• Food Science and Biotechnology
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• 제16권5호
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• pp.843-847
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• 2007

Strain NK34 was characterized for probiotic use. Strain NK34 was named Lactococcus lactis NK34 based on API 50 CHL kit results and 16S rDNA sequencing. L. lactis NK34 was highly resistant to artificial gastric juice (pH 2.5) and artificial bile acid. Based on results from the API ZYM kit, 4 enzymes were produced. L. lactis NK34 was resistant to all antibiotics tested except for $10\;{\mu}g/mL$ roxithromycin and $10\;{\mu}g/mL$ erythromycin. The cholesterol-lowering effect of L. lactis NK34 was about 46.9%. Concentrations of interleukin $(IL)-1{\alpha}$ in the $20{\times}$ concentrated supernatant of L. lactis NK34 was about 361 pg/mL. L. lactis NK34 was also found to inhibit the growth of colon cancer cells due to MNNG-induced DNA damage. These results demonstrate the potential of L. lactis NK34 as a health-promoting probiotic.

• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.773-788
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• 2003

Ostrich farming is a developing industry in most countries in the world, with farm profitability being largely dependent on the quality of the products, especially skins and meat. To produce quality products, it is essential to ensure that nutrient supply matches the nutrient requirements of ostriches during their growth. To achieve this, information on feed utilisation efficiency and nutrient requirements of ostriches at different maturity stages is required. In South Africa, a number of experiments were carried out to assess the nutritive value of feed and to define the nutrient requirement of ostriches. These data were derived from limited number of birds and the direct application of the results to ostrich farming in Australia and other countries is questionable due to the difference in environment and feed resources. Initially ostrich farmers used data from poultry as a guideline for feed formulation, but in recent years more data has become available for ostriches. Ostriches have a better feed utilisation efficiency and a larger capacity of using high fibre feeds such as pastures than poultry. This review revealed that there are a number of areas there further nutritional research and development is required to ensure the ostriches are provided suitable diets to maximise farm profitability. These include the assessment of the nutritive value of feed ingredients for ostrich chicks and adult birds, the determination of nutrient requirements of ostriches under different farming systems, the development of ostrich diet for producing specific product, and grazing management strategies of ostriches in a crop-pasture rotation system.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.756-764
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• 2014

Apoptin, a chicken anemia virus-encoded protein, induces apoptosis in chicken or human tumor cells, localizing in their nuclei as opposed to the cytoplasm of non-transformed cells. The present study was undertaken to investigate whether ABPs1 could potentiate apoptin-induced apoptosis in HeLa cells. ABPs1 and the apoptin genes were successfully cloned into pIRES2-EGFP expression vector and expressed in HeLa cells. We report that ABPs1 augments apoptin cell growth inhibition in a concentration- and time-dependent manner. The DAPI staining and scanning electron microscopy observations revealed apoptotic bodies and plasma membrane pores, which were attributed to apoptin and ABPs1, respectively. Further, ABPs1 in combination with apoptin was found to increase the expression of Bax and to decrease the expression of survivin compared with either agent alone or the control. The apoptotic rate of HeLa cells treated with ABPs1 and apoptin in combination for 48 h was 53.95%. The two-gene combination increased the caspase-3 activity of HeLa cells. Taken together, our study suggests that ABPs1 combined with apoptin significantly inhibits HeLa cell proliferation, and induces cell apoptosis through membrane defects, up-regulation of Bax expression, down-regulation of survivin expression, and activation of the caspase-3 pathway. Thus, the combination of ABPs1 and apoptin could serve as a means to develop novel gene therapeutic agents against human cervical cancer.

• 한국농공학회지
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• 제43권2호
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• pp.94-104
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• 2001

A pilot study was performed at the experimental field of Konkuk University in Seoul, to examine the feasibility of the constructed wetland system for sewage and the effect of treated sewage irrigation on the paddy rice culture and its soil characteristics. The constructed wetland performed well, in that effluent concentrations of pollutants were significantly lower than concentrations of the influent. Median removal efficiencies of BOD$_{5}$ was about 78% and slightly lower during winter. Removal efficiencies form TN and TP were approximately 48 and 21%, respectively, and relatively less effective than that of BOD$_{5}$. Irrigation of treated sewage to paddy rice culture did not affect adversely in both growth and yield of rice. Instead, plots of treated sewage irrigation showed up to 50% more yield in average than the control plot. It implies that treated sewage irrigation might be beneficial to rice culture rather than detrimental as long as it is treated adequately and used properly. Soil was sampled and analyzed before transplanting and after harvesting. pH was slightly increased due to irrigation water, but it may not be concerned as long as the treated sewage is within the normal range. EC was increased in first year but decreased in second year, therefore salts accumulation in the soil could be less concerned. OM and CES was slightly increased, which might be beneficial on growing plants. TN did not show apparent pattern. Available phosphorus was decreased after rice culture, but the quantity of phosphorus(TP-available phosphorus) was rather increased which implies that excessive phosphorus supply may result in phosphorus accumulation in the soil. Overall, the constructed wetland was thought to be an effective sewage treatment alternative, and treated sewage could be reused as a supplemental source of irrigation water for paddy rice culture without causing adverse effect as long as it is treated adequately and used properly. For full-scale application, further investigation should be followed on environmental risk assessment, tolerable water quality, and fraction of supplemental irrigation.ion.

