Potencial quimiopreventivo de lipídios estruturados obtidos da Tributirina e Tricaprilina na fase de promoção da hepatocarcinogênese experimental / Chemopreventive potential of structured lipids obtained from Tributyrin and Tricaprylin in the promotion phase of experimental hepatocarcinogenesis

A quimioprevenção do câncer refere-se ao uso de compostos naturais ou sintéticos para prevenir o desenvolvimento das neoplasias antes do estabelecimento da malignidade. O ácido butirico (AB) atua como um potente quimiopreventivo na hepatocarcinogênese, reduzindo o número e o tamanho de lesões pré neoplásicas persistentes (pLPN), induzindo a apoptose e modulando mecanismos epigenéticos. Já o ácido caprílico (AC), além da sua atuação como potencializador de absorção, vem sendo investigado na área da prevenção do câncer. Neste cenário, o objetivo do trabalho visa avaliar a atividade quimiopreventiva de lipídios estruturados (EST) obtidos por interesterificação enzimática da tributirina com a tricaprilina, na fase de promoção da hepatocarcinogênese experimental. Após o processo de interesterificação, o produto final apresentou novos triacilgliceróis com composição de duas moléculas de ácido butírico para uma de ácido caprilíco. Ratos machos isogênicos da linhagem Fischer 344 foram submetidos ao modelo do hepatócito resistente, sendo distribuídos em dois grupos e tratados diariamente por via intragástrica com lipídios estruturados (EST) ou com o seu controle isocalórico, a maltodextrina (MD), durante a fase de promoção. Como esperado, não houve diferença estatística (p>0,05) em relação ao peso inicial e final dos animais dos grupos MD e EST, o que indica ausência de toxicidade dos compostos administrados. Na análise macroscópica do fígado, foi observada uma redução de 33,3% no grupo EST em relação ao número médio de nódulos macroscópicos em comparação ao grupo MD, porém essa redução não atingiu diferença estatística (p>0,05). Para a avaliação das lesões pré neoplásicas (LPN) foi utilizada a marcação imunoistoquímica para glutationa-S-transferase (GST-P). O grupo EST apresentou uma redução no número de lesões em remodelação e total GSTP-P+, quando comparado com o grupo MD (p<0,05). Quando avaliada a % de corpúsculos apoptóticos e índice de proliferação celular, não houve diferença estatística entre os grupos (p>0,05). Animais tratados com lipídios estruturados apresentaram maiores (p<0,05) concentrações de AC e AB por grama de tecido hepático em relação ao tratamento com maltodextrina. Em relação aos danos no DNA, o grupo EST resultou em cometas de comprimentos menores (p<0,05), menores níveis de γ-H2AX (p<0,05) e maiores concentrações de p53 nuclear, quando comparados aos animais que receberam maltodextrina, sugerindo uma proteção contra danos no DNA no grupo tratado com EST. Os resultados mostraram que o tratamento com EST resultou em ações efetivas na fase de promoção da hepatocarcinogênese experimental

Cancer chemoprevention refers to the use of natural or synthetic compounds to prevent the development of neoplasms before the establishment of malignancy. Butyric acid (AB) acts as a potent chemopreventive in hepatocarcinogenesis, reducing the number and size of persistent preneoplastic lesions (pLPN), inducing apoptosis and modulating epigenetic mechanisms. Caprylic acid (CA), in addition to its role as an absorption enhancer, has been investigated in the area of cancer prevention. In this scenario, the objective of this work was to evaluate the chemopreventive activity of structured lipids (EST) obtained by enzymatic interesterification of tributyrin with tricaprylin, in the phase of promotion experimental hepatocarcinogenesis. After the interesterification process, the final product presented new triacylglycerols with a composition of two molecules of butyric acid to one of caprylic acid. Isogenic male Fischer 344 rats were submitted to the resistant hepatocyte model, divided into two groups and treated daily intragastrically with structured lipids (EST) or with its isocaloric control, maltodextrin (MD), during the promotion phase. As expected, there was no statistical difference (p>0.05) in relation to the initial and final weight of the animals in the MD and EST groups, which indicates the absence of toxicity of the administered compounds. In the macroscopic analysis of the liver, a reduction of 33.3% was observed in the EST group in relation to the mean number of macroscopic nodules compared to the MD group, but this reduction did not reach a statistical difference (p>0.05). For the evaluation of pre-neoplastic lesions (PNL) immunohistochemical staining for glutathione-Stransferase (GST-P) was used. The EST group showed a reduction in the number of remodeling lesions and total GSTP-P+, when compared to the MD group (p<0.05). Animals treated with structured lipids had higher (p<0.05) concentrations of AC and AB per gram of liver tissue compared to treatment with maltodextrin. Regarding DNA damage, the EST group resulted in comets of shorter lengths (p<0.05), lower levels of γ-H2AX (p<0.05) and high concentration of nuclear p53, when compared to animals that received maltodextrin, suggesting protection against DNA damage in the EST treated group. The results showed that EST treatment resulted in effective actions in the promotion phase of experimental hepatocarcinogenesis

