Relationship between galactomannan structure and physicochemical properties of films produced thereof.

In this work five sources of galactomannans, Adenanthera pavonina, Cyamopsis tetragonolobus, Caesalpinia pulcherrima, Ceratonia siliqua and Sophora japonica, presenting mannose/galactose ratios of 1.3, 1.7, 2.9, 3.4 and 5.6, respectively, were used to produce galactomannan-based films. These films were characterized in terms of: water vapour, oxygen and carbon dioxide permeabilities (WVP, O 2 P and CO 2 P); moisture content, water solubility, contact angle, elongation-at-break (EB), tensile strength (TS) and glass transition temperature (T g ). Results showed that films properties vary according to the galactomannan source (different galactose distribution) and their mannose/galactose ratio. Water affinity of mannan and galactose chains and the intermolecular interactions of mannose backbone should also be considered being factors that affect films' properties. This work has shown that knowing mannose/galactose ratio of galactomannans is possible to foresee galactomannan-based edible films properties.

Carboxyl ester hydrolase from Penicillium expansum: cloning, characterization and overproduction by Penicillium griseoroseum.

AIMS: In this study, a gene that encodes a carboxylesterase (carb) in Penicillium expansum GF was cloned, sequenced and overexpressed by Penicillium griseoroseum PG63, and the enzyme was characterized. METHODS AND RESULTS: The recombinant strain, P. griseoroseum T55, obtained upon transformation using the plasmid pAN-52-1-carb, showed integration of the carb gene into at least two heterologous sites of the genome by Southern blotting. Furthermore, the recombinant strain T55 exhibited almost a fourfold increase in carboxylesterase activity compared with PG63 strain when both were cultured without inducers. Based on the secondary structure and multiple sequence alignments with carboxylesterases, cholinesterase and lipase, a three-dimensional model was obtained. The α/ß barrel topology, that is typical of esterases and lipases, was indicated for the CARB protein with Ser(213)-Glu(341)-His(456) as the putative catalytic triad. CARB preferentially hydrolysed acyl chains with eight carbon atoms, and its activity was optimal at a pH of 7·0 and a temperature of 25°C. CARB exhibited stability in alkaline pH, high activity under mesophilic conditions and stability in organic solvents. CONCLUSION: The CARB protein is potentially useful in bioremediation, food and chemical/pharmaceutical industries. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to report the development of a recombinant strain superproducing a Penicillium sp. carboxylesterase.

Integral valorisation of tomato by-products towards bioactive compounds recovery: Human health benefits.

The tomato processing industry is one of the world's most important markets. This industry aims to optimise production, minimise energy costs and waste streams while ensuring high-quality products. This sector produces substantial amounts of by-products frequently disposed of as waste rather than reintroducing them with a new intent into the supply chain. However, these by-products are rich in bioactive compounds (BC), including carotenoids, fibre, which exhibit antioxidant, anti-inflammatory and chemopreventive properties, and cardiovascular protection. Reusing these compounds is favourable to reducing the environmental impact and enables the development of added-value products with various possible uses such as food and feed additives, nutraceuticals, cosmeceuticals, etc. This review summarises relevant issues towards the recovery and valorisation of BC from industrial tomato by-products within a circular economy context.

A novel antimicrobial lectin from Eugenia malaccensis that stimulates cutaneous healing in mice model.

