• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.329-336
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• 1996

From five years' previous work, the fungal isolates of Scopulariopsis were reported to be important flora at the late stage of meju fermentation. Mainly, the white or pale brown powders of spore mass of these fungi were observed on the surfaces of rectangular mejus, and to be an important sign for well-done Korean traditional home - made mejus. Out of the five isolates previously collected and stored, two kinds of Scopulariopsis isolates were identified as S. brevicauli and S. fusca. The microscopic differences between two were found to be branching patterns of annellophore and ornamentations of spore wall (warty and smooth). However, the intermediate form between two ornamentations of spore wall were also observed in our isolates. This observation was consistent with other result made from the protein electrophoresis. The isolates of Scopulariopsis were considered to be similar or superior to those of Aspergillus species, as compared with production of protease and amylase related enzymes. Thus, these isolates were speculated to be important fungi in Korean traditional home - made meju fermentation and also in production of protease and amylase.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.691-694
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• 2007

Acetic acid and butyric acid were produced by the anaerobic fermentation of soil mixed with wheat or rice bran. The concentration of acetic acid produced in the wheat and rice bran-treated soil was 31.2mM and 8mM, respectively, whereas the concentration of butyric acid in the wheat and rice bran-treated soil was 25.0mM and 8mM, respectively. The minimal fungicidal concentration (MFC) for all the fungal strains was 40-60mM acetic acid, 20-40mM butyric acid, and 40-60mM mixture of acetic acid: butyric acid (1:1, v/v). Consequently, the efficacy of mixing wheat-bran with soil to control soil diseases was demonstrated.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1197-1205
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• 2024

Filamentous fungi are important cell factories for the production of high-value enzymes and chemicals for the food, chemical, and pharmaceutical industries. Under submerged fermentation, filamentous fungi exhibit diverse fungal morphologies that are influenced by environmental factors, which in turn affect the rheological properties and mass transfer of the fermentation system, and ultimately the synthesis of products. In this review, we first summarize the mechanisms of mycelial morphogenesis and then provide an overview of current developments in methods and strategies for morphological regulation, including physicochemical and metabolic engineering approaches. We also anticipate that rapid developments in synthetic biology and genetic manipulation tools will accelerate morphological engineering in the future.

• Journal of Life Science
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• v.22 no.2
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• pp.232-238
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• 2012

Kumjungsansung-Makgeolli$^{(R)}$ is a traditional Korean rice wine that is fermented from traditional nuruk and rice. In this study, we performed the PCR-denaturing gradient gel electrophoresis (DGGE) analysis targeting the 16S and 28S rRNA genes to characterize bacterial and fungal diversity during Makgeolli fermentation. The predominant bacteria in the PCR-DGGE profile during Makgeolli fermentation were Lactobacillus spp. (Lactobacillus curvatus, L. kisonensis, L. plantarum, L. sakei, and L. gasseri), Pediococcus spp. (P. acidilactici, P. parvulus, P. agglomerans, and P. pentosaceus), Pantoea spp. (P. agglomerans and P. ananatis), and Citrobacter freundii; these were identified on the base of analysis of 16S rRNA gene sequences. The dominant bacterium during Makgeolli fermentation was L. curvatus. The predominant fungi in PCR-DGGE profile during Makgeolli fermentation were Pichia kudriavzevii, Saccharomyces cerevisiae, Asidia idahoensis, Kluyveromyces marxianus, Saccharomycopsis fibuligera, and Torulaspora delbrueckii, and these were identified on the basis of analysis of 28S rRNA gene sequences. The dominant fungal species during Makgeolli fermentation changed from P. kudriavzevii at 0-2 days incubation to S. cerevisiae at 3-6 days incubation. This study suggests that PCR-DGGE analysis could be a suitable tool for the understanding of microbial diversity and structure during Makgeolli fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1528-1539
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• 2019

