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91.
In order to study the composition of the lactic acid bacteria (LAB) community of sourdoughs used for the manufacture of Altamura bread, a traditional durum wheat bread produced in Apulia (Southern Italy), 111 strains of LAB were isolated and characterized. The phenotypic characterization of the isolates, carried out using a set of 29 tests, allowed the identification of 15 clusters at the 80% similarity level by hierarchical cluster analysis. Of the isolates, 88% were identified as facultatively heterofermentative LAB (Lactobacillus plantarum, Lb. paracasei, Lb. casei) and 12% as heterofermentative LAB (Lb. brevis, Leuconostoc mesenteroides). SDS-PAGE profiles of whole cell proteins of 68 strains confirmed the identification. Both the diversity and structure of the lactic microflora for sourdoughs for Altamura bread varied among samples.  相似文献   
92.
Notwithstanding the existence of a broad research base on assembly line balancing (ALB), companies do not use the mathematical approaches developed in the literature to configure assembly lines. This article aims to fill the gap between research and application by presenting and testing in a real industrial context a methodology based on complexity reduction and kaizen events. First, the methodology supports reducing the complexity that affects real-life assembly systems in terms of the variety of, e.g. finished products, materials and parts. Next, the methodology proposes the conduction of kaizen events by using lean manufacturing tools, such as process analysis, time observation, waste identification, workstation standard documents and yamazumi charts. The methodology is successfully applied to a case study that describes its use in the confectionery process for a major chocolatier company along with the results of the application. The main contribution of this paper consists in presenting a method to manage the line balancing activity within everyday industrial realities, helping practitioners to improve and maintain the performance over time.  相似文献   
93.
94.
The antioxidant properties of nine different samples of freshly drawn, pasteurised and UHT milk were examined before and after fermentation with several lactobacilli, individually and in combination with the yeast Saccharomyces boulardii. The results showed no statistical differences for the content in proteins, fats and carbohydrates of the different milk. The antioxidant properties of the unfermented milk were positively affected by the thermal treatment. All samples of fermented milk had a greater antioxidant activity than unfermented but only for the freshly drawn milk that increase was significantly different. The co‐incubation of lactobacilli with the yeast determined a stronger antioxidant activity especially for the freshly drawn milk. The stability of the tested strains during storage in standard conditions was determined in UHT fermented milk to enable a possible use in probiotic food production. The results showed that the yeast incubated with lactobacilli determined an improvement of the viability of bacteria.  相似文献   
95.
The aim of this work was to study the influence of hen age and housing system on egg performances in fresh pasta production, focusing on mechanical and rheological properties of pasta. Samples of pasta were prepared with eggs laid by Hy‐Line Brown hens (from 27 to 68 weeks old) housed in conventional cage, barn and organic systems. Only hen age significantly affected pasta properties. In particular, as regards raw pasta, the loosest structure was obtained using eggs laid by the youngest hens (27–30 weeks old). On the contrary, in cooked pasta, the weakest structure was observed when eggs were laid by hens aged 53–68 weeks. However, differences, although significant, were small and thus most likely not sensorially perceivable. Significant correlations were found between mechanical and rheological properties of raw fresh egg pasta, meaning that small deformation measurements are as valuable as large deformation tests for the characterisation of this product.  相似文献   
96.
COVID-19 is a global threat that has spread since the end of 2019, causing severe clinical sequelae and deaths, in the context of a world pandemic. The infection of the highly pathogenetic and infectious SARS-CoV-2 coronavirus has been proven to exert systemic effects impacting the metabolism. Yet, the metabolic pathways involved in the pathophysiology and progression of COVID-19 are still unclear. Here, we present the results of a mass spectrometry-based targeted metabolomic analysis on a cohort of 52 hospitalized COVID-19 patients, classified according to disease severity as mild, moderate, and severe. Our analysis defines a clear signature of COVID-19 that includes increased serum levels of lactic acid in all the forms of the disease. Pathway analysis revealed dysregulation of energy production and amino acid metabolism. Globally, the variations found in the serum metabolome of COVID-19 patients may reflect a more complex systemic perturbation induced by SARS-CoV-2, possibly affecting carbon and nitrogen liver metabolism.  相似文献   
97.
Four novel straight-chain polyacetylenic alcohols were isolated from a marine ascidian (Phylum Chordata, subphyllum Urochordata) collected off Vigo, along the Atlantic coast of northwestern Spain. The chemical structures, which exhibit an uncommon dienyne group, were characterized by spectroscopic methods, mainly mono- and bi-dimensional NMR. This is the first finding of acetylenic lipids from an organism belonging to phylum Chordata.  相似文献   
98.
99.
Toxic and genotoxic evaluation of six antibiotics on non-target organisms   总被引:10,自引:0,他引:10  
The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin. Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS Chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding their occurrence in the aquatic environment and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of microg/L, mainly for the algae. Drugs investigated were one or two order of magnitude less active against rotifers and crustaceans. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment.  相似文献   
100.
Honey is a valuable food produced by bees from sugary substances that they gather in nature. The transformation the nectar into honey, by bees, is long and complex. Except for honey, where heavy metals are absent or are found only in traces, the bees and their products have always been considered excellent biomarkers of such contaminants. We have assumed that the absence of heavy metals in honey is due to the presence of a detoxification system in the digestive system of bees, which involves metallothioneins, proteins that have a role in the homeostatic control of essential and non‐essential metals. We have placed the beehives in three different zones: industrial, urban and rural. Investigations were carried out with ICP‐MS method for the detection of heavy metals in the guts of honey bees and honey. The metallothioneins have been identified by Immunohistochemical and Western‐blotting analisys. The investigations have shown the presence of heavy metals only in bees guts but not in honey, while the presence of metallothionein has been highlighted only in epithelium of the honey sac, demonstrating the existence of an efficient system of detoxification of heavy metals.  相似文献   
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