scholarly journals Advances in the Study of Candida stellata

Fermentation ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 74 ◽  
Author(s):  
Margarita García ◽  
Braulio Esteve-Zarzoso ◽  
Juan Cabellos ◽  
Teresa Arroyo
Keyword(s):  
Chemical Characterization ◽  
Wine Aroma ◽  
Wine Quality ◽  
Starmerella Bombicola ◽  
Balsamic Vinegar ◽  
High Concentrations ◽  
Wine Flavor ◽  
The Individual ◽  
Candida Stellata

Candida stellata is an imperfect yeast of the genus Candida that belongs to the order Saccharomycetales, while phylum Ascomycota. C. stellata was isolated originally from a must overripe in Germany but is widespread in natural and artificial habitats. C. stellata is a yeast with a taxonomic history characterized by numerous changes; it is either a heterogeneous species or easily confused with other yeast species that colonize the same substrates. The strain DBVPG 3827, frequently used to investigate the oenological properties of C. stellata, was recently renamed as Starmerella bombicola, which can be easily confused with C. zemplinina or related species like C. lactis-condensi. Strains of C. stellata have been used in the processing of foods and feeds for thousands of years. This species, which is commonly isolated from grape must, has been found to be competitive and persistent in fermentation in both white and red wine in various wine regions of the world and tolerates a concentration of at least 9% (v/v) ethanol. Although these yeasts can produce spoilage, several studies have been conducted to characterize C. stellata for their ability to produce desirable metabolites for wine flavor, such as acetate esters, or for the presence of enzymatic activities that enhance wine aroma, such as β-glucosidase. This microorganism could also possess many interesting technological properties that could be applied in food processing. Exo and endoglucosidases and polygalactosidase of C. stellata are important in the degradation of β-glucans produced by Botrytis cinerea. In traditional balsamic vinegar production, C. stellata shapes the aromatic profile of traditional vinegar, producing ethanol from fructose and high concentrations of glycerol, succinic acid, ethyl acetate, and acetoin. Chemical characterization of exocellular polysaccharides produced by non-Saccharomyces yeasts revealed them to essentially be mannoproteins with high mannose contents, ranging from 73–74% for Starmerella bombicola. Numerous studies have clearly proven that these macromolecules make multiple positive contributions to wine quality. Recent studies on C. stellata strains in wines made by co-fermentation with Saccharomyces cerevisiae have found that the aroma attributes of the individual strains were apparent when the inoculation protocol permitted the growth and activity of both yeasts. The exploitation of the diversity of biochemical and sensory properties of non-Saccharomyces yeast could be of interest for obtaining new products.

Preparation and Characterization of a Calcium Phosphate Ceramic for the Immobilization of Chloride-containing Intermediate Level Waste

2002 ◽  
Vol 757 ◽  
Author(s):  
Brian L. Metcalfe ◽  
Ian W. Donald ◽  
Randy D. Scheele ◽  
Denis M. Strachan
Keyword(s):  
Calcium Phosphate ◽  
Rate Data ◽  
Volatile Species ◽  
Calcium Phosphate Ceramic ◽  
Radioactive Materials ◽  
Mineral Phases ◽  
Simulated Waste ◽  
High Concentrations ◽  
The Individual