OBJECTIVE: The present work reports the purification and partial characterization of an antibacterial lectin (EmaL) obtained from Eugenia malaccensis seeds as well as the evaluation of its effect in the daily topical treatment of repairing process of cutaneous wounds in mice. MATERIALS AND METHODS: The cutaneous wound was produced by the incision of the skin and use of lectin in the treatment of mice cutaneous wounds was evaluated. Surgical wounds were treated daily with a topical administration of EmaL and parameters such as edema, hyperemia, scab, granulation and scar tissues as well as contraction of wounds were analyzed. RESULTS: A novel lectin, with a molecular mass of 14 kDa, was isolated from E. malaccensis using affinity chromatography. The lectin (EmaL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes; the lectin-induced rabbit erythrocyte agglutination was inhibited by glucose, casein, ovalbumin and fetuin. Also, Emal was very effective in the inhibition of bacterial growth, with the best inhibition results obtained for Staphylococcus aureus. Inflammatory signals such as edema and hyperemia were statistically less intense when EmaL was applied compared to the control. The histopathological analysis showed that the treated injured tissue presented reepithelialization (complete or partial) and areas of transition more evidenced than those of the control group, especially due to well organized pattern of collagen fibers presented in the granulation fibrous tissue. CONCLUSION: Presented results are a preliminary indication of the pharmacological interest in using EmaL as antimicrobial agent and in the repairing process of cutaneous wounds.

Improved pectinase production in Penicillium griseoroseum recombinant strains.

AIMS: To obtain recombinant strains of Penicillium griseoroseum that produce high levels of pectin lyase (PL) and polygalacturonase (PG) simultaneously. METHODS AND RESULTS: A strain with high production of PL was transformed with the plasmid pAN52pgg2, containing the gene encoding PG of P. griseoroseum, under control of the gpd promoter gene from Aspergillus nidulans. Southern blot analysis demonstrated that all strain had at least one copy of pAN52pgg2 integrated into the genome. The recombinant strain P. griseoroseum T20 produced levels of PL and PG that were 266- and 27-fold greater, respectively, than the wild-type strain. Furthermore, the extracellular protein profile of recombinant T20 showed two protein bands of c. 36 and 38 kDa, associated with PL and PG, respectively. CONCLUSIONS: This recombinant strain T20 produces PL and PG using carbon sources of low costs, and an enzyme preparation that is free of cellulolytic and proteolytic activities. SIGNIFICANCE AND IMPACT OF THE STUDY: PL and PG play an important role in the degradation of pectin. Owing to their use in the juice and wines industries, there is a growing interest in the inexpensive production of these enzymes. This work describes an efficient system of protein expression and secretion using the fungus P. griseoroseum.

The effect of bovine milk lactoferrin on human breast cancer cell lines.

The evidence that biologically active food components are key environmental factors affecting the incidence of many chronic diseases is overwhelming. However, the full extent of such components in our diet is unknown, as is our understanding of their mechanisms of action. Beyond the interaction of these food components with the gut and intestinal immune functions, whey proteins such as lactoferrin are being tested as anticancer agents. Lactoferrin is an iron-binding protein that has been reported to inhibit several types of cancer. In the present work, the effects of bovine milk lactoferrin on human breast cancer HS578T and T47D cells were studied. The cells were either untreated or treated with lactoferrin concentrations ranging from 0.125 to 125 µM. Lactoferrin decreased the cell viability of HS578T and T47D by 47 and 54%, respectively, and increased apoptosis about 2-fold for both cell lines. Proliferation rates decreased by 40.3 and 63.9% for HS578T and T47D, respectively. For the T47D line, cell migration decreased in the presence of the protein. Although the mechanisms of action are not fully known, the results gathered in this work suggest that lactoferrin interferes with some of the most important steps involved in cancer development.

Antimicrobial and antiadhesive properties of a biosurfactant isolated from Lactobacillus paracasei ssp. paracasei A20.

