RSC Advances
·
2022
·Vol. 12
·期 15
·9435-9444
·
IF 4.036
Jiajia Yang,Hongyu Duan,Xiya Wang,Huan Zhang,Zhifeng Zhang
The biological toxicity and eco-environmental risk of metal nanoparticles (MNPs) is closely related to their stability. The stability of MNPs not only depends on their own properties but also on the effects of biological and environmental factors. To better understand the interaction between biological factors and MNPs in aquatic environments, the effects of total rice root exudates (T-RRE) on the aggregation, dissolution and bioaccumulation of Ag nanoparticles (AgNPs) with different surface charges were investigated in detail. Results indicated that T-RRE can induce the aggregation and sedimentation, and hinder the dissolution of polyethyleneimine-coated AgNPs (AgNPs@PEI) with positive surface charges as well as reducing the bioaccumulation of Ag in rice roots. T-RRE had no obvious effect on the dispersion stability of AgNPs@Cit (negatively charged citrate-coated AgNPs) and AgNPs@PVP (near electrically neutral polyvinylpyrrolidone-coated AgNPs), although T-RRE could induce the dissolution of AgNPs@Cit and AgNPs@PVP. In the molecular fractions of T-RRE, high-molecular-weight root exudates (H-RRE) play a key role in inducing the aggregation of AgNPs@PEI and hindering the bioaccumulation of Ag in rice roots. Compared with H-RRE, low-molecular-weight root exudates (L-RRE) can promote the dissolution of AgNPs@Cit and AgNPs@PVP, but it can obviously promote silver accumulation in rice roots. The difference in charge intensity between L-RRE and T-RRE plays a key role in inducing the aggregation and dissolution of AgNPs with different charges. These findings provide a foundation for investigation of the interactions between rice root exudates and nanoparticles with different surface charges in complex environmental systems.
研究领域:
环境科学
·
纳米技术
·
植物生物学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biomed Research International
·
2018
·
IF 2.583
Guan-Xi Li,Xiao-Qin Wu,Jian-Ren Ye,He-Chuan Yang
The objective of this study was to investigate whether plant-bacteria interaction affects the secretion of organic acids by both organisms and to assess whether the production of IAA by the bacterium increases the secretion of organic acids by root exudates, and if the stress produced by low available phosphorus (P) affects the production of organic acids by bacteria, by roots, or by root exudates in presence of bacterial cultures. With this purpose, we used as a biological model poplar plants and one strain of Burkholderia multivorans able to solubilize P. High performance liquid chromatography was utilized to measure organic acids. The tests, the inductive effects of exogenous indole-3-acetic acid (IAA) on secretion of organic acids, the 2 × 4 × 2 factorial design experiment, and the ability of organic acids to solubilize tricalcium phosphate were performed to investigate the interactive effects. The results showed that, after B. multivorans WS-FJ9 interacted with the poplar root system, the key phosphate-solubilizing driving force was gluconic acid (GA) which was produced in three ways: (1) secreted by the root system in the presence of IAA produced by B. multivorans WS-FJ9; (2) secreted by B. multivorans WS-FJ9; and (3) secreted by the poplar root system in the presence of phosphorus stress. When phosphorus stress was absent, the GA was produced as outlined in (1) and (2) above. These results demonstrated that inoculating B. multivorans WS-FJ9 into the poplar root system could increase the amount of GA secretion and implied that the interaction between B. multivorans WS-FJ9 and the poplar root system could contribute to the increase of P available fraction for poplar plants.
