• 제목/요약/키워드: Cation radical

Search Result 220, Processing Time 0.02 seconds

Neuroprotective Effects of Bunsimgieum (분심기음(分心氣飮)의 도파민 세포 보호 효과)

  • Kim, Ro-Sa;Lee, Chang-Hoon;Lee, Jin-Moo;Cho, Jung-Hoon;Jang, Jun-Bock;Lee, Kyung-Sub
    • The Journal of Korean Obstetrics and Gynecology
    • /
    • v.22 no.2
    • /
    • pp.119-131
    • /
    • 2009
  • Purpose: The depression accompanied with menopuase shows the relation with the dopamine secretion. These studies were undertaken to evaluate the anti- oxidative and neuroprotective effects of Bunsimgieum(BSGE) on dopaminergic neurons. Methods: To estimate the antioxidant effects, we carried out 1.1-diphenyl-2- picrylhydrazyl (DPPH) free radical scavenging assay, 2,2'-azinobis-(3-ethylbenzothiazoline -6-sulfonic acid (ABTS) radical cation decolorization assay, and measurement of total polyphenolic content. To evaluate neuroprotective effect of BSGE in vitro, We performed thiazolyl blue tetrazolium bromide (MTT) assay, reactive oxygen species (ROS) creation in SH-SY5Y. Tyrosine hydroxylase (TH) immunocytochemistry, nitric oxide (NO) assay, and TNF-${\alpha}$ assay in primary rat mesencephalic dopaminergic neurons. Results: The DPPH free radical and the ABTS radical cation inhibition activities were increased at a dose dependent manner. Total polyphenolic content was 0.83%. In SH-SY5Y culture, BSGE significantly increased the decreased cell viability by 6-OHDA at the concentrations of 10${\mu}$g/m${\ell}$ in pre-treatment group, 0.1-200${\mu}$g/m${\ell}$ in post-treatment group. The production of ROS induced by 6-OHDA was significantly inhibited in BSGE treated group. In mesencephalic dopaminergic cell culture, the BSGE group reduced the dopaminergic cell loss against 6-OHDA toxicity and the production of No and TNF-${\alpha}$ at the concentration of 5${\mu}$g/m${\ell}$. Conclusion: These results shows that BSGE has antioxidant and neuroprotective effects in the dopaminergic cells through decreasing the production of ROS, NO and TNF-${\alpha}$ which can cause many neurodegenerative changes in brain cell. We suggest that BSGE could be useful for the treatment of postmenopausal depression related with the decrease of dopamine.

Neuroprotective and Free Radical Scavenging Activities of Phenolic Compounds from Hovenia dulcis

  • Li, Gao;Min, Byung-Sun;Zheng, Chang-Ji;Lee, Joong-Ku;Oh, Sei-Ryang;Ahn, Kyung-Seop;Lee, Hyeong-Kyu
    • Archives of Pharmacal Research
    • /
    • v.28 no.7
    • /
    • pp.804-809
    • /
    • 2005
  • The EtOAc-soluble fraction from a methanolic extract of Hovenia dulcis Thunb. exhibited neuroprotective activity against glutamate-induced neurotoxicity in mouse hippocampal HT22 cells. The neuroprotective activity-guided isolation resulted in 8 phenolic compounds (1-8), such as vanillic acid (1), ferulic acid (2), 3,5-dihydroxystilbene (3), (+)-aromadendrin (4), methyl vanillate (5), (-)-catechin (6), 2,3,4-trihydrobenzoic acid (7), and (+)-afzelechin (8). Among these, compounds 6 and 8 had a neuroprotective effect on the glutamate-induced neurotoxicity in HT22 cells. Furthermore, compound 6 had a DPPH free radical scavenging effect with an $IC_{50}$ value of $57.7{\mu}M$, and a superoxide anion radical scavenging effect with an $IC_{50}$ value of $8.0{\mu}M$. Both compounds 6 and 8 had ABTS cation radical scavenging effects with $IC_{50}$ values of $7.8{\mu}M\;and\;23.7${\mu}M$, respectively. These results suggest that compounds 6 and 8 could be neuroprotectants owing to their free radical scavenging activities.

