Production of heterologous cutinases by E. coli and improved enzyme formulation for application on plastic degradation

Background: The hydrolytic action of cutinases has been applied to the degradation of plastics. Polyethylene terephthalate (PET) have long half-life which constitutes a major problem for their treatment as urban solid residues. The aim of this work was to characterize and to improve stable the enzyme to optimize the process of degradation using enzymatic hydrolysis of PET by recombinant cutinases. Results: The wild type form of cutinase from Fusarium solani pisi and its C-terminal fusion to cellulose binding domain N1 from Cellulomonas fimi were produced by genetically modified Escherichia coli. The maximum activity of cutinases produced in Lactose Broth in the presence of ampicillin and isopropyl β- D-1-thiogalactopyranoside (IPTG) was 1.4 IU/mL. Both cutinases had an optimum pH around 7.0 and they were stable between 30 and 50ºC during 90 min. The addition of glycerol, PEG-200 and (NH4)2SO4 to the metabolic liquid, concentrated by ultra filtration, stabilized the activity during 60 days at 28ºC. The treatment of PET with cutinases during 48 hrs led to maxima weight loss of 0.90%. Conclusions: Recombinant microbial cutinases may present advantages in the treatment of poly(ethylene terephthalate) PET through enzymatic treatments.This research study was financially supported by CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior), FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco) and CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)

Production and stability studies of the bioemulsifier obtained from a new strain of Candida glabrata UCP 1002

Evaluation of both tenso-active and emulsifying activities indicated that a biosurfactant was produced by the newly isolated and promising strain Candida glabrata isolated from mangrove sediments. The extracellular water-soluble emulsifying agent was isolated and identified as a heteropolymer. The maximum of bioemulsifier production was observed when the strain was grown on soluble and insoluble substrates cotton seed oil plus glucose, reaching values of 10.0 g/l after 144 hrs at 200 rpm. The cell-free culture broth containing the examined agent lowered the surface tension of the medium to 31 mN/m. Stable and compact emulsions with emulsifying activity of 75% of cotton seed oil were detected. The emulsification capacity remained practically unaltered within a wide pH (2-12), temperature (4-80\ub0C) ranges and under NaCl concentrations up to 10%

PRODUÇÃO DE PROTEASE UTILIZANDO DIFERENTES MEIOS ATRAVÉS DE AMOSTRAS DE BACILLUS LICHENIFORMIS ISOLADAS DO PORTO DA CIDADE DE RECIFE - PERNAMBUCO

A utilização de novas amostras de micro-organismos para produção de enzimas microbianas por processos fermentativos tem aumentado nas últimas décadas. As proteases são enzimas que apresentam uma alta especificidade catalítica, pois atuam principalmente na hidrólise de proteínas e de peptídeos. O gênero Bacillus se destaca por produzir uma grande quantidade de produtos biotecnológicos de alto valor agregado. Foram realizados ensaios para avaliar o potencial de 3 amostras de B. licheniformis (UCP 1010, 1020 e 1022) isoladas do Porto da cidade do Recife, Pernambuco, Brasil, através de uma seleção da produção de protease em meio sólido utilizando diferentes temperaturas (28, 37, 45 e 50oC). Após a seleção da amostra com maior potencial de produção de protease, foram realizados ensaios de produção da enzima através de fermentação submersa utilizando 3 diferentes meios, 150 rpm, 37 oC, durante 72 h. Os resultados revelaram que a amostra UCP 1020 obteve o maior halo característico de produção enzimática (3,5 cm) na temperatura de 37oC, durante 96 h. A produção através da fermentação submersa revelou que o meio denominado de 3 apresentou a maior atividade enzimática obtida (30,45 U L-1).AbstractThe use of new samples of microorganisms for the production of microbial enzymes by fermentation processes has increased in recent decades. Proteases are enzymes which exhibit a high catalytic specificity because they act primarily on the hydrolysis of proteins and peptids. The genus Bacillus stands for producing a lot of biotechnological products with high added value. Assays were performed to evaluate the potential of 3 samples of B. licheniformis (UCP 1009, 1020 and 1022) isolated from the Port of Recife, Pernambuco, Brazil, through a protease production of selection on solid medium using different temperatures (28 37, 45 and 50 °C). After the selection of the sample with higher protease production potential, production of the enzyme assays were performed by submerged fermentation using 3 different medium. The performace assays in 150 rpm, 37 ° C, 72 h. The results revealed that the CPU 1020 sample had the highest enzyme production characteristic halo (3.5 cm) at 37°C temperature for 96 h. The production by submerged fermentation revealed that the medium called presented an enzymatic activity of 30.45 U L -1

Characterization and properties of the biosurfactant produced by Candida lipolytica UCP 0988

