• Journal of Multimedia Information System
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• v.6 no.3
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• pp.155-164
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• 2019

We intended to confirm that microwave attenuation by tree leaves is strongly linked to water content in leaves. We sampled natural broadleaves, including Japanese cinnamon, and investigated their effects on the microwave (3 to 20 GHz) frequency characteristics using a network analyzer. Experiments determined that microwave attenuation by foliage increases as a linear function of frequency per unit weight (gram). As the frequency increases, the spatial resolution increases, but the phase difference (imaginary component) increases. So we solved the dispersion of phase difference by sweeping the frequency and taking the intermediate value. Based on these experimental results, we developed a microwave scanner on 10Ghz to describe foliage moisture as a image and to enable assessments of leaf condition. Photosynthesis is the process whereby plants synthesize oxygen and sugars from carbon dioxide and water, thereby converting light energy into chemical energy. Since water is a major parameter of photosynthesis, the quantity of water accumulated inside a leaf reflects leaf health. The equipment described here and related microwave technologies will help assess the capacity of leaves to absorb atmospheric carbon dioxide.

• Food Science and Preservation
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• v.7 no.2
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• pp.189-194
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• 2000

To study the potential of the Zanthoxylum schinifolium and Z. piperitum leaves, as raw materials for functional food and medicine, apart from male and female, chemical components were carried out. Among general components of sancho and chopi leaves, moisture and crude protein were higher sancho leaf than chopi leaf, but total sugar and crude fat were higher chopi leaf than sancho leaf and the components of major minerals were K, Ca, Mg and Na. Among free sugars, glucose(0.24% and 0.21%) and sucrose(0.19% and 0.27%) were the highest contents in sancho and chopi leaves(male and female), respectively. The organic acid were isolation and identification as malic acid and citric acid, citric acid is higher than malic acid. The total amino acid of sancho and chopi leaves contained proline and glutamic acid in male and female sancho and female chopi leaves, glutamic acid and aspartic acid in male chopi leaf highly in order. The fatty acid contents of four samples were high 15.16%, 9.76%, 8.78% and 9.29% of linolenic acid, respectively. Among many volatile compounds, limonene(13.25% and 19.16%) and citronellal(34.37% and 29.66%) were predominant flavor compounds in sancho and chopi leaves(male and female), respectively.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3629-3634
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• 2013

In this study, an improved method for the quantitative analysis of ginkgolic acids (GAs) in Ginkgo biloba leaf extract was developed. The samples were extracted with a mixture of chloroform and 50 % ethanol, after which the chloroform extract was dried and reconstituted in methanol. GAs with 13:0, 15:1, and 17:1 in the extract were successfully separated within 40 min and determined with high throughput performance using an online column-switching HPLC method using an SP column C8 SG80 ($4.6{\times}150mm$, $5{\mu}m$) and a Cadenza 5CD C18 column ($4.6{\times}150mm$, $3{\mu}m$). The developed HPLC method was validated for Ginkgo biloba leaf extract. The validation parameters were specificity, linearity, precision, accuracy, and limits of detection and quantitation (LODs and LOQs, respectively). It was found that all of the calibration curves showed good linearity ($r^2$ > 0.9993) within the tested ranges. The LODs and LOQs were all lower than $0.04{\mu}g/mL$. The established method was found to be simple, rapid, and high throughput for the quantitative analysis of GAs in ten commercial Ginkgo biloba leaf extract and dietary supplements. The samples were also analyzed in LC-electrospray ionization (ESI) tandem mass spectrometry (MS/MS) - multiple-ion reaction monitoring (MRM) mode to confirm the identification results that were obtained by the column switching HPLC-DAD method. The developed method is considered to be suitable for the routine quality control and safety assurance of Ginkgo biloba leaf extract.

• Biomaterials and Biomechanics in Bioengineering
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• v.4 no.1
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• pp.21-32
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• 2019

Eggshell is a waste material after the usage of egg. In this work, biowaste chicken eggshells were used for preparing carbonated hydroxyapatite (HA) nanoparticles of high purity through aqueous precipitation method at room temperature. The eggshell-derived HA will be a cost-effective bioceramics for biomedical applications and an effective material-recycling technology. Additionally, mulberry leaf extract was used as a template to regulate the morphology, size and crystallinity of HA, and the effects of pH value were also examined. Characterization of the samples was performed by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Scanning electron microscopy (SEM) was used to determine the size, shape and morphology of HA. The results indicate that only one phase of HA were synthesized in the both absence and presence of mulberry leaf extract at pH of 7 and above, while DCPD or DCPA/DCPD phase was observed at pH 4 condition. The crystallite sizes of the HA samples obviously decreased when adding mulberry leaf extract as a template, while they decreased gradually as the solution pH levels increased. With increasing pH level from 7 to 14, the rod-like HA nanoparticles gradually changed to spherical shape at pH 14. Note that, the obtained product is Mg and Sr containing A- and B-type carbonate HA at alkaline pH and it can be a potential material for biomedical applications.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.360-367
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• 2020

