• Applied Biological Chemistry
• /
• v.24 no.4
• /
• pp.207-212
• /
• 1981

Nutritional evaluation of nitrogen compounds of soybean and soybean sprout in various growth conditions various conditions was conducted by feeding Sprague-Dawley strain of albino rat and was correlated with chemical evaluation. food intake and PER also showed the same trend as weight gain. Average body fyeight gain showed significant positive correlation with essential amino acid index (EAAI) $(r=0.996^{**})$ and requirement index (RI) $(r=0.988^{**})$. According to EAAI and RI, quality of soybean sprout was in order of Soybean-heated, 4 days soybean sprout (S.S.) cotyledon, 4 days S.S heated, 8 days S.S heated and 4 days S.S axis heated. Process of soybean sprout (4 days growing at $25^{\circ}C$) caused quantitative loss of soybean protein by 4.5%, and quantitative loss of 11% (EAAI basis) in chemical evaluation while protein efficiency loss of 7% (PER basis) and overall nutritional loss of 18% (weight gain basis).

• Journal of the Korean earth science society
• /
• v.40 no.6
• /
• pp.599-605
• /
• 2019

Rice yield (kg 10a^-1) in South Korea was estimated by meteorological variables that are influential factors in crop growth. This study investigated the possibility of anticipating the rice yield variability using a simple but an efficient statistical method, a multiple linear regression analysis, on the basis of the annual variation of meteorological variables. Due to heterogeneous environmental conditions by region, the yearly rice yield was assessed and validated for each province in South Korea. The monthly mean meteorological data for the period 1986-2018 (33 years) from 61 weather stations provided by Korean Meteorological Administration was used as the independent variable in the regression analysis. An 11-fold (leave-three-out) cross-validation was performed to check the accuracy of this method estimating rice yield at each province. This result demonstrated that temporal variation of rice yield by province in South Korea can be properly estimated using such concise procedure in terms of correlation coefficient (0.7, not significant). Furthermore, the estimated rice yield well captured spatial features of observation with mean bias of 0.7 kg 10a^-1 (0.15%). This method may offer useful information on rice yield by province in advance as long as accurate agro-meteorological forecasts are timely obtained from climate models.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.1
• /
• pp.52-57
• /
• 2005

Previous studies showed that shell meal fertilizer from the oyster farming industry could be a potential inorganic soil amendment to increase Chinese cabbage productivity and to restore the soil nutrient balance in upland soil (Lee et al., 2004). Herein, shell meal fertilizer was applied at rates of 0, 4, 8, 12, and $16Mg\;ha^{-1}$ to upland soil (Pyeontaeg series, Fine silty, Typic Endoaquepts) for Chinese cabbage cultivation. We found available phosphate increased significantly with shell meal fertilizer application, due to high content of phosphate ($1.5g\;P_2O_5\;kg^{-1}$) in the applied shell meal fertilizer. In addition, high pH of shell meal fertilizer contributed to increase available phosphate content by neutralization of acidic soil. Total and residual P contents increased significantly with increasing shell meal fertilizer application, but we could not find any tendency in organic and inorganic P fraction. Of extractable P fraction, water-soluble phosphorus (W-P) and calcium-bound P (Ca-P) contents increased significantly with increasing application level. By contrast, aluminum and iron-bound P (Al-P and Fe-P) decreased slightly with shell meal application. The present experiment indicated that shell meal fertilizer had a positive benefit on increasing available phosphate content in arable soil. And so the increased available phosphate by shell meal fertilizer may decrease phosphate application level and then reduce phosphorus loss in arable soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.1
• /
• pp.45-51
• /
• 2005

As a silicate source to rice, a coal ash (50%) was mixed with a phosphogypsum (hereafter, gypsum, 50%). Field experiments were carried out to evaluate rice (Oryza sativa) productivity in silt loam (SiL) to which 0, 20, 40 and $60Mg\;ha^{-1}$ of the mixture were added. The mixture increased rice yield and showed the highest yields following the addition of $30Mg\;ha^{-1}$. The mixture did not result in an excessive uptake of heavy metals by the rice grain. The mixture improved available silicate and phosphate and exchangeable calcium contents in soil. The available boron content in soil increased with the mixture application levels up to $1.42mg\;kg^{-1}$ following the application of $60Mg\;ha^{-1}$, but boron toxicity in rice was not found. It is concluded that the coal ash and gypsum mixture could be a good alternative to inorganic soil amendments to restore the soil nutrient balance in paddy soil.

