• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.318-324
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• 1995

The evolutionary relationships of the genus Trichoderma and related taxa were assessed using partial sequencing of 18S ribosomal RNA. Phylogenetic tree divided into three major groups; 1. Saccharomyces cerevisiae-Geotrichum klebahnii-Alternaria mali group; 2. Neurospora crassa-Aspergillus-Penicillium-Chrysosporium pannorum-Scopulariopsis sp. group; 3. Trichoderma group. The genus Trichoderma seemed to be phylogenetically separated from Saccharomyces cerevisiae, Aspergillus and Penicillium groups, and have passed through it's own evolutionary pathway.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.722-726
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• 2005

The use of isolated wine yeasts in winemaking processes is preferable to spontaneous fermentation. Selection criteria of wine yeast strains depend also on capacity and rate of fermentation and on alcohologenic capabilities. Our studies have described the dynamics of fermentation of wine musts by some isolated wine yeast strains of Saccharomyces genus: strains 6 and 8 of S. cerevisiae var. ellipsoideus (S. ellipsoideus) and strains 5 and 7 of S. bayanus var. oviformis (S. oviformis). All have high technological properties and all are adapted for the specific pedoclimatic conditions of some areas of Sibiu viticultural region. The selected strains were used as inocula to ferment Sauvignon, Muscat Ottonel, Rose Traminer, and Pino Gris musts in controlled laboratory conditions. It was found that higher initial oxygen concentration in must is necessary to accelerate the fermentation of all the wine yeast strains studied. In order to obtain quality wines, strains with considerable fermentative capacity, high alcohologenic capabilities, and a good conversion efficiency are recommended.

• Journal of Naturopathy
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• v.8 no.1
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• pp.1-10
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• 2019

Purpose: The purpose of this study was to investigate the increase or decrease of important intestinal beneficial bacteria and inhibitory bacteria in 30 stools of clinical subjects after ingesting Zen fermentation broth as a mixed microbial fermentation solution for eight weeks. Methods: Intestinal bacteria were identified by PCR amplification using specific primers. Results: Bifidobacterium genus gi% of test group ingested Zen-fermented broth was 55.15% before and 70.1% after ingestion, so it was a significant difference (p<.009). Lactobacillus genus of the test group was 46.87% before and 60.91% after ingestion, it was a significant difference (p<.01). Clostridium genus of the test group was 85.64% before and 65.99% after ingestion. There was a significant difference (p<.017) as the pre-post-difference decreased to -19.65%. Bacteroides genus of the test group was 17.11% before and 20.22% after ingestion. There was a significant difference (p<.048) as the pre-post-difference increased to 3.11%. Prevotella genus of the test group was 14.01% before and 16.79% after ingestion, so it was not a significant difference. Conclusions: Intestinal bacteria increased the proliferation of beneficial bacteria and suppressed harmful bacteria in the intestines after ingesting the Zen-fermented broth of the mixed microorganism. The Zen fermentation broth evaluated as a beneficial drink for intestinal health.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.219-224
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• 1992

The changes of yeast population were investigated in Mul-kimchi containing 3% salt, fermented at $15^{\circ}C$. The total viable count increased to the maximum at the optimum ripening period and then decreased rapidly. Among twenty-nine strains isolated at the optimum ripening period, the yeasts of genus Saccharomyces were predominant. The growth of five strains, Saccharomyces saitoanus Y17, Saccharomyces capensis Y29, Saccharomyces chevalieri Y13, Kluyveromyces fragilis Y2, Torulopsis candida Y9, was measured in mixed culture with each selected lactic strains, hctobaczllus plantarum Lp2, Pedzococcus pentosaceus PI, Leuconostoc mesenteroides Lu5. The results indicated that all the yeasts tested were inhibited significantly by lactic strains, however the sensitivity of yeast strains varied greatly.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.56-64
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• 2015

It has been known for some time to the wine industry that non-Saccharomyces yeasts play an important role in increasing volatile components through the secretion of extracellular enzymes. The objective of this study was to investigate what types of enzymes are produced by 1,007 non-Saccharomyces yeast strains isolated from Korean fermented foods. Among 1,007 yeast strains, the 566, 45 and 401 strains displayed β-glucosidase, glucanase and protease activity, respectively. In addition, the 563 and 610 strains possessed tolerances against cerulenin and TFL, and the 307 strain was tolerant to 15% ethanol. Yeasts producing harmful biogenic amines and hydrogen sulfide were excluded from further study, and eventually 12 yeast strains belonging to the genera Wickerhamomyces, Hanseniaspora, Pichia, Saccharomyces were identified, based on the 26S rRNA gene sequences. Among the 12 strains, the 9 and 5 strains possessed glucose and ethanol tolerance, respectively. Yeasts belonging to the genus Saccharomyces produced more than 8% alcohol, but non-Saccharomyces yeasts produced only 3% alcohol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1109-1114
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• 2013

Microbial community analysis was performed on Tarak, a traditional Korean fermented milk product, by 16S rDNA cloning and pyrosequencing to obtain basic data for the standardization and systematization of the Tarak manufacturing process. Microbial analysis of the prokaryotic community revealed a slight difference in microbial abundance between Bontarak (n) and Tarak (n+1), but Firmicute was dominant at the phylum level. At the genus level, the Lactobacillus and Leuconostoc genera constituted over 90% of the population in Bontarak, but Lactococcus was the dominant genus in Tarak. Bontarak and Tarak showed further differences at the species level. Leuconostoc citreum was the dominant species in Bontarak, constituting 40% of the population. In eukaryotic community analysis, all samples were composed of Ascomycota at the phylum level. At the genus level, Saccharomyces was dominant in Bontarak (85% of the population), while Issatchenkia was dominant in Tarak (95% of the population). At the species level, Saccharomyces cerevisiae was detected at a relative abundance in Bontarak (82%), and Pichia kudriavzevii was the dominant species in Tarak, with a relative abundance of 95%. Sensory evaluation indicated that Tarak had a better appearance and texture than Bontarak. As sweetness was not significantly different between the two samples just slightly higher in Tarak, this was likely due to a significant decrease in sourness in Tarak. These results suggest that the microbial community used affects the quality of Tarak produced. Thus, a stable microbial community must be maintained for the production of Tarak with consistent quality.

