Antioxidant and radical scavenging properties of curcumin

Curcumin (diferuoyl methane) is a phenolic compound and a major component of Curcuma longa L. In the present paper, we determined the antioxidant activity of curcumin by employing various in vitro antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH*) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by the Fe(3+)-Fe(2+) transformation method, superoxide anion radical scavenging by the riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe(2+)) chelating activities. Curcumin inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 microg/mL concentration (20 mM). On the other hand, butylated hydroxyanisole (BHA, 123 mM), butylated hydroxytoluene (BHT, 102 mM), alpha-tocopherol (51 mM) and trolox (90 mM) as standard antioxidants indicated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 microg/mL concentration, respectively. In addition, curcumin had an effective DPPH* scavenging, ABTS*(+) scavenging, DMPD*(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. According to the present study, curcumin can be used in the pharmacological and food industry because of these properties.     

In vitro antioxidant activity of silymarin

Silymarin, a known standardized extract obtained from seeds of Silybum marianum is widely used in treatment of several diseases of varying origin. In the present paper, we clarified the antioxidant activity of silymarin by employing various in vitro antioxidant assay such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH(.)) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by Fe3+ - Fe2+ transformation method and Cuprac assay, superoxide anion radical scavenging by riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe2+) chelating activities. Silymarin inhibited 82.7% lipid peroxidation of linoleic acid emulsion at 30 microg/mL concentration; butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol and trolox indicated inhibition of 83.3, 82.1, 68.1 and 81.3% on peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, silymarin had an effective DPPH(.) scavenging, ABTS(.)+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power by Fe3+-Fe2+ transformation, cupric ions (Cu2+) reducing ability by Cuprac method, and ferrous ions (Fe2+) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. Moreover, this study, which clarifies antioxidant mechanism of silymarin, brings new information on the antioxidant properties of silymarin. According to the present study, silymarin had effective in vitro antioxidant and radical scavenging activity. It could be used in the pharmacological and food industry because of its antioxidant properties.     

Comparison of in vitro antioxidant and antiradical activities of L-tyrosine and L-Dopa

Summary. Phenolic compounds are interesting because of their antioxidant properties. In the present study, the antioxidant properties of L-tyrosine as a monophenolic and L-Dopa as a diphenolic amino acid were investigated by using different antioxidant assays: (i) 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH^•) scavenging; (ii) 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation decolorization assay; (iii) total antioxidant activity by ferric thiocyanate method; (iv) ferric ions (Fe³⁺) reducing power; (v) superoxide anion radical (O₂ ^•−) scavenging; (vi) hydrogen peroxide (H₂O₂) scavenging, and (vii) ferrous ions (Fe²⁺) chelating activities. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. At the same concentration (20 μg/mL), L-tyrosine and L-Dopa showed 30.6 and 67.9% inhibition of lipid peroxidation of linoleic acid emulsion, respectively. On the other hand, BHA, BHT, α-tocopherol and trolox indicated inhibitions of 74.4, 71.2, 54.7 and 20.1% on the peroxidation of linoleic acid emulsion, respectively, at the above-mentioned concentration. In addition, L-tyrosine and L-Dopa had an effect on DPPH radical scavenging, ABTS radical scavenging, superoxide anion radical scavenging, H₂O₂ scavenging, total ferric ions reducing power and metal chelating on ferrous ions activities.     

Antioxidant activity of L-adrenaline: a structure-activity insight

L-adrenaline belongs to a group of the compounds known as catecholamines, which play an important role in the regulation of physiological process in living organisms. The antioxidant activity and antioxidant mechanism of L-adrenaline was clarified using various in vitro antioxidant assays including 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), N,N-dimethyl-p-phenylenediamine (DMPD(+)), and superoxide anion radicals (O(2)(-)) scavenging activity, hydrogen peroxide (H(2)O(2)), total antioxidant activity, ferric ions (Fe(3+)) and cupric ions (Cu(2+)) reducing ability, ferrous ions (Fe(2+)) chelating activity. L-adrenaline inhibited 74.2% lipid peroxidation of a linoleic acid emulsion at 30 microg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol and trolox displayed 83.3, 82.1, 68.1 and 81.3% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. BHA, BHT, alpha-tocopherol and trolox were used as reference antioxidants and radical scavenger compounds. Moreover, this study will bring an innovation for further studies related to antioxidant properties of L-adrenaline. According to present study, L-adrenaline had effective in vitro antioxidant and radical scavenging activity.     

