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Foods (Basel, Switzerland) Nov 2022The co-fermentation of Saccharomyces cerevisiae and ester-producing yeasts is considered to be an effective way to improve the flavor and quality of fruit wine. In this...
The co-fermentation of Saccharomyces cerevisiae and ester-producing yeasts is considered to be an effective way to improve the flavor and quality of fruit wine. In this study, three kinds of ester-producing yeasts (Candida glabrata NCUF308.1, Pichia anomala NCUF306.1, and Wickerhamomyces anomalus NCUF307.1) and S. cerevisiae NCUF309.2 were used to simulate blueberry wine co-fermentation at different ratios. The results showed that, compared with S. cerevisiae NCUF309.2 fermentation (S), the population of S. cerevisiae NCUF309.2 in co-fermentation samples decreased to varying degrees, and the content of ethanol also decreased. The results also showed that the co-fermentation of C. glabrata NCUF308.1 and S. cerevisiae NCUF309.2 at the ratio of 1:1 (CS1), co-fermentation of P. anomala NCUF306.1 and S. cerevisiae NCUF309.2 at the ratio of 5:1 (PS5), and co-fermentation of W. anomalus NCUF307.1 and S. cerevisiae NCUF309.2 at the ratio of 5:1 (WS5) could significantly increase the content of ester compounds (p < 0.05), which was 3.29, 4.75, and 3.04 times that of the S sample, respectively. Among them, the sample of CS1 was characterized by phenethyl acetate and isoamyl acetate, while the samples of CS5 and PS5 were characterized by propyl octanoate and ethyl decanoate, and the sample of WS5 was characterized by 3-methylbutyl hexanoate. However, the contents of odor active compounds were higher in the CS1 sample. Therefore, the samples of CS1 had the potential to create the distinctive flavor of blueberry wine.
PubMed: 36429247
DOI: 10.3390/foods11223655 -
Journal of Applied Microbiology Aug 2021To determine the technological and enzymatic characteristics of 54 yeast strains belonging to 16 species previously isolated from natural fermentation media of Gemlik...
AIM
To determine the technological and enzymatic characteristics of 54 yeast strains belonging to 16 species previously isolated from natural fermentation media of Gemlik olives. The distinguishing feature of these strains, according to their selective technological and enzymatic properties using principal component analysis (PCA), was also intended.
METHODS AND RESULTS
The technological properties of yeast strains, growth characteristics at different temperatures, pH and salt concentrations were examined. Besides, yeast strains' abilities to use oleuropein as a sole carbon source, to assimilate citric acid and to produce H S were examined and their catalase, pectolytic, proteolytic and killer activities were also tested. All strains could grow between 15 and 28°C which are favourable temperatures for natural olive fermentation and they were able to tolerate high salt concentration and low pH in the brine of natural fermentation media. As a result of enzymatic characterization with API-ZYM test system, all strains have esterase activity, which is an important feature for developing table olive aroma. In this research, β-glucosidase activity, which contributes to removing bitterness out of olives, was one of the main distinguishing features of yeast strains. Several strains of Candida hellenica, Pichia anomala and Candida pelliculosa species had β-glucosidase activity. PCA tested yeasts and several strains belonging to C. hellenica (AF84-1), P. anomala (BF1-1, BF46-2) and C. pelliculosa (BF46-3, BF143-2) species have promising technological and enzymatic properties for natural table olive production.
CONCLUSION
Five promising strains belonging to C. hellenica, P. anomala and C. pelliculosa species may be suitable adjunct starter cultures with lactic acid bacteria in natural fermentation media of table olive.
SIGNIFICANCE AND IMPACT OF THE STUDY
This study has been the first contribution to the enzymatic and technological characterization of yeasts isolated from Gemlik olives in Turkey. Some strains could be proposed as a promising adjunct culture in the production of table olives.
Topics: Fermentation; Food Microbiology; Olea; Saccharomycetales; Turkey; Yeasts
PubMed: 33346384
DOI: 10.1111/jam.14979 -
Foods (Basel, Switzerland) Nov 2022Ethanol stress to yeast is well recognized and exists widely during the brewing process of alcohol products. is an important ester-producing yeast in the brewing...
