Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Environ Pollut ; 355: 124199, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788990

RESUMO

Phytoremediation has become famous for removing particulate matter (PM) and volatile organic compounds (VOCs), but the ability is affected by plant health. Lately, the priming technique was a simple approach to studying improving plant tolerance against abiotic stress by specific metabolites that accumulated, known as "memory", but the mechanism underlying this mechanism and how long this "memory" was retained in the plant was a lack of study. Sansevieria trifasciata was primed for one week for PM and VOC stress to improve plant efficiency on PM and VOC. After that, the plant was recovered for two- or five-weeks, then re-exposed to the same stress with similar PM and VOC concentrations from cigarette smoke. Primed S. trifasciata showed improved removal of PMs entirely within 2 h and VOC within 24 h. The primed plant can maintain a malondialdehyde (MDA) level and retain the "memory" for two weeks. Metabolomics analysis showed that an ornithine-related compound was accumulated as a responsive metabolite under exposure to PM and VOC stress. Exogenous ornithine can maintain plant efficiency and prevent stress by increasing proline and antioxidant enzymes. This study is the first to demonstrate plant "memory" mechanisms under PM and VOC stress.


Assuntos
Biodegradação Ambiental , Material Particulado , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/metabolismo , Poluentes Atmosféricos/metabolismo , Asparagaceae/metabolismo , Malondialdeído/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-37428325

RESUMO

Particulate matters (PM) and volatile organic compounds (VOCs) are the sources of toxic substances that hurt human health and can cause human carcinogens. An active living wall was applied to reduce PM and VOC contamination, while Sansevieria trifasciata cv. Hahnii, a high-performance plant for VOC removal, was selected to grow on the developing wall and used to treat PM and VOCs. The active living wall operating in a 24 m3 testing chamber showed the ability to remediate more than 90% PM within 12 h. The VOC removal can be approximately 25-80% depending on each compound. In addition, the suitable flow velocity of the living wall was also investigated. The flow rate of 1.7 m3 h-1 in front of the living wall was found as the best inlet flow velocity for the developed active living wall. The suitable condition for PM and VOC removal in the active living wall application on the real side was presented in this study. The result confirmed that the application of an active living wall for PM phytoremediation can be an alternative effective technology.

3.
Chemosphere ; 295: 133919, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35143856

RESUMO

Botanical biofilters can effectively remove indoor air pollution. However, to apply botanical biofilters in situ, the distance of botanical biofilter to the pollutants and airflow pattern can be important factors impacting efficiency. This study examined the removal efficiency of particulate matters (PMs) and volatile organic compounds (VOCs) from cigarette smoke, such as formaldehyde and acetone, at various distances (100 cm, 175 cm, 240 cm, and 315 cm) using a Sansevieria trifasciata botanical biofilter. The botanical biofilter was placed inside a testing room (24 m3) and exposed to cigarette smoke. The pollutants removal efficiency was evaluated for six cycles (24 h/cycle) and one cycle as a recovery period where botanical biofilter was placed under normal conditions for 30 days. Results showed that the botanical biofilter could remove 140-250 µg m-3, 147-257 µg m-3, 212-455 µg m-3 for PM1, PM2.5, and PM10, respectively, at 8 h. Total VOCs, formaldehyde, and acetone removal were 40%-65%, 46%-69%, and 31%-61% at 24 h. PMs and VOCs removal efficiency can be affected by both distance and pattern of airflow in the testing room. The highest PM1 and PM2.5 elimination appeared at 240 cm and 315 cm, while VOCs removal was high at 100 cm. Botanical biofilter creates airflow vortices around 100 cm, indicating low removal of PMs. This is the first study that demonstrated the effect of airflow patterns on different pollutants removal efficiency.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Fumar Cigarros , Sansevieria , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Filtração , Material Particulado/análise , Compostos Orgânicos Voláteis/análise
4.
Environ Sci Pollut Res Int ; 28(1): 538-546, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32812163

