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1.
Food Chem ; 338: 127828, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822904

RESUMO

The fatty acid content of flour is an important indicator for determining the deterioration of flour. We propose a novel rapid measurement method for fatty acid content during flour storage based on a self-designed color-sensitive gas sensor array. First, a color-sensitive gas sensor array was prepared to capture the odor changes during flour storage. The sensor features were then optimized using genetic algorithm (GA), ant colony optimization (ACO) and particle swarm optimization (PSO). Finally, back propagation neural network (BPNN) models were established to measure the fatty acid content during flour storage. Experimental results showed that the optimization effects of the three algorithms improved in the following order: GA < ACO < PSO, for the sensor features optimization. In the validation set, the determination coefficient of the best PSO-BPNN model was 0.9837. The overall results demonstrate that the models established on the optimized features can realize rapid measurements of fatty acid content during flour storage.

2.
J Hazard Mater ; 401: 123724, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33113726

RESUMO

Organophosphates (OPs) are highly toxic compounds, with widespread application in agricultural and chemical industries, whose introduction into the environment poses serious hazards to humans and ecological systems. To assess and ultimately mitigate these hazards, this study predicted the acute toxicity of OPs according to their chemical structure and administration route. The acute toxicity data of 161 OPs in two species via six different administration routes were manually collected and used to develop a series of quantitative structure-toxicity relationship (QSTR) models with robust and practical predictive abilities. The random forest algorithm was used to develop the models, employing both quantum chemical and two-dimensional descriptors according to OECD guidelines. Correlation results and feature similarities indicated that whereas acute toxicity data from rats and mice via the same administration route were combinable for modeling, data from different routes were not. Six QSTR models for each route in a single species and two QSTR models for a single route in the two species were constructed, achieving practical predictive performance. Despite significant variances in their datasets, the prediction models could predict the acute toxicity of novel or unknown OPs, realize rapid assessment, and provide guidance for regulatory decisions to reduce the hazards of OPs.

3.
Eur Spine J ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219882

RESUMO

PURPOSE: Cervical dumbbell tumor is usually removed via a posterior approach and may require the spinal fixation sometimes. However, the present surgical methods involved either more trauma or a higher risk of instability of the cervical spine. A new technique of unilateral exposure and stability reconstruction with pedicle and lamina screws fixation for posterior cervical dumbbell tumorectomy was described and compared with conventional techniques. METHODS: Posterior unilateral exposure, hemi-laminectomy and facetectomy were performed in one patient with the cervical dumbbell tumor between C3 and C4. The stability was reconstructed by the unilateral pedicle and lamina screws fixation (UPLS), and a strip of shaped allograft bone was also implanted between the superior and inferior lateral mass. Biomechanical stability test of this new technique was investigated using seven fresh-frozen human cervical spine specimens (C4-C7) and compared with unilateral pedicle screw (UPS) and bilateral pedicle screw fixation (BPS) techniques. A continuous pure moment of ± 2.0 Nm was applied to the specimen in flexion, extension, lateral bending and axial rotation. RESULTS: The cervical dumbbell tumor was removed completely, and bone fusion with continuous bone trabecula was maintained in the patient on the final follow-up examination at 18 months postoperatively. Biomechanical stability tests revealed that the range of motion of the UPLS fixation plus graft bone implant was the same as the BPS fixation in flexion (1.8°vs. 1.5°, p = 0.58) and extension (2.3°vs. 2.2°, p = 0.73), but significantly bigger in lateral bending (3.9° vs. 1.0°, p < 0.001) and axial rotation (6.8° vs. 3.8°, p = 0.002), which were significantly smaller than the UPS fixation in all directions (all p < 0.001). CONCLUSIONS: For the treatment of cervical dumbbell tumor, posterior unilateral exposure and stability reconstruction with pedicle and lamina screws fixation following hemi-laminectomy and facetectomy appear to be a more stable and lesser trauma technique. LEVEL OF EVIDENCE: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

