Search results for "SAC"
showing 10 items of 3337 documents
Corrigendum: Flor Yeast Diversity and Dynamics in Biologically Aged Wines
2019
International audience; [This corrects the article DOI: 10.3389/fmicb.2018.02235.].
Insights Into the Cultivable Microbial Ecology of “Manna” Ash Products Extracted From Fraxinus angustifolia (Oleaceae) Trees in Sicily, Italy
2019
Microbial communities characterizing a specific food matrix, generally, strongly contribute to both its composition, and properties for food applications. To our knowledge, this is the first study to investigate the cultivable microbial ecology of Sicilian "Manna" ash products in order to acquire new information on the hygienic quality, shelf-life and potential application of this traditional food. To this purpose, several manna samples belonging to different commercial categories were collected and subjected to the analysis of bacteria, yeasts, and filamentous fungi. Furthermore, an investigation of the sugar content and physicochemical parameters was performed. The results of our study fo…
The Role of Yeasts in Fermentation Processes
2020
In recent years, vessels have been discovered that contain the remains of wine with an age close to 7000 years. It is unclear whether, in ancient times, humans accidentally stumbled across fermented beverages like wine or beer, or was it a product intended as such. What is a fact is that since then, alcoholic beverages have been part of the diet and culture of many of the civilizations that have preceded us. The typical examples of beer and wine are an example of many other drinks resulting from the action of yeasts. In addition to these two beverages, various companies have developed other types of fermented foods and non-alcoholic beverages prepared in a traditional or commercial manner. …
Extraction, Structural Characterisation, and Immunomodulatory Properties of Edible Amanita hemibapha subspecies javanica (Corner and Bas) Mucilage Po…
2021
This research aimed to extract mucilage polysaccharides (MP) from Amanita hemibapha subspecies javanica (Corner and Bas), and further fractionate them using anion-exchange chromatography, yielding two fractions (MPF1 and MPF2). The crude extract, and fractions mainly consisted of carbohydrates (83.5–93.2%) with minor amounts of proteins (5.40–7.20%), and sulphates (1.40–9.30%). Determination of the monosaccharide composition revealed that glucose was the major unit, followed by galactose, mannose, rhamnose, and arabinose. The average molecular weight (MW) of the crude extract and fractions was in the range 104.0–479.4 × 103 g/mol. Interestingly, the crude extract, and fractions did not caus…
Phylogenetic Distribution of Polysaccharide-Degrading Enzymes in Marine Bacteria
2021
Deconstruction is an essential step of conversion of polysaccharides, and polysaccharide-degrading enzymes play a key role in this process. Although there is recent progress in the identification of these enzymes, the diversity and phylogenetic distribution of these enzymes in marine microorganisms remain largely unknown, hindering our understanding of the ecological roles of marine microorganisms in the ocean carbon cycle. Here, we studied the phylogenetic distribution of nine types of polysaccharide-degrading enzymes in marine bacterial genomes. First, we manually compiled a reference sequence database containing 961 experimentally verified enzymes. With this reference database, we annota…
Different Modes of Regulation of the Expression of Dextransucrase in Leuconostoc lactis AV1n and Lactobacillus sakei MN1
2019
Leuconostoc lactis AV1 strain isolated from a Tunisian avocado was characterized as a dextran producer. The promoter PdsrLL and the dsrLL gene encoding the DsrLL dextransucrase responsible for the dextran synthesis were transcriptionally fused to the mCherry coding gene generating the pRCR20 plasmid. Upon plasmid transfer, both AV1n and the dextran non-producing Leuconostoc mesenteroides CM70 became red due to expression of the mCherry from the PdsrLL-dsr-mrfp transcriptional fusion. Characterization of the polymers present in cultures supernatants revealed that the DsrLL encoded from pRCR20 in the recombinant bacteria was able to synthesize dextran. The production of dextran by the DsrLL i…
Numbers Needed to Treat with Posaconazole Prophylaxis to Prevent Invasive Fungal Infection and Death
2008
Sulphation and Hydrolysis Improvements of Bioactivities, and Immuno-Modulatory Properties of Edible Amanita hemibapha Subspecies javanica (Corner and…
2021
In this study, the mucilage polysaccharide (MP) from Amanita hemibapha subspecies javanica was prepared by hot water extraction and ethanol precipitation and then fractionated using anion-exchange chromatography equipped with a DEAE Sepharose fast flow column. The most immune-enhancing polysaccharide fraction 2 (MPF2) was subjected to a structural modification such as hydrolysis or over-sulphation. The sulphate and molecular weight (Mw) of over-sulphated (OS1-3) and hydrolysed (HS1-3) derivatives of MPF2 differed between 9.85% and 14.2% and 32.8 and 88.1 × 103 g/mol, respectively. Further, the immune-enhancing properties of MPF2 and its derivatives were tested on RAW264.7 and NK cells throu…
An ACE Wholesale Electricity Market Framework with Bilateral Trading
2011
In this paper, an agent-based simulation model for a hybrid power market structure is presented. A bilateral transaction mechanism is combined with a uniform-pricing auction settlement in order to isolate the impact of medium-term bilateral contracts on market power and spot prices in a competitive wholesale market setting. First we describe the negotiation method for bilateral trading of energy and then introduce a new approach for bidding in the DA market based on the load duration curve. We find that, despite the conventional concerns, the foreclosure effect produced by the bilateral agreement between a generation and a retail business will not necessarily lead to higher prices, and will…
Yet Another Note on the Leland's Option Hedging Strategy with Transaction Costs
2005
In a market with transaction costs the option hedging is costly. The idea presented by Leland (1985) was to include the expected transaction costs in the cost of a replicating portfolio. The resulting Leland's pricing and hedging method is an adjusted Black-Scholes method where one uses a modified volatility in the Black-Scholes formulas for the option price and delta. The Leland's method has been criticized on different grounds. Despite the critique, the risk-return tradeoff of the Leland's strategy is often better than that of the Black-Scholes strategy even in the case when a hedger starts with the same initial value of a replicating portfolio. This implies that the Leland's modification…