RESUMO

Indoor air pollutants comprise both polar and non-polar volatile organic compounds (VOCs). Indoor potted plants are well known for their innate ability to improve indoor air quality (IAQ) by detoxification of indoor air pollutants. In this study, a combination of two different plant species comprising a C3 plant (Zamioculcas zamiifolia) and a crassulacean acid metabolism (CAM) plant (Sansevieria trifasciata) was used to remove polar and non-polar VOCs and minimize CO2 emission from the chamber. Z. zamiifolia and S. trifasciata, when combined, were able to remove more than 95% of pollutants within 48 h and could do so for six consecutive pollutant's exposure cycles. The CO2 concentration was reduced from 410 down to 160 ppm inside the chamber. Our results showed that using plant growth medium rather than soil had a positive effect on decreasing CO2. We also re-affirmed the role of formaldehyde dehydrogenase in the detoxification and metabolism of formaldehyde and that exposure of plants to pollutants enhances the activity of this enzyme in the shoots of both Z. zamiifolia and S. trifasciata. Overall, a mixed plant of Z. zamiifolia and S. trifasciata was more efficient at removing mixed pollutants and reducing CO2 than individual plants.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluentes Ambientais , Sansevieria , Compostos Orgânicos Voláteis , Poluição do Ar em Ambientes Fechados/análise , Biodegradação Ambiental , Dióxido de Carbono , Formaldeído , Tolueno
5.
J Environ Sci (China) ; 94: 161-170, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563480

RESUMO

Phytoremediation is a sustainable remedial approach for removing benzene from environment. Plant associated bacteria could ameliorate the phytotoxic effects of benzene on plant, although the specificity of these interactions is unclear. Here, we used proteomics approach to gain a better understanding of the mechanisms involved in plant-bacteria interactions. Plant associated bacteria was isolated and subsequently inoculated into the sterilized Helianthus annuus, and the uptake rates of benzene by these inoculated plants were evaluated. At the end of the experiment, leaves and roots proteins were analyzed. The results showed inoculated H. annuus with strain EnL3 removed more benzene than other treatments after 96 h. EnL3 was identified as Enterobacter sp. according to 16S rDNA analysis. Based on the comparison of proteins, 62 proteins were significantly up or down regulated in inoculated leaves, while 35 proteins were significantly up or down regulated in inoculated roots. Furthermore, there were 4 and 3 identified proteins presented only in inoculated H. annuus leaves and roots, respectively. These proteins involved in several functions including transcription and translation, photosynthesis, and stress response. The network among anti-oxidant defense system, protein synthesis, and photosynthetic electron transfer are involved in collaboratively activate the benzene uptake and stress tolerance in plant.


Assuntos
Benzeno , Proteômica , Bactérias , Folhas de Planta , Proteínas de Plantas , Raízes de Plantas
6.
Chemosphere ; 239: 124724, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505447

RESUMO

Combination of sulfuric acid modified bagasse activated carbon-bone biochar beads and Acinetobacter indicus screened from petroleum contaminated soil was the best condition for gaseous methyl tert-butyl ether (MTBE) removal. It was found that H2SO4 modified bagasse AC in powder form had higher adsorption capacity (989.33 mg g-1) than that in bead form (1.94 mg g-1). In addition, bone biochar in powder form (3.51 mg g-1) also had higher adsorption capacity than that in bead form (1.63 mg g-1). This was the fact that material beads contained high moisture content that inhibited the penetration of gaseous MTBE into the material. And a mixed material of H2SO4 modified bagasse AC-bone biochar beads had the highest adsorption capacity (2.22 mg g-1) compared to individual H2SO4 modified bagasse AC beads (1.94 mg g-1) and bone biochar beads (1.63 mg g-1) due to a mixed material had more rough surface and high surface area on its material. So, gaseous MTBE can penetrate through this material more easily. Although the maximum adsorption capacity of H2SO4 modified bagasse AC in powder form was the highest but microorganism cannot sustain and survive in this form for a long time. Therefore, the material beads were more suitable for microorganism to grow and degrade gaseous MTBE. Microorganism can degrade MTBE and caused no secondary wastes. Moreover, A. indicus was a novel strain for MTBE removal that has not been previously reported. Therefore, a combination of A. indicus-mixed material beads was a good choice for MTBE removal in a biofilter system.


