• Title/Summary/Keyword: Oxidative

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Changes in the constituents and UV-photoprotective activity of Astragalus membranaceus caused by roasting (황기의 볶음 조건에 따른 성분 및 자외선 광보호 활성 변화)

  • Park, Jeong-Yong;Lee, Ji Yeon;Kim, Hyung Don;Jang, Gwi Yeong;Seo, Kyung Hye
    • Journal of Nutrition and Health
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    • v.52 no.5
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    • pp.413-421
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    • 2019
  • Purpose: Astragalus membranaceus (AM) is an important traditional medicinal herb. Pharmacological research has indicated that AM has various physiological activities such as antioxidant, anti-inflammatory, immunoregulatory, anticancer, hypolipidemic, antihyperglycemic, and hepatoprotective activities. The bioactive substances responsible for the physiological activities in AM, including many antioxidant substances, change during the roasting process. This study investigated and compared the changes in the antioxidant constituents of AM caused by roasting. Methods: DPPH (1,1-diphenyl-2-picryl hydrazyl) and $ABTS^+$ (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) radical scavenging activities and their total phenolic content (TPC) were measured. High-performance liquid chromatography (HPLC) analysis was performed to confirm any changes in the isoflavonoids of roasted AM (R-AM),. The cell viability of UVB-induced HDF (Human dermal fibroblast) cells treated with AM and R-AM extracts was investigated. The comet assay was used to examine the inhibitory effects of R-AM extracts on DNA damage caused by oxidative stress. Results: The DPPH and $ABTS^+$ radical scavenging activities were $564.6{\pm}20.9$ and $108.2{\pm}3.1$ ($IC_{50}$ value) respectively, from the 2R-AM. The total phenol content was $47.80{\pm}1.40mg$ GAE/g from the 1R-AM. The values of calycosin and formononetin, which are the known isoflavonoid constituents of AM, were $778.58{\pm}2.72$ and $726.80{\pm}3.45{\mu}g/g$ respectively, from the 2R-AM. Treatment of the HDF cells with R-AM ($50{\sim}200{\mu}g/mL$) did not affect the cell viability. Furthermore, the R-AM extracts effectively protected against UVB-induced DNA damage. Conclusion: The findings of this study indicate that R-AM increases its isoflavonoid constituents and protects against UVB-induced DNA damage in HDF cells.

Role of Dual Oxidase 2 in Reactive Oxygen Species Production Induced by Airborne Particulate Matter PM10 in Human Epidermal Keratinocytes (인간 표피 각질형성세포에서 대기 미립자 물질 PM10에 의해 유도되는 반응성 산소종의 생성에서 Dual oxidase 2의 역할)

  • Seok, Jin Kyung;Choi, Min A;Ha, Jae Won;Boo, Yong Chool
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.1
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    • pp.57-67
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    • 2019
  • Particulate matters with a diameter of < $10{\mu}m$ (PM10) exert oxidative stress and inflammatory events in various organs. The purpose of this study was to examine the molecular mechanism of reactive oxygen species (ROS) production induced by PM10 in the human epidermal keratinocytes (HEKs). When cultured HEKs were exposed to PM10, ROS production was induced and it was inhibited by apocynin, an antioxidant. The mRNA expression of NADPH oxidase (NOX) family was analyzed in order to examine their role in PM10-induced ROS production. PM10 increased the mRNA expression of NOX1, NOX2, dual oxidase (DUOX) 1 and DUOX2. HEKs expressed DUOX1 and DUOX2 at higher levels compared to other NOXs. The mRNA expression of dual oxidase maturation factors, DUOXA1 and DUOXA2, was also increased by PM10. We examined whether these calcium-dependent enzymes, DUOX1 and DUOX2, mediate the PM10-induced ROS production. A selective intracellular calcium chelator, BAPTA-AM, attenuated ROS production induced by PM10 or calcium ionophore A23187. The small intereference RNA (siRNA)-mediated down-regulation of DUOX2, but not DUOX1, attenuated the ROS production induced by PM10. PM10 increased the expression of inflammatory cytokines such as interleukin $(IL)-1{\beta}$, IL-6, IL-8 and interferon $(IFN)-{\gamma}$. SiRNA-mediated down-regulation of DUOX2 suppressed the PM10-induced expression of $IFN-{\gamma}$ but not other cytokines. This study suggests that DUOX2 plays a crucial role in ROS production and inflammatory response in PM10-exposed keratinocytes.

