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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.
Int J Biol Macromol ; 155: 315-323, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32224183

RESUMO

Klebsiella pneumoniae strain KPB-1 was isolated in early 2011 from the pleural fluid of an inpatient admitted at an Italian hospital. It was characterized to produce the KPC-3 carbapenemase and to belong to sequence type 512, a derivative of sequence type 258 clade II characterized by the cps-2 gene cluster. The K-antigen of K. pneumoniae KPB-1 was purified and its structure determined by using GLC-MS of appropriate carbohydrate derivatives and 1D and 2D NMR spectroscopy of the native polysaccharide. All the collected data demonstrated the following repeating unit for the K. pneumoniae KPB-1 capsular polysaccharide: The reactions catalysed by each glycosyltransferase in the cps-2 gene cluster were assigned on the basis of structural homology with other Klebsiella K antigens.


Assuntos
Cápsulas Bacterianas/química , Proteínas de Bactérias/metabolismo , Glicosiltransferases/metabolismo , Klebsiella pneumoniae/enzimologia , Polissacarídeos Bacterianos/química , beta-Lactamases/metabolismo , Proteínas de Bactérias/economia , Proteínas de Bactérias/genética , Glicosiltransferases/genética , Klebsiella pneumoniae/química , Klebsiella pneumoniae/genética , Família Multigênica , beta-Lactamases/economia
3.
Appl Biochem Biotechnol ; 189(4): 1108-1126, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31168707

RESUMO

In order to recover biomolecules, a single downstream processing step is carried out. In this sense, an aqueous two-phase system (ATPS) containing polyethylene glycol (PEG) and potassium phosphate salts is used. Intending the purification of Burkholderia cepacia (Bc) lipase, the effects of the molecular masses of 1500 (PEG 1500), 4000 (PEG 4000), and 6000 (PEG 6000), pH (6, 7, and 8) and distinct tie line lengths are perfomed. Although this is reasonable reported in literature, a study covering an economical production aspect considering the Bc is scarce. This characterizes a novelty proposed in this investigation. Lipase is recovered in a polymer phase at lower pH value. PEG 1500/phosphate salt ATPS at pH 6 is considered a good method with ~ 98% of the extraction efficiency. Another contribution of this proposed investigation concerns to a biotechnological material synthesis, which is applied in several advanced and revolutionize engineering practices. Additionally, an economic analysis of the proposed method indicates a minimal sale price (~ US$410/L) inducing to a future and potential commercial application.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Burkholderia cepacia/enzimologia , Lipase/química , Lipase/isolamento & purificação , Proteínas de Bactérias/economia , Concentração de Íons de Hidrogênio , Lipase/economia , Polietilenoglicóis/química
4.
Int J Food Sci Nutr ; 65(1): 53-61, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24020495

RESUMO

The aim of this study was to characterize potential probiotic strain co-producing α-amylase and ß-galactosidase. Sixty-three strains, isolated from pickle samples were screened for their hydrolase producing capacity by utilizing different starches as carbon source. One out of 63 strains, isolated from traditionally fermented pickled yam showing maximum hydrolase activity (α-amylase (36.9 U/ml) and ß-galactosidase (42.6 U/ml)) within a period of 48 hours was identified as Lactococcus lactis subsp. lactis. Further, it was assessed for the probiotic characteristics under gastrointestinal conditions like acidic, alkaline, proteolytic enzymes, bile stress and found to exhibit tolerance to these stresses. The therapeutic potential of the isolate is implicated because of its antagonistic effect against enteric foodborne pathogens (Salmonella typhimurium, Escherichia coli 0157:H7, Staphylococcus aureus, Yersinia enterocolitica and Aeromonas hydrophila). The results of this study entail a potential applicability of the isolate in developing future probiotic foods besides the production of industrially significant hydrolases.


