• Journal of Bio-Environment Control
• /
• v.7 no.3
• /
• pp.259-267
• /
• 1998

This study was carried out to investigate the effect of mulching materials on the fruit quality of Miyagawa Early Satsuma Mandarin in the plastic house. The mulching time was 10 days after water irrigation breakage. The mulching materials used, in order of decreasing light reflectivity, were; micro-perforated vinyl sheets, non-woven fabric film, porous black P.E. film and non-mulching(control). Peel coloration by a values in the treatment of the micro-perforated vinyl sheets showed a 6.93 increase over the control group. The a/b values were similar to this trend, but there were no significant difference among the mulching treatment groups. The glucose level of fruit juice was much higher in the mulching treatment groups as compared with that of the control group, but there was no significant difference among the mulching treatments. Fructose content in the treatment of the micro-perforated vinyl sheets a 0.31mg%.m $L^{-1}$ increase over the control group. This group also showed a 1.36%.m $L^{-1}$ increase in sucrose and a similar increase trend in total sugar. The Brix value was 0.9 $^{\circ}$Brix higher in the micro-perforated vinyl sheet group(12.4 $^{\circ}$Brix) than in the control group(11.5 $^{\circ}$Brix) which result in a significant increase with micro-perforated vinyl sheet usage. However, the acidity level did not differ significantly among mulching treatments.

• Journal of Bio-Environment Control
• /
• v.20 no.3
• /
• pp.204-210
• /
• 2011

This experiment was conducted to investigate the effect of water states (water, osmotic potential and turgor pressure) of fruit vesicle and leaf on soluble solids and organic acid contents of fruits of 'Shiranuhi' mandarin hybrid, M16 A line during the fruit maturing season in plastic house cultivation. The 'Shirauhi' grafted on 'Swingle citrumelo', strong strength of rootstock, produced fruit with lower soluble solids and organic acid content than 'Trifoliate' orange rootstock. The fruits vesicle water potential and turgor pressure measured before dawn in 'Swingle citrumelo' were higher tendency than the 'Trifoliate' orange, but osmotic potential values were lower than the 'Trifoliate' orange. The changes of leaf water potential were very similar to the fruit. The results suggest that in the 'Shirauhi' fruits grafted on two rootstocks changes of soluble solids and organic acid content of the fruit were influenced by the leaf water potential and the osmotic potential of the fruit vesicles, which might be caused by the difference of root distribution between two rootstocks.

• Microbiology and Biotechnology Letters
• /
• v.46 no.1
• /
• pp.77-84
• /
• 2018

An increase in $CO_2$ will affect plant pathogenic microorganisms, the resistance of host plants, and host-pathogen interactions. This study used Capsicum annuum and Xanthomonas euvesicatoria, a pathogenic bacterium of pepper, to investigate the interactions between hosts and pathogens in conditions of increased $CO_2$ concentrations. Our analysis of disease resistance genes under 800 ppm $CO_2$ using quantitative RT-PCR showed that the expression of CaLRR1, CaPIK1, and PR10 decreased, but that of negative regulator WRKY1 increased. Additionally, the disease progress and severity was higher at 800 ppm than 400 ppm $CO_2$. These results will aid in understanding the interaction between red pepper and X. euvesicatoria under increased $CO_2$ concentrations in the future.

• Journal of Nutrition and Health
• /
• v.53 no.1
• /
• pp.1-12
• /
• 2020

Purpose: Diabetic nephropathy is one of the most important diabetic complications prompted by chronic hyperglycemia, characterized by glomerulosclerosis, tubular fibrosis, and it eventually causes kidney failure. Nobiletin is a polymethoxyflavone present in tangerine and other citrus peels, and has anti-cancer and anti-inflammatory effects. This study investigated the effects of nobiletin on glomerular fibrosis through inhibition of the transforming growth factor (TGF)-β1-Src-caveolin-1 pathway. Methods: Human renal mesangial cells (HRMC) were incubated in media containing 33 mM glucose with or without 1-20 uM nobiletin for 3 day. The cellular expression levels of fibrogenic collagen IV, fibronectin, connective tissue growth factor (CTGF), TGF-β1, Src and caveolin-1 were all examined. In addition, TGF-β1, Src and caveolin-1 proteins were screened to reveal the relationship among TGF-β1-Src-caveolin-1 signaling in glomerular fibrosis. Results: High glucose promoted the production of collagen IV, fibronectin and CTGF in HRMC, which was inhibited in a dose dependent manner by 1-20 uM nobiletin. The Western blot data showed that high glucose elevated the expression of TGF-β1, Src, caveolin-1 and Rho GTPase. When nobiletin was treated to the HRMC exposed to high glucose, the expression of TGF-β1-Src-caveolin-1 was dampened. Finally, TGF-β1-Src-caveolin-1 signaling pathway was activated in high glucose-exposed HRMC, and such activation was encumbered by nobiletin. Conclusion: These result demonstrated that nobiletin blunted high glucose-induced extracellular matrix accumulation via inhibition of the TGF-β1-Src-caveolin-1 related intracellular signaling pathway. Nobiletin may be a potent renoprotective agent to counteract diabetes-associated glomerular fibrosis that leads to kidney failure.