Differences in Urine Cadmium Associations with Renal Damage Markers According to the Adjustment with Specific Gravity or Urinary Creatinine (요비중 또는 크레아티닌 보정에 따른 요중 카드뮴과 신장손상지표와의 관련성 비교)

  • Kim, Yong-Dae;Eom, Sang-Yong;Yim, Dong-Hyuk;Kwon, Soon Kil;Park, Choong-Hee;Kim, Guen-Bae;Yu, Seung-Do;Choi, Byung-Sun;Park, Jung-Duck;Kim, Heon
    • Journal of Life Science
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    • v.29 no.2
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    • pp.265-271
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    • 2019
  • In general, specific gravity (SG) and urinary creatinine (CR) have been used to adjust urinary cadmium (Cd) concentrations. However, the validity of correction methods has been controversial. We compared the two adjustments to evaluate associations between urinary Cd and various renal damage markers and to evaluate the relationship between urinary Cd concentration and renal disease markers, such as estimated glomerular filtration rate (eGFR), in a relatively large general population sample. Among the 1,086 volunteers who were enrolled in this study, 862 healthy volunteers who did not have kidney disease were included in the final analysis. Urinary Cd, malondialdehyde (MDA), and N-acetyl-${\beta}$-D-glucosaminidase (NAG) concentrations were measured, the creatinine-based eGFR was calculated, and the relationships between these markers were subsequently analyzed. This study showed the use of urinary Cd concentration adjusted with SG rather than with urinary creatinine may be appropriate in studies evaluating renal function based on Cd exposure. Urinary Cd concentration adjusted with SG had a positive correlation with urinary MDA levels and a negative correlation with eGFR. This relationship was relatively stronger in women than in men. This study showed that urinary Cd level was associated with decreased eGFR in the general population, and oxidative stress was likely to act as an intermediator in this process. These results suggest that eGFR can be a very good indicator of kidney damage caused by Cd exposure in the general population.

Protective Effect of the Ethyl Acetate-fraction of Methanol Extract of Ophiophogon japonicus on Amyloid beta Peptide-induced Cytotoxicity in PC12 Cells (소엽맥문동-에틸아세테이트 분획물의 아밀로이드 베타단백질-유발 세포독성에 대한 억제 효능)

  • Moon, Ja-Young;Kim, Eun-Sook;Choi, Soo-Jin;Kim, Jin-Ik;Choi, Nack-Shik;Lee, Kyoung;Park, Woo-Jin;Choi, Young-Whan
    • Journal of Life Science
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    • v.29 no.2
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    • pp.173-180
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    • 2019
  • Amyloid ${\beta}$-protein ($A{\beta}$) is the principal component of senile plaques characteristic of Alzheimer's disease (AD) and elicits a toxic effect on neurons in vitro and in vivo. Many environmental factors, including antioxidants and proteoglycans, modify $A{\beta}$ toxicity. It is worthwhile to isolate novel natural compounds that could prove therapeutic for patients with AD without causing detrimental side effects. In this study, we investigated the in vitro neuroprotective effects of the ethyl acetate fraction of methanol extract of Ophiophogon japonicas (OJEA fraction). We used an MTT reduction assay to detect protective effects of the OJEA fraction on $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells. We also used a cell-based ${\beta}$-secretase assay system to investigate the inhibitory effect of the OJEA fraction on ${\beta}$-secretase activity. In addition, we performed an in vitro lipid peroxidation assay to evaluate the protective effect of the OJEA fraction against oxidative stress induced by $A{\beta}_{25-35}$ in PC12 cells. The OJEA fraction had strong protective effects against $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells and was strongly inhibitory to ${\beta}$-secretase activity, which resulted in the attenuation of $A{\beta}$ generation. In addition, the OJEA fraction significantly decreased malondialdehyde (MDA) content, which is induced by the exposure of PC12 cells to $A{\beta}_{25-35}$. Our results suggested that the OJEA fraction contained active compounds exhibiting a neuroprotective effect on $A{\beta}$ toxicity.

