• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.283-291
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• 2019

Fermentation of food waste in the presence of different concentrations of salt ($Na^+$) and ammonia was conducted to investigate the interrelation of $Na^+$ and ammonia content in bio-hydrogen production. Analysis of the experimental results showed that peak hydrogen production differed according to the ammonia and $Na^+$ concentration. The peak hydrogen production levels achieved were (97.60, 91.94, and 49.31) ml/g COD at (291.41, 768.75, and 1,037.89) mg-N/L of ammonia and (600, 1,000, and 4,000) $mg-Na^+/L$ of salt concentration, respectively. At peak hydrogen production, the ammonia concentration increased along with increasing salt concentration in the medium. This means that for peak hydrogen production, the C/N ratio decreased with increasing salt content in the medium. The butyrate/acetate (B/A) ratio was higher in proportion to the bio-hydrogen production (r-square: 0.71, p-value: 0.0006). Different concentrations of $Na^+$ and ammonia in the medium also produced diverse microbial communities. Klebsiella sp., Enterobacter sp., and Clostridium sp. were predominant with high bio-hydrogen production, while Lactococcus sp. was found with low bio-hydrogen production.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.825-832
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• 2010

The United Nations Convention on Biological Diversity defines biotechnology as "Any technological application that uses biological systems, dead organisms, or derivatives thereof, to make or modify products or processes for specific use" Biotechnology has made tremendous contributions to improve production efficiency of agriculture during the last century. This article reviews successful examples of application of bio-fermentation in improving swine nutrition efficiency mainly based on the authors'z own research experience. Production of feed grade supplemental amino acids by bio-fermentation allowed nutritionists to formulate accurate feed for optimal lean growth and reduced nitrogen excretion. Recent issues with high feed grain prices caused potential feed quality problems. Bio-fermentation allowed nutritionists to use exogenous supplemental enzymes such as phytase and NSPases in swine diets, thereby improving nutrient utilization and reducing nutrient excretion to the environment. Yeast metabolites are also produced by bio-fermentation and have been repeatedly shown to improve milk production of sows during early lactation even though actual mechanisms are still to be investigated. Bio-fermentation technology also allowed nutritionists to prepare vegetable protein sources with large protein molecules and anti-nutritional factors suitable for feeding newly weaned piglets, as selected microorganisms significantly reduce specific anti-nutritional factors and size of peptides. Preparations of vegetable protein sources suitable for newly weaned pigs will greatly contribute to swine nutrition by providing efficient alternatives to the use of animal protein sources that are often expensive and somewhat against societal preference. Considering the few examples listed above, biotechnology has closely influenced improvement of production efficiency in the swine industry. As we have limited resources to produce meat to satisfy ever-increasing global demands, extensive adaptation of biotechnology to enhance production efficiency should be continued. However, at the same time, wise and careful application of bio-technology should be considered to ensure production of safe food and to meet the expectations of our society.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.62-70
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• 2011

The antibacterial effects of nine lactic acid bacteria (LAB) against Campylobacter jejuni were investigated by using agar gel diffusion and co-culture assays. Some differences were recorded between the inhibition effects measured with these two methods. Only two LAB, Lb. pentosus CWBI B78 and E. faecium THT, exhibited a clear anti- Campylobacter activity in co-culture assay with dehydrated poultry excreta mixed with ground straw (DPE/GS) as the only growth substrate source. It was observed that the supplementation of such medium with a cellulase A complex (Beldem S.A.) enhanced the antimicrobial effect of both LAB strains. The co-culture medium acidification and the C. jejuni were positively correlated with the cellulase A concentration. The antibacterial effect was characterized by the lactic acid production from the homofermentative E. faecium THT and the lactic and acetic acids production from the heterofermentative Lb. pentosus CWBI B78. The antagonistic properties of LAB strains and enzyme combination could be used in strategies aiming at the reduction of Campylobacter prevalence in the poultry production chain and consequently the risk of human infection.

• Environmental Engineering Research
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• v.25 no.1
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• pp.18-28
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• 2020

In this paper the authors provide comparative evaluation of current research that used liquefaction and pyrolysis method for bio-oil production from various types of biomass. This paper review the resources of biomass, composition of biomass, properties of bio-oil from various biomass and also the utilizations of bio-oil in industry. The primary objective of this review article is to gather all recent data about production of bio-oil by using liquefaction and pyrolysis method and their yield and properties from different types of biomass from previous research. Shortage of fossil fuels as well as environmental concern has encouraged governments to focus on renewable energy resources. Biomass is regarded as an alternative to replace fossil fuels. There are several thermo-chemical conversion processes used to transform biomass into useful products, however in this review article the focus has been made on liquefaction and pyrolysis method because the liquid obtained which is known as bio-oil is the main interest in this review article. Bio-oil contains hundreds of chemical compound mainly phenol groups which make it suitable to be used as a replacement for fossil fuels.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2005.10a
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• pp.45-64
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• 2005

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.414-422
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• 2006

Before applying PVA bio-beads to practical biological treatment of nitrate-containing wastewater, their characteristics were examined. PVA bio-beads could steadily produce nitrogen gas from nitrate for 28 batches with 0.04 ml/l/h of the maximum gas production rate; however, the maximum gas production rate dropped remarkably thereafter with apparent deformation of beads. Addition of 2.2% solution containing 1% casamino acid, 1% yeast extract, 0.1% mineral solution, and 0.1% vitamin solution to the culture medium resulted in not only recovery of activity of deactivated beads, but also a higher rate of gas production. Calculation of economic benefit for the use of bio-beads in a long-run operation indicated that reactivation of bio-beads by chemicals had economical advantages over packing new bio-beads in the system. The continuously stirred bioreactor exhibited a satisfactory performance at HRT of 20.0 h. With a 9.5 mg $NO_{3}^{-}N/l/h$ nitrate removal rate, nitrate could completely be removed without nitrite accumulation. The use of PVA bio-beads in nitrate removal appears very promising.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.185-191
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• 2013

Over the past decades, carbon dioxide concentration of the atmosphere of the world has increased significantly, and thereby the greenhouse effect has become a social issue. To solve this problem, new renewable energy sources including solar, hydrogen, geothermal, wind and bio-energy are suggested as alternatives. Among these new energy sources, bio-energy crops are widely introduced and under rapid progress. For example, corn and oilseed rape plants are used for the production of bio-ethanol and bio-diesel, respectively. However, grain prices has increased severely because of the use of corn for bio-ethanol production. Therefore, non-edible switchgrass draws attention as an alternative source for bio-ethanol production in USA. This review describes the shortage of fossil energy and an importance of switchgrass as a bio-energy crop. Also, some characteristics of its major cultivars are introduced including growth habit, total output of biomass yields. Furthermore, biotechnological approaches have been conducted to improve the productivity of switchgrass using tissue culture and genetic transformation.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.380-380
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• 2005

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.965-968
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• 2006

Exogenous S-adenosyl-L-methionine (AdoMet) enhances the production of actinorhodin in Streptomyces coelicolor. Thirty compounds related structurally with AdoMet were tested for their actinorhodin production. The relationships between the structures of the compounds tested and their actinorhodin production were analyzed using computational methods, and the molecules containing both bulky substituents at the C6 position of adenine and the long 5'-alkyl chain of adenosine were predicted to show high actinorhodin production.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.136-136
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• 2017

By-products has been considered lately in Total Mixed Ration (TMR) as an alternative to livestock feed around the world. This is due to the high cost of using forage as feed, less expense in exploring by-products of agriculture origin and environmental concerns with their disposal. However, by-products usually contain contaminants and the production process requires fermentation using a storage and fermentation tank. Animal feed is the start point of the food safety chain in the 'farm-to-fork' model. This necessitated a study to model a protocol that will culminate to safe feed production. Hazard analysis and critical control points (HACCP), a systematic preventive approach to food safety from biological, chemical and physical hazards in production processes that can cause the finished product to be unsafe was explored. Implementation of this model provides a mechanism that ensures product safety is continuously achieved. The entire production process of By-products feed production was evaluated using HACCP wizard software. This includes the plant layout, technical standards, storage and fermentation tank cleansing method, staff assignment, safety control method, and distribution. The potential biological, chemical, and physical hazards that may exist in every step of the production process were identified, and then critical control points (CCPs) were selected. This will ensure the safety of products made from livestock that consumes by-product feed. These includes cheese, milk, beef, etc.