Ethanol stress to yeast is well recognized and exists widely during the brewing process of alcohol products. is an important ester-producing yeast in the brewing process of Chinese and other alcohol products. Therefore, it is of great significance for the alcohol products brewing industry to explore the effects of ethanol stress on the growth metabolism of . In this study, the effects of ethanol stress on the growth, esters production ability, cell membrane integrity and reactive oxygen species (ROS) metabolism of NCU003 were studied. Our results showed that ethanol stress could inhibit the growth, reduce the ability of non-ethyl ester compounds production and destroy the cell morphology of NCU003. The results also showed that 9% ethanol stress produced excessive ROS and then increased the activities of antioxidant enzymes (superoxide dismutase, catalase, aseorbateperoxidase and glutathione reductase) compared to the control group. However, these increased antioxidant enzyme activities could not prevent the damage caused by ROS to NCU003. Of note, correlation results indicated that high content of ROS could promote the accumulation of malondialdehyde content, resulting in destruction of the integrity of the cell membrane and leading to the leakage of intracellular nutrients (soluble sugar and protein) and electrolytes. These results indicated that the growth and the non-ethyl ester compounds production ability of could be inhibited under ethanol stress by accumulating excessive ROS and the destruction of cell membrane integrity in .
PubMed: 36429336
DOI: 10.3390/foods11223744 -
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 -
Chemosphere Dec 2021Microbial fuel cell (MFC) is an optimistic fuel cell technology that applies microorganism's biochemical catalytic activities in consuming organic substrate and produce... (Review)
Review
Microbial fuel cell (MFC) is an optimistic fuel cell technology that applies microorganism's biochemical catalytic activities in consuming organic substrate and produce electricity. In the past, several researchers have reported power generation from Saccharomyces cerevisiae, but nowadays, most of the studies are centred around bacterial biofilms (prokaryotes) as anode biocatalyst. Yeast (a eukaryote) has also been applied as a biocatalyst in MFCs as they are non-pathogenic, easy to handle and tolerant to various environmental conditions. Yeast strains such as Arxula adeninvorans, Candida melibiosica, Hansenula polymorpha, Hansenula anomala, Kluyveromyces marxianus and Saccharomyces cerevisiae have been utilized in MFCs. This review summarizes the application of yeast as an anode biocatalyst together with a discussion on the mechanism of electron transfer from yeast cells to the anode and highlights the techniques applied in improving the efficiency of yeast-based MFCs. The recent challenges and benefits of utilizing yeast in MFCs have been also encapsulated in this review.
Topics: Bioelectric Energy Sources; Candida; Electricity; Electrodes; Kluyveromyces; Saccharomyces cerevisiae; Saccharomycetales
PubMed: 34216925
DOI: 10.1016/j.chemosphere.2021.131383 -
Journal of Environmental Management Mar 2024Sweet sorghum, as a seasonal energy crop, is rich in cellulose and hemicellulose that can be converted into biofuels. This work aims at investigating the effects of...
Sweet sorghum, as a seasonal energy crop, is rich in cellulose and hemicellulose that can be converted into biofuels. This work aims at investigating the effects of synergistic regulation of Pichia anomala and cellulase on ensiling quality and microbial community of sweet sorghum silages as a storage and pretreatment method. Furthermore, the combined pretreatment effects of ensiling and ball milling on sweet sorghum were evaluated by microstructure change and enzymatic hydrolysis. Based on membership function analysis, the combination of P. anomala and cellulase (PA + CE) significantly improved the silage quality by preserving organic components and promoting fermentation characteristics. The bioaugmented ensiling with PA + CE restructured the bacterial community by facilitating Lactobacillus and inhibiting undesired microorganisms by killer activity of P. anomala. The combined bioaugmented ensiling pretreatment with ball milling significantly increased the enzymatic hydrolysis efficiency (EHE) to 71%, accompanied by the increased specific surface area and decreased pore size/crystallinity of sweet sorghum. Moreover, the EHE after combined pretreatment was increased by 1.37 times compared with raw material. Hence, the combined pretreatment was demonstrated as a novel strategy to effectively enhance enzymatic hydrolysis of sweet sorghum.
Topics: Hydrolysis; Sorghum; Silage; Cellulase; Fermentation; Saccharomycetales
PubMed: 38359627
DOI: 10.1016/j.jenvman.2024.120327 -
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 -
International Journal of Environmental... Mar 2023The main goal of wastewater treatment is to significantly reduce organic compounds, micronutrients (nitrogen and phosphorus) and heavy metals and other contaminants...
