• Korean Journal of Plant Resources
• /
• v.22 no.5
• /
• pp.461-466
• /
• 2009

This study was carried out to evaluate the effects of yam (Dioscorea batatas Dence) extracts on the cell viability, growth and nucleus-DNA damage of tobacco cells which were exposed to $\gamma$-radiation stress. The viability and growth of tobacco cells exposed to 20 Gy of radiation stress were effectively recovered by pretreatment of 10 mg/L ethylacetate (EtOAc) yam extract. Pretreatment of EtOAc extract showed 20% higher cell viability and fresh weight growth than that of cells without pretreatment in 20 Gy radiation treated tobacco cells. Nucleus-DNA damage was measured as the ratio of tail length (T) to head length (H) in individual comet image isolated from tobacco cells. The T/H ratio of control-cells and treated-cells at 20 Gy were 1.05 and 1.68, and % head DNA of those cell were 86.7 and 71.3%, respectively, suggesting that nuclei of tobacco cells were severely damaged in the integrity of DNA by the treatment of $\gamma$-radiation. However, pretreatment of MeOH, EtOAc and n-BuOH extracts decreased radiation induced DNA-damage in the tobacco cells, showing T/H ratio of 1.37, 1.01 and 1.10 and % head DNA of 81.5, 87.6 and 88.7%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.2
• /
• pp.154-161
• /
• 2008

Phellinus linteus (PL) has been known to exhibit potent biological activity. The present study was designed to investigate lipase-inhibitory and anti-oxidative activity of the methanol extract and the powder of PL fruiting body. The methanol extract of PL appeared to have the inhibitory activity against pancreatic lipase with an $IC_{50}$ value of $36.3\;{\mu}g/mL$, and the scavenging activity of DPPH radical with an $IC_{50}$ value of $20.1\;{\mu}g/mL$, which was similar to that of vitamin C ($IC_{50}\;18.3\;{\mu}g/mL$). To investigate the lipase-inhibitory and anti-oxidative effect of PL on animal, Sprague-Dawley rats were fed with high-fat diet supplemented with either 2% or 5% PL powder for 8 weeks. Total food intake was significantly increased, but body weight was not changed by PL powder supplementation. However, fecal fat excretion of the experimental groups fed with the PL powder were higher than that of the control group. PL powder showed a decrease in the plasma total cholesterol, LDL-cholesterol, and the hepatic total cholesterol levels. The anti-oxidative enzyme activities were also affected by PL supplementation. Glutathione peroxidase (GSH-Px) in the plasma and liver were significantly increased by 98% and 46% in the 2% PL group, and 99% and 32% in the 5% PL group, respectively. Total superoxide dismutase (T-SOD) activity was not affected by PL supplementation. DNA damage was measured by the comet assay in the lymphocytes collected after 2 weeks, 4 weeks, and 8 weeks of feeding PL supplemented diet. Lymphocyte DNA damage was decreased in the PL supplemented group. Furthermore, PL feeding enhanced the resistance to lymphocyte DNA damage caused by an oxidant challenge with $H_2O_2$.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.187-190
• /
• 2000

Effects of gamma ionizing radiation on recombinant Escherichia coli cells containing stress promoters, recA, fabA, grpE, or katG, fused to luxCDABE originated from Vibrio fischeri were characterized by monitoring transcriptional responses reflected by bioluminescent output. Quantification of gamma-ray intensity may be possible using the recA and fabA promoter fusion since a linear enhancement of bioluminescence emission with increasing gamma-ray intensity was observed. Other strains sensitive to either oxidative stress (DPD2511, katG::luxCDABE) or protein-damaging stress (TV1061, grpE::luxCDABE) were also irradiated by gamma-rays, and resulted in no noticeable bioluminescent output while DPD2794 with recA promoter and DPD2540 with fabA promoter irradiated by the same intensities of gamma-rays gave a significant bioluminescent output. This indicates that the main stresses in the recombinant bacteria caused by ionizing radiation are DNA and membrane-damage, not protein- or oxidative-damage. In addition, in this study, to investigate the relationship between the radiation dose rate and bacterial responses, two recombinant Escherichia coli strains, DPD2794 and GC2, containing lac promoter fused to luxCDABE originating from Photorhapdus luminescences, were used for detecting DNA damage and cellular toxicity under various radiation dose rates. Throughout this study, it was found that these bacteria showed quantitative stress responses to DNA damage and general toxicity caused by gamma rays, depending on the radiation dose rates, indicating that the bacterial stress responses and general toxicity were seriously influenced according to radiation dose rates.

• Journal of Food Hygiene and Safety
• /
• v.13 no.4
• /
• pp.394-399
• /
• 1998

결명자의 주용성분인 노르-루브로푸사린의 함량이 높은 추출물을 얻기 위하여 결명자분말을 0~100%의 에탄올수용액으로 추출하여 고농도의 노르-루브로푸사린을 함유하는 결명자 추출물을 제조하였다. 결명자추출물과 주요 함유성분인 노르-루브로푸사린은 항산화활성과 프리라디칼소거 작용을 나타내었으며, H2O2 유도 세포독성에 대해서도 억제적으로 작용하여 cyto-protective effect를 나타내었다. 또한 DNA crosslinking agent 인 mitomycin C 유도 소핵생성에도 결명자 70% 에탄올추출물과 노르-루브로파사린이 매우 높은 억제활성을 나타내었다. 따라서 결명자 추출물과 노르-루브로푸사린은 산소라디칼들에 의한 산화적 손상 및 DNA 손상 등에 억제적으로 작용하는 기전을 활용하여 항산화성 스트레스를 통한 항노화 , 암예방제로서의 응용가능성이 높은 물질로 판단되었다.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.27 no.1
• /
• pp.77-84
• /
• 2000

