36 research outputs found

    Codominance of Lactobacillus plantarum and obligate heterofermentative lactic acid bacteria during sourdough fermentation

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    Fifteen sourdoughs produced in western Sicily (southern Italy) were analysed by classical methods for their chemico-physical characteristics and the levels of lactic acid bacteria (LAB). pH and total titratable acidity (TTA) were mostly in the range commonly reported for similar products produced in Italy, but the fermentation quotient (FQ) of the majority of samples was above 4.0, due to the low concentration of acetic acid estimated by high performance liquid chromatography (HPLC). Specific counts of LAB showed levels higher than 108CFUg-1 for many samples. The colonies representing various morphologies were isolated and, after the differentiation based on phenotypic characteristics, divided into 10 groups. The most numerous group was composed of facultative heterofermentative isolates, indicating a relevance of this bacterial group during fermentation. The genetic analysis by randomly amplified polymorphic DNA (RAPD)-PCR, 16S rRNA gene sequencing and species-specific PCRs identified 33 strains as Lactobacillus plantarum, Lactobacillus curvatus and Lactobacillus graminis. Due to the consistent presence of L.plantarum, it was concluded that this species codominates with obligate heterofermentative LAB in sourdough production in this geographical area. In order to evaluate the performances at the basis of their fitness, the 29 L.plantarum strains were investigated for several technological traits. Twelve cultures showed good acidifying abilities invitro and L.plantarum PON100148 produced the highest concentrations of organic acids. Eleven strains were positive for extracellular protease activity. Bacteriocin-like inhibitory substances (BLIS) production and antifungal activity was scored positive for several strains, included L.plantarum PON100148 which was selected as starter for experimental sourdough production. The characteristics of the sourdoughs and the resulting breads indicated that the best productions were obtained in presence of L.plantarum PON100148

    Industrial application of selected lactic acid bacteria isolated from local semolinas for typical sourdough bread production

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    Four obligate heterofermentative lactic acid bacteria (LAB) strains (Weissella cibaria PON10030 and PON10032 and Leuconostoc citreum PON 10079 and PON10080) were tested as single strain starters, mono-species dual strain starters, and multiple strain starter for the preparation and propagation of sourdoughs for the production of a typical bread at industrial level. The kinetics of pH and TTA during the daily sourdough refreshments indicated a correct acidification process for all trials. The concentration of lactic and acetic acid increased consistently during fermentation. The resulting molar ratios between these two organic acids in the experimental trials were lower than those observed in the control trial. The microbiological investigation showed levels of approximately 109 CFU/mL in almost all sourdoughs and the comparison of the genetic polymorphisms of the dominating LAB with those of the pure cultures evidenced the persistence of the added strains over time. The resulting breads were evaluated for several quality parameters. The breads with the greatest height were obtained with the quadruple combination of leuconostocs and weissellas. The highest softness was registered for the breads obtained from fermentations performed by W. cibaria PON10032 alone and in combination. The different inocula influenced also the color, the void fraction, the cell density and the mean cell area of the breads. Different levels of acids, alcohols, aldehydes, esters, hydrocarbons, ketones, terpenes, furans and phenol were emitted by the breads. The sensory tests indicated the breads from the sourdoughs fermented with the seven LAB inocula as sweeter and less acidic than control breads and the breads from the trials with the highest complexity of LAB inoculums were those more appreciated by tasters. A multivariate approach found strong differences among the trials. In particular, control breads and the breads obtained with different starter LAB were quite distant and a more strict relation was found among the productions carried out by W. cibaria strains. This study proved the suitability of the selected strains of L. citreum and W. cibaria for industrial-scale level applications in sourdough bread production

