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1.
Bioresour Technol ; 199: 59-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26338276

RESUMO

Mechanical refining is widely used in the pulp and paper industry to enhance the end-use properties of products by creating external fibrillation and internal delamination. This technology can be directly applied to biochemical conversion processes. By implementing mechanical refining technology, biomass recalcitrance to enzyme hydrolysis can be overcome and carbohydrate conversion can be enhanced with commercially attractive levels of enzymes. In addition, chemical and thermal pretreatment severity can be reduced to achieve the same level of carbohydrate conversion, which reduces pretreatment cost and results in lower concentrations of inhibitors. Refining is versatile and a commercially proven technology that can be operated at process flows of ∼ 1500 dry tons per day of biomass. This paper reviews the utilization of mechanical refining in the pulp and paper industry and summarizes the recent development in applications for biochemical conversion, which potentially make an overall biorefinery process more economically viable.


Assuntos
Biomassa , Carboidratos/química , Carboidratos/economia , Lignina/química , Fenômenos Mecânicos , Hidrólise
2.
Bioresour Technol ; 187: 37-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25836372

RESUMO

Solid-liquid separation of intermediate process slurries is required in some process configurations for the conversion of lignocellulosic biomass to transportation fuels. Thermochemically pretreated and enzymatically hydrolyzed corn stover slurries have proven difficult to filter due to formation of very low permeability cakes that are rich in lignin. Treatment of two different slurries with polyelectrolyte flocculant was demonstrated to increase mean particle size and filterability. Filtration flux was greatly improved, and thus scaled filter unit capacity was increased approximately 40-fold compared with unflocculated slurry. Although additional costs were accrued using polyelectrolyte, techno-economic analysis revealed that the increase in filter capacity significantly reduced overall production costs. Fuel production cost at 95% sugar recovery was reduced by $1.35 US per gallon gasoline equivalent for dilute-acid pretreated and enzymatically hydrolyzed slurries and $3.40 for slurries produced using an additional alkaline de-acetylation preprocessing step that is even more difficult to natively filter.


Assuntos
Carboidratos/economia , Carboidratos/isolamento & purificação , Hidrolases/química , Esgotos/química , Extração em Fase Sólida/métodos , Zea mays/química , Simulação por Computador , Hidrolases/economia , Hidrólise , Modelos Econômicos , Componentes Aéreos da Planta/química , Estados Unidos
3.
Public Health Nutr ; 18(12): 2263-73, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25430945

RESUMO

OBJECTIVE: To examine the characteristics of supporters and opponents of a sugar-sweetened beverage (SSB) tax and to identify pro-tax messages that resonate with the public. DESIGN: A survey was administered by telephone in February 2013 to assess public opinion about a penny-per-ounce tax on SSB. Support was also examined for SSB consumption reduction and pro-tax messages. Individual characteristics including sociodemographics, political affiliation, SSB consumption behaviours and beliefs were explored as predictors of support using logistic regression. SETTING: A representative sample of voters was recruited from a Mid-Atlantic US state. SUBJECTS: The sample included 1000 registered voters. RESULTS: Findings indicate considerable support (50 %) for an SSB tax. Support was stronger among Democrats, those who believe SSB are a major cause of childhood obesity and those who believe childhood obesity warrants a societal intervention. Belief that a tax would be effective in lowering obesity rates was associated with support for the tax and pro-tax messages. Respondents reporting that a health-care provider had recommended they lose weight were less convinced by pro-tax messages. Women, Independents and those concerned about childhood obesity were more convinced by the SSB reduction messages. Overall, the most popular messages focused on the importance of reducing consumption among children without mentioning the tax. CONCLUSIONS: Understanding who supports and opposes SSB tax measures can assist advocates in developing strategies to maximize support for this type of intervention. Messages that focus on the effect of consumption on children may be useful in framing the discussion around SSB tax proposals.


