AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cer...AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.展开更多
Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their c...Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their chemical properties and spectroscopic analyses, including extensive 2D NMR experiments. Compound 2 showed strong DNA cleavage activity, and compounds 1, 2 and 10 (2, 3, 4′, 5_tetrahydroxy_ trans _stilbene_2_O_β_ D _glucopyranoside) exhibited significant inhibition of lipid peroxidation.展开更多
[ Objective] The aim of this study was to discuss the effect of antioxidants and lipid peroxidation from pea crops of plateau. [ Method] SOD enzyme liquid from pea crops of plateau was extracted by means of protein co...[ Objective] The aim of this study was to discuss the effect of antioxidants and lipid peroxidation from pea crops of plateau. [ Method] SOD enzyme liquid from pea crops of plateau was extracted by means of protein concentration assay, enzyme activity assay and antioxidant activity determination by DPPH method, peroxide activity inhibition of in vitro tissues from mice by homogenate MDA colorimetry method and lipid peroxidation assay of in vitro tissues. [ Result ] IC50 of the crude enzyme liquid extracted from pea on DPPH was 55.16 mg/L, while the scavenging rate of the crude enzyme liquid was lower than that of ascorbic acid, tea polyphenol and citric acid with the same concentration. The synergistic effect was found in ascorbic acid and crude enzyme liquid, but the synergism of ascorbic acid was better than that of citric acid. IC50 of SOD enzyme liquid extracted from pea on DPPH was 11.1 mg/L, which was better than that of tea polyphenol and closely similar to that of ascorbic acid. SOD enzyme liquid extracted from pea had an inhibitory effect on MDA production from in vitro tissues such as liver, kidney and heart, especially for a significantly inhibitory effect on MDA from liver in vitro. When the concentration was 0.25 mg/ml, the inhibition rate reached 78.3%, and then the inhibition rate increased little with the concentration incresas, while its effect on heart and kidney were inferior. [ Conclusion] SOD crude enzyme liquid and SOD enzyme liquid extracted from pea all have certain DPPH scavenging capacity, while SOD enzyme liquid extracted from pea has an inhibitory effect on lipid peroxidation.展开更多
The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the acti...The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the activities of superoxide dismutase (SOD) and GSH-peroxidase in the liver cytosol of mice, but showed no significant effect on the activity of catalase, and one of its major constituents, 4-methoxy-1-methyl-2-quinolone (MMQ) increased the activity of SOD in liver tissue of mice intoxicated with FeCl2-ascorbic acid (AA)-ADP in vivo. Various constituents isolated from the root of title plant inhibited the lipid peroxidation in rat liver homogenate, which was in vitro induced by FeCl2-ascorbic acid, CCl4-NADPH, or ADP- NADPH. Of the test compounds, MMQ and its derivatives integriquinolone were similar to (-tocopherol in inhibiting MDA production in rat liver microsomes induced by Fe2+-ascorbate, CCl4-NADPH, or ADP-NADPH.展开更多
AIM: To investigate the anti-lipid peroxidation and protection of liver mitochondria against injuries in mice with liver damage by picroside Ⅱ. METHODS: Three animal models of liver damage induced by carbon tetrachlo...AIM: To investigate the anti-lipid peroxidation and protection of liver mitochondria against injuries in mice with liver damage by picroside Ⅱ. METHODS: Three animal models of liver damage induced by carbon tetrachloride (CCl4: 0.1 mL/10 g, ip), D-galactasamine (D-GaIN: 500 mg/kg, ip) and acetaminophen (AP: 0.15 g/kg, ip) were respectively treated with various concentrations of picroside Ⅱ (5, 10, 20 mg/kg, ig). Then we chose the continuously monitoring method (recommended by International Clinical Chemistry League) to analyze serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values, Marland method to detect the activity of manganese-superoxide dismutase (SOD) in liver mitochondria, TBA colorimetry to determine the content of malonicdialdehyde (MDA) in liver tissue, DTNB method to evaluate the activity of glutathioneperoxidase (GSH-Px) and Lowry method to detect protein level in liver tissue. Meanwhile, effects of picroside Ⅱ on the activity of ATPase and swelling extent of mitochondria in hepatocytes damaged by AP were also evaluated. RESULTS: Picroside Ⅱ could significantly prevent liver toxicity in the three models of liver damage. It decreased the high levels of ALT and AST in serum induced by the administration of CCl4, D-GaIN and AP, reduced the cellular damage of liver markedly, and appeared to be even more potent than the positive control drug of biphenyl dimethyl dicarboxylate pilules (DDB). In groups treated with different doses of picroside Ⅱ, compared to the model group, the content of MDA in serum decreased evidently, whereas the content of SOD and GSH-Px increased in a dose dependent manner, and the difference was statistically significant. Further, in the study of AP model, picroside Ⅱ inhibited AP-induced liver toxicity in mice, enhanced the activity of ATPase, improved the swelling extent of mitochondria and helped to maintain a normal balance of energy metabolism. CONCLUSION: Picroside II can evidently relieve hepatocyte injuries induced by CCI4, D-GaIN and AP, help scavenge free radicals, protect normal constructions of mitochondria membrane and enhance the activity of ATPase in mitochondria, thereby modulating the balance of liver energy metabolism, which might be part of the mechanisms of hepatoprotective effects of picroside Ⅱ.展开更多
Antioxidants are used to minimize lipid oxidation. Antioxidants can act as metal chelators and free radical or oxygen scavengers, which can slow the progression of lipid oxidation. Lipid oxidation may have negative ef...Antioxidants are used to minimize lipid oxidation. Antioxidants can act as metal chelators and free radical or oxygen scavengers, which can slow the progression of lipid oxidation. Lipid oxidation may have negative effects on the quality of meat and meat products, causing changes in sensory attributes such as color, texture, odor and flavor, and nutritional quality. Several synthetic antioxidants have been used to successfully prevent lipid oxidation in the meat industry, but consumers are concerned about the health risks related to consumption of some synthetic antioxidants. Therefore, there has been a growing interest in natural antioxidants. Nowadays, compounds obtained from natural sources such as grains, oilseeds, spices, fruit and vegetables have been investigated to decrease the lipid oxidation. In this review, the potential effects of natural antioxidants were evaluated that are widely used in meat and meat products.展开更多