4.
J Sci Food Agric ; 2020 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-33222172

RESUMO

BACKGROUND: The acid value is one of the significant indicators for evaluating the quality of edible oil during storage. Herein, this study employs a portable near-infrared spectroscopy (NIRS) system to determine the acid value during edible oil storage. Four MPA-based variable selection methods, namely, competitive adaptive reweighted sampling (CARS), variable iterative space shrinkage approach (VISSA), iteratively variable subset optimization (IVSO) and bootstrapping soft shrinkage (BOSS), were introduced to optimize the preprocessed NIR spectra. Then, support vector machine (SVM) models based on characteristic spectra obtained by different selection methods were established to achieve quantitative detection of the acid value during edible oil storage. RESULTS: The results obtained revealed that compared to the full-spectrum SVM model, the SVM models established by the characteristic wavelengths optimized by the variable selection methods based on the MPA strategy exhibit a significant improvement in complexity and generalization performance. Furthermore, compared with the CARS, VISSA and IVSO methods, the BOSS method obtained the least number of characteristic wavelength variables, and the SVM model established based on the optimized features of this method exhibited the best prediction performance, with RMSEP = 0.11 mg g-1 , RP 2 =0.92 and RPD=2.82, respectively. CONCLUSION: The overall results indicate that the variable selection methods based on the MPA strategy can select more targeted characteristic variables, which has good application prospects in NIR spectra feature optimization. This article is protected by copyright. All rights reserved.

5.
J Agric Food Chem ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33205963

RESUMO

Animal husbandry is the second largest source of steroid estrogen (SE) pollutants in the environment, and it is significant to investigate the occurrence and fate of SEs discharged from concentrated animal feeding operations. In this research, with a Chinese typical concentrated dairy farm as the object, the concentrations of SEs (E1, 17α-E2, 17ß-E2, E3, and E1-S3) in slurry, lagoon water, and slurry-irrigated soil samples in summer, autumn, and winter were determined. The total concentrations of SEs (mainly E1, 17α-E2, and 17ß-E2) in slurry were very high in the range of 263.1-2475.08 ng·L-1. In the lagoon water, the removal efficiencies of the aerobic tank could reach up to 89.53%, with significant fluctuation in different seasons. In the slurry-irrigated soil, the maximum concentrations of SEs in the topsoil and subsoil were 21.54 ng·g-1 to 6.82 g·g-1, respectively. Most of the SEs tended to transport downward and accumulate in the soil accompanied with the complex mutual conversion. Correlations and hierarchical clustering analysis showed a variety of intertransformation among SEs, and the concentrations of SEs were correlated with various physicochemical indexes, such as TN and NO3--N of the slurry, chemical oxygen demand of the lagoon water, and the heavy metals of soil. In addition, 17ß-estradiol equivalency assessment and risk quotients indicated that the slurry irrigation and discharge of the lagoon water would cause potential estrogenic risks to the environment. Consequently, reasonable slurry irrigation and lagoon water discharge are essential to efficiently control SE pollution in the environment.

6.
BMC Bioinformatics ; 21(1): 518, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176676

RESUMO

BACKGROUND: DNBSEQ™ platforms are new massively parallel sequencing (MPS) platforms that use DNA nanoball technology. Use of data generated from DNBSEQ™ platforms to detect single nucleotide variants (SNVs) and small insertions and deletions (indels) has proven to be quite effective, while the feasibility of copy number variants (CNVs) detection is unclear. RESULTS: Here, we first benchmarked different CNV detection tools based on Illumina whole-genome sequencing (WGS) data of NA12878 and then assessed these tools in CNV detection based on DNBSEQ™ sequencing data from the same sample. When the same tool was used, the CNVs detected based on DNBSEQ™ and Illumina data were similar in quantity, length and distribution, while great differences existed within results from different tools and even based on data from a single platform. We further estimated the CNV detection power based on available CNV benchmarks of NA12878 and found similar precision and sensitivity between the DNBSEQ™ and Illumina platforms. We also found higher precision of CNVs shorter than 1 kbp based on DNBSEQ™ platforms than those based on Illumina platforms by using Pindel, DELLY and LUMPY. We carefully compared these two available benchmarks and found a large proportion of specific CNVs between them. Thus, we constructed a more complete CNV benchmark of NA12878 containing 3512 CNV regions. CONCLUSIONS: We assessed and benchmarked CNV detections based on WGS with DNBSEQ™ platforms and provide guidelines for future studies.

