• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.379-386
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• 1998

Deterioration of food is in general caused by the presence of microorganisms and chemical compounds of food itself. There exists antimicrobial compound in the food, however, addition of food antiseptics, additives, or physico-chemical processing is a common practice. The safety of artificial chemical antiseptics became a serious public concern, therefore, new natural antiseptic compounds are in need to be developed. We have isolated a new natural antifungal protein (KBS-B2) from Astragal seed through ammonium sulfate precipitation and column chromatography using FPLC Mono-S and Superose 12HR. The purified protein inhibited growth of Candida albicans, and spore germination of food spoiling fungi such as Aspergillus ochraceus, Penicillium expensum, P. digitatum and Botrytis cineria. Antifungal effect of the KBS-B2 protein could be directly assayed by bioautography overlaying the fungal spores on the electrophoresed acrylamide gel. The comparison of N-terminal amino acid sequences of the KBS-B2 with known antifungal protein revealed that had 50% homology to thaumatin and zeamatin like proteins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.987-994
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• 2000

Aspergillus coreanus NR 15-1, Asp. oryzae NR 15-3 and Asp. oryzae NR 2-5 isolated from traditional Korean nuruk were screened as parental strains producing starch hydrolyzing enzymes. They were mutagenized by N-methyl -N'-nitro-N-nitrosoguanidine (NTG) and mutants were isolated for analysis of various amylase activities and the ability of acid production. Among them, the mutants harboring high saccharogenic activity, dextrinogenic activity, and the ability of acid production were selected. Fifteen, six, and five strains of mutants were isolated from Asp. coreanus NR 15-1, Asp. oryzae NR 2-5, and Asp. oryzae NR 15-3, respectively followed by NTG mutagenesis. Among these mutants, thirteen strains were identified as auxotrophic mutants. \ulcorner (Arg.￣) mutant from Asp. coreanus NR 15-1 showed high glucoamylase activity and total acid productivity. Z6 (Ade.￣) mutant from Asp. oryzae NR 2-5 showed the highest $\alpha$-amylase activity, therefore \ulcorner and Z6 mutant were selected.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.11 no.2
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• pp.261-265
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• 2006

가. 젖소분을 이용하여 관행사육과 상자사육방식을 비교한 결과 단위면적당 3,000g(15${\times}$15${\times}$30,cm)으로 관행방식과 차이가 없었다. 나. 지렁이의 수직분포는 15cm이상에 대부분 분포하고 있었으나 관행방식은 0 ${\sim}$ 10cm에서 고르게 분포되어 있었으나 상자사육에서는 0 ${\sim}$ 5cm에 70%이상이 분포되어 기계화 채취에 적합한 것으로 판단되었다. 다. 분변토 분리 및 배출시험을 위하여 로드셀을 켈리브레이션 하였으며 이때 출력전압(v)과 중량과의 회귀관계는 Y = 0.004X + 1.0995로 나타났다. 라. 분변토 분리 및 배출 시험을 한 결과 축분처리상자를 개량전에는 분리 및 배출장치의 압축력이 평균 1.2kg/cm$^{2}$, 1.4kg/cm$^{2}$로 나타났으며 축분처리상자의 배출구를 1cm 높이고 폭을 10cm 줄여 개량후 배출장치의 압축력이 평균 0.6kg/cm$^{2}$, 0.5kg/cm$^{2}$로 압축력을 50%, 64%절감 시킬 수 있었다.

• Korean Journal of Organic Agriculture
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• v.8 no.3
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• pp.121-130
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• 2000

In order to screen the antagonistic bacteria which inhibit the growth of the plant pathogen, Penicillum expansum, we isolated an effective bacterial strain and investigated into the antifungal activity of the antagonist and it's identification. The eleven strains of bacteria which strongly inhibited P. expansum were isolated from the nature, and the best antagonistic bacterial strain designated as KB22, was selected. The antagonistic strain KB22 was identified to be the genus Bacillus subtilis based on morphological and biochemical characterization, The KB22 showed 55.9% of antifungal activity against the growth of P. erpansum. By the treatment of the culture broth and the heat treated culture filtrate of it, the B. subtilis KB22 showed 90% and 15% of antifungal activity, respectively.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.111-115
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• 2000

Fifty-two nematode predatory fungi were isolated from 37 soil samples collected from eight provinces in Korea. Isolated fungi were tested their predacity against Rhabditis sp. and Meloidogyne incognita in petri dish, and against M. incognita in greenhouse pot experiments. Fifty isolates had trapping organ of adhesive networks and two isolates had adhesive column or adhesive knob. In petri dish experiments, 5 1 isolates against Rhubditis sp. and 26 isolates against M. incognita showed over 91 % of predacity; in greenhouse experiments, however, only three isolates showed over 81% of predacity. These results imply that the results from the laboratory experiments are not consistent with those from the greenhouse experiments. Therefore, to select a promising biocontrol predatory fungi for plant-parasitic nematodes, the screening experiment should be conducted in conditions close to nature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.170-179
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• 1996

누룩은 생소맥을 조분쇄하여 물로 혼합시켜 자연적으로 공지중의 여러 종류의 미생물을 배양시켜 만들었다. 그러므로 누룩에서는 많은 종류의 사상균, 호모와 세균이 증식하였다. 누룩의 당화력은 원료 생소맥의 당화력과 대부분의 사상균의 당화력과 알붕의 세균성 당화력에 기인하여, 발효력은 누룩효모와 극소수의 사상균애 의하여 이루어지고 있다. 1945년 이전까지 누룩으로부터 12속 59종의 사상균이, 8속 29종의 효모와 4속 16종의 세균이 분리 되었다. 누룩사상균은 Aspergillus 속이 주종을 이루었고 Rhizopus속, Absidia속, Nucor속의 순으로 분포하고 있었고, Aspergillus속과 Rhizopus속은 중요한 누룩 당화균으로 작용하였다. 누룩의 대표적 효모는 Saccharomyces cerevisiae 이며 , 이균이 알코올 발효에 가장 큰 역할을 담당하며, Saccharomyces cerevisiae도 전통 민속주의 탁주와 약주의 발효역에 깊이관여한다고 사료된다. 누룩 중에 증식하는 세균은 양조학상 특별한 역할을 담당하지않지만 Bacillus 속 과 젖산세균이 많이 분리되었으며, 젖산세균은 담금초기에 pH의 안정화에 기여할 수 있다고 추측할 수 있다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.46-50
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• 1998

This study was peformed to improve extraction of insoluble proteins and to evaluate funtional properties of abolished proteins by the phytase produced by Asporgillus sp. The optimum pH, temperature, treatment time and unit of the enzyme for extraction of protein were pH 4.0~5.0, $50^{\circ}C$, 8~10 hrs and 120 units. The foaming capacity and foaming stability of sesame meal protein after enzyme treatment were virtually unchanged as compared to control. The emulsion capacity and emulsion stability of sesame meal protein was higher than control. Oil absorption as well as water absorption capacities of sesame meal protein were higher than control.

• Korean Journal of Microbiology
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• v.25 no.2
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• pp.129-136
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• 1987

Nitrogen fixing activity associated with 40 varieties of rice was assayed at heading stage by an in situ acetylene reduction method. The in situ acetylene reduction activity and population of nitrogen fixing bacteria obtained on nitrogen-free malate medium for Azospirillum spp. enrichment showed positive correlation. Six Azospirillum spp. with high nitrogenase activity were isolated from the rice roots, from which five spp. were identified as A. lipoferum and one was A. brasilense. The physiological characteristics of the six Azospirillum isolates, that is, carbon source utilization, biotin requirement, antibiotic resistance, indole acetic acid excretion, plasmid profile and protein patterns were compared.

• Computational Structural Engineering
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• v.11 no.4
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• pp.331-340
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• 1998

본 연구에서는 이동제한장치가 있는 연속교의 지진응답특성을 고찰하였다. 일점고정연속교에 있어서 이동제한장치는 교각이 탄성거동을 하는 경우 교축방법 수평력 분산기능이 있으며 교각하부에 소성힌지가 발생하거나 내진분리베어링이 있는 경우에는 최대변위 및 비탄성거동에 따른 잔류변위제한에 매우 효과적이다. 상부구조와 이동제한장치의 충돌시 발생하는 충격력은 완충재의 사용으로 상당히 감소시킬 수 있다. 이동제한장치의 설치위치 및 이격거리는 이동제한장치가 설치될 하부구조의 강성 및 강도와 온도변화, 급제동력, 작은 지진발생시 충돌여부, 신축이음장치유간 등을 고려하여 결정되어야 한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.607-612
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• 1993

원심분리기는 용액 속에 있는 물질을 크기와 밀도 및 모양의 다름을 이용하여 용액으로부터 분리, 정제 및 순화하는 과학기계이며 처리량의 규모에 따라 공업용과 실험실용으로 분류된다. 공업용은 처리량이 많은 반면 실험실용은 처리량이 적으나 분리효과가 좋은 특징을 갖으며 회전속도에 의해 저속, 고속 및 초고속의 원심분리기로 나뉘어진다. 초고속 원심분리기는 최초(30년대)에 침전계수의 측정을 목적으로 연구개발을 시작하였다. 이의 용도에서 사용되는 초고속원심기를 분석용 초고속원심기라 부르나 이는 50년대 이후에 점차적으로 기술적 발전을 가져와 미소물질 분리를 위한 분리용 초고속원심기로 변천이 되어 생물학분야 이외에 항공기,선박,고속철도,석유탐지,원자력,섬유공업과 반도체등 여러 분야에 이용이 되고 있다.