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1.
Int J Biol Macromol ; 170: 94-106, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33358950

RESUMO

Considering the need of new lactic acid bacteria (LAB) for the production of novel biosurfactant (BS) molecules, the current study brings out a new insight on the exploration of cheese samples for BS producers and process optimization for industrial applications. In view of this, Lactobacillus plantarum 60FHE, Lactobacillus paracasei 75FHE, and Lactobacillus paracasei 77FHE were selected as the most operative strains. The biosurfactants (BSs) described as glycolipoproteins via Fourier-transform infrared spectroscopy (FTIR) exhibited antimicrobial activity against the food-borne pathogens. L. plantarum 60FHE BS showed an anticancer activity against colon carcinoma cells and had a week antiviral activity against Hepatitis A virus. Furthermore, glycolipoprotein production was enhanced by 1.42-fold through the development of an optimized process using central composite design (CCD). Emulsifying activities were stable after 60-min incubation from 4 to 120 °C, at pH 2-12, and after the addition of NaCl (2-14%). Characterization by nuclear magnetic resonance spectroscopy (1H NMR) revealed that BS produced from strain 60FHE was glycolipoprotein. L. plantarum produced mixed BSs determined by Liquid Chromatography/Mass Spectrometry (LC-MS). Thus, indicating that BS was applied as a microbial food prevention and biomedical. Also, L. plantarum 60FHE BS was achieved with the use of statistical optimization on inexpensive food wastes.


Assuntos
Anti-Infecciosos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Queijo/microbiologia , Glicoproteínas/isolamento & purificação , Lactobacillus plantarum/química , Lipoproteínas/isolamento & purificação , Tensoativos/isolamento & purificação , Anti-Infecciosos/química , Anti-Infecciosos/economia , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/economia , Antineoplásicos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/economia , Proteínas de Bactérias/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida , Neoplasias do Colo/patologia , Glicoproteínas/química , Glicoproteínas/economia , Glicoproteínas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Vírus da Hepatite A/efeitos dos fármacos , Humanos , Lacticaseibacillus paracasei/química , Lacticaseibacillus paracasei/isolamento & purificação , Lactobacillus plantarum/isolamento & purificação , Lipoproteínas/química , Lipoproteínas/economia , Lipoproteínas/farmacologia , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Filogenia , Ribotipagem , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química , Tensoativos/economia , Tensoativos/farmacologia , Resíduos/análise
2.
Appl Microbiol Biotechnol ; 103(21-22): 8647-8656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31515599

RESUMO

In 1968, Arima et al. discovered the heptapeptide, known as surfactin, which belongs to a family of lipopeptides. Known for its ability to reduce surface tension, it also has biological activities such as antimicrobial and antiviral. Its non-ribosomal synthesis mechanism was later discovered (1991). Lipopeptides represent an important class of surfactants, which can be applied in many industrial sectors such as food, pharmaceutical, agrochemicals, detergents, and cleaning products. Currently, 75% of the surfactants used in the various industrial sectors are from the petrochemical industry. Nevertheless, there are global current demands (green chemistry concept) to replace the petrochemical products with environmentally friendly products, such as surfactants by biosurfactants. The production biosurfactants still are costly. Thus, an alternative to reduce the production costs is using agro-industrial waste as a culture medium associated with an efficient and scalable purification process. This review puts a light on the agro-industrial residues used to produce surfactin and the techniques used for its recovery.


Assuntos
Microbiologia Industrial/economia , Lipopeptídeos/economia , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/economia , Peptídeos Cíclicos/metabolismo , Tensoativos/economia , Bactérias/genética , Bactérias/metabolismo , História do Século XX , História do Século XXI , Microbiologia Industrial/história , Microbiologia Industrial/métodos , Lipopeptídeos/genética , Lipopeptídeos/história , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/história , Tensoativos/história , Tensoativos/metabolismo
3.
Eur J Med Chem ; 182: 111639, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470306