Objective: To evaluate the effects on microbial diversity and biochemical parameters of gradually increasing temperatures, from $5^{\circ}C$ to $25^{\circ}C$ on corn silage which was previously fermented at ambient or low temperature. Methods: Whole-plant corn silage was fermented in vacuum bag mini-silos at either $10^{\circ}C$ or $20^{\circ}C$ for two months and stored at $5^{\circ}C$ for two months. The mini-silos were then subjected to additional incubation from $5^{\circ}C$ to $25^{\circ}C$ in $5^{\circ}C$ increments. Bacterial and fungal diversity was assessed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiling and biochemical analysis from mini-silos collected at each temperature. Results: A temperature of $10^{\circ}C$ during fermentation restricted silage fermentation compared to fermentation temperature of $20^{\circ}C$. As storage temperature increased from $5^{\circ}C$ to $25^{\circ}C$, little changes occurred in silages fermented at $20^{\circ}C$, in terms of most biochemical parameters as well as bacterial and fungal populations. However, a high number of enterobacteria and yeasts (4 to $5\;log_{10}$ colony forming unit/g fresh materials) were detected at $15^{\circ}C$ and above. PCR-DGGE profile showed that Candida humilis predominated the fungi flora. For silage fermented at $10^{\circ}C$, no significant changes were observed in most silage characteristics when temperature was increased from $5^{\circ}C$ to $20^{\circ}C$. However, above $20^{\circ}C$, silage fermentation resumed as observed from the significantly increased number of lactic acid bacteria colonies, acetic acid content, and the rapid decline in pH and water-soluble carbohydrates concentration. DGGE results showed that Lactobacillus buchneri started to dominate the bacterial flora as temperature increased from $20^{\circ}C$ to $25^{\circ}C$. Conclusion: Temperature during fermentation as well as temperature during storage modulates microorganism population development and fermentation patterns. Silage fermented at $20^{\circ}C$ indicated that these silages should have lower aerobic stability at opening because of better survival of yeasts and enterobacteria.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.256-261
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• 2006

Soybeans were fermented with Monascus sp. to select strain with highest mevinolin production through solidstate fermentation. Monascus pilosus IFO 480 showed highest yield of 2.2 mg mevinolin per g dry weight without citrinin, toxic fungal secondary metabolite, as byproduct. Nutrient broth used for soybean fermentation with Monascus sp. was composed of 3.4 rice powder, 1.1 peptone, 2.6 glycine, 12.9 glucose, initial pH 6.0 (%, w/v). Mevinolin was present in fermentation substrate largely as hydroxy carboxylate form (open lactone, 91.8-96.8%), which is used as hypocholesterolemic agent. Production of mevinolin continued up to 50 days fermentation time at $30^{\circ}C$.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.78-84
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• 2011

To develop new functional traditional rice wines using Gugija and Liriope tuber as raw materials, screenings of optimal fungal nuruk and alcohol fermentative yeast for brewing of Gugija-L. tuber traditional rice wine were performed with investigation of optimal fermentation condition. Finally, we selected commercial SJ nuruk and Saccharomyces cerevisiae C-2 as optimal nuruk and yeast for Gugija-L. tuber traditional rice wine. Furthermore, a new antihypertensive and anti-gout Gugija-L. tuber traditional rice wine was produced when 3% of Jangmyong Gugija and L. tuber No.1 were added into cooked rice and then fermented at $25^{\circ}C$ for 5 days with SJ nuruk and S. cerevisiae C-2.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1445-1453
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• 2013