Antioxidant and antiradical activities of L-carnitine

L-carnitine plays an important regulatory role in the mitochondrial transport of long-chain free fatty acids. In this study, the antioxidant activity of L-carnitine was investigated as in vitro. The antioxidant properties of the L-carnitine were evaluated by using different antioxidant assays such as 1, 1-diphenyl-2-picryl-hydrazyl free radical (DPPH.) scavenging, total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities. Total antioxidant activity was measured according to ferric thiocyanate method. alpha-tocopherol and trolox, a water-soluble analogue of tocopherol, were used as the reference antioxidant compounds. At the concentrations of 15, 30 and 45 microg/mL, l-carnitine showed 94.6%, 95.4% and 97.1% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. On the other hand, 45 microg/mL of standard antioxidant such as alpha-tocopherol and trolox indicated an inhibition of 88.8% and 86.2% on peroxidation of linoleic acid emulsion, respectively. In addition, L-carnitine had an effective DPPH. scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to alpha-tocopherol and trolox as references antioxidants.     

In vitro antioxidant activity of silymarin

Silymarin, a known standardized extract obtained from seeds of Silybum marianum is widely used in treatment of several diseases of varying origin. In the present paper, we clarified the antioxidant activity of silymarin by employing various in vitro antioxidant assay such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by Fe³⁺ ? Fe²⁺ transformation method and Cuprac assay, superoxide anion radical scavenging by riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe²⁺) chelating activities. Silymarin inhibited 82.7% lipid peroxidation of linoleic acid emulsion at 30 μg/mL concentration; butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox indicated inhibition of 83.3, 82.1, 68.1 and 81.3% on peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, silymarin had an effective DPPH· scavenging, ABTS^√+ scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe³⁺) reducing power by Fe³⁺ ? Fe²⁺ transformation, cupric ions (Cu²⁺) reducing ability by Cuprac method, and ferrous ions (Fe²⁺) chelating activities. Also, BHA, BHT, α-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. Moreover, this study, which clarifies antioxidant mechanism of silymarin, brings new information on the antioxidant properties of silymarin. According to the present study, silymarin had effective in vitro antioxidant and radical scavenging activity. It could be used in the pharmacological and food industry because of its antioxidant properties.     

Antioxidant activity of bisbenzylisoquinoline alkaloids from Stephania rotunda: cepharanthine and fangchinoline

In the present study, we determined the antioxidant activity of cepharanthine and fangchinoline from Stephania rotunda by performing different in vitro antioxidant assays, including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, N,N- dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging, superoxide anion (O₂^?–) radical scavenging, hydrogen peroxide scavenging, total antioxidant activity, reducing power, and ferrous ion (Fe²⁺) chelating activities. Cepharanthine and fangchinoline showed 94.6 and 93.3% inhibition on lipid peroxidation of linoleic acid emulsion at 30 μg/mL concentration, respectively. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol, and trolox indicated inhibitions of 83.3, 92.2, 72.4, and 81.3% on peroxidation of linoleic acid emulsion at the same concentration (30 μg/mL), respectively. According to the results, cepharanthine and fangchinoline have effective antioxidant and radical scavenging activity.     

Antioxidant and free radical scavenging properties of N-acetylcysteine amide (NACA) and comparison with N-acetylcysteine (NAC)

The antioxidant potential of N-acetylcysteine amide (NACA), also known as AD4, was assessed by employing different in vitro assays. These included reducing power, free radical scavenging capacities, peroxidation inhibiting activity through linoleic acid emulsion system and metal chelating capacity, as compared to NAC and three widely used antioxidants, alpha-tocopherol, ascorbic acid and butylated hydroxytoluene (BHT). Of the antioxidant properties that were investigated, NACA was shown to possess higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging ability and reducing power than NAC, at all the concentrations, whereas the scavenging ability of H(2)O(2) differed with concentration. While NACA had greater H(2)O(2) scavenging capacity at the highest concentration, NAC was better than NACA at lower concentrations. NAC and NACA had a 60% and 55% higher ability to prevent beta-carotene bleaching, respectively, as compared to control. The chelating activity of NACA was more than 50% that of the metal chelating capacity of EDTA and four and nine times that of BHT and alpha-tocopherol, respectively. When compared to NACA and NAC; alpha-tocopherol had higher DPPH scavenging abilities and BHT and alpha-tocopherol had better beta-carotene bleaching power. These findings provide evidence that the novel antioxidant, NACA, has indeed enhanced the antioxidant properties of NAC.     