Assuntos
Acinetobacter/metabolismo , Celulose/química , Carvão Vegetal/química , Éteres Metílicos/química , Acinetobacter/isolamento & purificação , Adsorção , Biodegradação Ambiental , Células Imobilizadas , Poluição Ambiental , Gases , Éteres Metílicos/isolamento & purificação , Éteres Metílicos/metabolismo , Petróleo , Microbiologia do Solo , Ácidos Sulfúricos/química , Gerenciamento de Resíduos/métodos
7.
Environ Technol ; 41(27): 3607-3618, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31081467

RESUMO

Coir pith glucose syrup beads were used as a supporter in a biofilter system. The modified coir pith beads provided a carbon source and controlled humidity for microorganism growth for long-term operation without external nutrient supplementation. For the screening, Bacillus spp. were immobilised on coir pith beads and used for benzene bioremediation. The result showed that coir pith beads immobilised with Bacillus megaterium can remove on average 85-100% of the benzene (215-day operation). In addition, B. megaterium presented the ability to transform benzene to catechol. For an up-scaled application, a 25-L biofilter system was developed and tested in a closed 24-m3 container re-injected with 0.6 ppm benzene for 8 cycles. The system presented the ability to remove 100% of the benzene. This biofilter has the potential to be applied in a real benzene-contaminated site.


Assuntos
Bacillus megaterium , Benzeno , Adsorção , Biodegradação Ambiental , Glucose , Lignina/análogos & derivados , Nutrientes
8.
Sci Total Environ ; 662: 805-815, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30708296

RESUMO

Benzene, a hydrophobic xenobiotic, induces cell damage in both humans and plants. Due to its volatilization, benzene is an airborne environmental problem. The potential of an exogenous bioactive brassinosteroid phytohormone to enhance benzene removal for phytoremediation was investigated. Chlorophytum comosum had higher brassinosteroids content under benzene stress. Plant treated with 24-epibrassinolide (EBR) removed significantly more gaseous benzene than untreated plants under both light and dark conditions at an initial benzene of 12.75 µmol in the systematic chambers (P < 0.05). Although benzene increased malondialdehyde in plant tissue, EBR-treated plants lowered this lipid peroxidation by enhancing their antioxidant content and increasing benzene detoxification-related genes expression, including ascorbic acid (AsA), homogentisate phytyltransferase (HPT), and glutathione synthethase (GS). This contributed to maintaining higher photosynthetic performances. Moreover, EBR-treated plants had higher gene expression of ferredoxin-NADP reductase (FNR) and glucose-6-phosphate 1-dehydrogenase (G6PDH), thus promoting NADPH biosynthesis to cope with benzene under light and dark conditions, respectively. Further, higher glutathione biosynthesis promoted more glutathione conjugate of benzene products including S-phenylcysteine (SPC) in EBR-treated plants. Hence, application of exogenous EBR as foliar spray provided for enhanced benzene detoxification via antioxidant content, benzene detoxification-related genes and benzene conjugation products with glutathione (GSH) and consequently greater gaseous benzene removal.


Assuntos
Asparagaceae/metabolismo , Benzeno/metabolismo , Brassinosteroides/farmacologia , Poluentes Ambientais/metabolismo , Glutationa/metabolismo , Esteroides Heterocíclicos/farmacologia , Asparagaceae/efeitos dos fármacos , Asparagaceae/genética , Biodegradação Ambiental , Escuridão , Genes de Plantas/genética , Luz , Peroxidação de Lipídeos/efeitos dos fármacos , Desintoxicação Metabólica Fase II , Fotossíntese/efeitos dos fármacos
9.
Plant Physiol Biochem ; 130: 181-191, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29990771

RESUMO

This study was performed to determine the effect of plant-endophytic Enterobacter sp. EN2 interactions and blue-red LED light conditions on gaseous benzene removal by plants. It was found that under consecutive benzene fumigation for three cycles (18 days), inoculation of the strain EN2 into sterilized and non-sterilized native C. comosum resulted in significantly increased gaseous benzene removal compared to that in non-inoculated groups under the same light conditions (P < 0.05). Remarkably, EN2 colonization in inoculated plants under LED conditions was higher than under fluorescence conditions as the EN2 could grow better under LED conditions. Strain EN2 possesses NADPH that is used to facilitate benzene degradation and modulate plant growth under benzene stress by bacterial IAA production and ACC deaminase activity; higher IAA and lower ethylene levels were found in inoculated plants compared to non-inoculated ones. These contributed to better benzene removal efficiency. Interestingly, under fumigation for 16 cycles (67 days), there was no difference in gaseous benzene removal between inoculated plants and non-inoculated plants under the same light conditions at initial benzene concentrations of 5 ppm. This is probably due to EN2 reaching maximum growth under all treatments. However, C. comosum exhibited better benzene removal under LED conditions than under fluorescence conditions during 16 cycles, possibly due to better photosynthetic performance and plant growth, leading to more NADPH, and eventually enhanced benzene removal efficiency. Hence, the most efficient acceleration of benzene removal was provided by inoculation of strain EN2 onto C. comosum under blue-red LED light conditions.


