• Journal of Life Science
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• v.14 no.1
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• pp.51-56
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• 2004

The polysaccharide isolated from Phellinus species has been known as a folk remedy, including antitumor and immune-stimulating activities. However, there are lacks of knowledge about mycelial growth and exopolysaccharide (EH) production in its submerged culture. We investigated the optimal conditions on mycelial growth and EPS production in Phellinus baumii. The optimal temperature and initial pH for mycelial growth and EPS production in shake flask culture of P. baumii were proved to be 3$0^{\circ}C$ and pH 5.0, respectively. In case of carbon source, cellobiose and maltose were highly efficient for mycelial growth and fructose and mannitol were also relatively favorable for EPS production. Yeast extract was the most suitable nitrogen source for mycelial growth and EPS production. The composition of optimal culture medium was determined to be fructose 20 g/L, yeast extract 20 g/L, and $CaCl_2$ 0.55 g/L, respectively. Under the optimal culture condition, the maximum mycelial biomass and EPS achieved in a 5-L stirred-tank fermenter were 17.43 g/L and 3.6 g/L, respectively. It was found that the EPS was a glycoprotein onsisted of mainly arginine (14.1%) and glycine (12.0 %) in protein moiety and mainly mannose (48.7%) and arabinose (38.4%) in carbohydrate moiety.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.339-345
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• 2009

Two lactic acid bacteria (LAB) with high ornithine-producing capacity were isolated from kimchi. Examination of the biochemical features using an API kit indicated that the strains belonged to the members of Weissella genus. They were gram positive, short rod-type bacteria, and able to grow anaerobically with $CO_2$ production. The isolates grew well on MRS broth at $25\sim37^{\circ}C$ and pH of 6.0~7.0. The optimum temperature and pH for growth are $30^{\circ}C$ and pH 6.5. The isolates fermented arabinose, ribose, xylose, glucose but not cellobiose, galactose, raffinose, or trehalsoe. The 16S rDNA sequences of isolates showed 99.6% and 99.7% homology with the Weissella koreensis S5623 16S rDNA (access no. AY035891). They were accordingly identified and named as Weissella koreensis OK1-4 and Weissella koreensis OK1-6, and could produce ornithine from MRS broth supplemented with 1% of arginine at a productivity of 27.01 and 31.41 mg/L/h, respectively. This is the first report on the production of ornithine by the genus Weissella isolated from kimchi.

• Food Science and Preservation
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• v.14 no.2
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• pp.194-200
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• 2007

In order to enhance the functionality and storage period of traditional fermented foods, the strain CH-14, which To enhance the quality of traditional fermented foods, and to lengthen acceptable storage periods, a bacterial strain, CH-14, showing potent enzyme activities and antibacterial capabilities, was isolated and characterize4 The bacterium wn Gram-positive, catalase-positive, oxidase-negative, formed endospores, expressed flagella, was rod-shaped, and had dimensions of 0.5 0.7m and 3.5 4.2m. The bacterium CH-14 was identified as Bacillus subtilis using Bergey's Manual of Systematic Bacteriology, Bergey's Manual of Determinative Bacteriology, and an API 50 CHL Carbohydrate Test Kit. An optimum growth medium contained 2% (w/v) cellobiose as a carbon source, a mixture of 0.5% (w/v) yeast extract and 0.5% (w/v) peptone as nitrogen sources, and 0.05% (w/v) $MgSO_4{\cdot}7H_2O$. The optimal culture temperature and the optimal initial pH were in the ranges of 30 $45^{\circ}C$ and 4.5 10.0, respectively. Maximum production of the antibacterial substance occurred after 24h of culture. The minimum inhibitory concentrations of the antibacterial substance were 5mg bacterial dry weight/mL against E. coli and P. mirabilis, and 10 mg/mL against S. aureus, S. enteritidis and V. parahaemolyticus.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.106-111
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• 2003

A novel carbohydrolase, which is a DXAMase, containing both dextranase and amylase equivalent activities, was purified from Lipomyces starkeyi KSM22. The purified DXAMase was also found to hydrolyze cellobiose, gentiobiose, trehalose and melezitose, while disproportionation reactions were exhibited with various di- and tri-saccharides, such as maltose, isomaltose, gentiobiose, kojibiose, sophorose, panose, maltotriose, and isomaltotriose with various kinds of oligosaccharides produced as acceptor reaction products. Furthermore, the purified DXAMase hydrolyzed raw waxy rice Starch and produced maltodextrin to the extent of 50% as a glucose equivalent.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.255-259
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• 1996

$\beta$-Glucosidase was known to be involved in the mutagenic activation of $\beta$-glucosides. The level of $\beta$-glucosidase in the feces of adults was 2.7 times higher than that of infants. There was no difference in the percentage of $\beta$-glucosidase positive strains among Bifidobacterium isolates between adults and infants, corresponding to 90 and 92$%$, respectively. However, the strains from adults showed 1.9 times higher enzyme activity than those from infants when grown in Brain Heart Infusion medium. $\beta$-Glucosidase negative strains could not ferment $\beta$-glucosidase substrates, such as cellobiose, salicin, naringin, esculin and arbutin. Presence of $\beta$-glucosidase in Bifidobacterium did not alter the degree of growth in reconstituted skim milk. The $\beta$-glucosidase level was much lower in milk and vegetable medium, although cells grew above $10^8$cfu/ml, than in BHI medium. This study suggests that metabolic activation of the $\beta$-glucosides by Bifidobacterium $\beta$-glucosidase varies significantly depending on types of growth medium.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.511-517
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• 1992