研究领域:
植物学
·
微生物学
·
土壤科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF PLANT GROWTH REGULATION
·
2017
·Vol. 37
·期 3
·745-754
·
IF 2.073
Zhang Qi,Li Li,Li Jiayu,Wang Haibin,Fang Changxun,Yang Xiaoyan,He Haibin
An allelopathic rice PI312777 and a non-allelopathic rice Lemont were hydroponically cultured and treated with extracts of seeds and tissues and root exudates of barnyard grass ( Echinochloa crus-galli , BYG) to induce an allelopathic response. The results of bioassays showed that the % inhibition of two rice leaf extracts was significantly ( p < 0.05) increased by treatment with BYG root exudates. This induced trait was dosage- and time-dependent. The highest % inhibition for both PI312777 and Lemont was obtained following treatment with 15 mL of BYG root exudates for 2 days. Under these conditions, total allelopathy (TA) values of PI312777 on root length, plant height, and plant dry weight of BYG were 73.39, 68.01, and 70.42%, respectively, and induced allelopathy (IA) values were 21.53, 17.04, and 16.62%, respectively, accounting for 24–29% of TA. Correspondingly, TA values of Lemont were 28.38, 21.38, and 23.38%, respectively, and IA values were 14.49, 11.37, and 12.11%, respectively, accounting for 51–53% of TA. The % inhibition of two rice culture solutions was in agreement with the results of their leaf extracts. The total contents of 7 phenolic acids in the culture solutions of PI312777 and Lemont were 2.18 and 1.47 times, respectively, as much as those in the control solutions. The phenylalanine ammonia-lyase ( PAL ) gene in PI312777 leaves was significantly up-regulated after induction treatments. The results indicated that rice allelopathy is a chemical induction mechanism, and confirmed that chemical induction to raise rice allelopathy is a practical and feasible method.
研究领域:
植物学
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农业科学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2017
·
IF 4.208
Zhenzhen Huang,Piao Xu,Guiqiu Chen,Guangming Zeng,Anwei Chen,Zhongxian Song,Kai He,Lei Yuan,Hui Li,Liang Hu
This study investigated the influence of silver ions (Ag + ) on the cytotoxicity of silver nanoparticles (AgNPs) in Phanerochaete chrysosporium and noted the degree of extracellular secretions in response to the toxicant's stress. Oxalate production was elicited with moderate concentrations of 2,4-dichlorophenol (2,4-DCP) and AgNPs reaching a plateau at 10 mg/L and 10 μM, respectively. Increased oxalate accumulation was accompanied by higher activities of manganese peroxidase (MnP) and lignin peroxidase (LiP). However, the secretion of oxalate, MnP and LiP was significantly inhibited owing to Ag + incorporation into AgNP solution. Production of extracellular polymeric substances (EPS) significantly elevated with an increase in 2,4-DCP concentrations; however, after 24 h of exposure to 100 mg/L 2,4-DCP, an obvious decrease in EPS occurred, indicating that part of EPS could be consumed as carbon and energy sources to ameliorate biological tolerance to toxic stress. Furthermore, AgNP-induced “particle-specific” cytotoxicity was substantially enhanced with additional Ag + as evidenced by its significant negative impact on cellular growth, plasma membrane integrity, and morphological preservation compared with AgNPs at equal Ag concentration.
研究领域:
微生物学
·
环境科学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
PNAS Nexus
·
2024
·Vol. 3
·期 4
·
IF 2.2
Sun Kai,Dai Ling-Zhi,Chen Mei-Hua,Si You-Bin,Fang Guo-Dong,Li Shun-Yao,Yu Han-Qing
Enzymatic humification plays a crucial biogeochemical role in eliminating steroidal estrogens and expanding organic carbon stocks. Estrogenic contaminants in agroecosystems can be taken up and acropetally translocated by crops, but the roles of laccase-triggered rhizospheric humification (L-TRH) in pollutant dissipation and plant uptake remain poorly understood. In this study, the laccase-induced decontamination and humification mechanisms of 17β-estradiol (E2) in water–crop media were investigated by performing greenhouse pot experiments with maize seedlings (Zea mays L.). The results demonstrated that L-TRH effectively dissipated E2 in the rhizosphere solution and achieved the kinetic constants of E2 dissipation at 10 and 50 μM by 8.05 and 2.75 times as much as the treatments without laccase addition, respectively. The copolymerization of E2 and root exudates (i.e. phenols and amino acids) consolidated by L-TRH produced a larger amount of humified precipitates with the richly functional carbon architectures. The growth parameters and photosynthetic pigment levels of maize seedlings were greatly impeded after a 120-h exposure to 50 μM E2, but L-TRH motivated the detoxication process and thus mitigated the phytotoxicity and bioavailability of E2. The tested E2 contents in the maize tissues initially increased sharply with the cultivation time but decreased steadily. Compared with the treatment without laccase addition, the uptake and accumulation of E2 in the maize tissues were obviously diminished by L-TRH. E2 oligomers such as dimer, trimer, and tetramer recognized in the rhizosphere solution were also detected in the root tissues but not in the shoots, demonstrating that the acropetal translocation of E2 oligomers was interrupted. These results highlight a promising strategy for decontaminating estrogenic pollutants, boosting rhizospheric humification, and realizing low-carbon emissions, which would be beneficial for agroenvironmental bioremediation and sustainability.
