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1.
Chem Biol Interact ; 333: 109310, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33212047

RESUMO

We wish to present a simple, rapid, cost-effective and environmentally safe method for staining proteins in polyacrylamide gels, using aqueous-based natural extracts from fresh green walnut (Juglans regia) hulls/husks. The technique takes not more than 10 min for staining and is comparable in sensitivity to the most commonly used Coomassie R-250 staining method when applied to different concentrations of Bovine Serum Albumin (BSA) and various amounts of E. coli extracts. The protein (BSA) band (~0.5 µg) and E. coli extract comprising ~25 µg total protein can be visualized on polyacrylamide gels. Compared to both Coomassie and Ponceau S staining, the current method displayed more intense bands when proteins are transferred to polyvinylidene fluoride (PVDF) membrane. Although the walnut-dye (WD) method does not require a time-consuming destaining step, excess background stain can simply be removed by washing in water. Extract from old dried black husks and extract from fresh green husks kept for a year was also effective. Using LC-MS, Myricetin and/or Kaempferol were found to be active compounds responsible for staining proteins. Compared to traditional Coomassie method, the inclusion of expensive and toxic solvents (methanol and acetic acid) is completely avoided resulting in positive health, environmental and economic benefits. In view of all these advantages, the WD method has immense potential to replace currently used protein staining techniques.


Assuntos
Química Verde/economia , Química Verde/métodos , Juglans/química , Extratos Vegetais/química , Proteínas/química , Coloração e Rotulagem/economia , Coloração e Rotulagem/métodos , Resinas Acrílicas/química , Géis
2.
N Biotechnol ; 60: 138-145, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33049406

RESUMO

There has been significant national interest and movement towards bioeconomic policy over the past decade. Through an examination of the current bioeconomic pathways in New Zealand, this paper outlines key barriers that transition pathways will need to overcome and factors needing development within the country's bioeconomic environment. New Zealand's strength in primary production, coupled with a market-led economy and recent green growth with low carbon policies, provide an excellent platform for bioeconomic development. However, the strength in established biological industries and lack of clearly defined vision or cohesive support for bioeconomic development provide sufficient inertia to realising the full potential. For a bioeconomy in New Zealand to flourish, a primary sector model that is cohesive and more integrated is needed to develop new niche industries and attract finance, while providing an overarching governance system to the primary industries.


Assuntos
Biotecnologia/economia , Química Verde/economia , Humanos , Nova Zelândia
3.
PLoS One ; 15(10): e0241400, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33125413

RESUMO

In view of the difficulty, high cost and complex technology of pharmaceutical logistics green transformation, based on the idea of green supply chain, three different government subsidy strategies for green logistics were proposed. Firstly, by constructing a Stackelberg game model with pharmaceutical logistics provider as the leader and manufacturer as the followers, the behavior selection and optimal decisions of the participants under the anarchic subsidy strategy, the single subsidy strategy of the pharmaceutical logistics provider, the single subsidy strategy of the pharmaceutical manufacturer and the coordinated subsidy strategy are analyzed respectively. Furthermore, the effects of different subsidy strategies on the green investment and strategy selection of logistics provider and manufacturer are compared. Finally, according to the research results, the paper provides reference and suggestions for the formulation of government subsidy strategy. The results show that the three subsidy strategies have different degrees of incentive effect on the green transformation of pharmaceutical logistics, and the single logistics provider subsidy strategy is the best.


Assuntos
Conservação dos Recursos Naturais , Indústria Farmacêutica , Algoritmos , Simulação por Computador , Conservação dos Recursos Naturais/economia , Tomada de Decisões , Indústria Farmacêutica/economia , Financiamento Governamental , Química Verde/economia , Humanos , Preparações Farmacêuticas/economia , Pesquisa
4.
Mater Sci Eng C Mater Biol Appl ; 111: 110790, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279790

RESUMO

MXene phases are a member of the intriguing 2D material family, beyond graphene. They are good candidates for many applications, however, their potential toxicity is of crucial importance for future development. Herein, we present a simple, low-cost and fully green approach for controlling the potential cytotoxicity of 2D MXenes after delamination by harnessing the interactions that occur between the surface of MXene phases and natural biomacromolecule - collagen. We also demonstrate that the step-by-step adsorption and desorption of collagen from the surface of 2D MXenes is easily controlled using in situ zeta potential measurements coupled with dynamic light scattering (DLS) method. The obtained results demonstrated that the electrostatically driven unprecedented susceptibility of the MXenes' surfaces to collagen. Surface-modification reduces toxicity of MXenes in vitro i.e. adjust cells' viabilities as well as reduce their oxidative stress. This indicates enhanced biocompatibility of 2D Ti3C2 and Ti2C MXenes surface-modified with collagen, which is involved in many bio-interactions as important building blocks in the human body. The presented study opens new avenues for designing MXenes with defined surface properties and paves the way for their future successful management in nano-medicinal applications.