Assuntos
Asparagaceae/microbiologia , Asparagaceae/efeitos da radiação , Benzeno/metabolismo , Enterobacter/fisiologia , Enterobacter/efeitos da radiação , Luz , Poluentes Atmosféricos , Biodegradação Ambiental , Endófitos , Fotossíntese , Estresse Fisiológico , Simbiose , Fatores de Tempo
10.
Environ Sci Pollut Res Int ; 25(26): 25690-25701, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28480489

RESUMO

This study analyzed the application of three microorganism inoculums, including Bacillus subtilis, Bacillus cereus, and commercial effective microorganism (EM) solution in order to determine cadmium (Cd) reduction in rice (Oryza sativa L.) and rice growth promotion. Rice was grown in Cd-contaminated soil (120 mg/kg) and selected microorganisms were inoculated. Cd concentration and rice weight were measured at 45 and 120 days of the experiment. The result showed that B. subtilis inoculation into rice can highly reduce Cd accumulation in every part of rice roots and shoots (45 days), and grains (120 days). This species can effectively absorb Cd compared to other inoculums, which might be the main mechanism to reduce Cd transportation in rice plants. Interestingly, plants that were inoculated with bacterial species individually harbored higher calcium (Ca) and magnesium (Mg) accumulation; B. subtilis-inoculated plants had the highest levels of Ca and Mg compared to other inoculated ones. Moreover, inoculating rice plants with these microorganisms could increase the dry weight of the plant and protect them from Cd stress because all the inoculums presented the ability to solubilize phosphate, produce indole-3-acetic acid (IAA), and control ethylene levels by 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. After 120 days, quantification of each inoculum by quantitative polymerase chain reaction (qPCR) confirmed the root colonization of bacterial species, with B. subtilis showing higher 16S rRNA gene copy numbers than the other species. B. subtilis was classified as a non-human pathogenic strain, reassuring the safe application of this plant growth-promoting bacterium as a crop inoculum.


Assuntos
Bactérias/metabolismo , Cádmio/metabolismo , Oryza/efeitos dos fármacos , Oryza/metabolismo , Microbiologia do Solo , Poluentes do Solo/toxicidade , Transporte Biológico , Cádmio/análise , Cádmio/toxicidade , Poluição Ambiental/análise , Etilenos , Ácidos Indolacéticos , Oryza/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , RNA Ribossômico 16S/genética , Poluentes do Solo/análise
11.
Plant Physiol Biochem ; 120: 95-102, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28992544

RESUMO

Benzene, a carcinogenic compound, has been reported as a major indoor air pollutant. Chlorophytum comosum (C. comosum) was reported to be the highest efficient benzene removal plant among other screened plants. Our previous studies found that plants under light conditions could remove gaseous benzene higher than under dark conditions. Therefore, C. comosum exposure to airborne benzene was studied under different light quality at the same light intensity. C. comosum could remove 500 ppm gaseous benzene with the highest efficiency of 68.77% under Blue:Red = 1:1 LED treatments and the lowest one appeared 57.41% under white fluorescent treatment within 8 days. After benzene was uptaken by C. comosum, benzene was oxidized to be phenol in the plant cells by cytochrome P450 monooxygenase system. Then, phenol was catalyzed to be catechol that was confirmed by the up-regulation of phenol 2-monooxygenase (PMO) gene expression. After that, catechol was changed to cic, cis-muconic acid. Interestingly, cis,cis-muconic acid production was found in the plant tissues higher than phenol and catechol. The result confirmed that NADPH-cytochrome P450 reductase (CPR), cytochrome b5 (cyt b5), phenol 2-monooxygenase (PMO) and cytochrome P450 90B1 (CYP90B1) in plant cells were involved in benzene degradation or detoxification. In addition, phenol, catechol, and cis,cis-muconic acid production were found under the Blue-Red LED light conditions higher than under white fluorescent light conditions due to under LED light conditions gave higher NADPH contents. Hence, C. comosum under the Blue-Red LED light conditions had a high potential to remove benzene in a contaminated site.