ABSTRACTAttention has recently been given to the immobilization of special categories of radioactive wastes, some of which contain high concentrations of actinide chlorides. Although vitrification in phosphate glass has been proposed, this was rejected because of the high losses of chloride through the mobilization of volatile species.On the basis of non-radioactive and, more recently, radioactive studies, we have shown that calcium phosphate is an effective host for immobilizing the chloride constituents [1]. In this instance, the chlorine is retained as chloride, rather than evolved as a chlorine-bearing gas. The immobilized product is in the form of a free-flowing, non-hygroscopic powder, in which the chlorides are chemically combined within the synthetic mineral phases chlorapatite [Ca5(PO4)3Cl] and spodiosite [Ca2(PO4)Cl]. Data from studies on non-radioactive simulated waste consisting of a mixture of CaCl2 and SmCl3, and radioactive simulated waste composed of CaCl2 with PuCl3 or PuCl3 and AmCl3, are presented and compared.The XRD data confirm the presence of chlorapatite and spodiosite in the non-radioactive and radioactive materials. The durability of all specimens was measured with a modified MCC-1 test. Normalized releases of Cl after 28 days were 1.6 × 10-3 g m-2 for the non-radioactive specimens and 7 × 10-3 g m-2 for the Pu bearing specimens. Releases of Ca after 28 days were 0.3 × 10-3 and 2.0 × 10-3 g m-2 for the non-radioactive composition and the Pu composition, respectively, whilst release of Pu from the radioactive specimens was higher for the mixed Pu/Am specimen at 1.2 × 10-5g m-2 than for the Pu only specimens. The release of Am from the mixed Pu/Am composition was exceptionally low at 2.4 × 10-7 g m-2. Overall, the release rate data suggest that the ceramics dissolve congruently, followed by precipitation of Sm, Pu and Am as less soluble phases, possibly oxides or phosphates. The differences in behaviour noted between non-radioactive and radioactive specimens are interpreted in terms of the crystal chemistry of the individual systems.

scholarly journals Chemical Characterization Of Commercial Balsamic Vinegar Glaze

2020 ◽  
Vol 94 ◽  
pp. 103620
Author(s):  
Lisa Lancellotti ◽  
Alessandro Ulrici ◽  
Simona Sighinolfi ◽  
Andrea Marchetti
Keyword(s):  
Chemical Characterization ◽  
Balsamic Vinegar

scholarly journals Chemical characterization of PM10 in two small towns located in South Poland

Nukleonika ◽  
2021 ◽  
Vol 66 (1) ◽  
pp. 29-34
Author(s):  
Anna Turek-Fijak ◽  
Joanna Brania ◽  
Katarzyna Styszko ◽  
Damian Zięba ◽  
Zdzisław Stęgowski ◽  
...  
Keyword(s):  
Fossil Fuels ◽  
Chemical Elements ◽  
Chemical Characterization ◽  
Small Towns ◽  
Ray Method ◽  
Air Samples ◽  
X Ray ◽  
Limit Value ◽  
High Concentrations

Abstract The purpose of this study is to analyse the elements and PM10 concentrations in air samples gathered in the winter of 2017/2018 in two small towns, namely Skala and Wadowice. The chemical elements were identified for each sample using the energy dispersive X-ray method. The spectrometer was equipped, among others, with an Mo-X-ray tube which was the source of the photons and the Si(Li) detector. The following chemical elements: Cl, K, Fe, Ca, Zn, Pb, Br, Ti, Cu, Mn, V, Co, Rb, Ni, Sr, and Cr were identified in the samples. In addition, As and Se were identified in Wadowice. First, the results were compared with each other and then with the results for the nearest city. It was observed that the PM10 concentrations were significantly higher than the UE limit value for PM10, which equals 50 μg·m−3 per 24 h. Moreover, the high concentrations of, among others, K, Pb, Cl or Zn, are likely to be linked with fossil fuels combustion and biomass burning. The levels of element concentrations in Wadowice and Skala resemble the levels observed several years earlier in Krakow.

scholarly journals Characterization of non-refractory (NR) PM<sub>1</sub> and source apportionment of organic aerosol in Kraków, Poland

2021 ◽  
Vol 21 (19) ◽  
pp. 14893-14906
Author(s):  
Anna K. Tobler ◽  
Alicja Skiba ◽  
Francesco Canonaco ◽  
Griša Močnik ◽  
Pragati Rai ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Chemical Characterization ◽  
Organic Aerosol ◽  
Pollution Levels ◽  
Full Dataset ◽  
Residential Heating ◽  
Solid Fuel Combustion ◽  
High Concentrations