Lipase Production by Aspergillus niger C by Submerged Fermentation

Abstract This study aimed to evaluate the effects of variables on the process of lipases production by Aspergillus niger C by submerged fermentation (SmF). The production assays were performed in shake flasks for 72 hours at 150 rpm and 32°C. First, a fractional factorial design 25-1 (FFD) was carried out to evaluate the effect of the following process variables: sucrose, ammonium sulphate, soybean oil, yeast extract concentration and pH. After the selection of the variables that significantly influenced the lipase production, a central composite rotational design 22 (CCRD) was used, aiming to find the most favorable operational conditions. The selected assay condition (15.0 g.L-1 sucrose, 4.0 g.L-1 ammonium sulphate, 4.0 g.L-1 soybean oil and 1.0 g.L-1 yeast extract at pH 5.0) was the one that presented a lipase activity of 27.46 U.mL-1. It was very close to that best assay (30.76 U.mL-1), but using half of the inducer concentration, consequently reducing process cost. The kinetics of lipase production showed that the highest specific activity was 57.17 U.mg-1. The pH and temperature effects on lipase activity produced in this study was investigated. The optimum activity was found in a more acidic pH (5.0-6.0) and 55°C.

Acute pancreatitis associated with pegylated interferon-alpha-2a therapy in chronic hepatitis C

Chronic hepatitis C virus (HCV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma. Combination therapy of pegylated interferon-alpha (PEG-IFN-α) and ribavirin (RBV) is a current standard treatment for chronic HCV infection in Korea, which has considerable adverse effects. Acute pancreatitis is a rare complication of PEG-IFN-α administration. We report a case of a 62-year-old female who experienced acute pancreatitis after 4 weeks of PEG-IFN-α-2a and RBV combination therapy for chronic HCV infection. The main cause of the acute pancreatitis in this case was probably PEG-IFN-α rather than RBV for several reasons. A few cases have been reported in which acute pancreatitis occurred during treatment with PEG-IFN-α-2b. This is the first report of acute pancreatitis associated with PEG-IFN-α-2a in Korea.

Influence of carvacrol and thymol on the physiological attributes, enterotoxin production and surface characteristics of Staphylococcus aureus strains isolated from foods

This study evaluated the influence of the phenolic compounds carvacrol (CAR) and thymol (THY) on some physiological characteristics and on the modulation of the secretion of some staphylococcal virulence factors, that is, coagulase and enterotoxin. This study also investigated possible mechanisms for the establishment of the anti-staphylococcal activity of these compounds. Sublethal concentrations (0.3 and 0.15 µL/mL) of CAR and THY inhibited the activity of the enzymes coagulase and lipase and led to a decrease in salt tolerance. At the tested sublethal concentrations, both CAR and THY led to a total suppression of enterotoxin production. The loss of a 260-nm-absorbing material and an efflux of potassium ions occurred immediately after the addition of CAR and THY at 0.6 and 1.2 µL/mL and increased up to 120 min of exposure. Electron microscopy of cells exposed to CAR and THY (0.6 µL/mL) revealed that individual cells appeared to be deformed, with projections of cellular material. The observations of leakage of cellular material and an altered cell surface suggest that gross damage to a cell's cytoplasmic membrane, which results in a disruption in protein secretion, could be responsible for the anti-staphylococcal properties of CAR and THY.