RESUMO

Amphiphilic kanamycins bearing hydrophobic modifications at the 6″ position have attracted interest due to remarkable antibacterial-to-antifungal switches in bioactivity. In this report, we investigate a hurdle that hinders practical applications of these amphiphilic kanamycins: a cost-effective synthesis that allows the incorporation of various connecting functionalities to which the hydrophobic moieties are connected to the kanamycin core. A cost-effective tosylation enables various modifications at the 6″ position, which is scalable to a 90-g scale. The connecting functionalities, such as amine and thiol, were not the dominant factor for biological activity. Instead, the linear chain length played the decisive role. Amphiphilic kanamycin attached with tetradecyl (C14) or hexadecyl (C16) showed strong antifungal and modest antibacterial activities than with shorter chains (C6-C10). However, increases in chain length were closely correlated with an increase in HeLa cell toxicity. Thus, a compromise between the antimicrobial activities and cytotoxicities, for optimal efficacy of amphiphilic kanamycins may contain chain lengths between C8 and C12. Finally, the described synthetic protocol also allows the preparation of a fluorescent amphiphilic kanamycin selective toward fungi.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Canamicina/farmacologia , Tensoativos/farmacologia , Antibacterianos/química , Antibacterianos/economia , Antifúngicos/química , Antifúngicos/economia , Sobrevivência Celular/efeitos dos fármacos , Análise Custo-Benefício , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Canamicina/química , Canamicina/economia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tensoativos/química , Tensoativos/economia
4.
Colloids Surf B Biointerfaces ; 182: 110358, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325779

RESUMO

In this study, rhamnolipid (RL) production by Pseudomonas aeruginosa SS14 utilizing rice based Distillers Dried Grains with Solubles (rDDGS) as the sole carbon source was evaluated and the production parameters were optimized using response surface methodology. Highest RL (RL-rDDGS) yield was 14.87 g/L in a culture medium containing 12% (w/v) rDDGS and 11% (v/v) inoculum concentration after 48 h of fermentation at 35 °C. RL-rDDGS was produced as a mixture of mono and di-RL congeners with four novel homologues Rha-C18:2, Rha-C19, Rha-C9, and Rha-Rha-C19. The RL reduced the surface tension of water to 34.8 mN/m at a critical micelle concentration (CMC) value of 100 mg/L, exhibited high stability at a wide range of pH (6-12), heating time (0-120 min), and salinity (2-12% NaCl). Furthermore, RL-rDDGS demonstrated appreciable biofilm disruptive property against Candida tropicalis. This is the first report on the usage of rDDGS for sustainable and low cost production of RL.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Glicolipídeos/farmacologia , Oryza/química , Tensoativos/farmacologia , Antifúngicos/economia , Antifúngicos/isolamento & purificação , Antifúngicos/metabolismo , Biofilmes/crescimento & desenvolvimento , Candida tropicalis/crescimento & desenvolvimento , Estabilidade de Medicamentos , Análise Fatorial , Fermentação , Glicolipídeos/biossíntese , Glicolipídeos/economia , Glicolipídeos/isolamento & purificação , Temperatura Alta , Concentração de Íons de Hidrogênio , Micelas , Testes de Sensibilidade Microbiana , Oryza/metabolismo , Pseudomonas aeruginosa , Salinidade , Sementes/química , Sementes/metabolismo , Tensão Superficial , Tensoativos/economia , Tensoativos/isolamento & purificação , Tensoativos/metabolismo , Água/química
5.
J Appl Microbiol ; 126(1): 2-13, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30066414

RESUMO

Biosurfactants are economically most sought after biotechnological compounds of the 21st century. However, inefficient bioprocessing has mitigated the economical commercial production of these compounds. Although much work is being done on the use of low-cost substrates for their production, a paucity of literature exists on the upcoming bioprocess optimization strategies and their successes and potential for economical biosurfactant production. This review discusses some of the latest developments and most promising strategies to enhance and economize the biosurfactant production process. Recent market analysis, developments in the field of optimally formulated cost credit substrates for enhanced product formation and subsequent process economization are few of the critical aspects highlighted here. Use of nanoparticles and coproduction of biosurfactant along with other commercially important compounds like enzymes, are other upcoming bioprocess intensification strategies. The recent developments discussed here would not only give an overview of pertinent parameters for economic biosurfactant production but would also bring to fore multiple strategies that would open up new avenues of research on biosurfactant production. This would go a long way in making biosurfactants a commercially successful compound of the current century.


