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Molecules (Basel, Switzerland) Jan 2023Olive mill wastewater (OMWW) represents a by-product but also a source of biologically active compounds, and their recycling is a relevant strategy to recover income and...
Olive mill wastewater (OMWW) represents a by-product but also a source of biologically active compounds, and their recycling is a relevant strategy to recover income and to reduce environmental impact. The objective of the present study was to obtain a new functional beverage with a health-promoting effect starting from OMWW. Fresh OMWW were pre-treated through filtration and/or microfiltration and subjected to fermentation using strains belonging to , and . During fermentation, phenolic content and hydroxytyrosol were monitored. Moreover, the biological assay of microfiltered fermented OMWW was detected versus tumor cell lines and as anti-inflammatory activity. The results showed that in microfiltered OMWW, fermentation was successfully conducted, with the lowest pH values reached after 21 days. In addition, in all fermented samples, an increase in phenol and organic acid contents was detected. Particularly, in samples fermented with and in single and combined cultures, the concentration of hydroxytyrosol reached values of 925.6, 902.5 and 903.5 mg/L, respectively. Moreover, biological assays highlighted that fermentation determines an increase in the antioxidant and anti-inflammatory activity of OMWW. Lastly, an increment in the active permeability on Caco-2 cell line was also revealed. In conclusion, results of the present study confirmed that the process applied here represents an effective strategy to achieve a new functional beverage.
Topics: Humans; Wastewater; Olea; Caco-2 Cells; Phenols; Environment; Industrial Waste; Olive Oil
PubMed: 36677704
DOI: 10.3390/molecules28020646 -
Molecular Plant-microbe Interactions :... Apr 2007The modes of action of the antagonistic yeast Pichia anomala (strain K) have been studied; however, thus far, there has been no clear demonstration of the involvement of...
The modes of action of the antagonistic yeast Pichia anomala (strain K) have been studied; however, thus far, there has been no clear demonstration of the involvement of exo-beta-1,3-glucanase in determining the level of protection against Botrytis cinerea afforded by this biocontrol agent on apple. In the present study, the exo-beta-1,3-glucanase-encoding genes PAEXG1 and PAEXG2, previously sequenced from the strain K genome, were separately and sequentially disrupted. Transfer of the URA3-Blaster technique to strain K, allowing multiple use of URA3 marker gene, first was validated by efficient inactivation of the PaTRP1 gene and recovery of a double auxotrophic strain (uracil and tryptophan). The PAEXG1 and PAEXG2 genes then were inactivated separately and sequentially with the unique URA3 marker gene. The resulting mutant strains showed a significantly reduced efficiency of biocontrol of B. cinerea when applied to wounded apple fruit, the calculated protection level dropping from 71% (parental strain) to 8% (mutated strain) under some experimental conditions. This suggests that exo-beta-1,3-glucanases play a role in the biological control of B. cinerea on apple. Furthermore, biological control experiments carried out in this study underline the complexity of the host-antagonist-pathogen interaction. Two experimental parameters (yeast inoculum concentration and physiological stage of the fruit) were found to influence dramatically the protection level. Results also suggest that, under some conditions, the contribution of exo-beta-1,3-glucanase to biological control may be masked by other modes of action, such as competition.
Topics: Botrytis; Food Microbiology; Gene Silencing; Genes, Fungal; Glucan 1,3-beta-Glucosidase; Malus; Mutagenesis; Pest Control, Biological; Pichia; Plant Diseases
PubMed: 17427807
DOI: 10.1094/MPMI-20-4-0371 -
Microbial Cell Factories Aug 2015Sugar alcohols have been widely applied in the fields of food and medicine owing to their unique properties. Compared to chemical production, microbial production of...
BACKGROUND
Sugar alcohols have been widely applied in the fields of food and medicine owing to their unique properties. Compared to chemical production, microbial production of sugar alcohols has become attractive because of its environmentally friendly and sustainable characteristics. Our previous study identified the nonconventional yeast Pichia anomala TIB-x229 as a potential producer of sugar alcohols from glucose. To further improve strain performance, we combined genome shuffling with optimized high throughput screening methods for the directed improvement of nonconventional yeast and complex phenotypes.