Electrochemical Properties of Diiron Complexes wish Conjugated Chains (공액 사슬을 갖는 철 화합물의 전기화학적 특성)

  • ;Micheal b. Sponsler
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.15 no.6
    • /
    • pp.511-517
    • /
    • 2002
  • The complex 1 $([Cp*Fe(CO)_2]_2-(\mu-CH=CH-CH=CH))$ which have butadiene as a bridge were synthesized from $Cp*(CO)_2FeK$ and cis-3,4-dichlorocyclobutene. The derivatives of complex 1 where one or two carbonyl groups are replaced by phosphine ligands have been prepared by photochemical substitution. The new derivatives $([Cp*Fe(L)_2]_2-(\mu-CH=CH-CH=CH))$ where L = $(Ph_2PCH_2CH_2PPh_2)$ and $([Cp*Fe(CO)(L)]_2-(\mu-CH=CH-CH=CH))$ where L : $PPh_3$ have been characterized from $^^1H-$, $^^13C-$,$^^31P-NMR$ and elemental analysis. Obtained complexes have been studied in electrochemical experiment and UV/VIS-near-IR. The mixed-valence radical cation forms of complex 2, 3 species were found to be delocalized as the Class III. Based on the separation of the waves ($\triangle E$ : 0.470 ~ 0.605 V), the efficiency of electronic communication between two metal centers of cation species leading to stabilization relative to neutral species. The phosphine-substitute complexes (2, 3) displays two reversible oxidation waves and oxidation state of metal centers-dependent color change, electrochromism, was observed from yellow to orange and deep blue in methylene chloride.

Recent Advances in Di-$\pi$-methane Processes. Novel Reactions of 1,4-Unsaturated Compounds Promoted by Triplet Sensitization and Photoelectron Transfer

  • Armesto, Diego;Ortiz, Maria J.;Agarrabeitia, Antonia R.
    • Journal of Photoscience
    • /
    • v.10 no.1
    • /
    • pp.9-20
    • /
    • 2003
  • Recent studies on the photoreactivity of l,4-unsaturated systems have changed some ideas that were firmly established in this area of research for many years. Thus, we have described the first examples of 2-aza-di-$\pi$-methane (2-ADPM) rearrangements promoted by triplet-sensitization and by single electron transfer (SET) using electron-acceptor sensitizers. These reactions afford N-vinylaziridine and cyclopropylimine photoproducts in the first examples of di-$\pi$-methane processes that yield three-membered ring heterocycles. l-Aza-1,4-dienes also undergo SET-promoted l-aza-di-$\pi$-methane (l-ADPM) rearrangements via radical-cation intermediates using electron acceptor sensitizers. In some cases, alternative cyclizations yielding different carbocycles and heterocycles have been observed. The l-ADPM and di-$\pi$-methane (DPM) reactions also occur via radical-anion intermediates on irradiation using electron donor sensitizers. On the other hand, the photoreactivity reported for $\beta$,${\gamma}$-unsaturated aldehydes for many years was decarbonylation to the corresponding alkenes. However, our studies demonstrate that these compounds undergo the oxa-di-$\pi$-methane (ODPM) rearrangement with high chemical and quantum efficiency. A comparison of the photochemical reactivity of $\beta$,${\gamma}$-unsaturated aldehydes and corresponding methyl ketones has shown that the ketones do not undergo the ODPM rearrangement while the corresponding aldehydes are reactive by this pathway. Monosubstituted $\beta$,${\gamma}$-unsaturated aldehydes at C-2 undergo the ODPM rearrangement yielding the corresponding cyclopropane carbaldehydes diastereoselectively. Finally, we have described the first examples of reactions, similar to the well know Norrish Type I process, which take place in the triplet excited state of $\beta$,${\gamma}$-unsaturated carbonyl compounds by excitation of the C-C double bond instead of the carbonyl group.

  • PDF

Antioxidant and Anticholinesterase Potential of Two Nigerian Bitter Yams Using a Simulated Gastrointestinal Digestion Model and Conventional Extraction