• Applied Biological Chemistry
• /
• v.13 no.3
• /
• pp.237-242
• /
• 1970

Fifty strains of mold which isolated from the various sources were screened for the production of Naringinase which hydrolyse naringin, the 7-rhamnoe-glucoside of 4'.5.7. - trihydroxyflavanonin, the main bitter principle of citrus fruits and grape fruits. Of the 4 strains yielded naringinase with significant activity, S-1 strain was selected on the criterion of industrial application, and some properties of crude naringinase of this S-1 was investigated. The results obtained were as follows. 1. Naringenase obtained from S-1 strain has optimum pH range from 3.0 to 5.0 for its activity. 2. Production of naringinase was increased on the addition of naringin to the medium. 3. Hydrolysis of naringin with approporiate concentration of naringinase was carried out linerly up to 80% on the 0.1% substrate solution. 4. The optimum temperature for its activity was $50^{\circ}C$, and this enzyme was inactivated 80% of its total activity at $70^{\circ}C$ for 10 minutes, 40% at $60^{\circ}C$ for 30 minutes. But signifiant decrease of activity were not occurred by heat treatment at $50^{\circ}C$ for 2 hours. 5. Crude enzyme of the naringinase obtained from S-1 strain was competitively inhibited by addition of glucose on the substrate, and inhibitor constant of the glucose on the this enzyme was 1.5 Mol, and inhibition rate were linearly increased according to the increase of sucrose concentration and 56% of its total activity was inhibited at 1 Mol sucrose solution.

• Journal of Bio-Environment Control
• /
• v.25 no.1
• /
• pp.57-62
• /
• 2016

This study was conducted to find out the influence of red LED (Light Emitting Diode) lighting on the photosynthesis, vegetative growth and fruit quality of 'Fuji'/M.26 adult apple tree during night after sunset. The photosynthetic rate, stomatal conductance and transpiration rate at daytime of red LED treatments was not different to those of the control. However, the stomatal conductance and transpiration rate at the nighttime of red LED treatments were lower than those of the control, and the red LED lighting during night after sunset was not induce to photosynthesize at nighttime. In the leaf characteristics, the red LED lighting seemed to increase leaf area and C/N ratio, but decrease SPAD value. The bourse shoot length of the red LED treatments was shorter than that of the control. In the fruit quality, the red LED lighting seemed to increase ethylene production, respiration rate, soluble solid content and fruit red color, and especially the fruit red color tend to increase as the red LED lighting time was longer. In conclusion, the red LED lighting during night after sunset of 'Fuji'/M.26 apple tree promoted the fruit maturation.

• Korean Journal of Microbiology
• /
• v.50 no.3
• /
• pp.227-232
• /
• 2014

In this study, Gluconacetobacter sp. gel_SEA623-2 isolated from citrus that produces bacterial cellulose was used to examine the effect of initial concentration of acetic acid and mixed culture inoculated with Lactobacillus plantarum KCCM 80077 on productivity of bacterial cellulose. In mixed culture added with 0.5% acetic acid, the viable cell count increased from $2.4{\times}10^6CFU/ml$ to $1.1{\times}10^7CFU/ml$ after 14 days of culture, and total acidity was about 0.3% higher than single culture added with 0.5% acetic acid, which implies that additional lactic acid was produced by L. plantarum KCCM 80077. In single culture, although bacterial cellulose productivity was higher when the initial concentrations of acetic acid were 0.0% and 0.5%, than when it was 1.0%, there was no significant difference. However, in mixed culture, adding 0.5% acetic acid resulted in dry weight of $37.83{\pm}6.81g/L$ and thickness of $10.33{\pm}0.58mm$, showing a significant difference from that of single culture added with 1% acetic acid, $28.40{\pm}1.23g/L$ and $7.50{\pm}0.50mm$ (P<0.05).

