• ALGAE
• /
• v.32 no.1
• /
• pp.75-86
• /
• 2017

Polysaccharides of marine algae exhibit different structural characteristics and interesting biological functions. In this study, crude polysaccharides (CP) of eleven Sri Lankan marine algae obtained through hot water extraction and ethanol precipitation were investigated for DPPH, alkyl, and hydroxyl radical scavenging activities using electron spin resonance spectrometry and for intracellular reactive oxygen species scavenging activity in the Chang liver cell line. Characterization of CPs was done by Fourier transform infrared (FTIR) spectroscopy and by analysis of the monosaccharide composition. Time-dependent density functional theory quantum-chemical calculations at the RB3LYP/6-31G(d,p) level for constructed dimeric units of the corresponding polysaccharides were used to resolve the FTIR spectra. CPs from Chnoospora minima showed the highest DPPH and alkyl radical scavenging activities and higher intracellular reactive oxygen species scavenging effects for both AAPH and $H_2O_2$ induced ROS production in "Chang" cells. The major polysaccharide constituent in C. minima CP was identified as fucoidan and it displayed a higher sulfate content. The degree of sulfation of these polysaccharides suggests a positive correlation with the observed antioxidant properties.

• Journal of Ginseng Research
• /
• v.45 no.4
• /
• pp.473-481
• /
• 2021

Background: Mitochondrial dysfunction is one of the significant reasons for Alzheimer's disease (AD). Ginsenosides, natural molecules extracted from Panax ginseng, have been demonstrated to exert essential neuroprotective functions, which can ascribe to its anti-oxidative effect, enhancing central metabolism and improving mitochondrial function. However, a comprehensive analysis of cellular mitochondrial bioenergetics after ginsenoside treatment under Aβ-oxidative stress is missing. Methods: The antioxidant activities of ginsenoside Rb₁, Rd, Re, Rg₁ were compared by measuring the cell survival and reactive oxygen species (ROS) formation. Next, the protective effects of ginsenosides of mitochondrial bioenergetics were examined by measuring oxygen consumption rate (OCR) in PC12 cells under Aβ-oxidative stress with an extracellular flux analyzer. Meanwhile, mitochondrial membrane potential (MMP) and mitochondrial dynamics were evaluated by confocal laser scanning microscopy. Results: Ginsenoside Rg₁ possessed the strongest anti-oxidative property, and which therefore provided the best protective function to PC12 cells under the Aβ oxidative stress by increasing ATP production to 3 folds, spare capacity to 2 folds, maximal respiration to 2 folds and non-mitochondrial respiration to 1.5 folds, as compared to Aβ cell model. Furthermore, ginsenoside Rg1 enhanced MMP and mitochondrial interconnectivity, and simultaneously reduced mitochondrial circularity. Conclusion: In the present study, these results demonstrated that ginsenoside Rg₁ could be the best natural compound, as compared with other ginsenosides, by modulating the OCR of cultured PC12 cells during oxidative phosphorylation, in regulating MMP and in improving mitochondria dynamics under Aβ-induced oxidative stress.

