Wickerhamomyces anomalus

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Cristina Restuccia - One of the best experts on this subject based on the ideXlab platform.

  • Role of biocontrol yeasts Debaryomyces hansenii and Wickerhamomyces anomalus in plants' defence mechanisms against Monilinia fructicola in apple fruits.
    Food Microbiology, 2019
    Co-Authors: Monika Czarnecka, Cristina Restuccia, Barbara Żarowska, X. Polomska, Gabriella Cirvilleri
    Abstract:

    The role of killer yeasts of the species Debaryomyces hansenii and Wickerhamomyces anomalus in biocontrol of Monilinia fructicola, and their involvement in plant defence mechanisms against brown rot in apple fruits, were investigated. D. hansenii KI2a and W. anomalus BS91 strains showed the highest in vitro biocontrol activity, inhibiting mycelium growth by 69.53% and 66.08% respectively, as compared to control fungal cultures. Brown rot on apple fruits was significantly reduced by BS91 and two strains of D. hansenii KI2a and AII4b by 92.46%, 85.10% and 70.02%, respectively, in comparison to infected fruits, which did not receive any pre-treatment. In enzymatic tests, the most significant changes in peroxidase (POD) and catalase (CAT) activities were observed in fruits inoculated either with BS91 followed by M. fructicola infection or with AII4b yeast strain alone, where POD activities were significantly higher by 67% and 54%, respectively, and CAT activities were significantly lower by 65% and 68%, respectively, than in untreated control fruits. These results confirmed the ability of killer yeasts to influence host-defence related enzyme activities in apple fruit tissue and may suggest that AII4b killer strain has a potential as biocontrol agent prior to infection by triggering immune response mechanisms in plant tissue, whereas BS91 strain is the most effective during pathogen infection and could be used as biocontrol agent in postharvest disease onset. Accordingly, the antagonistic strains of W. anomalus BS91 and D. hansenii KI2a and AII4b could be proposed as active ingredients for the development of biofungicide against M. fructicola.

  • Bioactivity Improvement of Olea europaea Leaf Extract Biotransformed by Wickerhamomyces anomalus Enzymes.
    Plant Foods for Human Nutrition, 2017
    Co-Authors: Rosa Palmeri, Cristina Restuccia, Julieta Ines Monteleone, Elisa Sperlinga, Laura Siracusa, Mauro Serafini, Alberto Finamore, Giovanni Spagna
    Abstract:

    Olive leaves represent a quantitatively significant by-product of agroindustry. They are rich in phenols, mainly oleuropein, which can be hydrolyzed into several bioactive compounds, including hydroxytyrosol. In this study, water extract from olive leaves ‘Biancolilla’ was analyzed for polyphenol profile, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and protective effect on differentiated Caco-2 cells. The efficacy of two enzymatic treatments in promoting the release of bioactive phenols was investigated: a) enzymatic extract from Wickerhamomyces anomalus, characterized by β-glucosidase and esterase activities; b) commercial β-glucosidase. Composition and bioactivity of the resulting extracts were compared. The results showed that the yeast-treated extract presented hydroxytyrosol content and DPPH radical scavenging activity comparable to those obtained using commercial β-glucosidase; however, it was showed the additional presence of hydroxycinnamic acids. In experiments on Caco-2 cells, the leaf extracts promoted the recovery of cell membrane barrier at different minimum effective concentrations. The high specificity of W. anomalus enzymatic extract may represent an effective tool for the release of bioactive phenols from olive by-products.

