• Korean Journal of Microbiology
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• v.48 no.1
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• pp.16-21
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• 2012

Since many pesticides cause various health and environmental problems, alternative measures to replace them are needed, and the bacteria producing the antifungal substances can be one of them. In this study, several rhizobacteria were isolated and their antifungal activities against some important plant pathogenic fungi were examined. Pseudomonas otitidis TK1 and Paenibacillus peoriae RhAn32 inhibited the growth of Fusarium oxysporum f. sp. niveum and F. oxysporum f. sp. lycopersici by 49.8% and 45.6%, and 45.1% and 48.3%, respectively compared to those of the control. P. peoriae RhAn32 also decreased the growth of F. oxysporum f. sp. raphani by 37.5%. This growth inhibition might be due to the production of antifungal substances, such as siderophore, hydrogen cyanide and chitinase, which were produced by these rhizobacteria. P. otitidis TK1 also produced plant growth hormones indole acetic acid and indole butyric acid at $293.41{\mu}g/mg$ protein and $418.53{\mu}g/mg$ protein, respectively. When P. otitidis TK1 and B. cereus TK2 were inoculated together with F. oxysporum f. sp. lycopersici to the 4 weeks grown tomato seedlings and incubated additional 8 weeks, the stem lengths of tomato increased up to 45.7% and 55.3% and root lengths were raised to 64.9% and 60.8%, respectively than those of the control group. The wet weights increased by 118% and 182%, respectively compared to the control group.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.520-526
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• 2007

To select submerged macrophytes to suppress growth of Microcystis aeruginosa through releasing allelochemicals, we conducted growth experiments with water from patches of submerged macrophytes and with aqueous extracts of those submerged macrophytes. In the first experiment, growth rates of M. aeruginosa decreased as biomass of Myriophyllum spicatum and Hydrilla verticillata increased. In the second experiment, M. aeruginosa showed approximately 50% growth reduction with extracts from M. spicatum and 24% reduction with extracts from Ottelia alismoides. Both M. aeruginosa growth experiments with water and plant extracts suggest that M. spicatum would be the best candidate to reduce M. aeruginosa growth.

• Journal of Mushroom
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• v.4 no.3
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• pp.122-127
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• 2006

This study was carried out to investigate the mycelial growth and density of A. auricula treated four kinds of substances L-citrulline, L-carnitine, Senna, Garcinia cambogia made from 10, 100, 500, 1000, 1500, 2000 times solutions respectively. Senna all treatments made from 10, 100, 500, 1000, 1500, 2000 times solutions are available for mycelial growth and density than control. Senna treatment made from 100 times solution of them is the best. L-citrulline treatment made from 500 times solution grew more much 7.86mm for 15 days than control, also it was optimal. L-carnitine treatment made from 100 times solution grew more much 3.4mm for 15 days than control, also it was optimal. Garcinia cambogia all treatments made from 10, 100, 500, 1000, 1500, 2000 times solutions were not available for mycelial growth and density than control. But Garcinia cambogia treatment made from 1000 times solution of them was similar to control. Accordingly, these solutions like that were effective to mycelial growth and density than control.

• Journal of Sericultural and Entomological Science
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• v.30 no.1
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• pp.1-7
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• 1988

Flower buds of the mulberry(Morus alba L., Morus bombycis Koidz.) were cultured under different conditions such as basal media, and various concentrations of plant growth substances. Effects of the culture conditions on growth of the buds and organ regeneration were investigated and the result obtained are as follows: Murashige and Skoog(M.S.) medium was more effective on budding and growth of female(Keomseolppong) and male(Kaeryangppong) flower buds isolated directly from branches, compared to Greshoff & Doy(G.D.) and Wolter & Skog(W.S.) media. The growth of the female buds was promoted at higher concetration of benzyl amino purine(BAP) i.e., 2.0ppm. The female and male buds cultured after cuuting for seven days showed better growth than those without cutting treatment. The females and the males bloomed to form healthy stigmas and anthers, respectively, when cultured on M.S. media containing high Kinetin with low concentration of indole acetic acid(IAA).

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.226-231
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• 2010

We aimed at the monitoring medroxyprogesterone acetate (MPA) residue amount in meats and confirmed the safety of its residue in meats. Optimized condition for analytical and instrumental methods was obtained by method validation. The limit of detection (LOD) and limit of quantification (LOQ) were validated at 1.5 and 5.0 ug/kg, respectively. The calibration curve showed good linearity ($r^2$ = 0.9968) within the concentration range of 5.0~50.0 ug/kg. We selected progesterone-d9 for internal standard, The recoveries in fortified meat ranged from 67.5 to 109.56% at the 3 spiking levels. As the regulation of MPA analysis method used by LC-MS/MS on other products have established. We selected 3 species of farm stock products (cattle, pig, chicken) and purchased at the markets of seven major cities. The total 196 of meat including 46 of domestic beef, 43 of import beef, 60 of domestic pork, 12 of import pork and 35 of domestic chicken. No residue of synthetic growth hormones were detected in cattle, pig and chicken samples tested.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.21-30
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• 1975

The purpose of this paper is to elucidate physiologically the cause of the hastening germination of dormant Taxus cuspidata seeds by stratification. During the stratification the exchange of chemical substances such as sugar, protein, starch and fat were observed, and growth promoting and inhibiting substances were extracted and seperated from seeds by the conventional chromatographic method with coleoptile straight-growth test. An intensive investigation was made on the balance between the promoters and inhibitors. consequently, it was confirmed that germination of seeds was accelerated with exchange of chemical substances by stratification. The results obtained may be summarized as follows: 1. During the stratification growth promoters were increased and growth inhibitors were decreased rapidly in the endosperm of seeds. Thus, it was presumed that hastening germination was controlled by balace between the promoters and inhibitors from November to next March after a year's stratification. On the other hand growth promoters were almost constant and growth inhibitors were decreased rapidly in the seed coats, and it was presumed that hastening germination was influenced by exchange of inhibitors more than by that of promoters. 2. As a results of germination test of lettuce seeds, it was generalized that hastening germination was controlled by a decreased amount of growth inhibitors more than by an increased amount of promoters. 3. During the stratification sugar and crude protein contents were increased gradully with moisture content, while starch and crude fat were decreased in endosperm of seeds. So it was assumed that the exchange of these chemical substances was closely related to the germination of seeds.

• Journal of Sericultural and Entomological Science
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• v.23 no.1
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• pp.1-31
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• 1981

Rootability of the hardwood cuttings of mulberry was related not only histological characteristics but dependent on biochemical properties. In this connection, the characteristics of the hardwood cuttings were histologically observed and the growth substances produced by the cuttings were also identified by means of mung bean bioassay. Amino acid, carbohydrate, nucleic acid contents, and the C/N ratio were also analysed. The results are summarized as follows. 1. There were differences in rootability of cuttings between mulberry species and varieties Among the three mulberry species tested, Morus Lhou Koidz. showed the highest rootability while M. bombycis showed the lowest one. In varietal differences in rootability, it was shown that the varieties could be grouped according to rootability: high varieties(above 80%), medium(41~79%), and low(below 40%). The higher varieties were Kemmochi, Nakamaki, Kosen, and Wusuba roso. 2. The histological characteristic of the hardwood cuttings most closely related to rootability was cell layer arrangement in the sclerenchyma tissue. The lower rootability varieties developed two or three overlapping cell layers in the bark tissue and in the higher rootability varieties they were scattered over the primary cortex. 3. In the higher rootability varieties, there was a positive correlation between the development of root primodia and rootability of the hardwood cuttings. It was also shown that there was a close relationship between the size of primodia and the surface area of the lenticel with rootability of the cuttings. 4. Effect of growth substances extracted from the hardwood cuttings were determined by mung bean bioassay. The higher rootability varieties usually showed higher activities of the growth substances, in contrast the lower rootability varieties showed higher activities of the inhibitory substances. 5. It was evident that the substance separated by paper chromatography was identified as indole acetic acid with $R_f$ value ranging from 0.3 to 0.5. The other substances detected at a $R_f$ value ranging from 0.8 to 1.0 and origin to 0.1 were also responsible for rooting. 6. There exists a quantitatively different distribution of growth substances in a synergistic system in the tissues of cuttings, and the balance between growth and inhibitory substances gives rise to the development of rooting. Particularly, no descent of the substances from winter buds resulted in no rooting of cuttings but these substances were produced a week after planting in a warm environment. 7. It was shown that there were positive correlations between carbohydrate ($r=0.72^*$) and total sugar ($r=0.67^*$) and rootability, respectively, but there were negative correlations between reducing sugars ($r=-0.75^*$) and rootability. 8. High C/N ratio gave rise to high rootability($r=0.67^*$). The latter therefore depended on high amount of carbohydrate rather than nitrogen in the cuttings. 9. The content of RNA and DNA in the cuttings was not changed for upto two weeks after the cuttings were planted. Then an increase in RNA content took place in only the high rootability varieties. 10. There were quantitative and qualitative differences in the compositions of the amino acids between the high rootability varieties and the low rootability varieties. More aspartic acid and cystine were found in the higher rootability varieties than in the low rootability varieties.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.193-204
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• 2020

This experiment was conducted to study the effect of organic fertilizer on the growth of Peucedanum japonicum Thunberg and the change of soil chemical characteristics. The organic matter contents of coffee sludge and dried food waste powder were 44.26 and 51.18%, respectively. These values exceed the organic matter content of organic fertilizers recommended by the Rural Development Administration (RDA) of South Korea by more than 30%. Accordingly, they indicate the possibility of their use as organic fertilizers. The results from the analysis of soil properties after cultivation showed that the organic matter content of coffee sludge amended soils was two-fold higher than that of dried food waste powder amended soils. However, the content of available phosphorus was two times lower in the coffee sludge amendments. It is expected that the dried food waste powder was actively used to decompose organic substances, and that phosphoric acid was added by the soil microorganisms used to decompose organic substances. In terms of Peucedanum japonicum Thunberg growth, leaf discoloration was observed for all treatments except with the standard rate of dried food waste powder. The standard rate of dried food waste powder also produced relatively better results than other treatments with regard to other growth characteristics such as root length (34.08 cm), root diameter (0.78 cm), and fresh root weight (4.77 g plant^-1). Therefore, the standard rate of dried food waste powder produced better results than other treatments and can be used as an organic fertilizer in the growth of Peucedanum japonicum Thunberg.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.6
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• pp.878-888
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• 2023

Growth responses of Chlorella vulgaris exposed to different light intensities and wavelengths of light-emitting diodes (LEDs) were investigated. C. vulgaris was cultured under red LED (650 nm), blue LED (450 nm), green LED (520 nm), and fluorescent lamps (three wavelengths, control). The maximum growth rates (µ_max) of C. vulgaris were highest under the blue LED, followed by the red LED, green LED, and fluorescent lamps. The low compensation photon flux density (I₀) and low half-saturation constants (K_s) were observed in C. vulgaris cultured under the red LED, indicating that high C. vulgaris growth is closely related to the low light intensity of the red LED suggesting that the red LED can be useful for the biomass production of C. vulgaris. Furthermore, it was observed that under the blue LED during the stationary phase, there was an increase in useful bioactive substances, such as proteins and lipids, which are beneficial for biomass production. In conclusion, the red LED is an economical light source that can enhance cell density, and the blue LED is effective in promoting valuable intracellular substances.

• Journal of Soil and Groundwater Environment
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• v.29 no.1
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• pp.51-62
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• 2024

A study was performed to investigate the positive impacts of humic substances (HS) on the growth of green barley, a type of green manure plant. The study was conducted in a pot culture using two different types of reclaimed soils that had been treated by land farming (DDC) and thermal desorption (YJ) methods, respectively. The experimental conditions consisted of three treatments: plant only (P), plant plus 2% HS, and no plant (control). After 89 days of culture in a controlled growth chamber, the growth of spring barley and activity of seven soil enzymes were measured. The results indicated that the addition of HS had a substantial (p<0.10) positive effect on shoot biomass in both types of soil. Furthermore, the addition of HS notably (p<0.05) enhanced all seven soil enzyme activities in both soils. Both the aboveground and belowground parts of barley plants were returned to soil and aged for 10 weeks in the same growth chamber, which resulted in notable enhancement in soil health indicators. These improvements included an increase in organic matter, a drop in bulk density, and an increase in the activity of seven different soil enzymes. When lentil seeds were planted in the aged soils, the development of the seedlings was more vigorous than that in the control in both soils, although allelopathy of barley suppressed lentil germination in soil with pH 7.0 but not in soil with pH 8.5.