Abstract. Kraków is routinely affected by very high air pollution levels, especially during the winter months. Although a lot of effort has been made to characterize ambient aerosol, there is a lack of online and long-term measurements of non-refractory aerosol. Our measurements at the AGH University of Science and Technology provide the online long-term chemical composition of ambient submicron particulate matter (PM1) between January 2018 and April 2019. Here we report the chemical characterization of non-refractory submicron aerosol and source apportionment of the organic fraction by positive matrix factorization (PMF). In contrast to other long-term source apportionment studies, we let a small PMF window roll over the dataset instead of performing PMF over the full dataset or on separate seasons. In this way, the seasonal variation in the source profiles can be captured. The uncertainties in the PMF solutions are addressed by the bootstrap resampling strategy and the random a-value approach for constrained factors. We observe clear seasonal patterns in the concentration and composition of PM1, with high concentrations during the winter months and lower concentrations during the summer months. Organics are the dominant species throughout the campaign. Five organic aerosol (OA) factors are resolved, of which three are of a primary nature (hydrocarbon-like OA (HOA), biomass burning OA (BBOA) and coal combustion OA (CCOA)) and two are of a secondary nature (more oxidized oxygenated OA (MO-OOA) and less oxidized oxygenated OA (LO-OOA)). While HOA contributes on average 8.6 % ± 2.3 % throughout the campaign, the solid-fuel-combustion-related BBOA and CCOA show a clear seasonal trend with average contributions of 10.4 % ± 2.7 % and 14.1 %, ±2.1 %, respectively. Not only BBOA but also CCOA is associated with residential heating because of the pronounced yearly cycle where the highest contributions are observed during wintertime. Throughout the campaign, the OOA can be separated into MO-OOA and LO-OOA with average contributions of 38.4 % ± 8.4 % and 28.5 % ± 11.2 %, respectively.

scholarly journals Influence of Triazole Pesticides on Wine Flavor and Quality Based on Multidimensional Analysis Technology

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5596
Author(s):  
Ouli Xiao ◽  
Minmin Li ◽  
Jieyin Chen ◽  
Ruixing Li ◽  
Rui Quan ◽  
...  
Keyword(s):  
Pesticide Residues ◽  
Solid Phase ◽  
Negative Influence ◽  
Multidimensional Analysis ◽  
Yeast Fermentation ◽  
Wine Aroma ◽  
Wine Quality ◽  
Wine Flavor ◽  
Fruit Flavor ◽  
The Impact

Triazole pesticides are widely used to control grapevine diseases. In this study, we investigated the impact of three triazole pesticides—triadimefon, tebuconazole, and paclobutrazol—on the concentrations of wine aroma compounds. All three triazole pesticides significantly affected the ester and acid aroma components. Among them, paclobutrazol exhibited the greatest negative influence on the wine aroma quality through its effect on the ester and acid aroma substances, followed by tebuconazole and triadimefon. Qualitative and quantitative analysis by solid-phase micro-extraction gas chromatography coupled with mass spectrometry revealed that the triazole pesticides also changed the flower and fruit flavor component contents of the wines. This was attributed to changes in the yeast fermentation activity caused by the pesticide residues. The study reveals that triazole pesticides negatively impact on the volatile composition of wines with a potential undesirable effect on wine quality, underlining the desirability of stricter control by the food industry over pesticide residues in winemaking.

