Ethanol-assisted kneading of apigenin with arginine for enhanced dissolution rate of apigenin: development of rapidly disintegrating tablets.

Apigenin is a natural flavonoid which is claimed to have many pharmacological activities ranging from simple anti-inflammatory to anticancer action. However, poor dissolution slowed the advancement of this drug through the development pipelines. The objective of this work was to probe ethanol-aided kneading of apigenin with arginine as a new strategy for enhanced dissolution rate. The work was extended to develop rapidly disintegrating tablets of apigenin. Apigenin was mixed with increasing molar ratios of arginine before ethanol-aided kneading. The resulting products were examined using Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction in addition to probing the dissolution characteristics of apigenin. The analytical techniques highlighted the existence of new crystalline species with a possibility of salt formation. The recorded alterations in the crystalline properties were associated with a significant enhancement in the dissolution rate of apigenin. The presence of arginine did not have any negative effect of the cytotoxic power of apigenin. Optimum formulation was successfully prepared as rapidly disintegrating tablets which showed fast liberation of apigenin. The study introduced arginine as a potential excipient for enhanced dissolution of apigenin after ethanol-assisted kneading.

Adaptive evolution and selection of stress-resistant Saccharomyces cerevisiae for very high-gravity bioethanol fermentation

Background: In industrial yeasts, selection and breeding for resistance to multiple stresses is a focus of current research. The objective of this study was to investigate the tolerance to multiple stresses of Saccharomyces cerevisiae obtained through an adaptive laboratory evolution strategy involving a repeated liquid nitrogen freeze­thaw process coupled with multi-stress shock selection. We also assessed the related resistance mechanisms and very high-gravity (VHG) bioethanol production of this strain. Results: Elite S. cerevisiae strain YF10-5, exhibiting improved VHG fermentation capacity and stress resistance to osmotic pressure and ethanol, was isolated following ten consecutive rounds of liquid nitrogen freeze­thaw treatment followed by plate screening under osmotic and ethanol stress. The ethanol yield of YF10-5 was 16% higher than that of the parent strain during 35% (w/v) glucose fermentation. Furthermore, there was upregulation of three genes (HSP26, HSP30, and HSP104) encoding heat-shock proteins involved in the stress response, one gene (TPS1) involved in the synthesis of trehalose, and three genes (ADH1, HXK1, and PFK1) involved in ethanol metabolism and intracellular trehalose accumulation in YF10-5 yeast cells, indicating increased stress tolerance and fermentative capacity. YF10-5 also showed excellent fermentation performance during the simultaneous saccharification and fermentation of VHG sweet potato mash, producing 13.40% (w/ v) ethanol, which corresponded to 93.95% of the theoretical ethanol yield. Conclusions: A multiple-stress-tolerant yeast clone was obtained using adaptive evolution by a freeze­thaw method coupled with stress shock selection. The selected robust yeast strain exhibits potential for bioethanol production through VHG fermentation.

Improvement of ethanol production from birch and spruce pretreated with 1-H-3-methylmorpholinium chloride

Background: Pretreatment is the critically important step for the production of ethanol from lignocelluloses. In this study, hardwood birch (Betula pendula) and softwood spruce (Norway spruce) woods were pretreated with a newly synthesized morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]), followed by enzymatic hydrolysis and fermentation to ethanol. Results: [HMMorph][Cl] was synthesized using inexpensive raw materials, i.e., hydrochloric acid and N-methyl morpholine, following a simple process. The influence of pretreatment time (2, 3, 5, and 8 h) and temperature (120 and 140°C) in terms of hydrolysis efficiency was investigated. Glucose yields from enzymatic hydrolysis were improved from 13.7% to 45.7% and 12.9% to 51.8% after pretreatment of birch and spruce woods, respectively, under optimum pretreatment conditions (i.e., at 140°C for 3 h) as compared to those from pristine woods. Moreover, the yields of ethanol production from birch and spruce were increased to 34.8% and 44.2%, respectively, while the yields were negligible for untreated woods. Conclusions: This study demonstrated the ability of [HMMorph][Cl] as an inexpensive agent to pretreat both softwood and hardwood.