  • Potential Role of Exoglucanase Genes (WaEXG1 and WaEXG2) in the Biocontrol Activity of Wickerhamomyces anomalus
    Microbial Ecology, 2017
    Co-Authors: Lucia Parafati, Gabriella Cirvilleri, Cristina Restuccia
    Abstract:

    The use of yeasts, including Wickerhamomyces anomalus, as biocontrol agents of fungi responsible for postharvest diseases of fruits and vegetables has been investigated for the past two decades. Among a variety of mechanisms, the production of glucanases coded by the “killer genes” WaEXG1 and WaEXG2 have been reported to play a role in the ability of yeast to inhibit other fungi. The objective of the present study was to determine the expression of these genes by RT-qPCR, utilizing gene-specific primers, when W. anomalus was grown on grape berries and oranges that were either non-inoculated or inoculated with Botrytis cinerea or Penicillium digitatum, or in minimal media supplemented with cell walls of various plant pathogens and different amounts of glucose. Results indicated that WaEXG2 was more responsive than WaEXG1 to the nutritional environment (including the addition of glucose to cell wall-amended media) in vitro and appeared to play a greater role in the cellular metabolism of W. anomalus. WaEXG2 expression also appeared to be more responsive to the presence of cell walls of P. digitatum and B. cinerea than other fungal species, whereas the same level of induction was not seen in vivo when the yeast was grown in wounded/pathogen-inoculated fruits.

  • physical properties and antifungal activity of bioactive films containing Wickerhamomyces anomalus killer yeast and their application for preservation of oranges and control of postharvest green mold caused by penicillium digitatum
    International Journal of Food Microbiology, 2015
    Co-Authors: Hajer Aloui, Fabio Licciardello, Khaoula Khwaldia, Moktar Hamdi, Cristina Restuccia
    Abstract:

    Abstract This study assessed the ability of two bio-based films, obtained from sodium alginate (NaAlg) and locust bean gum (LBG), to protect the viability of Wickerhamomyces anomalus cells and control the growth of Penicillium digitatum. The effect of microbial cell incorporation on physical properties of the developed films was evaluated in terms of barrier, mechanical and optical properties. Furthermore, the application of these two matrices as bioactive coatings was investigated in order to evaluate their efficacy in preserving the postharvest quality of ‘Valencia’ oranges and inhibiting the growth of P. digitatum on artificially inoculated fruits. Results showed that NaAlg and LBG films were able to maintain more than 85% of the initial W. anomalus yeast population and that the developed films incorporating the killer yeast completely inhibited the growth of P. digitatum in synthetic medium. Likewise, NaAlg and LBG coatings enriched with W. anomalus yeast were effective at reducing weight loss and maintaining firmness of ‘Valencia’ oranges during storage, and reduced green mold in inoculated fruits by more than 73% after 13 days.

  • Exoglucanase-encoding genes from three Wickerhamomyces anomalus killer strains isolated from olive brine.
    Yeast, 2012
    Co-Authors: Serena Muccilli, Cristina Restuccia, Sabrina Wemhoff, Friedhelm Meinhardt
    Abstract:

    Wickerhamomyces anomalus killer strains are important for fighting pathogenic yeasts and for controlling harmful yeasts and bacteria in the food industry. Targeted disruption of key genes in β-glucan synthesis of a sensitive Saccharomyces cerevisiae strain conferred resistance to the toxins of W. anomalus strains BS91, BCA15 and BCU24 isolated from olive brine. Competitive inhibition of the killing activities by laminarin and pustulan refer to β-1,3- and β-1,6-glucans as the main primary toxin targets. The extracellular exoglucanase-encoding genes WaEXG1 and WaEXG2 from the three strains were sequenced and were found to display noticeable similarities to those from known potent W. anomalus killer strains. Accession Nos for WaEXG1 genes for the strains in brackets are JQ734563 (BS91), JQ734564 (BCA15) and JQ734565 (BCU24); for WaEXG2 genes JQ734566 (BS91), JQ734567 (BCA15) and JQ734568 (BCU24), respectively. Copyright © 2012 John Wiley & Sons, Ltd.

Irene Ricci - One of the best experts on this subject based on the ideXlab platform.

