Volatiles from Subtropical Convolvulaceae That Interfere with Bacterial Cell-to-Cell Communication as Potential Antipathogenic Drugs

Increasing chronic bacterial infections create an urgent need for new antimicrobial agents or strategies for their control. Targetingvirulence is one of the alternative approaches to find new medicines to treat persistent infections due to bacteria with biofilmphenotypewhich are more resistant to antibiotics than their planktonic counterparts having an extreme capacity for evading the host defences. A bioguided study of sixteen extracts from flowers and leaves of four subtropical Convolvulaceae species provided evidence of the occurrence of antipathogenic natural products active against Gram positive and negative bacteria.Particularly, volatile metabolites from Merremia dissecta creeper, a food and medicinal plant, were able to interfere with the Pseudomonas aeruginosa quorum sensing system by a strong decrease of N-acyl homoserine lactone (AHL) biosynthesis (63?75%), which attenuated the virulence factor expression like biofilm (55%) and elastase activity (up to 27%), key factors thatenable the colonization and dissemination of the infection in the host. Control of the P. aeruginosa biofilm and the QS process by phytochemicals, such as (+) spathulenol, isolated from a bioactive extract of M. dissecta leaves would be a good strategy for the development of new and effective antipathogenic drugs.Fil: Luciardi, María Constanza. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Pérez Hernández, María Victoria. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Muruaga, Nora. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Arena, Mario Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Cartagena, Elena. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentin

Nutraceutical Properties and Toxicity Studies of Flour Obtained from Capsicum pubescens Fruits and Its Comparison with “Locoto” Commercial Powder

The aim of this research was to evaluate the phytochemical profiles of flour from red, yellow and green fruits of Capsicum pubescens (commun name: locoto) and compare with “locoto” commercial powder (Lcp). Soluble protein (SP), total sugar (TS), free phenolic compounds (FPC), ascorbic acid (AA), total monomeric anthocyanin (TMA), condensed and hydrolizable tannin (CT, HT) and carotenoids (C) were determined by spectrophotometric methods. Multielemental composition by ICP-MS was also done. The flour showed low amounts of calories and high potassium and low sodium levels. Flour from “locoto” fruits contained mainly carotenoids (0.82 to 20 g Eβ-C/100g DW), polyphenolic compounds (681 - 822 mg GAE/100g DW) and ascorbic acid (100 - 199 mg AA/100g DW). The polyphenolic profile of Lcp was similar to flour obtained in our laboratory but the level of carotenoid was lower than that of flour. The fiber content of flour was around 3% in all cases. All preparations obtained from flour and Lcp showed antioxidant activity with SC50 values between 1.4 and 3 μg GAE/mL. Inhibitory capacity on Lipo-oxygenase enzyme was also demonstrated. Non mutagenic effect was detected. The “locoto” flour showed nutraceutical characteristics that are demanded by functional food and could be used as a dietary supplement.Fil: Rivas, Marisa Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Vignale, Nilda Dora. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ordóñez, Roxana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Zampini, Iris Catiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Alberto, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Sayago, Jorge Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Structural factors of annonaceous acetogenins and their semisynthetic analogues related with the toxicity on Spodoptera frugiperda

Toxic and nutritional effects of annonaceous acetogenins and their semisynthetic analogues on Spodoptera frugiperda were evaluated. Structural modification of the natural ACG, blocking the OH flanking THF with MOM, allowed us to suggest the mode of action of ACG in the membrane. Our study emphasizes the role of the flanking OH and acetyl groups of THF with the membrane hydrophilic polar head groups. They are essential structural factors in the ACG that facilitate the intermolecular interaction that dehydrates the membrane and makes it potentially toxic against Spodoptera frugiperda.Fil: Di Toto Blessing, Lilian Edith. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Budeguer, Florencia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Ramos, Juan. Universidad de la República. Facultad de Química. Departamento de Química Orgánica; UruguayFil: Bardon, Alicia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Díaz, Sonia Beatriz. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Brovetto, Margarita. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Seoane, Gustavo. Universidad de la República. Facultad de Química. Departamento de Química Orgánica; UruguayFil: Neske, Adriana. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; Argentin

Inhibition of an extracellular polygalacturonase from Geotrichum candidum by a proteinaceous inhibitor isolated from lemon fruits

An extracellular polygalacturonase [EC 3.2.1.15], named PG-543, was purified from the culture of Geotrichum candidum IEV 543, a phytopathogenic fungi isolated from infected lemon. The molecular mass of the enzyme was estimated to be 26 kDa by SDS-PAGE. The pH optimum determined was 5.5; the enzyme showed high stability in the pH range between 4.0 and 6.0. The temperature optimum was 37 ºC. Furthermore, a proteinaceous inhibitor of the polygalacturonase (PG) named PGIP was isolated from lemon albedo. This protein was able to maintain the inhibitory activity in a wide range of pH and temperature. The maximal interaction between PG-PGIP was reached after 20 min of contact. PGIP did not show toxic effect on Artemia salina in the concentration range that was active on PG enzyme. Also, the proteinaceous inhibitor did not show mutagenic nor phytotoxic effects.Our results suggest that, the PGIP isolated from lemon could be used as a natural product to decrease the propagation of pathogenic fungi responsible for postharvest diseases in citrus by the inhibition of hydrolytic enzymes secreted by pathogens.Fil: Rodriguez, Ivana Fabiola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Torres, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Sayago, Jorge Esteban. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Zampini, Iris Catiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Ordóñez, Roxana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentin

Theoretical and experimental study of a new thiosulfonate derivative: Methyl trifluoromethanethiosulfonate, CF3SO2SCH3. Conformational transferability in CX3SO2S-R compounds

Methyl trifluoromethanethiosulfonate, CF3SO2SCH3, was synthesized and characterized by 13C NMR, 19F NMR, and vibrational spectroscopy. This structural study was supported by MP2 and DFT (B3LYP and MPW1PW91) calculations, which revealed a strong dependence of the theoretical structure on the polarization of the basis set. Theoretical data indicate that only one conformer, gauche, is predicted by rotating around the S–S bond. This conformational preference was studied using the total energy scheme and natural bond orbital partition scheme. These results evidence that electron delocalization and especially LP S → σ∗ C(1)-S interactions play an interesting role in the reactivity-structure connection of oxoesters and thioesters. Gas and liquid infrared and liquid Raman spectra were recorded and assigned. The experimental vibrational data along with theoretical force constants (B3LYP) were used to define a scaled quantum mechanical force field, which enabled the reproduction of the measured frequencies with a final root-mean-square deviation of 8.06 cm−1.Fil: Galván, Jorge Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Contreras Aguilar, Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; ArgentinaFil: Defonsi Lestard, Maria Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Tuttolomondo, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Ulic, Sonia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Ben Altabef, Aída. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Antimicrobial activity of nine extracts of sechium edule (Jacq) swartz

The antimicrobial properties of Sechium edule (Jacq) Swartz alcoholic extracts obtained according to the Farmacopea Argentina (6th edn) were tested against bacteria of clinical relevance as nosocomial pathogens. To evaluate antibacterial activity, the disc diffusion assay was carried out with several gram-positive bacteria (Enterococcus faecalis, Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus pyogenes, Streptococcus agalactiae, Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212). This assay was suitable for the screening of a large number of extracts at one time. All ethanolic extracts showed activity against gram-positive bacteria. Minimal inhibitory concentration (MIC) values were determined with a microdilution assay. The highest activity was obtained with the 80% aqueous-ethanolic leaf extract (MIC values of 4.16/8.32 mg/ml against staphylococci and enterococci) and with the 96% ethanolic seed extract (MIC values of 8.32/16.64 mg/ml and /8.32 mg/ml against staphylococci and enterococci, respectively). The results indicate that both fluid extract and tincture have very good antimicrobial efficacy against all strains of multiresistant staphylococci and enterococci. In this study the minimal bactericidal concentration (MBC) values were identical to the MIC values or twofold higher than the corresponding MIC. This may indicate a bactericidal effect. Stored extracts have similar anti-staphylococcal and anti-enterococcal activity to recently obtained extracts. The results obtained might be considered sufficient to warrant further studies aimed at isolation and identification of the active principle.Fil: Ordoñez, Alicia Lucia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Gómez, José D.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Cudmani, Norma Mercedes. Gobierno de la Provincia de Tucumán. Ministerio de Salud. Sistema Provincial de Salud. Hospital de Clínicas "Dr. Nicolás Avellaneda"; Argentina. Gobierno de la Provincia de Tucumán. Ministerio de Salud. Departamento Bioquímico; ArgentinaFil: Vattuone, Marta Amelia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Isla, Maria Ines. Universidad Nacional de Tucumán. Instituto de Bioprospección y Fisiología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Bioprospección y Fisiología Vegetal; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales; Argentin

Prosopis alba seed flour improves vascular function in a rabbit model of high fat diet-induced metabolic syndrome

Aims: Prosopis alba flour is a natural source of nutrient and phytochemicals with potential effects on cardiovascular risk factors. The aim of this work was to examine the effects of dietary supplementation with Prosopis alba seed flour (Pr-Feed) on a high fat diet (FD)-induced rabbit model of metabolic syndrome. Main methods: Rabbits were separated in four groups: fed regular diet (CD); CD supplemented with Pr-Feed; fed on 18 % FD; FD supplemented with Pr-Feed. All diets were administrated for 6 weeks. After the feeding period body weights, mean blood pressure, heart rate and visceral abdominal fat (VAF) were determined; glucose tolerance test (GTT) was performed; total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, triglycerides (TG), fasting glucose (FG), aspartate amino transferase, alanine amino transferase, bilirubin and creatinine were measured in serum. Abdominal aorta was excised and vascular function was assessed by acetylcholine relaxation and contractile response to KCl, norepinephrine and angiotensin II. Key findings: Phytochemical analyses showed that the main compounds of Pr-Feed were apigenin C-glycosides. FD increased VAF, FG, TG, reduced HDL-cholesterol and induced abnormal GTT. Pr-Feed addition to FD did not modify these alterations. Aortic rings from rabbits fed on FD exhibited an impaired relaxation-response to acetylcholine and increased agonist vasoconstrictor responses. Pr Feed-supplemented FD improved the response to acetylcholine, and prevented the increase of the contractile response to KCl, norepinephrine and angiotensin II. Significance: Results suggest that dietary supplementation with Pr-Feed, rich in apigenin C-glycosides, has vascular protector properties and could be used to prevent vascular alterations characterizing the metabolic syndrome.Fil: Cattaneo, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Roco, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Alarcón, Gabriela del Jesús. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Jerez, Susana Josefina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Erythrocyte Catalase Activity in More Frequent Microcytic Hypochromic Anemia: Beta-Thalassemia Trait and Iron Deficiency Anemia