• Asian-Australasian Journal of Animal Sciences
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• 제21권2호
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• pp.225-231
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• 2008

Oxidative stress plays a crucial role in the laying stage which is a critical period for chick survival. We investigated the relationship of neonatal chick performance, brain antioxidant status and vitamin E supplementation level in hens. Starting at 17 weeks, hens were randomly divided into five groups. The control group received a basal diet without supplemental vitamin E (VE, dl-${\alpha}$-tocopherol acetate). Other groups received the same basal diet supplemented with vitamin E (40, 80, 120 and 160 mg/kg) through growth to egg production. Hens were artificially inseminated at 28 weeks of age and egg yolks were collected at day two. All remaining eggs were hatched. Yolk vitamin E content, hatchability and fertility of eggs were evaluated. Brains of the newly hatched chicks were further evaluated for their oxidative stress status, antioxidative status and vitamin E levels. Increased reproductive performance was observed in fertility and hatchability in the group supplemented at 40 mg/kg. Egg yolk and neonatal brain ${\alpha}$-tocopherol was highest in eggs from hens fed 120 mg/kg and 80 mg/kg supplemental vitamin E, respectively. Brain MDA, ROS and iron levels were significantly higher in unsupplemented hens (p<0.01). SOD activity was significantly higher in the group supplemented at 160 mg/kg than in all other groups. We concluded that maternal supplementation of vitamin E had beneficial effects on fertility, hatchability of eggs, neonatal brain oxidative status and SOD activity.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2533-2539
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• 2012

Annona muricata L (Annonaceae), commonly known as soursop has a long, rich history in herbal medicine with a lengthy recorded indigenous use. It had also been found to be a promising new anti-tumor agent in numerous in vitro studies. The present investigation concerns chemopreventive effects in a two-stage model of skin papillomagenesis. Chemopreventive effects of an ethanolic extract of A. muricata leaves (AMLE) was evaluated in 6-7 week old ICR mice given a single topical application of 7,12-dimethylbenza(${\alpha}$)anthracene (DMBA 100ug/100ul acetone) and promotion by repeated application of croton oil (1% in acetone/twice a week) for 10 weeks. Morphological tumor incidence, burden and volume were measured, with histological evaluation of skin tissue. Topical application of AMLE at 30, 100 and 300mg/kg significantly reduced DMBA/croton oil induced mice skin papillomagenesis in (i) peri-initiation protocol (AMLE from 7 days prior to 7 days after DMBA), (ii) promotion protocol (AMLE 30 minutes after croton oil), or (iii) both peri-initiation and promotion protocol (AMLE 7 days prior to 7 day after DMBA and AMLE 30 minutes after croton oil throughout the experimental period), in a dose dependent manner (p<0.05) as compared to carcinogen-treated control. Furthermore, the average latent period was significantly increased in theAMLE-treated group. Interestingly, At 100 and 300 mg/kg, AMLE completely inhibited the tumor development in all stages. Histopathological study revealed that tumor growth from the AMLE-treated groups showed only slight hyperplasia and absence of keratin pearls and rete ridges. The results, thus suggest that the A.muricata leaves extract was able to suppress tumor initiation as well as tumor promotion even at lower dosage.

• Journal of Microbiology and Biotechnology
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• 제26권3호
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• pp.540-548
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• 2016

Microbially induced calcium carbonate precipitation (CCP) is a long-standing but re-emerging environmental engineering process for production of self-healing concrete, bioremediation, and long-term storage of CO₂. CCP-capable bacteria, two Bacillus strains (JH3 and JH7) and one Sporosarcina strain (HYO08), were isolated from two samples of concrete and characterized phylogenetically. Calcium carbonate crystals precipitated by the three strains were morphologically distinct according to field emission scanning electron microscopy. Energy dispersive X-ray spectrometry mapping confirmed biomineralization via extracellular calcium carbonate production. The three strains differed in their physiological characteristics: growth at alkali pH and high NaCl concentrations, and urease activity. Sporosarcina sp. HYO08 and Bacillus sp. JH7 were more alkali- and halotolerant, respectively. Analysis of the community from the same concrete samples using barcoded pyrosequencing revealed that the relative abundance of Bacillus and Sporosarcina species was low, which indicated low culturability of other dominant bacteria. This study suggests that calcium carbonate crystals with different properties can be produced by various CCP-capable strains, and other novel isolates await discovery.

• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2058-2071
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• 2015

A comparative study was conducted to evaluate precision and accuracy in controlling the temperature dependence of encapsulated microbial time-temperature integrators (TTIs) developed using two different emulsification techniques. Weissela cibaria CIFP 009 cells, immobilized within 2% Na-alginate gel microbeads using homogenization (5,000, 7,000, and 10,000 rpm) and Shirasu porous glass (SPG) membrane technologies (10 μm), were applied to microbial TTIs. The prepared micobeads were characterized with respect to their size, size distribution, shape and morphology, entrapment efficiency, and bead production yield. Additionally, fermentation process parameters including growth rate were investigated. The TTI responses (changes in pH and titratable acidity (TA)) were evaluated as a function of temperature (20℃, 25℃, and 30℃). In comparison with conventional methods, SPG membrane technology was able not only to produce highly uniform, small-sized beads with the narrowest size distribution, but also the bead production yield was found to be nearly 3.0 to 4.5 times higher. However, among the TTIs produced using the homogenization technique, poor linearity (R²) in terms of TA was observed for the 5,000 and 7,000 rpm treatments. Consequently, microbeads produced by the SPG membrane and by homogenization at 10,000 rpm were selected for adjusting the temperature dependence. The E_a values of TTIs containing 0.5, 1.0, and 1.5 g microbeads, prepared by SPG membrane and conventional methods, were estimated to be 86.0, 83.5, and 76.6 kJ/mol, and 85.5, 73.5, and 62.2 kJ/mol, respectively. Therefore, microbial TTIs developed using SPG membrane technology are much more efficient in controlling temperature dependence.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.534-541
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• 2018

Kimchi (a traditional Korean fermented vegetable) was prepared with a starter, Lactobacillus zymae GU240 producing ${\gamma}$-aminobutyric acid (GABA), and one precursor of GABA (glutamic acid, glutamic acid monosodium salt (MSG), or kelp extract). L. zymae GU240, an isolate from kimchi, can grow at 7% NaCl and low temperature. Five different kimchi samples were fermented for 20 weeks at $-1^{\circ}C$. Kimchi with starter alone could not produce GABA. The GABA content was highest in kimchi with co-inoculation of the starter and MSG (1% (w/w)). Kimchi co-inoculated with the starter and kelp extract powder (3% (w/w)) had the second highest GABA content. Addition of glutamic acid powder (1% (w/w)) caused a reduction in the pH level of kimchi and growth inhibition of lactic acid bacteria and yeasts. Kimchi samples with MSG or kelp extract showed improvement of sensory evaluation scores. The results demonstrate the possibility to produce kimchi with improved functionality and taste by using L. zymae GU240 as a starter along with a suitable precursor such as MSG or kelp extract.

• 한국미생물·생명공학회지
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• 제17권2호
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• pp.88-93
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• 1989

Xylan성 biomass로부터 직접 alcohol을 얻고자 xylose 발효효모 X-6-41 균주의 NTG mutant인 X-6-41-1(his-) 균주와 xylanase 분비효모인 XB-33 의 NTG mutant XB-33-37(Arg-) 균주를 세포융합 시켰다. 원형질체 생성조건은 KYPX(XB-33), KYPD(X-6-41)에서 대수증식기 말기까지 증식한 세포를 집균하여 zymolyase(0.25mg/$m\ell$), cellulase (4mg/$m\ell$)와 100mM 2-mercaptoethanol 처리시 protoplast화 율은 X-6-41 경우 80%, XB-33인 45%로 나타났다. 선별된 융합체의 탄소자화능은 parent의 자화능을 서로 보완하였음을 확인하였고 xylan에서의 alcohol 발효는 2% xylan에서 발효 15 일만에 총당에 대해 0.28% alcohol 농도를 나타내었다. Parent와 fusant의 xylanase 활성은 완전배지 보다 최소배지상에서 높았는데 이것은 xylose 발효효모(X-6-41)의 경우 isoleucine에 의한 xylanase production inhibition 효과와 일치하였다.