    Diversity and technological potential of lactic acid bacteria of wheat flours

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    Lactic acid bacteria (LAB) were analysed from wheat flours used in traditional bread making throughout Sicily (southern Italy). Plate counts, carried out in three different media commonly used to detect food and sourdough LAB, revealed a maximal LAB concentration of approximately 4.75 Log CFU g 1. Colonies representing various morphological appearances were isolated and differentiated based on phenotypic characteristics and genetic analysis by randomly amplified polymorphic DNA (RAPD)-PCR. Fifty unique strains were identified. Analysis by 16S rRNA gene sequencing grouped the strains into 11 LAB species, which belonged to six genera: Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus and Weissella. Weissella cibaria, Lactobacillus plantarum, Leuconostoc pseudomesenteroides and Leuconostoc citreum were the most prevalent species. The strains were not geographically related. Denaturing gradient gel electrophoresis (DGGE) analysis of total DNA of flour was used to provide a more complete understanding of the LAB population; it confirmed the presence of species identified with the culturedependent approach, but did not reveal the presence of any additional LAB species. Finally, the technological characteristics (acidifying capacity, antimicrobial production, proteolytic activity, organic acid, and volatile organic compound generation) of the 50 LAB strains were investigated. Eleven strains were selected for future in situ applications

    Potencial de rendimento da soja em razão da disponibilidade de fósforo no solo e dos espaçamentos

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    The experiment was performed during the 1994/95 growing season at the EEA/UFRGS, in Eldorado do Sul, RS, Brazil, in a dark red Podzolic soil (Rhodic Paleudult). The objective was to evaluate the soybean potential yield at the growth stages R2 (flowering), R5 (beginning of pod filling) and R8 (maturity). The treatments were arranged in subplots in a randomized complete block design, and consisted of two soil P levels (3 and 15 ppm), and two row spacings (20 and 40 cm). The early, determinate cultivar OCEPAR 14 was used. On the average of the treatments, potential yield in R2 was of 18 t/ha and of 10 t/ha in R5, and the final yield, in R8 of 4.6 t/ha. The treatment of 15 ppm of P reached greater potential yield in the three growth stages, due to less flower and pod abortion. The row spacing of 20 cm showed greater potential yield at the growth stages evaluated, but the percentage of yield reduction due to flower and pod abortion were similar.O objetivo deste trabalho foi avaliar o potencial produtivo de grãos da soja nos estádios fenológicos R2 (florescimento), R5 (início de enchimento de grãos) e R8 (maturação). O experimento foi conduzido durante o ano agrícola 1994/95 na EEA/UFRGS, Eldorado do Sul, RS, em solo Podzólico Vermelho-Escuro (Paleudult). O delineamento utilizado foi o de blocos casualizados, com quatro repetições, com os tratamentos arranjados em parcelas subdivididas. Os tratamentos originaram-se da combinação de dois níveis de P no solo (3 e 15 ppm), e dois espaçamentos entre linhas (20 e 40 cm). Foi utilizada a cultivar precoce, determinada, OCEPAR 14. Na média dos tratamentos, o potencial de rendimento alcançado em R2 foi de 18 t/ha e de 10 t/ha em R5, sendo o rendimento obtido em R8 de 4,6 t/ha. O tratamento com 15 ppm de P apresentou maior potencial de rendimento, nos três estádios fenológicos, em decorrência do menor aborto de flores e de legumes. O espaçamento de 20 cm entre linhas apresentou maior potencial que o de 40 cm nos três estádios fenológicos avaliados, mas os valores percentuais de diminuição do rendimento pelo aborto de flores e de legumes foram similares

    Clinical value of radiomics and machine learning in breast ultrasound: a multicenter study for differential diagnosis of benign and malignant lesions

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    We aimed to assess the performance of radiomics and machine learning (ML) for classification of non-cystic benign and malignant breast lesions on ultrasound images, compare ML's accuracy with that of a breast radiologist, and verify if the radiologist's performance is improved by using ML

