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1.
Biol Aujourdhui ; 218(1-2): 55-61, 2024.
Artigo em Francês | MEDLINE | ID: mdl-39007777

RESUMO

The latest IPBES report clearly showed that pollution and proliferation of invasive alien species constituted two of the five major factors responsible for the biodiversity decline. Faced with this situation, we present here the development of nature-based solutions in response to these two challenges. This approach has firstly made it possible to progress in understanding the adaptation strategies of plants and associated micro-organisms to respond to attacks such as pollution. Thus, relevant studies showed that certain plant species are able to grow in environments contaminated with metallic elements, or even to sequester toxic pollutants in their leaves or their roots. This research has made it possible to provide original solutions for the ecological restoration of soils and the decontamination of aquatic systems using dead invasive exotic plant species. The promotion of these solutions through the concept of ecocatalysis, at the interface of ecology and chemistry, contributed to make them sustainable and economically viable.


Title: Protection de la biodiversité et sciences durables. Abstract: Le dernier rapport de l'IPBES a clairement montré que la pollution et la multiplication des espèces exotiques envahissantes constituaient deux des cinq facteurs majeurs responsables du déclin de la biodiversité. Face à cette situation, nous présentons dans cette brève revue le développement de solutions fondées sur la nature pour répondre à ces deux défis. Cette approche a tout d'abord permis de progresser dans la compréhension des stratégies d'adaptation des plantes et des microorganismes associés, pour répondre à des agressions telles que celle de la pollution. Ainsi, il a pu être démontré que certaines espèces végétales sont capables de se développer dans des milieux contaminés par des éléments métalliques, voire de séquestrer les polluants toxiques dans leurs feuilles ou leurs racines. Ces recherches ont permis d'apporter des solutions originales pour la restauration écologique des sols et la décontamination des systèmes aquatiques à l'aide d'espèces végétales exotiques envahissantes mortes. Afin de les rendre pérennes et économiquement viables, ces solutions ont été valorisées à travers le concept de l'écocatalyse, à l'interface de l'écologie et de la chimie.

2.
Chemosphere ; 313: 137307, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427577

RESUMO

Persistent and emerging organic pollutants represent a serious and global threat to human health and ecosystems. We describe here a simple, efficient and affordable technology for removing such organic pollutants from aquatic systems. Biosorption process was chosen, meeting these three criteria, and so that biosorbents should be biomass wastes combining the following characteristics: natural, cheap and abundant. Powdered dead roots from invasive alien species (Eichhornia crassipes, Pistia stratiotes and Fallopia japonica), and wastes rich in tannins such as coffee grounds and green tea grounds were tested as biosorbents for removing extensively used organic pollutants: organic UV-filters, insecticides and herbicides. The elemental composition and morphology of the biosorbents were fully determined. The biosorption kinetics for each pair of biosorbent/pollutant was described by a pseudo-second order model. Excellent biosorption efficiency was obtained for 10 µM solution of oxybenzone (89 ± 1%), octocrylene (90 ± 2%), lindane (88 ± 0%) and diuron (90 ± 1%) in only 2 h. And total removal of 10 µM of chlordecone (100 ± 0%) could be achieved, which could be of high concern for the population living in chlordecone-contaminated areas. As such pollutants can be found in aquatic ecosystems, an interference study with salts showed that biosorption efficiency remained as efficient in reconstituted seawater. A principal component analysis was performed as an attempt to rationalise the biosorption results. The solubility of the organic pollutants in water and the concentration of tanins in the biosorbents were key parameters.


Assuntos
Clordecona , Poluentes Ambientais , Poluentes Químicos da Água , Humanos , Biomassa , Ecossistema , Poluentes Químicos da Água/análise , Poluentes Ambientais/análise , Clordecona/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio
3.
Molecules ; 27(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35630556