7.
Drug Des Devel Ther ; 14: 4815-4824, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204067

RESUMO

Purpose: The purpose of the present study was to investigate the effects of vonoprazan on the pharmacokinetics of venlafaxine in vitro and in vivo. Methods: The mechanism underlying the inhibitory effect of vonoprazan on venlafaxine was investigated using rat liver microsomes. In vitro, the inhibition was evaluated by determining the production of O-desmethylvenlafaxine. Eighteen male Sprague-Dawley rats were randomly divided into three groups: control group, vonoprazan (5 mg/kg) group, and vonoprazan (20 mg/kg) group. A single dose of 20 mg/kg venlafaxine was administrated to rats orally without or with vonoprazan. Plasma was prepared from blood samples collected via the tail vein at different time points and concentrations of venlafaxine and its metabolite, O-desmethylvenlafaxine, were determined by ultra-performance liquid chromatography-tandem mass spectrometry. Results: We observed that vonoprazan could significantly decrease the amount of O-desmethylvenlafaxine (IC50 = 5.544 µM). Vonoprazan inhibited the metabolism of venlafaxine by a mixed inhibition, combining competitive and non-competitive inhibitory mechanisms. Compared with that in the control group (without vonoprazan), the pharmacokinetic parameters of venlafaxine and its metabolite, O-desmethylvenlafaxine, were significantly increased in both 5 and 20 mg/kg vonoprazan groups, with an increase in MRO-desmethylvenlafaxine. Conclusion: Vonoprazan significantly alters the pharmacokinetics of venlafaxine in vitro and in vivo. Further investigations should be conducted to check these effects in humans. Therapeutic drug monitoring of venlafaxine in individuals undergoing venlafaxine maintenance therapy is recommended when vonoprazan is used concomitantly.

8.
Biosens Bioelectron ; 173: 112786, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33190050

RESUMO

A novel hydrogel loaded with adenosine 5'-monophosphate capped Au nanoclusters (AuAMP NCs) is fabricated in a gentle route by double-triggering of Zn2+. This built-in fluorescent hydrogel material not only has good optical properties of Au NCs, but also possesses excellent mechanical structure of hydrogel materials. Free phosphate ions may trigger the devastation of the "egg-box" structure of the as-prepared ZnSA-AuAMP hydrogel, thus releasing the immobilized fluorescent AuAMP NCs, with a release efficiency up to 93.62% within 3 h. On this basis, a fast, sensitive fluorescent detection method for alkaline phosphatase (ALP) is achieved, with a linear detection of ALP in the range of 0.47-10.03 U/L and a limit of detection of 0.09 U/L. This allows the accurate detection of ALP in diluted human serum samples. Last but not least, the ZnSA-AuAMP hydrogel also exhibits peroxidase-like activity with good recyclability, because it is facile to be separated and extracted from catalytic reaction buffer. This work suggests that hydrogels may act as an inexpensive container for controllable regulation of nanozyme activity.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33210150

RESUMO

OBJECTIVES: Pneumomediastinum (PnM) is a rare but life-threatening complication of DM. The present study aims to characterize the long-term prognosis and prognostic factors of DM-associated PnM. METHODS: Inpatients with DM-associated PnM were retrospectively enrolled from two tertiary referral centres for rheumatic disease. The enrolled patients were divided into survivors or non-survivors. Information about the demographics, clinical manifestations, CT scan features, laboratory findings and outcomes were collected from their medical records. A least absolute shrinkage and selection operator regularized Cox regression model was used to select the most relevant factors. Prognosis was analysed using a Kaplan-Meier curve. A Cox proportional hazards model was used to identify independent predictive factors for long-term survival. RESULTS: A total of 62 patients (26 women) with DM-associated PnM were enrolled. The mean age was 44.3 years (s.d. 11.7). The median follow-up duration was 17 days (quartiles 7, 266.5). Thirty-five patients died during follow-up. The survival rates were 75.4% at 1 week, 46.2% at 3 months and 41.9% at 1 year. The Cox proportional hazards model identified the development of fever [hazard ratio (HR) 3.23 (95% CI 1.25, 8.35), P = 0.02] and a decrease in the number of lymphocytes [HR 2.19 (95% CI 1.10, 4.39), P = 0.03] as independent risk factors for death. CONCLUSION: The results suggest poor overall survival among patients with DM-associated PnM. Survival during the first 3 months is crucial for long-term survival. Meanwhile, the development of fever and a decrease in the number of lymphocytes were associated with long-term mortality. Early recognition and prompt treatment of this high-risk group of DM patients is therefore important.