Computation of interactive effects and optimization of process parameters for alkaline lipase production by mutant strain of Pseudomonas aeruginosa using response surface methodology

Alkaline lipase production by mutant strain of Pseudomonas aeruginosa MTCC 10,055 was optimized in shake flask batch fermentation using response surface methodology. An empirical model was developed through Box-Behnken experimental design to describe the relationship among tested variables (pH, temperature, castor oil, starch and triton-X-100). The second-order quadratic model determined the optimum conditions as castor oil, 1.77 mL.L-1; starch, 15.0 g.L-1; triton-X-100, 0.93 mL.L-1; incubation temperature, 34.12 ºC and pH 8.1 resulting into maximum alkaline lipase production (3142.57 U.mL-1). The quadratic model was in satisfactory adjustment with the experimental data as evidenced by a high coefficient of determination (R²) value (0.9987). The RSM facilitated the analysis and interpretation of experimental data to ascertain the optimum conditions of the variables for the process and recognized the contribution of individual variables to assess the response under optimal conditions. Hence Box-Behnken approach could fruitfully be applied for process optimization.

'Synthetic lipase' production from a newly isolated Sporidiobolus pararoseus strain by submerged fermentation

The lipase produced by a newly isolate Sporidiobolus pararoseus strain has potential catalysis ability for esterification reactions. In order to improve its synthetic activity, this work aimed at optimizing 'synthetic lipase' production by submerged fermentation of a conventional media based on peptone, yeast extract, NaCl and olive oil using experimental design technique. According to the results obtained in the first experimental design (2(4-1)), yeast extract and NaCl concentrations were tested to further optimization by response surface methodology. The maximum 'synthetic lipase' activity obtained was 26.9 U/mL in the optimized media (5.0, 6.8, 7.0 and 1.0% (wt/v) of peptone, yeast extract, NaCl and olive oil, respectively), representing a 6.36-fold increase compared to the initial medium. The time course of 'synthetic lipase' production in the optimized condition was evaluated in terms of synthetic activity, protease activity, biomass and total carbon and the maximum synthetic activity was observed during the stationary phase of growth.

Razão triglicerídeo/HDL-C como indicador de risco cardiovascular em alcoolistas crônicos / Triglyceride/HDL-C ratio as a cardiovascular risk indicator in chronic alcoholic patients

Fundamentos: O consumo de grande quantidade de bebidas alcoólicas associa-se a alterações no sistemacardiovascular. A utilização da razão triglicerídeo/HDL-C (TG/HDL-C) apresenta-se como forte marcadoraterogênico. Objetivos: Estabelecer o perfil lipídico e razão TG/HDL-C de alcoolistas crônicos e comparar comindivíduos não alcoolistas. Métodos: Estudo de caso-controle compreendendo 50 indivíduos alcoolistas crônicos e 50 indivíduos não alcoolistas do mesmo sexo correspondente e idadessemelhantes. Foram analisadas variáveis referentes às condições socioeconômicas e de estilo de vida,antropometria e perfil lipídico de ambos os grupos, além da pressão arterial do grupo de alcoolistas. Com os resultados de triglicerídeo e HDL-C foi possível o cálculo da razão TG/HDL-C. Resultados: Com relação aos dados socioeconômicos e de estilo de vida não houve diferenças em relação à prática de atividade física e comorbidades. Quanto àantropometria, o grupo alcoolista apresentou valores menores de IMC, circunferência da cintura e razãocintura/estatura. Sobre o perfil lipídico e razão TG/HDL-C não houve diferença entre os grupos, apenas em relação ao HDL-C. A razão TG/HDL-C apresentouassociação com o IMC e razão cintura/estatura no grupo dos alcoolistas crônicos e com o IMC, circunferência da cintura, razão cintura/estatura e índice de conicidade no grupo dos não alcoolistas.Conclusão: O grupo de alcoolistas crônicos estudado apresentou melhor perfil bioquímico e razão TG/HDL-Cem comparação ao grupo de não alcoolistas.