RESUMO

A green and effective approach for the synthesis of structurally diversed α-hydroxyphosphonates via hydrophosphonylation of aldehydes under solventless conditions and promoted by biosourced catalysts, called ecocatalysts "Eco-MgZnOx" is presented. Ecocatalysts were prepared from Zn-hyperaccumulating plant species Arabidopsis halleri, with simple and benign thermal treatment of leaves rich in Zn, and without any further chemical treatment. The elemental composition and structure of Eco-MgZnOx were characterized by MP-AES, XRPD, HRTEM, and STEM-EDX techniques. These analyses revealed a natural richness in two unusual and valuable mixed zinc-magnesium and iron-magnesium oxides. The ecocatalysts were employed in this study to demonstrate their potential use in hydrophosphonylation of aldehydes, leading to various α-hydroxyphosphonate derivatives, which are critical building blocks in the modern chemical industry. Computational chemistry was performed to help discriminate the role of some of the constituents of the mixed oxide ecocatalysts. High conversions, broad substrate scope, mild reaction conditions, and easy purification of the final products together with simplicity of the preparation of the ecocatalysts are the major advantages of the presented protocol. Additionally, Eco-MgZnOx-P could be recovered and reused for up to five times.


Assuntos
Arabidopsis , Magnésio , Aldeídos/química , Catálise , Folhas de Planta , Zinco
4.
Molecules ; 27(10)2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35630783

RESUMO

The Michael addition reaction was revisited with a full focus on sustainability combined with efficiency, using mechanochemistry in mild conditions. First, the synthesis of cyclopentenone derivatives was chosen as a model reaction to find optimal conditions in mechanochemistry while using classical but weak bases. The reaction was efficient (84-95% yields), fast (2-6 h), solvent free, and required 0.1 equivalent of base. Aiming to reach greener conditions, classical bases were then replaced using new bio-sourced bases, called Eco-bases, that were easily prepared from plants and led to heterogeneous catalysts. The composition and structure of Eco-bases were characterized by MP-AES, XRPD, EBSD/EDS, HRTEM/EDX and ion chromatography. Interestingly, a high ratio of potassium was observed with the presence of K2Ca(CO3)2 for the most effective Eco-base. The new Eco-bases were used for the mechanical-assisted construction of functionalized alkenone derivatives. The versatility of the method has been successfully applied with good to excellent yields to different Michael donors and acceptors. Eco-bases were recycled and reused four times with the same performances. Combining Eco-bases and mechanochemistry in Michael addition reactions allowed reaching a maximum degree of sustainability (efficient, rapid, low catalyst loading, solvent-free reactions with bio-sourced catalysts) and participating in the development of mechanochemistry in sustainable chemistry.


Assuntos
Reciclagem , Catálise , Solventes
5.
Sci Rep ; 11(1): 23780, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893664

RESUMO

New Caledonian endemic Mn-hyperaccumulator Grevillea meisneri is useful species for the preparation of ecocatalysts, which contain Mn-Ca oxides that are very difficult to synthesize under laboratory conditions. Mechanisms leading to their formation in the ecocatalysts are unknown. Comparing tissue-level microdistribution of these two elements could provide clues. We studied tissue-level distribution of Mn, Ca, and other elements in different tissues of G. meisneri using micro-X-Ray Fluorescence-spectroscopy (µXRF), and the speciation of Mn by micro-X-ray Absorption Near Edge Structure (µXANES), comparing nursery-grown plants transplanted into the site, and similar-sized plants growing naturally on the site. Mirroring patterns in other Grevillea species, Mn concentrations were highest in leaf epidermal tissues, in cortex and vascular tissues of stems and primary roots, and in phloem and pericycle-endodermis of parent cluster roots. Strong positive Mn/Ca correlations were observed in every tissue of G. meisneri where Mn was the most concentrated. Mn foliar speciation confirmed what was already reported for G. exul, with strong evidence for carboxylate counter-ions. The co-localization of Ca and Mn in the same tissues of G. meisneri might in some way facilitate the formation of mixed Ca-Mn oxides upon preparation of Eco-CaMnOx ecocatalysts from this plant. Grevillea meisneri has been successfully used in rehabilitation of degraded mining sites in New Caledonia, and in supplying biomass for production of ecocatalysts. We showed that transplanted nursery-grown seedlings accumulate as much Mn as do spontaneous plants, and sequester Mn in the same tissues, demonstrating the feasibility of large-scale transplantation programs for generating Mn-rich biomass.


