• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.363-370
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• 2018

The succulent plants of Echeveria genus are in increasing demand worldwide, but it is difficult to supply good quality young plants throughout the year because propagation efficiencies are depend on cultivar and environmental factors. This study was carried out to investigate the propagation efficiencies of leaf cutting in Echeveria cultivars at different LED light qualities in a closed-type plant factory system. Leaf cuttings cut from stock plants of six difficult-to-propagated cultivars 'Afterglow (AG)', 'Berkeley Light (BL)', 'Mason (MS)', 'Subsessilis Light (SL)', 'Cream Tea (CT)', and 'Ben Badis (BB)' were put into cutting media in the plant factory system maintained at a temperature of $24{\pm}2^{\circ}C$ and relative humidity of $60{\pm}10%$, and watered with over-head irrigation twice a week. Cuttings were irradiated with sole or mixed red (R, 660 nm), blue (B, 450 nm), green (G, 530 nm), and far-red (FR, 730 nm) LEDs as follows: R10, R8+B2, R5+B5, R7+B2+FR1, and R7+B2+G1. PPFD just above the cuttings was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and photoperiod was 16/8 (light/dark) hours. As a result, propagation efficiencies were dependent on cultivar. Rooting and shooting were relatively easy in 'SL' but shoot formation in 'AG' was very difficult. Light qualities from LEDs also affected plant regeneration. Light conditions with a higher ratio of B, R5+B5, R7+B2+FR1, and R7+B2+G1, promoted shoot formation and growth but inhibited rooting and root growth. R10 and R8+B2 with a higher ratio of R promoted rooting and root growth and inhibited shoot formation and growth of cuttings. In addition, the treatment with FR increased leaf size and biomass of the all plants. Therefore, further studies are needed to investigate the optimum compositions of LED light quality for the improvement of leaf cutting efficiency in difficultto-propagated Echeveria cultivars.

• Journal of Mushroom
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• v.11 no.3
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• pp.154-158
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• 2013

To develop a new variety of oyster mushroom(Pleurotus ostreatus), parental strains was selected by the method of Mon-Mon crossing between monokaryotic strains derived from ASI 2596(Suhan No.3) and ASI 2782(Black pileus mutant). The SB-73(ASI 2596-11 x 2782-8) was shown the best cultural characteristics, selected to be a new variety and named as 'Dagul'. The 'Dagul' was formed incompatibility line distinctly in the confrontation growth of parental strains Suhan No.3 and ASI 2782. The optimum temperature for mycelial growth, fruiting body development and pH arrange were $25{\sim}30^{\circ}C$, $14{\sim}17^{\circ}C$ and pH5~8, respectively. Fruiting body production per bottle was about $68.0{\pm}24.1$ g which is almost 115% quantity compared to that of other variety Suhan No.3. And also the stipe is long and individual generation is multiple. Analysis of the genetic characteristics of the new variety 'Dagul' showed different DNA bands as that of the control strains, Suhan No.3 and ASI 2782, when RAPD(Random Amplified Polymorphic DNA) primers URP7 and Rcb1 were used. This new variety 'Dagul' of oyster mushroom is characterized by multiple of individual generation and the stipe is long. We therefore expect that this new strain will increase of the income by cultivation of field.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.397-403
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• 2012

This study compared the Aphelinus varipes and Aphelinus asychis in terms of how they parasitized the cotton aphid, Aphis gossypii and green peach aphid, Myzus persicae. Host-feeding, parasitism, emergence, the proportion of females and development time were all studied at 15, 20, 25 and $30^{\circ}C$ in controlled climate cabinets. When A. gossypii were provided for the two aphid parasitoids, the number of aphids killed by host-feeding for A. varipes (5.4 and 9.7 aphids) at $15^{\circ}C$ and $25^{\circ}C$ was higher than those for A. asychis (2.0 and 2.9 aphids). At $15^{\circ}C$ and $30^{\circ}C$, the parasitized A. gossypii were higher in A. varipes (11.1 and 21 aphids) than in A. asychis (7 and 12.3 aphids). The emergence rate was also significantly different between A. varipes (83.3%) and A. asychis (69.4%). The proportion of females was higher for A. asychis (75.2 and 73.9%) than for A. varipes (19.5 and 48.6%) at $15^{\circ}C$ and $30^{\circ}C$, respectively. No significant differences were found in development time between the two parasitoids. When M. persicae were provided for the two parasitoid species, the host-feeding number and the emergence rate of two parasitoids were not different at all four temperatures. The M. persicae were more highly parasitized by A. varipes (12.1 and 17.1 aphids) than by A. asychis (6.1, 10 aphids) at 20 and $25^{\circ}C$. The proportion of females for A. varipes (65.3 and 90.0%) was higher than that for A. asychis (34.4 and 78.8%) at $15^{\circ}C$ and $25^{\circ}C$. The development time from oviposition to the adult emergence of A. varipes (19.9 d) was significantly longer than that of A. asychis (16.5 d) at $20^{\circ}C$. Development times decreased with increasing temperature for both in two parasitoid species.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.166-185
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• 1983

Aspergillus niger IFO 8541 (NRRL 3112) was investigated through a series of UV rays and N-Methyl-N'-Nitro-N-Nitrosoguanidine (NTG) treatments to induce mutants that produce highly active raw starch saccharifying enzyme, and two mutants with strong enzymatic productivity were obtained. The mutants obtained were investigated for their fungal characters, condition of enzyme production, and other activities. Furthermore, the raw starch saccharifying enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were summarized as follows; 1. The color of conidial head of UV-46 mutant obtained from UV rays treatment was changed to tan type and the gelatinated starch saccharifying enzyme productivity and the raw starch saccharifying enzyme productivity increased up to twice and 1.8 times compared to the productivities of original Aspergillus niger IFO 8541 cultured on the wheat bran, respectively. 2. The conidial head color of NG-41 mutant obtained from NTG treatment became lighter than that of parent strain. The gelatinated starch saccharifying enzyme productivity and raw starch saccharifying enzyme productivity increased about 1.8 times, and twice over the Aspergillus niger IFO 8541 parent strain cultured on wheat bran, respectively. The productivity of ${\alpha}$-amylase increased about 3 times more than the parent strain. 3. Two peaks of glucoanlylase and a peak of ${\alpha}$-amylase were obtained when enzyme solution of mutants and parent strain were passed through DEAE-Sephadex A-50 column chromatography. Glucoamylase I showed only gelatinated starch saccharifying enzyme activity. However, glucoamylase II (raw starch saccharifying enzyme) showed both raw starch saccharifying enzyme activity and gelatinated starch saccharifying enzyme activity. 4. Mutant, UV-46 was strengthened in glucoamylase II productivity and mutant NG-41 was strengthened in ${\alpha}$-amylase productivity. 5. Glucoamylase II of mutants and parent strain were appeared to have the same enzymatic properties. 6. Glucoamylase II of mutants and parent strain were recognized as simple enzyme through electrophoresis. 7. The glucoamylase II crystallized showed rhombic board type. 8. The molecular weight, isoelectric point, optimum pH, and optimum temperature of the glucoamylase II crystallized were estimated as 76,000, 3.4, 3.5 and $60^{\circ}C$, respectively.

• Food Science and Preservation
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• v.22 no.1
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• pp.84-90
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• 2015