Assuntos
Bebidas/economia , Opinião Pública , Impostos/economia , Adolescente , Adulto , Bebidas/análise , Peso Corporal , Carboidratos/administração & dosagem , Carboidratos/análise , Carboidratos/economia , Feminino , Humanos , Modelos Logísticos , Masculino , Mid-Atlantic Region , Análise Multivariada , Obesidade Infantil/economia , Obesidade Infantil/prevenção & controle , Projetos Piloto , Política , Inquéritos e Questionários , Adulto Jovem
5.
Food Nutr Bull ; 35(4): 440-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25639129

RESUMO

BACKGROUND: The global economic crisis in 2007/08 resulted in higher food prices, which increased household food expenditures while worsening the quantity and quality of food consumed, potentially leading to child undernutrition. OBJECTIVE: To characterize the relationship of the mean proportions of household expenditures on strategic foods with the prevalence of undernutrition (high stunting, wasting, and underweight) among children under 2 years of age in Indonesia. METHODS: The study used data from 437 districts from two nationally representative surveys conducted in 2007, the National Socioeconomic Survey (Susenas) and the Basic Health Research (Riskesdas). RESULTS: A higher mean proportion of household expenditure on soybeans was significantly associated with lower odds (3rd vs. 1st tertile) of prevalence of high wasting (OR, 0.51; 95% CI, 0.28 to 0.94; p =.031) and high underweight (OR, 0.09; 95% CI, 0.03 to 0.28; p < .0001). A lower mean proportion of household expenditure on sugar and cooking oil was significantly associated with lower odds of prevalence of high wasting (OR, 2.41; 95% CI, 1.37 to 4.23; p = .002) and high underweight (2nd vs. 1st tertile) (OR, 2.38; 95% CI, 1.05 to 5.41; p = .039). CONCLUSIONS: Among all strategic foods, a higher proportion of household expenditure on soybeans and a lower proportion of household expenditure on sugar and cooking oil are associated with lower odds of high wasting and underweight prevalence among children 0 to 23 months of age. The results indicate the need for promotion of consumption of fermented soybeans and education aiming at decreasing expenditure on sugar and cooking oil to increase consumption of more nutritious foods.


Assuntos
Alimentos/economia , Desnutrição/epidemiologia , Orçamentos , Carboidratos/economia , Custos e Análise de Custo , Gorduras Insaturadas na Dieta/economia , Características da Família , Humanos , Indonésia/epidemiologia , Lactente , Recém-Nascido , Valor Nutritivo , Razão de Chances , Glycine max/economia , Magreza/epidemiologia
6.
Food Chem ; 135(3): 1028-35, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22953820

RESUMO

The antioxidant activity and phytochemical composition (ascorbic acid, free sugars and phenolic compounds) of decoctions and infusions of wild and commercial samples of Tuberaria lignosa (Sweet) Samp. Aerial parts were evaluated and compared. Among wild samples, the effects of the drying method (freeze or shade-drying) on those parameters were studied. Infusion of the freeze-dried wild sample gave the highest levels of sugars, while infusion of shade-dried wild sample and decoction of the freeze-dried sample presented higher ascorbic acid and phenolic compounds content (including ellagitannins and flavonoids) than the other samples. The last two samples also revealed higher antioxidant activity, in some cases even higher than Trolox. Decoctions gave lower amounts of disaccharides than infusions, which seemed to be hydrolysed, increasing the content of monosaccharides. Commercial samples showed the lowest content in phenolic compounds, mainly in ellagitannins and flavonoids, and also the lowest antioxidant activity. This work gives scientific evidence to the traditional medicinal uses of wild Tuberaria lignosa, highlighting the interest of its decoctions and infusions as a source of bioactive compounds and functional beverages.