BACKGROUND: The productivity and quality of blueberry (Vaccinium ashei Reade) greatly depend on the number of fruits in a plant. Especially, fruit set more than appropriate number negatively affects productivity and marketability due to the increased number of small fruits and delayed harvest time. This study was conducted to investigate proper timing and concentration for applying chemical blossom thinners such as ammonium thiosulfate (ATS) and UREA. METHODS AND RESULTS: ATS at 1.25% and 1.50%, and UREA at 6% and 8% were applied in four developmental stages, bud swell, pink bud, full bloom and petal fall. Fruit thinning rate was calculated based on the number of fruits harvested divided by that of flowers before applying blossom thinners. Ratios of leaf to flower and leaf to fruit were calculated based on the number of fully developed leaves in 25 days after full blossom divided by that of flowers or fruits, respectively. Chemical injury of leaves was investigated by calculating the number of leaves with chemical injury divided by the total number of leaves. Fruit thinning rates were 48% and 66% for UREA treatments at 6% and 8%, respectively, and 49% and 62% for ATS treatments at 1.25% and 1.50%, respectively, in the full bloom stage. In the petal fall stage, fruit thinning rates were 18% and 24% for UREA treatments at 6% and 8%, respectively, and 49% and 35% for ATS treatments at 1.25% and 1.50%, respectively. Leaf to fruit ratio (L/FR) increased by 109% and 188% compared to leaf to flower ratio in ATS treatments at 1.25% and 1.50%, respectively, and L/FR increased 93 and 196% in UREA treatments at 6% and 8%, respectively, in the full bloom stage. In the petal fall stage, leaf to fruit ratio increased by 60% to 100% in ATS treatments, but did not significantly differ from the control in UREA treatments. Fruit harvest was delayed in all treatments of all developmental stages except for 1.5% ATS and 6% UREA treatments at the petal fall stage, whose fruit harvest was two or three days faster than the control. CONCLUSION: The application of ATS and UREA for blossom thinning should be in the petal fall and full bloom stages for early and late harvest, respectively. Considering chemical injury, integrated harvesting and fruit size, however, it is appropriate to apply ATS at 1.5% in the petal fall stage to increase fruit productivity and quality in blueberry.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.2
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• pp.5-15
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• 2022

In this study, heated tobacco biomass was prepared as an active material for supercapacitor device. Retrieved tobacco leaf from the heated tobacco was carbonized at various temperature(800/850/950℃). Carbonized tobacco leaf material synthesized at 850℃ exhibited the highest C/O ratio, indicating the finest carbon quality. In addition, polypyrrole was coated onto the carbonized leaf material for increasing the electrochemical performance via low-temperature polymerization method. As-synthesized carbonized leaf material at 850℃(CTL-850)-based electrode and polypyrrole-coated carbonized leaf material(CTL-850/PPy)-based electrode displayed outstanding specific capacitances of 100.2 and 155.3F g^-1 at 1 A g^-1 with opertaing window of -1.0V and 1.0V. Asymmetric supercapacitor device, assembled with CTL-850 as the negative electrode and CTL-850/PPy as the positive electrode, manifested specific capacitance of 31.1F g^-1(@1 A g^-1) with widened operating voltage window of 2.0V. Moreover, as-prepared asymmetric supercapacitor device was able to lighten up the RED Led (1.8V), suggesting the high capacitance and extension of operating voltage window. The result of this research may help to pave the new possibility toward preparing the effective energy storage device material recycling the biomass.

• Journal of Applied Biological Chemistry
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• v.56 no.2
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• pp.113-117
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• 2013

Ten major residual biogenic amines including toxic histamine and tyramine were investigated in the plant-based minor Korean fermented food. From the analyses of pickled vegetables, fermented vegetable extracts, fermented tea, black garlic and herbal rice wines, more than 100 mg/kg of histamine were found in pickled soy leaf and pickled mulberry leaf, and also over 1,000 mg/kg of total biogenic amines were found in pickled soy leaf. No sample was found over in black garlic, fermented tea, fermented vegetable extracts and herbal rice wine, less than 100 mg/kg of histamine and/or 1,000 mg/kg of total biogenic amines were observed. Interestingly, all the tested rice wines were found to be over 100 mg/kg of agmatine residue.

