• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.252-255
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• 1999

This study was carried out to investigate the physiological charateristics of Hericium erinaceus in sawdust media. The optimum temperature was $25^{\circ}C$ and the optimum pH was 5. Mycelial growth and density of H. erinaceus was quite good when oak tree sawdust were used as cultural substrates. The best mycelial growth in H. erinaceus were observed when wheat pollard was added as supplement on sawdust substrates. The optimum supplement ratios of wheat pollard and magnecium sulfate were 20% and 0.1% respectively, for H. erinaceus.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1313-1319
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• 2013

This study investigated the effects of low levels of water-soluble pentosans (WSP), alkaline-extractable pentosans (AEP), and xylanase on the growth and organ development of broiler chicks. Three hundred and fifty 1-d-old female broiler chicks were randomly allocated into seven experimental groups of five pen replicates, with ten chicks per replicate. The control group consumed a corn-soybean meal-based diet. Six dietary treatment groups consumed the basal diet supplemented with one of the following: WSP at 50 mg/kg (WSP50) or 100 mg/kg (WSP100); AEP at 50 mg/kg (AEP50) or 100 mg/kg (AEP100); or xylanase at 3 mg/kg (Xase3) or 6 mg/kg (Xase6). Data including the body weight, digestive organ weights, gut length, rectal digesta viscosity, and gut microflora and pH were collected on d 5, 10, and 15. When compared to the control group, WSP50 promoted body weight gain and organ growth throughout the study, calculated as 3-d averages (p<0.05). WSP100 increased weight gain and enhanced organ development (proventriculus, gizzard, and gut) on d 10 (p<0.05), but the 3-d averages were not different from the control group except for the weight of gizzard. Both Xase3 and Xase6 increased the 3-d average weight gain and the growth of the gizzard (p<0.05). WSP50 increased the digesta viscosity compared to Xase3 on d 10 and 15 (p<0.05). WSP50, Xase3, and Xase6 increased the concentration of Lactobacillus in the rectum when compared to the control group (p<0.05), but only Xase3 lowered the digesta pH in the ileum and cecum on d 10 and 15. AEP had minimal influence on the growth and organ development of broilers. The results showed that low levels of WSP, AEP, and xylanase had different effects and underlying mechanisms on the growth and organ development of broiler chicks. WSP50 could increase the growth performance of broilers fed a corn-soybean meal-based diet.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.619-623
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• 1991

To investigate nisin production and resistance of Lactococcus lactis ssp. tactis ML (L. lactis $ML_8$, effects of medium, pH of culture broth, and cell growth on the nisin activity, and effect of nisin with or without $Ca^[2+}$ ion on the growth of L. lactzs were analyzed. In the bio-assay of nisin by the agar diffusion method, inhibition-zone diameter of Micrococcus Javus was propotional to the logarithm of nisin concentration ranged 0.5~20 unitlml (12.5~500 ng/mf). Nisin activity of the pasteurized culture filtrates of L. lactis MLs was high at pH 2!3 but was inactivated completely at pH over 6.0. Nisin production of the L. lactis $ML_8$ cultured on LTB broth increased at late logarithmic phase and reached 10.5 unitlml after 16 hr. The cell growth of L. lactis LM 0230, a plasmid free and nisin sensitive strain, was inhibited on agar medium containing 7 unitlrnl of nisin, while L. lactis $ML_8$ showed high survival ability at 20 unitld of nisin. When 40 mM $Ca^[2+}$ ion was added to Elliker broth with 8 unitlml of nisin, the growth pattern of L. lactis $ML_8$ was similiar to that on control medium which did not contain nisin and $Ca^[2+}$ ion, and this suggested that $Ca^[2+}$ increased the nisin resistance of the L. lactis.

• Journal of Environmental Science International
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• v.20 no.9
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• pp.1183-1190
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• 2011

This study was aimed to establish the evaluating protocol and standard assessment for genetically modified (GM) hot pepper and to find out a proper statistic method to analyze for equality of agricultural characters between GM and non-GM pepper lines. GM and non-GM hot pepper lines were cultivated in two GMO fields in the middle region of Korea and total of 52 agricultural characters were collected during the plant growing season for 4 years, 2007 to 2010. Levene's test was conducted to confirm the homogeneity of raw data before statistic analysis. Two-way ANOVA in the multivariate tests and t-test were conducted to analyze 52 agricultural characters in order to find out the equality between H15 and P2377. From the statistical analysis through two-way ANOVA, 16 out of 16 plant growth traits, 9 out of 18 green fruit traits and 7 out of 18 red fruit traits among 4 years and 9 out of 16 plant growth traits, 4 out of 18 green fruit traits and 3 out of 18 red fruit traits between H15 and P2377 have shown the statistic differences. With the same raw data of 52 agricultural characters, t-test was also conducted. Based on the result from t-test, only 1 out of 16 plant growth traits, 2 out of 18 green fruit traits and 1 out of 18 red fruit traits have shown the differences between H15 and P2377, so that it was concluded that there is no statistic difference between H15 and P2377 in terms of agricultural characters. Also, the t-test is a proper statistic method to analyze each trait between GM and its control lines in order to evaluate agricultural characters.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.146-152
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• 2005