Kinetic modeling of the simultaneous production of ethanol and fructose by Saccharomyces cerevisiae

Background: Ethanol and fructose are two important industrial products that enjoy many uses. In this contribution, their production via selective fermentation of date extract using Saccharomyces cerevisiae was studied. Scaling up the process for possible commercialization was investigated in three fermentors with working volume ratio of 1:40:400. Results: Higher ethanol concentration was obtained in the larger fermentor due to conversion of fructose. Fructose yields in the 0.5-L, 7.5-L and 80-L fermentors were 99, 92 and 90%, respectively. Good fitting was obtained with the modified Monod kinetics; however, a better fit of cell mass was obtained with the modified Ghose­Tyagi model which accounts for ethanol inhibition. Conclusions: The modified Gompertz model was expanded to facilitate prediction of products' formation and fructose fractions in all three fermentors. Such expansion will be beneficial in industrial applications.

Cytocompatible Fabrication of Yeast Cells/Fabrics Composite Sheet for Bioethanol Production.

Entrapment of living cells into a polymer network has significant potential in various fields such as biomass conversion and tissue engineering. A crucial challenge for this strategy is to provide a mild enough condition to preserve cell viability. Here, a facile and cytocompatible method to entrap living yeast cells into a poly(ethylene glycol) (PEG) network grafting from polypropylene nonwoven fabrics via visible-light-induced surface living graft crosslinking polymerization is reported. Due to the mild reaction conditions and excellent biocompatibility of PEG, the immobilized yeast cells could maintain their viability and proliferate well. The obtained composite sheet has excellent long-term stability and shows no significant efficiency loss after 25 cycles of repeated batch bioethanol fermentation. The immobilized yeast cells exhibit 18.0% higher bioethanol fermentation efficiency than free cells. This strategy for immobilization of living cells with high viability has significant potential application.

Transfection efficiencies of α-tocopherylated cationic gemini lipids with hydroxyethyl bearing headgroups under high serum conditions.

Herein, five new α-tocopheryl cationic gemini lipids with hydroxyethyl bearing headgroups (THnS, n = 4, 5, 6, 8, 12) have been synthesized for efficient plasmid DNA (pDNA) delivery into cancer cells. Among these gemini lipid formulations, the lipid with an octamethylene [-(CH2)8] spacer (TH8S) showed the highest transfection efficiency (TE) that was comparable to that of the commercial standard lipofectamine 2000 (L2K) in terms of luciferase expression in HepG2 (liver hepatocellular carcinoma) cells. The addition of the helper lipid DOPE (1,2-dioleoyl phosphatidyl ethanolamine) with cationic lipids in mixed liposomes further enhanced the TE and the optimized molar ratio was 2 : 1 (DOPE : cationic lipid). The optimized co-liposomal formulation of TH8S (DOPE : TH8S = 2 : 1) showed a higher TE in HepG2, A549 (human lung carcinoma) and MCF7 (human breast adenocarcinoma) cells than other optimized co-liposomal formulations and was also significantly more potent than L2K. The comparison of the TE of DOPE-TH8S (2 : 1) with the gemini lipid T8T (the headgroup devoid of the hydroxyl group) further demonstrated the importance of the hydroxyethyl functionality at the level of the headgroup. Relatively good binding efficiency and easy release of pDNA (pGL3) were also observed with DOPE-TH8S (2 : 1) in the ethidium bromide (EB)-exclusion and re-intercalation assay, which may be the plausible reason for high TE. The lipoplexes were also characterized by atomic force microscopy (AFM), dynamic light scattering (DLS), zeta potential and small angle X-ray diffraction experiments. Greater cellular internalization of fluorescein tagged pDNA was also observed with DOPE-TH8S (2 : 1) lipoplexes compared to that with L2K. Retention of the TE of DOPE-TH8S (2 : 1) lipoplexes under high serum conditions was conferred by the presence of the tocopherol backbone and also the hydroxyethyl functionalities. The cellular internalization pathway of the lipoplexes was characterized by performing transfection experiment in the presence of inhibitors of different endocytic pathways and it was found to be caveolae mediated. An MTT based cell viability assay indicated that the lipoplex mediated gene delivery vectors exhibited low toxicity in all the three cancer cell lines studied.

Single mutations of ketoreductase ChKRED20 enhance the bioreductive production of (1S)-2-chloro-1-(3, 4-difluorophenyl) ethanol.