RESULTS
To accelerate strain improvement, a practical genome shuffling procedure was developed and successfully applied in the nonconventional yeast P. anomala to increase sugar alcohol production. Through two rounds of genome shuffling, an improved P. anomala isolate GS2-3 could produce 47.1 g/L total sugar alcohols from 100 g/L glucose, which was 32.3% higher than the original strain. In this process, a simple and accurate colorimetric assay was optimized and used for high throughput screening of sugar alcohol-producing strains. Moreover, a fluorescence-activated cell sorting method was developed to efficiently screen protoplast fusions for genome shuffling of nonconventional yeast.
CONCLUSION
An efficient genome shuffling procedure was developed and applied to enhance the sugar alcohol production of the nonconventional yeast P. anomala. Our results provide a general platform for strain improvement of polyol-producing microorganisms or nonconventional microorganisms in the future.
Topics: DNA Shuffling; Genome, Fungal; Glucose; Pichia; Sugar Alcohols
PubMed: 26246027
DOI: 10.1186/s12934-015-0303-8 -
Frontiers in Microbiology 2023Our recent research study focused on Miang fermentation revealed that tannin-tolerant yeasts and bacteria play vital roles in the Miang production process. A high...
Our recent research study focused on Miang fermentation revealed that tannin-tolerant yeasts and bacteria play vital roles in the Miang production process. A high proportion of yeast species are associated with plants, insects, or both, and nectar is one of the unexplored sources of yeast biodiversity. Therefore, this study aimed to isolate and identify yeasts of tea flowers of var. and to investigate their tannin tolerance, which is a property essential to Miang production processes. A total of 82 yeasts were recovered from a total of 53 flower samples in Northern Thailand. It was found that two and eight yeast strains were distinct from all other known species within the genera and , respectively. These yeast strains were described as three new species, namely, , , and . The identification of these species was based on phenotypic (morphological, biochemical, and physiological characteristics) and phylogenetic analyses of a combination of the internal transcribed spacer (ITS) regions and the D1/D2 domains of the large subunit (LSU) ribosomal RNA gene. The yeast diversity in tea flowers acquired from Chiang Mai, Lampang, and Nan provinces had a positive correlation with those acquired from Phayao, Chiang Rai, and Phrae, respectively. , , and were the species uniquely found in tea flowers collected from Nan and Phrae, Chiang Mai, and Lampang provinces, respectively. Some of the tannin-tolerant and/or tannase-producing yeasts were associated with yeasts in the commercial Miang process and those found during Miang production, i.e., , , , , , , , and . In conclusion, these studies suggest that floral nectar could support the formation of yeast communities that are beneficial for Miang production.
PubMed: 36876082
DOI: 10.3389/fmicb.2023.1043430 -
Tropical Biomedicine Aug 2011The biodiversity and the killer activity of yeasts isolated from various types of fermented food in Malaysia were investigated in this study. Of 252 yeasts isolated from...
The biodiversity and the killer activity of yeasts isolated from various types of fermented food in Malaysia were investigated in this study. Of 252 yeasts isolated from 48 fermented food samples in this study, 19 yeast species were identified based on sequence analysis of the ITS1-5.8S-ITS2 partial fragments of the yeasts. A total of 29 (11.5%) of the yeast isolates demonstrated killer activity to at least one Candida species tested in this study; including 22 isolates of Trichosporon asahii, 4 isolates of Pichia anomala, and one isolate each of Pichia norvegensis, Pichia fermentans and Issatchenkia orientalis, respectively. The presence of killer yeasts reflects antagonism that occurs during microbial interaction in the fermented food, whereby certain yeasts produce killer toxins and possibly other toxic substances in competition for limited nutrients and space. The anti-Candida activity demonstrated by killer yeasts in this study should be further explored for development of alternative therapy against candidiasis.