Assuntos
Bactérias/metabolismo , Microbiologia Industrial , Tensoativos/metabolismo , Bactérias/genética , Microbiologia Industrial/economia , Microbiologia Industrial/métodos , Tensoativos/química , Tensoativos/economia
6.
Biotechnol Appl Biochem ; 65(4): 523-532, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29297935

RESUMO

Since 60-80% of total costs of production are usually associated with downstream collection, separation, and purification processes, it has become advantageous to investigate how to replace traditional methods with efficient and cost-effective alternative techniques for recovery and purification of biosurfactants. In the traditional techniques, large volumes of organic solvents are usually used for increasing production cost and the overall environmental burden. In addition, traditional production and separation methods typically carried out in batch cultures reduce biosurfactant yields due to product inhibition and lower biosurfactants activity as a result of interaction with the organic solvents used. However, some in situ recovery methods that allow continuous separation of bioproducts from culture broth leading to an improvement in yield production and fermentation efficiency. For biosurfactants commercialization, enhancement of product capacity of the separation methods and the rate of product removal is critical. Recently, interest in the integration of separation methods with a production step as rapid and efficient techniques has been increasing. This review focuses on the technology gains and potentials for the most common methods used in in situ product removal: foam fractionation and ultrafiltration, especially used to recover and purify two well-known biosurfactants: glycolipids (rhamnolipids) and lipopeptides (surfactins).


Assuntos
Glicolipídeos/economia , Lipopeptídeos/economia , Tensoativos/economia , Glicolipídeos/isolamento & purificação , Glicolipídeos/metabolismo , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/metabolismo , Solventes/economia , Solventes/isolamento & purificação , Solventes/metabolismo , Tensoativos/isolamento & purificação , Tensoativos/metabolismo
8.
J Sci Food Agric ; 96(13): 4310-20, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27098847

RESUMO

Glycolipids, consisting of a carbohydrate moiety linked to fatty acids, are microbial surface active compounds produced by various microorganisms. They are characterized by high structural diversity and have the ability to decrease the surface and interfacial tension at the surface and interface, respectively. Rhamnolipids, trehalolipids, mannosylerythritol lipids and cellobiose lipids are among the most popular glycolipids. They have received much practical attention as biopesticides for controlling plant diseases and protecting stored products. As a result of their antifungal activity towards phytopathogenic fungi and larvicidal and mosquitocidal potencies, glycolipid biosurfactants permit the preservation of plants and plant crops from pest invasion. Also, as a result of their emulsifying and antibacterial activities, glycolipids have great potential as food additives and food preservatives. Furthermore, the valorization of food byproducts via the production of glycolipid biosurfactant has received much attention because it permits the bioconversion of byproducts on valuable compounds and decreases the cost of production. Generally, the use of glycolipids in many fields requires their retention from fermentation media. Accordingly, different strategies have been developed to extract and purify glycolipids. © 2016 Society of Chemical Industry.


Assuntos
Agroquímicos/química , Agentes de Controle Biológico/química , Aditivos Alimentares/química , Glicolipídeos/química , Resíduos Industriais/análise , Tensoativos/química , Agroquímicos/economia , Agroquímicos/isolamento & purificação , Agroquímicos/metabolismo , Animais , Biodegradação Ambiental , Agentes de Controle Biológico/economia , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/metabolismo , Fenômenos Químicos , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/imunologia , Fermentação , Aditivos Alimentares/economia , Aditivos Alimentares/isolamento & purificação , Aditivos Alimentares/metabolismo , Conservantes de Alimentos/química , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Conservantes de Alimentos/metabolismo , Indústria de Processamento de Alimentos/economia , Fungos/química , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Glicolipídeos/economia , Glicolipídeos/isolamento & purificação , Glicolipídeos/metabolismo , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/química , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/metabolismo , Humanos , Resíduos Industriais/economia , Praguicidas/química , Praguicidas/economia , Praguicidas/isolamento & purificação , Praguicidas/metabolismo , Imunidade Vegetal/efeitos dos fármacos , Tensoativos/economia , Tensoativos/isolamento & purificação , Tensoativos/metabolismo
9.
Int J Mol Sci ; 16(8): 17101-59, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26225963

RESUMO

The global bio-based chemical market is growing in size and importance. Bio-based solvents such as glycerol and 2-methyltetrahydrofuran are often discussed as important introductions to the conventional repertoire of solvents. However adoption of new innovations by industry is typically slow. Therefore it might be anticipated that neoteric solvent systems (e.g., ionic liquids) will remain niche, while renewable routes to historically established solvents will continue to grow in importance. This review discusses bio-based solvents from the perspective of their production, identifying suitable feedstocks, platform molecules, and relevant product streams for the sustainable manufacturing of conventional solvents.