• BMB Reports
• /
• v.55 no.8
• /
• pp.401-406
• /
• 2022

Ahnak, a large protein first identified as an inhibitor of TGF-β signaling in human neuroblastoma, was recently shown to promote TGF-β in some cancers. The TGF-β signaling pathway regulates cell growth, various biological functions, and cancer growth and metastasis. In this study, we used Ahnak knockout (KO) mice that underwent a 70% partial hepatectomy (PH) to investigate the function of Ahnak in TGF-β signaling during liver regeneration. At the indicated time points after PH, we analyzed the mRNA and protein expression of the TGF -β/Smad signaling pathway and cell cycle-related factors, evaluated the cell cycle through proliferating cell nuclear antigen (PCNA) immunostaining, analyzed the mitotic index by hematoxylin and eosin staining. We also measured the ratio of liver tissue weight to body weight. Activation of TGF-β signaling was confirmed by analyzing the levels of phospho-Smad 2 and 3 in the liver at the indicated time points after PH and was lower in Ahnak KO mice than in WT mice. The expression levels of cyclin B1, D1, and E1; proteins in the Rb/E2F transcriptional pathway, which regulates the cell cycle; and the numbers of PCNA-positive cells were increased in Ahnak KO mice and showed tendencies opposite that of TGF-β expression. During postoperative regeneration, the liver weight to body weight ratio tended to increase faster in Ahnak KO mice. However, 7 days after PH, both groups of mice showed similar rates of regeneration, following which their active regeneration stopped. Analysis of hepatocytes undergoing mitosis showed that there were more mitotic cells in Ahnak KO mice, consistent with the weight ratio. Our findings suggest that Ahnak enhances TGF-β signaling during postoperative liver regeneration, resulting in cell cycle disruption; this highlights a novel role of Ahnak in liver regeneration. These results provide new insight into liver regeneration and potential treatment targets for liver diseases that require surgical treatment.

• Biomolecules & Therapeutics
• /
• v.30 no.6
• /
• pp.593-602
• /
• 2022

The human papillomavirus (HPV)-18 E7 (E7) oncoprotein is a major transforming protein that is thought to be involved in the development of cervical cancer. It is well-known that E7 stimulates tumour development by inactivating pRb. However, this alone cannot explain the various characteristics acquired by HPV infection. Therefore, we examined other molecules that could help explain the acquired cancer properties during E7-induced cancer development. Using the yeast two-hybrid (Y2H) method, we found that the Elk-1 factor, which is crucial for cell proliferation, invasion, cell survival, anti-apoptotic activity, and cancer development, binds to the E7. By determining which part of E7 binds to which domain of Elk-1 using the Y2H method, it was found that CR2 and CR3 of the E7 and parts 1-206, including the ETS-DNA domain of Elk-1, interact with each other. As a result of their interaction, the transcriptional activity of Elk-1 was increased, thereby increasing the expression of target genes EGR-1, c-fos, and E2F. Additionally, the colony forming assay revealed that overexpression of Elk-1 and E7 promotes C33A cell proliferation. We expect that the discovery of a novel E7 function as an Elk-1 activator could help explain whether the E7 has novel oncogenic activities in addition to p53 inactivation. We also expect that it will offer new methods for developing improved strategies for cervical cancer treatment.

• Proceedings of the Optical Society of Korea Conference
• /
• 2000.08a
• /
• pp.74-75
• /
• 2000

The past few decades have witnessed the development of very robust technique, known as magneto-optical trap(MOT), for cooling and trapping of neutral atoms using lasers and magnetic fields. This technique can easily produce cooled atoms to a temperature range of nano-kelvin $s^{(1)}$ . These laser cooled and trapped atoms have found applications in various fields, such as ultrahigh resolution spectroscopy, precision atomic clocks, very cold atomic collision physics, Bose-Einstein Condensation, the Atom laser, etc. Particularly, a few isolated atoms of very low temperature are needed in the cavity QED studies in the optical regime. One can obtain such atoms from a MOT using the atomic fountain technique. The widely used technique for atomic fountain is, first to cool and trap the neutral atoms in MOT. And then launch them in the vertical (1, 1, 1) direction with respect to cooling beams, using moving molasses technique. Recently, this technique combined with the cavity-QED has opened an active area of basic research. This way atoms can be strongly coupled to the optical radiation in the cavity and leads to various new effects. Trapping of single atom after separating it from MOT in the high Q-optical cavity is actively initiated presentl $y^{(2.3)}$. This will help to sharpen our understanding of atom-photon interaction at quantum level and may lead to the development of single-atom laser. Our efforts to develop an $^{85}$ Rb-atomic fountain is in progress. (omitted)