Optimization of extracellular thermophilic highly alkaline lipase from thermophilic Bacillus sp isolated from Hotspring of Arunachal Pradesh, India

Studies on lipase production were carried out with a bacterial strain (Bacillus sp LBN 2) isolated from soil sample of hotspring of Arunachal Pradesh, India. The cells were cultivated in a mineral medium with maximum production at 1% groundnut oil. The optimum temperature and initial medium pH for lipase production by the organism were 50ºC and 9.0 respectively. The molecular mass was found to be 33KDa by SDS PAGE. The optimal pH and temperature for activity were 10 and 60ºC respectively. The enzyme was found to be stable in the pH range of 8-11 with 90% retention of activity at pH 11. The enzyme retained 90% activity at 60ºC and 70% of activity at 70ºC for 1h. The lipase was found to be stable in acetone followed by ethanol. The present findings suggested the enzyme to be thermophilic alkaline lipase.

Screening and characterization of a novel alkaline lipase from Acinetobacter calcoaceticus 1-7 isolated from Bohai Bay in China for detergent formulation

A novel alkaline lipase-producing strain 1-7 identified as Acinetobacter calcoaceticus was isolated from soil samples collected from Bohai Bay, China, using an olive oil alkaline plate, which contained olive oil as the sole carbon source. The lipase from strain 1-7 showed the maximum activity at pH 9.0 under 40ºC. One interesting feature of this enzyme is that it exhibits lipase activity over a broad range of temperatures and good stability. It is also stable at a broad range of pHs from 4.0 to 10.0 for 24 h. Its catalytic activity was highly enhanced in the presence of Ca2+, Mg2+ and K+, but partially inhibited by Cu2+, Al3+, Fe3+ , Ba2+and Zn2+. The fact that it displays marked stability and activity in the presence of TritonX-100, Tween-20, Tween-80, SDS, Hydrogen peroxide, Sodium perborate, Sodium hypochlorite, Sodium citrate, Sodium taurocholate, Glycerine and NaCl suggests that this lipase is suitable as an additive in detergent formulations.

Hydrolytic potential of a psychrotrophic Pseudomonas isolated from refrigerated raw milk

The production of extracellular hydrolases by a psychrotrophic bacterium isolated from refrigerated raw milk, and identified as a Pseudomonas sp. belonging to the Pseudomonas jenssenii group, was studied. This bacterium produced proteolytic and lipolytic enzymes in all media investigated (skim milk, cheese whey, casein broth, and tryptone soy broth). High levels of á-glucosidase were produced in skim milk broth. Hydrolytic enzymes detected in skim milk broth are of particular concern, indicating that these enzymes could be produced by Pseudomonas sp. during the cold storage of raw milk, contributing to the spoilage problem in milk and dairy products.

Biological activities of a mixture of biosurfactant from Bacillus subtilis and alkaline lipase from Fusarium oxysporum

In this study, we investigate the antimicrobial effects of a mixture of a biosurfactant from Bacillus subtilis and an alkaline lipase from Fusarium oxysporum (AL/BS mix) on several types of microorganisms, as well as their abilities to remove Listeria innocua ATCC 33093 biofilm from stainless steel coupons. The AL/BS mix had a surface tension of around 30 mN.m-1, indicating that the presence of alkaline lipase did not interfere in the surface activity properties of the tensoactive component. The antimicrobial activity of the AL/BS mix was determined by minimum inhibitory concentration (MIC) micro-assays. Among all the tested organisms, the presence of the mixture only affected the growth of B. subtilis CCT 2576, B. cereus ATCC 10876 and L. innocua. The most sensitive microorganism was B. cereus (MIC 0.013 mg.mL-1). In addition, the effect of the sanitizer against L. innocua attached to stainless steel coupons was determined by plate count after vortexing. The results showed that the presence of the AL/BS mix improved the removal of adhered cells relative to treatment done without the sanitizer, reducing the count of viable cells by 1.72 log CFU.cm-2. However, there was no significant difference between the sanitizers tested and an SDS detergent standard (p<0.05).