Assuntos
Biocombustíveis , Recuperação e Remediação Ambiental/métodos , Química Verde/métodos , Solventes/efeitos adversos , Solventes/química , Solventes/economia , Tensoativos/efeitos adversos , Tensoativos/química , Tensoativos/economia
10.
J Biosci Bioeng ; 120(5): 526-31, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25865657

RESUMO

Being eco-friendly, less toxic, more biodegradable and biocompatible, biological surfactants have higher activity and stability compared to synthetic ones. In spite of the fact that there are abundant benefits of biosurfactants over the synthetic congeners, the problem related with the economical and large scale production proceeds. The utilization of several industrial wastes in the production media as substrates reduces the production cost. This current study aims optimization of biosurfactant production conditions by Pleurotus djamor, grown on sunflower seed shell, grape wastes or potato peels as renewable cheap substrates in solid state fermentation. After determination of the best substrate for biosurfactant production, we indicate optimum size and amount of solid substrate, volume of medium, temperature, pH and Fe(2+) concentrations on biosurfactant production. In optimum conditions, by reducing water surface tension to 28.82 ± 0.3 mN/m and having oil displacement diameter of 3.9 ± 0.3 cm, 10.205 ± 0.5 g/l biosurfactant was produced. Moreover, chemical composition of biosurfactant produced in optimum condition was determined by FTIR. Lastly, laboratory's large-scale production was carried out in optimum conditions in a tray bioreactor designed by us and 8.9 ± 0.5 g/l biosurfactant was produced with a significant surface activity (37.74 ± 0.3 mN/m). With its economical suggestions and applicability of laboratory's large-scale production, this work indicates the possibility of using low cost agro-industrial wastes as renewable substrates for biosurfactant production. Therefore, using economically produced biosurfactant will reduce cost in several applications such as bioremediation, oil recovery and biodegradation of toxic chemicals.


Assuntos
Reatores Biológicos , Fermentação , Pleurotus/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Reatores Biológicos/economia , Cátions Bivalentes , Indústria Alimentícia , Helianthus , Concentração de Íons de Hidrogênio , Resíduos Industriais/economia , Ferro , Sementes , Solanum tuberosum , Tensão Superficial , Tensoativos/economia , Temperatura , Vitis , Água
11.
J Agric Food Chem ; 59(17): 9443-7, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21797277

RESUMO

The utilization of biosurfactants for the bioremediation of contaminated soil is not yet well established, because of the high production cost of biosurfactants. Consequently, it is interesting to look for new biosurfactants that can be produced at a large scale, and it can be employed for the bioremediation of contaminated sites. In this work, biosurfactants from Lactobacillus pentosus growing in hemicellulosic sugars solutions, with a similar composition of sugars found in trimming vine shoot hydrolysates, were employed in the bioremediation of soil contaminated with octane. It was observed that the presence of biosurfactant from L. pentosus accelerated the biodegradation of octane in soil. After 15 days of treatment, biosurfactants from L. pentosus reduced the concentration of octane in the soil to 58.6 and 62.8%, for soil charged with 700 and 70,000 mg/kg of hydrocarbon, respectively, whereas after 30 days of treatment, 76% of octane in soil was biodegraded in both cases. In the absence of biosurfactant and after 15 days of incubation, only 1.2 and 24% of octane was biodegraded in soil charged with 700 and 70,000 mg/kg of octane, respectively. Thus, the use of biosurfactants from L. pentosus, as part of a well-designed bioremediation process, can provide mechanisms to mobilize the target contaminants from the soil surface to make them more available to the microbial population.