• Korean Chemical Engineering Research
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• v.48 no.1
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• pp.98-102
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• 2010

Magnolia kobus leaf extract was used for the synthesis of bimetallic Au core-Ag shell nanoparticles. Gold seeds and silver shells were formed by first treating aqueous solution of $HAuCl_4$ and then $AgNO_3$ with the plant leaf extract as reducing agent. UV-visible spectroscopy was monitored as a function of reaction time to follow the formation of bimetallic nanoparticles. The synthesized bimetallic nanoparticles were characterized with transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS), and X-ray photoelectron spectroscopy(XPS). TEM images showed that the bimetallic nanoparticles are a mixture of plate(triangles, pentagons, and hexagons) and spherical structures. The atomic Ag contents of the bimetallic Au/Ag nanoparticles determined from EDS and XPS analysis were 34 and 65 wt%, respectively, suggesting the formation of bimetallic Au core-Ag shell nanostructure. This core-shell type nanostructure is expected to have potential for application in surface enhanced Raman spectroscopy and in the sensitive detection of biomolecules.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.40-47
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• 1989

To elucidate the relationship of the Quality of aromatic tobacco to their chemical constituents, certain chemical components and leaf Quality by price were compared among leaves produced, 1) under 4 different light intensities during maturing stage in field, 2) under 4 different temperature of 20$^{\circ}C$. 25$^{\circ}C$. 30$^{\circ}C$ and control of l8-22-28$^{\circ}C$ in phytotron. As the light intensity decreased chlorophyll content of harvested leaves increased, but specific leaf weight and Quality of cured leaves lowered. The content of sugar. pet. ether exts. and volatile organic acids decreased, but total nitrogen, nicotine, ash and pH increased as the .light intensity decreased. As the growth temperature increased days to flower was shortened and the growth was decreased without significant difference in leaf Quality. With higher growth temperature the content of nitrogen, ash and pH increased, but sugar decreased with no difference in pet. ether exts., volatile organic acids and volatile neutral content. Several Quality indices were disscussed for the Quality evaluation of aromatic leaves for two groups, respectively.

• Journal of Plant Biology
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• v.17 no.1
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• pp.15-21
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• 1974

The most commonly grown economical and flue-cured tobacco cultivar Yellow Special A was used in pot-culture tests in order to study Ethrel (2-chloroethyl phosponic acid) effects on accelerating maturity of tobacco leaves in relation to the most adequate level of the chemical useful for field growing, nitrogen level in soil for the most pronounced response, and the most suitable spray period during the growth stages of pre-, post- and topping periods. The following conclusions, thus, were obtained from the present studies; 1. 500ppm Ethrel spray was reconfirmed to be adequate in the practical applications, although the extent of yellow-ripening of tobacco leaves was increased as the Ethrel level increased. The highest leevel treated resulted in causing chemically damaged lesions on leaves and early defoliation. 2. Ethrel-treated leaves showed deeper yellowish tinge to them than those without treatment, while different levels of the chemcial had less influence on the tinge. 3. An adequate level of nitrogen supply to plants favored the Ethrel response, whereas either very low or high level of nitrogen in the soil lowered the chemical effect on accelerating the yellow-ripening. When carbohydrates versus total nitrogen ratio became relatively high, the condition brought out some outstanding Ethrel effects. 4. Chlorophyll level of leaves increased as soil applications of nitrogen level increased, and that also increased carotenoid level of the tobacco leaves. Ethrel-treated leaves showed deeper orange tinge than those without treatment, while the highest level of nitrogen application showed the deepest orange tinge to tobacco leaves. 5. Pre-topping treatment (12 days before topping and flowering) resulted in almost no Ethrel response, and that treatment right on the day of topping, showed response of yellow-leaf ripening at nearly bottom-half leaves of a tobacco plant. The post-topping treatment (12 days after topping) made plants showing full response of Ethrel from bottom to the top leaves of tobacco plant in accelerating the leaf maturity. 6. The extent of Ethrel responses on accelerating yellow-ripening of tobacco leaves was discussed for the modifying influences brought about by certain environmental factors. Discussions were also made about the possible practical applications (particularly for pre-rice planting) and quality difference that may be caused by such growth environments.