  • Candidacidal Activity of a Novel Killer Toxin from Wickerhamomyces anomalus against Fluconazole-Susceptible and -Resistant Strains
    Toxins, 2018
    Co-Authors: Laura Giovati, Irene Ricci, Sara Epis, Elena Martin, Claudia Santinoli, Elena Ferrari, Tecla Ciociola, Claudio Bandi, Stefania Conti
    Abstract:

    The isolation and characterization from the sand fly Phlebotomus perniciosus of a Wickerhamomyces anomalus yeast strain (Wa1F1) displaying the killer phenotype was recently reported. In the present work, the killer toxin (KT) produced by Wa1F1 was purified and characterized, and its antimicrobial activity in vitro was investigated against fluconazole- susceptible and -resistant clinical isolates and laboratory strains of Candida albicans and C. glabrata displaying known mutations. Wa1F1-KT showed a differential killing ability against different mutant strains of the same species. The results may be useful for the design of therapeutic molecules based on Wa1F1-KT and the study of yeast resistance mechanisms.

  • Isolation of a Wickerhamomyces anomalus yeast strain from the sandfly Phlebotomus perniciosus, displaying the killer phenotype
    Medical and Veterinary Entomology, 2015
    Co-Authors: Elena Martin, Irene Ricci, Laura Giovati, Gioia Bongiorno, Matteo Montagna, E.e Crotti, C.f Damiani, Luigi Gradoni, Luciano Polonelli, Guido Favia
    Abstract:

    The yeast Wickerhamomyces anomalus has been studied for its wide biotechnological potential, mainly for applications in the food industry. Different strains of W. anomalus have been isolated from diverse habitats and recently from insects, including mosquitoes of medical importance. This paper reports the isolation and phylogenetic characterization of W. anomalus from laboratory-reared adults and larvae of Phlebotomus perniciosus (Diptera: Psychodidae), a main phlebotomine vector of human and canine leishmaniasis. Of 65 yeast strains isolated from P. perniciosus, 15 strains were identified as W. anomalus; one of these was tested for the killer phenotype and demonstrated inhibitory activity against four yeast sensitive strains, as reported for mosquito-isolated strains. The association between P. perniciosus and W. anomalus deserves further investigation in order to explore the possibility that this yeast may exert inhibitory/killing activity against Leishmania spp.

  • A rapid qPCR method to investigate the circulation of the yeast Wickerhamomyces anomalus in humans.
    The new microbiologica, 2015
    Co-Authors: Sara Epis, Matteo Valzano, Guido Favia, Aida Capone, Elena Martin, Michela Paolucci, Chiara Bazzocchi, Jovana Bozic, Stefano Novati, Irene Ricci
    Abstract:

    The yeast Wickerhamomyces anomalus has been proposed for many biotechnological applications in the food industry. However, a number of opportunistic pathogenic strains have been reported as causative agents of nosocomial fungemia. Recognition of potentially pathogenic isolates is an important challenge for the future commercialization of this yeast. The isolation of W. anomalus from different matrices and, recently, from mosquitoes, requires further investigations into its circulation in humans. Here we present a qPCR protocol for the detection of W. anomalus in human blood samples and the results of a screening of 525 donors, including different classes of patients and healthy people.

  • The yeast Wickerhamomyces anomalus (Pichia anomala) inhabits the midgut and reproductive system of the Asian malaria vector Anopheles stephensi
    Environmental Microbiology, 2011
    Co-Authors: Irene Ricci, Claudia Damiani, Patrizia Scuppa, Michela Mosca, Elena Crotti, Paolo Rossi, Aurora Rizzi, Aida Capone, Elena Gonella, Patrizia Ballarini
    Abstract:

    Summary While symbiosis between bacteria and insects has been thoroughly investigated in the last two decades, investments on the study of yeasts associated with insects have been limited. Insect-associated yeasts are placed on different branches of the phylogenetic tree of fungi, indicating that these associations evolved independently on several occasions. Isola- tion of yeasts is frequently reported from insect habi- tats, and in some cases yeasts have been detected in the insect gut and in other organs/tissues. Here we show that the yeast Wickerhamomyces anomalus, previously known as Pichia anomala, is stably asso- ciated with the mosquito Anopheles stephensi ,a main vector of malaria in Asia. Wickerhamomyces anomalus colonized pre-adult stages (larvae L1-L4 and pupae) and adults of different sex and age and could be isolated in pure culture. By a combination of transmission electron microscopy and fluorescent in situ hybridization techniques, W. anomalus was shown to localize in the midgut and in both the male and female reproductive systems, suggesting mul- tiple transmission patterns.