研究领域:
环境科学
·
农业科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
High Voltage
·
2024
·
IF 4.4
Shifang Yang,Zexuan Zhang,Qianpeng Hou,Yunpeng Liu,Chi Gong
The authors explore the limitations of silicone rubber (SR) in tropical environments due to its lack of antimicrobial activity. The use of a 2-methylisothiazol-3(2H)-one compound with 5-chloro-2-methylisothiazol-3(2H)-one is proposed as an efficient and environmentally friendly antimicrobial agent to enhance the fungistatic properties of SR. The fungicide added specimen was obtained by directly adding a quantitative amount of isothiazolinone to the polymer system. Through an in-depth analysis of the material properties of MCMSR, the form in which 2-methyl-4-isothiazolin-3-one/5-chloro-2-methyl-4-isothiazolin-3-one (MIT/CMIT) exists in the molecular structure of the SR crosslink system was carefully explored. The accelerated hydrolysis process of polysiloxane, which caused fungi secretion, was proven to be suppressed due to the effects of MIT/CMIT. The antimicrobial mechanism of isothiazolinone in preventing microbial growth was interpreted as the apoptosis and necrosis procedures of Aspergillus niger cells, which were verified by flow cytometry results. By choosing the appropriate concentration of isothiazolinone, the original properties of the SR were successfully maintained while effectively preventing the aggregation of isothiazolinone. This opens up a new research direction and application prospect for the antimicrobial modification of SR.
研究领域:
材料科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
Microbiology Spectrum
·
2024
·
IF 3.7
Yanjun Xie,Fangyi Xu,Huali Dong,Jianfeng Mao,Chuanling Zhang
The colonization of Enterococcus in the female vagina leads to neonatal and pediatric enterococcal septicemia. Linezolid (LZD) is a kind of mainstream drug for treating multidrug-resistant Gram-positive infections. OptrA is the main LZD-resistance gene at Enterococci in human isolates. It is essential to explore the prevalence of optrA-carrying Enterococcus in vaginal secretions of late pregnant women and the drug resistance of optrA. From May to June 2023, this study recruited 340 volunteers in late pregnancy (35–40 weeks of pregnancy) to provide non-repetitive vaginal discharge samples. Luria-Bertani broth and florfenicol (10 µg/mL) were used to enrich bacteria. Enterococci was identified through time-of-flight mass spectrometry. Additionally, antimicrobial susceptibility, polymerase chain reaction, and next-generation sequencing assays were applied to this study. Fifty-four optrA-carrying Enterococcus strains were obtained, the proportion of the whole vagina of late pregnant women was 15.88% (54 out of 340), and Enterococcus faecalis account the highest proportion. All optrA-carrying Enterococcus were resistant to at least three drugs. Tetracycline, chloramphenicol, erythromycin, and LZD have higher bacterial resistance rates. Genetic environment analysis revealed that IS1216E, fexA, and erm(A) may synergistically exert multidrug resistance with optrA. It is necessary to strengthen the surveillance of optrA-carrying Enterococcus in pregnant women. This study provides scientific support for controlling hospital infections and managing antibiotic-resistant bacteria, and provides a scientific basis for rational clinical medication.