• Journal of Sericultural and Entomological Science
• /
• v.48 no.2
• /
• pp.41-45
• /
• 2006

Mulberry leaves contain many natural components and are considerable resource for natural antiokidants. The antioxidant effect of 'Cheongilppong' collected from Chuncheon, Suwon and Wanju regions were investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The measurement parts were mulberry leaves collected from different areas and some kinds of mulberry branches. We obtained that even if samples were same variety, antioxidant capacity of those showed different results according to collected regions. Also, antioxidant effect of mulberry leaves were higher than that of branches. The order of antioxidant effect in Spring was Chuncheon > Suwon > Wanju. The antioxidant effect of mulberry leaves collected from Chuncheon, Suwon and Wanju regions of just before the coloration stage with anthocyanin in fruits were 3627.5 nmol, 2620.0 nmol 1360.7 nmol (ascorbic acid equivalents), respectively. In Autumn, the antioxidant effect and hardness quality of mulberry leaves were increased gradually until just before fallen leaves stage. Therefore, we concluded that being the most suitable period for collecting mulberry leaves as a antiokidant resource is from the latter part of May to the first ten days of June.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.6
• /
• pp.526-530
• /
• 1994

This study was conducted to investigate photosynthetic response to four sequential air influx rate with rice(Oryza sativa L.)plants moved from a natural condition to constant condition with automatic regulation selected environmental variables on 13th~15th days after anthesis. In time course of photosynthetic response to increasing air influx rate(200-280-360-440 ml / min.), stomatal conductance decreased rapidly at the beginning after treatment and then oscillated with a free-running period of a approximately 1 hour to 1 hour 30 minutes until reached up to steady-state condition. Similar change was also observed $CO_2$ assimilation rate. Stomatal conductance decreased throughout the air influx rate sequence, but the rate of decrease was similar to the decrease in $CO_2$ assimilation rate observed under continuous air influx rate conditions. In starch granules during grain filling period under air influx rate(440 ml / min.) , compound starch granules were loosing and a number of hollows were observed in surface of single starch granules. Evidences from several approaches indicate that synchronization of stomatal conductance and$CO_2$ assimilation rate was closely inter-related tinder increase of air influx rate and increase of air influx rate influenced the$CO_2$ uptake in photosynthetic processes and compound starch granule, as 'end products' of photosynthesis.

• Microbiology and Biotechnology Letters
• /
• v.31 no.3
• /
• pp.250-256
• /
• 2003

Lactic acid bacteria with amylolytic and acid producing activities can ferment starch directly to lactic acid thereby producing a monomer for the production of biodegradable poly lactic acid (PLA). In this study, the strain producing L-lactic acid from soluble starch was isolated from Nuruk. The isolated strain was identified as Enterococcus sp. through its morphological, cultural, biochemical characteristics as well as the 16S rDNA sequence analysis, and named Enterococcus sp. JA-27. Enterococcus sp. JA-27 produced exclusively L-lactic acid from soluble starch as a carbon source. The optimal conditions for the maximum production of L-lactic acid from Enterococcus sp. JA-27 were 30 C, pH 8, 1.5 % soluble starch as a substrate and 3.5 % tryptone as a nitrogen source, 0.1 % $K_2$$HPO_4$, 0.04 % $MgSO_4$. $7H_2$O, 0.014 % $MnSO_4$$.$4$H_2O$, 0.004% $FeSO_4$$.$$7H_2$O. Batch and fed batch culture were carried out and the former was more effective. L-Lactic acid production in the optimum medium was significantly increased in a 7 L jar fermenter, where the maximum L-lactic acid concentration was 3 g/L. For the purification of lactic acid in fermented broth, two stage ionexchange column chromatographies were employed and finally identified by HPLC.

