cd, and Zinc (Zn) increased, while Cr, Lead (Pb), and Cu decreased with the distance from the mine tailings. 73 species (34 families) were found and mainly herbaceous plants. The concentrate of Cd, Cu, Cr, and Ni in 29 dominant plants were measured and 66.67%, 21.43%, 100%, 47.62% plants exceeded the normal concentration range. Based on the comparative analysis of heavy metal content, bioconcentration factor, and translocation factor in plants, Polygonum capitatum has good phytoextraction ability, Boehmeria nivea, Chrysanthemum indicum, Miscanthus floridulus, Conyza canadensis, Rubus setchuenensis, Senecio scandens, and Arthraxon hispidus showed remarkable phytostabilization abilities of Cr, Cd, Ni, and Cu, which can be used as potential phytoremediation candidate.


Assuntos
Metais Pesados/metabolismo , Mineração , Plantas/metabolismo , Poluentes do Solo/metabolismo , Bioacumulação , Biodegradação Ambiental , China , Metais Pesados/análise , Plantas/classificação , Solo/química , Poluentes do Solo/análise
16.
Chemosphere ; 274: 129661, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33979921

RESUMO

Biomineralization to immobilize the toxic metal has great potential for the bioremediation of multiple heavy metal contamination. In this study, the efficiency of Microbially Carbonate Induced Precipitation (MICP) for several common heavy metals (Cu, Zn, Ni, Cd) in mining areas as well as their precipitation patterns were researched. After urease activity and precipitation ability comparison, Sporosarcina kp-4 and kp-22 were selected for subsequent studies. The removal of Cd was mainly based on the formation of cadmium carbonate induced by bacteria activity, while the removal of Cu was depended on the pH increase generated by the same process. Precipitation contributed to Zn and Ni removal was more complex, which was also based on the MICP process. Removal rates of Cu, Zn, Ni, and Cd (the concentration of all metals was 160 mg/L) reached 75.10%, 98.03%, 59.46% and 96.18%, respectively, within 2 h. For the immobilization of Cu, Zn, Ni and Cd at 160 mg/L, the optimal dosages of bacterial cultured solution were about 0.25 mL, 0.8 mL, 0.5 mL and 0.8 mL, respectively. Minimum inhibitory concentrations (MIC) revealed the toxicity of these heavy metals for MICP bacteria was arrange as: Cd > Zn > Ni > Cu. Our study confirmed that urease-producing bacteria could coprecipitate multiple heavy metals even without the ability tolerate them, and the MICP process was an effective biological approach that was worth investigating further to immobilize multiple heavy metals in ecological restoration.


Assuntos
Metais Pesados , Bactérias , Biodegradação Ambiental , Carbonato de Cálcio , Carbonatos , Urease
17.
J Hazard Mater ; 416: 125814, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33866290

RESUMO

Pleurotus has great potential for heavy metal mycoremediation. Using comparative transcriptome analysis, the response of Pleurotus ostreatus and Pleurotus cornucopiae under Cd contamination was evaluated. P. ostreatus and P. cornucopia accumulated 0.34 and 0.46 mg/g Cd in mycelium, respectively. Cd removal elevated with its concentration elevation, which reached 56.47% and 54.60% for P. ostreatus and P. cornucopia with Cd at 20 mg/L. Low-level Cd (≤ 1 mg/L) had no significant influence on either fungus, while varied response was observed under high-level Cd. 705 differentially expressed genes (DEGs) were identified in P. cornucopia at Cd1 and Cd20, whereas 12,551 DEGs in P. ostreatus. Differentially regulated functional categories and pathways were also identified. ATP-binding cassette transporters were involved in Cd transport in P. cornucopia, whereas the endocytosis and phagosome pathways were more enhanced in P. ostreatus. 26 enzymes including peroxisomal enzymes catalase and superoxide dismutase were upregulated in P. ostreatus, whereas only cytosolic catalase was overexpressed in P. cornucopia, suggesting their different Cd detoxification pathways. Also, the mitogen-activated protein kinase signaling pathway involved in Cd resistance in both species instead of glutathione metabolism, although more active in P. ostreatus. These findings provided new insight into the molecular mechanism of mycoremediation and accumulator screening.