  • Different mosquito species host Wickerhamomyces anomalus (Pichia anomala): perspectives on vector-borne diseases symbiotic control
    Antonie van Leeuwenhoek, 2011
    Co-Authors: Irene Ricci, Matteo Valzano, Alessia Cappelli, Claudia Damiani, Patrizia Scuppa, Michela Mosca, Elena Crotti, Paolo Rossi, Ulisse Ulissi, Aida Capone
    Abstract:

    The genetic manipulation of the microbial community associated with hematophagus insects is particularly relevant for public health applications. Within mosquito populations, this relationship has been overlooked until recently. New advances in molecular biotechnology propose the genetic manipulation of mosquito symbionts to prevent the transmission of pathogens to humans by interfering with the obligatory life cycle stages within the insect through the use of effector molecules. This approach, defined as ‘paratransgenesis’, has opened the way for the investigation and characterization of microbes residing in the mosquito body, particularly those localised within the gut. Some interesting bacteria have been identified as candidates for genetic modification, however, endosymbiotic yeasts remain largely unexplored with little information on the symbiotic relationships to date. Here we review the recent report of symbiotic relationship between Wickerhamomyces anomalus ( Pichia anomala ) and several mosquito vector species as promising methods to implement control of mosquito-borne diseases.

Guido Favia - One of the best experts on this subject based on the ideXlab platform.

  • Identification of a Killer Toxin from Wickerhamomyces anomalus with β-Glucanase Activity.
    Toxins, 2019
    Co-Authors: Valentina Cecarini, Massimiliano Cuccioloni, Laura Bonfili, Massimo Ricciutelli, Matteo Valzano, Alessia Cappelli, Consuelo Amantini, Guido Favia, Anna Maria Eleuteri, Mauro Angeletti
    Abstract:

    The yeast Wickerhamomyces anomalus has several applications in the food industry due to its antimicrobial potential and wide range of biotechnological properties. In particular, a specific strain of Wickerhamomyces anomalus isolated from the malaria mosquito Anopheles stephensi, namely WaF17.12, was reported to secrete a killer toxin with strong anti-plasmodial effect on different developmental stages of Plasmodium berghei; therefore, we propose its use in the symbiotic control of malaria. In this study, we focused on the identification/characterization of the protein toxin responsible for the observed antimicrobial activity of the yeast. For this purpose, the culture medium of the killer yeast strain WaF17.12 was processed by means of lateral flow filtration, anion exchange and gel filtration chromatography, immunometric methods, and eventually analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on this concerted approach, we identified a protein with a molecular weight of approximately 140 kDa and limited electrophoretic mobility, corresponding to a high molecular weight β-glucosidase, as confirmed by activity tests in the presence of specific inhibitors.

  • Isolation of a Wickerhamomyces anomalus yeast strain from the sandfly Phlebotomus perniciosus, displaying the killer phenotype
    Medical and Veterinary Entomology, 2015
    Co-Authors: Elena Martin, Irene Ricci, Laura Giovati, Gioia Bongiorno, Matteo Montagna, E.e Crotti, C.f Damiani, Luigi Gradoni, Luciano Polonelli, Guido Favia
    Abstract:

    The yeast Wickerhamomyces anomalus has been studied for its wide biotechnological potential, mainly for applications in the food industry. Different strains of W. anomalus have been isolated from diverse habitats and recently from insects, including mosquitoes of medical importance. This paper reports the isolation and phylogenetic characterization of W. anomalus from laboratory-reared adults and larvae of Phlebotomus perniciosus (Diptera: Psychodidae), a main phlebotomine vector of human and canine leishmaniasis. Of 65 yeast strains isolated from P. perniciosus, 15 strains were identified as W. anomalus; one of these was tested for the killer phenotype and demonstrated inhibitory activity against four yeast sensitive strains, as reported for mosquito-isolated strains. The association between P. perniciosus and W. anomalus deserves further investigation in order to explore the possibility that this yeast may exert inhibitory/killing activity against Leishmania spp.

  • A rapid qPCR method to investigate the circulation of the yeast Wickerhamomyces anomalus in humans.
    The new microbiologica, 2015
    Co-Authors: Sara Epis, Matteo Valzano, Guido Favia, Aida Capone, Elena Martin, Michela Paolucci, Chiara Bazzocchi, Jovana Bozic, Stefano Novati, Irene Ricci
    Abstract:

    The yeast Wickerhamomyces anomalus has been proposed for many biotechnological applications in the food industry. However, a number of opportunistic pathogenic strains have been reported as causative agents of nosocomial fungemia. Recognition of potentially pathogenic isolates is an important challenge for the future commercialization of this yeast. The isolation of W. anomalus from different matrices and, recently, from mosquitoes, requires further investigations into its circulation in humans. Here we present a qPCR protocol for the detection of W. anomalus in human blood samples and the results of a screening of 525 donors, including different classes of patients and healthy people.

  • A Wickerhamomyces anomalus Killer Strain in the Malaria Vector Anopheles stephensi
    PLoS ONE, 2014
    Co-Authors: Alessia Cappelli, Matteo Valzano, Claudia Damiani, Sara Epis, Claudio Bandi, Stefania Conti, Ulisse Ulissi, Luciano Polonelli, Maria Gabriella Gabrielli, Guido Favia
    Abstract:

    The yeast Wickerhamomyces anomalus has been investigated for several years for its wide biotechnological potential, especially for applications in the food industry. Specifically, the antimicrobial activity of this yeast, associated with the production of Killer Toxins (KTs), has attracted a great deal of attention. The strains of W. anomalus able to produce KTs, called “killer” yeasts, have been shown to be highly competitive in the environment. Different W. anomalus strains have been isolated from diverse habitats and recently even from insects. In the malaria mosquito vector Anopheles stephensi these yeasts have been detected in the midgut and gonads. Here we show that the strain of W. anomalus isolated from An. stephensi, namely WaF17.12, is a killer yeast able to produce a KT in a cell-free medium (in vitro) as well as in the mosquito body (in vivo). We showed a constant production of WaF17.12-KT over time, after stimulation of toxin secretion in yeast cultures and reintroduction of the activated cells into the mosquito through the diet. Furthermore, the antimicrobial activity of WaF17.12-KT has been demonstrated in vitro against sensitive microbes, showing that strain WaF17.12 releases a functional toxin. The mosquito-associated yeast WaF17.12 thus possesses an antimicrobial activity, which makes this yeast worthy of further investigations, in view of its potential as an agent for the symbiotic control of malaria.

Volkmar Passoth - One of the best experts on this subject based on the ideXlab platform.

  • Spruce sugars and poultry hydrolysate as growth medium in repeated fed-batch fermentation processes for production of yeast biomass
    Bioprocess and Biosystems Engineering, 2020
    Co-Authors: David Lapeña, Volkmar Passoth, Pernille M. Olsen, Magnus Ø. Arntzen, Gergely Kosa, Vincent G. H. Eijsink, Svein J. Horn
    Abstract:

    The production of microbial protein in the form of yeast grown on lignocellulosic sugars and nitrogen-rich industrial residues is an attractive approach for reducing dependency on animal and plant protein. Growth media composed of enzymatically saccharified sulfite-pulped spruce wood, enzymatic hydrolysates of poultry by-products and urea were used for the production of single-cell protein. Strains of three different yeast species, Cyberlindnera jadinii , Wickerhamomyces anomalus and Blastobotrys adeninivorans, were cultivated aerobically using repeated fed-batch fermentation up to 25 L scale. Wickerhamomyces anomalus was the most efficient yeast with yields of 0.6 g of cell dry weight and 0.3 g of protein per gram of glucose, with cell and protein productivities of 3.92 g/L/h and 1.87 g/L/h, respectively. Using the conditions developed here for producing W. anomalus , it would take 25 industrial (200 m^3) continuously operated fermenters to replace 10% of the fish feed protein used in Norway.

  • Growth performance, nutrient digestibility and intestinal morphology of rainbow trout (Oncorhynchus mykiss) fed graded levels of the yeasts Saccharomyces cerevisiae and Wickerhamomyces anomalus
    Aquaculture Nutrition, 2019
    Co-Authors: Aleksandar Vidakovic, Volkmar Passoth, Anders Kiessling, David Huyben, Henrik Sundh, Andreas Nyman, Jouni Vielma, Torbjörn Lundh
    Abstract:

    In a 10‐week study, we evaluated the effects of replacing 20%, 40% or 60% of fishmeal (present in control diet at 300 g/kg) on a digestible protein basis with yeast Saccharomyces cerevisiae or a yeast mixture of Wickerhamomyces anomalus and S. cerevisiae on growth performance, nutrient digestibility, nutrient retention and intestinal health of rainbow trout (Oncorhynchus mykiss). Triplicate tanks with 35 rainbow trout (144.7 ± 25.1 g mean ± SEM) were fed rations of 1.5% of total biomass per tank. Replacement of 60% of fishmeal with yeast mixture resulted in lower specific growth rate of 1.0% versus 1.2%/day for other diets. Apparent digestibility coefficients for crude protein and most amino acids were highest in fish fed fishmeal‐based diet, with similar values for fish fed the diet with 20% replacement with yeast mixture. Diet with 20% replacement with yeast mixture resulted in highest phosphorus digestibility. Replacement of 60% of fishmeal with S. cerevisiae resulted in oedematous mucosal fold tips in the proximal intestine. The results of this study suggest that these yeasts can replace up to 40% of fishmeal under current inclusion levels in diets for rainbow trout without compromising growth performance, nutrient digestibility or intestinal health.

  • Effects of dietary inclusion of the yeasts Saccharomyces cerevisiae and Wickerhamomyces anomalus on gut microbiota of rainbow trout
    Aquaculture, 2017
    Co-Authors: David Huyben, Volkmar Passoth, Anders Kiessling, Aleksandar Vidakovic, Andreas Nyman, Richard D. Moccia, Johan Dicksved, Torbjörn Lundh
    Abstract:

    Abstract Rainbow trout (Oncorhynchus mykiss) were fed for 10 weeks on a diet containing either 30% fish meal (FM) or with 20, 40 and 60% replacement of fish meal protein with Saccharomyces cerevisiae (SC) or a mixture of Wickerhamomyces anomalus and S. cerevisiae (WA). Luminal contents and mucosal tissue from the distal intestine were collected and analysed for yeast and bacterial loads by agar plating. Diversity and abundance were determined by sequencing of amplicons generated from the 26S rRNA (yeast) and 16S rRNA (bacteria) genes. In addition, the diets were analysed before and after feed extrusion to determine the viability and composition of the yeasts ingested by the fish. After extrusion, 9–10 log cells g− 1 of yeast were still intact in the SC and WA diets, but culturable yeast showed log-reductions of 5–7 CFU g− 1. For yeasts isolated from the gut contents, 81–96% of colonies consisted of Debaryomyces hansenii, with few or no colonies of S. cerevisiae or W. anomalus despite their high inclusion rate in the diets. Characterisation of gut bacteria using Illumina MiSeq showed that 70 and 19% of sequences were classified to the phyla Firmicutes and Proteobacteria, specifically sequences identified as Leuconostocaceae, Lactobacillaceae and Photobacterium. Compared with the FM diet, the WA40 diet reduced bacterial diversity, whereas the WA60 diet increased the abundance of the pathogenic yeast Candida albicans and reduced lactic acid bacteria in the gut. Overall, 40 and 60% replacement of fish meal protein with a mixture of W. anomalus and S. cerevisiae significantly altered the gut microbiota of rainbow trout, while 20% replacement and diets with only S. cerevisiae had little or no effect.