Assuntos
Custos e Análise de Custo , Química Verde/economia , Elementos de Transição/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular , Humanos
5.
Int J Hyg Environ Health ; 226: 113471, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32078924

RESUMO

There is an increasing trend of developing various low-cost biogenic sorbents for the efficient and economical removal of noxious metals . Curry leaf powder (CLP), a promising non-toxic biosorbent containing several bioactive compounds was prepared by the pulverization of the dried leaves for the effective removal of Lead (Pb) and Cadmium (Cd). Various batch sorption experiments were carried out under constant temperature (25 °C), different pH (4.5-10.5), initial concentrations (50-200 mg L-1), adsorbent dosages (0.10-0.40 g) and contact times (0-60 min) to understand the optimum experimental conditions and simultaneously evaluate the adsorption isotherms and removal kinetics of CLP. Adsorption equilibrium was established in less than an hour interval (50 min). The pseudo-equilibrium process was best described by the pseudo-second-order kinetic (R2 ≥ 0.99), Freundlich and Langmuir isotherm model (R2 ≥ 0.94). The removal rate of Pb and Cd gradually increased (15.7 and 12.7 mg g-1 for Pb and Cd) at 100 mg L-1 of initial concentration till 60 min of contact period in a single contaminant system, the effect was non-significant for multiple adsorbent dosage systems (p > 0.05; t-test) though. The regeneration potential of the exhausted biosorbent was excellent upto 5 cycles with the better efficiency observed for Pb. The obtained results explicitly validated the probable utilization of CLP as a promising green adsorbent for metal removal . Future study may highlight the decontamination aspects of emerging contaminants with such green bio sorbents in large scale as well as mimicing the stomach conditions.


Assuntos
Cádmio/química , Chumbo/química , Murraya , Preparações de Plantas/química , Polifenóis/química , Pós/química , Poluentes Químicos da Água/química , Adsorção , Análise Custo-Benefício , Química Verde/economia , Cinética , Folhas de Planta , Reciclagem , Purificação da Água/economia , Purificação da Água/métodos
6.
Nanomedicine (Lond) ; 14(17): 2293-2313, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31414612

RESUMO

Aim: The primary goal of this work was to synthesize low-cost superparamagnetic iron oxide nanoparticles (SPIONs) with the aid of coconut water and evaluate the ability of macrophages to internalize them. Our motivation was to determine potential therapeutic applications in drug-delivery systems associated with magnetic hyperthermia. Materials & methods: We used the following characterization techniques: x-ray and electron diffractions, electron microscopy, spectrometry and magnetometry. Results: The synthesized SPIONs, roughly 4 nm in diameter, were internalized by macrophages, likely via endocytic/phagocytic pathways. They were randomly distributed throughout the cytoplasm and mainly located in membrane-bound compartments. Conclusion: Nanoparticles presented an elevated intrinsic loss power value and were not cytotoxic to mammalian cells. Thus, we suggest that low-cost SPIONs have great therapeutic potential.


Assuntos
Compostos Férricos/uso terapêutico , Química Verde/métodos , Macrófagos/metabolismo , Nanopartículas de Magnetita/uso terapêutico , Animais , Sistemas de Liberação de Medicamentos , Compostos Férricos/farmacocinética , Química Verde/economia , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/análise , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Células RAW 264.7
7.
Microb Pathog ; 135: 103609, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31247255

