• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 2000.05a
• /
• pp.23-28
• /
• 2000

• Microbiology and Biotechnology Letters
• /
• v.23 no.6
• /
• pp.763-769
• /
• 1995

As a mean to recover photosynthetic bacterial(PSB) cells and its practical uses in food industrial wastewater treatment, various biodegradable polyelectrolytes were first investigated for flocculation of suspended colloids in the PSB treatment process of soybean curd wastewater. Anionic polyelectrolytes such as sodium alginate and carrageenan were not effective but a cationic polyelectrolyte chitosan isolated from Portunus trituberclatus showed very effective flocculation activity. The concentration of chitosan, pH and temperature of wastewater for maximal flocculation were 40 mg/l, pH 7 and room temperature, respectively. Test using deacetylated chitosan to various degree showed higher flocculating activities in samples deacetylated over 75% and time for maximum flocculation was 40 min by stirring slowly under the above optimal conditions. Chitosan was not only effective to flocculate cells but also removed COD and MLSS of the wastewater. COD of 42% and MLSS of 87% were removed by addition of chitosan to the soybean curd wastewater treated with PSB.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.11a
• /
• pp.89-90
• /
• 2018

In recent years, harmful substances and fine dust in the air are caused by respiratory and cardiovascular diseases through various mechanisms when they are introduced into the human body through respiration, thereby exacerbating human health and causing cancer by prolonged exposure do. In order to prevent such fine dust from being introduced into the room and to improve indoor air quality, improvement of air quality has attracted attention. Among indoor air pollutants, fine dust and CO₂ are pollutants that are directly affected by indoor number and activity. The purpose of this study is to evaluate the basic performance of cement matrix using photosynthetic bacteria as a basic study of fine dust and CO₂ adsorption type matrix to suppress indoor air pollution and improve air quality.

• Journal of Marine Bioscience and Biotechnology
• /
• v.14 no.2
• /
• pp.112-123
• /
• 2022

Photosynthetic bacteria (PSB) play an important role in water purification, and their application is beneficial for sustainable aquaculture. However, maintaining the microbial stability of PSB from subculturing to preservation is a challenging task. Since improvement in the microbial stability of PSB is a crucial parameter, optimized conditions for cell immobilization and lyophilization were investigated. In PSB immobilization, 0.1-M CaCl₂ was found to be the most effective divalent metal ion solution in terms of cost-effectiveness, resulting in beads with a 4-mm diameter and high loading (1.91×10⁹ CFU/mL) of viable cells. Maintenance of cell viability, external appearance, and color of PSB beads was best in 3.5% NaCl during storage. In lyophilization, the addition of skim milk (9%) and dextrose (2%) as cryoprotective additives allowed the highest cell viability. Over an 18-week shrimp breeding period, when optimally manufactured beads and lyophilized powder of PSB were applied to shrimp aquaculture water, NH⁴⁺, NO₃^-, and NO₂^- were more effectively removed by 55%, 100%, and 100%, respectively, compared to controls. Thus, microbial stability of PSB through optimized cell immobilization and lyophilization was successfully enhanced, enabling a wide application.

• KSBB Journal
• /
• v.20 no.6
• /
• pp.393-400
• /
• 2005

Hydrogen($H_2$) as a clean, and renewable energy carrier will be served an important role in the future energy economy. Several biological $H_2$ production processes are known and currently under development, ranging from direct bio-photolysis of water by green algae, indirect bio-photolysis by cyanobacteria including the separated two stage photolysis using the combination of green algae and photosynthetic microorganisms or green algae alone, dark anaerobic fermentation by fermentative bacteria, photo-fermentation by purple bacteria, and water gas shift reaction by photosynthetic or fermentative bacteria. In this paper, biological $H_2$ production processes, that are being explored in fundamental and applied research, are reviewed.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.4
• /
• pp.643-648
• /
• 2002

For wastewater treatment and utilization of the biomass, a photosynthetic bacterium was isolated based on its cell growth rate, cell mass, and assimilating ability of organic acids. The isolate was a Gram-negative rod-shaped bacterium that contained a single polar flagellum and formed a lamellar intracytoplasmic membrane (ICM) system, including bacteriochlorophyll $\alpha$. The major isoprenoid quinone component was identified as ubiquinone Q-10, and the fatty acid composition was characterized as to contain relatively large amount of C-16:0 (18.74%) and C-18:1 (59.23%). Based on its morphology, phototrophic properties, quinone component, and fatty acid composition, the isolate appeared to be closely related to the Rhodopseudomonas subgroup of purple nonsulfur bacteria. A phylogenetic analysis of the isolate using its 16S rRNA gene sequence data also supported the phenotypic findings, and classified the isolate closely related to Rhodopseudomonas palustris. Accordingly, the nomenclature of the isolate was proposed as Rhodopseudomonas palustris KUGB306. A bench-scale photosynthetic bacteria (PSB) reactor using the isolate was designed and operated for the treatment of soybean curd wastewater.

• Transactions of the Korean hydrogen and new energy society
• /
• v.16 no.4
• /
• pp.315-323
• /
• 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.

• Ceramist
• /
• v.21 no.3
• /
• pp.233-248
• /
• 2018

Photosynthesis of plant, algae, and certain types of bacteria can convert solar energy to electrons at high efficiency. There have been many research investigations to utilize this mechanism to develop photosynthetic bio-solar energy systems. In this article, the fundamentals of photosynthetic energy conversion mechanism are explained and various approaches are introduced and discussed.

• Journal of Korean Society on Water Environment
• /
• v.20 no.4
• /
• pp.339-345
• /
• 2004

The characteristics of $H_2$ production from livestock wastewater were investigated through an anaerobic acid forming process using Clostridium beijerinckii and the photosynthetic process using Rhodobacter sphaeroides. The submerged separation membrane was installed in the acid forming reactor, The photosynthetic process is composed of two reactors(photosynthetic reactor 1 and photosynthetic reactor 2) which is connected continually. The removal rate of COD and the production of volatile fatty acid(VFA) in the acid forming process were approximately 50% and 1000mg/L, respectively. The 70% of COD in the effluent of acid forming process was removed through the photosynthetic process. The production of $H_2$ in the photosynthetic reactor 1 and 2 was 50 and $25mLH_2/gVFA_{COD}$, respectively. The values of Y in acid forming reactor, photosynthetic reactor 1 and 2 was 0.2263, 0.0601 and 0.0393, respectively. The acetic acid and butyric acid produced in acid forming process were converted to $H_2$ by photosynthetic bacteria.

• The Korean Journal of Food And Nutrition
• /
• v.10 no.4
• /
• pp.509-513
• /
• 1997

The photosynthetic bacteria, Rhodopseudomonas capsulata H161, were grown anaerobically in the Modified Ormerod medium for 5 days. The optimum temperature and pH for growth and carotenoid pigment of the organism were observed at 3$0^{\circ}C$, and around pH 7.4, respectively. The optimum condition of producing the carotenoid pigment, light intensity 5,000 lux. The photosynthetic bacteria, Rhodopseudomonas capsulata H161, produced large amount of carotenoid pigment, which identified to 4 carotenoid components containing; spheroidene, rhodovibrin, spirilloxanthin, lycopene.