Radical scavenging activities of Heracleum aquilegifolium Wight (Apiaceae) fruit oils in vitro

The fruits of Heracleum aquilegifolium Wight (Apiaceae) were collected from Western Ghats of the Indian Peninsula. The essential oils were extracted by hydrodistillation. The chemical composition of the essential oils was analysed by gas chromatography and gas chromatography-mass spectrometry (GC-MS). Beta-Pinene (22.3%), 1,8-cineole (20.3%), and beta-phellandrene (12.4%) were the main components of H. aquilegifolium fruit oils. The antioxidant properties of essential oils of H. aquilegifolium were examined by different procedures namely reducing power ability, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, nitric oxide radical scavenging activity, hydrogen peroxide scavenging activity, hydroxyl radical scavenging activity, superoxide anion scavenging activity, and metal chelating activity. The antioxidant activities were compared with those of synthetic antioxidants and standard drugs such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), ascorbic acid, alpha-tocopherol, curcumin, and quercetin. The study confirmed the possible antioxidant potential of essential oils tested with various in vitro antioxidant methods. The presence of monoterpenes in combination with other components in the oils could be responsible for the activity.     

Bioorganic synthesis, characterization and antioxidant activity of esters of natural phenolics and α-lipoic acid

Chemo-enzymatic synthesis of six esters of natural phenolics and α-lipoic acid was carried to produce novel compounds with potential bioactivity. The synthetic route was mild, simple, and efficient with satisfactory yields. The synthesized compounds were screened for antioxidant activities. The prepared derivatives exhibited very good antioxidant activities as determined by DPPH radical scavenging assay and inhibition of lipid oxidation in fish oil emulsion system. Among the prepared derivatives, three compounds exhibited radical scavenging activity similar to the reference antioxidants, BHT and alpha-tocopherol in the DPPH radical scavenging assay, where as in fish oil emulsion system, two derivatives showed activity, which was similar to the reference antioxidants.     

Antioxidant and free radical scavenging properties of N-acetylcysteine amide (NACA) and comparison with N-acetylcysteine (NAC)

The antioxidant potential of N-acetylcysteine amide (NACA), also known as AD4, was assessed by employing different in vitro assays. These included reducing power, free radical scavenging capacities, peroxidation inhibiting activity through linoleic acid emulsion system and metal chelating capacity, as compared to NAC and three widely used antioxidants, α-tocopherol, ascorbic acid and butylated hydroxytoluene (BHT). Of the antioxidant properties that were investigated, NACA was shown to possess higher 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging ability and reducing power than NAC, at all the concentrations, whereas the scavenging ability of H₂O₂ differed with concentration. While NACA had greater H₂O₂ scavenging capacity at the highest concentration, NAC was better than NACA at lower concentrations. NAC and NACA had a 60% and 55% higher ability to prevent β-carotene bleaching, respectively, as compared to control. The chelating activity of NACA was more than 50% that of the metal chelating capacity of EDTA and four and nine times that of BHT and α-tocopherol, respectively. When compared to NACA and NAC; α-tocopherol had higher DPPH scavenging abilities and BHT and α-tocopherol had better β-carotene bleaching power. These findings provide evidence that the novel antioxidant, NACA, has indeed enhanced the antioxidant properties of NAC.     

Apoptotic, antioxidant and antiradical effects of majdine and isomajdine from Vinca herbacea Waldst. and kit

In the present study, apoptotic, antioxidant and antiradical effects of majdine and isomajdine from Vinca herbacea Waldst. and Kit were studied. For testing the possible apoptotic effects of majdine and isomajdine from V. herbacea, DNA fragmentation assay was conducted on the rat brain cortical tissue homogenates, in vitro. Also their possible effects on mitochondrial activity were tested by using the same tissue samples of rats. In addition, the antioxidant activity of isomajdine and majdine was determined using various in vitro antioxidant assays, including 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS(?+)) radical scavenging and N,N-dimethyl-p-phenylenediamine (DMPD(?+)) radical scavenging, ferric ions (Fe(3+)) and cupric ions (Cu(2+)) reducing abilities and ferrous ions (Fe(2+)) chelating activity. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) were used as reference antioxidants.     