Topics: Antibiosis; DNA, Fungal; DNA, Ribosomal; DNA, Ribosomal Spacer; Food Microbiology; Genes, rRNA; Malaysia; RNA, Fungal; RNA, Ribosomal, 5.8S; Sequence Analysis, DNA; Yeasts
PubMed: 22041766
DOI: No ID Found -
FEMS Immunology and Medical Microbiology Sep 1998Despite the development of drugs in the prophylaxis of pneumocystosis, Pneumocystis carinii remains a major opportunistic microorganism in immunosuppressed individuals,... (Review)
Review
Despite the development of drugs in the prophylaxis of pneumocystosis, Pneumocystis carinii remains a major opportunistic microorganism in immunosuppressed individuals, especially in human immunodeficiency virus-infected patients. Since side effects were frequently observed after administration of trimethoprim-sulfamethoxazole or pentamidine, the drugs which are mainly used in treating human P. carinii pneumonia (PCP), new therapeutic strategies should be developed. Over the last years, the inhibitory effect of a Pichia anomala killer toxin (PaKT), a molecule with a wide spectrum of antimicrobial activity, was characterized on P. carinii. The susceptibility of mouse and rat-derived Pneumocystis to PaKT has been demonstrated by in vitro attachment tests and in vivo infectivity assays. Nevertheless, PaKT is strongly antigenic, toxic and could not be used directly as a therapeutic agent. Then, a new strategy using killer toxin-like anti-idiotypic antibodies (KT-antiIds) mimicking the fungal toxin activity has been developed. Different KT-antiIds were obtained by idiotypic immunization with a monoclonal antibody (mabKT4). This mabKT4 neutralized the killer properties of the PaKT. KT-antiIds were produced by immunization against the variable domain (idiotype) of mAbKT4 (internal image of the killer toxin receptor), or they were obtained directly from vaginal fluid of patients affected by recurrent vaginal candidiosis. In this last case, such natural KT-antiIds were immunopurified by affinity-chromatography with mAbKT4 and their anti-P. carinii activity was then evaluated. Our results showed that both the in vitro attachment of rat-derived parasites and their infectivity to nude rats were inhibited by the KT-antiIds. With regard to KT-antiIds obtained by immunization, the antimicrobial activity of a monoclonal KT-antiIds (mAbK10) has been evaluated by using a PCP experimental nude rat model treated by mAbK10 administered by aerosol. The pneumocystosis extension was significantly reduced in this model. The monoclonal KT-antiIds were effective against P. carinii in reducing parasite proliferation in lungs of nude rats. Further experiments are in progress to study the in vivo anti-P. carinii activity of KT-antiIds by using recombinant single-chain of the variable fragment of KT-antiIds. Yeast killer toxin-like recombinant molecules could provide the basis for a new therapeutic strategy towards the control of pneumocystosis.
Topics: Animals; Antibodies, Anti-Idiotypic; Antibodies, Fungal; Humans; Killer Factors, Yeast; Mycotoxins; Pichia; Pneumocystis; Pneumonia, Pneumocystis; Recombinant Proteins
PubMed: 9792073
DOI: 10.1111/j.1574-695X.1998.tb01199.x -
Journal of Dairy Science Feb 2017The objective of this study was to identify species of yeasts in samples of high moisture corn (HMC) and corn silage (CS) collected from farms throughout the United...
The objective of this study was to identify species of yeasts in samples of high moisture corn (HMC) and corn silage (CS) collected from farms throughout the United States. Samples were plated and colonies were isolated for identification using DNA analysis. Randomly selected colonies were also identified by fatty acid methyl esters (FAME) and by physiological substrate profiling (ID 32C). For CS, Candida ethanolica, Saccharomyces bulderi, Pichia anomala, Kazachstania unispora, and Saccharomyces cerevisiae were the predominant yeasts. Pichia anomala, Issatchenkia orientalis, S. cerevisiae, and Pichia fermentans were the prevalent species in HMC. The 3 identification methods were in agreement at the species level for 16.6% of the isolates and showed no agreement for 25.7%. Agreement in species identification between ID 32C and DNA analysis, FAME and ID 32C, and FAME and DNA analysis was 41.1, 14.4, and 2.2%, respectively. Pichia anomala and I. orientalis were able to grow on lactic acid, whereas S. cerevisiae metabolized sugars (galactose, sucrose, and glucose) but failed to use lactic acid. The yeast diversity in CS and HMC varied due to type of feed and location. Differences in species assignments were seen among methods, but identification using substrate profiling generally corresponded with that based on DNA analysis. These findings provide information about the species that may be expected in silages, and this knowledge may lead to interventions that control unwanted yeasts.