Background: Biotechnological processes are costly, especially for the production of biosurfactants. The successful production of a biosurfactant is dependent on the development of processes using low cost raw materials. Considering the importance of the characteristics of a biosurfactant to facilitate its industrial application, the properties of the biosurfactant produced by Candida lipolytica through previously optimized medium have been established. Results: The yeast was grown for 72 h to determine the kinetics of growth and production. The surface tension of the cell-free broth was reduced from 55 to 25 mN/m. The yield of biosurfactant was 8.0 g/l with a CMC of 0.03%. The biosurfactant was characterized as an anionic lipopeptide composed of 50% protein, 20% lipids, and 8% of carbohydrates. Conclusions: The isolated biosurfactant showed no toxicity against different vegetable seeds: Brassica oleracea, Solanum gilo and Lactuca sativa L. and the micro-crustacean Artemia salina. The properties of the biosurfactant produced suggest its potential application in industries that require the use of effective compounds at low cost

Chromium (VI) ion adsorption features of chitosan film and its chitosan/zeolite conjugate 13X film

This research evaluated the importance of the adsorption properties of chitosan a chitosan/zeolite conjugate film for the removal of Cr(VI) ions from solutions in the 5–260 mg/L concentration range, when the pH was adjusted to 4.0 and 6.0. The uptake capacities of the films formed by chitosan and by the chitosan/zeolite conjugate were calculated by mass balance. The equilibrium isotherms were fitted to the Langmuir, Freundlich and Redlich-Peterson models. The chitosan film seems to be a good sorbent for Cr(VI) at pH 4, but its physical instability suggests the need for a more resilient support. Due to this fact zeolite was added to the chitosan matrix in solution and a chitosan/zeolite (CS/Zeo) film was thus formed. The solubility of the film and the characterization of the different matrices by FTIR, TGA and X-Ray showed that a cross-linked structure was formed between the chitosan and zeolite and the solubility of the film increased. In this study, the low manufacturing cost of the CS/Zeo matrix, the good uptake of Cr(VI) at acidic pH (17.28 mg/g) and the non desorption of Cr(VI) from the film in water suggests this combination should be tested in industrial environment.The authors are grateful for the Coordination of Improvement of Higher Education Personnel (CAPES - Brazil) for PhD fellowship and the financial support received from Financier of Studies and Projects (FINEP - Brazil), National Council for Scientific and Technological Development (CNPq - Brazil), Catholic University of Pernambuco (UNICAP - Brazil), University of Minho (UMINHO - Portugal). They also acknowledge Antonio Soares Vicente (UMINHO - Portugal) who kindly supplied the chitosan

Optimization and evaluation of biosurfactant produced by Pantoea sp. using pineapple peel residue, vegetable fat and corn steep liquor

In this study, the authors have investigated the potential of a bacterial strain of Pantoea sp., isolated from wastewater of the textile industry, for the production of biosurfactant. The biosurfactant production was optimized by the combination of CCD (central composite design) and RSM (response surface methodology). To assess the effects and interactions of medium the vegetable fat (1.5, 2.0 and 2.5 v/v), the variables corn steep liquor (2.0, 5.0 and 8.0 v/v) and pineapple peel residue (10.0, 25.0 and 40.0 v/v) on the surface tension were evaluated. The empirical model developed through RSM in terms of the effective operational factors mentioned above was found to be adequate to describe the biosurfactant production. Compositional analysis of the produced biosurfactant has been carried out by FT-IR (Fourier transform infrared spectoscopy) and subjected to the test of removing hydrocarbons. Through the analysis, vegetable fat and pineapple peel residue were found to be the most significant factors, whereas corn steep liquor had less effect within the ranges investigated. A maximum reduction in surface tension of 30.00 mN/m was obtained under the optimal conditions of 2.0% (v/v) vegetable fat concentration, 5.0% (v/v) corn steep liquor and 25.0% (v/v) pineapple peel residue concentration of medium. FT-IR spectrometer analysis of the biosurfactant characterized it as a glycolipid derivative. The biosurfactant exhibited the ability to solubilize the hydrocarbons tested, working between 64% and 92%. According to consists of bars with a length proportional to the absolute value of the estimated effects divided by the standard error. On this chart, ANOVA (analysis of variance) effect estimates are arranged from the largest to smallest absolute value. The chart includes a vertical line at the critical p-value of 0.05. Effects for which the bars are smaller than the critical p-value are considered non-significant and do not have an effect on the response variables. The effects are either positive or negative ANOVA; the determination of regression coefficients and the construction of graphs were performed using the Statistical® program, version 7.0 (Statsoft Inc, RSA). The results, the biosurfactant produced by Pantoea sp. can be a valuable source for application in rapid environmental bioremediation9269279CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À CIÊNCIA E TECNOLOGIA DO ESTADO DE PERNAMBUCO - FACEPEsem informaçã