RESUMO

This article reports the utilization of Malus domestica for the synthesis of silver nanoparticles (AgNPs) with cytotoxic activity against the Michigan Cancer Foundation-7 (MCF-7) cell line as well as their antibacterial and radical scavenging potential. The biosynthesized AgNPs were confirmed using various analytical characterization techniques. The cytotoxic effect of Malus domestica-AgNPs (M.d-AgNPs) was studied by MTT assay and scavenging efficacy was assessed by DPPH, nitric oxide radical and phosphomolybdate assays. Furthermore, green synthesized nanoparticles were evaluated for their antibacterial activity against multidrug resistant-clinical isolates. M.d-AgNPs were observed to be almost spherical in shape with an average diameter from 50 to 107.3 nm as assessed by TEM and DLS. M.d-AgNPs revealed the dose-dependent antioxidant activity and antimicrobial activity against multidrug-resistant bacterial strain viz. Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli. Also, in vitro studies revealed dose-dependent cytotoxic effects of M.d-AgNPs treated MCF-7 cell line. The data strongly suggest that M.d-AgNPs had a potential antioxidant, antimicrobial and cytotoxicity activity.


Assuntos
Antibacterianos/biossíntese , Antibacterianos/farmacologia , Química Verde/métodos , Células MCF-7/efeitos dos fármacos , Malus/metabolismo , Nanopartículas Metálicas/química , Prata/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/análise , Biofilmes/efeitos dos fármacos , Análise Custo-Benefício , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Estabilidade de Medicamentos , Sequestradores de Radicais Livres , Química Verde/economia , Células HEK293/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Compostos Fitoquímicos/farmacologia , Difração de Raios X
8.
PLoS One ; 14(4): e0208643, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30990800

RESUMO

The production of concrete is one of the most significant contributors to global greenhouse gas emissions. This work focuses on bio-cementation-based products and their potential to reduce global warming potential (GWP). In particular, we address a proposed bio-cementation method employing bacterial metabolism in a two-step process of limestone dissolution and recrystallisation (BioZEment). A scenario-based techno-economic analysis (TEA) is combined with a life cycle assessment (LCA), a market model and a literature review of consumers' willingness to pay, to compute the expected reduction of global GWP. Based on the LCA, the GWP of 1 ton of BioZEment is found to be 70-83% lower than conventional concrete. In the TEA, three scenarios are investigated: brick, precast and onsite production. The results indicate that brick production may be the easiest way to implement the products, but that due to high cost, the impact on global GWP will be marginal. For precast production the expected 10% higher material cost of BioZEment only produces a marginal increase in total cost. Thus, precast production has the potential to reduce global GWP from concrete production by 0-20%. Significant technological hurdles remain before BioZEment-based products can be used in onsite construction scenarios, but in this scenario, the potential GWP reduction ranges from 1 to 26%. While the potential to reduce global GWP is substantial, significant efforts need to be made both in regard to public acceptance and production methods for this potential to be unlocked.


Assuntos
Bactérias/metabolismo , Dióxido de Carbono/metabolismo , Indústria da Construção , Materiais de Construção , Aquecimento Global , Carbonato de Cálcio/química , Carbonato de Cálcio/economia , Indústria da Construção/economia , Indústria da Construção/métodos , Materiais de Construção/análise , Materiais de Construção/economia , Materiais de Construção/microbiologia , Cristalização , Química Verde/economia , Química Verde/métodos , Efeito Estufa , Microbiologia Industrial/economia , Microbiologia Industrial/métodos , Solubilidade
9.
PLoS One ; 13(12): e0207755, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30532218

RESUMO

The present study underlines a statistically optimized, low cost, effective approach for efficient co-valorization of two non-efficiently utilized, highly accumulated, raw agro-industrial wastes: corn cob and glycerol for co-production of natural biopigments: monascus orange and red pigments by the aid of Monascus purpureus strain ATCC 16436. A three step sequential, statistical modeling approach: one variable at a time (OVAT), Plackett-Burman design (PBD), and central composite design (CCD) was employed to optimize the production of monascus pigments using co-solid state fermentation of the two raw agro-industrial wastes. Corn cob among other carbon sources (e.g., rice grains, sugarcane bagasse, and potato peel) was the most appropriate substrate triggering co-production of orange and red monascus pigments; deduced from OVAT. Glycerol and inoculum size proved to impose significant consequences (P<0.05) on the production of monascus pigments as inferred from PBD. The optimal levels of inoculum size (12 x 1011 spores/mL) and glycerol (2.17 M) did achieve a maximal color value of 133.77 and 108.02 color value units/mL of orange and red pigments, respectively at 30 oC after 10 days; concluded from CCD with an agitation speed of 150 rpm. Present data would underpin the large scale production of monascus pigments using the present approach for efficient exploitation of such biopigments in food, pharmaceutical and textile industries.