Assuntos
Manganês/metabolismo , Proteaceae/metabolismo , Biodegradação Ambiental , Biotransformação , Poluição Ambiental , Metais Pesados/metabolismo , Nova Caledônia , Especificidade de Órgãos , Proteaceae/citologia , Poluentes do Solo
6.
Molecules ; 26(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34885776

RESUMO

Cyclic oxyterpenes are natural products that are mostly used as fragrances, flavours and drugs by the cosmetic, food and pharmaceutical industries. However, only a few cyclic oxyterpenes are accessible via chemical syntheses, which are far from being ecofriendly. We report here the synthesis of six cyclic oxyterpenes derived from ß-pinene while respecting the principles of green and sustainable chemistry. Only natural or biosourced catalysts were used in mild conditions that were optimised for each synthesis. A new generation of ecocatalysts, derived from Mn-rich water lettuce, was prepared via green processes, characterised by MP-AES, XRPD and TEM analyses, and tested in catalysis. The epoxidation of ß-pinene led to the platform molecule, ß-pinene oxide, with a good yield, illustrating the efficacy of the new generation of ecocatalysts. The opening ß-pinene oxide was investigated in green conditions and led to new and regioselective syntheses of myrtenol, 7-hydroxy-α-terpineol and perillyl alcohol. Successive oxidations of perillyl alcohol could be performed using no hazardous oxidant and were controlled using the new generation of ecocatalysts generating perillaldehyde and cuminaldehyde.


Assuntos
Química Verde , Terpenos/síntese química , Benzaldeídos/síntese química , Benzaldeídos/química , Monoterpenos Bicíclicos/síntese química , Monoterpenos Bicíclicos/química , Catálise , Cimenos/síntese química , Cimenos/química , Elementos Químicos , Monoterpenos/síntese química , Monoterpenos/química , Análise de Componente Principal , Terpenos/química , Difração de Raios X
7.
RSC Adv ; 11(45): 28085-28091, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35480752

RESUMO

In parallel with increasing Ni production and utilisation, Ni pollution in the soil-water continuum has become an alarming and global problem. Solutions for removing Ni from industrial effluents have been widely investigated and biosorption has emerged as an efficient, cost-effective, scalable and sustainable alternative for water treatment. However, the biosorption capacity is limited by the chemical composition of the biomaterial and the Ni-enriched biomaterials are rarely valorised. In this work, the biosorption capacity of three abundant biomaterials with different chemical properties - water hyacinth, coffee grounds and pinecones - was studied before and after functionalization, and reached a maximum biosorption capacity of 51 mg g-1 of Ni(ii). A bioinspired functionalization approach was investigated introducing carboxylate moieties and was conducted in green conditions. The Ni-enriched biomaterials were valorised by transformation into catalysts, which were characterised by MP-AES and XRPD. Their characterisation revealed a structure similar to nickel formate, and hence the Eco-Ni(HCOO)2 catalysts were tested in Suzuki-Miyaura reactions. Several aryl iodides were successfully cross-coupled to phenylboronic acids using Eco-Ni(HCOO)2 without any ligand, a mild and green base in a mixture of green solvents.

8.
Chemistry ; 27(2): 809-814, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33037687

RESUMO

A new sustainable method is reported for the formation of aromatic carbon-heteroatom bonds under solvent-free and mild conditions (no co-oxidant, no strong acid and no toxic reagents) by using a new type of green ionic liquid. The bromination of methoxy arenes was chosen as a model reaction. The reaction methodology is based on only using natural sodium bromine, which is transformed into an electrophilic brominating reagent within an ionic liquid, easily prepared from the melted salt FeCl3 hexahydrate. Bromination reactions with this in-situ-generated reagent gave good yields and excellent regioselectivity under simple and environmentally friendly conditions. To understand the unusual bromine polarity reversal of sodium bromine without any strong oxidant, the molecular structure of the reaction medium was characterised by Raman and direct infusion electrospray ionisation mass spectroscopy (ESI-MS). An extensive computational investigation using density functional theory methods was performed to describe a mechanism that suggests indirect oxidation of Br- through new iron adducts. The versatility of the methodology was successively applied to nitration and thiocyanation of methoxy arenes using KNO3 and KSCN in melted hexahydrated FeCl3 .

