Enyzmed pretreated empty pabn fruit bunch for biofuel production

Lignin peroxidase (LiP) and manganese peroxidase (1.1nP) enzymes were used to pre-treat empty fruit bunch (EPFB) before pyrolysis. Statistical analysis indicated that at 71.6%, LiP demonstrated greater lignin degradation compared to 67.9% J\1nP. Interestingly, the pretreatment sample has resulted in higher bio-oil yield compared to the untreated sample. Both LiP-treated and MnP-treated EPFB yielded approximately 30 wt% of bio-oil compared to 20 wt% of yield for the untreated sample

Green biodiesel production: a review on feedstock, catalyst, monolithic reactor, and supercritical fluid technology

The advancement of alternative energy is primarily catalyzed by the negative environmental impacts and energy depletion caused by the excessive usage of fossil fuels. Biodiesel has emerged as a promising substitute to petrodiesel because it is biodegradable, less toxic, and reduces greenhouse gas emission. Apart from that, biodiesel can be used as blending component or direct replacements for diesel fuel in automotive engines. A diverse range of methods have been reported for the conversion of renewable feedstocks (vegetable oil or animal fat) into biodiesel with transesterification being the most preferred method. Nevertheless, the cost of producing biodiesel is higher compared to fossil fuel, thus impeding its commercialization potentials. The limited source of reliable feedstock and the underdeveloped biodiesel production route have prevented the full-scale commercialization of biodiesel in many parts of the world. In a recent development, a new technology that incorporates monoliths as support matrices for enzyme immobilization in supercritical carbon dioxide (SC-CO2) for continuous biodiesel production has been proposed to solve the problem. The potential of SC-CO2 system to be applied in enzymatic reactors is not well documented and hence the purpose of this review is to highlight the previous studies conducted as well as the future direction of this technology

Production polystyrene micro-emulsion as template for monolith synthesis

Monolith have received much attention as high-performance chromatographic matrices due to its convective mass transfer and interconnected porous structure. Biodegradable polymers, free radicals and cross-linkers are among the templates used to form pore structure. However, poor heat dissipation and uneven pore size distribution across monolith remain as a key challenge in monolith fabrication. Therefore, this study aims to synthesize and characterize polystyrene micro-emulsion as template for monolith. The operating conditions for the synthesis of the polymeric micro-emulsion, that includes polymer concentration (14 - 35 wt %), surfactant concentration (1 - 9 wt %), temperature (30 - 70oC) and stirring rate (500 - 1000 rpm), were designed using Response Surface Methodology (RSM). The characterizations of resulting particles were observed using Scanning Electron Microscopy (SEM) and Inverted Microscope. The sizes of the particles were determined within range of 5.9 - 11.7 µm. Out of the 30 tested samples with different operating conditions, observation under the inverted microscope indicated homogenous particles of polystyrene microemulsion while some forming aggregations. Sample that was synthesized using 21 wt% polymer, 3 wt% surfactant, stirring rate at 875 rpm and heated at 40 oC resulted homogenous particles with particle diameter ranging from 7.92 µm to 8.80 µm. Good particle homogeneity was also obtained at a higher polymer concentration (35 wt %) using similar surfactant concentration and operating temperature at slower stirring rate (625 rpm). Samples aggregation were observed when using 35 wt % polymer, 7 wt % surfactant heated at 50oC at 750 rpm as well as sample under parameter of 25 wt% polymer wt % surfactant for 60oC stirring at 875 rpm. The findings of the study provide useful insights on the feasibility of polymeric micro-emulsion particles as a directing template for monolith fabrication with structured pores

Interfacial biocatalytic performance of nanofiber-supported β-galactosidase for production of galacto-oligosaccharides

© 2020 by the authors. Molecular distribution, structural conformation and catalytic activity at the interface between enzyme and its immobilising support are vital in the enzymatic reactions for producing bioproducts. In this study, a nanobiocatalyst assembly, β-galactosidase immobilized on chemically modified electrospun polystyrene nanofibers (PSNF), was synthesized for converting lactose into galacto-oligosaccharides (GOS). Characterization results using scanning electron microscopy (SEM) and fluorescence analysis of fluorescein isothiocyanat (FITC) labelled β-galactosidase revealed homogenous enzyme immobilization, thin layer structural conformation and biochemical functionalities of the nanobiocatalyst assembly. The β-galactosidase/PSNF assembly displayed enhanced enzyme catalytic performance at a residence time of around 1 min in a disc-stacked column reactor. A GOS yield of 41% and a lactose conversion of 88% was achieved at the initial lactose concentration of 300 g/L at this residence time. This system provided a controllable contact time of products and substrates on the nanofiber surface and could be used for products which are sensitive to the duration of nanobiocatalysis.Universiti Malaysia Sabah; Malaysian Government; University of Adelaide

