甲硫氨酸席夫碱铜、锌、钴配合物合成及抗O^._2性能

合成了邻香草醛甲硫氨酸席夫碱及其铜、锌、钴等配合物 ,通过元素分析、摩尔电导、红外光谱、电子光谱、热分析及电子顺磁共振等手段对它们进行了表征 ,并用 EPR法探讨了它们对O· -2 的清除作用 .结果表明 ,配体与配合物均具有抗 O· -2 性能 ,配合物清除能力比配体强 。

Purification and characterization of novel antioxidant peptides of different molecular weights from mackerel Pneumatophorus japonicus protein hydrolysate

Mackerel （Pneumatophorus japonicus） proteins were hydrolyzed by five proteases： trypsin, papain, neutrase, acid protease, and flavourzyme. The hydrolysate treated by neutrase exhibited the highest antioxidant activity. Response surface methodology （RSM） was employed to optimize the hydrolysis conditions in an effort to obtain a mackerel protein hydrolysate （MPH） with the highest DPPH radical scavenging activity. The MPH was fractioned using a series of ultrafiltration membranes and five fractions, namely, MPH-I （〉10 kDa）, MPH-II （10-2.5 kDa）, MPH-III （1-2.5 kDa）, MPH-IV （0.4-1 kDa）, and MPH-V （below 0.4 kDa）, were obtained. DPPH radical scavenging activity, reducing power, hydroxyl radical scavenging activity, and the lipid peroxidation inhibition capability of these fractions were evaluated. The fractions in molecular weights 〈2.5 kDa （MPH-III, MPH-IV, and MPH-V）, which occupied 93.4% of the total fractions, showed the strongest antioxidant activity; and the antioxidant activities of the three fractions are similar to each other. Using SP Sephadex C-25 and Sephadex G-25 columns, eight fractions were obtained from the MPH （〈2.5 kDa）. The isolated peptide I （1 664 kDa） displayed the highest DPPH radical scavenging activity. Therefore, MPH is a potential source of antioxidant peptides.

Isolation and Characterization of Fucoidans from Five Brown Algae and Evaluation of Their Antioxidant Activity

In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF), and Ecklonia maxima(EMF). LJF was less in sulfate content(14.16%) and more in galactose and mannose content(1.08 and 0.68) than the documented early. EMF contained 20%–30% of sulfate and fucose, 0.97 in molar ratio which was lower than that of sulfate to other four fucoidans(1.21–1.41). AMF(162 kDa) and EMF(150 kDa) were the first two largest in molecular weight, which were followed by LJP(126 kDa), LNF(113 kDa) and LTF(105 kDa). The fucoidans isolated these algae showed a wide range of antioxidant activity in vitro. It was found that the reducing power of the isolated fucoidans was positively correlated with their sulfate content and molecular weight. In addition, LNF and LTF at low concentrations exhibited high superoxide and hydroxyl radical scavenging activity. This demonstrated that low molecular weight fucoidans may perform a high antioxidant activity.

Evaluation of Free Radicals and Antioxidant Properties of Virus Infected Food Crops in Azerbaijan

Abstract： Viral diseases are an important limiting factor in many crop production systems in Azerbaijan. Symptomatic plants in main crop-producing areas were tested by ELISA （enzyme-linked immunosorbent assay） using specific monoclonal and polyclonal antibodies. Then RCA （rolling circle amplification） of circular DNA and PCR using different specific primer pairs have indicated that the tested symptomatic plant samples were completely infected by the following viruses： Luteovirus [BLRV （Bean leaf roll virus）], Potyviruses [BCMV （Bean common mosaic virus）, BYMV （Bean yellow mosaic virus）], Bromovirus [（AMV） Alfa-alfa mosaic virus], Geminiviruses [CpCDV （ Cickpea chlorotic dwarf virus） and TYLCV （Tomato yellow leaf curl virus）] and Nanoviruses [two different FBNYV （Faba bean necrotic yellow virus） and FBNSV （Faba bean necrotic stunt virus）]. At the same time generation sites of superoxide and hydrogen peroxide radicals and activity of antioxidant enzymes were studied in the naturally infected plants.