Assuntos
Glicerol/metabolismo , Química Verde/métodos , Monascus/metabolismo , Pigmentos Biológicos/biossíntese , Zea mays/metabolismo , Celulose/metabolismo , Cor , Análise Custo-Benefício , Fermentação , Química Verde/economia , Humanos , Resíduos Industriais/análise , Modelos Biológicos , Oryza/metabolismo , Pigmentos Biológicos/química , Saccharum/metabolismo , Solanum tuberosum/metabolismo
10.
Mar Drugs ; 16(9)2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30208611

RESUMO

The nutraceutical potential of microalgae boomed with the exploitation of new species and sustainable extraction systems of bioactive compounds. Thus, a laboratory-made continuous pressurized solvent extraction system (CPSE) was built to optimize the extraction of antioxidant compounds, such as carotenoids and PUFA, from a scarcely studied prokaryotic microalga, Gloeothece sp. Following "green chemical principles" and using a GRAS solvent (ethanol), biomass amount, solvent flow-rate/pressure, temperature and solvent volume-including solvent recirculation-were sequentially optimized, with the carotenoids and PUFA content and antioxidant capacity being the objective functions. Gloeothece sp. bioactive compounds were best extracted at 60 °C and 180 bar. Recirculation of solvent in several cycles (C) led to an 11-fold extraction increase of ß-carotene (3C) and 7.4-fold extraction of C18:2 n6 t (5C) when compared to operation in open systems. To fully validate results CPSE, this system was compared to a conventional extraction method, ultrasound assisted extraction (UAE). CPSE proved superior in extraction yield, increasing total carotenoids extraction up 3-fold and total PUFA extraction by ca. 1.5-fold, with particular extraction increase of 18:3 n3 by 9.6-fold. Thus, CPSE proved to be an efficient and greener extraction method to obtain bioactive extract from Gloeothece sp. for nutraceutical purposes-with low levels of resources spent, while lowering costs of production and environmental impacts.


Assuntos
Carotenoides/isolamento & purificação , Cianobactérias/química , Suplementos Nutricionais , Ácidos Graxos/isolamento & purificação , Química Verde/métodos , Microalgas/química , Antioxidantes/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Biomassa , Etanol/química , Química Verde/economia , Extração Líquido-Líquido/economia , Extração Líquido-Líquido/métodos , Temperatura , Ondas Ultrassônicas
11.
J Pharm Biomed Anal ; 158: 405-415, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29940496

RESUMO

This review describes briefly the high rate of counterfeiting of antimicrobial drugs with focus upon its immediate health consequences. The major part of this review encompasses accounts of the improvements achieved in the domain of miniaturization of capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D). The application of this principle into the development of portable devices as well as its application to counter the health-system-crippling phenomenon of counterfeit antibiotic formulations, are discussed in the context of developing countries.


Assuntos
Antibacterianos/análise , Medicamentos Falsificados/análise , Fraude/prevenção & controle , Química Verde/métodos , Microquímica/métodos , Países em Desenvolvimento/economia , Condutividade Elétrica , Eletroforese Capilar/economia , Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Eletroforese Capilar/tendências , Fraude/economia , Química Verde/economia , Química Verde/instrumentação , Química Verde/tendências , Microquímica/economia , Microquímica/instrumentação , Microquímica/tendências , Sensibilidade e Especificidade
12.
J Pharm Biomed Anal ; 158: 137-143, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29879543

RESUMO

Sideritis montana L. endemic of Turkey was screened for its polyphenols content and antioxidant activity. Factor analysis and experimental design have been applied to understand the structure of the separation process, to determine the effective parameters, and to accomplish the performance improvement. Face-centred composite design (FCD) of response surface methodology (RSM) was applied to evaluate the influences of solvent concentration, solvent amount, extraction time, and stirring speed of homogenizer-assisted extraction (HAE) as well as to model and to optimize the HAE. Quadratic models were highly significant (p < 0.0001) for the responses studied with high coefficients of determination (R2) of 0.9440, 0.9415 and 0.9521. The result of the study suggests that 15.02 mL of 22.69% EtOH solution (v/v), 70.16 s, and 9524.52 rpm of mixing speed are the optimal conditions to obtain the highest yield of total polyphenols (TPC) and flavonoids (TFC), and the best antioxidant activity (AA). Rosmarinic acid was identified as the most abundant component.


