Comparative antioxidant activity of nanoscale lignin prepared by a supercritical antisolvent (SAS) process with non-nanoscale lignin

Nowadays, lignin antioxidant study is a hot spot. But some properties of lignin make it hard for a wide range of application. To improve lignin antioxidant activity, we employed supercritical antisolvent (SAS) method for preparation of nanoscale lignin (0.144 ± 0.03 μm) using acetone as a solvent and supercritical carbon dioxide as an antisolvent. The nanoscale lignin was characterised by Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD). The results showed that SAS process did not result in lignin degradation or chemical structure change. Due to solubility increase, many antioxidant parameters of the nanoscale lignin were obviously enhanced, including DPPH radical scavenging activity, superoxide radical scavenging activity and reducing power. As an antioxidant, the nanoscale lignin was a better material than the non-nanoscale lignin. Our study was to promote the lignin application in animal husbandry, pharmaceutical and food processing industries.     

水提板栗壳色素对羟自由基和超氧阴离子自由基的清除作用

以水从板栗壳中提取得到板栗壳色素CSPⅡ,并以Fenton反应产生·OH模型、邻苯三酚自氧化反应产生O2-·模型,用紫外和可见分光光度法试验了CSPⅡ对模型中产生的·OH和O2-·的清除作用。结果表明CSPⅡ具有良好的清除·OH作用,且清除作用与色素的浓度呈正相关性,EC50为83.19mg/L;CSPⅡ对O2-·没有显著的清除作用。     

Alterations in antioxidant status of rats following intake of ginger through diet

Ginger is known to possess potent antioxidant and anti-inflammatory properties. Therefore, in vivo studies in rats were initiated to investigate if ginger fed through diet can improve their antioxidant status. Inbred male Wistar/NIN rats were divided into four groups containing six animals per group. The 1st group received a stock diet whereas the 2nd, 3rd and 4th groups were fed with a diet incorporating ginger powder at 0.5%, 1% and 5% levels for a period of one month. After one month of feeding, rats were sacrificed and their livers and kidneys collected for the analysis of antioxidant enzymes like superoxide dismutase (SOD), catalase and glutathione peroxidase (GSHPx), and to estimate lipid peroxidation and protein oxidation. The levels of all the three enzymes, which are the important components of antioxidative defenses, were significantly stimulated in the livers of groups fed with ginger. The significant reduction in lipid peroxidation in livers and kidneys and inhibition of protein oxidative products in livers indicated the antioxidant potential of ginger when consumed naturally through diet. The findings reported suggest that regular intake of ginger through diet can protect against oxidative tissue damage.     

Effect of processing on the antioxidant activity of millet grains

Millets are generally dehulled and subjected to a hydrothermal treatment before consumption, thus the hulls can be used as a potential source of antioxidants. Several millet grains, namely kodo, finger (Ravi), finger (local), proso, foxtail, little and pearl millet were studied. Antioxidant activities of phenolic extracts obtained from whole grains, as well as their corresponding dehulled and cooked grains and hulls were studied for their total phenolic content (TPC), radical scavenging capacity, and antioxidant activity in a β-carotene/linoleate emulsion. The phenolics present in whole grains were identified and quantified using HPLC and HPLC/MS and results were expressed as total for each of the phenolic groups. The TPC ranged from 2 to 112 μmol ferulic acid equivalents/g defatted meal. All varieties exhibited effective inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, peroxyl and superoxide radicals. Dehulling and cooking affected the TPC and radical scavenging and antioxidant activities of the grains, depending on the variety. In general, the antioxidant activity of phenolic extracts was in the order of hull > whole grain > dehulled grain > cooked dehulled grain With the exception of the two finger millet varieties, hulls of other millet grains had high TPC, thus demonstrating their superior antioxidant activity. Hydroxybenzoic acids, hydroxycinnamic acids and flavonoids in whole grains were identified as contributors to the observed effects. Therefore, dehulling of grain and hydrothermal treatments affect the phenolic content and antioxidant potential of millet grains.     