Assuntos
Antioxidantes/química , Ácido Ascórbico/química , Carboidratos/química , Química Farmacêutica/métodos , Cistaceae/química , Fenóis/química , Extratos Vegetais/química , Antioxidantes/economia , Antioxidantes/isolamento & purificação , Ácido Ascórbico/economia , Ácido Ascórbico/isolamento & purificação , Carboidratos/economia , Carboidratos/isolamento & purificação , Química Farmacêutica/economia , Fenóis/economia , Fenóis/isolamento & purificação , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação
8.
Pediatr Allergy Immunol ; 23(3): 240-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22360663

RESUMO

OBJECTIVE: To estimate the cost-effectiveness of using an extensively hydrolysed formula (eHF; Nutramigen) compared with an amino acid formula (AAF; Neocate) as first-line treatment for cow milk allergy (CMA) in the UK, from the perspective of the National Health Service (NHS). METHOD: A decision model was constructed depicting the treatment paths and associated resource use attributable to first-line management of CMA with the two formulae. The model was based on the case records of 145 AAF-treated infants and 150 matched eHF-treated patients from The Health Improvement Network (THIN) database [a nationally representative database of patients registered with general practitioners (GPs) in the UK]. The model estimated the costs and consequences of patient management over 12 months following their initial GP visit for CMA. RESULTS: Patients presenting with a combination of gastrointestinal symptoms and eczema accounted for 44% of all patients in both groups. Those with gastrointestinal symptoms alone and eczema alone accounted for up to a further 39% and 13%, respectively. Those with urticaria and faltering growth accounted for <5% and ≤6% of all patients, respectively. Patients' age and weight at presentation was a mean 2.6-2.8 months and 4.4 kg, respectively. It took a mean 2.2 months to start a formula after initially seeing a GP. Time to symptom resolution following the start of treatment was 1.2 months in both groups; hence, the mean number of symptom-free months during the 12 months following the initial GP visit was estimated to be 8.6 months in both groups. Patients treated with an eHF had a mean 13.1 GP visits over the 12 months compared to 17.5 visits made by AAF-treated patients (p < 0.001). The NHS cost of managing a CMA infant over the first 12 months following initial presentation to a GP was estimated to be £1853 and £3161 for an eHF-treated and AAF-treated patient, respectively. CONCLUSION: Starting treatment for CMA with an eHF was the cost-effective option, as there were no significant differences in clinical outcomes between the two groups. A prospective, randomized controlled trial would allow a definitive confirmation of these findings.


Assuntos
Aminoácidos/economia , Carboidratos/economia , Gorduras na Dieta/economia , Alimentos Formulados/economia , Fórmulas Infantis/economia , Hipersensibilidade a Leite/dietoterapia , Hidrolisados de Proteína/economia , Aminoácidos/administração & dosagem , Aminoácidos/química , Animais , Carboidratos/administração & dosagem , Carboidratos/química , Bovinos , Análise Custo-Benefício , Gorduras na Dieta/administração & dosagem , Feminino , Humanos , Lactente , Alimentos Infantis/economia , Fórmulas Infantis/química , Recém-Nascido , Masculino , Hipersensibilidade a Leite/fisiopatologia , Hidrolisados de Proteína/administração & dosagem , Hidrolisados de Proteína/química , Reino Unido
9.
Enterp Soc ; 11(4): 695-708, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21114068

RESUMO

Through an investigation into the origins of American food marketing, this dissertation reveals how branding­specifically, the centennial brands Quaker Oats, Coca-Cola, and Crisco­came to underpin much of today's market-driven economy. In a manner akin to alchemy, the entrepreneurs behind these three firms recognized the inherent value of an agricultural Eden, then found ways to convert common, low-cost agricultural goods­oats, sugar, and cottonseed oil­into appealing, high-revenue branded food products. In the process, these ventures devised new demand-driven business models that exploited technology and communications advances, enabling them to tap a nascent consumer culture. Their pioneering efforts generated unprecedented profits, laid the foundation for iconic billion-dollar brands, and fundamentally changed how Americans make daily food choices.