Objective: To estimate the oxidative stress and oxidative damage induced by abnormal free radical reactions in IgA nephropathy (IgAN) patients' bodies. Methods: Seventy-two IgA N patients (IgANP) and 72 healthy ad...Objective: To estimate the oxidative stress and oxidative damage induced by abnormal free radical reactions in IgA nephropathy (IgAN) patients' bodies. Methods: Seventy-two IgA N patients (IgANP) and 72 healthy adult volunteers (HAV) were enrolled in a random control study design, in which the levels of nitric oxide (NO) in plasma, lipoperoxide (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and β-carotene (β-CAR) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric mothods. Results: Compared with the HAV group, the averages of NO in plasma, and LPO in plasma and in erythrocytes in the IgANP group were significantly increased (P<0.0001), while those ofVC, VE and β-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the IgANP group were significantly decreased (P<0.0001). Linear correlation analysis showed that with the increase of the values of NO, and LPO in plasma and in erythrocytes, and with the decrease of those ofVC, VE, β-CAR,SOD, CAT and GPX in the IgAN patients, the degree of histological damage of tubulointerstitial regions was increased gradually (P<0.0001); and that with the prolongation of the duration of disease the values of NO, and LPO in plasma and erythrocytes were increased gradually, while those of VC, VE, β-CAR, SOD, CAT and GPX were decreased gradually (P<0.005). The discriminatory correct rates of the above biochemical parameters reflecting oxidative damage of the IgAN patients were 73.8%-92.5%, and the correct rates for the HAV were 70.0%-91.3% when independent discriminant analysis was used; and the correct rate for the IgAN patients was increased to 98.8%, the correct rate for the HAV was increased to 100% when stepwise discriminant analysis was used. The above biochemical parameters' reliability coefficient (alpha) were used to estimate the oxidative damage of the IgAN patients as 0.8145, the standardized item alpha=0.9730, F=53273.5681, P<0.0001. Conclusions: A series of free radical chain reactions caused serious pathological aggravation in the IgANP' bodies, thus resulting in oxidative damage in their bodies. In treating IgANP, therefore, it is necessary that suitable dose antioxidants should be supplemented to them so as to alleviate the oxidative damage in their bodies.展开更多
The aim of this study was to compare the effects of waterbome copper (Cu) and cadmium (Cd) on survival, anti-oxida- tive response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Exper...The aim of this study was to compare the effects of waterbome copper (Cu) and cadmium (Cd) on survival, anti-oxida- tive response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals (initial weight: 7.49 g±0.01 g) were exposed to graded concentrations of waterborne Cu (0.02, 0.04, 0.06, 0.08 mg L-1) or Cd (0.025, 0.05, 0.25, 0.5 mgL-1) for 28 days, respectively. Activities of the anti-oxidative enzymes (catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione (GSH) and malondiadehyde (MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L-1 and 0.08 mgL-1 Cu caused 100% death of abalone on the 21st, 10th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopan- creas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense against Cu or Cd. In conclusion, anti-oxidative mechanism in abalone to resist waterborne Cu did not follow the same pattern as that for waterborne Cd.展开更多
The present study evaluated the ef fects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm mot...The present study evaluated the ef fects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm motility and the activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GPx), glutathione reductase(Gr), and lipid peroxidation(measured via malondialdehyde(MDA) content) were determined after the milt was stored at 4°C for 12 h, cryopreserved without cryoprotectant in 12% propylene glycol(PG), cryopreserved in 12% PG+0.1 mol/L trehalose, or cryopreserved in 12% PG spermatozoa but centrifuged to decant the supernatant prior to cryopreservation(only sperm cells were cryopreserved). After chilled storage or cryopreservation, the SOD, CAT and GPx activities were reduced in sperm cells and increased in seminal plasma in almost all treatments; sperm motility parameters were also decreased. However, the addition of trehalose into the cryoprotectant could signifi cantly improve the postthaw sperm quality as revealed by the sperm average path velocity. This improvement might be attributed to the function of trehalose in scavenging reactive oxygen species. Chilled storage and cryopreservation had signifi cant eff ects on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod.展开更多
The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxida...The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxidation and development of off-flavor for over 50 years. However, the literature has expressed safety concerns and health risks (toxic and carcinogenic effects) associated with the use of synthetic antioxidants recently. Natural antioxidative substances from the polyphenols of edible plants are believed to be safer and may provide with additional health benefits and more effective compared to synthetic antioxidants. Due to the fact that natural antioxidants are additives that people mixed with food and consumed for centuries, they are known to be safe by the consumer. Therefore, it is an area worth to investigate due to consumer concerns about health. In the literature, there are many studies showing that the natural antioxidants have important antioxidant effect. Plants (oil seeds, cereals, vegetables, fruits, herb and spices), compounds from animal source (peptides and amino acids), enzymes and some microorganisms are important natural antioxidants. Plant extracts have been widely used to retard lipid oxidation in foods during frying and accelerated storage processes. They were found as strong antioxidant sources due to their high contents of phenolic compounds. There are countless studies about natural antioxidants. However, they have not been investigated completely by means of toxicology.展开更多
