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Toxins Sep 2021Possible implications and applications of the yeast killer phenomenon in the fight against infectious diseases are reviewed, with particular reference to some... (Review)
Review
Possible implications and applications of the yeast killer phenomenon in the fight against infectious diseases are reviewed, with particular reference to some wide-spectrum killer toxins (KTs) produced by and other related species. A perspective on the applications of these KTs in the medical field is provided considering (1) a direct use of killer strains, in particular in the symbiotic control of arthropod-borne diseases; (2) a direct use of KTs as experimental therapeutic agents; (3) the production, through the idiotypic network, of immunological derivatives of KTs and their use as potential anti-infective therapeutics. Studies on immunological derivatives of KTs in the context of vaccine development are also described.
Topics: Anti-Infective Agents; Communicable Diseases; Cytotoxins; Humans; Killer Factors, Yeast; Saccharomycetales; Vaccine Development
PubMed: 34564659
DOI: 10.3390/toxins13090655 -
Mycology 2021Non-conventional wine yeasts are extensively studied as promising producers of hydrolytic enzymes and as potential starter cultures in winemaking due to their ability to...
Non-conventional wine yeasts are extensively studied as promising producers of hydrolytic enzymes and as potential starter cultures in winemaking due to their ability to improve organoleptic properties of wine. Thirty-six yeast strains of enological and brewery origin from the Ukrainian Collection of Microorganisms belonging to , and genera have been screened for the production of extracellular hydrolases, stress tolerance, fermentative activity, and other traits of enological interest. This study revealed the high incidence of lipolytic, proteolytic, and β-glucosidase activities among the yeasts, while no pectinase activity was detected. Esterase, cellulase and glucanase activities were found in a small proportion of yeasts (8.33-16.66%). Several , and strains demonstrated a wide range of hydrolytic activities. High tolerance to stress factors (ethanol, osmotic, and oxidative stress) present during alcoholic fermentation was detected in and strains. Fermentative activity of several yeast strains was evaluated in microfermentations in a model semi-synthetic medium. Strain UCM Y-216 was selected as the most promising culture for winemaking due to its hydrolytic activities, tolerance to stress factors and other valuable metabolic traits. This study represents the first step for selecting a non-conventional yeast strain of enological origin as a potential co-culture for winemaking.
PubMed: 34552811
DOI: 10.1080/21501203.2020.1837272 -
Animal Bioscience Apr 2022This study aimed to determine the appropriate supplementation level of lactic acid bacteria (LAB; Lactobacillus plantarum and Bacillus clausii), yeast (Saccharomyces...
Effect of lactic acid bacteria and yeast supplementation on anti-nutritional factors and chemical composition of fermented total mixed ration containing cottonseed meal or rapeseed meal.
OBJECTIVE
This study aimed to determine the appropriate supplementation level of lactic acid bacteria (LAB; Lactobacillus plantarum and Bacillus clausii), yeast (Saccharomyces cariocanus and Wickerhamomyces anomalus) for degrading free gossypol and glucosinolate in the fermented total mixed ration (TMR) containing cottonseed meal (CSM) or rapeseed meal (RSM), to improve the utilization efficiency of these protein sources.
METHODS
For LAB, L. plantarum or B. clausii was inoculated at 1.0×108, 1.0×109, 1.0×1010, and 1.0×1011 colony-forming unit (CFU)/kg dry matter (DM), respectively. For yeast, S. cariocanus or W. anomalus was inoculated at 5×106, 5×107, 5×108, and 5×109 CFU/kg DM, respectively. The TMR had 50% moisture and was incubated at 30°C for 48 h. After fermentation, the chemical compositions, and the contents of free gossypol and glucosinolate were determined.
RESULTS
The results showed that the concentration of free gossypol content was reduced (p<0.05), while that of the crude protein content was increased (p<0.05) in the TMR containing CSM inoculated by B. clausii (1×109 CFU/kg DM) or S. cariocanus (5×109 CFU/kg DM). Similarly, the content of glucosinolate was lowered (p<0.05) and the crude protein content was increased (p<0.05) in TMR containing RSM inoculated with B. clausii (1×1010 CFU/kg DM) or S. cariocanus (5×109 CFU/g DM).
