• Archives of Pharmacal Research
• /
• v.27 no.6
• /
• pp.624-627
• /
• 2004

A bile acid derivative, methyl chalate （1）, was isolated from EtOAc extract of the fungus Rhizopus oryzae as a cholesterol biosynthesis inhibitor. It showed moderate inhibitory activity on cholesterol biosynthesis in human Chang liver cells. Compound 1 exhibited inhibitory effect on the later step of cholesterol biosynthesis, indicating that its action mode is different from that of statins that act on the HMG-CoA reductase.

• Korean Journal of Microbiology
• /
• v.24 no.1
• /
• pp.38-45
• /
• 1986

Effect of sodium deoxycholate and sodium dodecyl sulfate on Rhizopus oryzae were investigated. Morphological change was obtained by supplement of these surfactants into culture media during the sumerged culture. In accordance with morphological changes, composition of phospholipid was changed. In case of surfactant-free culture, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine were measured more than 95% of total phospholipid. But cardiolipin and phosphatidylinositol were conspicuously increased by treatment of both sufactants. Presence of phospolipase A, C, and D were detected from mycelium. Phospholipase A and D were activated by supplement of sodium deoxycholate and C was activated by sodium dodecyl sulfate. These results were interpreted in respect of polymorphism of phospholipid and membrane stability against solubilization effect of surfactants.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.7
• /
• pp.1002-1008
• /
• 2012

For the production of Korea traditional cereal wine makgeolli, a rice fermentation starter nuruk was Rhizopus oryaze CCS01 commercial nuruk. The carbohydrate content of rice nuruk was higher, the levels of moisture, ash, crude protein, and crude fat were lower. In particular, the saccharifying activity of rice nuruk was 2.2 times higher than commercial nuruk. pH, alcohol, and viable yeast cells of makgeolli made rice nuruk were higher than those of makgeolli made commercial nuruk. In contrast, the levels of acidity, $^{\circ}Brix$, viable lactic acid bacteria (LAB) cells, and browning of makgeolli made rice nuruk were lower than those of makgeolli made commercial nuruk, the alcohol content of glutinous rice (GUR) makgeolli made rice nuruk higher other samples. These results suggest that rice nuruk R. oryzae CCS01 make new type cereal makgeolli.

• The Korean Journal of Mycology
• /
• v.23 no.1 s.72
• /
• pp.86-91
• /
• 1995

Isoenzymatic analysis related with cadmium adaptation and detoxifying mechanism were carried out upon Rhizopus oryzae. When cadmium was added into R. oryzae culture, activities of malate dehydrogenase (MDH) and glucose phosphate isomerase (GPI) related with carbohydrate metabolizing pathways were stimulated. Novel isoenzyme CAT-2 related with removing intracellular toxic peroxides, was induced lately and derepressed very highly. On the other hand, lactate-catabolizing enzymes such as lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH) were repressed. These results strongly suggest that, under cadmium stress, much of derepression of enzymes relating with central metabolism such as TCA cycle that produces high yield of energy and relating with removal of toxic peroxides should be necessary.

• Korean Journal of Environmental Biology
• /
• v.41 no.4
• /
• pp.677-682
• /
• 2023

Milky white spots appeared on red bean leaves in a red bean cultivation area located in Jangyeon-myeon, Goesan-gun, Chungbuk Province. After culturing the pathogen in PDA medium, their morphology was observed, and their genes were BLAST-searched in the National Center for Biotechnology Information (NCBI). The pathogen was identified as a fungus called Rhizopus arrhizus. As a result of reinoculating the isolated pathogen on red beans, the same symptoms as those in the isolated leaves occurred. Characteristic colonies of R. arrhizuson PDA medium initially showed a bright color and then changed to dark gray over time, with mostly spherical sporangia. The sporangiospores were spherical or elliptical, mostly irregular, and small in size. Therefore, based on these results, this disease has not yet been reported in red beans and was called red bean brown leaf blight caused by Rhizopus arrhizus A. Fisch (syn. R. oryzae).

• Research in Plant Disease
• /
• v.20 no.1
• /
• pp.50-53
• /
• 2014

Rhizopus soft rot of lily (Lilium longiflorum) caused by Rhizopus oryzae was observed in the experimental field in Taean Lily Experiment Station in Korea, 2012. The typical symptoms were water-soaked lesions on bottom stem and leaf rot. The lesion rapidly expanded and the plant was softened totally. The fungus grew vigorously at an optimum temperature ($25^{\circ}C$) and brownish colony and black sporangia were formed on potato dextrose agar medium. Sporangiophores formed on end of sporangia were sub-globose, brownish and $6-10{\mu}m$ in size. Sporangia were globose, blackish and $87-116{\mu}m$ in size. Sporangiospores were irregularly oval and sub-globose, brownish $4-8{\mu}m$ in size. On the basis of mycological characteristics, analyzing sequences of internal transcribed spacer region of ribosomal DNA, and pathogenicity test on host plants, the causal fungus was identified as R. oryzae. This is the first report of Rhizopus soft rot on lily caused by R. oryzae in Korea.