Reflujo pancreáticobiliar en pacientes con colelitiasis y sin colelitiasis: estudio comparativo / Pancreaticobiliary reflux in patients with cholelithiasis and without cholelithiasis: a comparative study

Background. Pancreaticobiliary reflux is a pathologic phenomenon occurring in patients with gallstones. However, the occurrence of pancreaticobiliary reflux has not been studied in patients without gallstones. The objective of this study was to measure the bile levels of amylase and lipase in patients without gallstones submitted to cholecystectomy as part of another surgical procedure, and to compare these values with patients submitted to cholecystectomy for gallstone disease. Patients and Methods. A prospective observational comparative study was designed. A sample of 136 consecutive patients was included. Amylase and lipase levels were measured in bile. Normal serum amylase levels at our institution are 28-100 U/L and for lipase are 13-60 U/L. There are no established normal levels for pancreatic enzymes in bile. However, we considered elevated the bile amylase and lipase levels whenever they were higher than normal plasma levels. Results. One-hundred three patients (76 percent) had gallstones and 33 (24 percent) liad healthy gallbladders without gallstones. According to normal plasma levels for amylase and lipase, these enzymes in bile were elevated in 83.5 percent patients with gallstones, compared to elevated levels of amylase in 6 percent patients and lipase in 3 percent patients without gallstones. Conclusions. Pancreaticobiliary reflux is a common phenomenon in patients with gallstones and occurs sporadically in patients without gallstones.

Introducción. El reflujo pancreáticobiliar es un fenómeno patológico que ocurre en pacientes con colelitiasis. La ocurrencia de este fenómeno no ha sido estudiada en pacientes sin colelitiasis. El presente estudio tiene por objetivo medir los niveles de amilasa y lipasa en la bilis de pacientes sin colelitiasis, colecistectomizados como parte de otro procedimiento quirúrgico y comparar estos valores con pacientes colecistectomizados por colelitiasis. Pacientes y Métodos. Se diseñó un estudio observacional y comparativo. Una muestra de 136 pacientes consecutivos fue incluida. Se midieron los niveles de amilasa y lipasa en la bilis. En nuestra institución los valores normales para amilasa son 28-100 U/L y para lipasa 13-60 U/L. No se han establecido valores normales de enzimas pancreáticas en la bilis. Para efectos del presente estudio, se consideró como elevados los niveles biliares de amilasa y lipasa cuando fueron mayores a los valores plasmáticos normales. Resultados. 103 pacientes (76 por ciento) tenían colelitiasis y 33 (24 por ciento) tenían vesículas normales sin cálculos. De acuerdo a los valores plasmáticos normales de amilasa y lipasa, estas enzimas se encontraron elevadas en 83,5 por ciento de los pacientes con colelitiasis comparados con valores elevados de amilasa en 6 por ciento en pacientes sin colelitiasis y de lipasa en 3 por ciento de estos pacientes. Conclusiones. El reflujo pancreaticobiliar es un fenómeno común en pacientes con colelitiasis y ocurre esporádicamente en pacientes sin colelitiasis.

Concomitant production of protease and lipase by Bacillus licheniformis VSG1: production, purification and characterization

This study was aimed at producing protease and lipase simultaneously on a common medium by Bacillus licheniformis VSG1, which was isolated from a tannery effluent. The effect of media composition with respect to protein source, lipid source and emulsifier on the production of protease and lipase was analysed. Both those enzymes were produced under optimized conditions like pH, temperature and incubation time. The enzyme mixture comprising of both protease and lipase was purified by ammonium sulphate precipitation, dialysis and gel filtration chromatography to obtain 20-fold pure enzymes. The purified enzyme mixture was characterized to determine the optimum pH and temperature of protease and lipase, the response of the enzymes to inhibitors, additives and solvents. The molecular weight of both the enzymes was determined as 40 kDa on SDS-PAGE. The concomitant production of protease and lipase and the purification of both the enzymes in a single mixture have industrial significance, as many industrial processes use both protease and lipase together.