Topics: Animals; Fermentation; Saccharomyces cerevisiae; Saccharomycetales; Silage; United States; Yeasts; Zea mays
PubMed: 27889126
DOI: 10.3168/jds.2016-11450 -
BMC Infectious Diseases Feb 2015Genetic variation in the ribosomal DNA (rDNA) internal transcribed spacer (ITS) region has been studied among fungi. However, the numbers of ITS sequence polymorphisms...
BACKGROUND
Genetic variation in the ribosomal DNA (rDNA) internal transcribed spacer (ITS) region has been studied among fungi. However, the numbers of ITS sequence polymorphisms in the various Candida species and their associations with sources of invasive fungal infections remain poorly investigated. Here, we characterized the intraspecific and interspecific ITS diversity of Candida spp. strains collected from patients with bloodstream or oroesophageal candidiasis.
METHODS
We selected cultures of representative medically important species of Candida as well as some rare and emerging pathogens. Identification was performed by micromorphology and by biochemical testing using an ID32C system, as well as by the sequencing of rDNA ITS. The presence of intraspecific ITS polymorphisms was characterized based on haplotype networks, and interspecific diversity was characterized based on Bayesian phylogenetic analysis.
RESULTS
Among 300 Candida strains, we identified 76 C. albicans, 14 C. dubliniensis, 40 C. tropicalis, 47 C. glabrata, 34 C. parapsilosis (sensu stricto), 31 C. orthopsilosis, 3 C. metapsilosis, 21 Meyerozyma guilliermondii (C. guilliermondii), 12 Pichia kudriavzevii (C. krusei), 6 Clavispora lusitaniae (C. lusitaniae), 3 C. intermedia, 6 Wickerhamomyces anomalus (C. pelliculosa), and 2 C. haemulonii strains, and 1 C. duobushaemulonii, 1 Kluyveromyces marxianus (C. kefyr), 1 Meyerozyma caribbica (C. fermentati), 1 Pichia norvegensis (C. norvegensis), and 1 Lodderomyces elongisporus strain. Out of a total of seven isolates with inconsistent ID32C profiles, ITS sequencing identified one C. lusitaniae strain, three C. intermedia strains, two C. haemulonii strains and one C. duobushaemulonii strain. Analysis of ITS variability revealed a greater number of haplotypes among C. albicans, C. tropicalis, C. glabrata and C. lusitaniae, which are predominantly related to endogenous sources of acquisition. Bayesian analysis confirmed the major phylogenetic relationships among the isolates and the molecular identification of the different Candida spp.
CONCLUSIONS
Molecular studies based on ITS sequencing are necessary to identify closely related and emerging species. Polymorphism analysis of the ITS rDNA region demonstrated its utility as a genetic marker for species identification and phylogenetic relationships as well as for drawing inferences concerning the natural history of hematogenous infections caused by medically important and emerging Candida species.
Topics: Candida; Candidiasis, Invasive; Communicable Diseases, Emerging; Cross Infection; DNA Mutational Analysis; DNA, Ribosomal Spacer; Genetic Variation; Humans; Phylogeny; Polymorphism, Genetic
PubMed: 25887032
DOI: 10.1186/s12879-015-0793-3 -
Genes Dec 2022Ethyl acetate is an important flavor element that is a vital component of . To date, the transcription factors that can help identify the molecular mechanisms involved...