9.
Sci Rep ; 9(1): 7326, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086238

RESUMO

Eichhornia crassipes is well known as an invasive aquatic plant. It is also used very effectively in phytoremediation, particularly for the rhizofiltration of effluents contaminated by heavy metals. In this article, we show that it is also an excellent bioindicator of water polluted by worrying organic pollutants such as endocrine disruptors and neonicotinoids. As a proof of concept, di-n-hexylphthalate, pentabromodiphenyl ether, nitenpyram, acetamiprid and bis (3-tert-butyl-4-hydroxy-6-methylphenyl) sulfide were clearly identified by UHPLC-HRMS or GC-MS in the root system of E. crassipes after a short period of exposure. These results open up new perspectives for the remediation of water polluted by alarming organic pollutants.


Assuntos
Eichhornia/química , Monitoramento Ambiental/métodos , Espécies Sentinelas/metabolismo , Poluentes Químicos da Água/análise , Poluição da Água/prevenção & controle , Biodegradação Ambiental , Eichhornia/metabolismo , Disruptores Endócrinos/análise , Disruptores Endócrinos/metabolismo , Neonicotinoides/análise , Neonicotinoides/metabolismo , Raízes de Plantas/química , Poluentes Químicos da Água/metabolismo
10.
Environ Sci Pollut Res Int ; 26(19): 19327-19334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073830

RESUMO

Based on the ability of some specific aquatic plants to concentrate metals in their roots, we propose an innovative biosorption system to clean up mining effluents. The system we propose represents an interesting solution to an important environmental problem, the decontamination of metal-polluted water and prevention of dispersal of metals into the environment. The solution presented is a form of ecological recycling of Zn, an essential primary metal in many industrial applications. Finally, the methodology developed is a sustainable way of managing the biomass from eradication or control of invasive plants.


Assuntos
Metais Pesados/análise , Mineração , Plantas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Biomassa , Filtração , Modelos Teóricos , Raízes de Plantas/química
11.
Front Chem ; 6: 48, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29637065

RESUMO

Zn hyperaccumulator (Arabidobsis halleri) and Zn accumulator Salix "Tordis" (Salix schwerinii × Salix viminalis) have shown their interest in the phytoextraction of polluted brownfields. Herein, we explore a novel methodology based on the chemical valorization of Zn-rich biomass produced by these metallophyte plants. The approach is based on the use of polymetallic salts derived from plants as bio-based catalysts in organic chemistry. The formed ecocatalysts were characterized via ICP-MS, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) in order to precise the chemical composition, structure, and behavior of the formed materials. The Doebner-Knoevenagel reaction was chosen as model reaction to study their synthetic potential. Significant differences to usual catalysts such as zinc (II) chloride are observed. They can principally be related to a mixture of unusual mineral species. DFT calculations were carried out on these salts in the context of the Gutmann theory. They allow the rationalization of experimental results. Finally, these new bio-based polymetallic catalysts illustrated the interest of this concept for green and sustainable catalysis.

12.
Chem Biodivers ; 14(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27981800

RESUMO

Plants from the Brassicaceae family are known to contain secondary metabolites called glucosinolates. Our goal was to establish by LC/MS the glucosinolate profile of seeds of three Brassicaceae species known to hyperaccumulate heavy metals. We investigated Alyssum fallacinum auct. non Hausskn., Iberis intermedia Guers., and Noccaea caerulescens (J. Presl & C. Presl) F. K. Mey. Our results indicate that A. fallacinum seeds contain glucoiberin and glucoibervirin, which had not been previously identified in this plant. Furthermore, we report for the first time the presence of glucoiberin, glucoibervirin, glucotropaeolin, and sinigrin in I. intermedia. We have detected for the first time glucoconringiin in N. caerulescens. In addition, glucosinalbin, 4-hydroxyglucobrassicin, and glucomoringin were also detected.