(1S)-2-chloro-1-(3, 4-difluorophenyl) ethanol ((S)-CFPL) is an intermediate for the drug ticagrelor, and is manufactured via chemical approaches. To develop a biocatalytic solution to (S)-CFPL, an inventory of ketoreductases from Chryseobacterium sp. CA49 were rescreened, and ChKRED20 was found to catalyze the reduction of the ketone precursor with excellent stereoselectivity (>99 % ee). After screening an error-prone PCR library of the wild-type ChKRED20, two mutants, each bearing a single amino acid substitution of H145L or L205M, were identified with significantly increased activity. Then, the two critical positions were each randomized by constructing saturation mutagenesis libraries, which delivered several mutants with further enhanced activity. Among them, the mutant L205A was the best performer with a specific activity of 178 µmol/min/mg, ten times of that of the wild-type. Its k cat/K m increased by 15 times and half-life at 50 °C increased by 70 %. The mutant catalyzed the complete conversion of 150 and 200 g/l substrate within 6 and 20 h, respectively, to yield enantiopure (S)-CFPL with an isolated yield of 95 %.

[Distiller Yeasts Producing Antibacterial Peptides].

A new method of controlling lactic acid bacteria contamination was developed with the use of recombinant Saccharomyces cerevisiae strains producing antibacterial peptides. Genes encoding the antibacterial peptides pediocin and plantaricin with codons preferable for S. cerevisiae were synthesized, and a system was constructed for their secretory expression. Recombinant S. cerevisiae strains producing antibacterial peptides effectively inhibit the growth of Lactobacillus sakei, Pediacoccus pentasaceus, Pediacoccus acidilactici, etc. The application of distiller yeasts producing antibacterial peptides enhances the ethanol yield in cases of bacterial contamination. Recombinant yeasts producing the antibacterial peptides pediocin and plantaricin can successfully substitute the available industrial yeast strains upon ethanol production.

Mechanism of Oxidation of Ethane to Ethanol at Iron(IV)-Oxo Sites in Magnesium-Diluted Fe2(dobdc).

The catalytic properties of the metal-organic framework Fe2(dobdc), containing open Fe(II) sites, include hydroxylation of phenol by pure Fe2(dobdc) and hydroxylation of ethane by its magnesium-diluted analogue, Fe0.1Mg1.9(dobdc). In earlier work, the latter reaction was proposed to occur through a redox mechanism involving the generation of an iron(IV)-oxo species, which is an intermediate that is also observed or postulated (depending on the case) in some heme and nonheme enzymes and their model complexes. In the present work, we present a detailed mechanism by which the catalytic material, Fe0.1Mg1.9(dobdc), activates the strong C-H bonds of ethane. Kohn-Sham density functional and multireference wave function calculations have been performed to characterize the electronic structure of key species. We show that the catalytic nonheme-Fe hydroxylation of the strong C-H bond of ethane proceeds by a quintet single-state σ-attack pathway after the formation of highly reactive iron-oxo intermediate. The mechanistic pathway involves three key transition states, with the highest activation barrier for the transfer of oxygen from N2O to the Fe(II) center. The uncatalyzed reaction, where nitrous oxide directly oxidizes ethane to ethanol is found to have an activation barrier of 280 kJ/mol, in contrast to 82 kJ/mol for the slowest step in the iron(IV)-oxo catalytic mechanism. The energetics of the C-H bond activation steps of ethane and methane are also compared. Dehydrogenation and dissociation pathways that can compete with the formation of ethanol were shown to involve higher barriers than the hydroxylation pathway.

Balance de Flujos Metabólicos en Saccharomyces cerevisiae basado en Compartimentalización Intracelular / Metabolic Flows Balance in Saccharomyces cerevisiae based on Intracellular Compartmentalization

