Increased Level of Tetrahydro-β-Carboline Derivatives in Short-Term Fermented Garlic

In our previous study [1], we found that relatively short-term spontaneous fermentation (40 days at 60–70°C, 85–95% relative humidity) potentiates anti-oxidative properties of garlic, in which scavenging activity against hydrogen peroxide was included. Since tetrahydro-β-carboline derivatives (THβCs) that possess hydrogen peroxide scavenging activity have recently been identified in aged garlic extract, THβCs were quantitatively analyzed with liquid chromatography-mass spectrometry (LC-MS). (1R, 3S)-1-Methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (MTCC) and (1S, 3S)-MTCC were found in the fermented garlic extract whereas only trace levels of MTCCs were detected in the row garlic extract. Therefore, it is suggested that relatively short-term fermentation potentiates scavenging activity of garlic against hydrogen peroxide by forming THβCs, especially MTCCs.     

White Tea (<Emphasis Type="Italic">Camellia sinensis</Emphasis> Kuntze) Exerts Neuroprotection against Hydrogen Peroxide-Induced Toxicity in PC12 Cells

Tea is a popular beverage whose consumption is associated with prevention of certain disorders. The objective of the study was to investigate the potential neuroprotective effect of white tea extract (WTE) on hydrogen peroxide induced toxicity in PC12 cells. Cells were treated with various doses of WTE (10–250 μg/ml) before exposition to 250 μM hydrogen peroxide and cell survival was determined through the MTT and LDH assays. Oxidative stress was quantified in the cells after treatments as intracellular reactive oxygen species (ROS) production and the antioxidant activity of the extract was assessed in a cell free system in terms of free radical scavenging capacity. Results showed that WTE has a significant protective effect in the PC12 cell line against hydrogen peroxide as cell survival was significantly superior in WTE-treated cells compared to hydrogen peroxide-treated cells. A reduction on intracellular oxidative stress as well as radical scavenging properties were produced by WTE. Results suggest that WTE protects PC12 cells against H₂O₂-induced toxicity, and that an antioxidant mechanism through ROS scavenging may be in part responsible for cells neuroprotection.     

Aged Garlic Extract Scavenges Superoxide Radicals

There is increasing evidence to suggest that many degenerative or pathological processes, such as aging, cancer, and coronary heart disease, are related to reactive oxygen species and radical-mediated reactions. We examined the effectiveness of aged garlic extract (AGE), a garlic preparation rich in water-soluble cysteinyl moieties, and its component for scavenging of superoxide by using the hypoxanthine-xanthine oxidase and human neutrophils. In the hypoxanthine-xanthine oxidase system, electron spin resonance showed that aged garlic extract scavenged superoxide radicals in a dose-dependent manner up to 54%. The EC₅₀ value of aged garlic extract for the superoxide radical scavenging effect was 0.80 mg/ml. N-α-(1-deoxy-D-fructos-1-yl)-L-arginine (25.9%) and (1S, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-1,3-dicarboxylic acid (20.8%), water-soluble moieties of AGE, also exerted superoxide scavenging effects. Phorbol 12-myristate 13-acetate-activated human neutrophils produced superoxide radical of 56.6 ± 9.27 nmol/min/10⁷ cells. Aged garlic extract (3 mg/ml) significantly inhibited superoxide production in comparison to the control. These data suggest that aged garlic extract may be useful for preventing diseases associated with reactive oxygen species.     

Antioxidative and Antigenotoxic Effects of Garlic (<Emphasis Type="Italic">Allium sativum</Emphasis> L.) Prepared by Different Processing Methods

This study describes the antioxidant activities and antigenotoxic effects of garlic extracts prepared by different processing methods. Aged-garlic extract (AGE) showed a significantly higher total phenolic content (562.6 ± 1.92 mg/100 g garlic acid equivalents) than those of raw garlic extract (RGE) or heated garlic extract (HGE). The SC₅₀ for DPPH RSA in HGE was significantly the highest at 2.1 mg/ml. The SC₅₀ for SOD-like activity in garlic extracts was, in decreasing order, RGE (7.3 mg/ml) > AGE (8.5 mg/ml) > HGE (9.2 mg /ml). The ED₅₀ of AGE was the highest (19.3 μg/ml) regarding H₂O₂ induced DNA damage and its inhibition rate was 70.8%. The ED₅₀ of RGE for 4-hydroxynonenal (a lipid peroxidation product) induced DNA damage was 38.6 μg/ml, followed by AGE > HGE. Although the heat treatment of garlic tended to decrease the TPC and SOD-like activity and increased DPPH RSA, garlic, in general, has significant antioxidant activity and protective effects against oxidative DNA damage regardless of processing method.     