Assuntos
Biodegradação Ambiental , Lactobacillus/metabolismo , Octanos/química , Poluentes do Solo/química , Tensoativos/química , Tensoativos/metabolismo , Fenômenos Químicos , Descontaminação/métodos , Octanos/análise , Solo/química , Poluentes do Solo/análise , Tensoativos/economia
12.
J Wound Ostomy Continence Nurs ; 37(1): 46-51, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20075692

RESUMO

PURPOSE: A decision model was developed in a pilot study comparing a regimen using a skin care product line containing active ingredients and nutrients with a commercially available alternative skin care regimen in an elderly convalescent care hospital-based center. METHODS: Using a decision-tree model, skin treatment with a nutrient-based skin care (NBSC) formulation was compared with products without nutrients. The number of skin-tear-free days was the primary outcome measure. A cost-effectiveness ratio was calculated for each skin treatment as the average cost for reaching a particular outcome. Incidence of skin tear data was collected from residents in a convalescent center from 2004 to 2005. An independent t test was used to compare differences in the number of skin tears between periods when NBSC and other formulations were used. All costs in the decision model were adjusted to 2007 dollars. Sensitivity analysis was used to test uncertain data. RESULTS: The NBSC provided more skin-tear-free days and was less costly than the use of non-NBSC products. The expected skin-tear-free days for a patient in the model treated with NBSC were 179.7 days compared with 154.6 days for non-NBSC products, yielding an incremental effect of 25.1 days. The expected cost of preventing skin tears and treatment via skin treatment per patient in the NBSC group was $281.00 versus $324.10 for periods when other products were used. CONCLUSION: The NBSC had a lower projected cost for prevention of skin tears and more skin-tear-free days when compared with non-NBSC products.


Assuntos
Suplementos Nutricionais/economia , Hospitais de Convalescentes , Lacerações/epidemiologia , Lacerações/prevenção & controle , Higiene da Pele/economia , Pele/lesões , Idoso , Estudos de Coortes , Análise Custo-Benefício , Árvores de Decisões , Humanos , Incidência , Fosfolipídeos/economia , Fosfolipídeos/uso terapêutico , Estudos Retrospectivos , Tensoativos/economia , Tensoativos/uso terapêutico
13.
Mar Biotechnol (NY) ; 11(5): 551-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19034398

RESUMO

Preliminary characterization of a biosurfactant-producing Azotobacter chroococcum isolated from marine environment showed maximum biomass and biosurfactant production at 120 and 132 h, respectively, at pH 8.0, 38 degrees C, and 30 per thousand salinity utilizing a 2% carbon substrate. It grew and produced biosurfactant on crude oil, waste motor lubricant oil, and peanut oil cake. Peanut oil cake gave the highest biosurfactant production (4.6 mg/mL) under fermentation conditions. The biosurfactant product emulsified waste motor lubricant oil, crude oil, diesel, kerosene, naphthalene, anthracene, and xylene. Preliminary characterization of the biosurfactant using biochemical, Fourier transform infrared spectroscopy, and mass spectral analysis indicated that the biosurfactant was a lipopeptide with percentage lipid and protein proportion of 31.3:68.7.


Assuntos
Azotobacter/fisiologia , Microbiologia Ambiental , Tensoativos/metabolismo , Azotobacter/crescimento & desenvolvimento , Azotobacter/metabolismo , Concentração de Íons de Hidrogênio , Biologia Marinha , Óleo de Amendoim , Petróleo/metabolismo , Óleos de Plantas/metabolismo , Salinidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química , Tensoativos/economia , Temperatura , Fatores de Tempo
14.
Trends Biotechnol ; 24(11): 509-15, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16997405

RESUMO

Biosurfactants or microbial surfactants are surface-active biomolecules that are produced by a variety of microorganisms. Biosurfactants have gained importance in the fields of enhanced oil recovery, environmental bioremediation, food processing and pharmaceuticals owing to their unique properties--higher biodegradability, lower toxicity, and effectiveness at extremes of temperature, pH and salinity. However, large-scale production of these molecules has not been realized because of low yields in production processes and high recovery and purification costs. This article describes some practical approaches that have been adopted to make the biosurfactant production process economically attractive: these include the use of cheaper raw materials, optimized and efficient bioprocesses and overproducing mutant and recombinant strains for obtaining maximum productivity. The application of these strategies in biosurfactant production processes, particularly those using hyper-producing recombinant strains in the optimally controlled environment of a bioreactor, might lead towards the successful commercial production of these valuable and versatile biomolecules in near future.


