• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.383-390
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• 2010

A newly isolated active producer of raw-starch-digesting amyloytic enzymes, Rhizopus microsporus var. chinensis CICIM-CU F0088, was screened and identified by morphological characteristics and molecular phylogenetic analyses. This fungus was isolated from the soil of Chinese glue pudding mill, and produced high levels of amylolytic activity under solid-state fermentation with supplementation of starch and wheat bran. Results of thin-layer chromatography showed there are two kinds of amyloytic enzymes formed by this strain, including one $\alpha$-amylase and two glucoamylases. It was found in the electron microscope experiments that the two glucoamylases can digest raw corn starch and have an optimal temperature of $70^{\circ}C$. These results signified that amyloytic enzymes secreted by strain Rhizopus microsporus var. chinensis CICIM-CU F0088 were types of thermostable amyloytic enzymes and able to digest raw corn starch.

• Journal of Microbiology and Biotechnology
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• 제24권2호
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• pp.177-187
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• 2014

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (> $150{\mu}m$), soy bean meal (SB), corn meal (< $150{\mu}m$) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

• 미생물학회지
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• 제22권3호
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• pp.197-205
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• 1984

After the previous paper, this chromosomal studies on the fungi were dealt with 17 species in genus of Rhizopus. The results are sumarized as the followings; The haploid chromosome number of 17 species were confirmed as of 6(Rh. oligosporus), 8(Rh. homothallicus, Rh. liquefaciens, Rh. shanghaiensis, Rh, acetorinus), 12(Rh. microsporus, Rh. pseudochinensis, Rh, rhizopodiformis, Rh, thermosus, and Rh. kazanensis), 14(Rh. stolonifer), and 16(Rh. suinus), respectively. Referring to the above fact and the previous paper, it is strongly presumed that the basic chromosome number of Rhizopus are 4.

• Journal of Microbiology
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• 제41권2호
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• pp.157-160
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• 2003

To estimate genetic relationships within the genus Rhizopus, genetic variations in 20 strains were investigated by DGGE and PCR-RFLP of rDNA ITS region (ITSI, ITS2,5.8S). The size of the amplified products showed the interspecific polymorphisms, 650 bp,700 bp, and 900 bp. The DGGE approach allowed the separation of PCR amplicons of the same length according to their sequence variations. When the rDNA ITS region was digested with six restriction enzymes, 20 strains were classified into five RFLP haplotypes. The range of similarity between the 20 strains by PCR-RFLP was 42.3-100%. Based on the results of DGGE aud PCR-RFLP, the 20 strains were divided into four groups, R. oryzae, R. stolonifer, R. microsporus and R. homothallicus. Further study of R. homothallicus is required.

• 한국식품위생안전성학회지
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• 제38권2호
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• pp.63-68
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• 2023

본 연구에서는 저장 조건이 고춧가루 중 곰팡이 생존에 미치는 영향을 분석하였다. 고춧가루에 A. terreus, A. flavus, R. microsporus, A. fumigatus, A. niger, A. ochraceus 등 총 6종의 곰팡이를 접종하여 균액 농도가 4-6 log CFU/g이 되도록 하였다. 곰팡이를 접종한 고춧가루는 Clean bench에 건조하여 지퍼백에 포장한 후 -20℃, 5℃, 15℃, 25℃에 저장하였다. Clean bench에 건조한 고춧가루의 수분활성도는 0.502±0.001이었다. A. terreus 등 균주 6종 모두 25℃에서 가장 먼저 곰팡이가 사멸하였으며, -20℃에서 가장 마지막에 사멸하거나 168일 동안 사멸하지 않았다. 따라서 본 연구 결과, 고춧가루의 수분활성도를 0.6이하로 건조한 후 지퍼백에 소분하여 상온에 보관하는 것이 곰팡이로부터 안전할 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제27권8호
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• pp.1409-1418
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• 2017