Assuntos
Antioxidantes/isolamento & purificação , Fracionamento Químico/métodos , Extratos Vegetais/isolamento & purificação , Polifenóis/isolamento & purificação , Sideritis/química , Antioxidantes/farmacologia , Fracionamento Químico/instrumentação , Cinamatos/isolamento & purificação , Cinamatos/farmacologia , Depsídeos/isolamento & purificação , Depsídeos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Química Verde/economia , Química Verde/instrumentação , Química Verde/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Solventes/química , Ácido Rosmarínico
13.
J Ind Microbiol Biotechnol ; 45(6): 405-415, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29749580

RESUMO

Deficiency in petroleum resources and increasing environmental concerns have pushed a bio-based economy to be built, employing a highly reproducible, metal contaminant free, sustainable and green biomanufacturing method. Here, a chiral drug intermediate L-pipecolic acid has been synthesized from biomass-derived lysine. This artificial bioconversion system involves the coexpression of four functional genes, which encode L-lysine α-oxidase from Scomber japonicus, glucose dehydrogenase from Bacillus subtilis, Δ1-piperideine-2-carboxylase reductase from Pseudomonas putida, and lysine permease from Escherichia coli. Besides, a lysine degradation enzyme has been knocked out to strengthen the process in this microbe. The overexpression of LysP improved the L-pipecolic acid titer about 1.6-folds compared to the control. This engineered microbial factory showed the highest L-pipecolic acid production of 46.7 g/L reported to date and a higher productivity of 2.41 g/L h and a yield of 0.89 g/g. This biotechnological L-pipecolic acid production is a simple, economic, and green technology to replace the presently used chemical synthesis.


Assuntos
Biomassa , Química Farmacêutica/métodos , Escherichia coli/metabolismo , Microbiologia Industrial/métodos , Lisina/química , Engenharia Metabólica/métodos , Ácidos Pipecólicos/química , Aminoácido Oxirredutases/química , Bacillus subtilis/genética , Química Farmacêutica/economia , Escherichia coli/genética , Fermentação , Glucose 1-Desidrogenase/genética , Química Verde/economia , Química Verde/métodos , Microbiologia Industrial/economia , Engenharia Metabólica/economia , Plasmídeos/genética , Pseudomonas putida/genética , Estereoisomerismo
14.
Appl Biochem Biotechnol ; 186(3): 507-524, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29658061

RESUMO

In this study, it was found that the residual stream from pretreatments of rice straw exhibited high antioxidant activity. Assays based on the Folin-Ciocalteu colorimetric method confirmed that the residual stream contained large amounts of phenolic compounds. Three antioxidant assays were employed to evaluate the bioactivity of the residual stream. Strong linear correlations existed among the release of phenolic compounds, saccharification efficiency, and antioxidant activity. The alkaline pretreatment provided a much greater release of phenolic compounds, especially phenolic acids, compared to the acid pretreatment, and consequently, it had stronger linear correlations than the acid pretreatment. Antibacterial experiments demonstrated the ability of the phenolic compounds in the residual stream to inhibit the growth of microorganisms, indicating the potential of these compounds as antimicrobial agents. To discuss the possibility of the co-production of antimicrobial agents and biofuels/biochemicals, both acid and alkaline pretreatments were optimized using response surface methodology. Under the optimal conditions, 285.7 g glucose could be produced from 1 kg rice straw with the co-production of 3.84 g FA and 6.98 g p-CA after alkaline pretreatment. These results show that the recovery of phenolic compounds from the residual stream could be a green strategy for the low-cost bioconversion of rice straw.