  • Salawu, Sule Ola;Ajiboye, Praise Blessing;Akindahunsi, Akintunde Afolabi;Boligon, Aline Augusti
    • Preventive Nutrition and Food Science
    • /
    • v.22 no.2
    • /
    • pp.107-117
    • /
    • 2017
  • The purpose of this study was to evaluate the antioxidant and anticholinesterase activities of yellow and white bitter yams from South Western Nigeria using methanolic extraction and simulated gastrointestinal digestion models. The phenolic compounds in the bitter yam varieties were evaluated by high performance liquid chromatography with a diode array detector (HPLC-DAD). The total phenolic content of the bitter yams was measured by the Folin-Ciocalteu method, reductive potential by assessing the ability of the bitter yam to reduce $FeCl_3$ solution, and the antioxidant activities were determined by the 2,2-diphenyl-1-picrylhydrazyl radical ($DPPH^{\cdot}$) scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation ($ABTS^{{\cdot}+}$) scavenging activity, nitric oxide radical ($NO^{\cdot}$) scavenging ability, hydroxyl radical scavenging ability, and ability to inhibit $Fe^{2+}$-induced lipid oxidation. The HPLC-DAD analysis revealed the presence of some phenolic compounds in the studied bitter yam varieties, with varying degree of quantitative changes after cooking. The antioxidant indices (total phenolic content, total flavonoid content, reducing power, $DPPH^{\cdot}$ scavenging activity, $ABTS^{{\cdot}+}$ scavenging activity, and $NO^{\cdot}$ scavenging activity) were higher in the simulated gastrointestinal digestion model compared to the methanolic extract, with the in vitro digested cooked white bitter yam ranking higher. Similarly, the in vitro digested yams had a higher inhibitory action against lipid oxidation compared to the methanolic extracts, with the cooked white bitter yam ranking high. The methanolic extracts and in vitro enzyme digests showed no acetylcholinesterase inhibitory abilities, while methanolic extracts and the in vitro enzyme digest displayed some level of butyrylcholinesterase inhibitory activities. Therefore the studied bitter yams could be considered as possible health supplements.

Screening of Biological Activity of Caragana sinica Extracts (골담초(Caragana sinica) 추출물의 생리활성 탐색)

  • Jeon, Young-Suk;Jo, Bun-Sung;Park, Hye-Jin;Kang, Sun-Ae;Cho, Young-Je
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.41 no.9
    • /
    • pp.1211-1219
    • /
    • 2012
  • In this study, extracts from Caragana sinica flowers and leaves were tested for antioxidant and angiotensin converting enzyme inhibitory activities, along with xanthine oxidase, tyrosinase, elastase, and astringent effects. Total phenolic compounds of acetone extracts from Caragana sinica flowers and leaves were the highest at 3.42 and 2.98 mg/g, respectively, when various extraction solvents were used. Optimal conditions for extraction of phenolic compounds from Caragana sinica leaves and flowers were 70% ethanol for 18 hr. DPPH scavenging activities were the highest in 70% ethanol extracts of Caragana sinica. ABTS radical cation decolorization values of 70% ethanol extracts were higher than those 60% ethanol extracts at 74%. Antioxidant protection factor was 1.2 PF in 70% ethanol extracts from Caragana sinica flowers and leaves. TBARS was lower than that of control (0.54 ${\mu}M$) in all sections. Angiotensin converting enzyme inhibitory activity of Caragana sinica flower extract was 80~90% at a phenolic concentration of 0.2~1.0 mg/mL, whereas xanthin oxidase inhibitory activity of Caragana sinica leaf extract was higher than that of flower extract. Tyrosinase inhibitory activity, which is related to skin-whitening, was above 20%, whereas elastase inhibitory activity related to anti-wrinkle effect was above 50% at a phenolic concentration of 0.8 mg/mL. Astringent effects of Caragana sinica flower and leaf extracts were higher than tannic acid as a control at an equivalent concentration. This result suggests that extracts from Caragana sinica flowers and leaves are suitable as functional foods having anti-hypertension, anti-gout, and medicinal cosmetic activities, including whitening and anti-wrinkle effects.

Antioxidant Activities of Various Solvent Extracts from Ginseng (Panax ginseng C.A. Meyer) Leaves

  • Kang, Ok-Ju
    • Preventive Nutrition and Food Science
    • /
    • v.16 no.4
    • /
    • pp.321-327
    • /
    • 2011
  • Water, methanol and ethanol extracts of ginseng leaves were assayed for total phenolics and flavonoids, ascorbic acid, cupric and ferrous ion chelating activities, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP) assay and ABTS radical cation decolourization (TEAC) assay for their antioxidant properties. The ethanol extract of ginseng leaves contained significantly (p<0.05) higher amounts of total phenolics and flavonoids (600.57 and 1701 mg/100 g) than methanol (374.43 and 1512.64 mg/100 g) and water extracts (248.30 and 680.05 mg/100 g). Among solvent extracts of ginseng leaves, the ethanol extract showed the most powerful antioxidant activities. However, the ferrous ion chelating activity of ginseng leaf extracts were lower than the cupric ion chelating ability. These differences in concentrations of key antioxidants among various solvent extracts seemed to be responsible for their differences in antioxidant activities. These results suggest that ethanol extract of ginseng leaves has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus, it can be applied for the effective extraction of functional material from ginseng leaves for the usage of pharmaceutical and/or food industries.

