• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.440-445
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• 1993

The fungi SFN 416 strain which produced a stable beta-glucosidase was isolated from nature and identified to Aspergillus niger. Optimal conditions of enzyme reaction were temperature 36C, pH-5.0, reaction time-40 minutes. The enzyme was stable below 60C and in the range of pH 4.5-6.5. The enzyme was greatly inhibitied by Ag+ and slightly activated by Ca2+ (0.5mM) and Cu2+ (5 mM).

• KCI Concrete Journal
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• v.14 no.4
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• pp.171-177
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• 2002

Antifungal agents are used to impart antibacterial or bactericidal properties to commodities and various articles used in industries and can be classified into two broad groups i.e organic and inorganic. Inorganic antifungal agents comprise of Ag, Zn, or Cu, etc. These elements tend to exhibit high level of antifungal activities, non-uniform dispersion in substrates, and have poor properties in expensive and cheap adhesiveness. In this study, the organic antifungal agent was used for the purpose of investigating the antifungal activity of antifungal agent activated-cement mortar (AACM) on the aspergilus niger of various fungus which can be easily discovered in the interiors and exteriors of buildings. In addition, an experiment on the basic physical properties of AACM such as compressive and flexural strength was carried out. The conclusion of this investigation revealed that a dosage increase of antifungal agent exhibits a high inhibitory effect on the aspergilus niger, and although there is a slight decrease in the strength of AACM, the strength of AACM was almost equal to that of inactivated cement mortar.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1066-1070
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• 2001

The PhyA gene, encoding myo-inositol hexakisphosphate phosphohydrolase in Aspergillus niger var. awamori (wild-type), was cloned and sequenced. The cDNA was overexpressed by a multicopy gene expression system in Pichia pastoris KM71. Recombinant, wild-type and commercial phytase from Aspergilus ficuum NRRL 3135 (Natuphos) were purified. The PhyA gene of Aspergillus niger var awamori showed perfect homology to the phytase of Aspergillus ficcum and $97\%$ homology to A. niger var awamori (L02421). Wild-type phytase was highly glycosylated and more thermostable than the other two, while deglycosylated farms of three phytases showed identical molecular weight, 507 kDa. After heating at $80^{\circ}C$, wild-type, commercial, and recombinant phytases retained $57\%, 32%,\;and\;8\%$ of their original activities, respectively. In conclusion, glycosylation plays a key role in the thermostability of phytase and its enzymatic characterization.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.4
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• pp.256-262
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• 2010

This study evaluated the airborne concentrations of fungi in university laboratories, hospital diagnostic laboratories in Seoul. The incubated fungi was identified by lactophenol cotton blue (LPCB) staining method. Variables such as types of ventilation, temperature and relative humidity were investigated to explain laboratory airborne fungal concentrations. A total of 97 air samples were collected from 10 facilities in two institutions. Aspergilus spp., including Aspergilus niger, Aspergillius flavos and Penicillium spp. were found as predominant species. Airborne fungal concentrations ranged from not detected (ND) to 1,890 CFU/$m^3$. Airborne fungal concentrations were high in general-ventilated facilities and in laboratories where relative humidity ( > 60 %) were high ( p < 0.001). Therefore, we suggest that relative humidity should be maintained to properly reduce the concentration of fungal in university and hospital laboratories.

• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.328-333
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• 2000

The spore of Aspergillus niger KCTC-6144 was immobilized on alginate gel beads. When pumpkin powder was used with glucose for a medium of citric acid fermentation by Aspergillus niger beads, the beaded Aspergilus niger grew up inside the bead and mycelia penetrated through the pore of the bead membrane. The bead size became largely from 2.0∼2.5mm to 6∼8mm after growing at 30$\^{C}$ for 4 days. Studies of optimum culture conditions on citric acid fermentation using Aspergillus niger beads on pumpkin medium (pumpkin powder 1% +glucose 7%, pH 6.0) were carried out in submerged cultures on 250m1 Erlenmeyer flask. As a result, it was found that to reinforce 12% as carbon source was good for citric acid production and that 1% pumpkin powder was good as nitrogen and mineral source in orbital shaker (150rpm) at 30$\^{C}$ for 5 days. The optimum initial pH on citric acid production was pH 6.0 and it was found that 100 beads of immobilized Aspergillus niger was adequate for citric acid production in a 250ml Erlenmeyer flask containing 50m3 of pumpkin medium solution with orbital shaker at 30$\^{C}$ for 5 days. We also found that maximal production of citric acid was 23.5g/ℓ at optimal condition (at 30$\^{C}$ for 5 days, pH 6.0, and 100 beads and medium containing 1% pumpkin powder plus 12% glucose).