• Microbiology and Biotechnology Letters
• /
• v.44 no.3
• /
• pp.293-302
• /
• 2016

To determine the dominant bacterial species during the Saeu-jeotgal ripening process, the cultivable bacterial population was examined over a 135-day period using six different growth media. The greatest numbers of bacteria were identified when marine agar was used for culture, with maximum cell density identified at day 65 (2.51 × 10⁷ colony forming units/g). Over the course of 135 days, the bacterial diversity was analyzed eight times. A total of 467 isolates, comprising 87 species from 42 genera, as well as 16 isolates belonging to previously unknown species, were identified. The number of species detected decreased from 39 at day 1 to 13 at day 135. The order of dominance at the genus level was as follows: Staphylococcus, Salimicrobium, Kocuria, and Psychrobacter. Staphylococcus and Salimicrobium accounted for 2% of the diversity at day 1, and then increased to 39% and 36%, respectively, at day 135. The dominant species Staphylococcus equorum, Salimicrobium salexigens, and Kocuria palustris accounted for 23.6%, 16.1%, and 10.9% of all isolates, respectively. Importantly, both St. equorum and Sm. salexigens remained viable at a NaCl concentration of 21% (w/v), which indicates their strong involvement in the ripening of Saeu-jeotgal.

• Applied Biological Chemistry
• /
• v.46 no.2
• /
• pp.134-139
• /
• 2003

To establish the fertilization condition to increase the productivity of Chasanthemum boreale M. with high quality, the effects of three nutrients (N, P, K) on the yields and the effective components were investigated in the pot scale. NPK was applied by chemical fertilizers with $(N-P_2O_5,-K_2O=250-160-160\;kg/ha)$ as a main treatment, and NP $(N-P_2O_5,-K_2O=250-160-160\;kg/ha)$, NK $(N-K_2O =250-160\;kg/ha)$, and PK $(P_2O_5K_2O=160-160\;kg/ha)$ treatments were settled as comparison. Dry yields of C. boreale M. was increased significantly to 4 fold higher by nitrogen. Nitrogen increased apparently plant growth and inorganic nutrient uptake. In the flower, which is most useful and edible part as a herbal medicine, main amino acids were glutamic acid and aspartic acids, and the total content was increased significantly by three elements of application. In addition, the content of cumambrin A, which is known to have the effect of blood-pressure reduction, was increased source to 6.2 times by nitrogen higher than that in PK treatment. Potassium was more effective in biosynthesis of cumambrin A than phosphorus, but the biological pathway was not clear, still.

• Journal of Applied Biological Chemistry
• /
• v.58 no.4
• /
• pp.311-316
• /
• 2015

Yogurt was prepared with different substitution ratio [10, 30, and 50% (w/w)] of skim milk with enzymatically hydrolyzed purple sweet potato powder (EHPSPP) and fermented at $40^{\circ}C$ for 15 h. Fermentation characteristics and antioxidant activities of the yogurt were evaluated in terms of acid production (pH and titratable acidity) and lactic acid bacterial counts and DPPH radical scavenging activity, respectively. After 15 h fermentation, titratable acidity of EHPSPP yogurt was 0.80-0.89% and was lower than that (0.93%) of yogurt made without EHPSPP. The acid production and the number of viable lactic acid bacterial cell decreased with increasing the substitution ratio. The sensory score of EHPSPP yogurt prepared with 30% substitution ratio showed the highest values in taste and overall acceptability among the tested yogurt preparations. DPPH radical scavenging activity increased with increasing the substitution ratio in yogurt fermented for 12 h. The total phenolic content of 30% EHPSPP yogurt was 40% higher than that of skim milk yogurt. These results suggest that EHPSPP can be used as substituent of skim milk and the optimum substitution ratio is around 30%.