Potential of proteolytic enzyme treatment for production of Korean red ginseng extract (홍삼 추출물의 제조에서 단백질 분해효소의 활용)

  • Kim, Dong Chung;Lee, Tae Jung;In, Man-Jin
    • Journal of Applied Biological Chemistry
    • /
    • v.62 no.4
    • /
    • pp.385-389
    • /
    • 2019
  • In this study, proteolytic enzymatic treatment conditions for Korean red ginseng were examined to increase the extraction yield. Commercially available proteases were screened to obtain high protein and carbohydrate yield. The optimal dosage and reaction time for Alcalase, the chosen protease, were found to be 2.0% (w/w) and 1.5 h, respectively. Treatment with optimal conditions of Alcalase increased solid yield, total phenolic content and gensenosides content by 57.6, 81.8, and 33.8%, respectively, over levels in non-treated Korean red ginseng. Antioxidative activities evaluated by free radical scavenging activity, cation radical scavenging activity and reducing power were exactly similar between Alcalase-treated and non-treated extracts.

Electrochemical Study of Functional Organic Monomolecular Film prepared by Langmuir-Blodgett Method (기능성 유기 LB단분자막의 전기화학적 연구)

  • 박수길;임기조;전일철;이주성
    • Journal of the Korean institute of surface engineering
    • /
    • v.28 no.1
    • /
    • pp.34-45
    • /
    • 1995
  • An amphiphilic nitroxide radical(2,2'6,6'-tetramethyl-4-octadecyioxy-1-piperidinyloxyl, TEMOPO) or mixture of TEMOPO and arachidic acid(Icosanoic acid, AA), was spread on water surface by the Langmuir-Blodgett(LB) method and surface pressure-area curve was measured. Such monolayer films of TEMOPO were transferred onto surfaces of photo transferable tin oxide electrodes(PTTO) by the LB method under various surface pressure with the transfer ratio of larger than 0.95 at the surface pressure higher than 15mN/m. The electrochemical effect of functional nitroxy radical monolayer onto semi-conductive electrode to electrolyte have been investigated by using LB method. Cyclic voltammetry technique was used for the electrochemical behavior measurement of TEMOPO monolayer onto the PTTO in 0.18 mo1/$dm^3$ $H_2SO_4$ solutions. The shape of voltammograms was found to change from one electrode to another. The amount of charge for the oxidation and the re-reduction of the cation to TEMOPO were evaluated from graphical integration. The amounts of charge were always smaller than those predicted from the $\pi$-$\sigma$ curves though the transfer ratio was unity. The poor reproducibility of the cyclic voltammograms was improved by the mixing with AA. Structure and arrangement of monomolecular layer on water surface and electrode were studied. Characteristics of monolayer film applied for the mediation reaction was also discussed by electrochemical method.

  • PDF

Analysis of Papers on Curcuma longa Rhizoma for Possibility Evaluation of Therapeutic against dementia (강황의 항치매효과에 대한 체계적인 문헌고찰)

  • Jo, Na Young
    • The Journal of the Society of Korean Medicine Diagnostics
    • /
    • v.22 no.1
    • /
    • pp.11-18
    • /
    • 2018
  • Objectives The incidence of degenerative diseases is increasing as society ages, and this increased the economic burden on society. Oxidative stress was also under suspicion as one of the causes. Recent studies have found that Curcuma longa Rhizoma had antioxidant, anti-inflammatory, antimutagenic, and anticancer effects. Through this study, we figure out trends in Curcuma longa Rhizoma research and evaluate the therapeutic potential of Curcuma longa Rhizoma for dementia. Methods The search was made using domestic and international internet search sites. "Naver academic," "Google scholar," "Korea institute of oriental medicine (KIOM OASIS)," "Korean traditional knowledge portal (KTKP)," "Library of Congress," "Research information sharing service (RISS)," "National Digital Science Links (NDSL)," and "Pub med" are used to search. The searched for words were "turmeric," "Curcuma longa Rhizoma," "antioxidant," and "nerve regeneration." Results It could be seen that a lot of research done on Curcuma longa recently. In previous studies, the most common research disease was cancer. In previous studies, the most common effects of Curcuma longa was antioxidant and anticancer. Curcumin, Vitamin B1, and various essential oils were the functional components of Curcuma longa Rhizoma. Curcuma longa Rhizoma performs DPPH radical scavenging activity and ABTS radical cation decolorization activity; it inhibits NO and iNOS. Conclusion The destruction of nerve cells due to oxidative stress is a cause of dementia. Curcuma longa Rhizoma have antioxidant effects. Therefore, we believed that it is an effective treatment for dementia. Various studies will be made on Curcuma longa Rhizoma.

  • PDF