AIM: Reactive oxygen species (ROS) can induce carcinogenesis via DNA injury. Both enzymatic and non-enzymatic parameters participate in cell protection against harmful influence of oxidative stress. The aim of the pre...AIM: Reactive oxygen species (ROS) can induce carcinogenesis via DNA injury. Both enzymatic and non-enzymatic parameters participate in cell protection against harmful influence of oxidative stress. The aim of the present study was to assess the levels of final lipid peroxidation products like malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE) in primary colorectal cancer. Moreover, we analysed the activity of main antioxidative enzymes, superoxide dismutase (Cu, Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GSSRG-R) and the level of non-enzymatic antioxidants (glutathione, vitamins C and E). METHODS: Investigations were conducted in 81 primary colorectal cancers. As a control, the same amount of sample was collected from macroscopically unchanged colon regions of the most distant location to the cancer. Homogenisation of specimens provided 10% homogenates for our evaluations. Activity of antioxidant enzymes and level of glutathione were determined by spectrophotometry. HPLC revealed levels of vitamins C and E and served as a method to detect terminal products of lipid peroxidation in colorectal cancer. RESULTS: Our studies demonstrated a statistically significant increase in the level of lipid peroxidation products (MDA-Adc. muc.-2.65±0.48 nmol/g, Adc.G3-2.15±0.44 nmol/g, clinical IV stage 4.04±0.47 nmol/g, P<0.001 and 4-HNE-Adc.muc. -0.44±0.07 nmol/g, Adc.G3-0.44±0.10 nmol/g, clinical IV stage 0.52±0.11 nmol/g, P<0.001) as well as increase of Cu,Zn-SOD (Adc.muc.-363±72 U/g, Adc.G3-318?8 U/g, clinical IV stage 421±58 U/g, P<0.001), GSH-Px (Adc.muc. -2143±623 U/g, Adc.G3-2005±591 U/g, clinical IV stage 2467±368 U/g, P<0.001) and GSSG-R (Adc.muc.-880±194 U/g, Adc.G3-795±228 U/g, dinical IV stage 951±243 U/g, P<0.001) in primary tumour comparison with normal colon (MDA-1.39±0.15 nmol/g, HNE-0.29±0.03 nmol/g, Cu, Zn-SOD-117±25 U/g, GSH-Px-1723±189 U/g, GSSG-R-625±112 U/g) especially in mucinous and G3-grade adenocarcinomas as well as clinical IV stage of colorectal cancer. We also observed a decrease of CAT activity (Adc.muc. -40±14 U/g, clinical IV stage 33±18 U/g vs 84±17 U/g, P<0.001) as well as a decreased level of reduced glutathione (clinical IV stage 150±48 nmol/g vs 167±15 nmol/g, P<0.05) and vitamins C and E (vit. C-clinical IV stage 325±92 nmol/g vs 513?4 nmol/g, P<0.001; vit. E-clinical IV stage 13.3±10.3 nmol/g vs 37.5±5.2 nmol/g). CONCLUSION: Colorectal carcinogenesis is associated with serious oxidative stress and confirms that gradual advancement of oxidative-antioxidative disorders is followed by progression of colorectal cancer.展开更多
The antioxidant activities of the ethyl acetate fraction and aqueous extract of unripe fruit of Carica papaya were compared and investigated in vitro using thiobarbituric reactive species (TBARS) assay, total phenol...The antioxidant activities of the ethyl acetate fraction and aqueous extract of unripe fruit of Carica papaya were compared and investigated in vitro using thiobarbituric reactive species (TBARS) assay, total phenol content, evaluation of reactive oxygen species (ROS) in liver mitochondria, Fe2+ chelating and 2,2-diphenyl-lpicrylhydrazyl (DPPH) scavenging activities. Both extracts had high antioxidant properties and could inhibit FeE+ and sodium nitroprusside lipid peroxidation in the liver. Total phenol content of ethyl acetate fraction and aqueous extract were 4.50 ±2.26 and 1.21±3.12 mg/g, respectively. Both extracts had a maximal effect at the lowest concentrations tested (15 μg/mL for ethyl acetate and 150 μg/mL for the aqueous). Ethyl acetate fraction showed that the highest values of antioxidant activity is probably associated with its high phenolic content, Fe2+ chelating and DPPH scavenging activities. It is therefore concluded that ethyl acetate fraction and to a less extent the aqueous fractions are potent inhibitor of lipid peroxidation.展开更多
Germinating wheat (Triticum aestivum L.) seeds were exposed to CdCI2 (50, 100 and 200 μM) for 48 h and some aspects of oxidative metabolism was assessed in the embryonic tissues. The germination percentage and th...Germinating wheat (Triticum aestivum L.) seeds were exposed to CdCI2 (50, 100 and 200 μM) for 48 h and some aspects of oxidative metabolism was assessed in the embryonic tissues. The germination percentage and the soluble protein content of the embryonic tissues were found to decrease with increasing of Cd concentration. There was elevation in superoxide dismutase (SOD) and decline in catalase (CAT) and peroxidase (POX) activities. The increasing of lipid peroxidation levels indicated the prevalence of oxidative stress in the tissues which was probably due to the alteration of antioxidative enzymes activities. The adding of ascorbate, along with CdCl2, has resulted in restoration of the Cd induced decline in CAT activity. Weakening in H2O2 detoxification system seems to be the principal reason behind Cd induced oxidative stress in germinating seeds. Thus, imposition of oxidative stress might be the consequence of cadmium stress and this finding may help in elucidating the mechanisms underlying cadmium mediated toxicity in germinating seeds.展开更多
Green tides have occurred every year from 2007 to 2014 in the Yellow Sea. Ulva prolifera (Mtiller) J. Agardh has been identified as the bloom-forming alga, co-occurring with U. intestinalis. We observed distinct str...Green tides have occurred every year from 2007 to 2014 in the Yellow Sea. Ulva prolifera (Mtiller) J. Agardh has been identified as the bloom-forming alga, co-occurring with U. intestinalis. We observed distinct strategies for both algal species during green tides. U.prolifera exhibited a high abundance initially and then decreased dramatically, while U. intestinalis persisted throughout. The antioxidant system responses of these two macroalgae were compared in the late phase of a green tide (in-situ) and after laboratory acclimation. Lipid peroxidation and antioxidant system responses differed significantly between the two. Malondialdehyde and hydrogen peroxide contents increased significantly in-situ in U. prolifera, but not in U. intestinalis. In U. prolifera, we observed a significant decrease in total antioxidant ability (T-AOC), antioxidant enzymes (SOD and Apx), and non-enzyme antioxidants (GSH and AsA) in-situ. U. intestinalis showed the same pattern of T-AOC and SOD, but its Gpx, Apx, and GSH responses did not differ significantly. The results suggest that U. prolifera was more susceptible than U. intestinalis to the harsh environmental changes during the late phase of a Yellow Sea green tide. The boom and bust strategy exhibited by U. prolifera and the persistence of U. intestinalis can be explained by differences in enzyme activity and antioxidant systems.展开更多