Ethyl acetate is an important flavor element that is a vital component of . To date, the transcription factors that can help identify the molecular mechanisms involved in the synthesis of ethyl acetate have not been studied. In the present study, we sequenced and assembled the strain YF1503 transcriptomes to identify transcription factors. We identified 307 transcription factors in YF1503 using high-throughput RNA sequencing. Some transcription factors, such as C2H2, bHLH, MYB, and bZIP, were up-regulated, and these might play a role in ethyl acetate synthesis. According to the trend of ethyl acetate content, heat map results and STEM, twelve genes were selected for verification of expression levels using quantitative real-time PCR. This dynamic transcriptome analysis presents fundamental information on the transcription factors and pathways that are involved in the synthesis of ethyl acetate in aroma-producing yeast. Of significant interest is the discovery of the roles of various transcription factor genes in the synthesis of ethyl acetate.
Topics: Transcription Factors; Odorants; Yeasts; Gene Expression Profiling
PubMed: 36553608
DOI: 10.3390/genes13122341 -
Mikrobiyoloji Bulteni Oct 2021Fungal peritonitis is less commonly seen than bacterial peritonitis in patients undergoing peritoneal dialysis (PD), but it is a serious complication with high morbidity...
Fungal peritonitis is less commonly seen than bacterial peritonitis in patients undergoing peritoneal dialysis (PD), but it is a serious complication with high morbidity and mortality. It often results in catheter loss and modifying therapy from PD to hemodialysis. The causative organisms are often Candida species. In this report, a PD-associated peritonitis caused by Wickerhamomyces anomalus (Candida pelliculosa), a rare fungal infection agent with increasing clinical importance by causing different clinical pictures was presented. An outpatient peritoneal fluid culture was sent from a 48-yearold male patient, who had been undergoing continuous peritoneal dialysis (CAPD) for 9 years, due to abdominal pain and blur in peritoneal fluid during dialysis. The patient admitted to the emergency department four days later due to the persistence of his complaints. A sample of peritoneal fluid was taken in the emergency department and sent to the laboratory for microbiological analysis. In the direct microscopical examination of the peritoneal fluid; cell number was determined as 210/mm3, and no microorganisms were seen in the Gram and methylene blue staining. The patient was admitted to the nephrology service with a pre-diagnosis of PD-associated peritonitis. Enterobacter aerogenes was grown in the peritoneal fluid culture which was sent from the dialysis outpatient clinic four days ago. The peritoneal fluid sample sent from the emergency department was inoculated on 5% sheep blood , EMB and chocolate agars and no growth was detected. As the patient's complaints and peritoneal fluid leukocyte count continued to increase, peritoneal fluid cultures were repeated and recurrent growth of yeast was detected in cultures. The yeast was identified as Candida pelliculosa by matrix assisted laser desorption ionization time-of-flight mass spectrofotometry (MALDI-TOF) VITEK®MS (bioMerieux, France). The species identification was confirmed by sequencing the target ITS gene regions on the rRNA and the isolate was identified as 100% Wickerhamomyces anomalus (sexual reproduction form of Candida pelliculosa, teleomorph). The reference microdilution method was performed according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) in order to test the antifungal susceptibility. After 24 hour incubation, the minimal inhibitory concentrations (MIC) were determined as 0.03 μg/ml for amphotericin B, 0.125 μg/ml for caspofungin 0.125 μg/ml for voriconazole, 0.03 μg/ ml for itraconazole and 4 μg/ml for fluconazole. Fluconazole and anidulafungin were started for the treatment of fungal peritonitis. The patient's peritoneal dialysis catheter was removed and hemodialysis was applied to the patient. Clinical and laboratory symptoms regressed with antifungal therapy and the patient's anidulafungin treatment was discontinued for 14 days after the catheter removal. In conclusion, in patients undergoing CAPD, as in our case, fungal pathogens should also be considered although it is rare, when there is no laboratory and clinical improvement, and the response to treatment is not complete in PD-associated peritonitis to prevent delays in diagnosis and treatment.
Topics: Animals; Antifungal Agents; Candida; Humans; Male; Peritoneal Dialysis; Peritonitis; Saccharomycetales; Sheep
PubMed: 34666666
DOI: 10.5578/mb.20219718