• Journal of Ginseng Research
• /
• v.38 no.3
• /
• pp.180-186
• /
• 2014

Background: This study evaluated changes in ginsenoside compositions and antioxidant activities in hydroponic-cultured ginseng roots (HGR) and leaves (HGL) with heating temperature. Methods: Heat treatment was performed at temperatures of $90^{\circ}C$, $110^{\circ}C$, $130^{\circ}C$, and $150^{\circ}C$ for 2 hours Results: The ginsenoside content varied significantly with heating temperature. The levels of ginsenosides Rg1 and Re in HGR decreased with increasing heating temperature. Ginsenosides F2, F4, Rk3, Rh4, Rg3 (S form), Rg3 (R form), Rk1, and Rg5, which were absent in the raw ginseng, were formed after heat treatment. The levels of ginsenosides Rg1, Re, Rf, and Rb1 in HGL decreased with increasing heating temperature. Conversely, ginsenosides Rk3, Rh4, Rg3 (R form), Rk1, and Rg5 increased with increasing heating temperature. In addition, ginsenoside contents of heated HGL were slightly higher than those of HGR. The highest extraction yield was 14.39% at $130^{\circ}C$, whereas the lowest value was 10.30% at $150^{\circ}C$ After heating, polyphenol contents of HGR and HGL increased from 0.43 mg gallic acid equivalent/g (mg GAE eq/g) and 0.74 mg GAE eq/g to 6.16 mg GAE eq/g and 2.86 mg GAE eq/g, respectively. Conclusion: Antioxidant activities of HGR and HGL, measured by 1,1-diphenyl-2-picrylhydrazyl and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging ability, increased with increasing heating temperature. These results may aid in improving the biological activity and quality of ginseng subjected to heat treatments.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.5
• /
• pp.1126-1135
• /
• 2023

Nine microbial strains were isolated from the byproduct of ginseng processing and field of ginseng cultivation. Two strains among them were confirmed. Phylogenetic analysis of these 𝛽-Glucosidase strains confirmed that strain GYP-1 belongs to the Rhodotorula and strain GYP-3-3 belong to genus Brachybacterium. Rhodotorula sp. GYP-1 was finally selected due to its high biomass production. The 𝛽-Glucosidase activity of Rhodotorula sp. GPY-1 was assessed at 30 ℃, and Higher than 70% of the enzyme activity was maintained at the temperature range of 20-40℃. Although the optimum pH for the highest enzyme activity was pH 5.0, the enzyme was stable throughout the pH range of 5.0-8.0. In addition, Rhodotorula sp. demonstrated antifungal activity against the ginseng root rot disease caused by Botrytis.

• Journal of the Korean earth science society
• /
• v.21 no.5
• /
• pp.595-610
• /
• 2000

This study has been designed to elucidate the petrography and geochemical characteristics of the volcanic rocks and focused on petrogenesis and tectonic environment of the Bokyeongsa volcanics in the northeast Gyeongsang Basin. The Bokyeongsa volcanics consist of the Naeyeonsan tuff which include rock fragment plagioclase, quartz and hornblende and pumice showing welded structures, and felsite. According to the petrochemical data, the Naeyeonsan tuff and felsite are in the range of 68${\sim}$71wt% and 77wt% SiO$_2$ content respectively. The Naeyeonsan tuff belongs to dacite/rhyodacite, and felsite to rhyolite. These volcanics rocks belong to the calc-alkaline rock series on the TAS diagram and the AFM diagram. The variations of major elements of the volcanic rocks show that contene of TiO$_2$, Al$_2$ O$_3$, FeO$^T$, MnO, MgO, CaO are inversely proportional to those of SiO$_2$, but contents of K$_2$O are positively. They represent differentiation trend of calc-alkaline rocks series. In spider disgram of MORB-normalized trace element partterns, contents of K, Rb, Th and Ta are relatively high, but those of Nb, Zr, Hf, Ti, Y and Yb are nearly similar to MORB. In the chondrite-normalized REE patterns, light REEs are more enriched than heavy REEs. The trace element composition and REE patterns suggest that they are typical island-arc calc-akaline volcanic rocks formed in the tectonomagmatic environment of subduction zone under continental margin.