The scale-up criterion of constant oxygen mass transfer coefficient ($k_La$) was applied for the production of itaconic acid (IA) in a 50 L pilot-scale fermentor by the fungal cells of Aspergillus terreus. Various operating conditions were examined to collect as many $k_La$ data as possible by adjusting the stirring speed and aeration rate in both 5 L and 50 L fermentor systems. In the fermentations performed with the 5 L fermentor, the highest IA production was obtained under the operating conditions of 200 rpm and 1.5 vvm. Accordingly, we intended to find out parallel agitation and aeration rates in the 50 L fermentor system, under which the $k_La$ value measured was almost identical to that ($0.02sec^{-1}$) of the 5 L system. The conditions of 180 rpm and 0.5 vvm in the 50 L system turned out to be optimal for providing almost the same volumetric amount of dissolved oxygen (DO) into the fermentor, without causing shear damage to the producing cells due to excessive agitation. Practically identical fermentation physiologies were observed in both fermentations performed under those respective operating conditions, as demonstrated by nearly the same values of volumetric ($Q_p$) and specific ($q_p$) IA production rates, IA production yield ($Y_{p/s}$), and specific growth rate (${\mu}$). Specifically, the negligible difference of the specific growth rate (${\mu}$) between the two cultures (i.e., $0.029h^{-1}$ vs. $0.031h^{-1}$) was notable, considering the fact that ${\mu}$ normally has a significant influence on $q_p$ in the biosynthesis of secondary metabolites such as itaconic acid.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.41-45
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• 2014

In the present study, red ginseng extracts were fermented by Paecilomyces tenuipes and the protopanaxdiol-type ginsenosides in the extracts were bio-transformed to F2, Rg3, Rg5, Rk1, Rh2, and CK determined by a high-pressure liquid chromatography analysis. It indicates that P. tenuipes is a microorganism to biotransform protopanaxdiol-type ginsenosides to their less glucosidic metabolites. Other biotransformed metabolites during fermentation were also analyzed using a GC-MS and identified as 2-methyl-benzaldehyde, 4-vinyl-2-methylphenol, palmitic acid, and linoleic acid. Antiulcerogenic activity of the fermented red ginseng extract (FRGE) on gastric mucosal damage induced by 0.15 M HCl in ethanol in rats was evaluated. FRGE was shown to have a potent protective effect on gastritis with 60.5% of inhibition rate at the dose of 40 mg/kg when compared to 54.5% of the inhibition rate at the same dose for stillen, the currently used medicine for treating gastritis. Linoleic acid showed a strong inhibition on gastritis with 79.3% of inhibition rate at the dose of 40.0 mg/kg. FRGE exhibited a distinct anticancer activity including growth inhibition of the two human colon cancer cells HT29 and HCT116. HT29 cells were less susceptible to FRGE in comparison with HCT116 cells. Taken together, fungal fermentation of the red ginseng extract induced hydrolysis of some ginsenosides and FRGE exhibited potent antiulcerogenic and anticancer activities. These results refer to use FRGE as a new source for treating human diseases.

• Journal of Microbiology and Biotechnology
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• v.23 no.12
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• pp.1654-1663
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• 2013

Rice straw is closely associated with meju fermentation and it is generally known that the rice straw provides meju with many kinds of microorganisms. In order to elucidate the origin of meju fungi, the fungal diversity of rice straw was examined. Rice straw was collected from 12 Jang factories where meju are produced, and were incubated under nine different conditions by altering the media (MEA, DRBC, and DG18), and temperature ($15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$). In total, 937 strains were isolated and identified as belonging to 39 genera and 103 species. Among these, Aspergillus, Cladosporium, Eurotium, Fusarium, and Penicillium were the dominant genera. Fusarium asiaticum (56.3%), Cladosporium cladosporioides (48.6%), Aspergillus tubingensis (37.5%), A. oryzae (31.9%), Eurotium repens (27.1%), and E. chevalieri (25.0%) were frequently isolated from the rice straw obtained from many factories. Twelve genera and 40 species of fungi that were isolated in the rice straw in this study were also isolated from meju. Specifically, A. oryzae, C. cladosporioides, E. chevalieri, E. repens, F. asiaticum, and Penicillium polonicum (11.8%), which are abundant species in meju, were also isolated frequently from rice straw. C. cladosporioides, F. asiaticum, and P. polonicum, which are abundant in the low temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $15^{\circ}C$ and $25^{\circ}C$, whereas A. oryzae, E. repens, and E. chevalieri, which are abundant in the high temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $25^{\circ}C$ and $35^{\circ}C$. This suggests that the mycobiota of rice straw has a large influence in the mycobiota of meju. The influence of fungi on the rice straw as feed and silage for livestock, and as plant pathogens for rice, are discussed as well.