This study aimed to purify and determine antioxidant activities of different fractions obtained during the purification process of phycocyanin from Spirulina platensis. The dried powder of Spirulina platensis, after g...This study aimed to purify and determine antioxidant activities of different fractions obtained during the purification process of phycocyanin from Spirulina platensis. The dried powder of Spirulina platensis, after ground with sands, was extracted with 50 mM sodium phosphate buffer at pH 6.8 before centrifuged to precipitate unwanted proteins. Then the supernatant was separated by celit column to obtain semi-pure phycocyanin and further purified by treated with ammonium sulfate. The purity of phycocyanin was monitored by measuring the absorbance spectrum from 200 to 700 nm. Its purity ratio A620A280 was determined. The antioxidant activities of the obtained phycocyanin were determined by 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) assay and lipid peroxidation (linoleie acid) assay. The purity ratio of phycocyanin in the Spirulina crude extract was 0.36 and increased to 2.68 after purification. The fraction with the highest purity ratio of phycocyanin demonstrated the hightest antioxidant activities. For ABTS assay, it presented the Vitamin C Equivalent Antioxidant Capacity (VCEAC) value of 0.0405 ±0.0002 mg of ascorbic acid/mg of sample and the Trolox Equivalent Antioxidant Capacity (TEAC) value of 0.0485 ±0.0002 mg oftrolox/mg of sample respectively. The result from lipid peroxidation assay exhibited IC50 value of 5.9336 ±0.2565 mg/mL. The purification of Spirulinaplatensis crude extract obtained from this study increased the purity ratio of phycocyanin and its antioxidant activities. This will be further investigated for the development into anti-aging cosmetic products.展开更多
Two new 2-substituted thiazolidine-4(R)-carboxylic acids (TCAs), 2-glusosaminal-TCA (GIcNH2Cys) and 2-N-acetyl-glueosanlinal-TCA (GlcNAeCys), were synthesized. Their protective effects against liver toxicity i...Two new 2-substituted thiazolidine-4(R)-carboxylic acids (TCAs), 2-glusosaminal-TCA (GIcNH2Cys) and 2-N-acetyl-glueosanlinal-TCA (GlcNAeCys), were synthesized. Their protective effects against liver toxicity induced by acetaminophen (APAP) were investigated in a mice model. The resuits demonstrate that administration of TCAs ( i. p. , 800 mg/kg) 30 min after APAP challenge efficiently decrease ALF, AST, and LDH levels in liver. GlcNAcCys shows the best proteetive eftects, decreasing ALT, AST and LDH levels to 63%, 18.4% and 37% of the APAP group respectively. Comparison with the control showed that APAP greatly decreases total sulfhydlyl (T-SH) levels (43%), non-protein hound sulfhydryl (NP-SH) levels (50%) and total antioxidative capabilities (57%) in the liver 24 hr after challenge. TCAs treatments 30min after APAP challenge significantly elevate sulfhydryl levels and total antioxidative capabilities. APAP administration also markedly (P 〈 0.05) increases liver lipid peroxidation to 1.65 and 1.17 times that of the control 4 hr and 24 hr after APAP administration respectively. TCAs treatments can inhibit lipid peroxidation as measured by decreased malondialdehyde (MDA) contents in liver. The histopathological results also further confirm the hepatoprotective effects of TCAs. In conclusion, our data show that TCAs, GleNAcCys particularly, have hepatoprotective anti antioxidant etfects.展开更多
This work aims to study the appropriate method for extract Betel leaf as crude extracts to prepare as a natural antioxidant in moisturizing hand cream. Betel leaf was treated by 7 methods and the optimized method was ...This work aims to study the appropriate method for extract Betel leaf as crude extracts to prepare as a natural antioxidant in moisturizing hand cream. Betel leaf was treated by 7 methods and the optimized method was selected for preparation of Betel leaf extract. The fresh Betel leaf and dried Betel leaf were used in this study. Betel leaf extracts were analysed for total phenolic content and essential oil as eugenol content. Then Betel leaf extracts were used as the one component for moisturizing hand cream. The lipid oxidation was evaluated by measurement on malondialdehyde content. The results revealed that an extracts solution from dried Betel leaf contained total phenolic content and eugenol content more than flesh Betel leaf. The ethanol extraction method was the optimum method since this method showed the maximum total phenolic content and eugenol content in dried Betel leaf as 5.26 g/100 g and 138.95 mg/100 g, respectively. The moisturizing creams were formulated by using crude Betel leaf extracts as the one composition compare with base cream (no addition of Betel leaf extracts). The moisturizing cream samples were analysed for malondialdehyde. its showed that the cream that contained Betel leaf extract contained malondialdehyde content lower than in cream base. Thus, crude extracts from Betel leaf showed the efficacy to reduce lipid oxidation reaction in moisturizing hand cream.展开更多
Hydrilla verticillata (I.f.) Royle twigs were exposed to CdCI2 (50, 100, 200 and 500 BM) under continuous light for 48 hrs and the physiological parameters like photosynthetic pigment (chlorophylls a, b and carot...Hydrilla verticillata (I.f.) Royle twigs were exposed to CdCI2 (50, 100, 200 and 500 BM) under continuous light for 48 hrs and the physiological parameters like photosynthetic pigment (chlorophylls a, b and carotenoids) contents, activities of antioxidative enzymes like superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) along with lipid peroxidation level were determined. With respect to increase in Cd concentration in the medium and exposure duration, decrease in pigment contents, and decrease in the activities of SOD, CAT and POX were found. The increased levels of lipid peroxidation indicated the prevalence of oxidative stress situation in the tissues which might be one of the reasons behind Cd induced toxicity in Hydrilla verticillata. Since there was significant decrease in the activities of key antioxidative ezymes, the study suggests that Hydrilla verticillata may not be effective for phytoremediation of cadmium in these concentration ranges.展开更多
Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic an...Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic and non-enzymatic) and lipid peroxidaton in liver and gill tissues of juvenile GIFT tilapia Oreochromis niloticus. After 8 days of exposure to Cd (0, 0.016, 0.08, 0.4 and 2 mg/L), livers accumulated significantly more Cd than gills. Catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were stimulated only at the highest concentration tested (2 mg/L). Glutathione peroxidase (GPx) activity was stimulated in the gill while inhibited in the liver, these alternations in gill and liver showed a strong relationship with Cd levels in these tissues. This may indicate either a tissue-specific response of GPx to Cd or, most probably, a hormetic effect of Cd on GPx. Cd increased GSH levels and decreased the ratio GSSG/GSH in fish livers at 2 mg/L. Cd exposure resulted in an elevated level of MDA in the livers of fish at 2 mg/L, indicating that Cd caused lipid peroxidation. Taken together, the results demonstrated that Cd altered the enzymatic and non-enzymatic defensive systems and caused lipid peroxidation in O. niloticus at relatively high concentrations (compared to environmentally relevant concentrations). In addition, the results implied that O. niloticus could tolerate high level of Cd in sites polluted by Cd.展开更多
文摘AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.