Rheological and Chemical Characterization of Smoothie Beverages Containing High Concentrations of Fibre and Polyphenols from Apple

2013 ◽  
Vol 7 (2) ◽  
pp. 409-423 ◽  
Author(s):  
Dongxiao Sun-Waterhouse ◽  
Karim Bekkour ◽  
Sandhya S. Wadhwa ◽  
Geoffrey I.N. Waterhouse
Keyword(s):  
Chemical Characterization ◽  
High Concentrations

scholarly journals Microbial and Chemical Analysis of Non-Saccharomyces Yeasts from Chambourcin Hybrid Grapes for Potential Use in Winemaking

Fermentation ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 15
Author(s):  
Chun Tang Feng ◽  
Xue Du ◽  
Josephine Wee
Keyword(s):  
Chemical Characterization ◽  
Fungal Species ◽  
Its Sequencing ◽  
Wine Quality ◽  
Cold Temperatures ◽  
Hanseniaspora Uvarum ◽  
Floral Odor ◽  
Wine Flavor ◽  
Pichia Kluyveri ◽  
Saccharomyces Yeasts

Native microorganisms present on grapes can influence final wine quality. Chambourcin is the most abundant hybrid grape grown in Pennsylvania and is more resistant to cold temperatures and fungal diseases compared to Vitis vinifera. Here, non-Saccharomyces yeasts were isolated from spontaneously fermenting Chambourcin must from three regional vineyards. Using cultured-based methods and ITS sequencing, Hanseniaspora and Pichia spp. were the most dominant genus out of 29 fungal species identified. Five strains of Hanseniaspora uvarum, H. opuntiae, Pichia kluyveri, P. kudriavzevii, and Aureobasidium pullulans were characterized for the ability to tolerate sulfite and ethanol. Hanseniaspora opuntiae PSWCC64 and P. kudriavzevii PSWCC102 can tolerate 8–10% ethanol and were able to utilize 60–80% sugars during fermentation. Laboratory scale fermentations of candidate strain into sterile Chambourcin juice allowed for analyzing compounds associated with wine flavor. Nine nonvolatile compounds were conserved in inoculated fermentations. In contrast, Hanseniaspora strains PSWCC64 and PSWCC70 were positively correlated with 2-heptanol and ionone associated to fruity and floral odor and P. kudriazevii PSWCC102 was positively correlated with a group of esters and acetals associated to fruity and herbaceous aroma. Microbial and chemical characterization of non-Saccharomyces yeasts presents an exciting approach to enhance flavor complexity and regionality of hybrid wines.

scholarly journals Chemical Composition of PM10 in 16 Urban, Industrial and Background Sites in Italy

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 479 ◽  
Author(s):  
Cinzia Perrino ◽  
Maria Catrambone ◽  
Silvia Canepari
Keyword(s):  
Chemical Composition ◽  
Chemical Characterization ◽  
Principal Component ◽  
Industrial Plants ◽  
Variable Configuration ◽  
The Individual ◽  
The Relationship ◽  
Pm10 Mass ◽  
Italian Territory

Italy is characterized by a very variable configuration in terms of altitude, proximity to the sea, latitude and the presence of industrial plants. This paper summarizes the chemical characterization of PM10 obtained from 38 sampling campaigns carried out in 16 sites in Italy during the years 2008–2018. Chemical determinations include all macro-components (six macro-elements, eight ions, elemental carbon and organic carbon). The sum of the individual components agrees well with the PM10 mass. The chemical composition of the atmospheric aerosol clearly reflects the variety in the Italian territory and the pronounced seasonal variations in the meteoclimatic conditions that characterize the country. Macro-sources reconstruction allowed us to identify and evaluate the strength of the main PM10 sources in different areas. On 10 sampling sites, the soluble and insoluble fractions of 23 minor and trace elements were also determined. Principal Component Analysis was applied to these data to highlight the relationship between the elemental composition of PM10 and the characteristics of the sampling sites.

scholarly journals Chemical characterization of craft Filuferru spirit from Sardinia, Italy

2018 ◽  
Author(s):  
Ilaria Langasco ◽  
Gavino Sanna ◽  
Marco Caredda ◽  
Angelo Panzanelli ◽  
Maria Itria Pilo ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Volatile Compounds ◽  
Chemical Characterization ◽  
Trace Element Composition ◽  
Qualitative And Quantitative ◽  
Wide Variability ◽  
High Concentrations ◽  
Alcoholic Strength