硫氢化钠对大蒜衰老与生理特性的影响

以大蒜(Allium stativum L.)为试验材料,研究外源H2S处理对大蒜衰老与生理特性的影响.结果表明:用浓度为0、100、500、1 000、1 500 μmol/L的H2S供体NaHS浇灌处理大蒜,与对照相比,一定浓度H2S处理下,大蒜保持较高的叶绿素含量和根系活力；尤其是T2 (500 μmol/L)处理,与对照相比,显著提高了大蒜叶片抗氧化酶SOD、POD、CAT及APX活性；较高的抗氧化酶活性有利于清除大蒜叶片内活性氧,从而减轻了其对细胞膜的破坏,表现在大蒜叶片电解质渗漏率和MDA含量降低；并且大蒜叶片保持较高自由水含量,延缓大蒜的衰老.高浓度的H2S处理,不但没有延缓大蒜的衰老,反而加剧其衰老.     

伏安极谱法测定槟榔提取物对过氧化氢自由基的清除活性

采用微分脉冲伏安法及循环伏安法测定不同溶剂(水、氯仿、正已烷、丙酮、乙酸乙酯)槟榔提取物对过氧化氢(H2O2)自由基的清除能力。结果显示,用Vc和咖啡酸作对照,不同溶剂槟榔提取物均有清除过氧化氢自由基的能力,其中乙酸乙酯提取物的最高,水提取物的次之,氯仿、正已烷和丙酮提取物的清除能力略低。表明伏安极谱法可用作评价天然植物提取物清除H2O2活性大小的一种快速检测的分析方法。     

Studies on Indian Green Leafy Vegetables for Their Antioxidant Activity

To identify the potential of green leafy vegetables (GLV) as antioxidants, methanolic extracts of Amaranthus sp., Centella asiatica, Murraya koenigii and Trigonella foenum graecum were studied for their antioxidant activity in different systems at multiple concentrations. Total antioxidant activity assessed by phosphomolybdenum method, free radical scavenging activity by 1,1-diphenly-2-picryl hydrazyl (DPPH), reducing power and ferrous ion chelating activity were determined. The GLV were analyzed for ascorbic acid, total and β-carotene and total polyphenol contents. The ascorbic acid, total carotene, β-carotene and total phenolic content (tannic acid equivalents) of the GLV ranged between 15.18–101.36, 34.78–64.51, 4.23–8.84 and 150.0–387.50 mg/100 g GLV, respectively. The extracts were found to have significantly different levels of antioxidant activities in the systems tested. The total antioxidant activity was highest in Murraya koenigii (2,691.78 μmol of ascorbic acid/g sample) and least in Centella asiatica (623.78 μmol of ascorbic acid/g sample). The extract concentration causing 50% inhibition of DPPH (IC₅₀) was determined (M. koenigii < C.asiatica < Amaranthus sp. < T. graecum). The maximum DPPH scavenging activity and reducing power was exhibited by Murraya koenigii. Multiple regression analysis showed that the relationship of total antioxidant activity, free radical scavenging activity, and reducing power with polyphenol and total and β-carotene was highly significant. Paper awarded the Young Scientist Award in Experimental Nutrition at the Young Scientist Award Session of the 39th Annual Meet of the Nutrition Society of India, Hyderabad, India on 15–16th Dec 2007.     

大蒜鳞茎浸提液对大豆种子萌发和幼苗生长的化感效应

为探明大蒜鳞茎浸提液对大豆种子萌发和幼苗生长的化感作用,通过对大豆种子进行不同质量浓度(0,20,40,80,100 g·L^-1)大蒜鳞茎浸提液的处理,测定不同处理的发芽率、发芽势、发芽指数、根长、下胚轴长、植株鲜重、SOD活性、POD活性、CAT活性和MDA含量,并计算化感觉效应指数以及综合化感效应,探明大蒜鳞茎浸提液对大豆的化感效应。结果表明:大蒜鳞茎浸提液对大豆种子萌发及幼苗生长呈现低浓度促进、高浓度抑制的双重化感效应。浸提液质量浓度为20~40 g·L^-1时,对大豆种子萌发及幼苗生长具有一定的促进作用,SOD和CAT活性显著上升,MDA含量变化不大;浸提液质量浓度为80~100 g·L^-1时,对大豆种子和幼苗表现出明显的抑制作用,SOD和POD活性开始下降,MDA含量显著增加。此外,大豆种子萌发及幼苗生长的各项指标对大蒜化感物质的敏感程度不同,以对根长的化感作用较为敏感,可作为衡量大蒜对大豆化感作用的评价指标。     