Assuntos
Asparagaceae/metabolismo , Benzeno , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Luz , Proteínas de Plantas/biossíntese , Benzeno/metabolismo , Benzeno/farmacologia , Biodegradação Ambiental
12.
Plant Physiol Biochem ; 114: 1-9, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28246037

RESUMO

Deeper understanding of plant-endophyte interactions under abiotic stress would provide new insights into phytoprotection and phytoremediation enhancement. Many studies have investigated the positive role of plant-endophyte interactions in providing protection to the plant against pollutant stress through auxin (indole-3-acetic acid (IAA)) production. However, little is known about the impact of endophytic colonization patterns on plant stress response in relation to reactive oxygen species (ROS) and IAA levels. Moreover, the possible effect of pollutant phase on plant stress response is poorly understood. Here, we elucidated the impact of endophytic colonization patterns on plant stress response under airborne formaldehyde compared to formaldehyde-contaminated soil. ROS, tryptophan and IAA levels in the roots and shoots of endophyte-inoculated and non-inoculated plants in the presence and absence of formaldehyde were measured. Strain-specific quantitative polymerase chain reaction (qPCR) was used to investigate dynamics of endophyte colonization. Under the initial exposure to airborne formaldehyde, non-inoculated plants accumulated more tryptophan in the shoots (compared to the roots) to synthesize IAA. However, endophyte-inoculated plants behaved differently as they synthesized and accumulated more tryptophan in the roots and, hence, higher levels of IAA accumulation and exudation within roots which might act as a signaling molecule to selectively recruit B. cereus ERBP. Under continuous airborne formaldehyde stress, higher levels of ROS accumulation in the shoots pushed the plant to synthesize more tryptophan and IAA in the shoots (compared to the roots). Higher levels of IAA in the shoots might act as the potent driving force to relocalize B. cereus ERBP from roots to the shoots. In contrast, under formaldehyde-contaminated soil, B. cereus ERBP colonized root tissues without moving to the shoots since there was a sharp increase in ROS, tryptophan and IAA levels of the roots without any significant increase in the shoots. Pollutant phase affected endophytic colonization patterns and plant stress responses differently.


Assuntos
Araceae/fisiologia , Bacillus cereus/fisiologia , Endófitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Poluentes Atmosféricos/toxicidade , Araceae/efeitos dos fármacos , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/genética , Clorofila/metabolismo , Endófitos/efeitos dos fármacos , Formaldeído/toxicidade , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Poluentes do Solo/toxicidade , Triptofano/metabolismo
13.
Plant Physiol Biochem ; 111: 284-294, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27987473

RESUMO

Better understanding of plant-bacteria interactions under stress is of the prime importance for enhancing airborne pollutant phytoremediation. No studies have investigated plant-epiphyte interactions compared to plant-endophyte interactions under airborne formaldehyde stress in terms of plant Indole-3-acetic acid (IAA), ethylene, reactive oxygen species (ROS) levels and pollutant removal efficiency. Euphorbia milii was inoculated with native plant growth-promoting (PGP) endophytic and epiphytic isolates individually to investigate plant-endophyte compared to plant-epiphyte interactions under continuous formaldehyde fumigation. Under airborne formaldehyde stress, endophyte interacts with its host plant closely and provides higher levels of IAA which protected the plant against formaldehyde phytotoxicity by lowering intracellular ROS, ethylene levels and maintaining shoot epiphytic community; hence, higher pollutant removal. However, plant-epiphyte interactions could not provide enough IAA to confer protection against formaldehyde stress; thus, increased ROS and ethylene levels, large decrease in shoot epiphytic population and lower pollutant removal although epiphyte contacts with airborne pollutant directly (has greater access to gaseous formaldehyde). Endophyte-inoculated plant synthesized more tryptophan as a signaling molecule for its associated bacteria to produce IAA compared to the epiphyte-inoculated one. Under stress, PGP endophyte interacts with its host closely; thus, better protection against stress and higher pollutant removal compared to epiphyte which has limited interactions with the host plant; hence, lower pollutant removal.


