• 제목/요약/키워드: Anaerobic respiration

검색결과 44건 처리시간 0.031초

포장방법에 따른 팽이버섯의 선도유지 효과 (Effect of Packaging Methods on Enoki Mushroom Qualities)

  • 신세희;정주연;최정희;김동만;정문철
    • 한국식품저장유통학회지
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    • 제16권2호
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    • pp.179-185
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    • 2009
  • 팽이버섯의 선도유지를 위한 적정 포장방법을 구명하기 위하여 팽이버섯의 호흡특성과 필름두께에 따른 기체조성을 사전 조사한 다음 현행 포장방법인 일반필름포장(PM)과 진공포장(VM), 그리고 $CO_2$ 25%와 50%, $O_2$ 10%와 20%를 각각 혼합하여 충전한 가스포장(AM)을 $1^{\circ}C$에서 12일 동안 저장하면서 선도유지특성을 비교하였다. 팽이버섯의 호흡 속도는 $0^{\circ}C$에서 $26.4\;mL{\cdot}CO_2/kg/hr$, $10^{\circ}C$ $80.0\;mL{\cdot}CO_2/kg/hr$, $20^{\circ}C$에서 $130.9\;mL{\cdot}CO_2/kg/hr$, $30^{\circ}C$에서 $173.5 \;mL{\cdot}CO_2/kg/hr$로 조사되었으며, 기체투과율이 좋은 LDPE 필름을 사용할 경우 40 및 $60{\mu}m$ 보다 $20{\mu}m$의 두께가 저장 12일까지도 생육최저산소농도를 훨씬 상회하는 안정된 상태를 나타내었다. 따라서 팽이버섯을 $20{\mu}m$의 LDPE 필름에 상기 각각의 포장방법을 적용하여 저장한 결과 AM에서는 고농도의 $CO_2$에 의한 호흡율 억제효과가 있었으며 진공포장을 제외한 모든 포장방법에서 저장 종료시점(12일)까지도 혐기적 호흡의 발생우려는 없었다. 중량감소율과 표면색은 $O_2$가 없는 VM에서 가장 억제되었으나 산소함유 포장방법 중에서는 50:10($%CO_2:%O_2$)의 AM이 가장 우수한 억제력을 나타내었다. 그러나 VM은 저장 2일경 심한 이취발생으로, PM은 저장 5일 경 높은 자루의 신장율로 상품성을 소실한 반면 AM의 여러 가스조성 중 50:10의 비율이 저장 12일 동안 이취, 변색 및 곰팡이 발생 등이 발생하지 않으면서 상품성을 유지하는 효과가 가장 높게 나타났다.

Reduction of quality of rice due to submergence during ripening stage and identification of its physiological cause

  • Lee, Hyeon-Seok;Back, Jung Seon;An, Sung Hyun;Jeong, Jae-Heok;Jeong, Han-Yong;Hwang, Woon-Ha;Yoon, Jong Tak;Lee, Gun-Hwi;Choi, Kyung-Jin
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.227-227
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    • 2017
  • This study was conducted to analyze the reduction of quality and ripening rate of rice due to submergence during ripening stage and identify the physiological cause. Korean japonica type rice cultivars, Nampyeong was used in the experiment. The following 7, 14 day after heading, they were then moved into submergence treatment facility and we conducted the tests under three different submergence conditions - T1(clear water and overhead submergence), T2(Muddy water and exposure of Flag leaf end ), T3(Muddy water and overhead submergence), and the treatment lasted for 4days. The decrease of ripening rate was most severe in T3 treatment at 7days after heading, and the decrease of head rice ratio was most severe in T3 treatment at 14days after heading. Meanwhile the starch synthesis was inhibited, as the supply of assimilation products was inhibited in grain during the submergence treatment. And in stem, sucrose content was increased because the soluble carbohydrates accumulated before heading were decomposed. These changes may be due to the consumption of respiratory substrate in anaerobic conditions and the inhibition of the production of photosynthetic products by light interception. In order to see what kind of reaction occurs at the molecular level, we examined the degree of RNA expression in grain, stem and leaf. First, the expression of rna associated with starch synthesis in grain was decreased in all submergence treatment. and especially Ospul(DBE) was more decreased in 14days after heading treatment than 7days after heading treatment. This difference can explain the result that the decrease of head rice ratio was more severe at 14days after heading. And in stem, the expression of rna associated with the supply of assimilation products was decreased in submergence treatment. Finally in leaf, the expression of rna(ADH, ALDH) associated with anaerobic respiration was increased, while the expression of rna associated with photosynthesis was decreased. These results of physiological analysis can used to develop the cultivation technique and to offer the information for breeding the cultivars with tolerant characteristics to submergence stress during ripening stage in rice.

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Measurement of Methane Production from Ruminants

  • Bhatta, Raghavendra;Enishi, Osamu;Kurihara, Mitsunori
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권8호
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    • pp.1305-1318
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    • 2007
  • On a global scale agriculture and in particular enteric fermentation in ruminants is reported to produce about one fourth (21 to 25%) of the total anthropogenic emissions of methane ($CH_4$). Methane is produced during the anaerobic fermentation of hydrolyzed dietary carbohydrates in the rumen and represents an energy loss to the host besides contributing to emissions of greenhouse gases into the environment. However, there appears to be uncertainty in the $CH_4$ estimation from livestock due to the limited availability of data to document the variability at the farm level and also due to the significant impact of diet on the enteric $CH_4$ production. The methane mitigation strategies require robust prediction of emissions from rumen. There are many methods available which would be suitable for measuring $CH_4$ produced from the various stages of animal production. However, several factors need to be considered in order to select the most appropriate technique like the cost, level of accuracy required and the scale and design of the experiments to be undertaken. Selection of any technique depends on the accuracy as each one has its advantages and disadvantages. Screening of mitigation strategies may be evaluated using individual animal before large-scale trials on groups of animals are carried out. In this review various methods for the estimation of methane production from ruminants as well as for the determination of methane production potential of ruminant feeds are discussed. The advantages and disadvantages of the methods starting from respiration chamber, ventilated hood, facemask, sulphur hexafluoride ($SF_6$) tracer technique, prediction equations and meteorological methods to in vitro methods are detailed.

Effects of dietary fermented spent coffee ground on nutrient digestibility and nitrogen utilization in sheep

  • Choi, Yongjun;Rim, Jong-su;Na, Youngjun;Lee, Sang Rak
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권3호
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    • pp.363-368
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    • 2018
  • Objective: The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Methods: Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum. Fermentation was performed at moisture content of 70% and temperature of $39^{\circ}C$ with anaerobic air tension for 48 h. Four adult rams (initial body weight = $56.8{\pm}0.4kg$) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in $4{\times}4$ Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. Results: In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p<0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Conclusion: Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed.

경부에 발생한 의인성 괴사성 근막염의 증례 (CASE REPORT OF NECROTIZING FASCITIS ON THE CERVICOFACIAL AREA)

  • 문철;이동근;성길현;박경옥;이재은;권혁도
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제16권1호
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    • pp.104-111
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    • 1994
  • Necrotizing fascitis is a severe soft tissue infection characterized by extensive necrosis of superficial fascia, suppurative fascitis, vascular thrombosis, widespread undermining of surrounding tissues. Associated systemic problems are widespread undermining of surrounding tissues, Associated systemic problems are common, with chronic alcoholism and diabetes being most prominent. Most commonly this disease presents in the extremities, trunk, and perineum. Necrotizing fascitis of dental origing is rare and its fulminating clinical course is not well documented in the dental literature. The present report is a case of necrotizing fascitis following vital extirpation of the pulp in a patient with uncontrolled diabetes mellitus and liver cirrhosis. Originally throught to be caused by hemolytic streptococcus organism or stphylococcus aureus, advances in anaerobic culturing have shown it to be a synergistic bacterial infection involving aerobic and ovligate anaerobes. it is relatively rare in relatively rare in haea and neck regions. If it was not diagnosed and treated in early stages, necrotizing fascitis can be potentially fetal, with a mortality rate approaching 40%. It's treatment requires early recognition, prompt and aggressive surgical debriment and proper supportive cares, such as, antibiotic therapy, fluid resuscitation and correction of metabolic and electrolyte disorder, resolving of the underlying systemic disease. Recently, we experienced two cases of necrotizing fascitis in cervicofacial region, One patient was 60 years old male with uncontrolled Diabetes Mellitus and other patient was 48 years old with steroid therapy during 30 years. Local surgical wound healing was successful but, patients were died after admission, because of lung abscess, gastrointestinal bleeding, septic shock and respiration hold.

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세척인삼 유통 현황과 포장전 2-phenylethyl Alcohol 훈증이 저장성에 미치는 영향 (Marketing of cleaned fresh ginseng and pre-packaging fumigation of 2-phenylethyl alcohol on ginseng storability)

  • 김선익;성봉재;김현호;황용수
    • 농업과학연구
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    • 제38권2호
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    • pp.205-212
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    • 2011
  • The potential factors for quality loss of cleaned fresh ginseng and technology to be associated with the improvement of marketability through pre-packaging fumigation were examined. Major microorganisms isolated from fresh ginseng included Botrytis cinerea, and Erwinia sp. Others such as Cylindrocarpon sp., Fusarium spp., Pennicilium spp., Bacillus spp. were also found at relatively low frequency. The bacterial density of vacuum packaged fresh ginseng rapidly increased during simulated marketing. Little correlation between bacterial growth and package swelling was found. In order to improve packaging method of fresh ginseng, pre-packaging treatment of 2-phenylethyl alcohol (PE, 100 uL/L, 4 hr) was examined. The fumigation treatment effectively inhibited the growth of bacteria density and also effective on keeping firmness of ginseng root, especially in cortical portion. The internal gas compositions of plastic container packaged for ginseng were approximately ranged between 6 to 8% $O_2$and 3 to 4% $CO_2$. The $O_2$ level of fumigation treatment was lower than control whereas $CO_2$ level was higher. The upsurge of ethylene evolution I day after simulated marketing was found only in fumigation treatment but it returned to ordinary level at day 2. The sucrose content of 2-PE treatment was significantly reduced at 5 days after simulated marketing but reducing sugars like glucose and fructose remained at higher level. The difference in sugar levels was reduced after 10 days of simulated marketing. The decay of fresh ginseng began at the lateral or fine root, which is weak to physical damage, in general. The epidermis was more damaged. Plastic container packaging with PE fumigation could be an alternative to vacuum packaging, which allows an aerobic environment and prevents anaerobic respiration. Further study of pre-package fumigation is required to improve technology of fresh ginseng marketing.

화학적 질식제 -청화물과 황화수소를 중심으로 (Chemical Asphyxiants - Cyanides and Hydrogen Sulfides)

  • 김양호;최영희;이충렬;이지호;유철인;이 현
    • 대한임상독성학회지
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    • 제1권1호
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    • pp.12-20
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    • 2003
  • Cyanides and hydrogen sulfide ($H_2S$) are major chemical asphyxiants. They have common mechanism of action which inhibit cellular respiration and induce histotoxic hypoxia. They do not generate ATP, and all processes dependent on ATP are stopped. No extraction of $O_2$ from blood decreases AV $O_2$ differences, and the shift to anaerobic glycolysis brings about lactic acidosis with high anion gap. The mainstay of the treatment is rapid treatment with appropriate use of antidotes. However, there are several differences between cyanides and $H_2S$. First, $H_2S$ is not metabolized by enzymes such as thiosulfate. Thus thiosulfate does not play any role in treatment of $H_2S$. Second, $H_2S$ is a more potent inhibitor of cytochrome aa3 than cyanide. Third, $H_2S$ induces more divergent neurologic sequele than cyanide. Finally, $H_2S$ is not absorbed via skin.

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서해 근소만 조간대 퇴적물에서 여름과 겨울에 인의 존재형태 (Phosphorus Speciation and Bioavailability in Intertidal Sediments of Keunso Bay, Yellow Sea During Summer and Winter)

  • 김동선;김경희
    • Ocean and Polar Research
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    • 제32권3호
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    • pp.177-186
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    • 2010
  • A sequential extraction technique was used to study sediment phosphorus speciation and its relative importance in the intertidal flat of Keunso Bay during summer and winter for a better understanding of the phosphorus cycle and bioavailability in intertidal sediments. Loosely sorbed P contents were the lowest among the five P-pools and showed little seasonal or spatial variation. Although Fe-bound P contents were almost constant in winter, they decreased rapidly with sediment depth in summer. The dissolution of Fe oxides, used as an oxidant for the anaerobic respiration, ascribed the rapid decrease of Fe-bound P in summer. Al-bound P contents displayed little seasonal variation, but showed a large spatial variation, with higher values in the upper intertidal flat. Comprising about 50% of total P, Ca-bound P contents were the highest among the five P-pools. Ca-bound P contents were higher in winter than summer, but did not exhibit a clear spatial variation. Organic P contents were higher in summer than winter, which was associated with higher primary production and clam biomass in summer. Organic P contents were higher in the lower intertidal flat than the upper intertidal flat. In Keunso Bay, bioavailable P contents of the intertidal flat comprising about one third of total P ranged from 2.41 to 5.09 ${\mu}molg^{-1}$ in summer and 3.82 to 5.29 ${\mu}molg^{-1}$ in winter. The bioavailability of P contents was higher in the lower intertidal flat than the upper intertidal flat, which was attributed to the large clam production in the lower intertidal flat.

질산화균 활성화조를 이용한 하수처리 공정에서의 유기물 및 질소, 인 제거에 관한 연구 (A Study on Removal of Organism and Nitrogen, Phosphorus in Wastewater Treatment Process Using Nitrifier Activated Reactor)

  • 동영탁;서동환;배유진;박주석
    • 상하수도학회지
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    • 제21권6호
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    • pp.727-735
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    • 2007
  • The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

산성광산배수의 망간처리를 위한 MOB 적용에 관한 연구 (A Study on the Application of Manganese Oxidizing Bacteria for Manganese Treatment in Acid Mine Drainage)

  • 이강유;장민;박인건;엄태영;임경호
    • 대한환경공학회지
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    • 제35권8호
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    • pp.564-570
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    • 2013
  • 산성광산배수처리를 위한 국내 대부분의 처리시설은 자연정화법을 사용하고 있으며 이들 중 일부 처리장에서는 고농도의 망간이 유출되고 있는데 이는 망간산화를 위해 높은 pH (>9)가 요구되기 때문이다. 본 연구는 망간처리 공정 중 경제성을 높일 수 있는 생물학적 망간처리의 가능성을 타진하는데 그 목적이 있으며 망간산화미생물은 Pseudomonas sp. MN5를 이용하였다. 회분식 실험을 통해 수질조건에 따른 영향을 분석한 결과 pH 7에서 최고산화속도는 $10.4mg/L{\cdot}h$로 나타났다. 망간산화미생물을 담지한 연속류 실험결과 운전 초기 망간 농도는 42 mg/L에서 6 mg/L 이하로 크게 감소하였지만 망간산화미생물의 산소소비에 의한 혐기조건 형성으로 망간의 재용출 현상이 나타났다.