Assuntos
Brassicaceae/química , Glucosinolatos/análise , Brassicaceae/metabolismo , Cromatografia Líquida de Alta Pressão , Glucosinolatos/química , Isotiocianatos/análise , Extratos Vegetais/química , Sementes/química , Sementes/metabolismo , Espectrometria de Massas por Ionização por Electrospray
13.
Chemosphere ; 146: 75-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706934

RESUMO

The influence of Fe oxides, Mn oxides and organic matter (OM) on the Cu and Co mobility in soil and accumulation in the metallophyte Anisopappus chinensis (Ac), as compared with Helianthus annuus (Ha), was experimentally investigated. Growth and accumulation response when increasing the exchangeable Cu and Co concentrations in soil were also investigated. Plants were cultivated on soil where concentrations of Cu, Co, Fe oxides, Mn oxides and OM content were varied according to 36 treatments. The OM supply decreased the Cu mobility and increased the Co mobility, resulting in decreasing the foliar Cu of Ac and increasing the foliar Co of Ha. The Fe oxides supply could increase the Cu accumulation for Ac, but was not verified for Ha. Compared with Ha, Ac increasingly accumulated Cu and Co without negative effect on plant growth while increasing Cu and Co mobility to phytotoxic concentrations. The results revealed promising perspectives for the use of Ac in Cu-contaminated environment phytoremediation applications.


Assuntos
Asteraceae/metabolismo , Cobalto/metabolismo , Cobre/metabolismo , Óxidos/química , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Monitoramento Ambiental , Helianthus/metabolismo , Ferro/química , Magnésio/química , Compostos Orgânicos/química
14.
Int J Syst Evol Microbiol ; 65(Pt 5): 1525-1530, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25701848

RESUMO

A Gram-stain-negative, aerobic, rod-shaped, non-spore-forming bacterium (ChimEc512(T)) was isolated from 56 host seedlings of the hyperaccumulating Anthyllis vulneraria legume, which was on an old zinc mining site at Les Avinières, Saint-Laurent-Le-Minier, Gard, South of France. On the basis of 16S rRNA gene sequence similarities, strain ChimEc512(T) was shown to belong to the genus Rhizobium and to be most closely related to Rhizobium endophyticum CCGE 2052(T) (98.4%), Rhizobium tibeticum CCBAU 85039(T) (98.1%), Rhizobium grahamii CCGE 502(T) (98.0%) and Rhizobium mesoamericanum CCGE 501(T) (98.0%). The phylogenetic relationships of ChimEc512(T) were confirmed by sequencing and analyses of recA and atpD genes. DNA-DNA relatedness values of strain ChimEc512(T) with R. endophyticum CCGE 2052(T), R. tibeticum CCBAU 85039(T), R. mesoamericanum CCGE 52(T), Rhizobium grahamii CCGE 502(T), Rhizobium etli CCBAU 85039(T) and Rhizobium radiobacter KL09-16-8-2(T) were 27, 22, 16, 18, 19 and 11%, respectively. The DNA G+C content of strain ChimEc512(T) was 58.9 mol%. The major cellular fatty acid was C18 : 1ω7c, characteristic of the genus Rhizobium . The polar lipid profile included phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol and phosphatidylcholine and moderate amounts of aminolipids, phospholipid and sulfoquinovosyl diacylglycerol. Although ChimEc512(T) was able to nodulate A. vulneraria, the nodC and nifH genes were not detected by PCR. The rhizobial strain was tolerant to high concentrations of heavy metals: up to 35 mM Zn and up to 0.5 mM Cd and its growth kinetics was not impacted by Zn. The results of DNA-DNA hybridizations and physiological tests allowed genotypic and phenotypic differentiation of strain ChimEc512(T) from species of the genus Rhizobium with validly published names. Strain ChimEc512(T), therefore, represents a novel species, for which the name Rhizobium metallidurans sp. nov. is proposed, with the type strain ChimEc512(T) ( =DSM 26575 = CIP 110550(T)).


Assuntos
Fabaceae/microbiologia , Filogenia , Rhizobium/classificação , Simbiose , Zinco , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , França , Mineração , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhizobium/genética , Rhizobium/isolamento & purificação , Análise de Sequência de DNA
15.
Environ Sci Pollut Res Int ; 22(8): 5592-607, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25065482