Antioxidant Activity and Phenolic Content of Betalain Extracts from Intact Plants and Hairy Root Cultures of the Red Beetroot Beta vulgaris cv. Detroit Dark Red

Betalains are water-soluble plant pigments that are widely used as food colorants, and have a wide range of desirable biological activities, including antioxidant, anti-inflammatory, hepatoprotective, anti-cancer properties. They can be produced from various plants, notably beetroot, but betalain products obtained in this way also have some undesirable properties and are difficult to standardize. A potentially attractive alternative is to use hairy root cultures. In the study reported here, we found that betalain extracts obtained from hairy root cultures of the red beetroot B. vulgaris cv. Detroit Dark Red also had higher antioxidant activity than extracts obtained from mature beetroots: six-fold higher 2,2-dyphenyl-1-picrylhydrazyl radical scavenging ability (90.7% inhibition, EC₅₀ = 0.11 mg, vs 14.2% inhibition, EC₅₀ = 0.70 mg) and 3.28-fold higher oxygen radical absorbance capacity (4,100 μM TE/g dry extract, vs 1,250 μM TE/g dry extract). The high antioxidant activity of the hairy root extracts was associated with increased concentrations (more than 20-fold) of total phenolic concomitant compounds, which may have synergistic effects with betalains. The presence of 4-hydroxybenzoic acid, caffeic acid, catechin hydrate, and epicatechin were detected in both types of extract, but at different concentrations. Rutin was only present at high concentration (1.096 mg.g⁻¹ dry extract) in betalain extracts from the hairy root cultures, whereas chlorogenic acid was only detected at measurable concentrations in extracts from intact plants.     

Aged Garlic Extract Attenuates Cerebral Damage and Cyclooxygenase-2 Induction after Ischemia and Reperfusion in Rats

Different garlic products reduce the cerebral ischemic damage due to their antioxidant properties. In this work, we investigated the effect of aged garlic extract (AGE) on cyclooxygenase-2 (COX-2) protein levels and activity, and its role as a possible mechanism of neuroprotection in a cerebral ischemia model. Animals were subjected to 1 h of ischemia plus 24 h of reperfusion. AGE (1.2 ml/kg weight, i.p.) was administered at onset of reperfusion. To evaluate the damage induced by cerebral ischemia, the neurological deficit, the infarct area, and the histological alterations were measured. As an oxidative stress marker to deoxyribonucleic acid, 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were determined. Finally, as inflammatory markers, TNFα levels and COX-2 protein levels and activity were measured. AGE treatment diminished the neurological alterations (61.6%), the infarct area (54.8%) and the histological damage (37.7%) induced by cerebral ischemia. AGE administration attenuated the increase in 8-OHdG levels (77.8%), in TNFα levels (76.6%), and in COX-2 protein levels (73.6%) and activity (30.7%) induced after 1 h of ischemia plus 24 h of reperfusion. These data suggest that the neuroprotective effect of AGE is associated not only to its antioxidant properties, but also with its capacity to diminish the increase in TNFα levels and COX-2 protein expression and activity. AGE may have the potential to attenuate the cerebral ischemia-induced inflammation.     

An Ethanol Extract Derived from Bonnemaisonia hamifera Scavenges Ultraviolet B (UVB) Radiation-Induced Reactive Oxygen Species and Attenuates UVB-Induced Cell Damage in Human Keratinocytes

The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB)-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE) scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO₄ + H₂O₂), both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS) that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280–320 nm). These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components.     

Valorization of the whole grains of Triticum aestivum L. and Triticum vulgare L. through the investigation of their biochemical composition and in vitro antioxidant,anti-inflammatory,anticancer and anticalpain activities

Two locally grown wheat species named Triticum aestivum L. and Triticum vulgare L. were studied for their phytochemical contents and their biological activities. T. vulgare presented the highest amounts of total phenolic compounds and ascorbic acids while T. aestivum was found to be rich in flavonoids, flavonols, proanthocynidins and ortho-diphenols. Eleven carotenoids were identified in T. vulgare where the most dominant compounds belongs to α-carotene and its derivatives while T. aestivum presented seven carotenoids. This later presented the highest DPPH radical scavenging activity and exhibited a strong reducing power in FRAP, phosphomolybdenum, hydrogen peroxide and reducing power assays. T. vulgare extract was found to be effective in metal chelating power and in scavenging nitric oxide radical. No significant differences in scavenging ABTS and hydroxyl radicals were noted between the two wheat species. T. aestivum inhibited xanthine oxidase and ROS production and showed the best cytotoxic effect while T. vulgare extract exhibited anti-calpain activity.     

<Emphasis Type="Italic">In vitro</Emphasis> Antioxidant Activity of Aged Extracts of some Italian <Emphasis Type="Italic">Allium</Emphasis> Species

Antioxidant activity of fresh Allium sativum L. (garlic) is well known and is mainly due to unstable and irritating organosulphur compounds. Fresh garlic extracted over a prolonged period (up to 20 months) produces odourless aged garlic extract (AGE) containing stable and water soluble organosulphur compounds that prevent oxidative damage by scavenging free radicals. The aim of this study was to investigate the in vitro antioxidant activity of aged (up to 20 months) 15% hydroethanolic extracts of different parts (bulbs, bulblets, flower bulblets, flowers, and leaves) of three Allium spontaneous species which are endemic for Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L., Allium roseum L. and to compare it with the in vitro antioxidant activity of aged 15% hydroethanolic extracts of bulbs and leaves of garlic. The antioxidant potential of aged extracts of all species has been evaluated using two different spectrophotometric assays: 2,2-diphenylpicrylhydrazyl (DPPH) test and the ferric reducing/antioxidant power (FRAP) assay. Furthermore the polyphenol content was determined. The aged extracts obtained from the leaves showed the best antioxidant activity, followed by flowers and then by bulbs in both used tests, while flower bulblets and bulblets exhibited lower results or no activity. The polyphenol content was generally directly correlated with antioxidant/antiradical activity. This study confirms the data obtained in previous researches, the wild-type species of Allium and in particular organs other than bulbs are more active and efficacious than garlic bulb. Surely leaves of these Allium spp. deserve special attention.     

花生疮痂病菌毒素的致病作用及其生理生化机制研究

       花生疮痂病菌（Elsinoë arachidis（ Bitauc. & Jenkins） Rossman & W.C. Allen）所产生的痂囊腔菌素（Elsinochrome，ESC）为苝醌类光敏性真菌毒素，在致病过程中起着重要的作用，为探索其作用机制，本文研究了毒素提取液接种后寄主体内活性氧含量、活性氧清除酶系的响应动态及质膜过氧化程度。结果表明，接种毒素提取液后，花生叶片内超氧阴离子（O2-）和过氧化氢（H2O2）含量激增，接种8h含量分别达1482.99 U·L-1和25.25μmol·g-1，为清水对照的10倍和40倍。活性氧清除酶SOD，CAT和POD的活性峰值出现于接种后48h，分别为78.00 U·mg -1，16.20 U·mg -1和63.73 U·mg -1，随后下降至对照水平。MDA含量于72h出现峰值，含量为5.44 μmol·g -1，膜透性随接种时间增加而上升，96h高达80%。ESC通过产生大量活性氧，导致寄主体内质膜过氧化程度增加，膜损伤加剧，最终细胞死亡，为花生疮痂病重要的致病因子。     

Volatile Compounds and Antioxidative Activity of <Emphasis Type="Italic">Porophyllum tagetoides</Emphasis> Extracts

Porophyllum tagetoides is an annual warm-weather herb that has an intense typical smell. Its leaves are commonly used in soup preparation and traditional medicine for treatment of inflammatory diseases. Its volatile compounds and antioxidant properties were evaluated in crude, aqueous and ethanol leaf extract and an oil emulsion using different antioxidant assays in vitro, such as: DPPH radical scavenging activity, redox potential, polyphenol content, reducing power and optical density. A high antioxidative activity was found when comparing leaves with stems. The crude extract from leaves showed a very high reducing power (2.88 ± 0.20 O.D.) and DPPH radical-scavenging activity (54.63 ± 4.80%), in concordance with a major concentration of vitamin C (23.97 ± 0.36 mg/100 g). Instead, the highest polyphenol content (264.54 ± 2.17 mg GAE/g of sample) and redox potential (561.23 ± 0.15 mV) were found by the ethanol and aqueous extract, respectively. Aldehydes and terpenes such as nonanal, decanal, trans-pineno, β-myrcene and D-limonene were the major volatiles found. This study suggests that Porophyllum tagetoides extracts could be used as antioxidants.     