Una de las técnicas más utilizadas para la predicción de producción de bioproductos y distribución intracelular de flujos de microorganismos es el Análisis de Balance de Flujos - FBA por sus siglas en inglés. El FBA requiere de una función objetivo que represente el objetivo biológico del microorganismo estudiado. En este trabajo se propone un nuevo tipo de funciones objetivo basada en la combinación de objetivos de compartimentos físicos presentes en el microorganismo estudiado. Este tipo de funciones objetivo son examinadas junto con un modelo estequiométrico extraído de la reconstrucción iMM904 del microorganismo S. cerevisiae. Su desempeño se compara con la función objetivo más usada en la literatura, la maximización de biomasa, en condiciones experimentales anaeróbicas en cultivos continuos y aeróbicas en cultivos tipo lote. La función objetivo propuesta en este trabajo mejora las predicciones de crecimiento en un 10% y las predicciones de producción de etanol en un 75% respecto a las obtenidas por la función objetivo de maximización de biomasa, en condiciones anaeróbicas. En condiciones aeróbicas tipo lote la función objetivo propuesta mejora en un 98% las predicciones de crecimiento y en un 70% las predicciones de etanol con respecto a la función objetivo de biomasa.

Flux Balance Analysis - FBA - is one of the most used techniques in prediction of microorganism bioproducts. It requires an objective function that represents biological objective of the studied microorganism. This paper presents a new kind of objective functions based on individual physical compartment objetives in the studied microorganism. These kind of functions was tested with a stoichiometric model extracted from iMM904 reconstruction of S. cerevisiae and its performance is compared with the most used objective function in literature, growth maximization, in anaerobic and aerobic batch conditions. The presented objective function outperform growth predictions in 10% and ethanol predictions in 75% compared with obtained by maximization of growth objective function, in anaerobic conditions. In aerobic batch conditions the presented objective function outperforms in 98% growth preditions and 70% ethanol predictions compared with growth maximization.

Microcontact imprinting of algae on poly(ethylene-co-vinyl alcohol) for biofuel cells.

Hydrogen can be produced using microorganisms (e.g., bacteria and algae); algal production has the additional ecological benefit of carbon dioxide fixation. The conversion of hydrogen to electricity via fuel cells may be more efficient compared to other energy sources of electricity. However, the anode of biofuel cells requires the immobilization of microorganisms or enzymes. In this work, poly(ethylene-co-vinyl alcohol) (EVAL), was coated on the electrode, and green algae was microcontact imprinted onto the EVAL film. The readsorption of algae onto algae-imprinted EVAL thin films was compared to determine the ethylene content that gave highest imprinting effectiveness and algal binding. Scanning electron microscopy and fluorescence spectrometry were employed to characterize the surface morphology, recognition capacity, and reusability of the algae-imprinted cavities. The recognition of an individual algal cell by binding to the imprinted cavities was directly observed by video microscopy. Finally, the power and current density of the algal biofuel cell using the algae-imprinted EVAL-coated electrode were measured at about 2-fold higher than electrode sputtered platinum on poly(ethylene terephthalate).

Estudio comparativo de los efectos de hidrato de cloral y etanol en ratas expuestas a fluoracetato de sodio / Comparative study of the effects of cloral hydrate and ethanol in rats exposed to sodium fluoracetate

El fluoroacetato de sodio, es un raticida prohibido en algunos países y permitido en otros, que causa severas intoxicaciones humanas y animales. Actúa por inhibición del ciclo de Krebs e interfiere con la producción de energía, lo cual conduce a disfunción celular irreversible, especialmente en sistema nervioso central y corazón. El alcohol etílico, debido a su oxidación a acido acético y a su amplia disponibilidad, es uno de los fármacos usados en esta intoxicación, lo que podría causar controversias éticas y legales. La biotransformación del hidrato de cloral a tricloroetanol y a ácido tricloroacético, el efecto anticonvulsivante y su amplio uso en Pediatría, fueron las razones para su evaluación en la intoxicación por fluoroacetato. Se realizó un estudio experimental, para comparar los efectos de hidrato de cloral y alcohol en ratas intoxicadas con fluoroacetato de sodio. El análisis estadístico aplicado fue la prueba de chi cuadrado. Los resultados mostraron que el hidrato de cloral a dosis bajas, permite la sobrevivencia en 100% de los animales expuestos. Se confirmó igualmente la efectividad del alcohol etílico a dosis altas. Este resultado sugiere que el hidrato de cloral puede ser una opción tan útil como el etanol y que podría ser el fármaco de elección en aquellos pacientes que no puedan recibir monoacetin o etanol o porque haya mayor accesibilidad al hidrato de cloral.