Assuntos
Pleurotus , Cádmio/toxicidade , Catalase , Perfilação da Expressão Gênica , Pleurotus/genética
18.
J Hazard Mater ; 412: 125156, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33556857

RESUMO

Microbially induced phosphate precipitation (MIPP) is an advanced bioremediation technology to immobilize heavy metals. An indigenous bacterium QY14 with the function of mineralization isolated from Cd contaminated farmland soil was identified as Burkholderia ambifaria. The minimum inhibitory concentration value for QY14 was 550 mg/L for soluble Cd concentration. This study found that the addition of 10 mM Ca2+ during MIPP process could significantly increase the removal ratio of Cd, and the maximum removal ratio of Cd with 10 mM Ca2+ and without Ca2+ in solution was 99.97% and 76.14%, respectively. The increase of acid phosphatase activity and the formation of precipitate containing calcium caused by 10 mM Ca2+ addition contributed the increase of Cd removal efficiency. The results of SEM-EDS, FTIR and XRD showed that Cd was removed by forming Cd containing hydroxyapatite (Cd-HAP). In addition, the dissolution experiment showed the Cd release ratio of Cd-HAP (0.01‰ at initial pH 3.0 of solution) was lower than Cd-absorbed HAP, indicating that Cd was more likely removed by the formation of Ca10-xCdx(PO4)6(OH)2 solid solution. Our findings revealed MIPP-based bioremediation supplied with 10 mM Ca2+ could increase the Cd removal and could potentially be applied for Cd remediation.


Assuntos
Burkholderia , Poluentes do Solo , Cádmio , Solo , Poluentes do Solo/análise
19.
Ecotoxicol Environ Saf ; 211: 111929, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33472107

RESUMO

Large amounts of cadmium (Cd) have been discharged into soil with the rapid development of industry. In this study, we revealed the impacts of Coprinus comatus (C. comatus) and Pleurotus cornucopiae (P. cornucopiae) on soil and the tolerance responses of macrofungi in the presence of Cd by the analysis of soil biochemical properties and macrofungi growth indexes. Results showed that with the cultivation of C. comatus and P. cornucopiae, the HOAc-extractable Cd in soil individually reduced by 9.53% and 11.35%, the activities of soil urease, acid phosphatase, dehydrogenase, and Fluorescein diacetate (FDA) hydrolysis increased by 18.11-101.45%, 8.39-18.24%, 9.37-55.50% and 28.94-41.92%, respectively. Meanwhile, different soil bacterial communities were observed with various macrofungi cultivations. Also, Cd accumulation significantly enhanced the macrofungi antioxidant enzyme activities, which increased by 24.10-45.43%, 30.11-61.53% and 7.03-26.81% for catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities in the macrofungi, respectively. Moreover, the enhanced macrofungi endophytic bacterial diversities with Cd existence was firstly observed in the present experiment. These findings revealed the possible Cd resistance mechanisms in macrofungi, suggesting C. comatus and P. cornucopiae were promising ameliorators for Cd contaminated soil.


Assuntos
Adaptação Fisiológica , Biodegradação Ambiental , Cádmio/toxicidade , Coprinus/fisiologia , Pleurotus/fisiologia , Poluentes do Solo/toxicidade , Antioxidantes/análise , Bactérias , Cádmio/análise , Catalase , Solo/química , Poluentes do Solo/análise
20.
Sci Rep ; 10(1): 18421, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116186

RESUMO

The efficient biological treatment of saline wastewater has been limited by the low activities of microorganisms under saline conditions. High salinity poses unbalance osmotic stress across the cell wall and even leads to cell plasmolysis. In this work, we aim to isolate salt-tolerant bacterial strains from activated sludge, and apply them for degrading chemical oxygen demand (COD) of saline organic wastewater. Two salt-tolerant strains were screened and isolated from activated sludge, which was domesticated with salty water for over 300 days. The two strains were identified as Bacillus cereus (strain A) and Bacillus anthracis (strain B) through 16S rRNA sequencing. The degradation characteristics of strain A were explored. The results showed the relative membrane permeability of strain A remained stable under high salt stress, which glycine and proline play an important role to maintain cell osmotic. The protein and soluble sugar amounts of strain were increased by higher salt concentrations. In simulating saline wastewater, the optimum culture temperature, pH, salinity, influent COD concentration and inoculation amount of strain A were 35 °C, 9, 4%, 8000 mg L-1, 6%, respectively. Optimal conditions could provide guidance for the treatment of practical saline wastewater. The linear regression model of each impact factor built based on the result PB experiment revealed that cross-linking time has the most significant influence on COD removal for salt-tolerant strains. It will provide theoretical basis for biological treatment of saline organic wastewater.


Assuntos
Bacillus anthracis/isolamento & purificação , Bacillus cereus/isolamento & purificação , Tolerância ao Sal , Águas Residuárias/microbiologia , Bacillus anthracis/fisiologia , Bacillus cereus/fisiologia , Análise da Demanda Biológica de Oxigênio , Permeabilidade da Membrana Celular , Salinidade
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