AIMS: The aim of this study was to determine the antimicrobial and antiadhesive properties of a biosurfactant isolated from Lactobacillus paracasei ssp. paracasei A20 against several micro-organisms, including Gram-positive and Gram-negative bacteria, yeasts and filamentous fungi. METHODS AND RESULTS: Antimicrobial and antiadhesive activities were determined using the microdilution method in 96-well culture plates. The biosurfactant showed antimicrobial activity against all the micro-organisms assayed, and for twelve of the eighteen micro-organisms (including the pathogenic Candida albicans, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus agalactiae), the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were achieved for biosurfactant concentrations between 25 and 50 mg ml(-1). Furthermore, the biosurfactant showed antiadhesive activity against most of the micro-organisms evaluated. CONCLUSIONS: As far as we know, this is the first compilation of data on antimicrobial and antiadhesive activities of biosurfactants obtained from lactobacilli against such a broad group of micro-organisms. Although the antiadhesive activity of biosurfactants isolated from lactic acid bacteria has been widely reported, their antimicrobial activity is quite unusual and has been described only in a few strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained in this study regarding the antimicrobial and antiadhesive properties of this biosurfactant opens future prospects for its use against micro-organisms responsible for diseases and infections in the urinary, vaginal and gastrointestinal tracts, as well as in the skin, making it a suitable alternative to conventional antibiotics.

Understanding decidual vasculopathy and the link to preeclampsia: A review.

Preeclampsia is the archetype of a spectrum of clinical disorders related to abnormal placental development or function, characterized by placental histological lesions. Among those lesions, decidual vasculopathy is a term used to describe lesions of maternal spiral arteries, which are encountered on placental examination in about half of the women with preeclampsia. The morphological features of the lesions include perivascular lymphocytic infiltration, fibrinoid necrosis and foam cell incorporation within the vessel wall. Due to the resemblance of the latter characteristic to atherosclerosis, they are alternatively termed acute atherosis. Decidual vasculopathy correlates with worse maternal and neonatal outcomes, as well as placental pathology. In this article, we review the available literature on decidual vasculopathy and address the pitfalls in histological analysis of the lesions, including the varying definitions of the lesions and sample collection methods. We also discuss the current evidence on the etiology of the lesions and propose a novel hypothesis linking the three etiological pathways to the formation of decidual vasculopathy and, ultimately, the emergence of the heterogeneous group of placental dysfunction disorders, known as the great obstetric syndromes.

beta-Fructofuranosidase production by repeated batch fermentation with immobilized Aspergillus japonicus.

The fungus Aspergillus japonicus ATCC 20236 was immobilized in vegetal fiber and used in repeated batch fermentations of sucrose (200 g/l) for the production of beta-fructofuranosidases (FFase). The assays were performed during eight consecutive cycles that were completed in a total period of 216 h. After each 24-h cycle of fermentation (except for the first cycle, which lasted 48 h), the fermented broth was replaced by fresh medium, and the FFase activity was determined in the replaced medium. The average value of FFase activity was a constant 40.6 U/ml at the end of the initial seven cycles, but had decreased by 22% at the end of the eighth cycle. Concurrent with these high and constant FFase values, the hydrolyzing activity of this enzyme increased during the cycles, while the transfructosylating activity decreased. As a consequence, the maximum production of fructooligosaccharides of 134.60 g/l observed in the initial 30 h of fermentation (first cycle) had gradually decreased by the end of the subsequent cycles, reaching approximately 23% of this value during cycles 4-8. Based on these results, we conclude that the present immobilization system has a great potential for application in a semi-continuous process for the production of FFase, but further studies are necessary to maintain the FFase transfructosylation activity at high levels during the overall process.

The Systems Biology of Lateral Root Formation: Connecting the Dots.

The root system is a major determinant of a plant's access to water and nutrients. The architecture of the root system to a large extent depends on the repeated formation of new lateral roots. In this review, we discuss lateral root development from a systems biology perspective. We focus on studies combining experiments with computational modeling that have advanced our understanding of how the auxin-centered regulatory modules involved in different stages of lateral root development exert their specific functions. Moreover, we discuss how these regulatory networks may enable robust transitions from one developmental stage to the next, a subject that thus far has received limited attention. In addition, we analyze how environmental factors impinge on these modules, and the different manners in which these environmental signals are being integrated to enable coordinated developmental decision making. Finally, we provide some suggestions for extending current models of lateral root development to incorporate multiple processes and stages. Only through more comprehensive models we can fully elucidate the cooperative effects of multiple processes on later root formation, and how one stage drives the transition to the next.