• The Korean Journal of Mycology
• /
• v.26 no.4 s.87
• /
• pp.478-486
• /
• 1998

The isolates of Rhizopus collected from Korean traditional fermented food meju and nuruk, were compared with the well known species of Rhizopus donated. The isolates of Rhizopus were identified with the numerical analyses calculated from RAPD-DNA bands, and confirmed with the microscopic observations of morphological features on PDA. The isolates of R. oryzae purchased were segregated through the results of RAPD or the morphological features. The species of R. nigricans, known as an illegitimate species, were different from those of R. stolonife and it is estimated that they are species of Rhizopus, again. According to microscopic observations and the result of RAPD, Some isolates of R. oryzae purchased belong to R. nigricans and are completely different from R. oryzae in their growth. The isolates of R. nigricans included with several isolates of R. oryzae identified for the different phenotypes and were heterogenous. The isolate of R. oligosporus were speculated to be different from morphological features of Rhizopus, but to be similar to the species of Absidia on the apophysis of sporangium. Its sporangiophore or mycelium was observed to be dark black, but the sporangia were not in those of R. oligosporus. The isolates collected from Korean traditional nuruk showed genetic diversity, and also considered to be different tastes in Korean rice wines.

• The Korean Journal of Mycology
• /
• v.14 no.4
• /
• pp.273-280
• /
• 1986

The degree of autolysis and lytic enzyme production in the culture filtrate of Rhizopus oryzae was investigated. The formation of protoplast by using autolytic enzymes from Rh. oryzae was also attempted. Protoplasts were liberated from Rh. oryzae mycelium by lytic enzymes present in autolytic-phase culture filtrate. Maximum release of chitosanase and proteolytic enzyme into culture filtrate during autolysis was corresponded to maximum protoplast-liberating activity. High yields of protoplasts were obtained from 10 hr-age of Rh. oryzae mycelium with 0.5 M mannitol as osmotic stabilizer. The optimum temperature and pH for mycelium digestion were $25{\sim}30^{\circ}C$ and $6.0{\sim}6.5$ respectively. The mycelium of the 18 hours cultures were treated with autolytic enzyme in same volume of osmotic stabilizer at $30^{\circ}C$ for 5 hours and then it was confirmed by scanning electoron microscope that protoplast were produced beside the digesting cell wall of the fungi.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.11 no.6
• /
• pp.522-525
• /
• 2006

Biodiesel conversion from soybean oil reached a maximum of 70% at 18 h using immobilized 1,3-specific Rhizopus oryzae lipase alone. Biodiesel conversion failed to reach 20% after 30 h when immobilized nonspecific Candida rugosa lipase alone was used. To increase the biodiesel production yield, a mixture of immobilized 1,3-specific R. oryzae lipase and nonspecific C. rugosa lipase was used. Using this mixture a conversion of greater than 99% at 21 h was attained. When the stability of the immobilized lipases mixture was tested, biodiesel conversion was maintained at over 80% of its original conversion after 10 cycles.

• Microbiology and Biotechnology Letters
• /
• v.9 no.2
• /
• pp.83-89
• /
• 1981

Several kinds of organic acids, alcohols, aromatic compounds and sugars as carbon sources were tested in order to produce the cell mass of Rhizopus oryzae which is used in part of food processing or organic acid fermentation. Sodium acetate among them was good enough for carbon source as well as glucose under the concentration of one percent. All nitrogenous substances tested such as ammonium, nitrate or organic nitrogen compounds were well used by this strain of Rhizopus oryzae as nitrogen source. Ammonium sulfate among inorganic nitrogen compounds was most utilized as a nitrogen source in glucose or acetate medium. This strain did not require any growth factors such as yeast extract. The following composition of medium was therefore determined in order to produce the cell mass of Rhizopus oryzae: Na-acetate 1 %, (NH$_4$)$_2$SO$_4$ 0.2%, $K_2$HPO$_4$ 0.05%, MgSO$_4$.7$H_2O$ 0.01%, NaCl 0.01% (PH 5.5). The cell wall of mycelium grown in above medium was lysed optimally at pH 6.5 and 5$0^{\circ}C$ by the action of Strepzyme 115-5. On producing protoplast from mycelium by enzymatic action, almost all of the mycelium was damaged after 4hrs of treatment.