文摘Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their chemical properties and spectroscopic analyses, including extensive 2D NMR experiments. Compound 2 showed strong DNA cleavage activity, and compounds 1, 2 and 10 (2, 3, 4′, 5_tetrahydroxy_ trans _stilbene_2_O_β_ D _glucopyranoside) exhibited significant inhibition of lipid peroxidation.
文摘[ Objective] The aim of this study was to discuss the effect of antioxidants and lipid peroxidation from pea crops of plateau. [ Method] SOD enzyme liquid from pea crops of plateau was extracted by means of protein concentration assay, enzyme activity assay and antioxidant activity determination by DPPH method, peroxide activity inhibition of in vitro tissues from mice by homogenate MDA colorimetry method and lipid peroxidation assay of in vitro tissues. [ Result ] IC50 of the crude enzyme liquid extracted from pea on DPPH was 55.16 mg/L, while the scavenging rate of the crude enzyme liquid was lower than that of ascorbic acid, tea polyphenol and citric acid with the same concentration. The synergistic effect was found in ascorbic acid and crude enzyme liquid, but the synergism of ascorbic acid was better than that of citric acid. IC50 of SOD enzyme liquid extracted from pea on DPPH was 11.1 mg/L, which was better than that of tea polyphenol and closely similar to that of ascorbic acid. SOD enzyme liquid extracted from pea had an inhibitory effect on MDA production from in vitro tissues such as liver, kidney and heart, especially for a significantly inhibitory effect on MDA from liver in vitro. When the concentration was 0.25 mg/ml, the inhibition rate reached 78.3%, and then the inhibition rate increased little with the concentration incresas, while its effect on heart and kidney were inferior. [ Conclusion] SOD crude enzyme liquid and SOD enzyme liquid extracted from pea all have certain DPPH scavenging capacity, while SOD enzyme liquid extracted from pea has an inhibitory effect on lipid peroxidation.
文摘The inhibitory effect of the methanolic extract of the root of Aegle marmelos (MERA) and its constituents on the lipid peroxidation in vivo and in vitro were studied. The results suggested that MERA increased the activities of superoxide dismutase (SOD) and GSH-peroxidase in the liver cytosol of mice, but showed no significant effect on the activity of catalase, and one of its major constituents, 4-methoxy-1-methyl-2-quinolone (MMQ) increased the activity of SOD in liver tissue of mice intoxicated with FeCl2-ascorbic acid (AA)-ADP in vivo. Various constituents isolated from the root of title plant inhibited the lipid peroxidation in rat liver homogenate, which was in vitro induced by FeCl2-ascorbic acid, CCl4-NADPH, or ADP- NADPH. Of the test compounds, MMQ and its derivatives integriquinolone were similar to (-tocopherol in inhibiting MDA production in rat liver microsomes induced by Fe2+-ascorbate, CCl4-NADPH, or ADP-NADPH.
基金Supported by the China Postdoctoral Science Foundation and the National Natural Science Foundation of China, No. 90209046
文摘AIM: To investigate the anti-lipid peroxidation and protection of liver mitochondria against injuries in mice with liver damage by picroside Ⅱ. METHODS: Three animal models of liver damage induced by carbon tetrachloride (CCl4: 0.1 mL/10 g, ip), D-galactasamine (D-GaIN: 500 mg/kg, ip) and acetaminophen (AP: 0.15 g/kg, ip) were respectively treated with various concentrations of picroside Ⅱ (5, 10, 20 mg/kg, ig). Then we chose the continuously monitoring method (recommended by International Clinical Chemistry League) to analyze serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values, Marland method to detect the activity of manganese-superoxide dismutase (SOD) in liver mitochondria, TBA colorimetry to determine the content of malonicdialdehyde (MDA) in liver tissue, DTNB method to evaluate the activity of glutathioneperoxidase (GSH-Px) and Lowry method to detect protein level in liver tissue. Meanwhile, effects of picroside Ⅱ on the activity of ATPase and swelling extent of mitochondria in hepatocytes damaged by AP were also evaluated. RESULTS: Picroside Ⅱ could significantly prevent liver toxicity in the three models of liver damage. It decreased the high levels of ALT and AST in serum induced by the administration of CCl4, D-GaIN and AP, reduced the cellular damage of liver markedly, and appeared to be even more potent than the positive control drug of biphenyl dimethyl dicarboxylate pilules (DDB). In groups treated with different doses of picroside Ⅱ, compared to the model group, the content of MDA in serum decreased evidently, whereas the content of SOD and GSH-Px increased in a dose dependent manner, and the difference was statistically significant. Further, in the study of AP model, picroside Ⅱ inhibited AP-induced liver toxicity in mice, enhanced the activity of ATPase, improved the swelling extent of mitochondria and helped to maintain a normal balance of energy metabolism. CONCLUSION: Picroside II can evidently relieve hepatocyte injuries induced by CCI4, D-GaIN and AP, help scavenge free radicals, protect normal constructions of mitochondria membrane and enhance the activity of ATPase in mitochondria, thereby modulating the balance of liver energy metabolism, which might be part of the mechanisms of hepatoprotective effects of picroside Ⅱ.