RESUMO

New Caledonia is a widely recognised marine and terrestrial biodiversity hot spot. However, this unique environment is under increasing anthropogenic pressure. Major threats are related to land cover change and include fire, urban sprawling and mining. Resulting habitat loss and fragmentation end up in serious erosion of the local biodiversity. Mining is of particular concern due to its economic significance for the island. Open cast mines were exploited there since 1873, and scraping out soil to access ores wipes out flora. Resulting perturbations on water flows and dramatic soil erosion lead to metal-rich sediment transport downstream into rivers and the lagoon. Conflicting environmental and economic aspects of mining are discussed in this paper. However, mining practices are also improving, and where impacts are inescapable ecological restoration is now considered. Past and ongoing experiences in the restoration of New Caledonian terrestrial ecosystems are presented and discussed here. Economic use of the local floristic diversity could also promote conservation and restoration, while providing alternative incomes. In this regard, Ecocatalysis, an innovative approach to make use of metal hyperaccumulating plants, is of particular interest.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Meio Ambiente , Poluentes Ambientais/análise , Metais Pesados/análise , Mineração/métodos , Plantas/metabolismo , Biodegradação Ambiental , Metais Pesados/metabolismo , Nova Caledônia
16.
Environ Sci Pollut Res Int ; 22(8): 5686-98, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25226830

RESUMO

We propose for the first time using metal hyperaccumulating plants for the construction of a repertoire of protection and deprotection conditions in a concept of orthogonal sets. Protection of alcohol, carbonyl, carboxyl, and amino groups are considered. The ecocatalysts derived from metal-rich plants allow selective, mild, eco-friendly, and efficient protection or deprotection reactions. The selectivity is controlled by the choice of the metal, which is hyperaccumulated by the metallophyte.


Assuntos
Brassicaceae/metabolismo , Técnicas de Química Sintética/métodos , Química Verde/métodos , Plantago/metabolismo , Proteaceae/metabolismo , Zinco/farmacocinética , Acetilação , Álcoois/química , Dióxido de Carbono/química , Catálise , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Folhas de Planta/metabolismo , Zinco/metabolismo
17.
Environ Sci Pollut Res Int ; 22(8): 5653-66, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25172465

RESUMO

Phytoextraction is widely used for the reclamation of degraded sites, particularly to remove trace metals from contaminated soils. Whereas this technique demonstrates several advantages, the biomass resulting from phytoextraction processes is highly enriched in metallic elements and constitutes therefore a problematic waste. We show here that this biomass can be used for the preparation of novel polymetallic extracts, with high potential as catalysts or reagents in organic synthesis. This new concept of ecocatalysis constitutes an innovative recycling of metallic elements whose current known reserves could be exhausted in the coming decades. The ecocatalysts Eco-Zn and Eco-Ni prepared respectively from Zn and Ni hyperaccumulating plants display two distinct chemical reactivities, starting from the same substrates. Eco-Zn led to the formation of esters of commercial interest for the fragrance industry, following a hydro-acyloxy-addition reaction pathway. In contrast, Eco-Ni afforded chlorinated products thank to the hydrochlorination of alkenes. Both ecocatalysts allowed the synthesis of valuable products in high yields through methodologies in line with the spirit of sustainable chemistry.


Assuntos
Biodegradação Ambiental , Biodiversidade , Brassicaceae/metabolismo , Níquel/metabolismo , Plantas/metabolismo , Poluentes do Solo/metabolismo , Zinco/metabolismo , Catálise , Níquel/análise , Poluentes do Solo/análise , Zinco/análise
18.
Environ Sci Pollut Res Int ; 22(8): 5677-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25131683

RESUMO

A direct, general and efficient method to synthesize 2H-chromenes (2H-benzo[b]pyrans), identified as environmentally friendly pesticides, has been developed. This approach lays on the new concept of ecocatalysis, which involves the use of biomass from phytoextraction processes, as a valuable source of metallic elements for chemical synthesis. This methodology is similar or superior to known methods, affording 2H-chromenes with good to excellent yields (60-98%), including the preparation of precocene I, a natural insect growth regulator, with 91% yield. The approach is ideal for poor reactive substrates such as phenol or naphthol, classically transformed into 2H-chromenes by methodologies associated with environmental issues. These results illustrate the interest of combining phytoextraction and green synthesis of natural insecticides.