Assuntos
Poluentes Atmosféricos/toxicidade , Bactérias/metabolismo , Etilenos/metabolismo , Euphorbia/microbiologia , Formaldeído/toxicidade , Ácidos Indolacéticos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Clorofila/metabolismo , Contagem de Colônia Microbiana , Endófitos/efeitos dos fármacos , Endófitos/fisiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/microbiologia , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Transdução de Sinais/efeitos dos fármacos , Triptofano/metabolismo
14.
Plant Physiol Biochem ; 107: 326-336, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27362296

RESUMO

Phytoremediation could be a cost-effective, environmentally friendly approach for the treatment of indoor air. However, some drawbacks still dispute the expediency of phytotechnology. Our objectives were to investigate the competency of plant growth-promoting (PGP) endophytic Bacillus cereus ERBP (endophyte root blue pea), isolated from the root of Clitoria ternatea, to colonize and stabilize within Zamioculcas zamiifolia and Euphorbia milii as non-native hosts without causing any disease or stress symptoms. Moreover, the impact of B. cereus ERBP on the natural shoot endophytic community and for the airborne formaldehyde removal capability of non-native hosts was assessed. Non-native Z. zamiifolia was effectively inoculated with B. cereus ERBP through soil as the most efficient method of endophyte inoculation. Denaturing gradient gel electrophoresis profiling of the shoot endophytic community verified the colonization and stability of B. cereus ERBP within its non-native host during a 20-d fumigation period without interfering with the natural shoot endophytic diversity of Z. zamiifolia. B. cereus ERBP conferred full protection to its non-native host against formaldehyde phytotoxicity and enhanced airborne formaldehyde removal of Z. zamiifolia whereas non-inoculated plants suffered from formaldehyde phytotoxicity because their natural shoot endophytic community was detrimentally affected by formaldehyde. In contrast, B. cereus ERBP inoculation into non-native E. milii deteriorated airborne formaldehyde removal of the non-native host (compared to a non-inoculated one) as B. cereus ERBP interfered with natural shoot endophytic community of E. milii, which caused stress symptoms and stimulated ethylene biosynthesis. Non-native host inoculation with PGP B. cereus ERBP could bear potentials and challenges for airborne formaldehyde removal.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Araceae/microbiologia , Bacillus cereus/fisiologia , Endófitos/fisiologia , Euphorbia/microbiologia , Formaldeído/isolamento & purificação , Araceae/efeitos dos fármacos , Araceae/genética , Bacillus cereus/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Eletroforese em Gel de Gradiente Desnaturante , Endófitos/efeitos dos fármacos , Euphorbia/efeitos dos fármacos , Euphorbia/genética , Formaldeído/toxicidade , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , RNA Ribossômico 16S/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
15.
Environ Sci Pollut Res Int ; 23(2): 962-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25943511

RESUMO

Cadmium (Cd) contaminated in rice grains is a serious problem because most Asians consume rice on a daily basis. Rice grown in Cd-contaminated soil normally did not have high concentration of Cd. However, soil samples used in this study had high concentrations of Cd. The purpose of this study was to clearly see the effects of biochar and microorganism addition in rice growing in Cd-contaminated soil. The initial Cd concentration in Cd-contaminated soil used in this study was about 650 mg kg(-1). Cadmium concentration in rice plants grown in Cd-contaminated soil with the addition of 1% (w/w) different biochars such as sawdust fly ash (SDFA), bagasse fly ash (BGFA), and rice husk ash (RHA) was investigated. The results showed that SDFA was the best biochar in terms of reducing cadmium accumulation in rice grains when compared to BGFA and RHA under the same conditions. In addition, rice plants grown in Cd-contaminated soil with the addition of various nonpathogenic microorganisms, such as Pseudomonas aeruginosa, Bacillus subtilis, and Beauveria bassiana were also studied. The results showed that the addition of 2% (v/v) microorganisms can reduce Cd accumulation in grains. It was found that grains obtained from Cd-contaminated soil with the addition of P. aeruginosa had the lowest cadmium concentration compared to the ones from soil amended with other strains. This was due to the fact that P. aeruginosa adsorbed more Cd itself into its cells than other strains. The rice plants grown in Cd-contaminated soil with the addition of biochars and microorganisms were also compared. The results showed that adding 2% (v/v) microorganisms seemed to reduce Cd accumulation in rice grains better than adding 1% (w/w) biochars. In addition, the amounts of calcium and magnesium in rice grains and the dry weight of plant in Cd-contaminated soil amended with P. aeruginosa were the highest in comparison to other microorganisms, biochars, and the soil without any amendments (Cd-soil control). It might be possible that microorganisms can cause leaching of Ca, Mg, etc. from contaminated soil and compete with Cd to be uptaken by plants. This would cause the increase in plant dry weight and higher mineral nutrients accumulation in grains. Both biochars and microorganisms are suitable for reducing the amount of Cd in rice grains. The application should depend on farmers, biochars available in nearby areas, etc. Therefore, microorganisms and biochars can be used to solve the problem of cadmium contamination in rice grains.


