• Journal of Environmental Health Sciences
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• v.19 no.4
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• pp.59-66
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• 1993

The cellular toxicity and antitumor effects of bleomycin are thought to be occurred by formation of O$_2$-Fe$^{2+}$-bleomycin complexes that degrade DNA and release O$_2^-$ and $^{\cdot}$OH radicals. Hydroxyl radicals derived from hydrogen peroxide seem most likely to be involved in the various stages of carcinogenesis, and transition metals such as iron play a central role in activation of bleomycin and in formation of hydroxyl radicals. This study was performed to investigate whether treatment with ferrous sulfate increase chromosome aberration induced by bleomycin and hydrogen peroxide, and whether there is different repair mechanism for DNA damage induced by those chemicals. Treatment with 3AB, Ara C, during G$_1$ and post-treatment with caffeine, and Hu during G$_2$ increased the frequency of chromosome aberration induced by bleomycin but post-treatment with caffeine only did function that way when hydrogen peroxide was treated. When 6.6X 10$^{-7}$ M of bleomycin or 5.0X10$^{-5}$M of hydrogen peroxide were treated simultaneously with iron, the frequency of chromosome aberration was reduced, if compared with the results by bleomycin or hydrogen per oxide alone.

• The Journal of Korean Medicine
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• v.32 no.1
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• pp.141-150
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• 2011

Objectives: The aim of this study was to elucidate the antioxidant effect of solvent fractions of Angelica gigas root. Methods: The ethanol extract of Angelica gigas root was suspended in water and then partitioned with dichloromethane (MC Fr.), ethyl acetate (EA Fr.) and butanol (BuOH Fr.), sequentially. The antioxidant activities of solvent fractions of Angelica gigas root were evaluated for radical scavenging activity against stable free radicals (2,2-diphenyl-1-picrylhydrazyl) DPPH, hydrogen peroxide and superoxide anion radicals. In addition the antioxidant activities of solvent fractions of Angelica gigas root against peroxyl radicals, hydroxyl radicals and peroxynitrites were determined by the total oxy-radical scavenging capacity (TOSC) assay. Results: Among the solvent fractions of MC Fr., EA Fr., and BuOH Fr., BuOH Fr. was found to have stronger antioxidant activity with $IC_{50}$ values of 59.72, 14.36, 30.96 and $44.75\;{\mu}g/m{\ell}$ on the DPPH radical, nitrite, superoxide anion and hydrogen peroxide, respectively, than BHA used as a positive control. Moreover, specific TOSC values(564.8, 276.4 and 405.5 TOSC/mM) of BuOH fr. against peroxyl radicals, hydroxyl radical and peroxynitrite were 4 times higher than GSH (136.5, 67.4 102.6 TOSC/mM) used as a positive control. Conclusions: These results suggest that the BuOH fr. of Angelica gigas root has a high antioxidant activity and can be useful to develop functional food against oxidative stress conditions.

• Journal of Oriental Neuropsychiatry
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• v.17 no.1
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• pp.1-16
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• 2006

Objective: An water extract of the Hwang-Ryun-Chung-Sim-Um (HRC) was assessed to determine the mechanisms of its antioxidant activity. In addition, the HRC was examined in vitro for the inhibitory effect on the acetylcholinesterse (AChE). Methods: The HRC exhibited a concentration-treatment; scavenging ${\alpha},{\alpha}-diphenyl-{\beta}-picrylhydrazyl$ (DPPH) radical, linoleic acid oxidation in a thiocyanate assay system, hydroxyl radical-induced DNA nicking. We investigated mRNA levels such as catalase activity, superoxide-dismutase and glutathione peroxidase. The water extract of HRC showed inhibitory effect on AChE activity. Result: The HRC extract showed dose-dependent free radical scavenging activity, including DPPH radicals and hydroxyl radicals, using different system. The HRC was also found to be effective in protecting plasmid DNA against the strand breakage induced by Hydroxyl radicals in Fenton's reaction mixture. Futhermore, catalase mRNA expression levels increased, but SOD1 and MnSOD was not expressed. HRC in a various concentration-dependent decreased AChE mRNA levels and inhibitory effect showed AChE. Conclusion: According to the above results, it is supposed that HRC is applicable to the Dementia-type of Alzheimer clinically.