• Journal of the Korean Applied Science and Technology
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• v.2 no.2
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• pp.15-20
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• 1985

Influence of vitamins on the felt and lipid production of Aspergilus niger var. macrosporus, Aspergillus fumigatus and penicillium notatum were investigated after 10 days of incubation at $30^{\circ}C$ under static culture condition. The felt of molds were lower in the media containing vitamins than control medium. The lipids produced by each strains were highest yields in media containing vitamins. Among of these Aspergillus niger var. macrosporus and Aspergillus fumigatus produced. 4.6g and 5.28g in medium containing inositol 2.5mg/l and 0.5mg/l, respectively; while Penicillium notatum produced 1.51g in a medium containing thiamine 10mg/l. The major fatty acid of lipids were palmitic acid, stearic acid, oleic acid and linoleic acid. Aspergillus niger var. macrosporus was lower palmitic acid in media containing vitamins than control medium, While linoleic acid was higher in media containing thiamine and inositol. Aspergillus fumigatus was lower oleic acid in media containing vitamins than control medium, While linoleic acid was higher in media containing vitamins. Peniillium notatum was lower palmitic acid, oleic acid and stearic acid in media containing vitamins but linoleic acid was higher. The composition of fatty acid of lipids changed depending on the media containing vitamins but hardly found a certain tendency except linoleic acid which was higher in a media containing thiamines and inositols. The degree of unsaturation of fatty acids in the lipids were comparatively higher in media containing vitamins than control medium.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.206-211
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• 2001

This experiment was conducted to investigate the effects of mixed culture with mycotoxigenic and non-mycotoxigenic fungi on mycotoxin production. For this work, Aspegillus flavus (aflatoxin producing strain), Aspegillus niger (non-mycotoxigenic strain) and Penicillium griseofulvum (patulin producing strain)were cultured in 5 ml SLS medium for 15 days under single or mixed culture. Aflatoxin was determined by direct competitive ELISA, whereas, patulin was measured by HPLC. The mycelial growth, pH and total acidity were also observed by general methods. The mycelial growth was slightly decreased in the mixed culture, meanwhile total acidity was increased and pH was shown lower than that in single culture. Aspergillus flavus produced 145 $\mu\textrm{g}$/ml of aflatoxin for 12 days single culture, but in mixed culture, aflatoxin was decreased to 93%, and was shown as 10.16$\mu\textrm{g}$/ml level. Patulin production in mixed culture was also decreased to 69.3% and was shown only 23.72$\mu\textrm{g}$/ml level as compared with in single culture.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.329-334
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• 2003

To study the interaction between rice weevil and storage molds, the preference of rice weevil to the four mold species (Aspergilus candidus, A. niger, A. flavus and Penicillium spp.) and the resulting reproduction of the rice weevil were observed. The rice weevil preferred rice grains contaminated with the molds to autoclaved ones regardless of the mold species tested. Among the four mold species, A. candidus and Penicillium sp. were highly preferred than the others. Reproduction of the rice weevil was higher on the grains contalminated with A. candidus and Penicillium sp., than on autoclaved ones, but was lower on the grains contaminated with A. flavus. The partial disagreement between preference and reproduction of the rice weevil might be a suggestion that both the weevil behavior adapting nutritional requirements and the process of the long intensive coadaptation of the rice weevil and storage molds requiring similar moisture niche are the major components of the population interaction between the weevil and molds.

• KSBB Journal
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• v.15 no.6
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• pp.600-604
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• 2000

Low density polyethylene(LDPE) film was fabricated with the addition of synthetic ceramic which contained a natural antimicrobial agents. The antimicrobial agents used were isolated from culture broths of methylotropic actinomycetes strains MO-16 and MO-17, and Streptomyces sp. No. 31, which was newly isolated from soils as an antifungal agent. Four-day old culture broth of Streptomyces sp. No. 31 showed strong antifungal activity against Aspergilus niger, a test strain, and retained antimicrobial activity after heat treatment at $121^{\circ}C$ for 15 min. The ceramic LDPE film reduced the growth of total aerobic bacteria in packaged minced pork compared with commercial film. The film revealed a 40 to 50% growth inhibition of E. coli on a contained agar plate. In the storage testing of various packaged foods at room temperature for 30 days, the ceramic LDPE film showed excellent preservation compared with commercial film.