Purification of a lectin from Eugenia uniflora L. seeds and its potential antibacterial activity.

AIMS: The aim of this work was to analyse the antimicrobial properties of a purified lectin from Eugenia uniflora L. seeds. METHODS AND RESULTS: The E. uniflora lectin (EuniSL) was isolated from the seed extract and purified by ion-exchange chromatography in DEAE-Sephadex with a purification factor of 11.68. The purified lectin showed a single band on denaturing electrophoresis, with a molecular mass of 67 kDa. EuniSL agglutinated rabbit and human erythrocytes with a higher specificity for rabbit erythrocytes. The haemagglutination was not inhibited by the tested carbohydrates but glycoproteins exerted a strong inhibitory action. The lectin proved to be thermo resistant with the highest stability at pH 6.5 and divalent ions did not affect its activity. EuniSL demonstrated a remarkable nonselective antibacterial activity. EuniSL strongly inhibited the growth of Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella sp. with a minimum inhibitory concentration (MIC) of 1.5 microg ml(-1), and moderately inhibited the growth of Bacillus subtilis, Streptococcus sp. and Escherichia coli with a MIC of 16.5 microg ml(-1). CONCLUSIONS: EuniSL was found to be effective against bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: The strong antibacterial activity of the studied lectin indicates a high potential for clinical microbiology and therapeutic applications.

One-step co-culture fermentation strategy to produce high-content fructo-oligosaccharides.

An integrated process enabling the simultaneous production and purification of fructo-oligosaccharides (FOS) was explored. A co-culture fermentation with Aspergillus ibericus (used as FOS producer strain) and Saccharomyces cerevisiae YIL162 W (for small saccharides removal) was optimized. Inoculation conditions of S. cerevisiae, fermentative broth composition, temperature and pH were optimized by experimental design. Yeast extract concentration and temperature were the most significant variables affecting FOS purity. Co-culture fermentations with simultaneously inoculation of the strains, run under 30 °C, initial pH 6.0 and 17 g L-1 yeast extract led to FOS mixtures with 97.4 ± 0.2% (w/w) purity. The fermentations conducted in bioreactor, at a 0.8 vvm aeration rate, yielded 0.70 ± 0.00 gFOS.ginitial GF-1 at 45 h fermentation, with a FOS content of 133.7 ± 0.1 g L-1. A purity of FOS up to 93.8 ± 0.7% (w/w) was achieved. The one-step fermentation proved to be efficient, economical and fast.

Strategies for the production of high-content fructo-oligosaccharides through the removal of small saccharides by co-culture or successive fermentation with yeast.

Fructo-oligosaccharides (FOS) obtained by fermentation of sucrose may be purified at large-scale by continuous chromatography (Simulated Moving Bed: SMB). In order to improve the efficiency of the subsequent SMB purification, the optimization of the fermentative broth composition in salts and sugars was investigated. Fermentations conducted at reduced amount of salts, using Aureobasidium pullulans whole cells, yielded 0.63 ± 0.03 g of FOS per gram of initial sucrose. Additionally, a microbial treatment was proposed to reduce the amount of small saccharides in the mixture. Two approaches were evaluated, namely a co-culture of A. pullulans with Saccharomyces cerevisiae; and a two-step fermentation in which FOS were first synthesized by A. pullulans and then the small saccharides were metabolized by S. cerevisiae. Assays were performed in 100mL shaken flasks and further scaled-up to a 3 L working volume bioreactor. Fermentations in two-step were found to be more efficient than the co-culture ones. FOS were obtained with a purity of 81.6 ± 0.8% (w/w), on a dry weight basis, after the second-step fermentation with S. cerevisiae. The sucrose amount was reduced from 13.5 to 5.4% in total sugars, which suggests that FOS from this culture broth will be more efficiently separated by SMB.