Assuntos
Biodegradação Ambiental , Poluentes Ambientais/farmacocinética , Química Verde/métodos , Inseticidas/síntese química , Magnoliopsida/metabolismo , Metais Pesados/farmacocinética , Controle de Pragas/métodos , Benzopiranos/química , Benzopiranos/metabolismo , Canabinoides/síntese química , Canabinoides/metabolismo , Catálise , Poluentes Ambientais/análise , Ácidos de Lewis/química , Ácidos de Lewis/metabolismo , Metais Pesados/análise , Estrutura Molecular
19.
Environ Sci Pollut Res Int ; 22(8): 5620-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25138558

RESUMO

Relationships between the trace-elements (TE) content of plants and associated soil have been widely investigated especially to understand the ecology of TE hyperaccumulating species to develop applications using TE phytoextraction. Many studies have focused on the possibility of quantifying the soil TE fraction available to plants, and used bioconcentration (BC) as a measure of the plants ability to absorb TE. However, BC only offers a static view of the dynamic phenomenon of TE accumulation. Accumulation kinetics are required to fully account for TE distributions in plants. They are also crucial to design applications where maximum TE concentrations in plant leaves are needed. This paper provides a review of studies of BC (i.e. soil-plant relationships) and leaf-age in relation to TE hyperaccumulation. The paper focuses of Ni and Mn accumulators and hyperaccumulators from New Caledonia who were previously overlooked until recent Ecocatalysis applications emerged for such species. Updated data on Mn hyperaccumulators and accumulators from New Caledonia are also presented and advocate further investigation of the hyperaccumulation of this element. Results show that leaf-age should be considered in the design of sample collection and allowed the reclassification of Grevillea meisneri known previously as a Mn accumulator to a Mn hyperaccumulator.


Assuntos
Manganês/farmacocinética , Níquel/farmacocinética , Folhas de Planta/metabolismo , Poluentes do Solo/farmacocinética , Solo/química , Biodegradação Ambiental , Manganês/análise , Modelos Biológicos , Nova Caledônia , Níquel/análise , Folhas de Planta/química , Poluentes do Solo/análise
20.
Environ Sci Pollut Res Int ; 22(8): 5633-52, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25263417

RESUMO

Among the phytotechnologies used for the reclamation of degraded mining sites, phytoextraction aims to diminish the concentration of polluting elements in contaminated soils. However, the biomass resulting from the phytoextraction processes (highly enriched in polluting elements) is too often considered as a problematic waste. The manganese-enriched biomass derived from native Mn-hyperaccumulating plants of New Caledonia was presented here as a valuable source of metallic elements of high interest in chemical catalysis. The preparation of the catalyst Eco-Mn1 and reagent Eco-Mn2 derived from Grevillea exul exul and Grevillea exul rubiginosa was investigated. Their unusual polymetallic compositions allowed to explore new reactivity of low oxidative state of manganese-Mn(II) for Eco-Mn1 and Mn(IV) for Eco-Mn2. Eco-Mn1 was used as a Lewis acid to catalyze the acetalization/elimination of aldehydes into enol ethers with high yields; a new green and stereoselective synthesis of (-)-isopulegol via the carbonyl-ene cyclization of (+)-citronellal was also performed with Eco-Mn1. Eco-Mn2 was used as a mild oxidative reagent and controlled the oxidation of aliphatic alcohols into aldehydes with quantitative yields. Oxidative cleavage was interestingly noticed when Eco-Mn2 was used in the presence of a polyol. Eco-Mn2 allowed direct oxidative iodination of ketones without using iodine, which is strongly discouraged by new environmental legislations. Finally, the combination of the properties in the Eco-Mn catalysts and reagents gave them an unprecedented potential to perform sequential tandem oxidation processes through new green syntheses of p-cymene from (-)-isopulegol and (+)-citronellal; and a new green synthesis of functionalized pyridines by in situ oxidation of 1,4-dihydropyridines.


Assuntos
Biodegradação Ambiental , Química Verde/métodos , Ácidos de Lewis/metabolismo , Magnoliopsida/metabolismo , Manganês/farmacocinética , Monoterpenos Acíclicos , Álcoois/metabolismo , Aldeídos/metabolismo , Catálise , Cimenos , Di-Hidropiridinas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Cetonas/metabolismo , Espectroscopia de Ressonância Magnética , Manganês/química , Monoterpenos/metabolismo , Nova Caledônia , Oxirredução
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