• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1077-1086
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• 2001

The sprA and sprB gene encoding chymotrypsin-like proteases Streptomyces griseus protease A (SGPA) and Streptomyces griseus protease B (SGPB) and the sprT gene that encodes Streptomyces griseus trypsin (SGT) were cloned from Streptomyces griseus ATCC10137 and overexpressed in Streptomyces lividans TK24 as a heterologous host. The chymotrypsin activity of tole culture broth measured with the artificial chromogenic substrate , N-succinyl-ala-ala-pro-phe-p-nitroanilide, was 10, 14 and 14 units/mg in the transformants haboring the sprA, sprB and sprD genes, respectively. The growth of S. lividans reached the maximum cell mass after 4 days of culture, yet SGPA and SGPD production started in the stationary phase of cell growth and kept increasing for up to 10 days of culture in an R2YE medium. The trypsin activity of the culture broth measured with the artificial chromogenic substrate , N-${\alpha}$-benzoyl-DL- arginine-p-nitroanilide , was 16 units/mg and SGT production started in the stationary phase of cell growth and kept increasing for up to 10 days of culture in an R2YE medium. The introduction of the sprA gene into S, lividans TK24 triggered the biosynthesis of pigmented antibiotics, actinorhodin and undecylprodigiosin, and induced significant morphological changes in the colonies in Benedict, R2YE, and R1R2 media. In addition, the introduction of the sprT gene also induced morphological changes in the colony shape without affecting the antibiotic production, thereby implying that certain proteases would appear to play very important and specific roles in secondary-metabolites formation and morphological differentiation in Streptomyces.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.393-406
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• 1993

Antibacterial substances produced by Lactobacillus casei subsp. and Streptococcus faecium were examined for its antibacterial effects against some pathogenic bacteria. They were partially purified with ammonium sulfate precipitation, methanol-acetone extraction, G-50 gel filtration and examined its characteristics. When L casei subsp. and Str faecium were cultivated in MRS broth, stationary phase of L casei is until 24 hours and Str faecium is 20 hours. pH change of the cultured medium was both decreased after 12 hours and then constant at pH 4.5~4.6 after 28 hours. MRS broth culture fluids of L casei subsp. and Str faecium appeared the antibacterial effects by the spot-on-the-lawn method against ETEC, Sal pullorum and Sta aureus. Culture filtrates of L casei subsp. and Str faecium also appeared the antibacterial effects by the disc diffusion method. Culture filtrates of L casei sub. rhamnosus 7469 produced 0.032M of lactic acid and 0.01M of acetic acid. Str faecium 27273 also produced 0.027M of lactic acid and 0.01M of acetic acid. Protein concentrations of culture filtrates produced by L casei sub rhamnosus 7469 and Str faecium 27273 was $495{\mu}g/m{\ell}$ and $594{\mu}g/m{\ell}$, respectively. Antibacterial substances which are partially purified by ammonum sulfate precipitation, methanol-acetone extraction and G-50 gel filtration inhibit the growth of ETEC, Sal pullorum and Sta aureus. Characteristics of purified antibacterial substances was examined. Its molecular weight was about 31Kd, stabilized at $100^{\circ}C/20min.$ and some of proteolytic enzyme treatment.

• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.159-164
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• 1994

Myceliuml growth and spore formation of Streptomyces albidoflavus SMF301 in submerged culture were compared with the metabolism of cysteine. Cysteine added to the culture was metabolized by cysteine desulfhydrase (EC 4.4.1.1.) to produce ammonium ions, hydrogen sulfide, and pyruvate. The redox potential of the culture broth was lowered immediately as the result of the metabolism of cysteine, which caused a lag period of mycelium growth. However enhanced activities of pyruvate dehydrogenase and a-ketoglutarate dehydrogenase were confirmed in the culture containing cysteine, indicating that pyruvate was utilized to support further mycelium growth.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.266-269
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• 2006

For the purpose of application for biomass of Tricholoma matsutake, the optimum culture condition were determined. It was found that the optimum culture condition for spot culture of Tricholoma matsutake were pH 5.5 and 3% brown rice meal at $24^{\circ}C$ for 35 days with MMN medium. And the optimum culture condition of bioreactor for biomass were $18^{\circ}C$ and 60 days with PDMP broth.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.57-60
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• 1993

The herbicidal compound, 3D5 was isolated from the culture broth of strain 3D5, a soil isolate. Based on taxonomic studies, this culture was identified as Streptomyces sp. 3D5.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.32-37
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• 1986

In fermentation studies it revealed that Streptomyces sp. SMF 3001 started to synthesize extracellular alkaline protease from early exponential phase of cell growth. The biosynthesis of the alkaline protease was greatly induced by skim milk as a sola nitrogen source and further stimulation was observed under inorganic sulphur limited culture. However, it was found that the biosynthesis was apparently repressed by $NH_4^+$ and free amino acids, specially by cysteine. It was considered that the strain SMF 301 of Streptomyces sp. would produce the alkaline protease for the uptake of sulphur compounds from protein contained in the culture broth.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.21-27
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• 1978