文摘Antioxidants are used to minimize lipid oxidation. Antioxidants can act as metal chelators and free radical or oxygen scavengers, which can slow the progression of lipid oxidation. Lipid oxidation may have negative effects on the quality of meat and meat products, causing changes in sensory attributes such as color, texture, odor and flavor, and nutritional quality. Several synthetic antioxidants have been used to successfully prevent lipid oxidation in the meat industry, but consumers are concerned about the health risks related to consumption of some synthetic antioxidants. Therefore, there has been a growing interest in natural antioxidants. Nowadays, compounds obtained from natural sources such as grains, oilseeds, spices, fruit and vegetables have been investigated to decrease the lipid oxidation. In this review, the potential effects of natural antioxidants were evaluated that are widely used in meat and meat products.
文摘Objective: To estimate the oxidative stress and oxidative damage induced by abnormal free radical reactions in IgA nephropathy (IgAN) patients' bodies. Methods: Seventy-two IgA N patients (IgANP) and 72 healthy adult volunteers (HAV) were enrolled in a random control study design, in which the levels of nitric oxide (NO) in plasma, lipoperoxide (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and β-carotene (β-CAR) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric mothods. Results: Compared with the HAV group, the averages of NO in plasma, and LPO in plasma and in erythrocytes in the IgANP group were significantly increased (P<0.0001), while those ofVC, VE and β-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the IgANP group were significantly decreased (P<0.0001). Linear correlation analysis showed that with the increase of the values of NO, and LPO in plasma and in erythrocytes, and with the decrease of those ofVC, VE, β-CAR,SOD, CAT and GPX in the IgAN patients, the degree of histological damage of tubulointerstitial regions was increased gradually (P<0.0001); and that with the prolongation of the duration of disease the values of NO, and LPO in plasma and erythrocytes were increased gradually, while those of VC, VE, β-CAR, SOD, CAT and GPX were decreased gradually (P<0.005). The discriminatory correct rates of the above biochemical parameters reflecting oxidative damage of the IgAN patients were 73.8%-92.5%, and the correct rates for the HAV were 70.0%-91.3% when independent discriminant analysis was used; and the correct rate for the IgAN patients was increased to 98.8%, the correct rate for the HAV was increased to 100% when stepwise discriminant analysis was used. The above biochemical parameters' reliability coefficient (alpha) were used to estimate the oxidative damage of the IgAN patients as 0.8145, the standardized item alpha=0.9730, F=53273.5681, P<0.0001. Conclusions: A series of free radical chain reactions caused serious pathological aggravation in the IgANP' bodies, thus resulting in oxidative damage in their bodies. In treating IgANP, therefore, it is necessary that suitable dose antioxidants should be supplemented to them so as to alleviate the oxidative damage in their bodies.
基金financially supported by grant from the National Natural Science Foundation of China (No. 30972262)
文摘The aim of this study was to compare the effects of waterbome copper (Cu) and cadmium (Cd) on survival, anti-oxida- tive response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals (initial weight: 7.49 g±0.01 g) were exposed to graded concentrations of waterborne Cu (0.02, 0.04, 0.06, 0.08 mg L-1) or Cd (0.025, 0.05, 0.25, 0.5 mgL-1) for 28 days, respectively. Activities of the anti-oxidative enzymes (catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione (GSH) and malondiadehyde (MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L-1 and 0.08 mgL-1 Cu caused 100% death of abalone on the 21st, 10th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopan- creas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense against Cu or Cd. In conclusion, anti-oxidative mechanism in abalone to resist waterborne Cu did not follow the same pattern as that for waterborne Cd.
基金Supported by the National Natural Science Foundation of China(Nos.31072212,41076100)the CAS Scientific and Technological Innovation Program for Cross and Cooperative Team,Marine Economy Innovative Development Project(No.12PYY001SF08)the National Key Basic Program of Science and Technology Platforms of Aquaculture Stock Resources,Shandong Technology Development Project(No.2013GHY11509)
文摘The present study evaluated the ef fects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm motility and the activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GPx), glutathione reductase(Gr), and lipid peroxidation(measured via malondialdehyde(MDA) content) were determined after the milt was stored at 4°C for 12 h, cryopreserved without cryoprotectant in 12% propylene glycol(PG), cryopreserved in 12% PG+0.1 mol/L trehalose, or cryopreserved in 12% PG spermatozoa but centrifuged to decant the supernatant prior to cryopreservation(only sperm cells were cryopreserved). After chilled storage or cryopreservation, the SOD, CAT and GPx activities were reduced in sperm cells and increased in seminal plasma in almost all treatments; sperm motility parameters were also decreased. However, the addition of trehalose into the cryoprotectant could signifi cantly improve the postthaw sperm quality as revealed by the sperm average path velocity. This improvement might be attributed to the function of trehalose in scavenging reactive oxygen species. Chilled storage and cryopreservation had signifi cant eff ects on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod.
文摘The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxidation and development of off-flavor for over 50 years. However, the literature has expressed safety concerns and health risks (toxic and carcinogenic effects) associated with the use of synthetic antioxidants recently. Natural antioxidative substances from the polyphenols of edible plants are believed to be safer and may provide with additional health benefits and more effective compared to synthetic antioxidants. Due to the fact that natural antioxidants are additives that people mixed with food and consumed for centuries, they are known to be safe by the consumer. Therefore, it is an area worth to investigate due to consumer concerns about health. In the literature, there are many studies showing that the natural antioxidants have important antioxidant effect. Plants (oil seeds, cereals, vegetables, fruits, herb and spices), compounds from animal source (peptides and amino acids), enzymes and some microorganisms are important natural antioxidants. Plant extracts have been widely used to retard lipid oxidation in foods during frying and accelerated storage processes. They were found as strong antioxidant sources due to their high contents of phenolic compounds. There are countless studies about natural antioxidants. However, they have not been investigated completely by means of toxicology.
基金Supported by Research Grant From the Polish State Committee for Scientific Research 3 PO5B 07922
文摘AIM: Reactive oxygen species (ROS) can induce carcinogenesis via DNA injury. Both enzymatic and non-enzymatic parameters participate in cell protection against harmful influence of oxidative stress. The aim of the present study was to assess the levels of final lipid peroxidation products like malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE) in primary colorectal cancer. Moreover, we analysed the activity of main antioxidative enzymes, superoxide dismutase (Cu, Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GSSRG-R) and the level of non-enzymatic antioxidants (glutathione, vitamins C and E). METHODS: Investigations were conducted in 81 primary colorectal cancers. As a control, the same amount of sample was collected from macroscopically unchanged colon regions of the most distant location to the cancer. Homogenisation of specimens provided 10% homogenates for our evaluations. Activity of antioxidant enzymes and level of glutathione were determined by spectrophotometry. HPLC revealed levels of vitamins C and E and served as a method to detect terminal products of lipid peroxidation in colorectal cancer. RESULTS: Our studies demonstrated a statistically significant increase in the level of lipid peroxidation products (MDA-Adc. muc.-2.65±0.48 nmol/g, Adc.G3-2.15±0.44 nmol/g, clinical IV stage 4.04±0.47 nmol/g, P<0.001 and 4-HNE-Adc.muc. -0.44±0.07 nmol/g, Adc.G3-0.44±0.10 nmol/g, clinical IV stage 0.52±0.11 nmol/g, P<0.001) as well as increase of Cu,Zn-SOD (Adc.muc.-363±72 U/g, Adc.G3-318?8 U/g, clinical IV stage 421±58 U/g, P<0.001), GSH-Px (Adc.muc. -2143±623 U/g, Adc.G3-2005±591 U/g, clinical IV stage 2467±368 U/g, P<0.001) and GSSG-R (Adc.muc.-880±194 U/g, Adc.G3-795±228 U/g, dinical IV stage 951±243 U/g, P<0.001) in primary tumour comparison with normal colon (MDA-1.39±0.15 nmol/g, HNE-0.29±0.03 nmol/g, Cu, Zn-SOD-117±25 U/g, GSH-Px-1723±189 U/g, GSSG-R-625±112 U/g) especially in mucinous and G3-grade adenocarcinomas as well as clinical IV stage of colorectal cancer. We also observed a decrease of CAT activity (Adc.muc. -40±14 U/g, clinical IV stage 33±18 U/g vs 84±17 U/g, P<0.001) as well as a decreased level of reduced glutathione (clinical IV stage 150±48 nmol/g vs 167±15 nmol/g, P<0.05) and vitamins C and E (vit. C-clinical IV stage 325±92 nmol/g vs 513?4 nmol/g, P<0.001; vit. E-clinical IV stage 13.3±10.3 nmol/g vs 37.5±5.2 nmol/g). CONCLUSION: Colorectal carcinogenesis is associated with serious oxidative stress and confirms that gradual advancement of oxidative-antioxidative disorders is followed by progression of colorectal cancer.
文摘The antioxidant activities of the ethyl acetate fraction and aqueous extract of unripe fruit of Carica papaya were compared and investigated in vitro using thiobarbituric reactive species (TBARS) assay, total phenol content, evaluation of reactive oxygen species (ROS) in liver mitochondria, Fe2+ chelating and 2,2-diphenyl-lpicrylhydrazyl (DPPH) scavenging activities. Both extracts had high antioxidant properties and could inhibit FeE+ and sodium nitroprusside lipid peroxidation in the liver. Total phenol content of ethyl acetate fraction and aqueous extract were 4.50 ±2.26 and 1.21±3.12 mg/g, respectively. Both extracts had a maximal effect at the lowest concentrations tested (15 μg/mL for ethyl acetate and 150 μg/mL for the aqueous). Ethyl acetate fraction showed that the highest values of antioxidant activity is probably associated with its high phenolic content, Fe2+ chelating and DPPH scavenging activities. It is therefore concluded that ethyl acetate fraction and to a less extent the aqueous fractions are potent inhibitor of lipid peroxidation.
文摘Germinating wheat (Triticum aestivum L.) seeds were exposed to CdCI2 (50, 100 and 200 μM) for 48 h and some aspects of oxidative metabolism was assessed in the embryonic tissues. The germination percentage and the soluble protein content of the embryonic tissues were found to decrease with increasing of Cd concentration. There was elevation in superoxide dismutase (SOD) and decline in catalase (CAT) and peroxidase (POX) activities. The increasing of lipid peroxidation levels indicated the prevalence of oxidative stress in the tissues which was probably due to the alteration of antioxidative enzymes activities. The adding of ascorbate, along with CdCl2, has resulted in restoration of the Cd induced decline in CAT activity. Weakening in H2O2 detoxification system seems to be the principal reason behind Cd induced oxidative stress in germinating seeds. Thus, imposition of oxidative stress might be the consequence of cadmium stress and this finding may help in elucidating the mechanisms underlying cadmium mediated toxicity in germinating seeds.
基金Supported by the China Postdoctoral Science Foundation(No.2013M531648)the Natural Science Foundation of Shandong Province(No.ZR2014DP008)+2 种基金the Fundamental Research Funds for the Central Universities(No.201513046)the National Special Research Fund for Non-Profit Marine Sector(No.201305009)the Joint Funds of the National Natural Science Foundation of China(No.U1406403)
文摘Green tides have occurred every year from 2007 to 2014 in the Yellow Sea. Ulva prolifera (Mtiller) J. Agardh has been identified as the bloom-forming alga, co-occurring with U. intestinalis. We observed distinct strategies for both algal species during green tides. U.prolifera exhibited a high abundance initially and then decreased dramatically, while U. intestinalis persisted throughout. The antioxidant system responses of these two macroalgae were compared in the late phase of a green tide (in-situ) and after laboratory acclimation. Lipid peroxidation and antioxidant system responses differed significantly between the two. Malondialdehyde and hydrogen peroxide contents increased significantly in-situ in U. prolifera, but not in U. intestinalis. In U. prolifera, we observed a significant decrease in total antioxidant ability (T-AOC), antioxidant enzymes (SOD and Apx), and non-enzyme antioxidants (GSH and AsA) in-situ. U. intestinalis showed the same pattern of T-AOC and SOD, but its Gpx, Apx, and GSH responses did not differ significantly. The results suggest that U. prolifera was more susceptible than U. intestinalis to the harsh environmental changes during the late phase of a Yellow Sea green tide. The boom and bust strategy exhibited by U. prolifera and the persistence of U. intestinalis can be explained by differences in enzyme activity and antioxidant systems.