超氧化物歧化酶益生菌发酵酸奶的研究

本文研究了在不同的益生菌发酵剂配比条件下酸奶的品质和口感.双歧杆菌:嗜酸乳杆菌:保加利亚乳杆菌:嗜热链球菌比例为(10∶4∶2∶2)用于酸奶的混合发酵生产,可以使双歧杆菌活菌数达到1.5×108cfu/ml、嗜酸乳杆菌活菌数达到3.1×108 cfu/ml;采用添加低聚木糖等益生元,可以促进双歧杆菌的活菌数目提高;发酵后在LABS酸奶中添加SOD,可保持其在酸奶中较高的酶活力.SOD-LABS益生菌酸奶在4℃保存21d,SOD酶活性能保持75%以上.     

六月霜提取物清除O-·2和OH·自由基的体外实验研究

用氮蓝四唑(NBT)光还原法,对六月霜中提取物清除超氧离子自由基O-·2的效果进行了测定。结果显示,六月霜提取物对超氧离子自由基有较强的清除效果,清除效果与提取物中黄酮浓度有关,当黄酮浓度达到一定值时,对O-·2的清除效果可高达88．41％。提取物与抗坏血酸(VC)进行了对照实验,结果显示其对O-·2的清除能力比VC高。六月霜提取物在w-Cu2+-H2O2体系中,对OH·自由基的清除效果的研究显示,最高清除率为84．02％。     

磁化水对甜菜种子萌发期和幼苗期体内几种酶活性的影响

磁化水可提高甜菜种子萌发期和幼苗期体内淀粉酶活性、过氧化氢酶活性、超氧化物歧化酶活性。磁化水可提高甜菜种子的发芽势。     

Effect of bamboo oil on antioxidative activity and nitrite scavenging activity

The purposes of this study were to investigate the effects of the bamboo oil on antioxidative activity and nitrite scavenging activity in vitro and in vivo. When the bamboo oil concentration was increased from 10 to 90 μL/mL, the DPPH scavenging rate increased from 15.6 to 98.2%. However, at bamboo oil concentrations above 110 μL/mL, it was not increased. The superoxide anion radical scavenging rate increased from 54.8 to 89.1% when the bamboo oil concentration increased from 110 to 150 μL/mL. When the bamboo oil was incubated for 20 h, the linoleic acid scavenging rate was approximately 91.2%, similar to that of ascorbic acid. The glutathione production using bamboo oil in vivo was 59.0 μM/g of liver, which was about 6.5-fold higher than that of the control. In the case of the activities of glutathione peroxidase and catalase, they were 16.8 U/mg of protein and 295 KU/mg of protein, respectively, approximately 5.6-fold higher and 3.0-fold higher than that of the control. The nitrite scavenging activity was increased from 60.1 to 93.9% at pH of 1.2 when the saturation time was increased from 2 months to 8 months. However, at more than 10 months of saturation, this level was not increased. These results suggest that the bamboo oil of Phyllostachys nigra var. henonis can be used in bioactive and functional materials.     

壳聚糖涂层亲和层析在超氧化物歧化酶纯化中的应用

1前言亲和层析是蛋白质纯化中分离效率最高的技术之一。亲和配基有多种形式如单机、底物、活性染料、金属离子等。固定化金属离子亲和层析（Immobilizedmetalionaffinitychromatog’“PhyIMAC）是Porath在1975年首先研究的一种高效分离技术［‘3。IMAC和普通的亲和层析相比,具有一些优点,如亲和配基Cu’”、Zn’“价廉;可在高盐浓度下操作;稳定,容易再生。Sulkowke曾用IMAC技术分离纯化干扰素,一步可纯化产品几十倍【“,收率达90％。目前IMAC介质制备是先在软基质SePharose或SePhadex上用化学交联法弓卜螫合剂IDA（Imino…