Assuntos
Dioscorea/microbiologia , Alimentos em Conserva/microbiologia , Lactococcus lactis/enzimologia , Tubérculos/microbiologia , Probióticos/metabolismo , alfa-Amilases/metabolismo , beta-Galactosidase/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/economia , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Dieta/etnologia , Digestão , Dioscorea/química , Farmacorresistência Bacteriana Múltipla , Alimentos em Conserva/economia , Indústria de Processamento de Alimentos/economia , Suco Gástrico/microbiologia , Índia , Resíduos Industriais/economia , Lactococcus lactis/efeitos dos fármacos , Lactococcus lactis/crescimento & desenvolvimento , Lactococcus lactis/isolamento & purificação , Interações Microbianas , Viabilidade Microbiana , Suco Pancreático/microbiologia , Tubérculos/química , Probióticos/economia , Probióticos/isolamento & purificação , Amido/economia , Amido/metabolismo , alfa-Amilases/economia , alfa-Amilases/isolamento & purificação , beta-Galactosidase/economia , beta-Galactosidase/isolamento & purificação
5.
Appl Microbiol Biotechnol ; 97(23): 9931-40, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24121933

RESUMO

Keratinases are well-recognized enzymes with the unique ability to attack highly cross-linked, recalcitrant structural proteins such as keratin. Their potential in environmental clean-up of huge amount of feather waste has been well established since long. Today, they have gained importance in various other biotechnological and pharmaceutical applications. However, commercial availability of keratinases is still limited. Hence, to attract entrepreneurs, investors and enzyme industries it is utmost important to explicitly present the market potential of keratinases through detailed account of its application sectors. Here, the application areas have been divided into three parts: the first one is dealing with the area of exclusive applications, the second emphasizes protease dominated sectors where keratinases would prove better substitutes, and the third deals with upcoming newer areas which still await practical documentation. An account of benefits of keratinase usage, existing market size, and available commercial sources and products has also been presented.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/economia , Microbiologia Industrial/economia , Peptídeo Hidrolases/economia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo
6.
J Med Econ ; 15(1): 61-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22026590

RESUMO

OBJECTIVE: The spectrum of diseases caused by Streptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi) represents a large burden on healthcare systems around the world. Meningitis, bacteraemia, community-acquired pneumonia (CAP), and acute otitis media (AOM) are vaccine-preventable infectious diseases that can have severe consequences. The health economic model presented here is intended to estimate the clinical and economic impact of vaccinating birth cohorts in Canada and the UK with the 10-valent, pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) compared with the newly licensed 13-valent pneumococcal conjugate vaccine (PCV-13). METHODS: The model described herein is a Markov cohort model built to simulate the epidemiological burden of pneumococcal- and NTHi-related diseases within birth cohorts in the UK and Canada. Base-case assumptions include estimates of vaccine efficacy and NTHi infection rates that are based on published literature. RESULTS: The model predicts that the two vaccines will provide a broadly similar impact on all-cause invasive disease and CAP under base-case assumptions. However, PHiD-CV is expected to provide a substantially greater reduction in AOM compared with PCV-13, offering additional savings of Canadian $9.0 million and £4.9 million in discounted direct medical costs in Canada and the UK, respectively. LIMITATIONS: The main limitations of the study are the difficulties in modelling indirect vaccine effects (herd effect and serotype replacement), the absence of PHiD-CV- and PCV-13-specific efficacy data and a lack of comprehensive NTHi surveillance data. Additional limitations relate to the fact that the transmission dynamics of pneumococcal serotypes have not been modelled, nor has antibiotic resistance been accounted for in this paper. CONCLUSION: This cost-effectiveness analysis suggests that, in Canada and the UK, PHiD-CV's potential to protect against NTHi infections could provide a greater impact on overall disease burden than the additional serotypes contained in PCV-13.