• Applied Biological Chemistry
• /
• v.42 no.2
• /
• pp.99-104
• /
• 1999

Soil actinomycetes of 703 strains were isolated from 25 sampling points in Cheju Island using 4 different media. Arginine glycerol salts agar containing soil extract was found to be the best medium for the isolation of soil actinomycetes. Soil samples from pasture land showed higher population and diversity of the actinomycetes than those from citrus field, forest, island, hill or valley. When the antibacterial activity of the 526 isolates was tested against three bacterial strains, Escherichia coli, Staphylococcus aureus and Pseudomonas solanacearum the frequency of the isolates with antibacterial activity varied much depending upon the media used for isolation and cultivation. BL106Ba, one of the 10 isolates that showed antibacterial activity against all the above 3 test strains, was chosen based upon the pH and heat stability of its antibacterial metabolites, and was identified as Streptomyces sp. based upon its cultural, morphological and physiological characteristics. The partially purified white crystalline substance obtained from the culture supematant of BL1063a through cation exchange chromatography(AG MP-50) and three times consecutive gel filtration(Sephadex G-10) showed high antimicrobial activity against gram positive and negative bacteria, but low activity against yeasts. The partially purified substance was found to contain at least four different compounds with antibacterial activity by both thin layer chromatography and high performance liquid chromatography.

• Applied Biological Chemistry
• /
• v.24 no.1
• /
• pp.59-66
• /
• 1981

Trichoxanthes Kirilowii with high starch-content was investigated to utilize as a food source. The weight and starch content of Trichoxanthes Kirilowii roots increased rapid1y in proporion to the growth period. The seasonal variations of the starch content were $36.5{\sim}48.0%$ (dry basis) from June to December. The chemical properties of natural growth soils of Trichoxanthes Kirilowii contained more organic matter and total nitrogen content than citrus orchard soils, but less mineral; P,K,Ca and Mg. To prepare starch with the plant root, the centrifugal method(3,000 rpm, 20 min) obtained the highest yield. The industrial-scale method, was similar to the processing of sweetpotato starch (tank precipitation method), and was good in quality. The starch granules were mainly spherical with diameters ranging from $5{\sim}16{\mu}$. The density of the starch was 1.535 and amylose content was about 26.7%. The X-ray diffraction pattern showed that the granules were of the B-type. The blue value of starch, amylose and amylopectin was 0.46, 0.80 and 0.18, respectively. The starch contained 0.05% ash, 0.35% crude protein and 34 mg% phosphorus. and had an inital pasting temperature of $63.5^{\circ}C$. The color intensity of the starch which iodine gave rise to absorption maxima at 670nm. The starch paste showed high stability during cold storage at $5^{\circ}C$.

• Applied Biological Chemistry
• /
• v.34 no.1
• /
• pp.14-20
• /
• 1991

Changes in fruit quality and some components of Unshiu orange(Citrus Unshiu Marc. Hayashi) stored at $2^{\circ}C$ in air or a controlled atmosphere(CA, $O_2$ 10%, $CO_2$ 2%) for 111 days were studied. The incidence of rot fruits was higher in air(12.7%) than in CA condition(3.9%). The appearance of the fruits was better in CA condition than in air. There was no significant difference in the weight loss of whole fruits between both storage conditions. The ratio of the flesh weight In whole fruits under CA condition was slightly lower than those in air until 62 days of storage, while it showed no rapid decrease in the later period of storage. Under both storage conditions, the Brix in the flesh increased in the early Period of storage and then decreased slowly, while the free acid contents decreased gradually during storage. In comparison with the fruits stored in air, those under CA condition showed lower total sugar content. The sugar in the flesh of the fruits is composed of sucrose, fructose and glucose. The content of total sugar as well as each sugar showed no distinct difference under both storage conditions. In the flesh of the fruits, citric acid comprised about 90% of the organic acid and malic acid the second abundant acid. During storage, the contents of citric, malic and oxalic acid decreased. Significant difference in the decreasing rate of total organic acid between both stnrage conditions was not found. From the above results, it might be considered that CA could be applied lot the storage of Unshiu orange grown on Cheju