• Journal of the Korean Society of Food Culture
• /
• v.11 no.4
• /
• pp.497-506
• /
• 1996

Fermentation characteristics and quality changes of the typical Korean traditional alcoholic beverages (Kwahaju, Sokokju, Baikhaju, Samhaeju and Hosanchun) were investigated during fermentation and after aging, respectively. They were prepared by their own brewing methods with respect to the same contents of rice and Nuruk (Korean-style bran koji). The consumed total sugar content of the alcoholic beverages (Sokokju, Baikhaju, Samhaeju and Hosanchun) which were brewed with the multiple input steps of seed mash and raw material (ABMIS) was higher than that of the alcoholic beverage (Kwahaju) which was brewed with the single input step (ABSIS). The pH values of all the beverages were similar and were ranged from 3.2 to 3.6. The acidity of ABMIS were lower than that of ABSIS, but alcohol concentration of ABMIS were higher. The fermentation period of the alcoholic beverages with triple input steps was the longest among them. The inner temperature and microbial growth in all the beverages increased at each of input steps of the raw materials. Fusel oil content of ABMIS was lower than that of ABSIS. Major components of the fusel oil were iso-amyl alcohol, iso-butanol, n-propanol, ethyl acetate and acetaldehyde, and its minor components were methanol and n-butanol. The results on quality changes of the alcoholic beverages after aging showed increase of alcohol in ABMIS, but decrease of sugar and acidity. Fusel oil contents of Kwahaju and Samhaeju decreased to be ranged from 3.1% to 13.9% after aging, but those of Sokokju, Baikhaju and Hosanchun increased to be ranged from 10.9% to 23.0%. Sensory evaluation of ABMIS showed better scores than that of ABSIS. It was suggested that the brewing method with multiple input steps of seed mash and raw material was one of the methods to increase fermentation efficiency for brewing the Korean traditional alcoholic beverages.

• Journal of the Korean Society of Food Culture
• /
• v.11 no.5
• /
• pp.711-719
• /
• 1996

Fermentation characteristics of kwahaju (a typical Korean traditional alcoholic beverage) base were investigated during fermentation with different contents of nuruk (Korean-style bran koji) extract. The nuruk extract which was prepared by incubating the mixture of nuruk powder and water at $25^{\circ}C$ overnight and by filtering it was used to be 0.6%, 2.7%, 5% and 10% (v/v). Total and reducing sugar contents as well as acidity of the kwahaju base with 0.6% nuruk extract were higher than those with 2.7%, 5% and 10% at the fermentation end. Final pH values of all the base samples were ranged from 3.3 to 4.1. Alcohol concentrations of the base samples with 2.7%, 5% and 10% nuruk extract were higher than those with 0.6%. Microbial growth rate was great and inner temperature was high in the sample with high content of nuruk extract, but fermentation period was short. Total sugar consumption and alcohol production increased as the content of nuruk extract increased, but total acid production decreased. The base sample with 10% nuruk extract showed the most excellent fermentation efficiency. Fusel oil content of the base sample with 2.7% nuruk extract was the highest (457.3 ppm), and those wity 5% and 10% nuruk extract were 438.9 ppm and 442.6 ppm, respectively. The sample with 0.6% nuruk extract had the lowest content (409.5 ppm). Sensory evaluation of both the kwahaju base and kwahaju mix with 25% and 40% alcohol by adding soju (Korean distilled liquor) showed that the base with 2.7% nuruk extract had the highest score, and that the kwahaju mix with 25% alcohol had higher score than that with 40%. The sensory results on overall desirability were consistent to those on color and alcohol concentration, and it turned out that the two factors were important to make kwahaju.

• Current Research on Agriculture and Life Sciences
• /
• v.20
• /
• pp.77-82
• /
• 2002

This study was carried out in order to produce useful material for the forest multiple use and forest protection by physico-chemical soil analysis of studied area in Sokwang-ri Forest Genetic Resource Protection Forest which was divided into in standard plots include Tricholoma matsutake and Sarcodon aspratus production forest. The result of physico-chemical soil analysis represented as following. The soil type of T. matsutake production forest was Dry brown forest soil(B1), while on the other hand the soil type of S. aspratus production forest was Moderately moist brown forest soil(B3). Between T. matsutake and S. aspratus production forest did not result in significant changes in soil pH(5.22-5.60) and soil depth(47cm), but available phosphorus, carbon, and nitrogen contents were different results. CN ratio of the fairy ring of T. matsutake was quite lower than that in S. aspratus production forests, which indicated that T. matsutake production forest was built up in the relatively immature soils which contain little organic matter. Generally, it was predicted that Pinus densiflora for. erecta forest succeeded to deciduous tree forest in stable soil environments. To conserve these T. matsutake and S. aspratus production forest, the contents of available phosphorous and exchangeable cation should be increased by continuous soil environment management and it should be established the secondary growth forests of old aged Pinus densiflora for. erecta trees as soon as possible.

• Journal of the Korean institute of surface engineering
• /
• v.37 no.5
• /
• pp.253-262
• /
• 2004

Calcareous deposits are the consequence of pH increase of the electrolyte adjacent to metal surface affected by cathodic current in seawater. It obviously has several advantages over conventional coatings, since the calcareous deposit coating is formed from coating (Mg$^{2+}$, $Ca^{2+}$) naturally existing in seawater. In consideration of this respect, environment friendly calcareous deposit films were formed by an electro deposition technique on steel substrates submerged in 48$^{\circ}C$ natural seawater. And the influence of current density, coating time and attachment of steel mesh on composition ratio, structure and morphology of the electrodeposited films were investigated by Scanning Electron Microscopy(SEM), Energy Dispersive Spectroscopy(EDS) and X-Ray Diffractor(XRD), respectively. Accordingly, this study provides a better understanding of the composition between the growth of $Mg(OH)_2$ and $CaCO_3$ during the formation of electro deposit films on steel substrate under cathodically electrodeposition in $48^{\circ}C$ natural seawater. The Mg compositions, in general, are getting decreased regardless of current density but Ca compositions are getting increased as electrodeposition time runs. That is, $Mg(OH)_2$ compounds of brucite structure shaped as flat type is formed at the initial stage of electrodeposition, but CaCO$_3$ compounds of aragonite structure shaped as flower type is formed in large scale. Besides, $Mg(OH)_2$ compounds were much formed at 5 A/$\m^2$ environment condition compared to the 3 A/$\m^2$ and 4 A/$\m^2$ environment conditions. This is because that OH- which was comparatively largely generated at the metal surface is preferably combined with $Mg^{2+}$TEX>.

• Mycobiology
• /
• v.47 no.3
• /
• pp.301-307
• /
• 2019

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

• Korean Journal of Plant Resources
• /
• v.17 no.3
• /
• pp.331-338
• /
• 2004

This study was conducted to obtain the virus free plants through meristem culture of carnation (Dianthus caryophillus). Four cultivars (Roland, Desio, Casha, Giant Gipsy) were collected for materials. The apical meristem 0.3-0.5mm in size was cultured on MS medium containing 3% sucrose, 0.9% agar at pH 5.8 with various plant growth regulators for 7 weeks. Among the cultivars, Giant Gipsy had a better response than other cultivars in shoot formation and reduced vitrification. Callus induction and shoot formation from the meristem culture were influenced by the various kinds of cytokine. Kinetin supplement was the most effective for shoot formation and NAA addition was good for callus induction among the treatments. Total 115 plantlets derived from apical meristem culture were checked for CarMV and CarRSV infection by ELISA test. Among them, 40 plantlets (34.8%) were infected with CarMV but not detected for CarRSV.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.3
• /
• pp.473-478
• /
• 2011