The growing behavior of Candida albicans in various concentration of glucose and corticosteroid media was studied with the method of modified hanging slide culture. The strains of Candida albicans used in this study were obtained from vaginal swab from outpatients and were isolated from cultured colonies on Sabouraud's glucose agar media. To detect the budding rate of blastospore, the diluted suspension of Candida albicans in normal saline were inoculated into various concentration of glucose (Gl, G2, G3, G4), corticosteroid (S1, S2, S3, S4) and corticosteroid with 10% pepton broth (D1, D2, D3, D4) respectively and cultured at room temperature $(22{\sim}25^{\circ}C)$. The number of budding of blastospore were counted under the high power field of light microscope (400X) at specific time interval, e.g, 1, 2, 3, 6, 9, 12, 18, and 24 hours after inoculation. The results are as following: 1. The most effective budding rate was seen in G4 media (1.25% glucose) in 18 hours aft inoculation (89%). 2. The budding rate in Sabouraud's glucose broth with various concentration of dexamethasone added, was not significantly different from that of simple Sabouraud's glucose broth within 18 hours after inoculation, but there was statistically. significant difference in two budding rate at 24 hours observation. 3. The budding rate in 10% pepton broth media with various concentration of dexamethasone was almost same budding rate in control group, which is normal saline and 10% pepton broth, except on 2 and 24 hours results.

• Journal of Life Science
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• v.22 no.6
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• pp.823-827
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• 2012

A bacterial strain producing a fibrinolytic enzyme, subtilisin CP-1, was isolated from Doen-Jang, a Korean traditional fermentation food. Based on the analysis of gene sequence of 16S rRNA and biochemical analysis, the strain was identified as Bacillus sp. and named as Bacillus sp. CP-1. To investigate the effect of the medium on the production of fibrinolytic enzyme from Bacillus sp. CP-1, two commercial bacterial culture media, tryptic soy broth (TSB) and Luria-Bertani (LB), were applied to the cultivation of Bacillus sp. CP-1. The strain secreted only one proteolytic enzyme (subtilisin CP-1) in the culture broth. The molecular weight of subtilisin CP-1 was estimated to be 28 kDa. Subtilisin CP-1 was optimally active at pH 9.0 and $45^{\circ}C$, and exhibited high specificity for Meo-Suc-Arg-Pro-Tyr-pNA (S-2586), a synthetic chromogenic substrate for chymotrypsin. The first eight amino acid residues of the N-terminal sequence of the enzyme are AQSVPYGI; this sequence is identical to that of subtilisin NAT and E.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.152-158
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• 2016

The cause of death was investigated with several dead cabbage moth larvae in breeding box. Bacterial strains were isolated and selected from the dead larvae by bioassay. One of them was identified as Serratia marcescens used by morphological characteristics and gene sequencing. S. marcescens were cultured by Luria Bertani (LB) media broth for bioassay. When 100-fold dilution of culture broth to third larvae of diamondback moth, Plutella xylostella, it was showed a 100% mortality at 2 days after treatment, and only 10-fold dilution of supernatant liquid was showed 86.6% mortality. When the culture broth of S. marcescens was applied to the larvae of beet armyworm, Spodoptera exigua, contact and feeding toxicity were 20 and 8% of mortality, respectively. Otherwise, when the culture broth of S. marcescens was applied to 5 major plant pathogens, antibacterial activities against Fusarium oxysporum, Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici and Sclerotinias clerotiorum were 4.7, 11.3, 20, 15.7 and 42.6%, respectively. Also, degradation ability of S. marcescens against protein and chitin were examined.

• Journal of Life Science
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• v.31 no.7
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• pp.654-661
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• 2021

In this study, in order to isolate excellent whitening agents from fungal cultural broth, various fungi were collected from wild areas in South Korea and then screened for tyrosinase inhibition activity, as tyrosinase is a precursor for the biosynthesis of melanin in regulating skin color. A fungus strain that inhibits tyrosinase activity has been identified and confirmed as Trichoderma viridescens (later renamed T. viridescens SW-1) via ITS sequencing. In T. viridescens SW-1, tyrosinase inhibitory activity was strongest on day three of culture. A 5% culture broth showed a tyrosinase inhibitory activity greater than 90% and exhibited high thermostability on day three. At 10% culture broth, the accumulations of intra- and extracellular melanin were inhibited above 27.1% and 7.5%, respectively. In summary, the physical and functional properties of the tyrosinase inhibitory substances of T. viridescens SW-1 included high levels of inhibition of melanin synthesis and antioxidative activity as well as thermostability. Therefore, we suggest that the whitening substance identified from the cultural broth of T. viridescens SW-1 has potential for application as a functional cosmetic ingredient.