Screening of microbial lipases and evalutaion of their potential to produce glycerides with high gamma linolenic acid concentration

Gamma-linolenic acid (GLA, 18:3, cis- 6,9,12-octadecatrienoic acid), an important compound in n-6 eicosanoid family biosynthesis, occurs in the lipids of a few plant and microbial sources. This study focused on the screening of microbial strains with suitable lipase activity for enrichment of GLA by selective hydrolysis of the borage oil (21.6 percent of GLA/total fatty acids). Firstly, 352 microrganisms were tested for their lipolytic capacity using screening techniques on agar plates containing borage oil, strains were then selected and screened for their activity (U/mg) using both submerged fermentation (SmF) and solid state fermentation (SSF). The rate of hydrolysis and the selective preference of these hydrolytic enzymes towards fatty acids, with a special focus on enrichment of GLA were studied and compared with those obtained by two commercially-available lipases. Only one of the lipases tested during this study displayed selectivity, discriminating the GLA during the hydrolysis reaction. Using the enzymatic extract from Geotrichum candidum as a biocatalyst of the reaction, it was possible to obtain a percentage of 41.7 percent of GLA in acylglycerols fraction when the borage oil was treated in a fixed-bed reactor for 24 hours at 30ºC.

Purification and characterization of extracellular lipase from a new strain: Pseudomonas aeruginosa SRT 9 / Purificação e caracterização de uma lipase extracelular produzida por uma nova cepa: Pseudomonas aeruginosa SRT9

An extra cellular lipase was isolated and purified from the culture broth of Pseudomonas aeruginosa SRT 9 to apparent homogeneity using ammonium sulfate precipitation followed by chromatographic techniques on phenyl Sepharose CL- 4B and Mono Q HR 5/5 column, resulting in a purification factor of 98 fold with specific activity of 12307.8 U/mg. The molecular weight of the purified lipase was estimated by SDS-PAGE to be 29 kDa with isoelectric point of 4.5. Maximum lipase activity was observed in a wide range of temperature and pH values with optimum temperature of 55ºC and pH 6.9. The lipase preferably acted on triacylglycerols of long chain (C14-C16) fatty acids. The lipase was inhibited strongly by EDTA suggesting the enzyme might be metalloprotein. SDS and metal ions such as Hg2+, Zn2+, Cu2+, Ag2+ and Fe2+ decreased the lipase activity remarkedly. Its marked stability and activity in organic solvents suggest that this lipase is highly suitable as a biotechnological tool with a variety of applications including organo synthetic reactions and preparation of enantiomerically pure pharmaceuticals. The Km and Vmax value of the purified enzyme for triolein hydrolysis were calculated to be 1.11 mmol/L and 0.05 mmol/L/minrespectively.

Uma lipase extracelular foi isolada e purificada a partir de um caldo de cultura de Pseudomonas aeruginosa SRT9 até homogeneidade visível empregando-se precipitação com sulfato de amônia, seguida de técnicas cromatográficas em colunas de fenil sefarose CL-4B e Mono Q HR 5/5, obtendo-se um fator de purificação de 98 vezes, e atividade especifica de 12307,8 U/mg. Por SDS_PAGE, estimou-se que o peso molecular da lipase purificada é 29kDa, com um ponto isoelétrico de 4,5. A lipase apresentou atividade máxima em uma ampla faixa de temperatura e pH, com ótimos a 55ºC e pH 6,9. A lípase foi mais ativa sobre triacilglicerois de cadeia longa (C14-C16). A lipase foi fortemente inibida por EDTA, o que sugere que a enzima pode ser uma metaloproteína. SDS e íons metálicos, como Hg2+, Zn2+,Cu2+, Ag2+ e Fe2+, diminuíram marcadamente a atividade da lipase. Sua grande estabilidade e atividade em solventes organicos sugerem que esta lípase pode ser uma excelente ferramenta tecnológica com várias aplicações como reações organosintéticas e preparação de produtos farmacêuticos enantiomericamente puros. Os valores de Km e Vmax para a enzima purificada na hidrólise de trioleina foram 1,11 mmol/L e 0,05 mmol/L/min, respectivamente.

Novel agents for enzymatic and fungal hydrolysis of stevioside / Novos agentes para a hidrólise enzimática e fúngica do esteviosídeo

A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae) and enzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger atpH 7 (20.8% yield).