A Novel fry1 Allele Reveals the Existence of a Mutant Phenotype Unrelated to 5′->3′ Exoribonuclease (XRN) Activities in Arabidopsis thaliana Roots

BACKGROUND Mutations in the FRY1/SAL1 Arabidopsis locus are highly pleiotropic, affecting drought tolerance, leaf shape and root growth. FRY1 encodes a nucleotide phosphatase that in vitro has inositol polyphosphate 1-phosphatase and 3',(2'),5'-bisphosphate nucleotide phosphatase activities. It is not clear which activity mediates each of the diverse biological functions of FRY1 in planta. PRINCIPAL FINDINGS A fry1 mutant was identified in a genetic screen for Arabidopsis mutants deregulated in the expression of Pi High affinity Transporter 1;4 (PHT1;4). Histological analysis revealed that, in roots, FRY1 expression was restricted to the stele and meristems. The fry1 mutant displayed an altered root architecture phenotype and an increased drought tolerance. All of the phenotypes analyzed were complemented with the AHL gene encoding a protein that converts 3'-polyadenosine 5'-phosphate (PAP) into AMP and Pi. PAP is known to inhibit exoribonucleases (XRN) in vitro. Accordingly, an xrn triple mutant with mutations in all three XRNs shared the fry1 drought tolerance and root architecture phenotypes. Interestingly these two traits were also complemented by grafting, revealing that drought tolerance was primarily conferred by the rosette and that the root architecture can be complemented by long-distance regulation derived from leaves. By contrast, PHT1 expression was not altered in xrn mutants or in grafting experiments. Thus, PHT1 up-regulation probably resulted from a local depletion of Pi in the fry1 stele. This hypothesis is supported by the identification of other genes modulated by Pi deficiency in the stele, which are found induced in a fry1 background. CONCLUSIONS/SIGNIFICANCE Our results indicate that the 3',(2'),5'-bisphosphate nucleotide phosphatase activity of FRY1 is involved in long-distance as well as local regulatory activities in roots. The local up-regulation of PHT1 genes transcription in roots likely results from local depletion of Pi and is independent of the XRNs.This work was supported by an ANR-GENOPLANT grant (RIBOROOT-ANR06 GPLA 011) and the CEA agency. Array hybridizations have been partly supported by RNG (Réseau National des Génopoles, Evry, France). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. No additional external funding received for this study

Effect of Crosslinkers on Immobilization of ß-Galactosidase on Polymethacrylate Monolith.

Advances in biotechnology unfold a new frontier for the development of enzyme-catalysed bioprocess which is green and sustainable in contrast with chemical processes. Immobilization technology appears as a beneficial solution to the uneconomical cost of enzyme operation. Immobilization of enzyme via crosslinking approach has become a technology interest due to the more concentrate enzyme activity in the catalyst compared to other techniques. In this study, two types of crosslinker, glutaraldehyde and hexamethylene diisocyanate at different concentration was investigated in immobilizing β-galactosidase on polymethacrylate monolith. The enzyme activity upon immobilization was measured spectrophotometrically at 405 nm. The immobilized enzyme was further characterized using Fourier Transform Infrared Spesctroscopy (FTIR) and Zeiss Axio Fluorescence Microscope. The findings showed that the optimum enzyme activity was achieved when using 0.05% and 0.01% glutaraldehyde hexamethylene diisocyanate respectively. Beyond that concentration, a significant reduction of enzyme activity was observed. It was found that glutaraldehyde was preferable as crosslinking agent as hexamethylene diisocyanate exhibited stronger effect in reducing enzyme activity. A successful binding of β-galactosidase on polymethacrylate monolith was observed using Fourier-transform infrared spectroscopy (FTIR) and Zeiss Axio Fluorescence microscope. The outcomes of this study indicate the potential of enzyme immobilization on monolith via crosslinking method

Preparation of Polystyrene Microsphere-Templated Porous Monolith for Wastewater Filtration