Determined of antioxidant activity and preventing DNA damage effect of peanut polypeptides by chemiluminescence method

To estimate the antioxidant activities of Peanut polypeptides （PPs） by using a chemiluminescence （CL） method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide was determined by the Pyrogallol-Luminol system, the CuSO4-Phen-Vc-H2O2 system, and the luminol-H2O2 system, respectively. DNA damage preventing the effect of PPs was determined by the CuSO4-Phen-Vc-H2O2-DNA CL system. The results shows that PPs had good effect on the scavenging ability of superoxide anion （IC50=9.68±0.12 mg/ml）. PPs could scavenge hydroxide radical effectively （the IC50 value was 46.06±0.08 μg/ml）. PPs had a good scavenging ability on hydrogen peroxide, which had a relatively low IC50 value （0.17±0.07 mg/ml）. PPs （the IC50 value was0.72±0.11 mg/ml） were powerful on the DNA damage preventing effect. PPs possesses a good scavenging potency on ROS in different systems, but different results exist in different systems.

Antioxidative activity of protein hydrolysates from anchovy

Alcalase hydrolyzed protein from Anchovy under controlled condition, and the hydrolysates were rich in active peptides. The peptide content was determined by TCA-biuret method, and amino acid was determined by Ninhydrin. The antioxidative activity of the hydrolysates was investigated by measuring the reducing ability, the inhibition of lipoxygenase activity, and antioxidative ability in linoleic acid oxidation system. The hydrolysates exhibited high antioxidative activity. In addition, the hydrolysates scavenged 58.38% on hydroxyl radical and 46.88% on superoxide radical.

Analysis on the Oxidation Resistance of Jujube Saponin

In this paper, saponins were extracted from Northern Shaanxi＇ s big jujubes using organic solvent method and also the oxidation resistance of the extractives was analyzed. In the experiment, the crude extractives of the saponins from jujubes were obtained using ethyl alcohol soaking method and Soxhlet extraction method and also qualitatively tested using 3 color reactions, and the test result was positive; the oxidation resistance of jujube saponins was analyzed through DPPH, hydroxyl radical scavenging experiment and reducibility measurement, and the results showed that the capability of jujube saponins in DPPH free radical scavenging was enhanced along with the improvement of the to- be-test material concentration, so saponins played a significant role on hydroxyl radical scavenging and possessed certain reducibility. Northern Shaanxi＇ s big jujubes are rich in saponins and possess excellent antioxidant ability that will be enhanced along with the increase of saponins content. Thus, a basis is provided for the effective extension of the jujube industry chain.

Biochemical Mechanisms of Therapeutic and Prophylactic Effects of Bioflavonoids

In the present study to investigate the biochemical mechanisms of therapeutic and prophylactic action of bioflavonoids, carried out a comparative evaluation of antioxidant and antiproteinase properties of certain bioflavonoids standards in vitro. Therapeutic and prophylactic efficacy of individual bioflavonoids as well as herbal medicines with bioflavonoids, was examined at an experimental pathology （toxic hepatitis, dental caries, periodontitis, stomatitis, dysbiosis, diabetes Types 1 and 2, gastric ulcer, osteopenia） in Wistar line rats. Condition of organs and tissues was assessed by biochemical markers of inflammation, antioxidant and antimicrobial defense systems of animals. Research has shown the ability ofbioflavonoids in varying degrees inhibit the formation of superoxide anion radicals and malondialdehyde, recover free radicals, bind ions of Fe2＋, inhibiting the activity of proteases, such as leukocyte elastase. Established partially competitive type of trypsin and elastase activity inhibition by bioflavonoids. Was revealed a positive effect of bioflavonoids in experimental pathology on animals. Therapeutic and prophylactic effects of bioflavonoids, in our opinion, are realized through a strong antioxidant and antiprotease properties of these compounds.