Synthesis and antioxidant activities of novel 4-Schiff base-7-benzyloxy-coumarin derivatives

4-Schiff base-7-benzyloxy-coumarins 5a(1)-5h(2) and its derivative 6 were designed and synthesized based on the 7-benzyloxy-coumarin structure as novel antioxidants. The in vitro antioxidant activities screening revealed that 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of compounds 5b(1), 5d(1), 5f(1), 5f(2), 5g(1) and 5g(2), and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate) cation (ABTS(+)) radical scavenging activities of compounds 5a(1), 5b(1), 5c(1), 5c(2), 5d(1), 5e(1), 5e(2), 5f(2), 5g(1), 5g(2) and 5h(1) were better than that of the commercial antioxidant butylated hydroxytoluene (BHT), while the superoxide anion radical scavenging activities of 5a(2) and 5g(2) were stronger than that of the commercial antioxidant butylated hydroxyanisole (BHA), and the hydroxyl radical scavenging activity of 5e(1) was much better than that of the common antioxidant ascorbic acid.     

Evaluation of antioxidant activity of <Emphasis Type="Italic">Melothria maderaspatana in vitro</Emphasis>

In this study, an aqueous extract of leaves from Melothria maderaspatana was tested for in vitro antioxidant activity. Free radical scavenging assays, such as hydroxyl radical, hydrogen peroxide, superoxide anion radical and 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azinobis-(3-ethyl-enzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power assay, were studied. The extract effectively scavenged hydroxyl radical, hydrogen peroxide and superoxide anion radicals. It also scavenged DPPH and ABTS radicals. Furthermore, it was found to have reducing power. All concentrations of leaf extract exhibited free radical scavenging and antioxidant power, and the preventive effects were in a dose-dependent manner. The antioxidant activities of the above were compared to standard antioxidants such as butylated hydroxytoluene (BHT), ascorbic acid, and α-tocopherol. The results obtained in the present study indicate that the M. maderaspatana extract could be considered a potential source of natural antioxidant.     

Synthesis and antioxidant properties of diphenylmethane derivative bromophenols including a natural product

Bromination of bis(3,4-dimethoxyphenyl)methanone (5) gave four products (6–9) with mono, di, tri, and tetra Br under different conditions. Reduction and demethylation reactions of product 9 with tetra Br were performed, consecutively and a natural product, 5,5′-methylene bis(3,4-dibrombenzene-1,2-diol) (1), was obtained with a 53% yield. Five derivatives, (13–17) (bromophenols), of 1 were also synthesised. The antioxidant and radical scavenging activities of bromophenols 1 and 13–17 were determined by employing various in vitro assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH^?), 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS^?+), N,N-dimethyl-p-phenylenediamine dihydrochloride radical cation (DMPD^?+), and superoxide anion radical (O₂^?-) scavenging, reducing ability determination by the Fe³⁺-Fe²⁺ and Cu²⁺-Cu⁺ cupric reducing antioxidant capacity (CUPRAC) transformation methods, hydrogen peroxide scavenging, and ferrous ion (Fe²⁺) chelating activities. Moreover, these activities were compared to those of synthetic standard antioxidant compounds such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol, and trolox. The results showed that the synthesised bromophenols had effective antioxidant power.     

7种广西产甜茶抗氧化活性的比较

通过清除二苯代苦味酰基(1,1-diphenyl-2-picrylhydrazyl,DPPH)法、铁离子还原测定(ferric reducing antioxidant power,FRAP)法、亚铁离子螯合(ferrous ion-chelating,FIC)法、β-胡萝卜素-亚油酸法等4种体外抗氧化活性测定方法,首次比较了3种茶科属茶叶和7种广西产甜茶水提物的抗氧化活性,同时用Folin-Ciocalteus法测定了其总多酚的含量。研究结果表明,多穗柯甜茶和藤茶的总多酚含量高于其他供试品。藤茶具有很好的清除DPPH·的能力,高于绿茶及阳性对照水溶性维生素E(Trolox)和人工合成抗氧化剂二丁基羟基甲苯(butylated hydroxytoluene,BHT)。甜叶菊茶和悬钩甜茶的金属离子螯合能力均高于绿茶。其中,黄杞和牛白藤两种植物的抗氧化活性为首次报道。由此可见,广西产甜茶均具有较高的开发利用价值,是治疗和防治慢性代谢性疾病的重要研究对象。对广西产甜茶的研究对于了解和抢救某些少数民族的历史文化具有重要意义,为别样茶的抗氧化研究奠定了基础,值得进一步探索和开发。     