Most common microcytic hypochromic anemias are iron deficiency anemia (IDA) and β-thalassemia trait (BTT), in which oxidative stress (OxS) has an essential role. Catalase causes detoxification of H2O2 in cells, and it is an indispensable antioxidant enzyme. The study was designed to measure erythrocyte catalase activity (ECAT) in patients with IDA (10) or BTT (21), to relate it with thalassemia mutation type (β0 or β+) and to compare it with normal subjects (67). Ninety-eight individuals were analyzed since September 2013 to June 2014 in Tucumán, Argentina. Total blood count, hemoglobin electrophoresis at alkaline pH, HbA2, catalase, and iron status were performed. β-thalassemic mutations were determined by real-time PCR. Normal range for ECAT was 70,0-130,0 MU/L. ECAT was increased in 14% (3/21) of BTT subjects and decreased in 40% (4/10) of those with IDA. No significant difference (p=0,245) was shown between normal and BTT groups, while between IDA and normal groups the difference was proved to be significant (p=0,000). In β0 and β+ groups, no significant difference (p=0,359) was observed. An altered ECAT was detected in IDA and BTT. These results will help to clarify how the catalase activity works in these anemia types.Fil: Lazarte, Sandra Stella. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; ArgentinaFil: Monaco, Maria Eugenia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Biología; ArgentinaFil: Jimenez, Cecilia Laura. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; ArgentinaFil: Ledesma, Miryam Emilse. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; ArgentinaFil: Teran, Magdalena María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; ArgentinaFil: Isse, Blanca Alicia de Los Angeles G.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Aplicada; Argentin

Parasitological Survey of Schoolchildren from a High-Altitude Community from Tucumán Province, Argentina. Remarkable Low Detection of Soil-Transmitted Helminths in Comparison with Coastal Communities

The prevalence of intestinal parasitic infections among schoolchildren in Colalao del Valle, a high-altitude community in Tucumán province, Argentina, was investigated. The data revealed a high prevalence of parasitism (79.7%) with no significant differences in distribution by sex or age. Protozoa infections were the most common with Blastocystis hominis being the most prevalent (62.5%), followed by Giardia lamblia (29.7%), Endolimax nana (15.6%), Entamoeba coli (12.5%) and Iodamoeba bustchili (3.1%). Interestingly, there was an absence of soil-transmitted helminths among the studied population which could be related to climate (variable temperatures, moderate rainfall) and soil type (clay).Fil: Dib, Julian Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Fernandez Zenoff, Maria Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Oquilla, Juana del Valle. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Rudelli, M.. Ministerio de Salud de la Nación; ArgentinaFil: Lazarte, S.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Gonzalez, Silvia Nelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

Stereospecificity of pig liver esterase in the hydrolysis of racemic esters derived from 1,8-cineole

The efficient synthesis of biological active compounds, so much natural as not natural, frequently requires chiral syntons. Enzymes as chiral catalysts are widely used for this purpose owing to the fact that it is usually difficult to carry out highly enantioselective transformations using chemical methods. Esterases, such as that of pig liver (PLE), a serine hydrolase, is able to hydrolize a wide range of substrates with high stereoselectivity. This enzyme has been used for the hydrolysis of different esters, mainly meso and prochiral diesters. 1,8-cineole (1) or eucalyptol is a bicyclic monoterpene ether widespread in plant kingdom (Fig. 1). This is the main constituent of a number of essential oils, in particular those produced by several species of the genus Eucaliptus. We selected the racemates of acetates 5a and 6a, and the diacetate 6b with the purpose of studying the specificity of PLE and its utility for preparing pure enantiomers.   Our results indicate that the enzyme is effective for the enantioselective hydrolysis of the racemate of 5a. However, it doesn´t discriminate the racemate of the primary acetate 6a. The results of the hydrolysis of the diacetate 6b analysed after 3 hours incubation gave a 1:1 mixture of the hydroxyacetate 7b and diol 8, remaining approximately 60% of the unaffected diacetate.  On the other hand, this method represents a route of easy access to 7b, which is almost impossible to obtain by acetylation of the corresponding alcohol, and for obtaining pure enantiomers of 3a.Fil: Loandos, Maria del Huerto. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Muro, Ana Carolina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Villecco, Margarita Beatriz. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Catalan, Cesar Atilio Nazareno. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin