• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.73-74
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• 2013

In this study, we examined the properties of the concrete for the adsorption of carbon dioxide by adding in photosynthetic bacteria. As for the experimental plan, we measured slump, carbon dioxide concentration and compressive strength. The findings revealed the non-plastic cement added with photosynthetic bacteria had the greatest flexibility and showed carbon dioxide absorption and condensation delay due to the sugar constituents of photosynthetic bacteria. Giver the progress in the studies on the strength development, it is estimated to be used as CO₂ reduction concrete.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.714-718
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• 1998

Various mutants either lacking or having decreased levels of light-harvesting complexes and reaction center complex were obtained with a high frequency by an increased formation of poly-3-hydroxybutyrate (PHB) in Rhodobacter sphaeroides. One of the photosynthesis-defective mutants, PY-17, which was devoid of any of the light-harvesting complexes (B800-850, B875) as well as the reaction center complex, was analyzed further. The mutant showed substantial transcription of the puhA, pufKBALMX, and pucBAC operons coding for the structural proteins of the photosynthetic complexes although each of the activities was lower than that of the wild type. Translation of the pufKBALMX and pucBAC operons were also active in the mutant although with activities different from the corresponding one of the wild type. From these results the mutation appears to exert its effect at the post-translational level of the photosynthetic complex assembly. Complementation of the photosynthesis-defective phenotype of the mutant was achieved with an about 12-kb DNA region containing the puhA gene. The relationship between the formation of PHB and photosynthetic complexes is discussed.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.442-449
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• 2004

Improving the light utilization efficiency of photosynthetic cells in photobioreactors (PBRs) is a major topic in algal biotechnology. Accordingly, in the current study we investigated the effect and suitability of photosynthetic pigment reduction for improving light utilization efficiency. The light-harvesting complex II (LH-II) genes of Rhodobacter sphaeroides were removed to construct a mutant strain with less pigment content. The mutant strain exhibited a slower growth rate than the wild-type under a low light intensity, while the mutant grew faster under a high light intensity. In addition, the specific absorption coefficient was lower in the mutant due to its reduced pigment content, thus it seemed that light penetrated deeper into its culture broth. However, the distance (light penetration depth) from the surface of the PBR to the compensation point did not increase, due to an increase in the compensation irradiance of the mutant strain. Experimental data showed that a reduced photosynthetic pigment content, which lessened the photoinhibition under high-intensity light, helped the volumetric productivity of photosynthetic microorganisms.

• 생명과학회지
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• 제8권5호
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• pp.557-562
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• 1998

토양수분이 한발상태에서 적습상태로 변동되었을 때, 콩의 광합성속도, 증산작용, 기공전도도 및 엽내수분의 변화와 이들 형질간의 상호연관성을 구명하기 위하여 본 실험을 수행하였던 바 그 결과를 요약하면 다음과 같다. 한발상태에서 적습상태로 토양수분 함량을 변동시켰을 때, 광합성속도, 증산작용, 기공전도도 및 잎의 함수량은 재관수후의 시간이 경과함에 따라 증가하는 경향이었는데, 광합성속도는 증산작용보다 빠른 회복을 보였고 품종간의 일정한 경향은 보이지 않았다. 광합성속도와 엽내수분, 기공전도도와 엽내수분 및 광합성속도와 기공전도도간에는 모두 정(正)의 상관관계가 인정되었는데, 특히 광합성속도와 엽내수분간의 상관계수가 가장 높아 양자간의 밀접한 관계를 나타내었다.

• 한국작물학회지
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• 제48권1호
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• pp.25-30
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• 2003

This research was conducted to compare the dry matter production and the yield productivity among nine soybean cultivars by measuring the photosynthetic ability of the middle and lower leaves at the flowering and the seed development stages. The leaf greenness(SPAD value) were ranged as 32-42 at the flowering stage. Also, They were ranged as 25-40 and 38-51 at the fifth leaf and the seventh leaf, respectively. The photosynthetic ability at the flowering and the seed development stage showed significant differences among soybean cultivars, and the photosynthetic ability at the seed development stage showed higher difference among cultivars than the flowering stage. The variation of the photosynthetic ability at the flowering and the seed development stage also was significant among cultivars. The light saturation point at the flowering stage was about 1500 $\mu$mol $m^{-2}$ $s^{-1}$ PAR, and the seed development stage was about 1000 $\mu$mol $m^{-2}$ $s^{-1}$ PAR. The photosynthesis showed the high negative correlation with the leaf area and the positive correlation with the leaf area ratio. Also, photosynthesis at seed development stage showed positive correlation with grain yields but there was not significant between photosynthesis and yields at flowering stage..

• 한국대기환경학회지
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• 제12권3호
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• pp.263-268
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• 1996

This study was conducted for the assessment of the effects of acid rain and soil fertilizers on photosynthetic rate, was content, and contact angle on 5-year seedlings of Japanese red pine (Pinus densiflora Sieb. et Zucc.) leaves. The seedlings were exposed to pH 3.0 (simulated acid rain), pH 6.5 (groung water) and rain (pH around 4.6). The seedlings were also treated with $Ca(OH)_2, Mg(OH)_2, and Ca(OH)_2 + Mg(OH)_2 + C.F.(compound fertilizer)$. Photosynthetic rate, stomatal conductance, was content, contact angle value, and mineral nutrient content of the leaves were measured and the results were as follows: 1. Photosynthetic rate and stomatal conductance of the leaves increased with the increase of pH. Photosynthetic rate and stomatal conductance increased with application of soil fertilizer in the pH 3.0 treatment, but showed no changes in the rain and the pH 6.5. 2. Contact angle value and was content of the leaves did not change with the pH treatment, but increased with the fertilizer treatments. 3. Mineral nutrient contents of the leaves were lowest in the rain treatment and highest in the pH 6.5 treatment. The increase of mineral nutrient contents was observed with the soil fertilizer treatments.

• Environmental Engineering Research
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• 제19권3호
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• pp.293-298
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• 2014

An anaerobic photosynthetic treatment process utilizing purple non-sulfur photosynthetic bacteria (PNSB) was applied to the recovery of organic carbon from food processing wastewater. PNSB cells, by-product from the treatment, have high nutrition such as proteins and vitamins which are a good alternative for fish feed. Effects of light source on performance of anaerobic photosynthetic process were investigated in this study. Two bench-scale photo-bioreactors were lighted with infrared light emitting diodes (LEDs) and tungsten lamps covered with infrared transmitting filter, respectively, aiming to supply infrared light for photosynthetic bacteria growth. The photo-bioreactors were operated to treat noodle-processing wastewater for 323 days. Hydraulic retention time (HRT) was set as 6 days. Organic removals in the photo-bioreactor lighted with infrared LEDs (91%-95%) was found higher than those in photo-bioreactor with tungsten lamps with filter (79%-83%). Biomass production in a 150 L bench-scale photo-bioreactor was comparable to a 8 L small-scale photo-bioreactor in previous study, due to improvement of light supply efficiency. Application of infrared LEDs could achieve higher treatment performance with advantages in energy efficiency and wavelength specifity.

• 원예과학기술지
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• 제31권2호
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• pp.146-152
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• 2013

토마토 잎들의 엽위별 광합성 특성을 조사하고, 잎의 연령과 개화속도를 엽위별 광합성 특성과 비교분석하였다. 일중 광합성 속도 특성실험에서는 일출 전 2시간부터 일몰 후 3시간까지 1시간마다 4번째 화방의 하부엽 3매의 광합성 속도를 측정하였다. 3개체를 반복으로 총 2회 조사하였다. 토마토의 일중 광합성 속도는 일출 후 1시간 동안 급격히 증가한 후, 일몰 2시간 전까지 일정하게 유지되는 양상을 보여 급액의 시작과 마감시각을 결정하는데 적용할 수 있을 것으로 사료된다. 엽위별 광합성 속도 특성실험에서는 1화방부터 4화방까지 각 화방의 하부에 있는 본엽 3개씩을 대상으로 광합성 속도를 조사하였다. 또한 광합성 특성을 분석하는데 적용하기 위해 개화속도를 조사하였다. 광합성속도는 엽위에 관계없이 꽃이 만개하는 시기를 정점으로 지속적으로 감소하는 경향을 보였다. 이는 만개 이후에는 해당 화방 이하의 잎의 활력이 감소하고 생육단계가 노화단계로 이동하기 때문으로 사료된다. 따라서 토마토의 개화속도와 광합성 속도는 서로 밀접한 관련이 있는 것으로 나타났다. 연구결과, 생육단계(엽령)의 차이에 의해 각 화방별 광합성 속도는 차이가 있으나, 광합성 속도로 작물의 활력을 판단하려 할 때는 개화하고 있는 화방의 하부엽을 조사하는 것이 매우 효과적일 것으로 판단된다.

• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.315-323
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• 2005

The integrated or the two-stage (dark anaerobic and photosynthetic) fermentation processes were compared for the hydrogen production using purple non-sulfur photosynthetic bacteria, Rhodopseudomonas palustris P4. Cell growth, pH changes and organic acids and bacteriochlorophyll contents were monitored during the processes. Culture broth of Rps. palustris P4 exhibited dark-red during the photosynthetic culture condition, while yellow under the anaerobic condition without light. Rps. palustris P4 grown at the photosynthetic condition evolved 0.38 and 1.33 ml $H_2$/mg-dcw during the dark and the light fermentation, respectively, which were totally 1.71 ml $H_2$/mg-dcw at the two-stage fermentation. The rate of hydrogen production using Rps. palustris P4 grown under the dark anaerobic condition was 2.76 ml $H_2$/mg-dcw which consisted of 0.46 and 2.30 ml $H_2$/mg-dcw from the dark and the photosynthetic fermentation processes, respectively. Rps. palustris P4 grown under dark anaerobic conditions produced $H_2$ 1.6 times higher than that of grown under the photosynthetic condition. However, total fermentation period of the former was 1.5 times slower than that of the latter, because the induced time of hydrogen production during the photosynthetic fermentation was 96 and 24 hours when the seed culture was the dark anaerobic and photosynthetic, respectively. The integrated fermentation process by Rps. palustris P4 produced 0.52 ml $H_2$/mg-dcw(1.01 mol $H_2$/mol glucose), which was 20% of the two-stage fermentation.

• 한국농림기상학회지
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• 제7권3호
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• pp.220-226
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• 2005

오존 노출이 버즘나무의 광합성 특성에 미치는 영향을 조사하기 위하여, 2년생 버즘나무 유묘에 하루에 8시간씩 100 ppb의 오존을 처리하였다. 오존 처리를 진행하는 동안, 3주마다 버즘나무의 엽내 엽록소 함량과 광합성 특성을 측정하였다. 오존에 의한 잎의 가시적 피해는 나타나지 않았으며, 또한 엽내 엽록소 함량은 대조구와 뚜렷한 차이를 보이지 않았다. 그러나 광합성량, 기공전도도, 수분이용효율은 오존 처리 6주 후에 대조구보다 감소하였다. 한편 탄소고정효율과 광화학 효율은 오존 처리 3주와 6주 후에서 감소한 것으로 나타났다. 위의 결과를 토대로 볼 때, 탄소고정효율은 오존 스트레스에 가장 민감한 파라미터로 나타났으며, 이것은 오존 민감성을 평가하기 위한 매우 적당한 지표로 생각되었다.