    Predicting soil test phosphorus decrease in non-P-fertilized conditions

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    Monitoring the availability of phosphorus (P) in soil under continuous cropping facilitates finding deficiency in crops and contributes to improving crop growth and nutrient management models. Soil P availability for crops is usually estimated by soil test P (STP), such as Bray-1. This is widely used in the Americas. The relationship between the decrease of STP Bray-1 and cumulative removal of P was evaluated in non-P-fertilized areas in long-term studies. This removal was the sum of annual P removal over the study period as P exported in grains/crop outside the soil. The objectives were to: (a) quantify changes in STP as a function of cumulative P removal, (b) assess the relationship between relative decrease rate of STP and soil variables as well as annual removal of P by crops, and (c) develop a model to predict decrease of STP Bray-1. Exponential decay functions were used to describe annual cumulative removal of P and STP from soil over time for 12 long-term studies where no addition of P fertilizer was carried out. Changes in the relative rate of decrease of STP, relative to the initial STP Bray-1 value at the onset of the experiment, were predicted by the ratio of soil organic matter to clay and silt and the average annual P removal by exponential decay (R2adj = 0.64; RMSE = 3.2 mg kg−1). We propose this predictive model as suitable to provide estimates of the relative decrease rate of STP by Bray-1 and thereby improve management of P for optimizing crop yield. Highlights: STP Bray-1 decrease and cumulative P removal were related by exponential decay functions. Relative decrease rate of STP Bray-1 was related to SOM/(clay+silt) ratio and annual P removal. A predictive model of the relative decrease rate of STP Bray-1 was fitted and validate. Our model is a useful tool to help predict soil P availability and nutrient management.Fil: Appelhans, Stefania Carolina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; Argentina. Universidad Nacional de Entre Ríos; Argentina. Kansas State University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carciochi, Walter Daniel. Kansas State University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Correndo, Adrian. Kansas State University; Estados UnidosFil: Gutiérrez Boem, Flavio Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; ArgentinaFil: Salvagiotti, Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Oliveros; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garcia, Fernando Oscar. International Plant Nutrition Institute; ArgentinaFil: Melchiori, Ricardo J.M.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; ArgentinaFil: Barbagelata, Pedro Aníbal. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; Argentina. Universidad Nacional de Entre Ríos; ArgentinaFil: Ventimiglia, Luis A.. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Buenos Aires Norte. Estacion Experimental Agropecuaria Pergamino. Agencia de Extension Rural 9 de Julio.; ArgentinaFil: Ferraris, Gustavo Nestor. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Vivas, Hugo S.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Caviglia, Octavio Pedro. Universidad Nacional de Entre Ríos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ciampitti, Ignacio Antonio. Kansas State University; Estados Unido

    Cilento illustrato da Francesco Antonio Ventimiglia (1738-1822) barone di Messer Matteo e Moriglione. Socio Nazionale della R. A. di S. B. L. Tomo I

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    Cart., sec. XIX; cc. [54] numerate a pp. [2],106, mm. 310x210; bifogli e fascicoli rigati sciolti.La prima p. non numerata riporta, oltre a titolo e autore, in alto a destra lo stemma gentilizio dei Ventimiglia disegnato a penna e, sulla destra a tre quarti del foglio, quattro versi dalla Gerusalemme conquistata di Tasso (I, 63) a mo’ di exergon. Sul verso l’Indice dei Capitoli. Alle pp. 1-106, preceduto da un'Introduzione (pp. 1-3), è il testo del I Libro, con l’apparato in calce, vergato da un’unica mano. Note, correzioni e aggiunte interlineari sembrano eseguite con differenti inchiostri.Il ms. è copia dell’originale settecentesco e reca l’intero primo libro (capp. 1.-10.), che, unitamente al regesto del quinto ed ultimo, è tutto ciò che rimane dell’opera originaria.Ed. a stampa: Francesco Antonio Ventimiglia, Cilento illustrato. Con introduzione e a cura di Francesco Volpe. Napoli, Edizioni Scientifiche Italiane, 2003 (Quaderni di storia del Mezzogiorno, 23)Proviene dal Fondo Ventimiglia

    La civiltà del lavoro nel mondo giuridico : i codici Mussolini

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    - Introduzione generale #5- Diritto ed equità #15- I Codici Mussolini #45- Indice #19
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