• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.58-62
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• 1993

The effects of carbohydrate sources(sucrose, glucose) and ratio of ammonia to nitrate on essential oil production and its com- positions in the callus culture of Mentha piperita L. were studied. An ammonia : nitrate ratio of 1 :2 was more effective for essential oil production regardless of the media used ; Lin-Staba(LS) and modify Murashige-Skoog(MS) medium. Menthol biosynthesis was enhanced when ratio of ammonia to nitrate was 1 :3 in the LS medium while the ratio was 1 :2 in the MS medium. Lower sucrose concentration(20g /1 ) was much better than higher sucrose concentration(30g /1) for both oil and menthol biosynthesis in the LS medium but higher sucrose concentration(30g /1) was more effective for those in the MS medium. When sucrose was replaced with glucose, menthol biosynthesis was sharply decreased or absent regardless of media used.

• Journal of Environmental Science International
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• v.29 no.8
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• pp.819-826
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• 2020

Production of Bacterial Cellulose (BC) by Gluconacetobacter sp. A5 was studied in shaken culture using different cost-effective carbon sources and its structural and mechanical properties were evaluated. Glycerol showed the highest level (7.26 g/l) of BC production, which was about three times higher than the yield in glucose medium. BC production depended not only on the decrease in pH, but also on the ability of Gluconacetobacter sp. A5 to synthesize glucose from different carbon sources and then polymerize it into BC. All BC produced from different carbon sources exhibited a three-dimensional reticulated structure consisting of ultrafine cellulose fibriles. Carbon sources did not significantly change the microfibrile structure of the resulting BC. BC produced from glucose medium had the lowest water-holding capacity, while BC from molasses medium had the highest. XRD data revealed that all BC were cellulose type I, the same as typical native cellulose. The crystalline strength of BC produced in glucose medium was the highest, and that in molasses medium was the lowest. Our results suggest that glycerol could be a potential low-cost substrate for BC production, leading to the reduction in the production cost, and also to produce BC with different mechanical properties by selecting appropriate carbon source.

• Journal of Korean society of Dental Hygiene
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• v.8 no.3
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• pp.139-148
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• 2008

A fluorine solution was used to measure the growth of S.mutans and the pH changes were also measured in order to find an effective and preventative dentistry lab within a limited time for the dental hygiene department curriculum and the following results were obtained. 1. In the growth comparison of S.mutans, the culture medium of the experiment group with fluorine weighed 0.3g and the culture medium with no fluorine weighed 0.5g, which shows that the growth rate of S.mutans is significantly decreased in the culture medium with the fluorine. 2. The pH7.8 of the culture medium was not nearly changed; it became 7.0 after culturing with fluoride, however the pH was significantly decreased to 3 in the culture medium that had no fluorine. 3. Since it has been proven that the fluorine can control the growth of germs, it is believed that the effect of fluorine as a cavity preventative should be emphasized to students and in addition, it will help students transmit the effect of fluoride to their patients since this knowledge has been acquired through practice. 4. It is considered that this is a simple test protocol providing effective results in the microorganism and preventive dentistry lab within a limited time and furthermore, it will furnish the students of dental hygiene with comprehensive accessibility to dental hygiene curriculum.

• Food Science and Preservation
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• v.23 no.6
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• pp.759-764
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• 2016

This purpose of this study was to determine the best enrichment medium for rejuvenating and recovering Salmonella placed in cold temperature prior to the employment of the gold biosensor combined with a light microscopic imaging system. A mixture of nalidixic-resistant Salmonella Typhimurium and Enteritidis were inoculated onto chicken (1,000 CFU/chicken). After cold injury at $4^{\circ}C$ for 24 hr, Salmonella on chicken was enriched for 6 hr with six non-selective media including buffered peptone water broth, lactose broth, brain heart infusion broth (BHI), universal pre-enrichment broth, nutrient broth, and tryptic soy broth, and five selective media including brilliant green broth (BG), rappaport-vassiliadis R10 broth, selenite cystine broth, selenite broth, and tetrathionate brilliant green broth (TBG) for the comparison of Salmonella growth. Various concentrations of Salmonella (10, 50, 100, 500, and 1,000 CFU/chicken) were then enriched for 6 hr in both BHI and BG media to select the best media. BHI was selected as the most effective non-selective enrichment medium, while BG was selected as the most effective selective enrichment medium. Finally, BHI medium was selected as the most efficient enrichment medium for Salmonella growth injured from cold temperature during processing or storage.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.184-190
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• 1993

This study was carried out to investigate the appropriate medium and constitutionof growth regulators for somatic embryogenesis for development of rapid mass propagation system via somatic embrygenesis in Rehmennia glutinosa. Embryogenic callus formation from leaf explant was more effective when 4mg / l BA with 0.5mg / l NAA than that of treated with only auxins or cytokinins. LS medium was suitable for embryogenic callus formation. LS medium with 4mg / l BA with 0.5mg / l NAA was effective for the maintenance and proliferation of embryogenic callus. In suspension culture, addition of 1mg / l BA to LS medium was proper for somatic embryogenesis. The highest rate of shoot developement form cotyledon stage embryo was obtained in 1/2 LS medium and plantlet survived by 75% after transplanted to the soil. after 4 weeks.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.44-50
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• 1994

This study was carried out to select the appropriate medium(especially, carbon and nitrogen source ) for somatic embryogenesis in order to develop the rapid mass production system in suspension culture of chuanxiang Hort. Suitable medium for somatic embryo formation was MS medium. The half strength MS medium was effective for somatic embryo development. Sucrose was the most effective carbon source for somatic embryo formation, however, production of somatic embryos was reduced at higher concentration of sucrose. Effects of suger was the same as sucrose. Somatic embryo formation was higher as the decrease of $NH_{4}NO_3$, and optimum ratio of $KNO_3\;:\;NH_4NO_3$ was 825 : 238mg /1. Regenerated plant was obtained in MS basal medium and survival late of plantlet was 60-70% after transplanted directly to the vermiculite.

• Applied Biological Chemistry
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• v.2
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• pp.9-14
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• 1961

The formation of sulfide from sulfate has been discussed from the thermodynamic principles. No mechanism of the reaction has been presented. From the stoichiometric and Nernst equations for the conversion of sulfate into sulfide, it was concluded that the formation of sulfide from sulfate can take place more readily if pH of a medium is low. The difficulty of this conversion increases with increasing pH. As pH of a medium increases, the degree of dissociation of H₂S into S= increases and this, in turn, renders the chance of precipitation of sulfide as FeS easier. Higher the pH of a soil or medium, greater is the S= concentration. The concentration of ferrous ion required to remove dissolved sulfide in a medium by forming insoluble FeS decreases with increasing pH. From the theory it was pointed out that an application of lime and iron rich foreign substances to a soil may be effective in causing the removal of dissolved sulfide from solution.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.218-223
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• 1997

For the utilization of animal blood produced in slaughter for the cultivation of lactic acid bacteria, the nitrogen sources in a complex(MRS) medium were replaced by blood plasma proteins. Focusing the purpose on the industrial production of a probiotics, the hydrolytic activities of three industrially applicable proteases were compared for the effective digestion of the proteins, and Alcalase(the product of Novo Nordisk) was selected with comparatively high activity. The growth of Streptococcus thermophilus KCCM12020 was best among the four strains of lactic acid bacteria tested. With Alcalase-digested proteins in the medium, the growth rates and the final cell concentrations were higher than those with non-digested proteins. The cell mass produced in the medium containing blood proteins as nitrogen sources, $2.5{\times}10^9$ CFU/ml, was significantly high and about 70% of that in MRS medium, showing a great possibility for the utilization of animal blood proteins as economic nitrogen sources in the production of cell mass of lactic acid bacteria.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.3
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• pp.66-73
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• 2003

Alkaline cellulolytic enzymes are prepared from Coprinus cinereus 2249. Recovery method of enzyme protein from cultured medium and effect factors on enzyme activity of protein were investigated. The results could summarized as follows, \circled1 Amount of enzyme protein from cultured medium was highest in incubation with shaking and addition of skim milk. \circled2 Protein from cultured medium was alkaline enzymatic protein which shows the highest activity at pH 9.0. \circled3 The most effective recovery method of enzyme protein was the precipitation of protein by addition of cultured medium of protein in ethanol. \circled4 The enzyme activity was enhanced by tween-80 and decreased with $Al_2(SO_4)_3$, $H_2O_2$et al, and was little changed with metal ions except $Hg^{++}$.

• Korean Journal of Microbiology
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• v.11 no.2
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• pp.51-58
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• 1973

Three kinds of organic matter such as glucose, oxalic acid, and ethanol were added to the media(N-free or $NO_{3}$-riched) and their effects on the nitrogen fixation of Nostoc pruniforme were measured by manometric technique through the experiments in vivo. 1) The organic matters used in this experiments showed effective results as a role of substrate for the fixation of atmospheric nitrogen. 2) In the nitrogen-free medium treated with the both of flucose nad ethanol, the highest nitrogen uptakes were detected in the treated of low concentrations (glucose ; 0.1%, 0.5%, ethanol : 0.1%, 0.5%). On the contrary, the highest nitrogen uptakes in $NO_{3}$-riched medium were measured at the treated of high concentrations (glucose ; 2%, 1%, ethanol ; 1.5%, 1.0%). 3) The highest nitrogen uptakes in N-free medium treated with oxalic acid were measured at the concentration of 2% and 1%, respectively. In the medium of $NO_{3}$-riched, the nitrogen uptakes were in the opposite directions.