10.
Plant Cell Environ ; 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33131059

RESUMO

Drought is a cyclical phenomenon in natural environments. During dehydration, stomatal closure is mainly regulated by abscisic acid (ABA) dynamics that limit transpiration in seed plants, but following rehydration, the mechanism of gas exchange recovery is still not clear. In this study, leaf water potential (ψleaf ), stomatal conductance (gs ), leaf hydraulic conductance (Kleaf ), foliar ABA level, ethylene emission rate in response to dehydration and rehydration were investigated in four Caragana species with isohydric (Caragana spinosa and C. pruinosa) and anisohydric (C. intermedia and C. microphylla) traits. Two isohydric species with ABA-induced stomatal closure exhibited more sensitive gs and Kleaf to decreasing ψleaf than two anisohydric species which exhibited a switch from ABA to water potential-driven stomatal closure during dehydration. Following rehydration, the recovery of gas exchange was not associated with a decrease in ABA level but was strongly limited by the degradation of the ethylene emission rate in all species. Furthermore, two anisohydric species with low drought-induced ethylene production exhibited more rapid recovery in gas exchange upon rehydration. Our results indicated that ethylene is a key factor regulating the drought-recovery ability in terms of gas exchange, which may shape species adaptation to drought and potential species distribution.

11.
J Asian Nat Prod Res ; : 1-11, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135498

RESUMO

The strain which degraded steviol glycosides to steviol (STE) was screened and isolated from soil samples. A phylogenetic tree was constructed and used to determine the taxonomic status of the strain. 16S rDNA sequence was ultimately used to identify the strain as Microbacterium barkeri XJ. The transformation product was detected and identified as STE by HPLC/LC-MS/IR analysis. The bioconversion rate of 1% (v/v) steviol glycosides (stevioside, rebaudioside A, rebaudioside C) into STE in basic medium were 100% within 24 h, 84 h and 144 h, respectively. The results indicated XJ was more effective than mixed flora in the bioconversion of steviol glycosides to STE.

13.
J Org Chem ; 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33140953

RESUMO

A Ru(II)-catalyzed bisallylation of imidazopyridines with vinylcyclopropanes or vinyl cyclic carbonate has been successfully realized. Notably, pharmacophore imidazopyridine was utilized as an intrinsic directing group, which gave access to value-added bisallylated products in high yields via double tandem C-H and C-C/C-O activation. The current methodology was featured with broad substrate scope, good functional group compatibility, and operational simplicity.

14.
ISA Trans ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33059903

RESUMO

In the hydraulic systems, the non-structural uncertainties such as the nonlinear friction will reduce the tracking accuracy for the hydraulic servo system. In this paper, an incomplete differential-based improved adaptive backstepping integral sliding mode control (ID-BIABISMC) is proposed to realize the position control for the hydraulic servo system based on the friction compensation. The backstepping-based control being integrated the integral sliding mode surface-based sliding mode control with the friction compensation are used to solve the problem of non-structural uncertainty of the hydraulic system. The incomplete differential is introduced to the adaptive update law, by which the low-pass filtering behavior in the incomplete differential is capable of effectively suppressing the interference caused by the pure differential mutation signal. Compared with the traditional adaptive backstepping control (ABC), adaptive sliding mode control (ASMC), the adaptive backstepping sliding mode control (ABSMC) and the proposed adaptive backstepping integral sliding mode control (IABISMC), the experimental results verify the high accuracy tracking performance of the proposed the incomplete differential-based improved adaptive backstepping integral sliding mode control (ID-BIABISMC). For the responses of the sinusoidal signal 40sin(0.2πt+1.5π)+40mm and step signal with 30 mm, the corresponding tracking accuracy for ID-BIABISMC are 0.005 mm and 2.15 mm, respectively.