双氧水脱色对油茶粕蛋白结构和功能特性的影响

为了除去油茶粕蛋白的色素,添加体积分数为4%的双氧水在40℃下作用蛋白提取液1h可取得较好的脱色效果,但双氧水脱色对油茶粕蛋白结构和功能的影响需要进一步研究。本文通过测定变性温度、表面疏水性和巯基的含量,分析红外光谱、X射线衍射峰、微观形貌等研究脱色前后油茶粕蛋白结构和功能的变化。结果显示:双氧水脱色使油茶粕蛋白的表面疏水性上升,巯基含量下降,二硫键含量基本不变;通过红外光谱分析,双氧水脱色减弱了油茶粕蛋白化学键强度,但没有影响油茶粕蛋白基本骨架,微观结构基本相似,油茶粕蛋白的X射线衍射峰的位置和强度基本一致,热变性温度升高,双氧水没有改变油茶粕蛋白的等电点,但油茶粕蛋白的溶解度、乳化性、乳化稳定性、起泡能力和泡沫稳定性均下降,持油性和持水性上升。本研究结果表明双氧水脱色未明显改变油茶粕蛋白的结构,但其功能性质受到一定影响。     

Differential Expression of Two Cytosolic Ascorbate Peroxidases and Two Superoxide Dismutase Genes in Response to Abiotic Stress in Rice

Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we report the responses of cytosolic SOD (cSOD; sodCc1 and sodCc2) and cytosolic APX (cAPX; OsAPX1 and OsAPX2) genes to oxidative and abiotic stress in rice. RNA blot analyses revealed that methyl viologen treatment caused a more prominent induction of cAPXs compared with cSODs, and hydrogen peroxide t...     

Synthesis and characterization of acrylic fibers-<Emphasis Type="Italic">g</Emphasis>-polyacrylamide

Graft copolymerization of acrylamide onto commercial acrylic fibers was carried out using benzoyl peroxide as a free-radical initiator in aqueous medium within the 75–95 °C temperature range. In this study, the effects of initiator and monomer concentration, the amount of fiber, polymerization time, and temperature on the graft yield were investigated. The optimum concentration for initiator was found to be 2.0×10⁻³ mol/l and the optimum temperature of 85 °C. The activation energy of the reaction was calculated to as 35.81 kJ/mol at the temperature interval of 75–95 °C. The structures and morphologies characterization of grafted fibers was investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The thermogravimetric analysis data showed that the thermal stability of the acrylic fibers increased with graft yield. The scanning electron photographs showed that the homogeneous appearance of the fiber surface changed and a shell-like heterogeneous structure occurred at the surface with an increasing degree of grafting. The moisture content, water absorption, dyeability, and antimicrobial activity of grafted acrylic fibers were also reported. The results showed that grafting of polyAAm improved the moisture contain, water absorption, dyeability, and antimicrobial activity of fiber.     

Model system for mechanistic study of catalytic bleaching of cotton

We have developed a homogeneous model system to study the mechanism of hydrogen peroxide bleaching using [Mn₂O₃(N,N′,N″-trimethyl-1,4,7-triazacyclononane)₂](PF₆)₂ (MnTMTACN) as catalyst. The primary model pigment examined is morin (3,5,7,2′,4′-pentahydroxyflavone) owing to its presence in native cotton fiber. Additionally, a series of model compounds with systematic structural differences are examined in order to facilitate the development of a mechanistic understanding of the bleaching system. The pigment oxidative degradation reaction is monitored by UV-Vis spectrophotometry. The influence of pH is examined in both homogeneous and heterogeneous model systems. The use of MnTMTACN catalyst enables low-temperature hydrogen peroxide bleaching of cotton fabric at slightly lower pH values.     

吲哚丁酸的体外抗氧化活性研究

研究吲哚丁酸的体外抗氧化活性,包括DPPH自由基、羟基自由基和过氧化氢的清除能力,以及金属螯合活性和还原力。结果表明,吲哚丁酸具有显著的抗氧化活性,且与吲哚乙酸相当,其对DPPH自由基和羟自由基清除作用、螯合力、还原能力均高于萘乙酸和2,4-二氯苯氧乙酸,而对Fe2+的络合能力与没食子酸无显著差异。