Although ferric sulfate has been proposed as an alternative to formocresol in pulpotomy treatment in primary teeth, it has been given little concern regarding its cytotoxicity and mutagenicity. In the present study, we assessed the in vitro genotoxic effect of a ferric sulfate on human gingival fibroblast cell line (HGF-1). DNA damage was evaluated using comet assay (single cell alkaline gel electrophoresis) and obtained the results as follows: 1. A dose-response relationship was found between ferric sulfate concentrations (0 to 5mM) and DNA damages. 2. Above the concentration of 0.1mM, DNA damage was significantly increased than those of the control (p<0.05). 2. At the fixed concentration of 0.05mM, no significant difference was found between exposure time and DNA damage. These findings suggest that ferric sulfate as a pulpotomy agent can induce DNA damage in human gingival fibroblasts.

• Food Science of Animal Resources
• /
• v.25 no.4
• /
• pp.494-499
• /
• 2005

In the present study, we investigate the protective effect of antioxidant strain Lactobacillus gasseri KACC 91155, isolated from Korean infant feces(Obstetrics & Gynecology, Suwon, Korea) on the oxidative stress damage on the Jurkat T cells. To estimate the extent of cellular lipid peroxidation inhibition, MDA(malondialdehyde) production was measured Furthermore, cell viability was detected by the MTT assay, DNA damage was tested by the comet assay. Cell grown in medium with or without L gasseri lysate$(100\~1,000{\mu}g)$ were treated with $H_2O_2,\;Fe^{2+}$ as an oxidative stimulus. From the result obtained, the supplementation of Jurkat T cells with L. gasseri lysate significantly decreased in MDA production (1,250 vs. 835 nmol/mg protein), and DNA damage(31.6 vs. 22.6 tail moment). Also L gasseri increase cell viability against oxidative damage. We concluded that the L. gasseri KACC 91155 showed a protective effect against oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.12
• /
• pp.1628-1632
• /
• 2007

The present study describes the preliminary evaluation of antioxidant activities and antigenotoxic effect of Rhododendron mucromulatum Turcz. flowers (RMF). The samples were prepared by extracting RMF with four different solvents (methanol, ethanol, acetone, and water), and antioxidant properties were evaluated by determining total phenolic contents (TPC), DPPH radical scavenging activity (RSA), and reducing power (RP). Water extract showed the highest total phenol content (328.1 mg/g gallic acid equivalents). Acetone extract showed the most potent RSA and RP. The $IC_{50}$ for RSA and RP in the acetone extract were 78 mg/mL and 454 mg/mL, respectively. The 200 mM $H_2O_2$ induced DNA damage, measured by Comet assay, was inhibited with water, methanol and acetone extract in dose dependent manner in human leukocytes. The inhibition rates were 42, 62, and 52% at the concentrations of 50 mg/mL of water, methanol and acetone extracts, respectively. These results suggest that R. mucromulatum Turcz. has significant antioxidative activity and protective effect against oxidative DNA damage.

• Korean Journal of Poultry Science
• /
• v.50 no.4
• /
• pp.213-229
• /
• 2023

This study aimed to investigate the effects of beak trimming and crossbreeding-combinations on the productive performance and stress response levels of Korean native chickens. The study divided 248 individuals from six crossbreeding-combinations into two groups: one underwent beak trimming, and the other did not. The survival rate, body weight, egg production rate, egg quality, feather damage score, HSP-70 gene expression level, H/L ratio, and intracellular DNA damage rate were measured and analyzed. The results showed that the beak-trimmed group had significantly higher survival rates and hen-housed egg production compared to the non-beak-trimmed group (P<0.05). Feather damage and DNA damage rates were significantly lower in the beak-trimmed group (P<0.05). On the other hand, there were no significant differences between the two groups in adult body weight, hen-day egg production, egg quality, HSP-70 gene expression level, and H/L ratio. Among the crossbreeding-combinations, there were significant differences in survival rate, body weight, feather damage score, egg quality, and DNA damage rate (P<0.05), while egg production rate, HSP-70 gene expression level, and H/L ratio showed no significant differences. There was an interaction between beak trimming and crossbreeding-combinations in some traits. In conclusion, beak trimming in Korean native chickens has a positive impact on productive performance, and in terms of stress response, beak trimming may not act as a stress factor or may even reduce stress after the growing period. Furthermore, there were differences in productive performance and stress response levels among crossbreeding-combinations, but the effects of beak trimming were similar across these combinations.

• Environmental Analysis Health and Toxicology
• /
• v.16 no.1
• /
• pp.17-20
• /
• 2001

The alkaline comet assay, employing a single-cell gel electrophoresis(SCGE), is a rapid, simple and sensitive technique for visualizing and measuring DNA damage leading to strand breakage in individual mammalian cells. The protecting effect of pretreatment with vitamin C and cysteine on the DNA damage of gamma ray was investigated in mice splenic lymphocytes. Vitamin C and cysteine were administered orally for five consecutive days before irradiation. Four week old ICR male mice were irradiated wish 3.5Gy of γ-radiation and were sacrificed 3 days later. Spleens were taken for DNA damage examination by Comet assay and the tail moments of DNA single -strand breaks in tole splenic lymphocytes were evaluated. The results show that pretreatment with vitamin C and cysteine were effective in protecting against DNA damage by gamma ray. Administration of antioxidants like vitamin C and cysteine to mice before irradiation was effective in reducing the tail moment of splenic lymphocytes DNA.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2002.10a
• /
• pp.368-368
• /
• 2002