CONCLUSION
This study confirmed that inclusion of B. clausii with 1.0×109 or 1.0×1010 CFU/kg DM, or S. cariocanus (5×109 CFU/kg DM) to TMR containing CSM/RSM improved the nutritional value and decreased the contents of anti-nutritional factors.
PubMed: 34530504
DOI: 10.5713/ab.21.0270 -
Frontiers in Microbiology 2021To study the mechanism by which induced with chitosan (1% w/v) controls blue mold disease in table grapes caused by , this study evaluated alterations in three yeast...
To study the mechanism by which induced with chitosan (1% w/v) controls blue mold disease in table grapes caused by , this study evaluated alterations in three yeast enzymatic activities. The changes in the five primary disease defense-related enzymes and two non-enzyme activities of table grapes were assayed. The results of the study showed that chitosan (1% w/v) significantly increased the yeast β-1,3-glucanase, catalase (CAT), and malondialdehyde (MDA) activities. Furthermore, alone or induced with chitosan (1% w/v) significantly increased the table grapes enzymatic activities of Polyphenol oxidase (PPO), phenylalanine (PAL), peroxidase (POD), and catalase (CAT) compared to the control. The RT-qPCR results also confirmed that the genes of these major disease defense enzymes were up-regulated when the table grapes were treated with . The highest results were recorded when the fruit was treated by yeast induced with chitosan (1% w/v). The phenolic compounds, in addition to their nutritional value, can also increase the antimicrobial properties of table grapes. The current experiment determined that the total phenol and flavonoid contents of table grapes showed the highest results for fruits treated by induced with chitosan compared with the control. Generally, the increment of these fruit enzymatic and non-enzymatic activities shows improved table grape defense against the pathogenic fungus. The induction of the yeast with chitosan also increases its bio-control efficacy against the pathogen. This study will enable future detailed investigation in the yeast pathogen control mechanisms and the use of yeasts as bio-pesticides.
PubMed: 34367105
DOI: 10.3389/fmicb.2021.704519 -
Foods (Basel, Switzerland) Jul 2021Phenolic compounds are natural substances that can be obtained from plants. Many of them are potent growth inhibitors of foodborne pathogenic microorganisms, however,...
Phenolic compounds are natural substances that can be obtained from plants. Many of them are potent growth inhibitors of foodborne pathogenic microorganisms, however, phenolic activities against spoilage yeasts are rarely studied. In this study, planktonic and biofilm growth, and the adhesion capacity of , , and spoilage yeasts were investigated in the presence of hydroxybenzoic acid, hydroxycinnamic acid, stilbene, flavonoid and phenolic aldehyde compounds. The results showed significant anti-yeast properties for many phenolics. Among the tested molecules, cinnamic acid and vanillin exhibited the highest antimicrobial activity with minimum inhibitory concentration (MIC) values from 500 µg/mL to 2 mg/mL. Quercetin, (-)-epicatechin, resveratrol, 4-hydroxybenzaldehyde, -coumaric acid and ferulic acid were also efficient growth inhibitors for certain yeasts with a MIC of 2 mg/mL. The , and biofilms were the most sensitive to the phenolics, while the biofilm was quite resistant against the activity of the compounds. Fluorescence microscopy revealed disrupted biofilm matrix on glass surfaces in the presence of certain phenolics. Highest antiadhesion activity was registered for cinnamic acid with inhibition effects between 48% and 91%. The active phenolics can be natural interventions against food-contaminating yeasts in future preservative developments.
PubMed: 34359522
DOI: 10.3390/foods10071652 -
Journal of Infection in Developing... Jun 2021Fungemia in preterm infants results in high mortality and morbidity. The genotypes, drug susceptibilities of Candida pelliculosa strains, and clinical features of two...
INTRODUCTION
Fungemia in preterm infants results in high mortality and morbidity. The genotypes, drug susceptibilities of Candida pelliculosa strains, and clinical features of two outbreaks of neonatal candidemia caused by C. pelliculosa were analyzed, in order to provide evidence for the outbreaks and characteristics of C. pelliculosa neonatal candidemia.
METHODOLOGY
The strains were genotyped by pulsed-field gel electrophoresis to investigate their genetic relatedness. The broth microdilution method was used to determine in vitro susceptibility of the isolates to antifungal drugs. Clinical features of the infected patients were collected to analyze the risks for C. pelliculosa infection.