Assuntos
Cádmio/metabolismo , Carvão Vegetal , Oryza/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Cinza de Carvão , Poluição Ambiental , Oryza/crescimento & desenvolvimento , Solo
16.
Int J Phytoremediation ; 17(1-6): 382-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25409252

RESUMO

Cadmium (Cd) and zinc (Zn) phytoavailability and their phytoextraction by Sedum plumbizincicola using different nitrogen fertilizers, nitrification inhibitor (dicyandiamide, DCD) and urease inhibitor (N-(n-Butyl) thiophosphoric triamide, NBPT) were investigated in pot experiments where the soil was contaminated with 0.99 mg kg(-1) of Cd and 241 mg kg(-1) Zn. The soil solution pH varied between 7.30 and 8.25 during plant growth which was little affected by the type of N fertilizer. The (NH4)2SO4+DCD treatment produced higher NH4+-N concentrations in soil solution than the (NH4)2SO4 and NaNO3 treatment which indicated that DCD addition inhibited the nitrification process. Shoot Cd and Zn concentrations across all treatments showed ranges of 52.9-88.3 and 2691-4276 mg kg(-1), respectively. The (NH4)2SO4+DCD treatment produced slightly higher but not significant Cd and Zn concentrations in the xylem sap than the NaNO3 treatment. Plant shoots grown with NaNO3 had higher Cd concentrations than (NH4)2SO4+DCD treatment at 24.0 and 15.4 mg kg(-1), respectively. N fertilizer application had no significant effect on shoot dry biomass. Total Cd uptake in the urea+DCD treatment was higher than in the control, urea+NBPT, urea+NBPT+DCD, or urea treatments, by about 17.5, 23.3, 10.7, and 25.1%, respectively.


Assuntos
Cádmio/metabolismo , Recuperação e Remediação Ambiental/métodos , Fertilizantes/análise , Nitrogênio/metabolismo , Proteínas de Plantas/antagonistas & inibidores , Sedum/metabolismo , Poluentes do Solo/metabolismo , Urease/antagonistas & inibidores , Zinco/metabolismo , Biodegradação Ambiental , Recuperação e Remediação Ambiental/instrumentação , Nitrificação , Proteínas de Plantas/metabolismo , Sedum/enzimologia , Poluentes do Solo/análise , Urease/metabolismo
17.
Chemosphere ; 81(9): 1069-74, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20943250

RESUMO

Ethylene glycol (EG) is a group of dihydroxy alcohol that has been utilised in a variety of industrial and residential settings. EG contaminated wastewater has a high chemical oxygen demand (COD), which causes environmental problems. The aim of this research was to investigate the efficiency of the burhead plant (Echinodorus cordifolius (L.)) in the removal of mono-, di- and triethylene glycol (MEG, DEG and TEG), the first three members of the dihydroxy alcohol group, from synthetic wastewaters, to examine the toxic effect of EG on the plant and to identify differences among MEG, DEG, and TEG removal. It was found that the COD of synthetic wastewaters decreased to levels below the standard effluent (COD=120 mg L⁻¹) on day 18, 21 and 33 for MEG, DEG and TEG, respectively. On day 18 of the experiment, the burhead plant removed approximately 2000, 1950 and 730 mg L⁻¹ of MEG, DEG and TEG, respectively. The removal rate of MEG was faster than that of DEG and TEG, suggesting that the molecular size of the EG had affected its rate of removal. The concentrations of MEG, DEG, and TEG in plant tissue were measured to show that burhead can take up EG, and the major site of EG accumulation is the leaf. The molar of MEG that was taken up into the plant leaf was higher than that of DEG and TEG. This suggested that EG of smaller molecular sizes can be taken up more rapidly by the plant than EG of larger molecular sizes. EG concentrations in the leaf increased to a peak concentration and then slowly decreased. GC-MS analysis of DEG-treated plant tissue found MEG, 1,4-dioxan-2-one, neophytadiene, and 2-propenamide, that may be DEG-degradation products and/or compounds that are induced when plants are exposed to DEG. The result indicates that burhead can potentially be used for EG removal.


Assuntos
Alismataceae/metabolismo , Etilenoglicol/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Etilenoglicol/análise , Etilenoglicol/química , Etilenoglicóis/química , Etilenoglicóis/metabolismo , Peso Molecular , Folhas de Planta/efeitos dos fármacos , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA