Antioxidant Effect of Dietary Supplement Withania somnifera L. Reduce Blood Glucose Levels in Alloxan-Induced Diabetic Rats

The phenolic compounds and flavonoids were determined from the extracts of Withania somnifera root (WSREt) and leaf (WSLEt). The WSREt has 28.26 mg/g total phenolic compounds and 17.32 mg/g flavonoids, whereas WSLEt has 5.4 mg/g total phenolic compounds and 5.1 mg/g flavonoids. The WSREt, WSLEt and glibenclamide were orally administered daily to diabetic rats for 8 weeks. After the treatment, the levels of urine sugar, blood glucose, liver glycogen, and antioxidants like vitamin C and E in plasma and superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) in liver, kidney and heart were determined. Diabetic rats showed a significant (p < 0.05) elevation in glucose and TBARS and a significant (p < 0.05) reduction in glycogen, vitamin C and E, SOD, CAT, GPx, GST, and GSH levels when compared to normal control rats. Administration of WSREt, WSLEt and glibenclamide to diabetic rats restored the levels to normal. In the light of aforesaid facts, it is suggested that the presence of phenolic compounds including flavonoids in W. somnifera root and leaf extracts and their antioxidant activity may play a vital role in reduction of blood glucose level in alloxan-induced diabetic rats.     

<Emphasis Type="Italic">In vitro</Emphasis> and <Emphasis Type="Italic">In vivo</Emphasis> Antioxidant Properties of Extracts from <Emphasis Type="Italic">Coptis chinensis</Emphasis> Inflorescence

The inflorescence of cultivated Coptis chinensis has been valued for tea production for many years in China. The antioxidant activities of C. chinensis inflorescence extracts prepared by various solvents were investigated by using several established in vitro systems: 2,2′-azinobis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS), α,α-diphenyl-β-picrylhydrazyl (DPPH) and superoxide radical scavenging assays, reducing power assay, and ferrothiocyanate (FTC) and thiobarbituric acid (TBA) assays. The results showed that the 70% ethanol extract (EE) had the strongest antioxidant activity in vitro among the various extracts. Based on the in vitro results, EE was used to evaluate the antioxidant activity of C. chinensis inflorescence in vivo. The liver and kidney of intoxicated animals showed a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels, while the malondialdehyde (MDA) level showed a significant increase. These changes were significantly reversed after treatment with EE and the standard vitamin E. Thus, the C. chinensis inflorescence may be a valuable natural source that can be applicable to food industries.     

Protective Effect of Maize Silks (Maydis stigma) Ethanol Extract on Radiation-Induced Oxidative Stress in Mice

Maize silks, dried cut stigmata of maize female flowers, are a traditional medicinal plant. This study was conducted to investigate the antioxidant effect of maize silks ethanol extract (MSE) against oxidative damage in vivo. γ-radiation was employed to induce oxidative stress in mice and the variation of malondialdehyde (MDA), glutathione/glutathione disulfide ratio (GSH/GSSG), blood cells, NF-E2-related factor 2 (Nrf2) and related antioxidant enzymes were examined. The results showed that radiation elevate levels of MDA, induce hematological abnormalities and decrease levels of GSH/GSSG and Nrf2 expression in liver and kidney. MSE administration significantly abolished elevation of MDA levels in liver, maintained hepatic GSH/GSSG ratio and ameliorated hematological abnormalities dose dependently. Moreover, MSE up-regulated the hepatic protein expression of Nrf2 dose dependently and the activities as well as protein expression of Nrf2-related antioxidant enzymes were also increased. However, the antioxidant ability of MSE seemed not to be as effective in kidney as in liver. These findings firstly proved the protective role of MSE against oxidative stress, which was in part via up-regulation of Nrf2 and seemed to be tissue specific.     

Regulatory Effects of Functional Soluble Dietary Fiber from Saccharina japonica Byproduct on the Liver of Obese Mice with Type 2 Diabetes Mellitus

Though the relationship between dietary fiber and physical health has been investigated widely, the use of dietary fiber from marine plants has been investigated relatively rarely. The Saccharina japonica byproducts after the production of algin contain a large amount of insoluble polysaccharide, which will cause a waste of resources if ignored. Soluble dietary fiber (SDF)prepared from waste byproducts of Saccharina japonica by alkaline hydrolysis method for the first time had a wrinkled microscopic surface and low crystallinity, which not only significantly reduced liver index, serum levels of aspartate aminotransferase (AST) and alanine amiotransferase (ALT), and liver fat accumulation damage to the livers of obese diabetic mice, but also activated the PI3K/AKT signaling pathway to increase liver glycogen synthesis and glycolysis. By LC-MS/MS employing a Nexera UPLC tandem QE high-resolution mass spectrometer, the 6 potential biomarker metabolites were screened, namely glycerophosphocholine (GPC), phosphocholine (PCho), pantothenic acid, glutathione (GSH), oxidized glutathione (GSSG), and betaine; several pathways of these metabolites were associated with lipid metabolism, glycogen metabolism, and amino acid metabolism in the liver were observed. This study further provided a detailed insight into the mechanisms of SDF from Saccharina japonica byproducts in regulating the livers of obese mice with type 2 diabetes and laid a reliable foundation for the further development and utilization of Saccharina japonica.     

6-BA对Hg2+胁迫下小麦幼苗渗透调节物质及抗氧化特性的影响

为探讨6-苄氨基腺嘌呤(6-BA)对Hg2+胁迫下小麦幼苗生长的调节作用,采用营养液水培法,以小麦品种807为材料,分析了叶面喷施不同浓度的6-BA对Hg2+胁迫下小麦幼苗叶片中渗透调节物质含量、抗氧化酶活性及抗氧化物质含量的影响。结果表明,50mg·L-1 HgCl2处理后,小麦幼苗叶片的可溶性糖和可溶性蛋白含量显著降低,过氧化物酶(POD)和超氧化物歧化酶(SOD)活性下降,还原型抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量显著降低。叶面喷施一定浓度的6-BA能够提高Hg2+胁迫下小麦幼苗叶片的可溶性糖和可溶性蛋白含量,显著提高小麦幼苗叶片的POD、SOD活性和AsA、GSH含量,降低脱氢抗坏血酸(DHA)和氧化型谷胱甘肽(GSSG)含量,提高小麦幼苗叶片的AsA/DHA和GSH/GSSG比值,从而缓解Hg2+胁迫对小麦幼苗生长的抑制作用。叶面喷施10mg·L-1 6-BA对缓解小麦幼苗Hg2+胁迫效果最好。     

水杨酸对低温胁迫下枇杷幼果若干生理生化指标的影响

以3年生枇杷容器苗为试验材料,研究在低温胁迫下水杨酸(SA)处理后枇杷幼果若干生理生化指标的变化.结果表明:SA能增强枇杷幼果的抗寒性,其中以70mg/L SA处理枇杷幼果的效果最好;SA处理枇杷幼果,能增强过氧化物酶(POD)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,提高还原型谷胱甘肽(CSH)和类胡萝卜素(Caro)的含量,降低丙二醛(MDA)含量,抑制叶绿素的降解.     

Analysis of free reduced and free oxidised glutathione in wheat flour

A rapid and sensitive high-performance liquid chromatography (HPLC) method is described for the determination of reduced and oxidised glutathione (GSH and GSSG, respectively) in wheat flour. The procedure, in which the various steps were optimised, involves extraction with 5% (w/v) perchloric acid (PCA) so as to prevent sulphydryl-disulphide (SH/SS) interchange reactions and to separate PCA-extractable peptides from proteins, the latter being insoluble in PCA. After S-carboxymethylation of free sulphydryl groups by alkylation with iodoacetic acid (IAA) and dinitrophenylation of free amino groups with 1-fluoro-2,4-dinitrobenzene (FDNB), the derivatives are analysed by HPLC on an amino-bonded phase silica column. Recoveries of GSH and GSSG standards added during extraction averaged 98% and 86%, respectively, and detector responses were linear up to 100 nmol GSH/g flour and 50 nmol GSSG/g flour. GSH levels in ‘straight-run’ Brabender Quadrumat Junior-milled white flours from single samples of grain of 11 U.K.-grown wheat cultivars ranged from 18 to 89 nmol/g flour and GSSG levels from 12 to 22 nmol/g flour. The ratio of GSH/GSSG varied between 0·9 and 5·9. No clear relationships were noted for this limited sample set between either the flour GSH or GSSG contents or the GSH/GSSG ratios and the bread making classifications of these cultivars. Storage of white flour samples at 4 °C for 90 days resulted in substantially reduced values for both GSH and GSSG necessitating standardisation of the time between milling and subsequent analysis.     

Green Synthesis of Silver Nanoparticles by the Cyanobacteria Synechocystis sp.: Characterization,Antimicrobial and Diabetic Wound-Healing Actions

Green nanotechnology is now accepted as an environmentally friendly and cost-effective advance with various biomedical applications. The cyanobacterium Synechocystis sp. is a unicellular spherical cyanobacterium with photo- and hetero-trophic capabilities. This study investigates the ability of this cyanobacterial species to produce silver nanoparticles (AgNPs) and the wound-healing properties of the produced nanoparticles in diabetic animals. Methods: UV–visible and FT-IR spectroscopy and and electron microscopy techniques investigated AgNPs’ producibility by Synechocystis sp. when supplemented with silver ion source. The produced AgNPs were evaluated for their antimicrobial, anti-oxidative, anti-inflammatory, and diabetic wound healing along with their angiogenesis potential. Results: The cyanobacterium biosynthesized spherical AgNPs with a diameter range of 10 to 35 nm. The produced AgNPs exhibited wound-healing properties verified with increased contraction percentage, tensile strength and hydroxyproline level in incision diabetic wounded animals. AgNPs treatment decreased epithelialization period, amplified the wound closure percentage, and elevated collagen, hydroxyproline and hexosamine contents, which improved angiogenesis factors’ contents (HIF-1α, TGF-β1 and VEGF) in excision wound models. AgNPs intensified catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities, and glutathione (GSH) and nitric oxide content and reduced malondialdehyde (MDA) level. IL-1β, IL-6, TNF-α, and NF-κB (the inflammatory mediators) were decreased with AgNPs’ topical application. Conclusion: Biosynthesized AgNPs via Synechocystis sp. exhibited antimicrobial, anti-oxidative, anti-inflammatory, and angiogenesis promoting effects in diabetic wounded animals.     

Astaxanthin Provides Antioxidant Protection in LPS-Induced Dendritic Cells for Inflammatory Control

Astaxanthin, originating from marine organisms, is a natural bioactive compound with powerful antioxidant activity. Here, we evaluated the antioxidant ability of astaxanthin on dendritic cells (DCs), a key target of immune regulation, for inflammatory control in a sepsis model. Our results showed that astaxanthin suppressed nitric oxide (NO) production, reactive oxygen species (ROS) production, and lipid peroxidation activities in LPS-induced DCs and LPS-challenged mice. Moreover, the reduced glutathione (GSH) levels and the GSH/GSSG ratio were increased, suggesting that astaxanthin elevated the level of cellular reductive status. Meanwhile, the activities of antioxidant enzymes, including glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD), were significantly upregulated. Astaxanthin also inhibited the LPS-induced secretions of IL-1β, IL-17, and TGF-β cytokines. Finally, we found that the expressions of heme oxygenase 1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) were significantly upregulated by astaxanthin in LPS-induced DCs, suggesting that the HO-1/Nrf2 pathway plays a significant role in the suppression of oxidative stress. These results suggested that astaxanthin possesses strong antioxidant characteristics in DC-related inflammatory responses, which is expected to have potential as a method of sepsis treatment.     

Improved Antioxidant and Anti-inflammatory Potential in Mice Consuming Sour Cherry Juice (<Emphasis Type="Italic">Prunus Cerasus</Emphasis> cv. Maraska)

The present investigation tested the in vivo antioxidant efficacy (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase; Gpx), lipid peroxidation (LPO) and anti-inflammatory properties (cyclooxygenase-2; COX-2) of sour cherry juices obtained from an autochthonous cultivar (Prunus cerasus cv. Maraska) that is grown in coastal parts of Croatia. Antioxidant potential was tested in mouse tissue (blood, liver, and brain), LPO (liver, brain) and anti-inflammatory properties in glycogen elicited macrophages. Additionally, the concentration of cyanidin-3-glucoside, cyanidin-3-rutinoside, pelargonidin-3-glucoside, pelargonidin-3-rutinoside and total anthocyanins present in Prunus cerasus cv. Maraska cherry juice was determined. Mice were randomly divided into a control group (fed with commercial food pellets) and 2 experimental groups (fed with commercial food pellets with 10% or 50% of cherry juice added). Among the anthocyanins, the cyanidin-3-glucoside was present in the highest concentration. These results show antioxidant action of cherry juice through increased SOD (liver, blood) and Gpx (liver) activity and decreased LPO concentration. The study highlights cherry juice as a potent COX-2 inhibitor and antioxidant in the liver and blood of mice, but not in the brain. Thus, according to our study, Prunus cerasus cv. Maraska cherry juice might potentially be used as an antioxidant and anti-inflammatory product with beneficial health-promoting properties.     

Effects of Atorvastatin on the Hypertension-Induced Oxidative Stress in the Rat Brain

Background: It is well known that the development of brain oxidative stress is one of the most serious complications of arterial hypertension that evokes brain tissue damage. The aim of this study was to examine the effects of atorvastatin treatment (20 mg/kg/day), as an antioxidant, to prevent the brain tissue oxidative stress in the hypertensive (HTN) rats. Methods: Experiments were performed in four groups of rats (n = 5 each group): sham, sham-treated, HTN and HTN treated. Rats were made HTN by aortic constriction above the renal arteries. After 30 days, rats were slaughtered under deep anesthesia to remove brain hemispheres. After tissue homogenization, enzyme activities of superoxide dismutase (SOD) and catalase (CAT), as well as glutathione (GSH) content and malondialdehyde (MDA) level were determined by biochemical methods. Results: In HTN rats, arterial blood pressure was increased about 40% and brain enzyme activities of SOD and CAT were significantly decreased compared with sham group. Induction of hypertension significantly decreased GSH content and increased MDA level of brain tissue. Treatment with atorvastatin enhanced the activity of SOD and prevented from GSH decrement during hypertension. Conclusion: Based on the findings of this study, treatment with atorvastatin might have saved the brain tissue of HTN rats from hypertension-induced oxidative stress. Key Words: Atorvastatin, Aortic coarctation, Oxidative stress, Hypertension     

增塑剂对小麦种子萌发过程中细胞程序性死亡指标的影响

为了明确增塑剂与细胞程序性死亡(PCD)的关系,用邻苯二甲酸酯类增塑剂处理小麦种子,研究增塑剂对小麦种子萌发过程中细胞程序性死亡相关指标的影响,并对增塑剂诱导细胞程序性死亡的生理生化和分子机制进行了初步探讨.结果表明,增塑剂对小麦种子萌发率有显著影响,能够抑制小麦种子萌发.增塑剂处理后小麦种子萌发过程中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性先上升后下降,同时实验后期抗坏血酸过氧化物酶(APX)活性也有类似的趋势.经DNA ladder实验证明,高浓度增塑剂处理能够引发小麦种子细胞程序性死亡.其原因可能与增塑剂促进gr、dhar以及vpe、metacaspase基因的表达有关,且随着增塑剂浓度的不断增大,各基因相对表达量变化趋势基本一致.     

Effects of temperature increase,through spring sowing,on antioxidant power and health-beneficial substances of old and new wheat varieties

The effects of heat stress on the potentially health-beneficial compounds of two old durum wheat genotypes, Timilia and Cappelli and a more recent cultivar, Claudio, were analysed following sowing in winter and in spring. Grain profiling was performed for content of: resistant and not-resistant starch, carotenoids, tripeptide glutathione, GSH and glutathione disulfide, GSSG. Hydrophilic and lipophilic grain extracts were analysed for polyphenol content and antioxidant capacity using two in-vitro assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical quenching and Fremy's salt radical quenching. The antioxidant activities of hydrophilic and lipophilic extracts determined by the two tests were not related. ANOVA and multivariate discriminant analyses showed that genotypic effects had the most significant role in the determination of grain quality. Spring sowing increased the lipophilic/hydrophilic polyphenol ratio, across all of the genotypes. It also enhanced the content of resistant starch (+68%) for Claudio and GSH (+14%) for Timilia. In contrast, if sown in winter rather than spring, Cappelli accumulated more carotenoids (+8.6%) and Timilia accumulated more resistant starch (+81%). Spring sowing had a detrimental effect on yield, but a positive effect on 1000 kernel weight. Consequently, it may lead to a net accumulation of healthy substances and not a relative increase due to grain shrivelling.     

外施海藻糖对高温胁迫下小麦幼苗膜脂过氧化的影响

在非生物胁迫条件下,海藻糖可以提高植物的抗逆性,减少逆境胁迫对植物组织的伤害,维持植物的相对正常生长。为了解其具体的作用机制,以小麦为材料,通过检测高温胁迫及室温恢复过程中丙二醛(MDA)含量、过氧化氢(H2O2)含量、超氧自由基(O·-2)含量、抗氧化物质[抗坏血酸(AsA)、还原型谷胱甘肽(GSH)]含量、抗氧化酶[超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)]活性及其基因转录的表达调控,以探究外源海藻糖对小麦幼苗抗氧化系统的影响。结果表明,在高温胁迫下外源海藻糖处理主要提高了AsA含量,增强了CAT和APX活性,同时上调了Mn-SOD、Cu/ZnSOD、CAT、POD和APX的相对表达量,从而降低了MDA及H2O2的产生。而随后的室温恢复过程基本与高温胁迫的结果一致,也提高了这些酶的基因转录水平以及AsA含量,主要差别是对抗氧化酶活性的影响,即室温恢复阶段外源海藻糖主要提高了POD和APX活性。综合来看,外源海藻糖在小麦幼苗的高温胁迫及室温恢复过程中,通过促进抗氧化酶基因的上调表达,提高抗氧化酶活性和抗氧化物质含量,以酶促和非酶促两种机制共同清除高温胁迫产生的活性氧,减少氧化胁迫的损伤,维持小麦幼苗的生长。     

黄顶菊水浸提液对小麦幼苗的生理效应

为了解黄顶菊对小麦的化感效应,研究了黄顶菊茎叶、根水浸提液对小麦根系活力、叶片细胞膜透性和抗氧化特性的影响。结果表明,随提取液质量分数的提高,小麦根系活力、SOD、POD及CAT活性逐渐降低,而叶片细胞膜透性、MDA的含量逐渐上升。从化感效应指数RI和化感综合效应指数SE比较来看,黄顶菊茎叶对小麦的化感抑制效应大于根浸提液。     

Changes in soluble carbohydrates, lipid peroxidation and antioxidant enzyme activities in the embryo during ageing in wheat grains

Soluble sugar contents and antioxidant enzyme activities were measured in the embryo of wheat (Triticum aestivum L., cv Charger) seeds throughout their storage under two conditions (45 °C and 100% relative humidity (RH), and 30 °C and 75% RH) to investigate whether grain deterioration during ageing was related to lipid peroxidation resulting in a decrease in the efficiency of the antioxidant defence system, and in changes in sugar metabolism. The half-viability period (P₅₀) was only 6 d at 45 °C and 100% RH against about 3.75 months at 30 °C and 75% RH. However, sensitivity of grains to accelerated ageing carried out at 45 °C and 100% RH increased during their pre-storage at 30 °C and 75% RH. Loss of grain viability at 45 °C and 100% RH was associated with an accumulation of H₂O₂ which was concomitant with a progressive decrease in catalase (CAT) and superoxide dismutase (SOD) activities, and with an increase in glutathione reductase (GR) activity. However, malondialdehyde content did not change, suggesting that there was no lipid peroxidation during such an ageing. In return, ageing of grains at 30 °C and 75% RH was not associated either with strong changes in CAT, SOD and GR activities or with an accumulation of H₂O₂. When there was no correlation between CAT, SOD and GR activities and seed viability, there was a linear correlation between CAT activity and seed vigour evaluated by the T₅₀ during ageing at 45 °C and 100% RH. Sugar metabolism in wheat embryo largely depended on ageing conditions. Loss of grain viability at 45 °C and 100% RH was associated with a marked decrease in sucrose (Su) and a slight increase in raffinose (Ra), and subsequently in the Ra/Su ratio. At 30 °C and 75% RH, seed ageing was associated with an increase in both sugars but with no strong increase in Su/Ra ratio. Our results suggest that ageing was associated with various mechanisms depending on the conditions of ageing, and that accelerated ageing at 45 °C and 100% RH was not the only model to consider in order to understand the mechanisms involved in seed deterioration.     

Distribution of Glutathione in Osborne Fractions as Affected by Additions of Ascorbic Acid,Reduced and Oxidised Glutathione

Kernels of the wheat class DNS were stored for 21 months at 20°C. Flours were milled before (I) and after storage (II). Doughs from II were firmer than those from I, possibly due to the decrease of reduced glutathione (GSH) from 124 to 30 nmol/g. The two flours, as well as doughs that were prepared by the addition of GSH, oxidised glutathione (GSSG) and ascorbic acid (AA), were fractionated into albumin, globulin, gliadin, and acid-extractable and acid unextractable glutenin. During kneading of flour-water doughs, endogenous GSH was preferentially bound to the acid-extractable glutenin leading to an increase of protein-glutathione mixed disulphide (PSSG). Whereas addition of GSH to a dough enhanced the amount of PSSG in the acid-unextractable glutenin. GSSG increased the extensibility of the doughs but to a lesser extent than GSH and was mainly bound to the acid-extractable glutenin, most likely by an SS/SH interchange reaction with the SH groups of the proteins. GSH and GSSG, both in the presence of AA, also became bound into the glutenin but without an impairment of the improver action of AA on dough rheology. It is discussed that the addition of AA leads to a rapid conversion of GSH into GSSG, which then becomes attached to the glutenin. The increase of total non-peptide bound cysteine (PSSC) in the acid-extractable glutenin, which was favoured by AA, can be explained by a reaction of endogenous cystine with protein SH groups.     

4个甘蔗主栽品种对干旱胁迫的生理响应

为探究短期干旱胁迫下甘蔗伸长期的生理响应,本研究以4个栽培推广面积较大的甘蔗品种‘云蔗08-1609’‘粤糖93-159’‘新台糖22号’和‘桂糖42号’为供试材料,采用人工盆栽控水法,设置正常浇水对照（土壤含水量占田间持水量的80%以上）和轻度干旱（50%~60%）、中度干旱（40%~50%）和重度干旱（30%~40%）3个干旱处理,研究不同甘蔗品种在干旱胁迫下抗氧化酶系统、抗坏血酸-谷胱甘肽（AsA-GSH）循环系统、植株受损状况以及脱落酸（ABA）含量的变化规律。结果表明：干旱胁迫导致4个甘蔗品种的SOD、POD、CAT和GR活性显著提高（P<0.05,下同）;AsA、GSH含量随着干旱时间显著上升;除‘云蔗08-1609’的GSSG表现出先升后降的趋势外,其他3个品种的GSSG含量不断上升;‘云蔗08-1609’的GSH/GSSG值不断上升,‘新台糖22号’不断下降,‘粤糖93-159’和‘桂糖42号’表现出先升后降;干旱胁迫造成4个品种的MDA和质膜透性显著增加,叶片相对含水率显著降低;除‘桂糖42号’的ABA含量表现为先上升后下降的趋势外,其他3个品种干旱胁迫下ABA含量表现为升-降-升的趋势。综上表明：干旱胁迫造成4个甘蔗品种的SOD、POD、CAT活性及GR、ABA、AsA、GSH、GSSG含量显著上升。MDA和质膜透性提高,绿叶率和叶片相对含水率下降。本研究发现不同品种甘蔗干旱胁迫下的响应规律各不相同,‘云蔗08-1609’在干旱胁迫下ABA和叶片相对含水率含量最高,SOD、CAT、POD和GR活性在干旱初期响应最快,质膜透性最小。‘新台糖22号’和‘桂糖42号’在AsA-GSH循环中具有较高的AsA、GSH、GSSG含量。‘粤糖93-159’具有较高的POD和CAT活性以及较低的MDA含量。     

Influence of humic acid derived from composted wastes of Nigeria origin on oxidative and antioxidant status of African mud catfish (Clarias gariepinus)

The utilization of organic fertilizer, a product of composted organic wastes, is being advocated in Nigeria as a solid waste management alternative. The application of such products near surface water could increase organic matter load of the aquatic environment, thus increasing the humic substance concentration that influence metal speciation and bioavailability in water. In this study, Humic Acid (HA), a major humic substance fraction, derived from composted organic wastes of Nigeria origin was evaluated for effects on the oxidative and antioxidant status of African Mud Catfish (Clarias gariepinus) exposed to different HA (100, 250, 500 and 1000 mg L(-1)) concentrations in static water culture. Lipid peroxidation was estimated via malondialdehyde (MDA) using thiobarbituric acid assay while oxidative stress was assessed spectrophotometrically, via superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT) using standard enzymatic assay techniques. Results showed that treatments increased MDA by 20 to 70% but decreased SOD, CAT and GSH by 10 to 42.56%, 43.62 to 64.09% and 9.84 to 67.68%, respectively. Negative coefficient (r) was obtained for CAT (r = - 0.491; p > 0.10), GSH (r = - 0.551; p > 0.10) versus HA concentration but correlation was positive for MDA (r = 0.998; p = 0.012) and the latter. Study revealed humic acid-mediated oxidative stress and lipid oxidation in the fish. The adverse impact was a function of humic acid concentration and an assessment of heavy metal-humic acid mixture effect on the oxidative and antioxidant status of fresh water fish is recommended.     

Micrometam C Protects against Oxidative Stress in Inflammation Models in Zebrafish and RAW264.7 Macrophages

Micrometam C is a core of novel marine compound isolated from the mangrove associates Micromelum falcatum. In this study, we investigated the protective effects of micrometam C in inflammation models in the transgenic zebrafish line Tg (corola: eGFP) and RAW264.7 macrophages. We found that micrometam C significantly suppressed the migration of immune cells in tail-cutting-induced inflammation in transgenic zebrafish and reduced lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) in both zebrafish and macrophages. In addition, micrometam C also restored LPS-induced reduction of endogenous antioxidants, such as catalase (CAT), glutathione (GSH) and superoxide dismutase (SOD). The protective effects of micrometam C were in parallel to its inhibition of NADPH oxidase and nuclear factor-kappa-binding (NF-κB) activity. Thus, the present results demonstrate that micrometam C protects against LPS-induced inflammation possibly through its antioxidant property.