Porous monoliths prepared using templates are highly sought after for filtration applications due to their good mass transport properties and high permeability. Current templates, however, often lead to the formation of dead-end pores and irregular pore distributions, which reduce the efficiency of the substrate flow across the monolith column. This study focused on the preparation of a microsphere-templated porous monolith for wastewater filtration. The optimal template/monomer ratio (50:50, 60:40, 70:30) was determined, and appropriate template removal techniques were assessed for the formation of homogenous pores. The physicochemical characteristics and pore homogeneity of the monoliths were examined. The 60:40 ratio was determined to result in monoliths with homogeneous pore distributions ranging from 1.9 µm to 2.3 µm. SEM and FTIR investigations revealed that solvent treatment was effective for removing templates from the resulting solid monolith. The water quality assessments revealed reductions in the turbidity and the total number of suspended particles in the tested wastewater of up to 96–99%. The findings of this study provide insightful knowledge regarding the fabrication of monoliths with homogenous pores that are beneficial for wastewater treatment

Synthesis and characterization of polymeric microspheres template for a homogeneous and porous monolith

Monolith is an emerging technology applicable for separation, filtration, and chromatography due to its interconnected pore structure. However, the current templates used to form monolith pores are associated with poor heat dissipation, uneven pore size distribution, and relatively low mechanical strength during monolith scale-up. Templates made from polymeric microsphere particles were synthesized via a solvent evaporation technique using different types of polymer (polystyrene, polycaprolactone, polypropylene, polyethylene, and poly (vinyl-alcohol) at varied polymer (10–40 wt%) and surfactant (5–10%) concentrations. The resulting microsphere particles were tested as a monolith template for the formation of homogenous pores. Among the tested polymers, polystyrene at 10 wt% concentration demonstrated good particle morphology determined to around 1.94–3.45 µm. The addition of surfactant at a concentration of 7–10 wt% during microsphere synthesis resulted in the formation of well-shaped and non-aggregating microsphere particles. In addition, the template has contributed to the production of porous monoliths with enhanced thermal stability. The thermogravimetric analysis (TGA) indicated monolith degradation between 230 ◦C and 450 ◦C, implying the material excellent mechanical strength. The findings of the study provide insightful knowledge on the feasibility of polymeric microsphere particles as a pore-directing template to fabricate monoliths with desired pore structures

UTILIZAÇÃO DA PROGRESSÃO ARITMÉTICA DO COEFICIENTE DE CORRELAÇÃO DE PEARSON PARA PREVISÃO DA DESCARACTERIZAÇÃO SUPERFICIAL DE ROCHAS ORNAMENTAIS.

No envelhecimento acelerado de rochas ornamentais em câmara saturada em SO2, as interações físico-químicas têm o objetivo de simular a exposição das mesmas às chuvas ácidas. As presenças de SO2, de H2O, somadas à incidência de radiação solar (externa) permitem a formação fotoquímica do ácido sulfúrico (H2SO4) e a correlação entre as digitalizações das superfícies dos corpos de prova, antes e após as exposições ao H2SO4, propicia a análise da evolução das alterações causadas. A estimativa do tempo gasto, em anos, para que as alterações descaracterizem totalmente a aparência estética da superfície das amostras é feita com a progressão aritmética do coeficiente de correlação linear de Pearson (r) que permite, quando igual a 0 (zero), afirmar a inexistência de correlação entre imagens de amostras submetidas ao ensaio e suas imagens originais ao natural. Os resultados apontam o Butterfly Gold como o mais susceptível à descaracterização estética superficial (3,08 anos), seguido do Butterfly Green (3,91 anos) e do Butterfly Beige (16,03 anos). Ressalta-se que a descaracterização não implica, necessariamente, em alteração ou comprometimento estrutural ou físico-mecânico da rocha. A concentração do gás na câmara (25 ppm) foi superelevada propositalmente para acelerar o processo de deterioração. É importante lembrar que a câmara simula as condições climáticas em fluxo praticamente contínuo necessitando o pesquisador, para as interpretações, considerar a concentração de SO2 na atmosfera, a duração das estações chuvosas, a incidência de chuvas ácidas e suas intensidades ao longo de um ano nos diferentes territórios. As previsões aqui realizadas não são impeditivos para aplicação destes materiais em ambientes externos nem tampouco internos, pois procedimentos usuais de limpeza podem ser perfeitamente aplicados para conservação dos mesmos

Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes

Soil respiration (SR) constitutes the largest flux of CO₂ from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (〖SR〗_MAT), irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q₁₀). We further show that for seasonally dry sites where annual precipitation (P) is lower than potential evapotranspiration (PET), annual SR can be predicted from wet season SRMAT corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure 〖SR〗_MAT for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO₂ emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle