• Food Science and Preservation
• /
• v.18 no.6
• /
• pp.986-992
• /
• 2011

The alcohol fermentation of apple juice was optimized as a preliminary study for the production of natural apple cider vinegar. To gain an optimal fermentation yield, a central composite design was used to investigate the effects of the independent variables [initial Brix (12/14/16/18/20, $X_1$), fermentation time(48/54/60/66/72h, $X_2$), and fermentation temperature(24/26/28/30/$32^{\circ}C$, $X_3$)] on the dependent variables (alcohol content, reducing sugar, Brix, acidity). The alcohol content was 3.4-6.4%, the reducing sugar was 1.93-6.24%, and the Brix was $6.1-13.8^{\circ}$. The alcohol content was mainly affected by the fermentation temperature and increased along with the fermentation time and temperature. The amount of the reducing sugar was significantly affected by the initial Brix and fermentation temperature. The optimal conditions for the alcohol content were found to be 15.22 initial Brix, 64.97 h fermentation time, and $31.56^{\circ}C$ temperature.

• Journal of Venture Innovation
• /
• v.5 no.2
• /
• pp.85-99
• /
• 2022

Dryers becoming commercially available for experimental and industrial use are classified to general drying oven, hot-air dryer, vacuum dryer, freezing dryer, etc. and kinds of them are various from the function, size and volume, etc. But the moisture measurement is not applied although it is important factor for the quality control and the performance improvement of products, and then now is very passive because the weight is weighed arbitrarily after dry-end. Generally the method for measuring moisture is divided by a direct measurement method and a indirect measurement method, and the former such as the change of weight or volume on the front and rear of separation of moisture, etc. is mainly used. Relatively a indirect measurement is very limited to apply due to utilize measurement apparatuses using temperature conductivity and micro-wave etc. In this research, we easily designed the moisture measurement system using the open-source based Arduino, and monitored moisture fluctuations and weight profiles in the real-time without the effect of external environment. Concretely the temperature-humidity and load cell sensors were packaged into a drying oven and the various change values were measured, and their sensors capable to operate 60℃ and 80℃ were selected to suitable for the moisture sensitive materials and the food dry. And also the performance safety using the organic samples of banana, pear, sawdust could be secured because the changes of evaporation rate as the dry time and temperature, and the measurement values of load cell appeared stable response characteristics through repeated experiments. Hereafter we judge that the reliability can be improved increasingly through the expansion of temperature-humidity range and the comparative analysis with CFD(Computational Fluid Dynamics) program.

• Journal of Plant Biotechnology
• /
• v.35 no.4
• /
• pp.281-290
• /
• 2008

In plant, Receptor-like kinases (RLKs) are protein family, though its function is not yet understood, consisted of a predicted signal sequence, single transmembrane region, and cytoplasmic kinase domain. RLKs are involved in hormonal response pathways, cell differentiation, plant growth and development, self-incompatibility, and symbiont and pathogen recognition. In this study, expression levels of RLG1, RLG5, RLG6, RLG#6, RLG8, RLG10, RLG17, RLG18 and RLG20 were analyzed by Real-time PCR, when rice (Oryzae sativa) was treated abiotic stress. The expression levels of all RLGs were compared each other by analyzed value of threshold cycles ($C_T$). Consequently, RLGs were suppressed by NaCl as salinity stress, and expression of each RLK genes were showed difference treated salicylic acid and wound, respectively. However, All RLGs were induced under low temperature condition. Therefore, our results indicate protection-function of RLK genes to be an early response of rice against cold weather.

• Journal of Korean Society of Forest Science
• /
• v.105 no.1
• /
• pp.122-131
• /
• 2016

This study was conducted to analyze the effect of climatic variables on tree-ring growth of Larix leptolepis distributed in Korea by dendroclimatological method. For this, annual tree-ring growth data of Larix leptolepis collected by the $5^{th}$ National Forest Inventory were first organized to analyze yearly growth patterns of the species. To explain the relationship between tree-ring growth of Larix leptolepis and climatic variables, monthly temperature and precipitation data from 1950 to 2010 were compared with tree-ring growth data for each county. When tree-ring growth data were analyzed through cluster analysis based on similarity of climatic conditions, six clusters were identified. In addition, index chronology of Larix leptolepis for each cluster was produced through cross-dating and standardization procedures. The adequacy of index chronologies was tested using basic statistics such as mean sensitivity, auto correlation, signal to noise ratio, and expressed population signal of annual tree-ring growth. Response function analysis was finally conducted to reveal the relationship between tree-ring growth and climatic variables for each cluster. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics of Larix leptolepis and for predicting changes in tree growth patterns caused by climate change.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.17 no.2
• /
• pp.93-101
• /
• 2015

This study was conducted to analyze the relationship between tree-ring growth of Quercus acutissima and climatic variables by dendroclimatological method. Annual tree-ring growth data of Quercus acutissima collected by the $5^{th}$ National Forest Inventory (NFI5) were organized to analyze the spatial distribution of the species growth pattern. To explain the relationship between tree-ring growth of Quercus acutissima and climatic variables, monthly temperature and precipitation data from 1950 to 2010 were compared with tree-ring growth data for each county. When tree-ring growth data were analyzed through cluster analysis based on similarity of climatic conditions, four clusters were identified. In addition, index chronology of Quercus acutissima for each cluster was produced through cross-dating and standardization procedures. The adequacy of index chronologies was tested using basic statistics such as mean sensitivity, auto correlation, signal to noise ratio, and expressed population signal of annual tree-ring growth. Response function analysis was conducted to reveal the relationship between tree-ring growth and climatic variables for each cluster. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics of Quercus acutissima and for predicting changes in tree growth patterns caused by climate change.

• Journal of Korean Society of Forest Science
• /
• v.98 no.6
• /
• pp.733-739
• /
• 2009

This study was carried out to analyze the relationship between major climatic factors (monthly temperature, precipitation) and radial growth of Korean Pine (Pinus koraiensis) in Inje-gun(Mt. Seorak), Sanchung-gun and Namwon-si(Mt. Jiri). Radial growth measurements were crossdated and correlated with climate variables. The climatic factors used were monthly mean temperature and monthly precipitation from August of previous year to September of the current year. In Inje-gun, radial growth was negatively correlated with monthly mean temperature in April, May, June, and August of the current year and was positively correlated with precipitation in August, October of the previous year and in April, August of the current year. Sanchung-gun showed a negative correlation with monthly mean temperature in September of the previous year and August of the current year but positive correlation in January of the current year. In contrast, precipitation in September of the previous year and August of the current year showed a positive influence. The results suggest that high temperature together with low precipitation may thus cause water stress and thereby limit radial growth in this region. In Namwon-si, the climategrowth relationships show that radial growth was negatively correlated with monthly mean temperature in August, October of the previous year and June of the current year. But August of the previous year and May, August of the current year in precipitation was positively correlated with radial growth. In the study areas, precipitation plays an important role for the radial growth of Kroean Pine (Pinus koraiensis). The results suggest that precipitation is important in the radial growth because water deficit in trees would take place in response to high temperature in the study area. Also there was some differences with study areas in the effects of both climatic variables probably as a result of different stand structure and geographical conditions and micro-climate.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.3
• /
• pp.20-38
• /
• 2014

Vegetation phenology is the most important indicator of ecosystem response to climate change. Therefore it is necessary to continuously monitor forest phenology. This paper analyzes the phenological characteristics of forests in South Korea using the MODIS vegetation index with error from clouds or other sources removed using the HANTS algorithm. After using the HANTS algorithm to reduce the noise of the satellite-based vegetation index data, we were able to confirm that phenological transition dates varied strongly with altitudinal gradients. The dates of the start of the growing season, end of the growing season and the length of the growing season were estimated to vary by +0.71day/100m, -1.33day/100m and -2.04day/100m in needleleaf forests, +1.50day/100m, -1.54day/100m and -3.04day/100m in broadleaf forests, +1.39day/100m, -2.04day/100m and -3.43day/100m in mixed forests. We found a linear pattern of variation in response to altitudinal gradients that was related to air temperature. We also found that broadleaf forests are more sensitive to temperature changes compared to needleleaf forests.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2005.11a
• /
• pp.71-80
• /
• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.2
• /
• pp.367-377
• /
• 2018

Swimming crab(Ovalipes punctatus) is produced in Korea and utilized as semi-processed food at streamed cooked state. Recently, protein hydrolysates have been known as having function such as antioxidant, suppression of hypertension, immunodulatory, alleviation of pain, and antimicrobial activity. This research was investigated to find the functional antioxidant from crab hydrolysates. To fine optimal protease enzyme, alcalase, bromelain, flavourzyme, neutrase, papain, and protamex were selected to evaluate the DPPH radical scavenging activity and finally bromelain to show the best activity was selected. The molecular weight of bromelain hydrolysates were distributed with range from 500 to 3,200 Da and 7 different molecules or more. The amino acids related to antioxidant capacity was about 42.54%. The processes optimization study used was the response surface methodology. The ranges of processes were the reaction temperature of 40 to $60^{\circ}C$, pH 6 to 8, and enzyme concentration 1 to 3%(w/v). As a result, the optimization of process was determined at temperature of $55^{\circ}C$, pH of 6.5, and enzyme concentration of 3%(w/v). In these conditions, degree of hydrolysates were maximum 71.60%. Therefore, we expect that those products are useful as functional food ingredients.

• Journal of Plant Biotechnology
• /
• v.44 no.3
• /
• pp.220-228
• /
• 2017

Many crops including cereals, tuber crops, feeds, and turf grasses are often damaged by various environmental stresses such as drought, salt, cold, and high temperature, causing the reduction of their productivity. Plants are sessile and cannot escape from environmental stresses. Thus, plants evolve in the direction of overcoming the environmental stresses. Some plant genes such as ARF, ABI3, NAC, HSF, and WRKY are known to respond to environmental stresses as they transcriptionally regulate the stress response pathways. For example, the OsWRKY76 gene contributes to the enhanced resistance to low temperatures and pathogenic infections. The AtWRKY28 also plays a role in environmental stresses. Zoysiagrass (Zoysia japonica Steud.) is popularly grown for gardens and golf courses. However, the function of the WRKY gene, another environmental stress-related gene, is not known in zoysiagrass. In this study, the ZjWRKY3 and ZjWRKY7 genes with one shared WRKY domain have been isolated in zoysiagrass. The expression of these genes increased in response to low temperature, drought, and salt stresses. Furthermore, the infection of the brown patch-causing Rhozoctonia solani induced the expression of ZjWRKY3 and ZjWRKY7. The corresponding proteins bind to the W-box of the Zjchi promoter, possibly regulating their transcriptions. The researchers suggest that the ZjWRKY3 and ZjWRKY7 genes transcriptionally regulate abiotic and biotic stress related downstream genes.