• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.36-43
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• 2015

Excess use of chemical fertilizer causes soil acidification and accumulation of salt, and thus might bring to desertification of soil. To overcome this problem, it needs limited usage of chemical fertilizer and increased usage of natural fertilizer as an alternative. In this study, dry soil-borne Bacillus sp. SHL-3, which was isolated from arid and barren soil, with plant growth promoting activity was isolated for identification and to determine optimal culture condition. A bacterial strain SHL-3 had the IAA productivity ($5.16{\pm}0.10mg\;L^{-1}$), ACC deaminase activity ($0.36{\pm}0.09$ at 51 hours) and siderophore synthesis. It was identified as genus Bacillus sp.. Also, optimal culture condition of SHL-3 were $20^{\circ}C$ and pH 7 in LB medium. Bacillus sp. SHL-3 had up to 4% salt tolerance in the medium. We evaluated the plant growth promotion ability of SHL-3 using yam (Dioscorea japonica Thunb.). As a result, Bacillus sp. SHL-3 was effective on the increase of the shoot length (202.4% increase for 91 days). These results indicate that Bacillus sp. SHL-3 can serve as a promising microbial resource for the biofertilizers of soil.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.339-344
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• 2019

Global sequence alignment in search of similarity or homology favors larger size of the sequence because it keeps looking for more similar section between two sequences in the hope that it adds up scores for matched part in the rest of the sequence. If a substantial size of mismatched section exists in the middle of the sequence, it greatly reduces the total alignment score. In this case a whole sequence would be better to be divided into multiple sections. Overall alignment score over the multiple sections of the sequence would increase as compared to global alignment. This method is called multiple local alignment. In this paper, we implement a multiple local alignment algorithm, an extension of Smith-Waterman algorithm and show the experimental results for the algorithm that is able to search for sub-optimal sequence.

• Journal of the Korean Society of Food Culture
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• v.34 no.3
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• pp.361-368
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• 2019

The purpose of this study was to establish the best optimized extraction condition for the optimal development of fresh maca beverage using low temperature extraction and enzyme treatment. Low temperatures were applied to prevent heat-related nutritional loss during the extraction process. Best extraction conditions were investigated based on the ratio of maca to water, the ratio of enzymes, extraction temperature and time, and agitation. The optimal enzyme conditions were also examined after the treatment of cellulase:pectinase mixture to maintain the original color and flavor, as well as to increase the extraction yield. When cellulase:pectinase was 1:1, the extraction rate ranged from 77.84 to 79.29%. In addition, the best extraction rate was found when maca was mixed with twice volume of water and incubated at $45^{\circ}C$ ($84.05{\pm}0.32%$) with 90 rpm ($87.13{\pm}0.46%$) agitation for 3 hours ($84.73{\pm}0.29%$). Furthermore, sensory evaluation showed a high score in flavor, sweetness, and overall acceptability after adding 3% jujube concentrate into a fresh maca beverage.

• International Journal of Advanced Culture Technology
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• v.10 no.1
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• pp.230-235
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• 2022

This study is to select an optimal object detection algorithm for designing a self-checkout counter to improve the inconvenience of payment systems for products without existing barcodes. To this end, a performance comparison analysis of YOLO v2, Tiny YOLO v2, and the latest YOLO v5 among deep learning-based object detection algorithms was performed to derive results. In this paper, performance comparison was conducted by forming learning data as an example of 'donut' in a bakery store, and the performance result of YOLO v5 was the highest at 96.9% of mAP. Therefore, YOLO v5 was selected as the artificial intelligence object detection algorithm to be applied in this paper. As a result of performance analysis, when the optimal threshold was set for each donut, the precision and reproduction rate of all donuts exceeded 0.85, and the majority of donuts showed excellent recognition performance of 0.90 or more. We expect that the results of this paper will be helpful as the fundamental data for the development of an automatic payment system using AI self-service technology that is highly usable in the non-face-to-face era.

• Journal of Mushroom
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• v.21 no.3
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• pp.110-117
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• 2023

Cordycepin (3'-deoxyadenosine) is a nucleoside analog known for its diverse range of biological activities. This study investigated the effect of different types of sawdust on the production of the bioactive compound cordycepin. The results of the study showed that different types of wood sawdust affected the biosynthesis of cordycepin and a significant increase was observed when the conventional SDB medium was replaced with 1% NaOH treated pine sawdust. To optimize cordycepin production from Paecilomyces tenuipes in a medium containing 1% NaOH-pretreated pine sawdust, we employed Response Surface Methodology (RSM) in its Box-Behnken design (BBD) canonical form. The optimal conditions were determined as follows: a particle size of 109.5111-mesh (140 ㎛) for 1% NaOH-pretreated pine sawdust, an input weight of 21.1679 g/L, and an incubation time of 73.8423 hours. According to our model, this combination is expected to yield a maximum cordycepin content of 896.1428 ㎍/mL. Experimental validation of this prediction was performed using the suggested optimal conditions, resulting in an average cordycepin content of 922.6771 ㎍/mL across three replicates, thus confirming the model's accuracy.

• Journal of the Korean Society of Food Culture
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• v.25 no.2
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• pp.216-224
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• 2010

This study was conducted to aid in the development of the optimal recipe for chocolate with fermented and aged garlic extract (Allium sativum var. pekinense). We added garlic extract in order to increase the nutritional value of the chocolate. The optimal sensory composite recipe was determined, following Central Composites for chocolate with different levels of fermented and aged garlic extract (A) and cream (B), while analysis was performed by Response Surface Methodology, from the date that the sensory evaluation was performed. Ten experimental recipes, including 2 reference points in the composition, were selected. The compositional and functional properties were measured, and physical and sensory values were applied to the mathematical models. Perturbation plots showed the influence of each ingredient on the final product. Measurements showed significant values in lightness, sweetness, pH, hardness and cohesiveness, while sensory measurements showed significant values in color, texture, sourness, bitterness and overall quality. The optimum formulations were calculated by numerical and graphical methods, as being 34.61g fermented and aged garlic extract and 72.68g cream for each 200g chocolate. As well it was revealed that the aptitude of chocolate was more influenced by fermented garlic extract than it was by cream.

• Journal of Ecology and Environment
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• v.48 no.2
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• pp.128-136
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• 2024

Background: Prasiola japonica is a freshwater green algae species that can only be seen in Korea and Japan. The various conditions necessary for its growth and reproduction have not been fully elucidated. Therefore, in this study, we aimed to investigate conditions related to the growth and reproduction of P. japonica for the purpose of conserving and producing this species. We first examined differences in growth according to various conditions in different habitats to understand the growth environment of P. japonica. Results: The experimental results revealed that the optimal temperature for growth and reproduction of P. japonica was between 10℃-15℃, and the optimal light intensity was 1,000-1,500 lux. Furthermore, when Provasoli enriched seawater with iodine (PESI) agar was used, the growth of P. japonica was found to be at least 1.5-8 times greater than that of the general Sohan Valley water sample, and it also showed 2-4.5 faster growth rate to reach 30 ㎛. These results emphasize the importance of PESI agar in the culture of P. japonica, and are expected to be helpful in suggesting ways to utilize and conserve P. japonica resources. Conclusions: Through these research findings, we suggest new methods for conserving and producing P. japonica, highlight the importance of preserving the P. japonica ecosystem, and explore ways to utilize P. japonica resources. This research promotes the understanding and protection of P. japonica resources in Korea and beyond, and underscores the need for further research and conservation efforts.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.509-518
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• 2010

Purpose: Major drawbacks of conventional bone marrow stromal cells (BSCs) transplantation method are mainly caused by direct transplanted cell to host cell interactions. We hypothesized that separation of the transplanted cells by a microporous membrane might inhibit most of the potential adverse effects and induce superior effect. The purpose of the study is to determine the optimal condition of the microporous membrane. Methods: First, BSCs were placed in polyethylene terephthalate (PET) transwell inserts with 3, 8, or $12{\mu}m$ pore size, and cultured in 24 well culture plates. After 5 days, bottoms of the plates were observed for presence of attached BSCs in monolayer and cell numbers were evaluated. Second, BSCs were placed PET, polycarbonate (PCT), and mixed cellulose esters (MCE) transwell inserts with 3 and $8{\mu}m$ pore size, and cultured in 24 well culture plates. After 3 days, the supernatants of the media left in culture plate were analyzed for collagen, vascular endothelial growth factor (VEGF), platelet derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF). Third, BSCs were placed in 15% and 70% of the PET membrane with $3{\mu}m$ pore size. All the experimental conditions and methods were same as the second study. Results: The optimal pore sizes to prevent BSC leakage were $3{\mu}m$ and $8{\mu}m$. The amounts of type I collagen and three growth factors tested did not show significant differences among PET, PCT, and MCE groups. However, the collagen, VEGF, and bFGF levels were much higher in the high (70%) density group than in the low (15%) density group. Conclusion: This study revealed that the optimal pore size of membrane to prevent direct BSC to recipient cell contact is in between $3{\mu}m$ and $8{\mu}m$. Membrane materials and pore sizes do not influence the collagen and growth factor passage through the membrane. The most striking factor for collagen and growth factor transport is pore density of the membrane.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.363-370
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• 1992

Microorganisms capable of accumulating poly-p-hydroxybutyric acid(PHB) were isolated from soil by enrichment culture technique. Among them, the strain designated as FL-027 had high PHB productivity and was identified as Alcaligenes. The optimal medium composition for cell growth was 8.0 $g/\ell$ of fructose and 3.0 $g/\ell$ of $(NH_4)_2S0_4$, equivalent to C/N ratio 5.04 at pH 7.0 and $30^{\circ}C$. To investigate the optimal conditions for the PHB accumulation, we divided the process into two stages; the first stage for the growth of the cell in nutrient-rich medium and the second stage for the PHB accumulation in nutrient-deficiency medium. The optimal conditions for PHB accumulation were 8.0 $g/\ell$ of fructose and 0.25 $g/\ell$ of $(NH_4)_2S0_4$, equivalent to C/N ratio 60 at pH 6.5 and $30^{\circ}C$. PHB accumulation was stimulated by deficiency of nutrients such as $NH_4^+$, $Ca^{2+}$, $SO_4^{2+}$ in medium. Among them. $NH_4^+$ deficiency was chosen because of its effectiveness. We found the inhibition of cell growth by fructose in batch culture. In order to keep the fructose concentration at an optimal level, intermittent feeding fed-batch culture was employed, and the cell concentration as high as 10.83 $g/\ell$ whose PHB content was responsible for 43% of the dry cell weight. The purified PHB was identified as homopolymer of 3-hydroxybutyric acid by using IR and $^1H-NMR$.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.895-902
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• 2014

Bacterial cellulose (BC) has played important role as new functional material for food industry and industrial products based on its unique properties. The interest in BC from static cultures has increased steadily in recent years because of its potential for use in medicine and cosmetics. In this study, we investigated culture condition for BC production by Acetobacter sp. F15 in static culture. The strain F15, which was isolated from decayed fruit, was selected on the basis of BC thickness. The optimal medium compositions for BC production were glucose 7%, soytone 12%, $K_2HPO_4$ 0.2%, $NaH_2PO_4{\cdot}_2H_2O$ 0.2%, lactic acid 0.05% and ethanol 0.3%, respectively. The strain F15 was able to produce BC at $26^{\circ}C-36^{\circ}C$ with a maximum at $32^{\circ}C$. BC production occurred at pH 4.5-8 with a maximum at pH 6.5. Under these conditions, a maximum BC thickness of 12.15 mm was achieved after 9 days of cultivation; this value was about 2.3-fold higher than the thickness in basic medium. Scanning electron micrographs showed that BC from the optimal medium was more compact than plant cellulose and was reticulated structure consisting of ultrafine cellulose fibrils. BC from the optimal medium was found to be of cellulose type I, the same as typical native cellulose.