• 한국식품영양과학회지
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• 제41권11호
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• pp.1619-1625
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• 2012

김장김치를 김치냉장고에서 6개월간 '숙성 후 저장'과 '저온 저장' 모드에서 저장하였을 때 발효 양상을 비교해 보았다. 본 연구에 사용한 '숙성 후 저장' 모드에 보관한 김치는 $10^{\circ}C$에서 5일간 발효시킨 후 $-2.5^{\circ}C$에 저장한 F1김치, $15^{\circ}C$에서 1일 발효시킨 후 $-2.5^{\circ}C$에서 저장한 F2김치이고, '저온 저장'에 보관한 김치는 담금 즉시 $-1^{\circ}C$에 저장한 S1김치와 $-2.5^{\circ}C$에 저장한 F2김치 4종류이다. '숙성 후 저장'한 F1김치는 2주에 pH 4.4, 그리고 산도는 0.6%로 숙성기에 접어들었으나 F2김치는 8주, '저온 저장'한 S1김치는 12주에 그리고 S2김치는 저장 말기에 숙성기로 접어들었다. Lactobacillus spp. 생육은 F1 및 F2김치에서는 저장 초기부터 급속히 증식하여 8주에 최대 균수인 8.0~9.0 log CFU/mL에 도달한 후 F1김치에서는 균수가 6개월간 지속된 반면, F2김치에서는 저장 12주 이후 감소하였다. S1과 S2김치에서는 8주에 최대 균수인 6.8 log CFU/mL에 도달하여 적숙기 최대 균수에 미치지 못하였다. Leuconostoc spp.는 저장모드에 따라 최대 생육 시점은 다르나 8.0~9.0 log CFU/mL에 도달하였다. F1김치의 Leuconostoc spp.는 6개월 동안 지속적으로 성장하여 최대 생육에 도달한 반면, 다른 김치 시료에서는 최대 생육 후 균이 감소하였다. 고온 젖산균인 Lactobacillus spp.의 생육은 '저온 저장'한 김치에서 억제되었으나 Leuconostoc spp.의 생육은 $-2.5^{\circ}C$와 같이 낮은 온도에서도 최대 생육을 하였다. 김장김치의 관능은 저장 3개월까지 외관, 신맛, 탄산미, 아삭아삭함에서 F1김치가 가장 높은 평가를 받았는데 이는 Lactobacillus spp.와 Leuconostoc spp.의 균수가 가장 높았기 때문으로 생각된다. 6개월 후에는 F1와 S1김치가 높은 평가를 받았는데, S1김치는 저장 말기에 신맛과 탄산미가 증가하는 현상을 보였는데, 이는 Leuconostoc spp.의 균수 저장 후기에 높아졌기 때문으로 생각된다. 이상의 결과를 종합해 보면 김장김치를 저장 기간 내 맛있게 먹기 위해서는 김치를 완전히 숙성시킨 후 저온에서 저장하는 방법인 $10^{\circ}C$에서 5일 동안 발효시켜 $-2.5^{\circ}C$로 온도 변환하는 시스템이 가장 우수하였다. '저온 저장' 온도로는 $-1^{\circ}C$가 $-2.5^{\circ}C$보다 우수하였다.

• 한국조경학회지
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• 제46권2호
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• pp.62-68
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• 2018

본 연구는 실내공간을 모형화한 아크릴챔버($600{\times}800{\times}1,200mm$, $L{\times}W{\times}H$)와 공기정화 장치인 그린바이오필터($495{\times}495{\times}1,000mm$, $L{\times}W{\times}H$)를 아크릴로 제작하여 광량 0, 30, $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$의 3수준에 따른 디펜바키아와 스파티필럼의 미세먼지(PM10) 및 초미세먼지(PM1) 제거능과 두식물의 광합성율, 기공전도도, 기공수를 비교하였다. PM10이 $1{\mu}g$이 될 때까지 걸리는 시간에 있어서 디펜바키아는 광의 유무에 따른 차이가 유의하게 나타났으며, 30과 $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$에서는 유의적인 차이가 없었다. 스파티필럼은 0과 $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$에서는 유의적인 차이가 없었으나, $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$에서 유의적인 차이를 보였다. 90분 경과 후, $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$에서 스파티필럼의 PM1, PM10 잔존량이 가장 적었으며, 이때 이산화탄소 잔존량도 가장 낮은 것으로 나타났다. 스파티필럼은 $0{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}PPFD$에서도 PM1, PM10 잔존량이 디펜바키아보다 낮은 것으로 나타났다. 두 식물 모두 광량이 높을수록 광합성율이 높게 나타났으며, 기공전도도는 유의적인 차이가 없었다. 스파티필럼은 디펜바키아보다 광합성율과 기공전도가 높았고, 기공수가 많았으며, 잎의 앞 뒷면 모두에서 기공이 관찰되었다. 이러한 식물적 특성으로 인하여 같은 광량에서 스파티필럼의 공기정화 효과가 디펜바키아보다 더 좋았던 것으로 판단된다. 따라서 효과적인 실내 미세먼지 제거를 위해서는 실내광량에 따른 식물의 광합성율과 기공수, 기공의 배치형태 등 식물 각각의 특성을 고려해야 할 것으로 판단된다.

• 한국축산식품학회지
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• 제29권3호
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• pp.325-333
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• 2009

쇠고기의 저장 중 이취발생을 대변할 수 있는 품질인자를 탐색하고자 온도의존성의 관점에서 상호관계를 분석하였다. 특수관능기법인 R-index에 의한 이취검지시간을 탐지하였고, 이화학적, 생물학적 품질인자를 측정하였다. 먼저, 이취검지시간의 온도의존성의 관계식을 개발하여, 이에 따른 이취발생 indicator의 선발 요건을 유도하였다. 이화학적 분석은 VBN, pH, 육색, Warner-Bratzler shear force,그리고 생물학적 분석은 Pseudomonas spp., Lactic acid bacteria를 대상으로 하였다. 품질인자의 온도의존성은 Arrhenius 상수인 활성화에너지를 사용하여 분석하였다. 그 결과 VBN, pH, $a^*$값, LAB, Pseudomonas spp., WBSF, $L^*$값, $b^*$값의 순으로 이취발생과의 온도의존성이 유사하게 나타났으며, 상위권에 있는 pH와 $a^*$값에 비하여 환경적 요인에 안정한 VBN이 쇠고기 저장 중 이취발생의 최적 indicator인 것으로 탐색되었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.332.2-333
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• 2002

Three alkaline proteases. designated JB-1. JB-2, and JB-3, are extracellular enzymes produced by Bacillus spp. JB411 which was isolated korean soil. They were separated by DEAE-sepharose CL-6B gel. and further purified using ammonium sulfate precipitation. ultra membrane filtration. and Ultrogel AcA gel filtration. The optimun pH values of proteases IB-1. JB-2. and JB-3. were shown to be 9.5. 9.5 and 7.5. respectively. All three proteases were stable in the pH range of 5-11. (omitted)

• KSBB Journal
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• 제11권5호
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• pp.572-576
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• 1996

Conditions for the culture of Pleurotus spp. mycelium using rancid frying oils were investigated. Among the six strains tested, Pleurotus ostreatus CBS 03 showed the greatest mycelial growth on fish paste and ramyon frying oil, and was used in this study. The optimum temperature and pH for mycelial growth were from 25 to $30^{\circ}C$ and pH 5.5 to 6.0, respectively. Tryptone for mycelial growth was better than any other nitrogen sources. The addition of $KH_2PO_4 and MgSO_4$ enhanced mycelial growth at 0.2 and 0.01% on fish frying oil, and at 0.1 and 0.03% on ramyon frying oil. Among the vitamins used, thiamine and nicotinic acid were the most effective ones.

• Toxicological Research
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• 제14권3호
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• pp.341-348
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• 1998

We established an in vitro experimental system using the following procedure. We first introduced tritium-labelled norepinephrine ([3H]-NE)into PC12 cells. The [3H]-NE incorporated into PC12 cells were then stimulated by a high concentration (60 mM) of $K^+$ during 12 minutes. Then, we counted the amount of [3H]-NE release from PC12 cells with the scintillation counter. After screening fungal, Streptomyces or bacterial product using this experimental system, we obtained S9940 from Streptomyces spp. which inhibited [3H]-NE release from PC12 cells. S9940 also inhibits the release of ATP as a neurotransmitter of PC12 cells and rat cortical neurons. The inhibitory effect was seen even when the PC12 cells were treated with low $K^+$ buffer containing ionomycin $(1\muM)$ as an ionopore. This result suggests that the inhibitory action of S9940 on neurotransmitter release appeared after the influx of $Ca^{2+}$.

• 한국가금학회지
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• 제27권1호
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• pp.31-35
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• 2000

This study was investigated to observe Lactobacillus spp. population of poultry digestive organ, duodenum, ilium, cecum and colon by growing steps and to select of valuable lactobacilli as probiotics. Two strains of male broiler commercial chickens, Hybrid and Ross, were used to evaluate population of Lactobacillus spp. in intestinal tracts. Three strains of Lactobacillus were identified, and bile salts environment. The number of lactovacilli was the lowest in duodenum compared to other intestinal tracts which had similar population. Population of Lactobacillus was maintained constantly regardless growing steps after one week of age. Identification of Lactobacillus from cecum resulted in L.reuteri BC5, L. crispatus BC7, L.reuteri BC9. All strains was depressed in pH 1 and 2, although two strains could survive for one hour at pH 2. And they could survive at pH 4 for 4hours. In bile salts tolerance, L.reuteri BC5, L.crispatus BC7 were maintained for 2 hours, but the growth reduced from 2hours. Growth of L.reuteri BC9 was increased continuously. In conclusion, Lactobacillus of intestinal tracts were established at first week, and maintained constant population. They were influenced on severe acidic condition and bile salts. Cecal Lactobacillus has different growth charcteristics by strains.

• 한국미생물·생명공학회지
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• 제40권4호
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• pp.356-363
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• 2012

The aim of this study was to utilize rice bran, the main waste product of paddy processing, in xanthan gum production by Xanthomonas campestris fermentation. Deffated rice bran was enzymatically hydrolyzed using cellulase, gluco-amylase, alpha-amylase and xylanase at various pHs and temperatures within 0-12 h. The highest sugar content reached at $35^{\circ}C$, pH 5.5 in 6 h with 41.66%. The enzymatic hydrolysate was used as the carbon source for xanthan gum production by X. campestris NRRL B-1459 and X. campestris pv. campestris. The highest productivities obtained were 21.87 and 17.10 g/L, respectively. Viscosity measurement for the obtained xanthan gums and commercial gum was carried out in gum solutions at various pHs and temperatures. The highest viscosity was reached with 1% gum solutions at $20^{\circ}C$ and pH 5.5 for all gums with viscosity values of 470, 131 and 138 mPa sec, respectively. This work has provided relevant scientific information about the use of rice bran, an abundant agroindustrial residue, to produce xanthan gum.

• 미생물학회지
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• 제15권3호
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• pp.123-130
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• 1977

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10/sup -4/ -10/sup -6/M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• The Korean Journal of Ecology
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• 제21권5_1호
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• pp.449-456
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• 1998

This study was carried out to investigate the characteristics of acid deposition by stemflow, throughfall, rainfall and $SO_{2}$ in the industrial, urban and rural areas where were affected by the acid rain areas air pollution in Pinus thunbergii than Quercus spp. forest. As the stemflow pH in industrial and urban area were lowed that of rural area, the result industrial and urban, and correlation of negative ($r=-0.9415^{**}$) between pH and EC. The concentration of acid ion by stemflow, throughfall, rainfall were high $SO_{4}^{2-}$ ion at industrial areas, especially of $NO_{3}^{-}$ ion at urban areas. The concentration of basic ion all rain fall were high $Ca^{2+},\;Na^{+}$ ion at industrial areas, but there were high $Ca^{2+}$, $Na^{+}$ ion at urban areas. The concentration of $SO_{2}$ at survey areas were high $SO_{2}$ concentration at industrial and urban areas, but there was low at rural areas. There was correlation of negative ($r=-0.8007^{**}$ between pH and $SO_{2}$ concentration at survey areas. Soil acidity was also affected by stemflow and showed sigificantly low pH in industerial and urban areas.