研究领域:
微生物学
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妇产科学
·
感染病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Mengjun Yun,Yu Xiong,Zhuobing Wang,Lianjie Xie,Hanwen Ye,Xiaofang Yuan,Weiyi He,Binqing Chen,Zhanjun Lu,Wei Chen
Plants perceive proteins from insect-derived oral secretion (OS) and regulate the classical endogenous hormone jasmonic acid to resist insects, but the role of abscisic acid (ABA) in this process is poorly understood. In this study, we used the specialist herbivorous caterpillar Plutella xylostella and cruciferous plants as a model to investigate how the ABA hormone responds to the OS and its core peptide from the insect. Through proteomics and Western blotting analysis, glucosinolate sulfatase 1 (GSS1) was identified in OS. Yeast library screening revealed that GSS1 and its 28-amino-acid core peptide (GSS1-P1) interact with ABA biosynthetic enzyme ABA1. Arabidopsis overexpressing GSS1 and plants treated with synthetic GSS1-P1 showed elevated ABA levels. Transcriptome analysis and RT-qPCR confirmed that GSS1-P1 upregulates WRKY18 and ABA1 expression, modulating ABA production. Both GSS1-P1 application and optimal ABA concentrations enhanced plant resistance to herbivory. Our study shows that GSS1 and its peptide stimulate ABA production, boosting plant–insect resistance and highlighting ABA’s potential role in pest-stress response.
研究领域:
植物学
·
分子生物学
·
昆虫学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-10
·
IF 4.259
Lu Hainan,Sun Jianteng,Zhu Lizhong
Root exudates play an important role in the phytoremediation of soils contaminated by organic pollutants, but how root exudate components affect the remediation process is not well understood. In this study, we explored the effects and mechanisms of the major root exudates, including glucose, organic acids, and serine, in the rhizoremediation of pyrene-contaminated soil. The results showed that glucose increased the degradation of pyrene (54.3 ± 1.7%) most significantly compared to the organic acids (45.5 ± 2.5%) and serine (43.2 ± 0.1%). Glucose could significantly facilitate the removal of pyrene in soil through promoting dehydrogenase activity indicated by a positive correlation between the removal efficiency of pyrene and the soil dehydrogenase activity ( p < 0.01). Furthermore, root exudates were able to change soil microbial community, particularly the bacterial taxonomic composition, thereby affecting the biodegradation of pyrene. Glucose could alter soil microbial community and enhance the amount of Mycobacterium markedly, which is dominant in the degradation of pyrene. These findings provide insights into the mechanisms by which root exudates enhance the degradation of organic contaminants and advance our understanding of the micro-processes involved in rhizoremediation.
研究领域:
环境科学
·
微生物学
·
植物学
✓ 已验证
DOI
高影响因子
SOIL BIOLOGY & BIOCHEMISTRY
·
2025
·
IF 10.3
Zixuan Zhao,Bin Luo,Tao Cao,Tongtong Bai,Yifan Sun,Hengrui Liu,Li Zhang,Jun Xie,Jun Wang,Huakang Li,Zichen Duan,Zixuan Gao,Xiaojuan Wang,Jie Gu,Xun Qian,James M. Tiedje
The transmission and transformation patterns of antibiotic resistance genes (ARGs) in the soil-onion continuum under the application of organic fertilizers in actual agricultural cultivation are still unknown. This study systematically analyzed the occurrence characteristics of ARGs in soil and onion (roots and bulbs) under the application of organic fertilizer from livestock manure, and revealed the response mechanism of phenolic metabolites in roots. The results showed that fertilization promoted the enrichment of ARGs in the soil and onions. The abundance of ARGs in the bulbs of the pig manure and sheep manure treatment groups was 4 times and 2 times as high as that in the unfertilized group, respectively. In comparison to the bulbs, a higher abundance of ARGs was observed in the roots of onions. The 11 ARGs, including high-risk variants such as tetX and mexE , were detected co-occurring in both onion tissues and the surrounding soil. Fertilization treatment significantly changed the community composition of ARGs-related host bacteria in onion tissues. Livestock manure-based organic fertilizers elevated the potential exposure risk of ARGs in bulbs by more than 20%. Five strains of multidrug-resistant endophytic bacteria (including Streptomyces and Pseudomonas ) were isolated from the main edible parts of onion bulbs. It is worth noting that this study found that kaempferol (35-140 μg/L) and p-coumaric acid (2.5-10 μg/L) significantly enhanced the conjugation and transfer of the RP4 plasmid in the onion endophytes ( Bacillus sp. and Paenibacillus sp.) and soil microbial communities. Root exudates were the predominant factors regulating the transmission of ARGs in the soil-onion system.