15.
Mol Ecol Resour ; 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33010101

RESUMO

The blue king crab, Paralithodes platypus, which belongs to the family Lithodidae, is a commercially and ecologically important species. However, a high-quality reference genome for the king crab has not yet been reported. Here, we assembled the first chromosome-level blue king crab genome, which contains 104 chromosomes and an N50 length of 51.15 Mb. Furthermore, we determined that the large genome size can be attributed to the insertion of long interspersed nuclear elements and long tandem repeats. Genome assembly assessment showed that 96.54% of the assembled transcripts could be aligned to the assembled genome. Phylogenetic analysis showed the blue king crab to have a close relationship with the Eubrachyura crabs, from which it diverged 272.5 million years ago. Population history analyses indicated that the effective population of the blue king crab declined sharply and then gradually increased from the Cretaceous and Neogene periods, respectively. Furthermore, gene families related to developmental pathways, steroid and thyroid hormone synthesis, and inflammatory regulation were expanded in the genome, suggesting that these genes contributed substantially to the environmental adaptation and unique body plan evolution of the blue king crab. The high-quality reference genome reported here provides a solid molecular basis for further study of the blue king crab's development and environmental adaptation.

16.
BMC Genomics ; 21(1): 731, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33081725

RESUMO

BACKGROUND: Domestic yaks play an indispensable role in sustaining the livelihood of Tibetans and other ethnic groups on the Qinghai-Tibetan Plateau (QTP), by providing milk and meat. They have evolved numerous physiological adaptations to high-altitude environment, including strong blood oxygen transportation capabilities and high metabolism. The roles of DNA methylation and gene expression in milk production and high-altitudes adaptation need further exploration. RESULTS: We performed genome-wide DNA methylome and transcriptome analyses of breast, lung, and biceps brachii muscle tissues from yaks of different ages. We identified 432,350 differentially methylated regions (DMRs) across the age groups within each tissue. The post-mature breast tissue had considerably more differentially methylated regions (155,957) than that from the three younger age groups. Hypomethylated genes with high expression levels might regulate milk production by influencing protein processing in the endoplasmic reticulum. According to weighted gene correlation network analysis, the "hub" gene ZGPAT was highly expressed in the post-mature breast tissue, indicating that it potentially regulates the transcription of 280 genes that influence protein synthesis, processing, and secretion. The tissue network analysis indicated that high expression of HIF1A regulates energy metabolism in the lung. CONCLUSIONS: This study provides a basis for understanding the epigenetic mechanisms underlying milk production in yaks, and the results offer insight to breeding programs aimed at improving milk production.

17.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(10): 1135-1137, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33059814

RESUMO

A boy, aged 1 month, attended the hospital due to feeding difficulty and hypotonia. He had unusual facial features (prominent forehead, hypertelorism, ptosis of the lateral canthus, thin upper lip, and low-set ears), hypotonia, and a decreased score of neonatal behavioral neurological assessment. Heart ultrasound showed atrial septal defect. Cranial MRI showed widened supratentorial ventricle, cerebral cistern, and subarachnoid space. High-throughput whole-exome sequencing of the boy detected a hemizygous mutation, c.315_320delTGAGCG, in the CCDC22 gene, which came from his mother, while such mutation was not found in his father. The unusual facies, clinical manifestations, and inheritance pattern of this boy were consistent with the manifestations of Ritscher-Schinzel syndrome reported abroad. This is a report for the first time of a case of X-linked recessive Ritscher-Schinzel syndrome caused by the hemizygous mutation c.315_320delTGAGCG in the CCDC22 gene in Chinese population.