The physicochemical properties and protease activities of spray-dried pineapple juice powders were investigated. The pH, soluble solids, and protease activity of the pineapple juice were pH 5.43, $12.8^{\circ}Brix$, and 4.82 unit/mL, respectively. The optimum pH and temperature of the protease activity from pineapple juice were pH 7.0 and $50^{\circ}C$, respectively. The microencapsulation of pineapple juice was achieved using maltodextrin and alginic acid through spray-drying. The L value and moisture content of the spray-dried powder were higher than those of the freeze-dried powder. The particle size of the freeze-dried powder ($501.57{\mu}m$) was higher than that of the spray-dried powder ($42.58-53.32{\mu}m$). The water absorption and water solubility of the powders were 0.41-0.87, and 90.45-99.76%, respectively. When compared, the protease activities were found to be in the following order : FD (1,297.47 unit/g) > SD-MA-1 (692.08 unit/g) > SD-MA-2 (664.66 unit/g) > SD-MA-3 (642.65 unit/g) > SD-M (633.51 unit/g). In the in vitro dissolution study measurements were conducted for 4 hr in pH 1.2 simulated gastric fluid and pH 6.8 simulated intestinal fluid, using a dissolution tester at $37^{\circ}C$ in 50 rpm. The protease survival of the 3.74-15.69% microencapsulated pineapple juice powders improved with an increase in the treatment concentration of alginic acid.

• Food Science and Preservation
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• v.16 no.5
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• pp.661-668
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• 2009

A total of 107 pearled barley products produced in Korea, 58 non-waxy and 49 waxy, were analyzed for protein and $\beta$-glucan content, whiteness, cooking characteristics (water absorption and expansibility), and pasting properties, with respect to the region of production. We compared non-waxy and waxy pearled barley products and sought correlations between levels of chemical components and cooking characteristics. Waxy pearled barley products had higher concentrations of protein (7.17-12.57%, w/w) and $\beta$-glucan (2.81-7.38%, w/w), a higher whiteness grade (27.1-49.6), and a greater water absorption (218-593%) and expansibility (366-593%) than did non-waxy barley products. The pasting temperature of non-waxy pearled barley ($73.9^{\circ}C$) was higher than that of waxy pearled barley ($66.9^{\circ}C$). Peak viscosity, hot paste viscosity, and final viscosity of non-waxy pearled barley products were higher than those of waxy products. The results showed that waxy pearled barley products had better cooking characteristics than did non-waxy products. A significant positive correlation was observed between protein and $\beta$-glucan content in both non-waxy and waxy pearled barley products ($r=0.632^{***}$ and $r=0.453^{**}$, respectively). Whiteness showed a negative correlation with protein content of both non-waxy and waxy pearled barley products ($r=-0.433^{***}$, $r=-0.343^{**}$). However, neither water absorption nor expansibility showed any significant correlation with protein or $\beta$-glucan content. The waxy ratio of 49 waxy pearled barley products ranged from 84-100%.

• Korean Journal of Food Science and Technology
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• v.7 no.4
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• pp.229-237
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• 1975

An attempt was made to utilize the enzyme produced by Asp. oryzae as meat tenderizer. The production, purification, and various properties of proteinase produced by Asp. oryzae were investigated. Results obtained are as follow; 1. A strain which had the highest proteolytic activity was selected among 9 Aspergillus species. 2. Culture medium consisted of wheat bran 10g, 2% glucose, 0.03% urea and 0.1% $MgSO_4$ (pH 6.5). Mold was incubated at $30^{\circ}C$ for 3 days. 3. Enzyme extract from culture medium were fractionated with ammonium sulfate and purified by Sephadex G-75 column chromatography. 4. When pH of reaction mixture was controlled, maximal activity of proteinase by Asp. oryzae was obtained at pH 3, pH 6.6, $8.4{\sim}8.5$ and pH 10.0 to 10.5. Those results were interpreted to show that enzyme consists of acid proteinase, neutral proteinase and alkaline proteinase. Enzyme was stable at pH 6 to 10. 5. Opt. temperature for proteinase activity was $50^{\circ}C$, but enzyme was stable up to $40^{\circ}C$. 6. The proteinase was inhibited by $Ag^+$. It was also inhibited by EDTA. 7. When myofibrillar proteins were treated by proteinase from Asp. oryzae, ATPase activities of myofibrillar proteins changed remarkably. Accordingly, it was concluded that proteinase produced by Asp. oryzae were able to be used as meat tenderizer.

• Journal of Life Science
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• v.21 no.1
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• pp.119-126
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• 2011

There is a growing recognition of the significance of $H_2S$ as a biological signaling molecule involved in vascular and nervous system functions. In mammals, two enzymes in the transsulfuration pathway, cystathionine ${\beta}$-synthase (CBS) and cystathionine ${\gamma}$-lyase (CGL), are believed to be chiefly responsible for $H_2S$ biogenesis. Genetic inborn error of CGL leads to human genetic disease, cystathioninuria, by accumulating cystathionine in the body. This disease is secondarily associated with a wide range of diseases including diabetes insipidus and Down's syndrome. Although the human CGL (hCGL) overexpression is essential for the investigation of its function, structure, reaction specificity, substrate specificity, and protein-protein interactions, there is no clear report concerning optimum overexpression conditions. In this study, we report a detailed analysis of the overexpression conditions of the hCGL using a bacterial system. Maximum overexpression was obtained in conditions of low culture temperature after inducer addition, performing low aeration during overexpression, and using a low concentration inducer (0.1 mM, IPTG) for induction. Expressed hCGL was purified by His-tag affinity column chromatography and confirmed by Western blot using hCGL antibody and enzyme activity analysis. We also report that the His tag with TEV site attached protein exhibits 76% activity for ${\alpha}-{\gamma}$ elimination reaction with L-cystathionine and 88% for ${\alpha}-{\beta}$ elimination reaction with L-cysteine compared to those of wild type hCGL, respectively. His tag with TEV site attached protein also exhibits a 420 nm absorption maximum, which is attributed to the binding cofactor, pyridoxal 5'-phosphate (PLP).

• Journal of Life Science
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• v.22 no.10
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• pp.1295-1306
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• 2012

A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater and identified as Bacillus atrophaeus. This species was designated as B. atrophaeus LBH-18 based on its evolutionary distance and the phylogenetic tree resulting from 16S rDNA sequencing and the neighbor-joining method. The optimal conditions for rice bran (68.1 g/l), peptone (9.1 g/l), and initial pH (7.0) of the medium for cell growth was determined by Design Expert Software based on the response surface method; conditions for production of CMCase were 55.2 g/l, 6.6 g/l, and 7.1, respectively. The optimal temperature for cell growth and the production of CMCase by B. atrophaeus LBH-18 was $30^{\circ}C$. The optimal conditions of agitation speed and aeration rate for cell growth in a 7-l bioreactor were 324 rpm and 0.9 vvm, respectively, whereas those for production of CMCase were 343 rpm and 0.6 vvm, respectively. The optimal inner pressure for cell growth and production of CMCase in a 100-l bioreactor was 0.06 MPa. Maximal production of CMCase under optimal conditions in a 100-l bioreactor was 127.5 U/ml, which was 1.32 times higher than that without an inner pressure. In this study, rice bran was developed as a carbon source for industrial scale production of CMCase by B. atrophaeus LBH-18. Reduced time for the production of CMCase from 7 to 10 days to 3 days by using a bacterial strain with submerged fermentation also resulted in increased productivity of CMCase and a decrease in its production cost.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.95-101
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• 1997

This study was conducted to investigate how a labor saving for conventional hand sowing and respond to major agronomic traits under different planting density in 1993 and 1994. Each trial was a randomized block split plot with row spacing as the main plots and hill spacing as subplots. Sowing rate appeared lower in 20 or 25cm hill spacing using machine seeder than in hand sowing. Sowing time required reduced more 121 hours per hectare in 60cm row, 20cm hill spacings using machine seeder than in hand sowing. Increasing row and hill spacings reduced number of seedling stand per unit $area(m^2)$. Both number of pods per plant and grain weight per plant and showed highly increase in wide planting. Best yield obtained in 60cm row, 20cm hill spacing using machine seeder. Accumulative mean air temperature was positively correlated with stem height, number of pods per plant and yield, otherwise accumulative rainfall was negatively correlated with ones. A highly significant negative correlation was showed between number of seedling stand per unit $area(m^2)$ and number of branches, number of pods per plant, grain weight per plant and yield. Yield was positively correlated with number of branches, number of pods per plant and grain weight per plant.