Two typical microbial communities from Chinese rice wine fermentation collected in Yichang city and Suzhou city in China were investigated. Both communities could ferment glutinous rice to rice wine in 2 days. The sugar and ethanol contents were 198.67 and 14.47 mg/g, respectively, for rice wine from Yichang city, and 292.50 and 12.31 mg/g, respectively, for rice wine from Suzhou city. Acetic acid and lactic acid were the most abundant organic acids. Abundant fungi and bacteria were detected in both communities by high-throughput sequencing. Saccharomycopsis fibuligera and Rhizopus oryzae were the dominant fungi in rice wine from Suzhou city, compared with R. oryzae, Wickerhamomyces anomalus, Saccharomyces cerevisiae, Mucor indicus, and Rhizopus microsporus in rice wine from Yichang city. Bacterial diversity was greater than fungal diversity in both communities. Citrobacter was the most abundant genus. Furthermore, Exiguobacterium, Aeromonas, Acinetobacter, Pseudomonas, Enterobacter, Bacillus, and Lactococcus were highly abundant in both communities.

• Journal of Microbiology and Biotechnology
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• 제20권8호
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• pp.1226-1229
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• 2010

Glyceollins, one of the inducible phytoalexins produced by plants, were induced in a number of varieties of Korean soybean through fungal infection. Of the tested soybean varieties, Tae-Kwang, though not the most productive, was found to be currently the most suitable for the induction of glyceollins. Amongst the fungal species, Rhizopus microsporus var. oligosporus was seen to be the most effective elicitor. Halved soybean seeds produced glyceollins upon fungal infection; however, chopped soybeans and homogenized soybeans did not produce significant quantities of glyceollins.

• 한국식품위생안전성학회지
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• 제37권4호
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• pp.277-284
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• 2022

시판 유통 중인 건조 인삼류(백삼 24점, 홍삼 26점) 포장 제품을 수집하여 곰팡이 발생 조사를 수행하였다. 백삼과 홍삼은 각각 50%와 46%의 시료에서 곰팡이가 검출되었고 검출 시료의 평균 곰팡이 오염도는 각각 0.5와 0.2 log₁₀ CFU/g이었다. 백삼에서는 Penicillium polonicum, P. chrysogenum, Rhizopus microsporus가 각각 18.2%로 우점하였으나 홍삼은 Aspergillus spp.이 87.6%로 우점하였으며 이 중 A. chevalieri가 50.0%로 가장 높았다. 이 중 독성 종으로 알려진 P. polonicum, P. chrysogenum, P. melanoconidium, A. chevalieri 균주의 citrinin 독소 생성 가능성을 분석한 결과, 13 균주 모두 독소 유전자가 검출되지 않았다. 이 결과는 조사한 시료의 곰팡이독소 오염 위험은 매우 낮지만, 건조 인삼류에 곰팡이 오염이 가능함을 보여준다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 추계학술발표대회
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• pp.39-45
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• 2000

It hab been proposed that CHS3-mediated chitin synthesis during the vegitative cell cycle is regulated by CHS4. To investigate direct protein-protein interaction between their coding products, we used yeast two hybrid system and found that a domain of Chs3p was responsible for interaction with Chs4p. This domain, termed MIRC3-4 (maximum interacting region of chs3p with chs4p), spans from 647 to 700 residues. It is well conserved among CHS3 homologs of various fungi such as Candida albicans, Emericella nidulans, Neurospora crassa, Magnaporthe grisea, Ustilago maydis, Glomus versiforme, Exophiala dermatitidis, Rhizopus microsporus. A series of mutaion in the MIRC3-4 resulted in no appearance of chitin ring at the early G 1 phase but did not affect chitin synthesis in the cell wall after cytokinesis. Absence of chitin ring could be caused either by delocalization of Chs3p to the septum or by improper interaction with Chs4p. To discriminate those two, not mutually exclusive, alternatives, mutants cells were immunostained with Chs3p-specific antibody. Some exhibited localization of chs3p to the septum, while others failed. These results indicate that simultaneous localization and activation Chs3p by Chs4p is required for chitin ring synthesis.