研究领域:
环境科学
·
微生物学
·
农业科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2024
·
IF 8
Jie Zhong,Hang Wei,Jian-Xiong Xie,Yu-Hui Wu,Bing Tang,Qi Zou,Peng-Ran Guo,Zhi-Liang Chen
The use of wetland plants in the context of phytoremediation is effective in the removal of antibiotics from contaminated water. However, the effectiveness and efficiency of many of these plants in the removal of antibiotics remain undetermined. In this study, the effectiveness of two plants— Phragmites austr alis and Iris pseudacorus —in the removal of tetracycline (TC) in hydroponic systems was investigated. The uptake of TC at the roots of I. pseudacorus and P. australis occurred at concentrations of 588.78 and 106.70 μg/g, respectively, after 7-day exposure. The higher uptake of TC in the root of I. pseudacorus may be attributed to its higher secretion of root exudates , which facilitate conditions conducive to the reproduction of microorganisms. These rhizosphere-linked microorganisms then drove the TC uptake, which was higher than that in the roots of P. australis . By elucidating the mechanisms underlying these uptake-linked outcomes, we found that the uptake of TC for both plants was significantly suppressed by metabolic and aquaporin inhibition, suggesting uptake and transport of TC were active (energy-dependent) and passive (aquaporin-dominated) processes, respectively. The subcellular distribution patterns of I. pseudacorus and P. australis in the roots were different, as expressed by differences in organelles , cell wall concentration levels, and transport-related dynamics. Additionally, the microbe-driven enhancement of the remediation capacities of the plants was studied comprehensively via a combined microbial-phytoremediation hydroponic system. We confirmed that the microbial agents increased the secretion of root exudates, promoting the variation of TC chemical speciation and thus enhancing the active transport of TC. These results contribute toward the improved application of wetland plants in the context of antibiotic phytoremediation .
研究领域:
环境科学
·
植物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Pollutants and Bioavailability
·
2019
·
IF 0
Xiaona Li,Yang Song,Yongrong Bian,Fang Wang,Chenggang Gu,Xinglun Yang,Xin Jiang
The effect of oxalic acid on phenanthrene sorption was varied from that on pyrene sorption. 1.0 mg L-1 of oxalic acid inhibited phenanthrene sorption, whereas 20, 50 and 100 mg L-1 of oxalic acid enhanced the sorption. However, pyrene sorption onto biochar was all inhibited among different concentrations of oxalic acid. New functional groups and increased polarity were observed in the biochar coexisted with oxalic acid, moreover, a high concentration of oxalic acid led to an increased specific surface area of the biochar. These changed factors contributed to biochar sorption to phenanthrene, which was dominated by surface adsorption. Weakened aromaticity and increased release of dissolved organic carbon from biochar may have been the main reason for inhibited pyrene sorption onto biochar by oxalic acid. Therefore, this study suggested that root exudates could greatly influence the sorption behavior of biochar towards PAHs in soil rhizosphere, which deserves attention in agricultural systems.
研究领域:
环境科学
·
农业科学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）