Assuntos
Antioxidantes/análise , Custos e Análise de Custo , Química Verde/economia , Oryza/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Testes de Sensibilidade Microbiana , Fenóis/análise
15.
Comb Chem High Throughput Screen ; 21(4): 254-261, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29542410

RESUMO

AIM AND OBJECTIVE: The present method is simple, green and highly efficient for the synthesis of 2-amino-4H-pyran derivatives which are achieved by a one pot three component cyclocondensation of aldehyde, malanonitrile and ethyl acetoacetate or methyl acetoacetate using DABCO under solvent free with grinding conditions at room temperature. MATERIAL AND METHODS: Some of the synthesized compounds were screened for their antimicrobial and antifungal activity. The study shows that these compounds show good antimicrobial activity. Furthermore, eight of the synthesized compounds were selected for screening of their anticancer activity against human astrocytoma-glioblastoma cell line (U373MG). Some of the compounds show good anticancer activity. RESULT: Grinding synthesis of 2-amino-4H-pyran derivatives catalyzed by DABCO with various aromatic aldehydes under solvent-free conditions at room temperature was examined. The obtained compounds (22 entries) were well synthesized in good to excellent yields. CONCLUSION: The present method is simple, rapid, and most efficient green protocol for the synthesis of 2-amino-4H-pyran derivatives using highly inexpensive and easily available DABCO as an efficient catalyst under grinding and solvent free condition at room temperature.


Assuntos
Antibacterianos/síntese química , Antineoplásicos/síntese química , Piranos/síntese química , Animais , Antifúngicos/síntese química , Catálise , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Química Verde/economia , Química Verde/métodos , Humanos , Piranos/farmacologia
16.
J Biosci Bioeng ; 126(2): 226-234, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29580783

RESUMO

In this work, hydrogen (H2) was produced through the fermentation of Spirogyra sp. biomass by Clostridium butyricum DSM 10702. Macronutrient stress was applied to increase the carbohydrate content in Spirogyra, and a 36% (w/w) accumulation of carbohydrates was reached by nitrogen depletion. The use of wet microalga as fermentable substrate was compared with physically and chemically treated biomass for increased carbohydrate solubilisation. The combination of drying, bead beating and mild acid hydrolysis produced a saccharification yield of 90.3% (w/w). The H2 production from Spirogyra hydrolysate was 3.9 L H2 L-1, equivalent to 146.3 mL H2 g-1 microalga dry weight. The presence of protein (23.2 ± 0.3% w/w) and valuable pigments, such as astaxanthin (38.8% of the total pigment content), makes this microalga suitable to be used simultaneously in both food and feed applications. In a Spirogyra based biorefinery, the potential energy production and food-grade protein and pigments revenue per cubic meter of microalga culture per year was estimated on 7.4 MJ, US $412 and US $15, respectively, thereby contributing to the cost efficiency and sustainability of the whole bioconversion process.


Assuntos
Biomassa , Reatores Biológicos , Biotecnologia/métodos , Metabolismo dos Carboidratos/fisiologia , Fermentação , Hidrogênio/metabolismo , Spirogyra/metabolismo , Biodegradação Ambiental , Biocombustíveis , Reatores Biológicos/microbiologia , Biotecnologia/economia , Biotecnologia/normas , Carboidratos , Química Verde/economia , Química Verde/métodos , Química Verde/normas , Hidrólise , Microalgas/metabolismo , Modelos Teóricos , Nitrogênio/metabolismo
17.
J Fluoresc ; 28(2): 573-579, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29508118

RESUMO

Carbon quantum dots (CQDs) due to its high fluorescent output is evolving as novel sensing material and is considered as future building blocks for nano sensing devices. Hence, in this investigation we report microwave assisted preparation and multi sensing application of CQDs. The microwave derived CQDs are characterized by Dynamic Light Scattering (DLS) experiment and Fourier Infrared spectra (FTIR) to investigate the size distribution and chemical purity respectively. Fluorescent emission spectra recorded at varying pH shows varying fluorescence emission intensities. Further, emission spectra recorded at different temperatures shows that fluorescence emission of CQDs greatly depends on temperature. Therefore, we demonstrate the pH and temperature sensing characteristics of CQDs by fluorescence quenching behaviour. In addition, the interaction and sensing behaviour of CQDs for dopamine is also presented in this work with a detection limit of 0.2 mM. The steady state and time-resolved methods have been employed in fluorescence quenching methods for sensing dopamine through CQDs at room temperature. The bimolecular quenching rate constants for different concentration have been measured. The interaction between CQDs and dopamine indicates fluorescence quenching method is an elegant process for detecting dopamine through CQDs.