Assuntos
Produtos Agrícolas , Empreendedorismo , Indústria Alimentícia , Abastecimento de Alimentos , Marketing , Avena/economia , Avena/história , Carboidratos/economia , Carboidratos/história , Óleo de Sementes de Algodão/economia , Óleo de Sementes de Algodão/história , Produtos Agrícolas/economia , Produtos Agrícolas/história , Empreendedorismo/economia , Empreendedorismo/história , Indústria Alimentícia/economia , Indústria Alimentícia/educação , Indústria Alimentícia/história , Indústria Alimentícia/legislação & jurisprudência , Abastecimento de Alimentos/economia , Abastecimento de Alimentos/história , Abastecimento de Alimentos/legislação & jurisprudência , Tecnologia de Alimentos/economia , Tecnologia de Alimentos/educação , Tecnologia de Alimentos/história , Tecnologia de Alimentos/legislação & jurisprudência , História do Século XIX , História do Século XX , Marketing/economia , Marketing/educação , Marketing/história , Estados Unidos/etnologia
10.
J Diabetes Sci Technol ; 4(5): 1139-45, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20920433

RESUMO

With the advent of several innovative wound care management tools, the choice of products and treatment modalities available to clinicians continues to expand. High costs associated with wound care, especially diabetic foot wounds, make it important for clinician scientists to research alternative therapies and optimally incorporate them into wound care protocols appropriately. This article reviews using sugar as a treatment option in diabetic foot care and provides a guide to its appropriate use in healing foot ulcers. In addition to a clinical case study, the physiological significance and advantages of sugar are discussed.


Assuntos
Carboidratos/uso terapêutico , Pé Diabético/tratamento farmacológico , Cicatrização/fisiologia , Carboidratos/economia , Análise Custo-Benefício , Pé Diabético/fisiopatologia , Humanos , Resultado do Tratamento
12.
Appl Biochem Biotechnol ; 136(3): 361-88, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17625239

RESUMO

Little information is yet available on the economic viability of the production of bio-based bulk chemicals and intermediates from white biotechnology (WB). This paper details a methodology to systematically evaluate the techno-economic prospects of present and future production routes of bio-based bulk chemicals produced with WB. Current and future technology routes are evaluated for 15 products assuming prices of fermentable sugar between 70 euro/t and 400 euro/t and crude oil prices of US $25/barrel and US $50/barrel. The results are compared to current technology routes of petrochemical equivalents. For current state-of-the-art WB processes and a crude oil price of US $25/barrel, WB-based ethanol, 1,3-propanediol, polytrimethylene terephthalate and succinic acid are economically viable. Only three WB products are economically not viable for future technology: acetic acid, ethylene and PLA. Future-technology ethylene and PLA become economically viable for a higher crude oil price (US $50/barrel). Production costs plus profits of WB products decrease by 20-50% when changing from current to future technology for a crude oil price of US $25 per barrel and across all sugar prices. Technological progress in WB can thus contribute significantly to improved economic viability of WB products. A large-scale introduction of WB-based production of economically viable bulk chemicals would therefore be desirable if the environmental impacts are smaller than those of current petrochemical production routes.


Assuntos
Biotecnologia/métodos , Biotecnologia/tendências , Indústria Química/tendências , Biotecnologia/economia , Carboidratos/química , Carboidratos/economia , Indústria Química/economia , Fermentação , Petróleo/classificação , Petróleo/economia , Ácidos Ftálicos/química , Ácidos Ftálicos/economia , Propilenoglicóis/química , Propilenoglicóis/economia , Ácido Succínico/química , Ácido Succínico/economia
13.
Appl Biochem Biotechnol ; 121-124: 807-19, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15930560

RESUMO

In recent years, the concept of producing biodiesel from renewable lipid sources has regained international attention. In Brazil, a national program was launched in 2002 to evaluate the technical, economic, and environmental competitiveness of biodiesel in relation to the commercially available diesel oil. Several research projects were initiated nationwide to investigate and/or optimize biodiesel production from renewable lipid sources and ethanol derived from sugarcane (ethyl esters). Once implemented, this program will not only decrease our dependence on petroleum derivatives but also create new market opportunities for agribusiness, opening new jobs in the countryside, improving the sustainability of our energy matrix, and helping the Brazilian government to support important actions against poverty. This article discusses the efforts to develop the Brazilian biodiesel program in the context of technical specifications as well as potential oilseed sources.