• Journal of Photoscience
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• v.9 no.2
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• pp.138-141
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• 2002

A photo-labile compound which is bioinactive but, upon irradiation with light, yields bioactive species is called as "caged compound". Photolysis of caged compounds generating bioactive species, has become a general method to produce a desired amounts of bioactive species in the specific time interval at the desired place or area of the target biological systems. For this purpose, we designed and synthesized caged hydroxyl radical., "Photo-Fenton Reagent" NP-IIl. NP-IIl has a strong absorption maximum at 377 nm and yields hydroxyl radicals upon UV light irradiation. The antioxidant activity of the ${\alpha}$ -lipoic acid and other naturally occurring compounds has been examined by using NP-IIl as a molecular probe. For example, upon photoirradiation of NP-lII with BSA or apolipoprotein of human low density (LDL), the significant oxidative modifications were observed in both cases. The oxidation was completely suppressed in the presence of ${\alpha}$-lipoic acid, which clearly demonstrates the strong hydroxyl radical scavenging activity of ${\alpha}$-lipoic acid. Other applications of NP-lII will also be described

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.45-48
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• 1990

Maltol(2-methyl-3-hydroxy-r-pyrone), a component known to be present in Korean Ginseng root showed an antioxidant action but its potency as an antioxidant was low; about 1150th that of other antioxidants such as p-phenylenediamine , BHA and BHT. However, maltol was able to protect the oxidation adamants in biological systems such as adriamycin-induced membrane damage in isolated cardiomyocytes, parquet-induced toxicities in isolated hepatocytes and repercussion injury in isolated hearts. The antioxidant action of maltol was also shown to be effective in vivo. The antioxidant action of this compound was probably due to the removal of hydroxyl radicals. In view of the roles of oxygen radical in various pathological processes, Korean Ginseng root, which contains several antioxidants including maltol, is expected to have beneficial efforts on the oxygen radical-involved processes. Keywords Maltol, Oxygen free radicals, Lipid preoccupation, Repercussion injury and Korean ginseng

• Food Science and Biotechnology
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• v.16 no.1
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• pp.71-77
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• 2007

The antioxidant properties of twelve phenolic compounds, including matairesinol 4'-O-$\beta$-D-glucoside, 8'-hydroxyarctigenin 4'-O-$\beta$-D-glucoside, matairesinol, 8'-hydroxyarctigenin, N-feruloylserotonin 5-O-$\beta$-D-glucoside, N-(p-coumaroyl)-serotonin-5-O-$\beta$-D-glucoside, N-feruloylserotonin, N-(p-coumaroyl)serotonin, luteolin 7-O-$\beta$-D-glucoside, luteolin, acacetin 7-O-$\beta$-glucuronide, and acacetin, isolated from defatted safflower (Carthamus tinctorius L.) seeds were evaluated with regard to the DPPH, superoxide and hydroxyl radicals. Additionally, levels of phenolic compounds were determined by HPLC in two cultivars of safflower seeds. Among them, four serotonin derivatives showed potent DPPH ($IC_{50}=10.83-21.75\;{\mu}M$) and hydroxyl ($IC_{50}=75.93-374.63\;{\mu}M$) radical scavenging activities, and their activities were significantly stronger than that of ${\alpha}-tocopherol$. Four flavonoids ($IC_{50}=170.65-275.83\;{\mu}M$) and four lignans ($IC_{50}=114.22-406.10\;{\mu}M$) exhibited significant superoxide and hydroxyl radical scavenging activities, respectively, whereas these compounds contained less activity toward the DPPH and hydroxyl radicals than serotonin derivatives. The levels of serotonin derivatives, lignans and flavonoids in safflower seeds of two cultivars ranged from 49.30 to 260.40, 3.72 to 158.90, and 11.72 to 214.97 mg% (dry base), respectively. Of the two cultivars, 'Cheongsu' had somewthat higher concentrations of phenolic compounds than 'Uisan'. These results suggest that phenolic compounds in safflower seeds may playa role as protective phytochemical antioxidants against reactive oxygen-mediated pathological diseases.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.90-98
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• 2007