Assuntos
Carbono/química , Análise Custo-Benefício , Dopamina/análise , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Pontos Quânticos/química , Dopamina/química , Química Verde/economia , Concentração de Íons de Hidrogênio , Limite de Detecção , Temperatura
18.
J Am Chem Soc ; 140(10): 3736-3742, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29451789

RESUMO

Many technologically relevant semiconductors contain toxic, heavily regulated (Cd, Pb, As), or relatively scarce (Li, In) elements and often require high manufacturing costs. We report a facile, general, low-temperature, and size tunable (4-28 nm) solution phase synthesis of ternary APnE2 semiconductors based on Earth-abundant and biocompatible elements (A = Na, Pn = Bi, E = S or Se). The observed experimental band gaps (1.20-1.45 eV) fall within the ideal range for solar cells. Computational investigation of the lowest energy superstructures that result from "coloring", caused by mixed cation sites present in their rock salt lattice, agrees with other better-known members of this family of materials. Our synthesis unlocks a new class of low cost and environmentally friendly ternary semiconductors that show properties of interest for applications in energy conversion.


Assuntos
Bismuto/química , Selênio/química , Semicondutores , Sódio/química , Enxofre/química , Química Verde/economia , Química Verde/métodos , Modelos Moleculares , Energia Solar , Propriedades de Superfície
19.
Angew Chem Int Ed Engl ; 57(35): 11116-11128, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-29460380

RESUMO

The scarcity of precious metals has led to the development of sustainable strategies for metal-catalyzed cross-coupling reactions. The establishment of new catalytic methods using iron is attractive owing to the low cost, abundance, ready availability, and very low toxicity of iron. In the last few years, sustainable methods for iron-catalyzed cross-couplings have entered the critical area of pharmaceutical research. Most notably, iron is one of the very few metals that have been successfully field-tested as highly effective base-metal catalysts in practical, kilogram-scale industrial cross-couplings. In this Minireview, we critically discuss the strategic benefits of using iron catalysts as green and sustainable alternatives to precious metals in cross-coupling applications for the synthesis of pharmaceuticals. The Minireview provides an essential introduction to the fundamental aspects of practical iron catalysis, highlights areas for improvement, and identifies new fields to be explored.


Assuntos
Técnicas de Química Sintética/métodos , Ferro/química , Preparações Farmacêuticas/síntese química , Catálise , Técnicas de Química Sintética/economia , Química Verde/economia , Química Verde/métodos , Preparações Farmacêuticas/química
20.
J Pharm Biomed Anal ; 151: 331-338, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29413982

RESUMO

A rapid, green, low cost and nondestructive attenuated total reflection near infrared (ATR NIR) method was developed to quantify the total polysaccharide and the main monosaccharides mannose and glucose in Dendrobium huoshanense. Total 100 D. huoshanense samples from different places were analyzed using ATR NIR method. Potential outlying samples were initially removed from the collected NIR data using the PCA-Mahalanobis distance method. Spectral data preprocessing was studied in the construction of a partial least squares (PLS) model and six different signal pretreatment methods, including multiplicative scattering correction (MSC), standard normal transformation (SNV), first and second derivatives, the combination of MSC with the first derivative, and the combination of SNV with the first derivative, were compared. The results showed that the best signal pretreatment method was the spectral data pretreated by SNV combined with the first derivative due to it showed the lowest root-mean-square error of cross-validation (RMSECV), highest R2 for both the polysaccharide and its main monosaccharides. In order to improve the performance of the model, the pretreated full spectrum was calculated by different wavelength selection method. The results showed that the optional wavelength selection model was the one simultaneously selecting the NIR wavelength ranges 7500-5750 cm-1, 5250-4700 cm-1, 4450-4300 cm-1 and 4200-4100 cm-1 because of the lowest RMSECV and the highest R2 among the ten wavelength selection models. The external validation and the complete external validation confirmed the robustness and reliability of the developed NIR model. The contents of the total polysaccharide and the main monosaccharides are the essential quality assessment criterion for plant medicines while their traditional quantification methods involved sample destruction, tedious sample processing and non-environmentally friendly pretreatment, therefore, our study might provide an efficient technique tool for the rapid, green and nondestructive quantification of the total polysaccharide and the main monosaccharides for D. huoshanense and other rich-in-polysaccharide plant medicines.


Assuntos
Dendrobium/química , Química Verde/métodos , Monossacarídeos/análise , Polissacarídeos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Algoritmos , Química Verde/economia , Química Verde/instrumentação , Análise dos Mínimos Quadrados , Modelos Químicos , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/economia , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Fatores de Tempo
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