A wide diversity of liquid fertilizers and composts produced from the livestock manure in Korea is commonly applied to agricultural lands as an alternative of chemical fertilizers. However, their effects on the crop production and environmental impacts are still vague. The current study was conducted to understand the effects of the pig manure-based liquid fertilizer on the growth of Zea mays L. and soil properties. Four different liquid fertilizers were treated to each cultivated upland plot located in Gyeong-gi province, Korea while no fertilizer (control A) and a chemical fertilizer (control B) were treated to separate plots for comparison. The liquid fertilizer treatment did not make a significant difference in the fresh weight of Zea mays L. compared to the controls. This is probably due to the nutrient residues carried over from the last year fertilization. Electric conductivity (EC) and organic matter contents in soils were increased right after the liquid fertilizer treatments compared to the controls. However, soil pH was maintained as the same as the level of control A. A long-term effect of the continuous treatment of the manure based liquid fertilizer will be carried out in the successive study.

• Journal of Microbiology and Biotechnology
• /
• v.29 no.6
• /
• pp.923-932
• /
• 2019

Current strategies of strain improvement processes are mainly focused on enhancing the synthetic pathways of the products. However, excessive metabolic flux often creates metabolic imbalances, which lead to growth retardation and ultimately limit the yield of the product. To solve this problem, we applied a dynamic regulation strategy to produce $\text\tiny{L}$-phenylalanine ($\text\tiny{L}$-Phe) in Escherichia coli. First, we constructed a series of Phe-induced promoters that exhibited different strengths through modification of the promoter region of tyrP. Then, two engineered promoters were separately introduced into a Phe-producing strain xllp1 to dynamically control the expression level of one pathway enzyme AroK. Batch fermentation results of the strain xllp3 showed that the titer of Phe reached 61.3 g/l at 48 h, representing a titer of 1.36-fold of the strain xllp1 (45.0 g/l). Moreover, the $\text\tiny{L}$-Phe yields on glucose of xllp3 (0.22 g/g) were also greatly improved, with an increase of 1.22-fold in comparison with the xllp1 (0.18 g/g). In summary, we successfully improved the titer of Phe by using dynamic regulation of one key enzyme and this strategy can be applied for improving the performance of strains producing other aromatic amino acids and derived compounds.

• Journal of Mushroom
• /
• v.16 no.4
• /
• pp.267-271
• /
• 2018

This study was carried out to select the suitable for bag cultivation of Lentinula edodes. We investigated the optimal major materials and its mixing ratio in bag cultivation of L. edodes, 'Sanjo701ho' and 'Nongjingo'. The Suitable substrates for L. edodes bag cultivation were oak sawdust and douglas fir sawdust and rice bran mixed ratio 40:40:20(v/v). At the result, the period mycelial incubation shortened up to 13~18 days compared to the control. And Yield of commercial fruiting bodies was 17~19% higher than that in control. We expect that the cultivation period of L. edodes will be shortened, and the yield increased in the medium replaced half of oak sawdust by douglas fir sawdust.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.51 no.6
• /
• pp.647-655
• /
• 2018

This study collected basic data on two types of canned roasted oyster Crassostrea gigas. Oysters Crassostrea gigas were immersed at $105^{\circ}C$ for 6 min and then washed and dehydrated before pre-drying. Roasted oysters were prepared by baking boiled oysters at $140^{\circ}C$ for 20 min. The canned roasted oyster added with tomato sauce was prepared as follows. An aluminum can was filled with 50 g of roasted oyster and 40 g of mixed seasoning sauce, degassed at $90^{\circ}C$ for 3 min and vacuum-sealed using a double seamer under a 20 cmHg vacuum. The canned roasted oyster added with tomato paste sauce was prepared similarly by adding the same amount of tomato paste sauce instead of tomato sauce. Microbial growth, appearance, proximate composition, pH, volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, amino-N, salinity, color value, texture, free and total amino acids, and minerals were measured in the two products. A sensory evaluation indicated that the canned roasted oyster added with tomato paste sauce had preferable characteristics over the canned roasted oyster sauce added with tomato sauce.