• Korean Journal of Microbiology
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• v.8 no.3
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• pp.95-102
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• 1970

From the crops Drosophila collected in Mt. Sokni and Mt.Kyeryong, 7 strains were isolated and then 6 species of wild yeast were identified. 1) Of these six species of wild yeasts two were to be of genus Saccharomyces(Ascosporgenous), two Torulopsis and two Trichosporon (both genuses of Asporogenous). 2) It was found that the fermentation of the wild yeasts isolated from Drosophila was much better than that of any others ; in particular, S. florentinus and S. cerevisiae were good in fermenting maltose. 3) After being cultivated in malt extract agar medium at $25^{\circ}C$ for 3 days, the vegetative cells were found to be big but Torulopsis cells small. 4) It was also observed that the species of yeasts used fro food by Drosophila largely depends on genus and species of Drophila. 5) Of the yeasts isolated from the Drosophila, Trichosporon capitatum and Torulopsis dattila, which has not previously been recorded, were identified. 6) It is believed, therfore, that S.florentinus, powerful in fermenting maltose, will be extremely useful in terms of industrial application.

• Journal of Life Science
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• v.20 no.5
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• pp.683-690
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• 2010

The yeast strains of Saccharomyces diastaticus produce one of three isozymes of an extracellular glucoamylase I, II or III, a type of exo-enzyme which can hydrolyse starch to generate glucose molecules from non-reducing ends. These enzymes are encoded by the STA1, STA2 and STA3 genes. Another gene, sporulation-specific glucoamylase (SGA), also exists in the genus Saccharomyces which is very homologous to the STA genes. The SGA has been known to be produced in the cytosol during sporulation. However, we hypothesized that the SGA is capable of being secreted to the extracellular region because of about 20 hydrophobic amino acid residues at the N-terminus which can function as a signal peptide. We expressed the cloned SGA gene in S. diastaticus YIY345. In order to compare the biochemical properties of the extracellular glucoamylase and the SGA, the SGA was purified from the culture supernatant through ammonium sulfate precipitation, DEAE-Sephadex A-50, CM-Sephadex C-50 and Sephadex G-200 chromatography. The molecular weight of the intact SGA was estimated to be about 130 kDa by gel filtration chromatography with high performance liquid chromatography (HPLC) column. Sodium dedecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed it was composed of two heterogeneous subunits, 63 kDa and 68 kDa. The deglycosylation of the SGA generated a new 59 kDa band on the SDS-PAGE analysis, indicating that two subunits are glycosylated but the extent of glycosylation is different between them. The optimum pH and temperature of the SGA were 5.5 and $45^{\circ}C$, respectively, whereas those for the extracellular glucoamylase were 5.0 and $50^{\circ}C$. The SGA were more sensitive to heat and SDS than the extracellular glucoamylase.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.165-173
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• 2011

Five types of meju were prepared from 100% defatted soybean (DFSG0), a mixture of 90% DFS and 10% glasswort (DFSG1), a mixture of 80% DFS and 20% glasswort (DFSG2), a mixture of 70% DFS and 30% glasswort (DFSG3), and a mixture of 60% DFS and 40% glasswort (DFSG4). Five types of kanjang were separately prepared from the 5 types of meju by ripening in brine for 6 months. The contents of certain minerals (Mg, Ca, Fe, Mn, and Zn), organic acids (citric acid, malic acid) and the antioxidative effects in the kanjang were increased in proportion to the glasswort content in the meju. However, the free amino acid contents in the kanjang were reduced in proportion to the glasswort content in the meju. DFSG1- and DFSG2-kanjang did not show distinct differences from DFSG0-kanjang based on aroma, flavor, and taste that were compared simply by panel tests. The bacterial and fungal community in the fermented meju and kanjang was not affected by the addition of glasswort to the meju-making process. Bacteria belonging to the Lactobacillus and Bacillus genera and the Lactobacillus family predominated, and yeasts belonging to the Saccharomyces genus and fungi belonging to the Aspergillus genus predominated in the fermented meju and kanjang. In conclusion, the glasswort was a supplement that nutritionally improved the kanjang (except for free amino acid contents) but didn't influence the growth of microorganisms that are responsible for the fermentation of meju and kanjang.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.128-133
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• 1990

The chromatin of all higher eukaryotic cells contains a group of very basic low-mole-cular weight proteins, the histones. But much less is known about histones in lower eukaryotes. Our purpose was to study the histones of the genus Rhizopus. After isolation and purification of nucleoprotein the basic nucleoproteins were analyzed by gel electrophoresis, in sodium dodecyl sulfate as well as acid/urea gels and compared with calf thymus histones. Their electrophoretic mobility in polyacrylamide gel indicate that they are histone homologous, although not identical, to the H2A, H2B, H3 and H4 histones of mammals with the exception of H1. The result suggests that Rhizopus thus appears to contain histone proteins which are homologous to the histones from in higher eukaryotes. The similarity between the calf thymus histone H1 and the Rhizopus high band group remains to be discussed.