18.
J Affect Disord ; 277: 1005-1012, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065809

RESUMO

BACKGROUND: In China, people living with HIV (PLWH) are aging. The study compared prevalence of probable depression between older PLWH and their HIV-negative counterparts, and tested the hypothesis that the between-group difference in depressive symptoms would be mediated by attitudes toward aging. METHODS: With informed consent, a cross-sectional survey was conducted via anonymous face-to-face interviews to 337 and 363 HIV-positive and HIV-negative people aged ≥50, respectively, in Yongzhou City, Hunan, China from December 2017 to August 2018. Depression was measured by the Center for Epidemiologic Studies Depression (CES-D) scale. Attitudes toward aging were measured by the Attitudes to Aging Questionnaire (subdomains: psychosocial loss, physical change, psychological growth). Bootstrapping analyses were performed to test the mediation hypothesis. RESULTS: The prevalence of probable depression (CES-D ≥ 16) was significantly higher in the HIV-positive group than the HIV-negative group (44.8% versus 20.4%). The HIV-positive participants presented more negative attitudes toward aging (in psychosocial loss and physical change) than their HIV-negative counterparts. Negative attitudes toward aging were associated with more depressive symptoms. Overall attitudes toward aging (effect size=41.3%) and the subdomains of psychosocial loss (effect size=38.5%) and physical change (effect size=16.3%) partially mediated the association between HIV status and depressive symptoms, respectively. LIMITATIONS: The cross-sectional design limited the ability of causal inference. Selection bias, information bias, and confounding bias might exist. CONCLUSIONS: Older PLWH might be more depressed than their HIV-negative counterparts in mainland China, partially because they possessed more negative attitudes toward aging. Interventions for depression may include components of improving attitudes toward aging.

19.
Exp Anim ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33071271

RESUMO

Non-human primates are most suitable for generating cervical experimental models, and it is necessary to study the anatomy of the cervical spine in non-human primates when generating the models. The purpose of this study was to provide the anatomical parameters of the cervical spine and spinal cord in long-tailed macaques (Macaca fascicularis) as a basis for cervical spine-related experimental studies. Cervical spine specimens from 8 male adult subjects were scanned by micro-computed tomography, and an additional 10 live male subjects were scanned by magnetic resonance imaging. The measurements and parameters from them were compared to those of 12 male adult human subjects. Additionally, 10 live male subjects were scanned by magnetic resonance imaging, and the width and depth of the spinal cord and spinal canal and the thickness of the anterior and posterior cerebrospinal fluid were measured and compared to the relevant parameters of 10 male adult human subjects. The tendency of cervical parameters to change with segmental changes was similar between species. The vertebral body, spinal canal, and spinal cord were significantly flatter in the human subjects than in the long-tailed macaques. The cerebrospinal fluid space in the long-tailed macaques was smaller than that in the human subjects. The anatomical features of the cervical vertebrae of long-tailed macaques provide a reference for establishing a preclinical model of cervical spinal cord injury.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33034853

RESUMO

In this study, the heterotrophic nitrification-aerobic denitrification activity of Pseudomonas aeruginosa (P-1) strain was investigated, and the N transformation pathway was revealed. The highest removal rates of NH4+, NO3-, and NO2- (9.29, 6.12, and 3.72 mg L-1 h-1, respectively) by this strain were higher than those by most reported bacteria and were achieved when the carbon source was glucose, C/N ratio was 15, pH was 8, temperature was 30 °C, and shaking speed was 200 rpm. The removal order and characteristics of three N sources were investigated in Pseudomonas aeruginosa for the first time. The results revealed that P-1 preferentially nitrified NH4+ and only began to denitrify NO2- and NO3- when NH4+ was almost entirely depleted. Isotopic labeling of N sources revealed that P-1 uses both partial and complete nitrification/denitrification pathways that can operate either simultaneously or independently, depending on the availability of different types of N compounds, with N2 as the final gaseous product and virtually no NO2- accumulation. Moreover, the P-1 strain could convert various nitrogen compounds under high salinity (40 g L-1) and high concentrations of Cu2+, Zn2+, Cr6+, Pb2+, and Cd2+ (50 mg L-1). Therefore, P-1 could be used as an alternative of inorganic N-removal bacteria in practical applications.

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