The antioxidant activities of water ($H_2O$) and ethanol (EtOH) extracts from hamcho (Salicornia herbacea L.) juice and cake prepared by enzymatic treatments were evaluated by in vitro assays against DPPH, superoxide, and hydroxyl radicals. Among the $H_2O$ and EtOH extracts from five different carbohydrases treated, the EtOH extract from viscozyme-treated hamcho cake had higher yield and phenolic content, and exhibited the strongest radical scavenging activity against DPPH ($IC_{50}=186.91\;{\mu}g/mL$), superoxide ($IC_{50}=87.54\;{\mu}g/mL$), and hydroxyl radicals ($IC_{50}=367.07\;{\mu}g/mL$). Antioxidant assay-guided fractionation and purification of the EtOH extract led to isolation and identification of five phenolic compounds, procatechuic, ferulic and caffeic acids, quercetin, and isorhamnetin. Most of these phenolic compounds exhibited considerable DPPH, superoxide, and hydroxyl radical scavenging activities, and in particular, caffeic and ferulic acids had stronger superoxide and hydroxyl radical scavenging activities than the well-known antioxidant radical scavenger, (+)-catechin (p<0.05). Quercetin and isorhamnetin were the primary compounds responsible for the strong antioxidant activity in the EtOH extract of the viscozyme-treated hamcho cake. Meanwhile, these five phenolic compounds were detected in the EtOH extract of the viscozyme-treated hamcho cake at the following levels (dry base of hamcho); procatechuic acid (1.54 mg%), caffeic acid (6.87 mg%), ferulic acid (8.45 mg%), quercetin (12.63 mg%), and isorhamnetin (6.65 mg%). However, three of these phenolic compounds (procatechuic, caffeic acid, and ferulic acids) were detectable in the $H_2O$ extract of viscozyme-treated hamcho juice. These results suggest that the EtOH extract of viscozyme-treated hamcho cake may be a potential source of natural antioxidants.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.266-278
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• 2008

Erythrina stricta, a deciduous tree widely used traditionally in indigenous system of medicine for various ailments such as rheumatism, fever, leprosy, epilepsy etc. The leaves of Erythrina stricta was extracted with ethanol (70%) and used for the evaluation of various in vitro antioxidant assays which includes H - donor activity, nitric oxide scavenging, superoxide anion scavenging, reducing ability, hydroxyl radical, hydrogen peroxide scavenging, total phenolic content, total flavonoid content, total antioxidant activity by thiocyanate and phosphomolybdenum method, metal chelating, $\beta$-carotene bleaching, total peroxy radical assays. The pro-oxidant activity was measured using bleomycin-dependent DNA damage. Ex vivo models like lipid peroxidation and erythrocyte haemolysis were also used to study the antioxidant property of the extract. The various antioxidant activities were compared with suitable standard antioxidants such as ascorbic acid, butylated hydroxyl toluene, $\alpha$-tocopherol, curcumin, quercetin and Trolox. The generation of free radicals viz. $O_2^{{\cdot}-}$, $OH^{\cdot}$, $H_2O_2$, $NO^{\cdot}$ and peroxyl radicals were effectively scavenged by the ethanolic extract of Erythrina stricta. In all the methods, the extract offered strong antioxidant activity in a concentration dependent manner. The total phenolic content, flavonoid content and total antioxidant activity in Erythrina stricta were determined as microgram (g) pyrocatechol, quercetin and $\alpha$-tocopherol equivalent/mg respectively. The extract did not exhibit any prooxidant activity when compared with ascorbic acid. The results obtained in the present study clearly indicates that Erythrina stricta scavenges free radicals and reduces lipid peroxidation, ameliorating the damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.393-397
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• 2007

The sonolytic decomposition of NHCs(Nitrogen Heterocyclic Compounds), such as atrazine[6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine], simazine(6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N'-triethyl-1,3, 5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range $1.06{\sim}2.07({\times}10^{-2}min^{-1})$ under air and $1.30{\sim}2.59({\times}10^{-2}min^{-1})$ under argon at a concentration of $200{\mu}M$ of NHCs. The rate of hydroxyl radicals(${\bullet}{OH}$) formation from water is $19.8{\mu}M\;min^{-1}$ under argon and $14.7{\mu}M\;min^{-1}$ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ${\bullet}{OH}$ radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ${\bullet}{OH}$ radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent $[Fe^{2+}]$ accelerates the decomposition. This is probably due to the regeneration of ${\bullet}{OH}$ radicals from hydrogen peroxide, which would be formed from recombination of ${\bullet}{OH}$ radicals and which may contribute a little to the decomposition.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.171-176
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• 2003

The sonolytic decomposition of NHCs, such as atrazine［6-chloro-N-ethyl-N＇ -(1-methylethyl)-1,3,5-triazine-2,4-diamine］, simazine( 6-chloro-N,N＇ -diethyl-l ,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N＇-triethyl-l,3,5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range 1.06∼2.07 (x10/sup -3/ min/sup -1/) under air and 1.30∼2.59(x10/sup -3/ min/sup -1/)under argon at a concentration of 200μM of NHCs. The rate of hydroxyl radicals(·OH) formation from water is 19.8μM min/sup -1/ under argon and 14.7 μM min/sup -1/ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ·OH radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ·OH radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent ［Fe/sup 2＋/］ accelerates the decomposition. This is probably due to the regeneration of ·OH radicals from hydrogen peroxide, which would be formed from recombination of ·OH radicals and which may contribute a little to the decomposition.