  • Combined moist airtight storage and feed fermentation of barley by the yeast Wickerhamomyces anomalus and a lactic acid bacteria consortium
    Frontiers in Plant Science, 2015
    Co-Authors: Jenny Borling Welin, Karin Lyberg, Volkmar Passoth, Matilda Olstorpe
    Abstract:

    This study combined moist airtight storage of moist grain with pig feed fermentation. Starter cultures with the potential to facilitate both technologies were added to airtight stored moist crimped cereal grain, and the impact on storage microflora and the quality of feed fermentations generated from the grain was investigated. Four treatments were compared: three based on moist barley, either un inoculated (M), inoculated with Wickerhamomyces anomalus (W), or inoculated with W. anomalus and LAB starter culture, containing Pediococcus acidilactici DSM 16243, Pediococcus pentosaceus DSM 12834 and Lactobacillus plantarum DSM 12837 (WLAB); and one treatment based on dried barley (D). After 6 weeks of storage, four feed fermentations FM, FW, FWLAB, and FD, were initiated from M, W, WLAB and D, respectively, by mixing the grain with water to a dry matter content of 30%. Each treatment was fermented in batch initially for 7 days and then kept in a continuous mode by adding new feed daily with 50% back-slop. During the 6 week storage period, the average water activity decreased in M, W and WLAB from 0.96 to 0.85, and cereal pH decreased from approximately 6.0 at harvest to 4.5. Feed fermentation conferred a further pH decrease to 3.8 – 4.1. In M, W and WLAB, moulds and Enterobacteriaceae were mostly below detection limit, whereas both organism groups were detected in D. In fermented feed, Enterobacteriaceae were below detection limit in almost all conditions. Moulds were detected in FD, for most of the fermentation time in FM and at some sampling points in FW and FWLAB. Starter organisms, especially W. anomalus and L. plantarum comprised a considerable proportion of the yeast and LAB populations, respectively, in both stored grain and fermented feed. However, autochthonous Pichia kudriavzevii and Kazachstania exigua partially dominated the yeast populations in stored grain and fermented feed, respectively.

  • Strain- and temperature-dependent changes of fatty acid composition in Wickerhamomyces anomalus and Blastobotrys adeninivorans.
    Biotechnology and Applied Biochemistry, 2013
    Co-Authors: Matilda Olstorpe, Jana Pickova, Anders Kiessling, Volkmar Passoth
    Abstract:

    The fatty acid (FA) profiles of two strains of the yeasts Wickerhamomyces anomalus and Blastobotrys (Arxula) adeninivorans at cultivation temperatures from 15 to 30 °C were characterized. Besides the common even-numbered C16 and C18 FAs, substantial proportions of the uneven-numbered C17:1 were found in both species. C18:3(n-3) (alpha linolenic acid) made up to 3% of the total FAs in all strains. Considerable strain differences occurred, with regard to both the presence of single FAs and parameters like the double binding index (DBI) and C16:C18 ratio. W. anomalus J121 formed C18:1(n-5) (up to 10.9% of the total FAs) but no C18:1(n-7), whereas in W. anomalus VKM160, no C18:1(n-5) was found but up to 14.6% C18:1(n-7). Similarly, B. adeninivorans CBS 8244 formed exclusively C18:1(n-7) (maximum 9%) and CBS 7377 C18:1(n-5) (maximum 12.6%). W. anomalus J121 had the lowest DBI (0.72) at 15 °C and the highest (0.92) at 20 °C, at which point the values decreased with increasing temperatures. In W. anomalus VKM160 and both B. adeninivorans strains, DBI was highest at 15 °C and decreased with increasing temperature. In J121, the C16:C18 ratio was highest at 15 °C, decreasing at higher temperatures, whereas in the other strains, the opposite trend was observed.