Metabolic profile and cardiovascular risk in a population of renal transplant recipients.

INTRODUCTION: Cardiovascular disease is more common in renal transplant recipients (RTRs) than in the general population, and is the major cause of both graft loss and patient death in RTRs. OBJECTIVES: This study aimed to characterize the cardiovascular risk factors, calculate the 7-year risk for major adverse cardiac events and the 7-year risk for death in a population of RTRs using a cardiovascular risk calculator, and determine the main cardiovascular risk factors associated with increased prediction of major adverse cardiac event (MACE) and death. PATIENTS: This is a retrospective review of clinical data from 121 RTRs who are in follow-up programs at our institution, and who had a functioning and stable graft for longer than 6 months. RESULTS: Among 121 adult patients followed at our institution (59.5% males, mean age of 49.6 ± 13.8 years, mean times for functioning grafts were 105 ± 73.5 mo), 86.8% had hypertension, 19.8% had diabetes, 24.8% were current or former smokers, 61.9% had increased body mass index, and 71% had dyslipidemia. The 7-year risk for MACE was more than 10% in 38 (31.4%) patients with age, diabetes, and smoke being independent risk predictors. The 7-year risk for death was more than 10% in 56 (46.3%) patients with age, diabetes, blood pressure, smoking, and male gender being independent risk predictors. CONCLUSION: There is a high prevalence of cardiovascular risk factors in a population of RTRs, and there is increased risk for MACE and death. Accurate risk prediction is important for physician decision support and patient education, promoting improved cardiovascular health of RTRs, and thus prolonging the survival of both patients and graft.

An alternative technique for creating the gastrojejunostomy in laparoscopic Roux-en-Y gastric bypass: experience with 28 consecutive patients.

BACKGROUND: This study illustrates our experience in laparoscopic Roux-en-Y gastric bypass (LRYGBP) using a new technique for creating the gastro-jejunostomy. METHODS: Between April and November 1999, 28 patients underwent LRYGBP. In the first 10 patients the transoral route with endoscopic guidance was utilized for placement of the anvil in the gastric pouch. A new totally intra-peritoneal approach was utilized in the next 18 patients, avoiding the trans-oral route. RESULTS: There were 23 women and 5 men with an average age of 36 years (range 24-51). The mean BMI was 47, with range 41-64. Of the patients, 82% had one or more associated co-morbid conditions (hypertension, diabetes, sleep apnea, arthritis). Average operative time in the first 10 patients using the trans-oral route with endoscopic guidance was 340 minutes (range 240-390 min). The next 18 patients underwent totally intra-peritoneal anvil placement with a 240-minute average operating time (range 150-310 min). There were no open conversions or mortalities. There were 4 complications, including 2 wound infections, one urinary tract infection, and one intra-abdominal abscess. The two wound infections occurred in the first 10 patients that underwent trans-oral introduction of the anvil. CONCLUSIONS: LRYGBP was a safe and feasible operation. We believe that our technique is easily reproducible, avoiding the trans-oral route for introducing the anvil. This technique may also decrease operative time and possibly the incidence of wound infections, although we are still in the learning curve and final conclusions cannot be made.

Immobilized particles in gel matrix-type porous media. Homogeneous porous media model.

Diffusion in pure gels and gels with immobilized cells was analyzed. A model of diffusion assuming a homogeneous cell distribution in gel was improved by introducing a tortuosity value. By theoretical analysis and numerical modeling it was shown that the tortuosity of a gel with immobilized cells is the product of two factors: (1) tortuosity generated by the cells, Tc, and (2) tortuosity of the gel matrix, Tg, both variables being a function of cell volume fraction, phi(c). Total tortuosity is thus T(Sigma) = TcTg. On the basis of this approach, it was possible to analyze diffusivity data for gels with immobilized cells. It was shown that, in these systems, the diffusivity eta = D(e)/D(0) is a complex function of (1) diffusivity in the gel, eta(g), and (2) diffusivity in immobilized cells, eta(c). The developed model allowed for the description of the dependence of D(e)/D(0) on phi(c). Comparison with numerous published experimental data showed a good fit. Observed deviations might be explained by nonhomogeneous cell distributions inside the gel matrix.