文摘This study aimed to purify and determine antioxidant activities of different fractions obtained during the purification process of phycocyanin from Spirulina platensis. The dried powder of Spirulina platensis, after ground with sands, was extracted with 50 mM sodium phosphate buffer at pH 6.8 before centrifuged to precipitate unwanted proteins. Then the supernatant was separated by celit column to obtain semi-pure phycocyanin and further purified by treated with ammonium sulfate. The purity of phycocyanin was monitored by measuring the absorbance spectrum from 200 to 700 nm. Its purity ratio A620A280 was determined. The antioxidant activities of the obtained phycocyanin were determined by 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) assay and lipid peroxidation (linoleie acid) assay. The purity ratio of phycocyanin in the Spirulina crude extract was 0.36 and increased to 2.68 after purification. The fraction with the highest purity ratio of phycocyanin demonstrated the hightest antioxidant activities. For ABTS assay, it presented the Vitamin C Equivalent Antioxidant Capacity (VCEAC) value of 0.0405 ±0.0002 mg of ascorbic acid/mg of sample and the Trolox Equivalent Antioxidant Capacity (TEAC) value of 0.0485 ±0.0002 mg oftrolox/mg of sample respectively. The result from lipid peroxidation assay exhibited IC50 value of 5.9336 ±0.2565 mg/mL. The purification of Spirulinaplatensis crude extract obtained from this study increased the purity ratio of phycocyanin and its antioxidant activities. This will be further investigated for the development into anti-aging cosmetic products.
文摘Two new 2-substituted thiazolidine-4(R)-carboxylic acids (TCAs), 2-glusosaminal-TCA (GIcNH2Cys) and 2-N-acetyl-glueosanlinal-TCA (GlcNAeCys), were synthesized. Their protective effects against liver toxicity induced by acetaminophen (APAP) were investigated in a mice model. The resuits demonstrate that administration of TCAs ( i. p. , 800 mg/kg) 30 min after APAP challenge efficiently decrease ALF, AST, and LDH levels in liver. GlcNAcCys shows the best proteetive eftects, decreasing ALT, AST and LDH levels to 63%, 18.4% and 37% of the APAP group respectively. Comparison with the control showed that APAP greatly decreases total sulfhydlyl (T-SH) levels (43%), non-protein hound sulfhydryl (NP-SH) levels (50%) and total antioxidative capabilities (57%) in the liver 24 hr after challenge. TCAs treatments 30min after APAP challenge significantly elevate sulfhydryl levels and total antioxidative capabilities. APAP administration also markedly (P 〈 0.05) increases liver lipid peroxidation to 1.65 and 1.17 times that of the control 4 hr and 24 hr after APAP administration respectively. TCAs treatments can inhibit lipid peroxidation as measured by decreased malondialdehyde (MDA) contents in liver. The histopathological results also further confirm the hepatoprotective effects of TCAs. In conclusion, our data show that TCAs, GleNAcCys particularly, have hepatoprotective anti antioxidant etfects.
文摘This work aims to study the appropriate method for extract Betel leaf as crude extracts to prepare as a natural antioxidant in moisturizing hand cream. Betel leaf was treated by 7 methods and the optimized method was selected for preparation of Betel leaf extract. The fresh Betel leaf and dried Betel leaf were used in this study. Betel leaf extracts were analysed for total phenolic content and essential oil as eugenol content. Then Betel leaf extracts were used as the one component for moisturizing hand cream. The lipid oxidation was evaluated by measurement on malondialdehyde content. The results revealed that an extracts solution from dried Betel leaf contained total phenolic content and eugenol content more than flesh Betel leaf. The ethanol extraction method was the optimum method since this method showed the maximum total phenolic content and eugenol content in dried Betel leaf as 5.26 g/100 g and 138.95 mg/100 g, respectively. The moisturizing creams were formulated by using crude Betel leaf extracts as the one composition compare with base cream (no addition of Betel leaf extracts). The moisturizing cream samples were analysed for malondialdehyde. its showed that the cream that contained Betel leaf extract contained malondialdehyde content lower than in cream base. Thus, crude extracts from Betel leaf showed the efficacy to reduce lipid oxidation reaction in moisturizing hand cream.
文摘Hydrilla verticillata (I.f.) Royle twigs were exposed to CdCI2 (50, 100, 200 and 500 BM) under continuous light for 48 hrs and the physiological parameters like photosynthetic pigment (chlorophylls a, b and carotenoids) contents, activities of antioxidative enzymes like superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) along with lipid peroxidation level were determined. With respect to increase in Cd concentration in the medium and exposure duration, decrease in pigment contents, and decrease in the activities of SOD, CAT and POX were found. The increased levels of lipid peroxidation indicated the prevalence of oxidative stress situation in the tissues which might be one of the reasons behind Cd induced toxicity in Hydrilla verticillata. Since there was significant decrease in the activities of key antioxidative ezymes, the study suggests that Hydrilla verticillata may not be effective for phytoremediation of cadmium in these concentration ranges.
文摘Heavy metals pose a potential threat to aquatic organisms. In this study, a static-renewal acute toxicity test was conducted to investigate the effects of cadmium on the antioxidant defense systems (both enzymatic and non-enzymatic) and lipid peroxidaton in liver and gill tissues of juvenile GIFT tilapia Oreochromis niloticus. After 8 days of exposure to Cd (0, 0.016, 0.08, 0.4 and 2 mg/L), livers accumulated significantly more Cd than gills. Catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were stimulated only at the highest concentration tested (2 mg/L). Glutathione peroxidase (GPx) activity was stimulated in the gill while inhibited in the liver, these alternations in gill and liver showed a strong relationship with Cd levels in these tissues. This may indicate either a tissue-specific response of GPx to Cd or, most probably, a hormetic effect of Cd on GPx. Cd increased GSH levels and decreased the ratio GSSG/GSH in fish livers at 2 mg/L. Cd exposure resulted in an elevated level of MDA in the livers of fish at 2 mg/L, indicating that Cd caused lipid peroxidation. Taken together, the results demonstrated that Cd altered the enzymatic and non-enzymatic defensive systems and caused lipid peroxidation in O. niloticus at relatively high concentrations (compared to environmentally relevant concentrations). In addition, the results implied that O. niloticus could tolerate high level of Cd in sites polluted by Cd.