• Journal of Bio-Environment Control
• /
• v.27 no.1
• /
• pp.54-63
• /
• 2018

Red and blue lights are effective wavelengths for photosynthesis in plants. In this study, we determined the effects of various combined ratios of red to blue LEDs on the quality of cherry tomato seedlings prior to transplantation, and their subsequent effects on the yield and quality of tomato fruits after transplanting. Two-week-old cherry tomato seedlings (Solanum lycopersicum cv. 'Cuty') were cultivated under various combined ratios of red (R; peak wavelength 655 nm) to blue (B; 456 nm) LEDs [red:blue = 41:59 (59B), 53:47 (47B), 65:35 (35B), 74:26 (26B), 87:13 (13B), or 100:0 (0B)] and fluorescent lamps and raised for 27 days. The cherry tomato seedlings were subsequently transplanted into a venlo-type greenhouse and cultivated for 75 days. At the seedling stage, the shoot fresh weight of seedlings in all RB combined treatments, except 0B and 59B, was higher than that of the control after 27 days of LED treatment. Shoot dry weight and leaf area also showed trends similar to that of shoot fresh weight. The stem length was significantly higher in 13B, 26B, and 35B treatments compared with the control and other treatments. In particular, the stem length of 26B plants was approximately 3.2 times longer than that of 59B plants. At 37 days after transplanting, the number of nodes was significantly higher in 26B and 47B plants, and the plant height of 26B plants was significantly higher than that of control and 59B plants. Total fruit yield in 26B plants, which was the highest, was approximately 1.6 and 1.8 times higher than that in control and 59B plants, respectively. Thus, the results of this study indicate that various combined ratios of red to blue LEDs directly affected to the growth of cherry tomato seedlings and may also affect parameters of reproductive growth such as fruit yield after transplantation.

• Journal of Plant Biology
• /
• v.39 no.1
• /
• pp.63-69
• /
• 1996

A hairy root clone of Panax ginseng C.A. Meyer, HRB-15 was cultured iu various conditions with 3 L bubble type bioreactor to enhance both growth and ginsenoside production. The hairy roots were more rapidly grown under the dark condition than under the light condition. However, total amount of ginsenoside of hairy roots cultured under the light for 30 days increased 2 folds as compared with the dark condition and was 1.10% based on 6 ginsenosides. Especially, ginsenoside-Re was significantly increased and some ginsenosides except for ginsenoside-Re was slightly reduced. Also, the growth of hairy roots decreased about 30% as compared with the dark condition. In contrast, addition of sodium acetate led to decreased production of ginsenoside and growth of hairy roots under light condition. The influence of potassium dihydrogenphosphate concentration was examined in MS medium and a 1.25 mM concentration was found to be the most appropriate for growth and ginsenoside production under light condition. Two-step process of hairy roots culture with yeast elicitation or without ammonia in culture medium was developed to enhance growth and giusenoside synthesis. $50\;\mu\textrm{g}$ of yeast elicitor per g of fresh weight showed a synergistic effect on the ginsenoside synthesis of hairy roots on 20 days after culture. At that time, the content of total ginsenoside was 1.15%, while the growth of hairy roots decreased 21 % as compared with the dark condition. In addition, when elimination of ammonia on 20 days after culture, the content of total ginsenoside was 1.26% with significant increment of ginsenoside-Rd (0.27%) in addition to ginsenoside-Re and the growth of hairy roots decreased 10% as compared with the dark condition. In this system, we have demonstrated a unique two-step process of hairy root cultures to maximize biomass and secondary metabolites. It has found possibility to enhance ginsenosides production by growing hairy roots in this method.