Ethanol was utilized by mixed rumen microbes, but addition of pentachlorophenol (25 mg/l), a methanogen inhibitor, suppressed the utilization of ethanol. Carbon monoxide (50% of the gas phase), a hydrogenase inhibitor, more strongly suppressed the utilization of ethanol, propanol, and butanol. These results suggest that the major ethanol utilizers are $H_2$ producers. Ethanol utilization was depressed at low pH (below 6.0). Since methanogens were shown to be relatively resistant to low pH, it appears that ethanol utilizers are particularly sensitive to low pH. Ruminococcus albus and R. flavefaciens in mono-culture produced ethanol from carbohydrate (glucose and cellobiose), even when a high level (170 mM) of ethanol was present. Ethanol was not utilized even in the absence of carbohydrate, but the co-culture of these bacteria with methanogens resulted in the utilization of ethanol, i.e., when $H_2$ was rapidly converted to $CH_4$, R. albus and R. flavefaciens utilized ethanol. These results suggest that ethanol is utilized when the electrons liberated by the oxidation of ethanol are rapidly removed, and ready electron disposal in ethanol-utilizing, $H_2$-producing bacteria is accomplished by the interspecies transfer of $H_2$.

• Journal of Environmental Health Sciences
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• v.22 no.2
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• pp.10-18
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• 1996

Experiments were carried out to find the possibility of an economic production of single cell protein(SCP) in mixed culture by Cellulomonas sp. KL-6 and a second organism. The second organism, strain LI-10, was isolated from the large intestines of a mouse. 1. When these strains were mixed, cell growth and carboxymethyl cellulase (CMCase) activity were increased to about 63% and 161%, respectively compared with that of single culture of strain KL-6. We found the mixed culture as a proper method of degradation of cellulose in our study. 2. Strain LI-10 was identified as E. coli. 3. This strain produced trace amounts of cellobiose, but glucose was not found in detectable amounts in the filter paper(FP) medium. 4. $CaCO_3$ injected in the medium at the ratio of 0.1% not only enhanced cell growth but also was effective as an acid neutralizing agent. 5. When this organism was cultured under the optimal medium (glucose 0.1%, $NH_4Cl$ 0.1%, yeast extract 2.0%, $KH_2PO_4$ 0.1%, KCl 0.05%, pH 7.2 and a temperature 30$\circ$C) for 5 days, a cell mass produced 1.18 g/l. The results showed the increase of cell mass up to 300% compared to 0.28 g/l produced in CMC medium.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.164-170
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• 2008

Carbon utilization by Chryseobacterium strain KJ1R5 was studied to enhance its biocontrol activity against Phytophthora capsid. Chryseobacterium strain KJ1R5 has previously been shown to control Phytophthora blight of pepper (Capsicum annuum L.). Strain KJ1R5 could utilize carbon sources such as L-arabinose, D-cellobiose, ${\beta}-lactose$ and D-galactose well. P. capsici could utilize D-glucose well, showing the absorbencies ranged from 0.577 to 0.767 at 600nm. When 2% L-arabinose, which could only be utilized by the bio-control strain KJ1R5, was amended into the bacterial suspension, the efficacy of biological control increased. Among the amendments of various carbon sources into bacterial suspension, L-arabinose and D-(+)-glucose significantly enhanced biological control activity, resulting in a reduction of disease incidence to 6.9%, compared to 21.9% for the strain KJ1R5 alone and 81.3% for P. capsici inoculation alone, indicating that amendment with specific carbon sources could increase the biological control activity.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.65-68
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• 2001

${\alpha}$-L-Arabinofuranosidase was purified from the culture supernatant of Bacillus sp. DSNC 101. The enzyme had a molecular weight of 56 kDa. Optimum temperature and pH for ${\alpha}$-L-arabinofuranosidase activity were 55$^{\circ}C$ and 7.0 respectively. The Michaelis constant(Km) and maximal reaction velo-city(Vmax) for p-nitrophenyl-${\alpha}$-L-arabinofuranoside were 1.0 mM and 113.6 U/mg protein, respe-ctively. ${\alpha}$-L-Arabinofuranosidase was completely inhibited by HgCl$_2$ and CuSO$_4$. The enzyme was spe-cific for the ${\alpha}$-linked arabinoside in the furanoside configuration. The enzyme was produced during growth on agricultural residue such as rice straw, but not during growth on spelt xylan, glucose or cellobiose.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.579-587
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• 2018

For biotechnological production of high-valued ${\beta}-{\text\tiny{D}}$-hexyl glucoside, the catalytic properties of Hanseniaspora thailandica BC9 ${\beta}$-glucosidase purified from the periplasmic fraction were studied, and the transglycosylation activity for the production of ${\beta}-{\text\tiny{D}}$-hexyl glucoside was optimized. The constitutive BC9 ${\beta}$-glucosidase exhibited maximum specific activity at pH 6.0 and $40^{\circ}C$, and the activity of BC9 ${\beta}$-glucosidase was not significantly inhibited by various metal ions. BC9 ${\beta}$-glucosidase did not show a significant activity of cellobiose hydrolysis, but the activity was rather enhanced in the presence of sucrose and medium-chain alcohols. BC9 ${\beta}$-glucosidase exhibited enhanced production of ${\beta}-{\text\tiny{D}}$-hexyl glucoside in the presence of DMSO, and 62% of ${\beta}-{\text\tiny{D}}$-hexyl glucoside conversion was recorded in 4 h in the presence of 5% 1-hexanol and 15% DMSO.