The main goal of wastewater treatment is to significantly reduce organic compounds, micronutrients (nitrogen and phosphorus) and heavy metals and other contaminants (pathogens, pharmaceuticals and industrial chemicals). In this work, the efficiency of removing different contaminants (COD, NO, NO, NH, PO, SO, Pb, Cd) from synthetic wastewater was tested using five different yeast strains: CMGBP16 (P1), S228C (P2), CM6B70 (P3), CMGB234 (P4) and CMGB88 (P5). The results showed a removal efficiency of up to 70% of COD, 97% of nitrate, 80% of nitrite, 93% of phosphate and 70% of sulfate ions for synthetic wastewater contaminated with Pb (43 mg/L) and Cd ions (39 mg/L). In contrast, the results showed an increase in ammonium ions, especially in the presence of Pb ions. The yeast strains showed a high capacity to reduce Pb (up to 96%) and Cd (up to 40%) ions compared to the initial concentrations. In presence of a crude biosurfactant, the removal efficiency increased up to 99% for Pb and 56% for Cd simultaneously with an increase in yeast biomass of up to 11 times. The results, which were obtained in the absence of aeration and in neutral pH conditions, proved a high potential for practical applications in the biotreatment of the wastewater and the recovery of Pb and Cd ions, with a high benefit-cost ratio.
Topics: Wastewater; Saccharomyces cerevisiae; Cadmium; Biodegradation, Environmental; Lead; Metals, Heavy; Phosphates
PubMed: 36981703
DOI: 10.3390/ijerph20064795 -
Heliyon May 2024The growing amount of plastic waste requires new ways of disposal or recycling. Research into the biodegradation of recalcitrant plastic polymers is gathering pace....
The growing amount of plastic waste requires new ways of disposal or recycling. Research into the biodegradation of recalcitrant plastic polymers is gathering pace. Despite some progress, these efforts have not yet led to technologically and economically viable applications. In this study, we show that respirometric screening of environmental fungal isolates in combination with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy can be used to identify new strains with the potential for the degradation of plastic polymers. We screened 146 fungal strains, 71 isolated from car repair shops, an environment rich in long-chain hydrocarbons, and 75 isolated from hypersaline water capable of growing at high concentrations of NaCl. When grown in a minimal medium with no carbon source, some strains produced significantly more CO when a pure plastic polymer was added to the medium, some only at high salinity. A selection of these strains was shown by FTIR and Raman spectroscopy to alter the properties of plastic polymers: sp. EXF-13502 on polyamide, EXF-13500 on polypropylene, sp. EXF-10630 on low-density polyethylene and EXF-6848 on polyethylene terephthalate. Respirometry in combination with specific spectroscopic methods is an efficient method for screening microorganisms capable of at least partial plastic degradation and can be used to expand the repertoire of potential plastic degraders. This is of particular importance as our results also show that individual strains are only active against certain polymers and under certain conditions. Therefore, efficient biodegradation of plastics is likely to depend on a collection of specialized microorganisms rather than a single universal plastic degrader.
PubMed: 38803974
DOI: 10.1016/j.heliyon.2024.e31130 -
Microorganisms Sep 2019This experiment was carried out to identify and select pectinolytic yeasts that have potential use as a starter culture for coffee fermentation during wet processing....
This experiment was carried out to identify and select pectinolytic yeasts that have potential use as a starter culture for coffee fermentation during wet processing. The coffee fruit was fermented for 48 h at 28 °C and a sample was taken from the fermented solution and spread onto yeast extract-peptone-dextrose agar (YPDA) media and incubated at 28 °C. A total of 28 yeasts were isolated, eight of which had the ability to produce pectinase enzymes. The species of those eight yeasts were molecularly identified and confirmed. These yeasts are (strain KNU18Y3), (strain KNU18Y4), (strain KNU18Y5 and KNU18Y6) (strain KNU18Y7 and KNU18Y8), and (strain KNU18Y12 and KNU18Y13). The pectin degradation index of (strain KNU18Y4), (strain KNU18Y3), and (strain KNU18Y6) were higher compared to the others, at 178%, 160%, and 152%, respectively. The pectinase enzyme assays were made on two growth media: coffee pulp media (CPM) and synthetic pectin media (SPM). (strain KNU18Y4) and (strain KNU18Y3) had great potential in producing polygalacturonase (PG) and pectin lyase (PL) compared to others in both media. However, strains (KNU18Y12 and KNU18Y13) produced higher pectin methylesterase (PME). Using MEGA 6 software, the phylogenetic trees were constructed to determine the evolutionary relationship of newly identified yeasts from our experiment and previously published yeast species. The sequences of the yeasts were deposited in the National Center for Biotechnology Information (NCBI) database.
PubMed: 31569406
DOI: 10.3390/microorganisms7100401