Assuntos
Proteínas de Bactérias/economia , Proteínas de Transporte/economia , Imunoglobulina D/economia , Lipoproteínas/economia , Vacinas Conjugadas/economia , Adolescente , Adulto , Idoso , Proteínas de Bactérias/uso terapêutico , Canadá , Proteínas de Transporte/uso terapêutico , Criança , Pré-Escolar , Análise Custo-Benefício , Humanos , Imunoglobulina D/uso terapêutico , Lipoproteínas/uso terapêutico , Cadeias de Markov , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Reino Unido , Vacinas Conjugadas/uso terapêutico , Adulto Jovem
7.
Plant Biotechnol J ; 9(3): 283-300, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21375687

RESUMO

Bacillus thuringiensis (Bt) is a soil bacterium that forms spores during the stationary phase of its growth cycle. The spores contain crystals, predominantly comprising one or more Cry and/or Cyt proteins (also known as δ-endotoxins) that have potent and specific insecticidal activity. Different strains of Bt produce different types of toxin, each of which affects a narrow taxonomic group of insects. Therefore, Bt toxins have been used as topical pesticides to protect crops, and more recently the proteins have been expressed in transgenic plants to confer inherent pest resistance. Bt transgenic crops have been overwhelmingly successful and beneficial, leading to higher yields and reducing the use of chemical pesticides and fossil fuels. However, their deployment has attracted some criticism particularly with regard to the potential evolution of pest-resistant insect strains. Here, we review recent progress in the development of Bt technology and the countermeasures that have been introduced to prevent the evolution of resistant insect populations.


Assuntos
Bacillus thuringiensis/química , Controle Biológico de Vetores/economia , Pesquisa , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Proteínas de Bactérias/economia , Biotecnologia , Endotoxinas/química , Endotoxinas/economia , Proteínas Hemolisinas/química , Proteínas Hemolisinas/economia , Controle de Mosquitos , Plantas Geneticamente Modificadas
8.
Lancet ; 351(9114): 1472-6, 1998 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-9605803

RESUMO

BACKGROUND: The cost of Haemophilus influenzae type b (Hib) conjugate vaccines has limited their use in non-industrialised countries. To identify more economical vaccination schedules, we carried out a randomised trial of the immunogenicity of alternative regimens to the standard three-dose series. METHODS: 627 Chilean infants were randomly allocated to one of four regimens with either Hib polysaccharide-tetanus toxoid conjugate vaccine (PRP-T) or Hib oligosaccharide-diphtheria mutant toxoid conjugate vaccine (PRP-CRM197), for a total of eight groups. All infants receive diphtheria-tetanus-pertussis (DTP) vaccine at ages 2, 4, and 6 months. The regimens included three full doses, three fractional doses consisting of one half or one third of the full dose, and a regimen of two full doses (at age 4 and 6 months). The primary outcome was the proportion of infants with serum anti-polyribosylribitol phosphate (PRP, the type b capsular polysaccharide) concentrations of 0.15 microg/mL or more at age 8 months. FINDINGS: 93% (95% CI 85-98) of infants vaccinated with three full doses of PRP-T or PRP-CRM197 (95% CI 84-98) achieved anti-PRP concentrations of 0.15 microg/mL or more at age 8 months, compared with 91% (83-96) to 100% (95-100) of infants immunised with any fractional-dose regimen. Of the infants vaccinated with two doses of PRP-T or PRP-CRM197, 99% (93-100) and 87% (77-93) developed anti-PRP concentrations of 0.15 microg/mL or more, respectively. INTERPRETATION: 91% (83-96) to 100% (95-100) of infants immunised with one-half or one-third of a full dose of Hib conjugate developed protective antibody concentrations. Carrier priming with DTP may make two-dose schedules an option in some places. These alternative regimens could bring the cost of Hib vaccines within reach of countries that currently cannot afford them.


Assuntos
Proteínas de Bactérias/administração & dosagem , Infecções por Haemophilus/prevenção & controle , Vacinas Anti-Haemophilus/administração & dosagem , Haemophilus influenzae tipo b , Toxoide Tetânico/administração & dosagem , Vacinação/economia , Proteínas de Bactérias/economia , Chile/epidemiologia , Custos e Análise de Custo , Países em Desenvolvimento , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Relação Dose-Resposta Imunológica , Infecções por Haemophilus/epidemiologia , Vacinas Anti-Haemophilus/economia , Humanos , Esquemas de Imunização , Lactente , Toxoide Tetânico/economia , Vacinas Combinadas/administração & dosagem , Vacinas Conjugadas , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/economia
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