Comparison of Antioxidant Activity Between Aromatic Indolinonic Nitroxides and Natural and Synthetic Antioxidants

In view of the possible employment of nitroxide compounds in various fields, it is important to know how they compare with other synthetic antioxidant compounds currently used in several industries and with naturally occurring antioxidants. To address this issue, the antioxidant activity of two aromatic indolinonic nitroxides synthesized by us was compared with both commercial phenolic antioxidants (BHT and BHA) and with natural phenolic antioxidants (α-hydroxytyrosol, tyrosol, caffeic acid, α-tocopherol). DPPH radical scavenging ability and the inhibition of both lipid and protein oxidation induced by the peroxyl-radical generator, AAPH, were evaluated. The results obtained show that overall: (i) the reduced forms of the nitroxide compounds are better scavengers of DPPH radical than butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) but less efficient than the natural compounds; (ii) the nitroxides inhibit both linolenic acid micelles and bovine serum albumin (BSA) oxidation to similar extents as most of the other compounds in a concentration-dependent fashion. Since the aromatic nitroxides tested in this study are less toxic than BHT, these compounds may be regarded as potential, alternative sources for several applications. The mechanisms underlying the antioxidant activity of nitroxides were further confirmed by UV–Vis absorption spectroscopy experiments and macroscale reactions in the presence of radicals generated by thermolabile azo-compounds. Distribution coefficients in octanol/buffer of the nitroxides and the other compounds were also determined as a measure of lipophilicity.     

Comparison of antioxidant activity between aromatic indolinonic nitroxides and natural and synthetic antioxidants

In view of the possible employment of nitroxide compounds in various fields, it is important to know how they compare with other synthetic antioxidant compounds currently used in several industries and with naturally occurring antioxidants. To address this issue, the antioxidant activity of two aromatic indolinonic nitroxides synthesized by us was compared with both commercial phenolic antioxidants (BHT and BHA) and with natural phenolic antioxidants (alpha-hydroxytyrosol, tyrosol, caffeic acid, alpha-tocopherol). DPPH radical scavenging ability and the inhibition of both lipid and protein oxidation induced by the peroxyl-radical generator, AAPH, were evaluated. The results obtained show that overall: (i) the reduced forms of the nitroxide compounds are better scavengers of DPPH radical than butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BLT) but less efficient than the natural compounds; (ii) the nitroxides inhibit both linolenic acid micelles and bovine serum albumin (BSA) oxidation to similar extents as most of the other compounds in a concentration-dependent fashion. Since the aromatic nitroxides tested in this study are less toxic than BHT, these compounds may be regarded as potential, alternative sources for several applications. The mechanisms underlying the antioxidant activity of nitroxides were further confirmed by UV-Vis absorption spectroscopy experiments and macroscale reactions in the presence of radicals generated by thermolabile azo-compounds. Distribution coefficients in octanol/buffer of the nitroxides and the other compounds were also determined as a measure of lipophilicity.     

Antioxidant Activities of Aqueous Extract from Cultivated Fruit-bodies of Cordyceps militaris （L.） Link In Vitro

Biological antloxldants extracted from plants and fungi have potential abilities to scavenge free radicals and Inhibit lipid peroxldatlon, playing Important roles in preventing diseases, for example, cancer, and aging Induced by reactive oxygen species, which may cause oxidative damage to DNA, proteins and other macromolecules. The antloxldant potency of cultivated fruit-bodies of Cordyceps militarls （L.） Link was investigated In this study. Five established In vitro systems were employed, including the 1,1-dlphenyl-2- plcryldrazyl （DPPH） free radical scavenging, hydroxyl radical eliminating, iron chelating, Inhibition of Ilnolelc acid lipid peroxldatlon and reducing power. The aqueous extract from cultivated fruit-bodies was subjected to the test of amino acid, polysaccharlde and mannitol. Ascorblc acid （Vc）, butylated hydroxytoluene （BHT） and ethylenedlamlnetetraacetlc acid （EDTA） were used as positive controls for comparisons. Among the assays, the aqueous extract of C. mllltarls frult-bodles shows a significant scavenging effect on DPPH, eliminating the capability on hydroxyl radicals and the chelating effect on ferrous Iron. The extract also shows positive results of Inhibiting Ilnoleic acid lipid peroxldatlon and reducing power.