Assuntos
Bactérias/metabolismo , Candida/metabolismo , Tensoativos/metabolismo , Animais , Bactérias/genética , Biodegradação Ambiental , Candida/genética , Laticínios/microbiologia , Fermentação , Indústria Alimentícia , Resíduos Industriais , Mutação , Óleos de Plantas/metabolismo , Amido/metabolismo , Tensoativos/química , Tensoativos/economia
15.
Biotechnol Prog ; 22(2): 547-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16599575

RESUMO

Highly efficient separation and purification of polyhydroxyalkanoates (PHAs) from PHA-containing cell mass is essential to production of the bioplastics from renewable resources in a cost-effective, environmentally friendly way. Based on selective dissolution of non-PHA cell mass (NPCM) by protons in aqueous solution and crystallization kinetics of PHA biopolymers, a simple process is developed and demonstrated to recover PHAs from cell mass to high purity (>97 wt %) with high yield (>95 wt %). The average molecular weight of biopolyesters is controlled, which follows an exponential function of process severity, a combined factor of processing conditions. Compared with conventional chemical treatment such as sequential surfactant and hypochlorite treatment, this new technology substantially reduces the chemical cost for PHA recovery and purification from PHA-containing cell mass.


Assuntos
Alcenos/química , Alcenos/isolamento & purificação , Álcalis , Alcenos/metabolismo , Biopolímeros/biossíntese , Biopolímeros/química , Biopolímeros/isolamento & purificação , Cristalização , Cupriavidus necator/química , Cupriavidus necator/metabolismo , Hidroxibutiratos/química , Peso Molecular , Poliésteres/química , Proteínas/química , Prótons , Soluções/economia , Espectrofotometria Infravermelho , Tensoativos/economia
16.
J Wound Ostomy Continence Nurs ; 32(3): 163-70, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15931146

RESUMO

This study compared clinical outcomes and nursing labor costs associated with (a) balsam Peru, hydrogenated castor oil, and trypsin (BCT) ointment; (b) BCT + Other; and (c) Other treatments in 2014 wound episodes occurring in 861 patients (mean 2.34 wounds/patient). Treatment with BCT ointment or BCT + Other was associated with a higher healing rate (P < .05). No Stage 1 or 2 ulcer treated with BCT ointment progressed, compared with 13.8% treated with BCT + Other and 13.4% treated with Other. The reported mean duration of treatment and time to heal were shorter for ulcers treated with BCT ointment, but differences did not reach significance, possibly because of the variability in reported treatment times. Mean daily nursing labor costs were lower for treatment with BCT than Other ($50.8 vs $61.7, P < .05). These data suggest that treatment of Stage 1 or 2 ulcers with BCT may be associated with shorter treatment time and time to heal and a potential reduction in treatment-related nursing labor costs.


Assuntos
Bálsamos/uso terapêutico , Óleo de Rícino/análogos & derivados , Úlcera por Pressão/terapia , Higiene da Pele , Tensoativos/uso terapêutico , Tripsina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Bálsamos/economia , Óleo de Rícino/economia , Óleo de Rícino/uso terapêutico , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Feminino , Custos de Cuidados de Saúde , Humanos , Assistência de Longa Duração/economia , Assistência de Longa Duração/métodos , Masculino , Pessoa de Meia-Idade , Pesquisa em Administração de Enfermagem , Pesquisa em Avaliação de Enfermagem , Casas de Saúde , Recursos Humanos de Enfermagem/economia , Úlcera por Pressão/economia , Estudos Retrospectivos , Higiene da Pele/economia , Higiene da Pele/métodos , Higiene da Pele/enfermagem , Tensoativos/economia , Estudos de Tempo e Movimento , Resultado do Tratamento , Tripsina/economia , Estados Unidos , Carga de Trabalho/economia , Cicatrização
17.
Ecotoxicol Environ Saf ; 61(1): 44-52, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15814309