RESULTS
Fourteen neonates, hospitalized in the neonatal intensive care unit from November 2012 to October 2013, were infected by C. pelliculosa. All 14 patients were cured after treatment with fluconazole and discharged without any complications. The C. pelliculosa isolates from the 14 patients were clustered into two groups, indicating that the outbreaks were caused by two types of strains. Eight of nine strains isolated from the 2013 outbreak were clustered into the same group, while one isolate was grouped together with five isolates from the 2012 outbreak. In vitro experiments demonstrated high antifungal activity of fluconazole, voriconazole, amphotericin B, and 5-fluorocytosine to C. pelliculosa. The common symptoms of C. pelliculosa candidaemia were fever, cyanosis, polypnea, hypoactivity, and apnea.
CONCLUSIONS
The current study revealed high in vitro susceptibility of C. pelliculosa to antifungals. As C. pelliculosa candidaemia cannot be characterized by clinical symptoms and routine blood testing alone, monitoring unusual strains isolated from immunodeficient hosts is very important to prevent possible outbreaks.
Topics: Antifungal Agents; Candidemia; China; Clone Cells; Disease Outbreaks; Female; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Intensive Care Units, Neonatal; Male; Microbial Sensitivity Tests; Saccharomycetales
PubMed: 34242199
DOI: 10.3855/jidc.12103 -
Foods (Basel, Switzerland) Jun 2021Transcriptome analysis (TA) was conducted to characterize the transcriptome changes in postharvest disease-related genes of table grapes following treatment with...
Transcriptome analysis (TA) was conducted to characterize the transcriptome changes in postharvest disease-related genes of table grapes following treatment with induced with chitosan (1% /). In the current study, the difference in the gene expression of table grapes after treatment with induced with chitosan and that of a control group was compared 72 h post-inoculation. The study revealed that postharvest treatment of table grapes with induced with chitosan could up-regulate genes that have a pivotal role in the fruit's disease defense. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) results also confirmed that GO terms and the KEGG pathways, which have pivotal roles in plant disease resistance, were significantly enriched. The up-regulated genes of the treatment group have a unique function in the fruit's disease resistance compared to the control group. Generally, most genes in the plant-pathogen interaction pathway; the plant Mitogen-activated protein kinase (MAPK) signaling pathway; the plant hormone signal transduction pathway; the pathway of glutathione metabolism; the pathway of phenylalanine, tyrosine, and tryptophan biosynthesis; and the pathway of flavonoid biosynthesis were all up-regulated. These up-regulations help the fruit to synthesize disease-resistant substances, regulate the reactive oxygen species (ROS), enhance the fruit cell wall, and enrich hormone signal transduction during the pathogen's attack. This study is useful to overcome the lags in applying transcriptomics technology in postharvest pathology, and will provide insight towards developing other alternative methods to using bio-pesticides to control postharvest diseases of perishables.
PubMed: 34206622
DOI: 10.3390/foods10071451 -
BMC Infectious Diseases Jun 2021Candida pelliculosa is an ecological fungal species that can cause infections in immunocompromised individuals. Numerous studies globally have shown that C. pelliculosa...
BACKGROUND
Candida pelliculosa is an ecological fungal species that can cause infections in immunocompromised individuals. Numerous studies globally have shown that C. pelliculosa infects neonates. An outbreak recently occurred in our neonatal intensive care unit; therefore, we aimed to evaluate the risk factors in this hospital-acquired fungal infection.
METHODS
We performed a case-control study, analysing the potential risk factors for neonatal infections of C. pelliculosa so that infection prevention and control could be implemented in our units. Isolated strains were tested for drug resistance and biofilm formation, important factors for fungal transmission that give rise to hospital-acquired infections.
RESULTS
The use of three or more broad-spectrum antimicrobials or long hospital stays were associated with higher likelihoods of infection with C. pelliculosa. The fungus was not identified on the hands of healthcare workers or in the environment. All fungal isolates were susceptible to anti-fungal medications, and after anti-fungal treatment, all infected patients recovered. Strict infection prevention and control procedures efficiently suppressed infection transmission. Intact adhesin-encoding genes, shown by genome analysis, indicated possible routes for fungal transmission.
CONCLUSIONS
The use of three or more broad-spectrum antimicrobials or a lengthy hospital stay is theoretically associated with the risk of infection with C. pelliculosa. Strains that we isolated are susceptible to anti-fungal medications, and these were eliminated by treating all patients with an antifungal. Transmission is likely via adhesion to the cell surface and biofilm formation.
