部分TiAl基合金的抗氧化性评价

用年腐蚀深度公式计算了5种TiAl基合金在700 ℃～1 000 ℃高温条件下设计寿命为1年或半年的腐蚀程度，对其抗氧化性进行了评价，并与其它耐热材料作了比较。结果显示，二元TiAl基合金的抗氧化性强于三元TiAl-Cr合金，前者在800 ℃左右，后者低于800 ℃；二元TiAl基合金中Ti–50Al及Ti–52Al的抗氧化性优于Ti–48Al合金，三元TiAl–Cr合金中Ti–48Al–4Cr的抗氧化性优于Ti–48Al–1Cr合金。5种TiAl基合金的抗氧化性均不如Ni基合金及Ni–Al系化合物，但比Ti3Al及常规钛合金好。

反应时间对DPPH·法、ABTS+·法评价抗氧化性结果的影响

由于DPPH·法、ABTS+·法操作简单,不需要特殊的检测设备(通过反应体系颜色的改变评价试样抗氧化性),因此,常被选作抗氧化性能评价方法。用这两种方法进行抗氧化性评价时,通常用固定反应时间下算得的EC50值(自由基清除率为50%时所需试样浓度)表征抗氧化剂的抗氧化性强弱(对于DPPH·法,固定时间为30min;对于ABTS+·法,固定时间为6min),结果表明:不同抗氧化剂因其组成、结构的差异,与DPPH·、ABTS+·反应速率不同,反应到达平衡的时间不同,将反应时间固定在某一值时,可能对抗氧化剂的抗氧化性评价带来错误的判断。

真菌多糖抗氧化作用的研究进展

真菌多糖是一类低毒、安全有效、来源广泛的天然抗氧化剂新资源。近年来，真菌多糖抗氧化性的研究已经成为多糖及抗氧化剂研究的热点。本文从真菌多糖的结构、提取及抗氧化作用评价方法等方面对近年来国内外的研究进行了综述和展望，以期对真菌多糖的研究、开发和利用提供参考价值。

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 antioxidant activity of marine Agrobacterium SP. 1202

The three water-soluble polysaccharides （PI, PII and Pill）, the ethyl acetate extraction （EA） and its five fractions of petroleum ether （PeF）, ethyl acetate （EaF）, butanol （BuF）, methanol （MeF） and water （WtF） from marine agrobacterium 1202 were prepared and then subjected to antioxidant activity evaluation. The antioxidant activity was tested using the 1, 1-Diphenyl-2-picryl-hydrazyl （DPPH） free radical-scavenging assay, the hydrogen peroxide-induced luminot chemiluminescence （CL） assay and hydroxyl free radical-initiated chemiluminescence （CL） assay. All the fractions exerted significant inhibitory effects on hydrogen peroxide and hydroxyl free radical. The extracts of EA, EaF and BuF could also showed inhibition on DPPH. Among of them, the extracts of EaF showed full of antioxidant activity on the three tested system. The result suggested that the marine agrobacterium 1202 is a potential source of natural antioxidantagent.

Synthesis of Iron-Pyridoxine Complex by Solvothermal Process, Its Structural Characterization and Antioxidant Activity Evaluation

Hydroxyl radicals, superoxide anions and nitricoxide radicals are reactive species that can attack biomolecules such as DNA, lipids and proteins to cause many lifestyle-related diseases including hypertension and photoaging. This study reports the synthesis of new copper-pyridoxine and iron-pyridoxine complexes. The complexes have been synthesized and characterized by molar conductances, IR, UV-Visible, mass spectrometry, melting points and magnetic moment datas. The molecular formula of the complex is found to be Fe（py ^-）2Cl.H2O. The pyH/pyligand is coordinated to copper and iron through N atom of the pyridine ring and O atom of 5＇-CH2OH group. The Fe（III） complex is found to be paramagnetic with one unpaired electron. The antioxidant activities of the free ligand and its complexes were determined in vitro.

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.

Ferulic Acid in Paper Mulberry and Its Wastewater from Pulps Production

Wastewater from paper mulberry （Broussonetia papyrifera） pulps production was subjected to biological activities evaluations and phenolics characterization. The EtOAc extract was found to be the best antioxidant （IC50 = 0.4408 mg/mL） and tyrosinase inhibitor （IC50 = 1.6340 mg/mL） comparing to vitamin C （1C50 = 0.0011 mg/mL） and kojic acid （IC50 = 0.0244 mg/mL）, respectively, and the highest ferulic acid content （4.450 ±0.0077 ppm）. This fraction was further column chromatographed and antioxidant activity was archived （IC50 = 0.075 mg/mL） as well as tyrosinase inhibitory effect （IC50 = 0.042 mg/mL） in addition to ferulic acid （45.310 ± 0.0115 ppm）. Ferulic acid in paper mulberry was compared. Reflux with H2O gave the highest ferulic acid content （37.848 ± 1.2470 ppm） followed by a mixture of MeOH and H2O （2.002 ± 0.0370 ppm） and MeOH （1.185 ± 0.0320 ppm）, respectively. The reflux H2O was partitioned with EtOAc that extracted most of ferulic acid （256.678 ± 0.3760 ppm） and left less in the aqueous layer （9.408 ± 0.2820 ppm）.