Um estudo comparativo do potencial de alguns agentes biológicos capazes de hidrolisar o esteviosídeo foi realizado,objetivando-se estabelecer uma metodologia alternativa para a obtenção da aglicona esteviol ou seu produto de rearranjo, isoesteviol, em rendimentos elevados que permitam o uso destas agliconas para o preparo de novos compostos bioativos. As reações de hidrólise foram realizadas usando fungosfilamentosos (Aspergillus niger, Rhizopus stolonifer e Rhizopus arrhizus), uma levedura (Saccharomyces cerevisiae) e enzimas(pancreatina, lipase PL250 e lipase VFL 8000). A pancreatina mostrou a melhor atividade hidrolítica dentre os sistemastestados, fornecendo isoesteviol com rendimento de 93,9% em pH 4,0, usando tolueno como co-solvente. Esteviol foi produzido tanto usando pancreatina em pH 7,0 (20,2% derendimento) quanto usando A. niger em pH 7,0 (20,8% de rendimento).

Severe Acute Liver and Pancreas Damage in Anorexia Nervosa / 대한소화기학회지

Anorexia nervosa, a syndrome most commonly affecting young women, is characterized by weight less than 85% of weight that is considered normal for that person's age and height, distorted body image, and fear of becoming obese, and its mortality is up to 9%. We present a case of a 33-year-old woman with a 9-year history of anorexia nervosa. She admitted to our institution with decreased mentality, and her body mass index was 11.5 kg/m2 of the time admission. Initial aminotransferase level was severely elevated, but it was normalized solely with improved nutrition and weight gain. Five and sixteen days after the admission urinary tract infection and elevation of pancreatic enzymes occurred. They were successfully treated with antibiotics and nutritional support. Fifty seven days after the admission, she discharged. We report a case of acute hepatitis and pancreatitis treated with nutritional rehabilitation in a patient with severe anorexia nervosa for the first time in Korea.

Utilization of agroindustrial residues for lipase production by solid-state fermentation / Utilização de resíduos agroindustriais para produção de lipase por fermentação em estado sólido

The aim of this work was to produce lipases by solid-state fermentation (SSF) using, as substrate, agroindustrial residue supplemented with by-products from corn oil refining process or olive oil. For a group of ten fungi strains selected in the first steps, the lipase activity obtained by SSF varied from 7.7 to 58.6 U/g of dry substrate (gds). Among the evaluated strains, the Aspergillus niger mutant 11T53A14 was selected by presenting the best enzymatic production. For the fermentation tests, two substrates were also investigated: wheat bran and corn cob, both supplemented with olive oil. The best results were obtained with wheat bran. Additionally, three industrial by-products from corn oil refining (soapstock, stearin and fatty acids) were evaluated as substitutes to the olive oil in the function of lipases production inducer. Among them, soapstock and stearin were the best inducers, whereas fatty acids presented an inhibitor effect. The highest lipase activities using soapstock, stearin and fatty acids were 62.7 U/gds, 37.7 U/gds and 4.1 U/gds, respectively.

O objetivo deste trabalho foi produzir lipases por fermentação em estado sólido (FES) utilizando, como substrato, resíduo agroindustrial enriquecido com subprodutos do processo de refino do óleo de milho ou óleo de oliva. Para um conjunto de dez linhagens de fungos selecionadas nas primeiras etapas, a atividade lipásica obtida por FES variou de 7,7 a 58,6 U/g de substrato seco (gss). Dentre as linhagens avaliadas, o mutante Aspergillusniger 11T53A14 foi selecionado por apresentar a melhor produção enzimática.Para os testes de fermentação, dois substratos foram investigados: farelo de trigo e sabugo de milho, ambos enriquecidos com óleo de oliva. Nestes testes, os melhores resultados foram obtidos com farelo de trigo. Adicionalmente, três subprodutos industriais do refino do óleo de milho (borra, estearina e ácidos graxos) foram avaliados como substitutos do óleo de oliva na função de indutor para a produção de lipases. Dentre eles, borra e estearina demonstraram ser melhores indutores, enquanto ácidos graxos apresentaram um efeito inibidor. As mais altas atividades lipásicas utilizando borra, estearina e ácidos graxos foram 62,7 U/gss, 37,7 U/gss e 4,1 U/gss, respectivamente.