Disney Ribeiro Dias - One of the best experts on this subject based on the ideXlab platform.

  • Lipid production by yeasts grown on crude glycerol from biodiesel industry.
    Preparative Biochemistry & Biotechnology, 2017
    Co-Authors: Karla Silva Teixeira Souza, Rosane Freitas Schwan, Cíntia Lacerda Ramos, Disney Ribeiro Dias
    Abstract:

    The main carbon source used for growth by four yeast strains (Yarrowia lipolytica CCMA 0357, Y. lipolytica CCMA 0242, Wickerhamomyces anomalus CCMA 0358, and Cryptococcus humicola CCMA 0346) and th...

  • New glycolipid biosurfactants produced by the yeast strain Wickerhamomyces anomalus CCMA 0358.
    Colloids and Surfaces B: Biointerfaces, 2017
    Co-Authors: Karla Silva Teixeira Souza, Rosane Freitas Schwan, Disney Ribeiro Dias, Eduardo J. Gudiña, Zélia Azevedo, Victor De Freitas, Lígia R. Rodrigues, José A. Teixeira
    Abstract:

    In this work, biosurfactant production by several yeast strains was evaluated using different culture media. The best results were obtained with the strain Wickerhamomyces anomalus CCMA 0358 growing in a culture medium containing glucose (1g/L) and olive oil (20g/L) as carbon sources. This strain produced 2.6g of biosurfactant per liter after 24h of growth. The crude biosurfactant reduced the surface tension of water to values around 31mN/m, and its critical micelle concentration was 0.9mg/mL. This biosurfactant was characterized through mass spectrometry (MS), and nuclear magnetic resonance (NMR) as a mixture of two different glycolipids, comprising a sugar moiety linked to one or three molecules of oleic acid. To the best of our knowledge, these biosurfactants are structurally different from those previously reported. Furthermore, the crude biosurfactant exhibited antimicrobial activity against several microorganisms, including the pathogens Candida albicans, Escherichia coli, Staphylococcus epidermidis and Streptococcus agalactiae, which opens the possibility for its use in several biomedical applications.

  • Eco-friendly biosurfactant from Wickerhamomyces anomalus CCMA 0358 as larvicidal and antimicrobial
    Microbiological Research, 1
    Co-Authors: Natalia De Andrade Teixeira Fernandes, Angélica Cristina De Souza, Luara Aparecida Simões, Gustavo Magno Ferreira Dos Reis, Karla Silva Teixeira Souza, Rosane Freitas Schwan, Disney Ribeiro Dias
    Abstract:

    Kitchen waste oil (KWO) was evaluated as a substrate for production of biosurfactant by Wickerhamomyces anomalus CCMA 0358 and was tested against Aedes aegypti larvae, the mosquito causing neglected diseases, such as dengue fever, Zika, and Chikungunya, achieving 100 % mortality in the lowest concentration (6.25 %) evaluated in 24 h. Furthermore, possible applications of this compound were evaluated as antibacterial, antiadhesive, and antifungal. At a concentration of 50 %, the biosurfactant was found to inhibit the growth of Bacillus cereus, showing high inhibitions levels against Salmonella Enteritidis, Staphylococcus aureus, and Escherichia coli. The antifungal activity was evaluated against Aspergillus, Cercospora, Colletotrichum, and Fusarium, obtaining results of up to 95 % inhibition. In addition to these promising results, the yeast W. anomalus produced the biosurfactant from an inexpensive substrate, which increases the possibility of its application in several industries owing to the low cost involved.