Traditional Filuferru is an ancient spirit from Sardinia, Italy, usually obtained from the distillation of wine or grape marc. In this contribution, the results of the first chemical characterization of a wide number of craft Filuferru samples has been accomplished in terms of evaluation of the alcoholic strength, qualitative and quantitative GC-MS analysis of the volatile composition of the distillate, and its trace element composition by means a ICP-MS method. Both instrumental methods have been validated and applied on 21 craft samples of Filuferru, whereas one sample of commercial distillate has been analyzed for comparison purposes. Alcoholic strength ranged between 41.0 and 62.4% (v/v). Sixty volatile compounds were identified and ten of them have been quantified. Analogies and differences with Grappa (i.e. the Italian distilled spirit most close to Filuferru) have been highlighted in the qualitative and quantitative profile of this matrix. Often meaningful amounts of acetaldehyde, ethyl acetate, dietyl acetal and acetic acid were measured. Elemental analysis, performed on toxic, non-toxic elements and oligoelements, 18 in total, revealed a wide variability of concentrations in both analytes and samples. High concentrations of Cu are sometimes evidenced, likely caused by losses from the distillation apparatus. The principal components analysis (PCA) allowed the differentiation of the ten volatile compounds quantified in two groups: the former, described mainly by PC1, constituted by acetic acid, ethyl acetate, dietyl acetal and acetaldehyde, and the second, described by PC2, constituted by 1-propanol, 2-methyl-1-propanol, the two coeluiting isomers 2-methyl-1-butanol and 3-methyl-1-butanol,1-hexanol, 2-phenylethanol and 2,3-butanediol. Data obtained may be useful in order to establish a regulation for the production of high-quality traditional Filuferru from Sardinia.

scholarly journals Characterization of NR-PM<sub>1</sub> and source apportionment of organic aerosol in Krakow, Poland

2021 ◽  
Author(s):  
Anna K. Tobler ◽  
Alicja Skiba ◽  
Francesco Canonaco ◽  
Griša Močnik ◽  
Pragati Rai ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Chemical Characterization ◽  
Organic Aerosol ◽  
Ambient Aerosols ◽  
Pollution Levels ◽  
Full Dataset ◽  
Solid Fuel Combustion ◽  
High Concentrations

Abstract. Krakow is routinely affected by very high air pollution levels, especially during the winter months. Although a lot of effort has been done on characterization of ambient aerosols, there is a lack of online and long-term measurements of non-refractory aerosols. Our measurements at AGH University provide online long-term chemical composition of ambient submicron particulate matter (PM1) between January 2018 and April 2019. Here we report the chemical characterization of non-refractory submicron aerosols and source apportionment of the organic fraction by positive matrix factorization (PMF). In contrast to other long-term source apportionment studies, we let a small PMF window roll over the dataset instead of performing PMF over the full dataset or on separate seasons. In this way, the seasonal variation of the source profiles can be captured. The uncertainties of the PMF solutions are addressed by the bootstrap resampling strategy and the random a-value approach for constrained factors.We observe clear seasonal patterns in concentration and composition of PM1, with high concentrations during the winter months and lower concentrations during the summer months. Organics are the dominant species throughout the campaign. Five organic aerosol (OA) factors are resolved, of which three are of primary nature (hydrocarbon-like OA (HOA), biomass burning OA (BBOA) and coal combustion OA (CCOA)) and two are of secondary nature (more oxidized oxygenated OA (MO-OOA) and less oxidized oxygenated OA (LO-OOA)). While HOA contributes on average 8.6 % ± 2.3 % throughout the campaign, the solid fuel combustion related BBOA and CCOA show a clear seasonal trend with average contributions of 10.4 % ± 2.7 % and 14.1 %, ± 2.1 % respectively. The highest contributions are observed during wintertime as a result of residential heating. Throughout the campaign, the OOA can be separated into MO-OOA and LO-OOA with average contribution of 38.4 % ± 8.4 % and 28.5 % ± 11.2 %, respectively.

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