Evaluation of crude hydroxypropyl starch as a bioseparation aqueous-phase-forming polymer.

A new aqueous two-phase system based on crude hydroxypropyl starch (HPS) and poly(ethylene glycol) (PEG) is described. Unlike other polymer-polymer aqueous two-phase systems, the HPS used is commercially available. Previous works have characterized almost exclusively purified carbohydrates or their derivatives, having neglected the large amount of gums and carbohydrates already used in the paper, food, or textile industries. Two-phase aqueous polymer systems based on such commercial polymers may have as a drawback their degree of purity, which may affect the separation procedure. However, their lower cost should encourage studies on their use in aqueous two-phase polymer extraction. The influence of temperature, pH, and ionic strength on the partition of several different molecular weight and isoelectric point proteins and whole cells was studied. The results obtained were compared with corresponding dextran-PEG systems, Aquaphase PPT-PEG systems, crude dextran-PEG systems, maltodextrin-PEG systems, and Klucel L-pluronic systems. Protein partition coefficient results exhibited higher values than those in corresponding systems. It is shown that this system, based on a crude hydroxypropyl starch, is highly attractive as an initial purification step.

Thoracoscopic ligation of the thoracic duct.

OBJECTIVE: When nonoperative treatment of chylothorax fails, thoracic duct ligation is usually performed through a thoracotomy. We describe two cases of persistent chylothorax, in a child and an adult, successfully treated with thoracoscopic ligation of the thoracic duct. METHODS: A 4-year-old girl developed a right chylothorax following a Fontan procedure. Aggressive nonoperative management failed to eliminate the persistent chyle loss. A 72-year-old insulin-dependent diabetic man was involved in a motor vehicle accident, in which he sustained multiple fractured ribs, a right hemopneumothorax, a right femoral shaft fracture, and a T-11 thoracic vertebral fracture. Subsequently, he developed a right chylothorax, which did not respond to nonoperative management. Both patients were successfully treated with thoracoscopic ligation of the thoracic duct. RESULTS: The child had significant decrease of chyle drainage following surgery. Increased drainage that appeared after the introduction of full feedings five days postoperatively was controlled with the somatostatin analog octreotide. The chest tube was removed two weeks after surgery. After two years' follow-up, she has had no recurrence of chylothorax. The adult had no chyle drainage following surgery. He was maintained on a medium-chain triglyceride diet postoperatively for two weeks. The chest tube was removed four days after surgery. After six months' follow-up, he has had no recurrence of chylothorax. CONCLUSIONS: Thoracoscopic ligation of the thoracic duct provides a safe and effective treatment of chylothorax and may avoid thoracotomy and its associated morbidity.

Malolactic fermentation of wines with immobilised lactic acid bacteria - influence of concentration, type of support material and storage conditions.

Corn cobs, grape skins and grape stems were evaluated as support materials for immobilization of the lactic acid bacteria Oenococcus oeni. The support materials with immobilized cells were further used in malolactic fermentation (MLF) of white wine. Viability of using the immobilized supports was evaluated in consecutive batch fermentations under different conditions of temperature, ethanol and SO(2). Additionally, the possibility of storage and operational stability of the immobilized supports was also studied. All the three supports presented large potential for immobilization of O. oeni cells. The consecutive batches of MLF were successfully conducted for a total period of around 5 months with the possibility of storage of the biocatalyst for 30 d in wine at 25°C.

Partial characterization of biosurfactant from Lactobacillus pentosus and comparison with sodium dodecyl sulphate for the bioremediation of hydrocarbon contaminated soil.

The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2-CH3 and C-O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg(-1) of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.