Assuntos
Biotecnologia/economia , Biotecnologia/métodos , Carboidratos/economia , Fontes Geradoras de Energia/economia , Etanol/economia , Gasolina , Saccharum , Biotecnologia/instrumentação , Biotecnologia/tendências , Brasil , Celulose/economia , Gasolina/economia
14.
Appl Biochem Biotechnol ; 121-124: 59-70, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15917587

RESUMO

Brazil is one of the world's largest producers of alcohol from biomass at low cost and is responsible for more than 1 million direct jobs. In 1973, the Brazilian Program of Alcohol (Proalcool) stimulated the creation of a bioethanol industry that has led to large economic, social, and scientific improvements. In the year 1984, 94.5% of Brazil's cars used bioethanol as fuel. In 2003/2004, 350.3 million of sugarcane produced 24.2 million t of sugar and 14.4 billion L of ethanol for an average 4.3 million cars using ethanol. Since its inception, cumulative investment in Proalcool totals US$11 billion, and Brazil has saved US$27 billion in oil imports. The ethanol production industry from sugarcane gene-rates 152 times more jobs than would have been the case if the same amount of fuel was produced from petroleum, and the use of ethanol as a fuel is advantageous for environmental reasons. In 2003, one of the biggest Brazilian ethanol industries started consuming 50% of the residual sugarcane bagasse to produce electrical energy (60 MW), a new alternative use of bioenergy for the Brazilian market. Other technologies for commercial uses of bagasse are in development, such as in the production of natural fibers, sweeteners (glucose and xylitol), single-cell proteins, lactic acid, microbial enzymes, and many other products based on fermentations (submerged and semisolid). Furthermore, studies aimed at the increase in the biosynthesis of sucrose and, consequently, ethanol productivity are being conducted to understand the genetics of sugarcane. Although, at present, there remain technical obstacles to the economic use of some ethanol industry residues, several research projects have been carried out and useful data generated. Efficient utilization of ethanol industry residues has created new opportunities for new value-added products, especially in Brazil, where they are produced in high quantities.


Assuntos
Biotecnologia/economia , Biotecnologia/métodos , Carboidratos/economia , Celulose/economia , Fontes Geradoras de Energia/economia , Etanol/economia , Saccharum , Biotecnologia/instrumentação , Biotecnologia/tendências , Brasil , Gasolina/economia
15.
Bioresour Technol ; 96(9): 985-1002, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15668196

RESUMO

Reducing the use of non-renewable fossil energy reserves together with improving the environment are two important reasons that drive interest in the use of bioethanol as an automotive fuel. Conversion of sugar and starch to ethanol has been proven at an industrial scale in Brazil and the United States, respectively, and this alcohol has been able to compete with conventional gasoline due to various incentives. In this paper, we examined making ethanol from the sugar extracted from the juice of sweet sorghum and/or from the hemicellulose and cellulose in the residual sorghum bagasse versus selling the sugar from the juice or burning the bagasse to make electricity in four scenarios in the context of North China. In general terms, the production of ethanol from the hemicellulose and cellulose in bagasse was more favorable than burning it to make power, but the relative merits of making ethanol or sugar from the juice was very sensitive to the price of sugar in China. This result was confirmed by both process economics and analysis of opportunity costs. Thus, a flexible plant capable of making both sugar and fuel-ethanol from the juice is recommended. Overall, ethanol production from sorghum bagasse appears very favorable, but other agricultural residues such as corn stover and rice hulls would likely provide a more attractive feedstock for making ethanol in the medium and long term due to their extensive availability in North China and their independence from other markets. Furthermore, the process for residue conversion was based on particular design assumptions, and other technologies could enhance competitiveness while considerations such as perceived risk could impede applications.