Single Dose Oral Toxicity Test of Water Extract of Corni Fructus in ICR Mice (ICR 마우스를 이용한 산수유 건피 추출물의 단회 경구투여 독성시험)

  • Hwang-Bo, Hyun;Kwon, Da Hye;Kim, Min Young;Ji, Seon Yeong;Choi, Eun Ok;Kim, Sung Ok;Jeong, Ji-Suk;Hong, Su Hyun;Choi, Sung Hyun;Park, Cheol;Choi, Yung Hyun
    • Journal of Life Science
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    • v.29 no.1
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    • pp.112-117
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    • 2019
  • Herbal medicines are widely used as therapeutic products in many countries. Corni fructus (CF), the dried ripe sarcocarp of Cornus officinalis Sieb. et Zucc (Cornaceae), has been used for thousands of years in traditional medicine and has been reported to be effective for the prevention and treatment of various diseases, such as kidney diseases and diabetes. Recent research on CF has documented a wide spectrum of therapeutic properties, which include anti-inflammatory, ant-oxidative, immunomodulatory, and anti-cancer effects. However, there is no information on its safety. Therefore, in this study, the toxicity of water extract of CF to ICR mice was investigated. The mice received a single dose of water extract of CF (1,000, 2,000, and 5,000 mg/kg of body weight) via the oral route. Mortality, clinical signs, body weight changes, gross findings, and weights of the principal organs after 14 d were then assessed. The results revealed no adverse effects of CF as determined by clinical signs, body weights, or organ weights and no gross pathological findings in any of the treatment groups. These results suggest that the 50% lethal dose and approximated lethal dose of CF extract is over 5,000 mg/kg. The findings provide scientific evidence for the safety of CFs.

Characterization of Repeated Deactivation and Subsequent Re-activation of Photocatalyst Used in Two Alternatively-operating UV/photocatalytic Reactors of Waste-air Treating System (교대로 운전되는 두 개의 UV/광촉매반응기로 구성된 폐가스 처리시스템에서의 광촉매의 비활성화 및 재생 특성)

  • Lee, Eun Ju;Chung, Chan Hong;Lim, Kwang-Hee
    • Korean Chemical Engineering Research
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    • v.59 no.4
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    • pp.584-595
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    • 2021
  • In this study, the correlation between operating stages of waste air-treating system composed of two alternatively-operating UV/photocatalytic reactors, and the deactivation of photocatalyst used in each operating stage, was investigated by instrumental analysis thereon. The repeated deactivation and subsequent re-generation of photocatalyst used in the waste air treating system of previous investigation performed by Lee and Lim (Korean Chem. Eng. Research, 59(4), 574-583(2021)), were characterized on virgin photocatalyst-carrying porous SiO2 media (A4), used photocatalyst-carrying porous SiO2 media (A1, A2 and A3) collected from the corresponding photocatalytic reactor upon 1st, 2nd, and 3rd run, respectively, regenerated photocatalyst-carrying porous SiO2 media upon 1 time-run (AD1) and 3 times regenerated photocatalyst-carrying porous SiO2 media upon 3 time-runs (AD3) by instrumental analysis including BET analysis, SEM, XPS, SEM-EDS and FT-IR. As a result, the proper regeneration-temperature for deactivated photocatalyst to be regenerated several times (more than 3 times), was suggested below 200 ℃. Such temperature of deactivated photocatalyst-regeneration was almost consistent to the one, according to BET analysis, at which tiny nano-pores blocked by adsorbed ethanol-oxidative and degraded intermediates (AEODI), were regenerated to be reopened through almost complete mineralization of AEODI. In particular, the results of XPS analysis indicated an incurrence of insignificant deactivation of photocatalysis upon 1st run of UV/photocatalytic reactor (A or C) of the previous investigation. In addition, the results of XPS analysis were consistent with the experimental results of the previous investigation in that 1) deactivation of photocatalyst incurred during 2nd run of the UV/photocatalytic reactor (A or C) resulted in decreased removal efficiency, by ca. 5% and 5%, of ethanol and hydrogen sulfide, respectively, compared with its 1st run; 2) there was insignificant difference between the removal efficiencies of its 2nd run and 3rd run. Furthermore, the removal efficiencies of ethanol and hydrogen sulfide for hypothetical 4th run of photocatalytic reactor in the previous investigation, using AD3, were expected to decrease, compared with its 3rd run, by much more than those for 2nd run in the previous investigation did, compared with its 1st run.