Sodium fluoroacetate is a banned rodenticide in some countries and allowed in others, which causes severe human and animal poisonings. It acts for inhibition of Krebs's cycle and interferes with energy production leading to irreversible cellular dysfunction, specially in nervous central system and heart. Ethyl alcohol, because oxidation to acetic acid and to its wide availability, is one of the drugs used in this poisoning, which should can cause ethical and legal controversies. Biotransformation of chloral hydrate to trichloroethanol and trichloroacetic acid, the anticonvulsant effect and its widespread use in Pediatrics, were the reasons for its evaluation in fluoroacetate poisoning. An experimental study was conducted, to compare effects of chloral hydrate and ethanol in poisoned rats with sodium fluoroacetate. The statistical analysis applied was the chi square test. The results showed that chloral hydrate in low doses allows survival in 100 % of the exposed animals. It also confirms the effectiveness of ethyl alcohol at high doses. This result suggests that chIoral hydrate may be an option as useful as ethanol and could be the choice drug in those patients who could not receive monoacetin or ethanol or because there is greater accessibility to chloral hydrate.

Evaluación del pretratamiento con ácido sulfúrico diluido del pasto maralfalfa (Pennisetum glaucum x Pennisetum purpureum) para la producción de etanol / Dilute sulfuric acid pretreatment of goliath grass (Pennisetum glaucum x Pennisetum purpureum) for ethanol cellulosic

Evaluar la producción de etanol a partir de cultivos lignocelulósicos, específicamente pastos de rápido crecimiento en la región, constituye una alternativa a la demanda de biocombustibles. En la presente investigación se seleccionó el pasto Maralfalfa (Pennisetum glaucum x Pennisetum purpureum) utilizando el pretratamiento con ácido sulfúrico diluido a diferentes temperaturas (110, 130, 150, 170 y 190 °C) y concentraciones de ácido (0.8, 1.2 y 2.0% (p/p)), seguido de un proceso de hidrólisis enzimática utilizando celulasas y celobiosas comerciales y un proceso de hidrólisis y fermentación simultanea. La máxima producción de etanol obtenido fue 117 mg etanol/ g biomasa pretratada a 190 °C y 1,2 %(p/p) de ácido sulfúrico. El líquido hidrolizado fue caracterizado calculando el porcentaje de glucosa, xilosa y lignina solubilizadas y degradadas durante el pretratamiento.

The goliath grass (Pennisetum glaucum x Pennisetum purpureum) was pretreated with different sulfuric acid concentrations (0.8, 1.2 y 2.0% (w/w)) from low to high temperatures (110, 130, 150, 170 y 190 °C) followed by enzymatic hydrolysis and SSF of remaining solids. The maximum yield was 117 mg of ethanol/g biomass to 190 °C and 1.2 % (w/w) of sulfuric acid.

[Tobacco--a source of biofuels]. / Tyton zródlem biopaliw.

One of the concepts of global protection of environment is to reduce greenhouse gas emissions, mainly carbon dioxide, into the atmosphere by replacing fossil fuels by the so-called biofuels, which can be obtained from cultivated plants or any plant waste biomass. Currently applied industrial technologies allow the production of biofuels to receive ethanol, mostly from the reserve carbohydrates of sugar cane and corn as well as biodiesel from oil, mainly from rapeseed or oil palm. Tobacco, which provides a high biomass, can be used to produce biogas, bioethanol and biodiesel. The latter derived from oil from seeds and leaves of tobacco has proved useful for driving cars. Modest oil content in tobacco leaves can be increased by the expression of foreign genes encoding its biosynthesis. Promising future source of biofuels is a waste plant biomass consisting mainly of cell walls, which can be subjected to the degradation to produce sugars suitable for fermentation and the production of bioethanol. A number of enzymes needed for efficient degradation of plant cell walls can be produced using recombinant DNA technology in a variety of plants, particularly in chloroplasts of tobacco.

The evaluation of various kinetic models for base-catalyzed ethanolysis of palm oil.