For the application of ectomycorrhizal seedlings on damaged slope lands, studies on cultural characteristics of Lyophyllum shimeji and ectomycorrhizal associations of Lespedeza cyrtobotrya seedlings were carried out by artificial inoculation of L. shimeji. Mycelial growth of L. shimeji was best on MP (1% malt extract, 0.1% peptone, 1% glucose and 1.5% agar) medium. An optimum temperature and pH for the mycelial growth were $25^{\circ}C$ and pH6, respectively. Mycorrhizal root of L. cyrtobotrya seedlings inoculated with L. shimeji showed characteristics of ectomycorrhizas with Hartig net. Growth rate of the mycorrhizal seedlings's roots was higher than that of non-mycorrhizal seedlings. When the mycorrhizal seedlings were transplanted in slope land, survival rate and dry weight were 62% and 850 mg/seedling, respectively. On the other hand, survival rate and dry weight of non-mycorrhizal seedlings were 11% and 430 mg/seedling, respectively.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.371-376
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• 1985

We investigated the growth parameters of Candida parapsilosis isolated from spoiled red ginseng extract. The optimum pH range for C. parapsilosis was 6.0, whereas the minimum and maximum pH values that permitted growth were 3.0 and 11.0, respectively. For cells grown in PG medium plus 0 and 60％ sucrose, the optimum water activity(Aw) values were 0.98 and 0.97, respectively. The optimum temperature for C. parapsilosis were 3$0^{\circ}C$ at an Aw of 0.90 in 4.8％ potato dextrose broth with 18％ sucrose (PGS). Cations inhibiting the growth of C parapsilosis were L $i^{+}$ $Ca^{2+}$, $Mg^{+2}$, $K^{+}$ in decreasing order, while anions were S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ , C $l^{[-10]}$ .TEX> .

• Journal of Life Science
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• v.9 no.1
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• pp.8-14
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• 1999

The growth rate of the A252 strain was increased in tryptic soy broth (TSB) and malt extract-yeast extract medium (ISP-2), but the antifungal activity of culture filtrate was efficient in the media of TSB and nutrient broth. The mycelial growth and the antifungal activity of culture filtrate in TSB medium were optimized at $25^{\circ}C$ and pH 6.5. The growth in 2$\%$TSB concentration was more effective than 1$\%$, but there was no difference of the antifungal activity by the TSB concentrations. The mycelial growth of A252 strain reached to maximum at 72 hr after inoculation, whereas the antifungal activity of culture filtrate was shown to have the highest level at idiophase (60 hr) after inoculation and was decreased a little after 96 hr incubation. The antifungal activity was stable in the pH range of 4 to 11 and evenly at $121^{\circ}C$. The A252 strain was characterized as Streptomyces species by the physiological properties and examination of sporophore me morphology.

• Journal of Soil and Groundwater Environment
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• v.20 no.4
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• pp.113-121
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• 2015

The contaminated soil at abandoned smelter areas present challenge for remediation, as the degraded materials are typically deficient in nutrients, and rich in toxic heavy metals and metalloids. Bioremediation technique is to isolate new strains of microorganisms and develop successful protocols for reducing metal toxicity with heavy metal tolerant species. The present study collected metal contaminated soil and characterized for pH and EC values, and heavy metal contents. The pH value was 5.80, representing slightly acidic soil, and EC value was 13.47 mS/m. ICP-AES analytical results showed that the collected soil samples were highly contaminated with various heavy metals and metalloids such as lead (183.0 mg/kg), copper (98.6 mg/kg), zinc (91.6 mg/kg), and arsenic (48.1 mg/kg), respectively. In this study, a bacterial strain, Bacillus cereus KM-15, capable of adsorbing the heavy metals was isolated from the contaminated soils by selective enrichment and characterized to apply for the bioremediation. The effects of heavy metal on the growth of the Bacillus cereus KM-15 was determined in liquid cultures. The results showed that 100 mg/L arsenic, lead, and zinc did not affect the growth of KM-15, while the bacterial growth was strongly inhibited by copper at the same concentration. Further, the ability of the bacteria to adsorb heavy metals was evaluated.

• Journal of Microbiology
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• v.34 no.2
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• pp.144-150
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• 1996

During growth of the genetically engineered E. coli CU103 in different media, extracellular DNAs released from the cells were studied. The extracellular DNAs released in the medium were concentrated by an thanol precipitation method and then quantified by a fluorescence method using Hoechst 33258. The released extracellular DNAs were also examined by gel electrophoresis and identified by Southern hybridization for the cloned pcbCD genes. The chromosomal DNAs and recombinant plasmid containing the cloned genes were observed to be released in an exponential growth phase. In Luria-Bertani (LB) broth and MM2-GLUCOSE, 210 and 69 ng/ml of DNAs were detected, respectively, after 3-4 days incubation at $30^{\circ}C$ and at pH 7.0. But the released DNAs were measured to be about 10-15 ng/ml in filtered river water (FW) and Tris-EDTA (TE). The at both $15^{\circ}C$ and $4^{\circ}C$, but the released DNAs were more easily degraded at the higher temperature. The extracellular DNAs were produced about 2 times more at pH 7.0 than at both pH 5.0 and pH 9.0 in MM2-glucose medium at $30^{\circ}C$. Therefore, the extracellular DNAs were found to be released actively from the cells during growth in liquid media.

• Korean Journal of Environmental Agriculture
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• v.18 no.3
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• pp.245-249
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• 1999

This study was carried out to investigate the influence of artificial acid rain on the growth of soybean irradiated with the low dose gamma radiation. The growth patterns of Hwangkumkong and Bangsakong were not dependent on the acid rain treatment and the period of seed storage but the radiation dose. In Hwangkumkong, the optimal irradiation dose for the growth promotion was lower in the acid rain treatment group than the control group. The symptom of acid rain damage appeared broadly around pH 2.20, were higher in Hwangkumkong than in Bangsakong, and were more effective in the seeds of 1997 than 1995. But the damage symptom of Bangsakong was not dependent on the acid rain treatment and the irradiation of gamma radiaiton.