Reduction effects of N-acetyl-L-cysteine, L-glutathione, and indole-3-acetic acid on phytotoxicity generated by methyl bromide fumigation- in a model plant Arabidopsis thaliana (모델식물 애기장대에 대한 훈증제 메틸브로마이드의 약해발생 및 N-acetyl-L-cysteine, L-glutathione, indole-3-acetic acid의 약해억제 효과)

  • Kim, Kyeongnam;Kim, Chaeeun;Park, Jungeun;Yoo, Jinsung;Kim, Woosung;Jeon, Hwang-Ju;Kim, Jun-Ran;Lee, Sung-Eun
    • Korean Journal of Environmental Biology
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    • v.39 no.3
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    • pp.354-361
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    • 2021
  • Understanding the phytotoxic mechanism of methyl bromide (MB), an essential fumigant during the quarantine and pre-shipment process, is urgently needed to ensure its proper use and reduce international economic losses. In a previous study, two main MB-induced toxic mechanisms such as reactive oxygen species (ROS) and auxin distribution were selected by analyzing transcriptomic analysis. In the study, a 3-week-old A. thaliana was supplied with 1 mM ROS scavengers [N-acetyl-L-cysteine (NAC) or L-glutathione (GSH)] and 1µM indole-3-acetic acid(IAA) three times every 12 h, and visual and gene expression assessments were performed to evaluate the reduction in phytotoxicity by supplements. Phytotoxic effects on the MB-4h exposed group were decreased with GSH application compared to the other single supplements and a combination of supplements at 7 days post fumigation. Among these supplements, GSH at a concentration of 1, 2, and 5mM was suppled to A. thaliana with MB-fumigation. During a long-term observation of 2 weeks after the fumigation, 5 mM GSH application was the most effective in minimizing MB-induced phytotoxic effects with up-regulation of HSP70 expression and increase in main stem length. These results indicated that ROS was a main key factor of MB-induced phytotoxicity and that GSH can be used as a supplement to reduce the phytotoxicity of MB.

Increased Anti-oxidative Activity and Whitening Effects of a Saposhnikovia Extract Following Bioconversion Fermentation using Lactobacillus plantarum BHN-LAB 33 (Lactobacillus plantarum BHN-LAB 33의 생물전환공정을 통한 방풍 발효 추출물의 항산화 활성 및 미백 활성 증대 효과)

  • Kim, Byung-Hyuk;Jang, Jong-Ok;Lee, Jun-Hyeong;Park, YeEun;Kim, Jung-Gyu;Yoon, Yeo-Cho;Jeong, Su Jin;Kwon, Gi-Seok;Lee, Jung-Bok
    • Journal of Life Science
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    • v.29 no.11
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    • pp.1208-1217
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    • 2019
  • Saposhnikovia has been used as a traditional medicinal herb in Asia because of the reported anti-inflammatory, anti-allergic rhinitis, pro-whitening, anti-atopy, anti-allergy, and anti-dermatopathy effects of the phytochemical compounds it contains. In this study, we investigated the antioxidant effects of a Saposhnikovia extract after fermentation by Lactobacillus plantarum BHN-LAB 33. Saposhnikovia powder was inoculated with L. plantarum BHN-LAB 33 and fermented at $37^{\circ}C$ for 72 hr. After fermentation, the total polyphenol content of the Saposhnikovia extract increased by about 14%, and the total flavonoid content increased by about 9%. The superoxide dismutase-like activities, DPPH radical scavenging, ABTS radical scavenging, reducing power activity, and tyrosinase inhibition activity also increased after fermentation by approximately 70%, 80%, 45%, 39%, and 44%, respectively. The results confirmed that fermentation of a Saposhnikovia extract by L. plantarum BHN-LAB 33 is an effective way to increase the antioxidant effects of the extract. The bioconversion process investigated in this study may have the potential to produce phytochemical-enriched natural antioxidant agents with high added value from Saposhnikovia matrices. These results can also be applied to the development of improved foods and cosmetic materials.

