• 한국균학회지
• /
• 제24권4호통권79호
• /
• pp.329-336
• /
• 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
• /
• 제17권4호
• /
• pp.691-694
• /
• 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
• /
• 제34권6호
• /
• pp.1197-1205
• /
• 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.

• 생명과학회지
• /
• 제22권2호
• /
• pp.232-238
• /
• 2012

금정산성 막걸리$^{(R)}$는 전통적인 수제누룩과 쌀로부터 발효된 한국의 전통적인 술이다. 본 연구에서는 막걸리 발효기간 동안 세균과 진균의 다양성을 특성화하기 위해 16S와 28S rRNA 유전자를 목적으로 하는 PCRDenaturing Gradient Gel Electrophoresis (PCR-DGGE) 분석을 수행하였다. 막걸리 발효기간 동안 PCR-DGGE profile에서 검출된 세균은 16S rRNA 유전자 서열에 기초한 동정결과 Lactobacillus spp. (L. curvatus, L. kisonensis, L. plantarum, L. sakei 및 L. gasseri), Pediococcus spp. (P. acidilactici, P. parvulus, P. agglomerans및 P. pentosaceus), Pantoea spp. (P. agglomerans 및 P. ananatis) 그리고 Citrobacter freundii로 총 12종이었으며, 배양2일 이후 L. curvatus가 주된 우점 종을 형성하였다. 반면 PCR-DGGE profile에서 검출된 진균은 28S rRNA 유전자 서열에 기초한 동정결과 Pichia kudriavzevii, Saccharomyces cerevisiae, Asidia idahoensis, Kluyveromyces marxianus, Saccharomycopsis fibuligera 및 Torulaspora delbrueckii로 6종이었으며 주된 우점 진균은 배양0일에서 2일에 P. kudriavzevii에서 배양 3일에서 6일에 S. cerevisiae로 전환되었다. 결과적으로 PCR-DGGE분석은 막걸리발효기간 동안 미생물의 구조와 다양성을 이해하는 데 유용한 도구임을 보여주었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제32권10호
• /
• pp.1528-1539
• /
• 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.

• 한국식품과학회지
• /
• 제38권2호
• /
• pp.256-261
• /
• 2006

20여종의 Monascus속의 균주로 부터 mevinolin의 생산능이 우수하면서도 곰팡이 독소성분 citrinin을 생산하지 않는 우량균주를 선발하였으며, 콩시료에 대한 고상발효를 최적화하기 위한 영양배지의 조성물이 검토되었다. 선발된 M. pilosus IFO 480으로 발효시킨 홍국콩 발효물에 함유된 mevinolin의 주요 화합물은, 약리학적 활성형(drug)의 mevinolinic acid 밝혀졌다(91.8%). 따라서 홍국 발효콩은 생체활성형의 항 콜레스테롤 성분을 최대 0.22% 까지 함유하는, 안전한 건강 기능성식품 소재로서의 활용가능성이 높은 것으로 평가할 수 있다.

• 한국균학회지
• /
• 제39권1호
• /
• pp.78-84
• /
• 2011

구기자와 맥문동을 이용하여 새로운 생리기능성 전통주를 개발하고자 항고혈압 활성이 보고된 구기자 3품종과 항통풍성을 가진 맥문동 2품종과 시판 Saccharomyces cerevisiae 3종류와 시판 2종류의 발효제를 이용하여 발효시켜 구기자-맥문동 전통주 제조에 적합한 알콜 발효 효모로 Saccharomyces cerevisiae C-2와 당화효소를 생성하는 진균 발효제로 SJ누룩을 최종 선발 하였다. 또한 이들을 이용한 발효 최적조건으로 구기자-맥문동 첨가량과 발효 최적시간 등을 검토하였다. 최종적으로 장명 구기자와 맥문동 1호를 덧밥에 각각 3%씩 첨가하고 Saccharomyces cerevisiae C-2와 SJ 누룩으로 $25^{\circ}C$에서 5일간 발효시켜 고품질의 기호도가 높고 항고혈압 활성과 항통풍성을 가진 새로운 구기자-맥문동 전통주를 개발하였다.

• Journal of Microbiology and Biotechnology
• /
• 제23권10호
• /
• pp.1445-1453
• /
• 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
• /
• 제57권1호
• /
• pp.41-45
• /
• 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
• /
• 제23권12호
• /
• pp.1654-1663
• /
• 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.