RESUMO

Chemical dispersants enhance oil spill dispersion by forming water-accommodated micelles with oil droplets. However, how dispersants alter bioavailability and subsequent bioaccumulation of hydrocarbons is not well understood. Thus, the goal was to investigate the influence of a chemical dispersant on the disposition (uptake, biotransformation, and depuration) of a model hydrocarbon, [14C]-phenanthrene ([14C]PHN), by larval topsmelt (Atherinops affinis). Exposure was via aqueous-only or combined dietary and aqueous routes from a water-accommodated fraction (WAF) of Prudhoe Bay Crude Oil (PBCO) or a WAF of Corexit 9527-dispersed PBCO (DO). Trophic transfer was measured by incorporating into exposure media both a rotifer (Brachionus plicatilis) as food for the fish and a phytoplankton (Isochrysis galbana) as food for the rotifers. Short-term (4 h) bioconcentration of PHN was significantly decreased in topsmelt when oil was treated with dispersant (P < 0.05), but differences diminished after 12 h. When trophic transfer was incorporated, PHN accumulation was initially delayed but after 12 h attained similar levels. Dispersant use also significantly decreased the proportion of biotransformed PHN (as 9-phenanthrylsulfate) produced by topsmelt (P < 0.05). However, overall PHN depuration was not affected by dispersant use. Thus, chemical dispersant use in oil spill response may reduce short-term uptake but not long-term accumulation of hydrocarbons such as PHN in pelagic fish.


Assuntos
Osmeriformes/metabolismo , Fenantrenos/metabolismo , Gestão da Segurança , Tensoativos/farmacologia , Algoritmos , Animais , Biotransformação , Análise Custo-Benefício , Dieta , Eucariotos/metabolismo , Cadeia Alimentar , Hidrocarbonetos Aromáticos/metabolismo , Larva/metabolismo , Petróleo , Fenantrenos/farmacocinética , Rotíferos/metabolismo , Gestão da Segurança/economia , Água do Mar/análise , Tensoativos/economia
19.
Biotechnol Prog ; 18(6): 1277-81, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12467462

RESUMO

This study was aimed at the development of economical methods for higher yields of biosurfactant by suggesting the use of low-cost raw materials. Two oil-degrading strains, Pseudomonas aeruginosa GS9-119 and DS10-129, were used to optimize a substrate for maximum rhamnolipid production. Among the two strains, the latter produced maxima of 4.31, 2.98, and 1.77 g/L rhamnolipid biosurfactant using soybean oil, safflower oil, and glycerol, respectively. The yield of biosurfactant steadily increased even after the bacterial cultures reached the stationary phase of growth. Characterization of rhamnolipids using mass spectrometry revealed the presence of dirhamnolipids (Rha-Rha-C(10)-C(10)). Emulsification activity of the rhamnolipid biosurfactant produced by P. aeruginosa DS10-129 was greater than 70% using all the hydrocarbons tested, including xylene, benzene, hexane, crude oil, kerosene, gasoline, and diesel. P. aeruginosa GS9-119 emulsified only hexane and kerosene to that level.


Assuntos
Glicolipídeos/biossíntese , Pseudomonas aeruginosa/metabolismo , Emulsões , Glicerol/metabolismo , Glicolipídeos/química , Glicolipídeos/economia , Hidrocarbonetos , Espectrometria de Massas , Pseudomonas aeruginosa/química , Óleo de Cártamo/metabolismo , Óleo de Soja/metabolismo , Tensoativos/economia
20.
Int J Dermatol ; 39(7): 515-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10940115

RESUMO

BACKGROUND: Poison ivy (toxicodendron) dermatitis is the most common allergic contact dermatitis in the USA. No studies have shown an effect of washing after a short period of time for the prevention of binding of urushiol to the skin. Objective To evaluate the efficacy of three different modes of postcontact prevention using a surfactant (Dial ultra dishwashing soap), an oil-removing compound (Goop), and chemical inactivation (a commercial product Tecnu). METHODS: A consented, unsponsored, volunteer experimental study on medical students from the University of Missouri School of Medicine, Kansas City. Each subject served as his/her own control, comparing four 2.5-cm exposed squares on the inner aspect of the forearm, three of which were treated and one untreated. RESULTS: Comparisons between the different agents were nonsignificant with P > 0.05. Each treatment, however, was significantly improved over the untreated control. CONCLUSIONS: Our study showed 70%, 61.8%, and 56. 4% protection with Tecnu, Goop, and Dial, respectively, when compared to the positive control, or to the possible maximum response, with a cost per ounce (in a local drug and automotive store) of $1.25, $0.07, and $0.07, respectively, for a decrease in protection that is nonsignificant.


Assuntos
Dermatite por Toxicodendron/prevenção & controle , Solventes/economia , Solventes/uso terapêutico , Tensoativos/economia , Tensoativos/uso terapêutico , Adulto , Análise Custo-Benefício , Feminino , Antebraço , Humanos , Masculino , Valores de Referência , Resultado do Tratamento , Estados Unidos
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