Association Between Suicide and Diet (자살과 식단의 연관성)

  • Eunji, Lim;Bong-Jo, Kim;Cheol-Soon, Lee;Boseok, Cha;So-Jin, Lee;Jae-Won, Choi;Young-Ji, Lee;Nuree, Kang;Dongyun, Lee
    • Korean Journal of Psychosomatic Medicine
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    • v.30 no.2
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    • pp.73-79
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    • 2022
  • Objectives : Suicide is a global social problem. Social burden caused by suicide is gradually increasing. Various efforts have been made to prevent suicide. Lifestyle changes to western style, especially diet changes, have increased the risk for suicide. Therefore, in this study, we discussed diet as an adjuvant treatment for suicide. Methods : In this review, we summarized the biochemical mechanism of suicide, and diet as a risk factor for suicide and diet as a protective factor through a web search. Results : In this study, biochemical mechanisms for suicide were reviewed and diet as a risk factor and diet as a protective factor for suicide were investigated. It was confirmed that neurotoxic effects such as oxidative stress and inflammation in the neural system could increase the risk of suicide. Based on results of previous studies on the relationship between suicide and diet, it was found that heavy use of alcohol, coffee, carbonated soft drink, and fast food were risk factors for suicide. Protective factors for suicide included antioxidants such as vitamin C, carotene, and anti-inflammatory agents such as omega-3 fatty acids found in seafood in large amounts. Conclusions : The only treatment for suicide is prevention. In this context, effectiveness, accessibility, and safety are important for preventing for suicide. Antioxidants and anti-inflammatory agents that are relatively safe and readily available to the public could be effective adjuvant treatments to decrease the risk of suicide. In addition, it is necessary to educate the public on reducing diets that could increase the risk of suicide

Leaching Behavior of Vanadium and Possibility of Recovery of Valuable Metals from VTM Concentrate by Sulfuric Acid Leaching (바나듐함유 티탄철석 정광으로부터 황산 침출법에 의한 바나듐의 침출거동 및 유가금속의 회수가능성)

  • Joo, Sung-Ho;Shin, Dong Ju;Lee, Dongseok;Park, Jin-Tae;Jeon, Hoseok;Shin, Shun Myung
    • Resources Recycling
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    • v.31 no.1
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    • pp.65-77
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    • 2022
  • A study was conducted in Korea on the leaching behavior and possibility of recovery of vanadium and other valuable metals from domestic vanadium titanomagnetite (VTM) by direct acid leaching. In this study, a VTM concentrate containing 0.8% V2O5 was used, and the ratio of magnetite to ilmenite was calculated as 1.9:1 by using the HSC program. The leaching behavior of vanadium from the VTM was similar to that of iron, and it was affected by the concentration of sulfuric acid and temperature. Further, titanium could be leached in the form of TiOSO4 at a temperature higher than 75℃. To improve the leaching efficiency of V, Fe, and Ti in VTM, reductive sulfuric acid and oxidative sulfuric acid leaching were performed. When Na2SO3 was used as a reducing agent, the leaching rate of vanadium was 80% of that in that case of leaching by sulfuric acid. Similarly, the leaching rate of titanium increased from 20% to 50%. When Na2S2O8 was used as an oxidation agent, most of the vanadium was leached, and the main residue found by XRD analysis was ilmenite. In studies on the possibility of recovering valuable metals, the selective extraction of metals is hardly achieved by solvent extraction from oxidation leaching solutions; however, in this study, Cyanex 923, a solvation extractant from reductive leaching solutions, could selectively extract Ti.