Assuntos
Carboidratos/biossíntese , Carboidratos/economia , Fontes Geradoras de Energia/economia , Etanol/economia , Etanol/metabolismo , Sorghum/metabolismo , Reatores Biológicos/economia , Indústria Química/economia , China , Simulação por Computador , Conservação dos Recursos Naturais , Análise Custo-Benefício/métodos , Metabolismo Energético , Microbiologia Industrial/economia , Modelos Econométricos
16.
Crit Rev Biotechnol ; 23(2): 149-73, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12889744

RESUMO

Carbohydrates are the potential biomolecules derived from nature. Their molecular diversity has led to a bewildering variety of species, structures and characteristics all performing a large array of functions of great significance. Biologically they are vital as message (immunological) carriers, physiologically they are useful as energy (nutritional) reserves, and technologically they are needed for altering the texture and consistency (functional) of foods. Recent advances in glycobiology have opened up a new understanding of the role of sugars in biology and medicine. Noncellulosic beta-(1-3)-linked D-glucans, a group of polysaccharides found as constituents of fungi, algae, and higher plants, exhibit many interesting properties, depending on their molecular conformation. They are excellent 'biological response modifiers' and show significant immunomodulatory activities. They elicit a variety of host defense biological responses, for example, potent antitumor activity. On the other hand, the mixed-linkage ((1-3/1-4)-beta-linked) glucans are important constituents of cereal cell walls, where they perform properties of physiological importance, such as water holding capacity, porosity, and plasticity, which are useful at different stages of growth/development of plants. Of late, carbohydrate-based therapeutics are becoming the promise against many chronic diseases of today and tomorrow. Some of the characteristic features, structural attributes, functional significance, and applications of a selected few carbohydrate species are the subject matter of this review.


Assuntos
Biotecnologia/métodos , Metabolismo dos Carboidratos , Carboidratos/química , Conservação dos Recursos Naturais , Indústria Farmacêutica/métodos , Tecnologia de Alimentos/métodos , Biotecnologia/economia , Biotecnologia/tendências , Carboidratos/economia , Carboidratos/uso terapêutico , Indústria Farmacêutica/economia , Tecnologia de Alimentos/economia , Tecnologia de Alimentos/tendências , Glucanos/química , Glucanos/economia , Glucanos/metabolismo , Glucanos/uso terapêutico , Glucose/química , Glucose/economia , Glucose/metabolismo , Glucose/uso terapêutico , Polissacarídeos/química , Polissacarídeos/economia , Polissacarídeos/metabolismo , Polissacarídeos/uso terapêutico , Amido/química , Amido/economia , Amido/metabolismo , Amido/uso terapêutico
17.
Biotechnol Prog ; 19(2): 254-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12675557

RESUMO

Lignocellulosic biomass such as agricultural and forestry residues and dedicated crops provides a low-cost and uniquely sustainable resource for production of many organic fuels and chemicals that can reduce greenhouse gas emissions, enhance energy security, improve the economy, dispose of problematic solid wastes, and improve air quality. A technoeconomic analysis of biologically processing lignocellulosics to ethanol is adapted to project the cost of making sugar intermediates for producing a range of such products, and sugar costs are predicted to drop with plant size as a result of economies of scale that outweigh increased biomass transport costs for facilities processing less than about 10,000 dry tons per day. Criteria are then reviewed for identifying promising chemicals in addition to fuel ethanol to make from these low cost cellulosic sugars. It is found that the large market for ethanol makes it possible to achieve economies of scale that reduce sugar costs, and coproducing chemicals promises greater profit margins or lower production costs for a given return on investment. Additionally, power can be sold at low prices without a significant impact on the selling price of sugars. However, manufacture of multiple products introduces additional technical, marketing, risk, scale-up, and other challenges that must be considered in refining of lignocellulosics.


Assuntos
Reatores Biológicos/economia , Carboidratos/economia , Celulose/economia , Celulose/metabolismo , Conservação dos Recursos Naturais/economia , Análise Custo-Benefício/métodos , Fontes Geradoras de Energia/economia , Etanol/economia , Biomassa , Carboidratos/biossíntese , Etanol/metabolismo , Lignina/economia , Lignina/metabolismo , Estados Unidos
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