Topics: Antifungal Agents; Biofilms; Candidiasis; Case-Control Studies; China; Cross Infection; Disease Outbreaks; Equipment and Supplies; Female; Health Personnel; Humans; Infant, Newborn; Infection Control; Intensive Care Units, Neonatal; Length of Stay; Male; Microbial Sensitivity Tests; RNA, Fungal; Risk Factors; Saccharomycetales
PubMed: 34187390
DOI: 10.1186/s12879-021-06295-1 -
Animals : An Open Access Journal From... Apr 2021This study isolates and identifies () AR, and studies its effect on the growth and health of weaned pigs. A strain from solid wine koji is isolated and identified...
This study isolates and identifies () AR, and studies its effect on the growth and health of weaned pigs. A strain from solid wine koji is isolated and identified using 26S rDNA analysis, and its culture conditions are optimized. Heat tolerance, bile salt tolerance, artificial gastric, and intestinal juice tolerance are evaluated. In our methodology, thirty 28 d Large White × Landrace × Rongchang weaned pigs were randomly divided into three groups with 10 barrows in each, and fed a maize-soybean meal diet and orally administered 0.85% saline (CK), 1 mL 1 × 10 cfu/mL (), and 1 mL 1 × 10 cfu/mL once daily for 28 days. A strain was identified and named AR. AR grew best in yeast extract peptone dextrose medium with pH 5.0 at 28 °C, 180 r/min and could tolerate 45 °C for 0.5 h, 0.2% pig bile salts, simulated gastric fluid, and 1.0% simulated intestinal fluid. Our results show that compared with the CK group, orally administered AR increases average daily gain, the ileal villus height, the ileal mucosal concentrations of occludin and zonula occluens-1, the serum glucose and total protein concentration, total superoxide dismutase, glutathione peroxidase, and total antioxidative capacity activity, the trypsin and lipase activity in jejunal and ileal contents, the jejunal and ileal mucosa mRNA levels of ALP, TNF-α, and TLR-2, and the relative abundance of Bacteroidetes, Actinobacteria, Succinivibrionaceae, Lachnospiraceae, and Prevotellaceae ( < 0.05). Compared with the CK group, oral administration of AR decreased the incidence of diarrhea, aspartate aminotransferase activity, alanine amino-transferase-activity, malondialdehyde, D-lactic acid and endotoxin content in serum, the mRNA level of aminopeptidase N of ileum mucosa, and the relative abundance of Proteobacteria, Clostridiaceae, Campylobacteraceae, Vibrionaceae, , and Pseudon ( < 0.05). Collectively, the study indicates that AR can tolerate high acidity and high bile salts, and has high survivability in the artificial gastric intestinal juice environment. Oral administration of AR improves the growth performance, reduces the incidence of diarrhea, enhances intestinal barrier function, and improves microflora in weaned pigs.
PubMed: 33924225
DOI: 10.3390/ani11041179 -
Infectious Disease Reports Apr 2021Fungal skin infections and iatrogenic disease of companion animals continue to be an ongoing issue for veterinarians, where misdiagnosis or inapt medical treatment...
Fungal skin infections and iatrogenic disease of companion animals continue to be an ongoing issue for veterinarians, where misdiagnosis or inapt medical treatment result in secondary conditions within animals. The widespread use of antifungals in both modern medicine and agriculture has resulted in concomitant resistance in species, where zoonotic transfer poses a risk to public health. Studies described herein assess the resistance of pathogenic species isolated from companion animals to a battery of conventional antimicrobial agents. Levels of resistance were detected using recognised in vitro methods, where additional novel therapeutic and biocide options were also extensively investigated. Results show high levels of resistance to the three main families of antifungal agents, namely caspofungin, Amp B and fluconazole. Resistance in , , and species is described herein, highlighting the need for defined species-specific antifungal breakpoints, and for and species which also have zoonotic potential. Novel compound phendione showed promising antimicrobial activity, with MICs determined for both fungal and bacterial species. The biocidal options investigated also showed potential to act as intermediate-level disinfectants, where peracetic acid proved most effective against fungal spore formers.
PubMed: 33920450
DOI: 10.3390/idr13020034