In this paper, the kinetics of palm oil ethanolysis with various models have been investigated in a temperature range of 25-55 °C. The highest yield was achieved when the conversion to ethyl ester was 97.5±0.5% in the stated temperature range, using ethanol:oil molar ratio of 12:1, and 1.0 wt.% sodium ethoxide. The level of conformity of the reaction with reversible second order, irreversible second order and first order kinetic models were evaluated by means of the R(2) values of the linear curves. The ethanolysis showed the best conformity with irreversible second order kinetic model with 92-98% level of confidence. The reaction rate constants were within 0.018-0.088 dm(3)/mol min and the activation energy of the reaction was 42.36 kJ/mol.

Efecto de diámetro de esfera y densidad celular en la producción de etanol con levadura inmovilizada en alginato / Effect of pellet diameter and cell density on ethanol production with alginate immobilized yeast

Las células inmovilizadas tienen aplicación potencial en la producción de biocombustibles posibilitando la reutilización de biomasa, el empleo de diversas configuraciones de reactores y sistemas de cultivo, el manejo de altas densidades celulares alcanzando altas productividades volumétricas, y la simplificación de operaciones de procesamiento de salida. El objetivo del presente estudio fue evaluar la influencia del diámetro de las perlas y la densidad celular en la producción de etanol con Saccharomyces uvarum inmovilizada en alginato al 2% (p/v). Para ello se evaluaron tres diámetros de perlas de 2, 2,5 y 3 mm. Las células inmovilizadas fueron cultivadas en medio con 12% (p/v) de glucosa en biorreactores de columna sin agitación a 28 ºC, y se operaron cuatro lotes consecutivos de 48 horas cada uno. En cada lote se cuantificó el consumo de glucosa y se determinó la cantidad de etanol producido. Los rendimientos máximos de etanol para las esferas de 2, 2,5 y 3 mm de diámetro fueron 81, 83 y 97% del rendimiento teórico. La máxima productividad volumétrica de etanol fue 1,2 g/L-1/h-1 con un consumo de glucosa de 99,8% al término del lote, correspondiente a las columnas con perlas de 3 mm y con una producción de 0,017 g de etanol por esfera. La producción de etanol acumulada en cada sistema fue 178, 189 y 200 g/L-1 para 2, 2,5 y 3 mm respectivamente, encontrándose una relación directa con el diámetro de perla e inversa respecto a la densidad celular. Los rendimientos de etanol obtenidos son superiores a los reportados para la misma especie.

Immobilized cells have a potential use in biofuel production. They also allow re-using biomass, using diverse reactor configurations and culture systems, handling high cell densities to obtain high volumetric productivities and to simplify the downstream processing. The purpose of this work was to evaluate the influence of bead diameter and cell density on ethanol production using immobilized Saccharomyces uvarum in 2% (w/v) alginate. For that, three bead diameters (2, 2.5 and 3 mm) were evaluated. Immobilized cells were cultured on a 12% (w/v) glucose medium in column bioreactors without agitation at 28 °C for four 48 h–repeated batches. For each batch, both glucose consumption and ethanol produced were measured. Maximum yields for 2, 2.5 and 3 mm bead diameters were 81, 83 and 97% of theoretical yield. Maximum volumetric productivity of ethanol was 1.2 g/L-1/h-1 with 99.8% glucose consumption at the end of the batch, corresponding to the 3 mm bead diameter and the ethanol production per bead was 0.017 g. Accumulated ethanol production for each system was 178, 189 and 200 g/L-1 for 2, 2.5 y 3 mm bead diameter, respectively, being this directly related to bead diameter and inversely related to cell density. Ethanol yields were higher than those reported for the same species.

Greenhouse gas emissions from biofuels' indirect land use change are uncertain but may be much greater than previously estimated.

The life cycle greenhouse gas (GHG) emissions induced by increased biofuel consumption are highly uncertain: individual estimates vary from each other and each has a wide intrinsic error band. Using a reduced-form model, we estimated that the bounding range for emissions from indirect land-use change (ILUC) from US corn ethanol expansion was 10 to 340 g CO(2) MJ(-1). Considering various probability distributions to model parameters, the broadest 95% central interval, i.e., between the 2.5 and 97.5%ile values, ranged from 21 to 142 g CO(2)e MJ(-1). ILUC emissions from US corn ethanol expansion thus range from small, but not negligible, to several times greater than the life cycle emissions of gasoline. The ILUC emissions estimates of 30 g CO(2) MJ(-1) for the California Air Resources Board and 34 g CO(2)e MJ(-1) by USEPA (for 2022) are at the low end of the plausible range. The lack of data and understanding (epistemic uncertainty) prevents convergence of judgment on a central value for ILUC emissions. The complexity of the global system being modeled suggests that this range is unlikely to narrow substantially in the near future. Fuel policies that require narrow bounds around point estimates of life cycle GHG emissions are thus incompatible with current and anticipated modeling capabilities. Alternative policies that address the risks associated with uncertainty are more likely to achieve GHG reductions.