Biofilm formation by Stenotrophomonas maltophilia isolates from device-associated nosocomial infections / Formación de biopelículas por aislamientos de Stenotrophomonas maltophilia recuperados de infecciones nosocomiales asociadas al uso de dispositivos médicos

Medical devices are often colonized by bacteria which may cause severe infections. The aim of this work was to evaluate biofilm formation by S. maltophilia isolates from device-associated nosocomial infections. The 13 local isolates exhibited different capacities of biofilm formation on hydrophilic and hydrophobic surfaces. All isolates formed strong biofilms in polystyrene microplates, while strong, moderate or weak biofilms were detected in borosilicate (BS) or polypropylene (PP) tubes. The proficiency of biofilm formation was better evaluated by the level of crystal violet staining expressed relative to the final culture density. The microscopic analysis of biofilms formed on glass coverslips revealed the presence of a matrix of exopolysaccharides and microcolonies typical of biofilm architecture. Isolates with increased adhesion to BS showed larger microcolonies. According to our results, twitching correlated well with attachment to the three abiotic surfaces tested, while swimming only showed a slight correlation with biofilm formation on PP. Poor correlation was observed between cell surface hydrophobicity and biofilm formation. One of the highest biofilm-producing isolates adhered to urethral catheters of different materials, and exhibited an increased resistance to oxidative stress, one of the common stresses encountered by bacteria during the infection process due to the immune response.

El objetivo de este trabajo fue evaluar la formación de biopelículas por parte de aislamientos de Stenotrophomonas maltophilia. Los 13 aislamientos locales evaluados mostraron diferente capacidad de formar biopelículas en superficies hidrofílicas e hidrofóbicas. Todos ellos formaron biopelículas fuertes en microplacas de poliestireno (PS), mientras que se observaron biopelículas fuertes, moderadas o débiles en tubos de borosilicato (BS) o polipropileno (PP). La medida del cristal violeta unido a la biopelícula expresada en función de la densidad final de los cultivos permitió una mejor evaluación de la eficiencia de formación de biopelículas. El análisis microscópico de biopelículas formadas sobre cubreobjetos mostró la presencia de una matriz de exopolisacáridos y microcolonias típicas de la arquitectura de las biopelículas. Los aislamientos con mayor adhesión a BS mostraron microcolonias de mayor tamaño. La motilidad asociada a superficies ( twitching) presentó buena correlación con la adhesión a BS, PP y PS, mientras que la motilidad asociada a flagelos solo correlacionó ligeramente con la adhesión a PP. La correlación entre la hidrofobicidad de la superficie bacteriana y la formación de biopelículas fue escasa. Uno de los aislamientos productores de biopelículas fuertes evidenció capacidad de adhesión a catéteres uretrales de diferentes materiales y mayor resistencia al estrés oxidativo.

Hipertrigliceridemia: implicações clínicas e terapêuticas / Hypertriglyceridaemia: clinical and therapeutical implications

A hipertrigliceridemia tem sido associada a risco de doença arterial coronária, mas sua associação não é tão forte como a da lipoproteina de baixa densidade (LDL), e a relação dos triglicérides com a aterosclerose tem sido fonte de certa confução para os clínicos. Tal confusão decorre em parte dos dados pouco expressivos obtidos dos estudos epidemiológicos, quando são extrapolados para o cenário clínico. Níveis elevados de triglicérides(menos 180mg/dl) associados a níveis baixos de colesterol de lipoproteína de alta densidade (HDL-colesterol)(maior 40mg/dl) são preditores de risco coronário elevado, principalemente se a relação colesterol total/HDL-colesterol for superior a 5. Os fibratos contribuem para importante redução dos níveis de triglicérides, atuando discretamente sobre os níveia de LDL-colesterol, tendo papel destacado no aumento dos níveis de HDL-colesterol. Segundo os resultados de alguns estudos, existem evidências da importância da redução dos níveis séricos das concentrações da lipoproteína de muito baixa densidade (VLDL), como demonstrado no estudo angiográfico BECAIT, em que os níveis de LDL-colesterol não foram afetados e os benefícios clínicos e angiográficos parecem estar relacionados à redução dos níveis de triglicérides(VLDL) e de fibrinogênio, com elevação dos níveis de HDL-colesterol.