Avaliação in vitro do extrato hidroalcoólico (EHA) de alecrim pimenta (Lippia sidoides Cham. ) sobre o desenvolvimento de ovos de nematódeos gastrointestinais (Trichostrongylidae) / In vitro evaluation of alecrim pimenta (Lippia sidoides Cham. ) hydroalcoholic extract (HAE) on the development of gastrointestinal nematode (Trichostrongylidae) eggs

Atualmente a fito medicina vem sendo usada no controle de diversas doenças parasitárias particularmente as parasitoses gastrointestinais. Objetivou-se com este estudo avaliar a eficácia do extrato hidroalcoólico (EHA) de Lippia sidoides Cham sobre o desenvolvimento de ovos de nematódeos gastrointestinais. O efeito ovicida foi determinado através de análise probabilística, modelo logístico, utilizados os softwares R versão 2.2.1 e EPI6. Foram obtidos ovos embrionados em fezes de cabras naturalmente infectadas com nematóides Trichostrongylidae e o número de ovos fecais foi determinado usando-se a técnica modificada de McMaster. Cinquenta μL da suspensão contendo 40 ovos foram transferidas a placas de poliestireno e incubadas com 12 concentrações diferentes do EHA sendo avaliada durante 72 horas a temperatura ambiente. Os resultados demonstraram diferentes eficácias para o fito medicamento com menor taxa de desenvolvimento de ovos na concentração de 500 mg mL-1 . Conclui-se que o EHA pode ter papel importante sobre o desenvolvimento in vitro de ovos de nematóides gastrintestinais, revelando atividade ovicida.

Phytomedicine has been currently used in the control of several parasitic diseases, particularly gastrointestinal ones. The aim of this study was to evaluate the efficacy of the hydroalcoholic extract (HAE) from Lippia sidoides Cham. on the development of gastrointestinal nematode eggs. The ovicidal effect was determined through probabilistic analysis, logistic model, by using the programs R version 2.2.1 and Epi InfoTM 6. Embryonated eggs were obtained from feces of goats naturally infected with Trichostrongylidae nematodes and the fecal egg count was determined by using the modified McMaster technique. Fifty microliters of the suspension containing 40 eggs were transferred to polystyrene plates and incubated with 12 different HAE concentrations, and evaluations were performed during 72h at room temperature. The results demonstrated different efficacy of extracts, with lower egg development rate at 500 mg mL-1. In conclusion, HAE may play an important role on the in vitro development of gastrointestinal nematode eggs, indicating ovicidal activity.

Evaluation of supplementation of sucrose medium on the synthesis of Zymomonas mobilis bio-products / Avaliação da suplementação do meio de sacarose na formação de bio–produtos por Zymomonas mobilis

The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.

A influência das variáveis: ácido pantotênico, extrato de levedura, cloreto de sódio, e a técnica de permeabilização celular foram investigadas na formação de levana, sorbitol, etanol e biomassa de Zymomonas mobilis utilizando um delineamento estatístico fatorial fracionado 24-1. A biomassa foi determinada por turbidimetria, Os açúcares redutores foram quantificados por Somogy e Nelson, açúcar total por Fenol Sulfúrico, sorbitol por HPLC e etanol por micro-destilação. A levana produzida foi precipitada com etanol absoluto e determinada como unidade de frutose. Na biossíntese de levana, a variável que mais contribuiu foi a condição celular. Os resultados sugerem que, para a formação da biomassa e etanol, os fatores que mais interferiram foram a concentração de cloreto de sódio e a condição celular que influencia negativamente a produção. Para o sorbitol, a variável que teve efeito significativo foi a permeabilização celular que atuou diminuindo a sua síntese. Estudos que ampliam a faixa de variação dos fatores estabelecidos são interessantes.