A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity

In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.

Alkaline sphingomyelinase deficiency impairs intestinal mucosal barrier integrity and reduces antioxidant capacity in dextran sulfate sodium-induced colitis

BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway.

Patients with primary biliary cirrhosis have increased serum total antioxidant capacity measured with the crocin bleaching assay

AIM： The balance between oxidants and antioxidants can play an important role in the initiation and development of liver diseases. Recently, we have described a new automated method for the determination of total antioxidant capacity （TAC） in human serum and plasma.METHODS： We measured TAC and corrected TAC （CTACabstraction of interactions due to endogenous uric acid,bilirubin and albumin） in 52 patients with chronic liver diseases （41 patients with primary biliary cirrhosis （PBC）,10 patients with chronic hepatitis C and 13 patients with viral HCV cirrhosis） as well as in 10 healthy controls. In 23 PBC patients measurement were also done 6 mo after treatment with ursodeoxycholic acid （UDCA）. The TAC assay was based on a modification of the crocin bleaching assay. The results were correlated with routine laboratory measurements and the histological stage of PBC.RESULTS： There were no significant differences in TAC between the various groups. However, CTAC was considerably increased in the PBC group compared to controls and cirrhotics. Analysis of these patients according to disease stages showed that this increase was an early phenomenon observed only in stages I and II compared to controls, cirrhotics and patients with chronic hepatitis C）.After 6 mo of treatment with UDCA, levels of CTAC decreased to those similar to that of controls.CONCLUSION： Patients in the early stages of PBC present with high levels of corrected total antioxidant capacity and this maybe related to the pathophysiology of the disease. UDCA treatment restores the levels of CTAC to control levels.

Changes of total antioxidant capacity and total oxidant status of aqueous humor in diabetes patients and correlations with diabetic retinopathy

AIM:To measure changes of total oxidant status(TOS)and total antioxidant capacity(TAC) of aqueous humor(AH) in diabetic retinopathy(DR) patients,and to determine if there were any differences in TOS and TAC of AH in diabetic patients without retinopathy compared with non-diabetic patients.·METHODS:One hundred and three eyes of 103patients who were enrolled for cataract surgery were included in this study.Patients were grouped according to presence of diabetes and stage of DR.Prior to cataract surgery,0.1mL to 0.2mL of AH was aspirated and analyzed for TAC and TOS level using a colorimetric method.·RESULTS:TOS levels were highest among proliferative diabetic retinopathy(PDR) patients and lowest in patients with only cataracts.Results were statistically significant between all groups(P 【0.05).Whereas result between diabetic without retinopathy patients and non-proliferative diabetic retinopathy(NPDR) patients was not statistically significant(P =0.757).TAC levels were highest in patients with only cataract and lowest among PDR patients and results were statistically significant between all groups(P 【0.05).·CONCLUSION:Aqueous humor TAC levels are low in diabetic patients and reduced further in DR patients,TOS levels are increased in diabetic patients and this is exacerbated in DR patients.

The effect of fitness level on cardiac autonomic regulation, IL-6,total antioxidant capacity, and muscle damage responses to a single bout of high-intensity interval training

Purpose:The aim of this study was to investigate the influence of the cardiorespiratory fitness level on the response to high-intensity interval training(HIIT)with an individually adjusted running speed of the same relative intensity.The evaluation focused on acute cardiorespiratory response,postexercise cardiac autonomic modulation(heart rate variability(HRV))and biochemical markers of inflammation,oxidative stress,and muscle damage.Methods:Thirty participants were divided into 3 subgroups:well trained,moderately trained,and untrained.All the participants performed30 min HIIT composed of 6×2 min interval exercise with work-to-relief ratio=1 and work intensity 100%of individual velocity at maximal oxygen consumption(VO2max).Acute cardiorespiratory variables,postexercise HRV,lactate,interleukin-6(IL-6),total antioxidant capacity(TAC),creatine kinase,and myoglobin up to 4h after HIIT were monitored.Results:The differences in relatively expressed cardiorespiratory variables(heart rate,VO2)during HIIT were at most moderate,with the most pronounced between-group differences in absolute VO2 values.The disruption of the postexercise HRV was the most pronounced in untrained individuals,and this difference persisted 1 h after HIIT.The highest postexercise IL-6 and TAC concentrations and the lowest changes in creatine kinase and myoglobin were revealed in well-trained individuals.Conclusion:The higher fitness level was associated with the less pronounced postexercise cardiac autonomic changes and their faster restoration,even when there were similar acute cardiorespiratory responses.These findings were simultaneously accompanied by the higher postexercise IL-6 and TAC concentrations and less significant changes in muscle damage biochemical markers in well-trained individuals.

Total soy saponins improve the antioxidant capacity of the myocardium and exercise ability in exhausted rats

Purpose：The aim of the present study was to investigate the impact of total soy saponins（TS） on the myocardial antioxidant capacity in rats exercised to exhaustion.Methods：The one-time exhausted treadmill model was used.All rats were divided into 4 groups：the control group,the TS group,the exhausted group,and the TS exhausted group.The TS and TS exhausted groups were fed TS at a dosage of 20 mg/kg body weight,once a day,for 2 weeks.The exhausted group was given a placebo,and the control group was not given any treatment.The treadmill speed was set at 30 m/min,and the rats（exhausted and TS exhausted groups） were trained at this speed until exhausted.The rats were decapitated and anatomized immediately after exhausted.A 10% homogenate of the myocardial tissue was prepared.Results：TS significant y increased the exercise time by 20.62%（p〈0.05）.As compared with the control group,the enzyme activities for catalase（CAT）,glutathione peroxidase（GSH-Px）,and glutathione reductase（GR） were significant y enhanced in the TS group（p〈0.01）;GR and GSH-Px activity was significant y enhanced in the TS exhausted group（p〈0.01）;malondialdehyde（MDA） levels were significant y decreased in the TS exhausted group（p〈0.05）.As compared with the exhausted group,the GSH-Px activity was significant y enhanced in the TS exhausted group（p〈0.01）;CAT,GSH-Px,and GR activities were significant y enhanced in the TS group（p〈0.01）.As compared with the TS group,the CAT and GR activity in the TS exhausted group was significant y decreased（p〈0.01）.Conclusion：TS can improve the exercised rats＇ antioxidant activity in their cardiac muscle to varying degrees,decrease MDA and serum AST and LDH levels,increase the exercise time,and delay the occurrence of sports fatigue.

Total Flavonoid Content, the Antioxidant Capacity, Fingerprinting and Quantitative Analysis of Fupenzi (<i>Rubus chingii</i>Hu.)

Objective: In this study, one of the objectives was to investigate the total flavonoid contents of Fupenzi (R. chingii Hu.) obtained from different regions of China and to evaluate their anatioxidant activities. And the second objective of this study was to develop a validated HPLC method for chromatographic fingerprints of the samples extracts of Fupenzi. Method: The total flavonoid contents were determined by a colorimetric method and the antioxidant activity was determined spectrophotometrically by DPPH and ABTS radical scavenging assays. The chromatographic fingerprint was developed by high-performance liquid chromatography coupled with diode array detection for the control of Fupenzi. Results: A significant correlation between antioxidant activity and the total flavonoid content was observed for the DPPH assay (r2 = 0.758, ρ = 0.004) and the ABTS assay (r2 = 0.788, ρ = 0.002). Under the optimized chromatographic conditions, the validated method was successfully applied to assessment of chemical fingerprinting of 12 batches of FPZ collected from different regions of China. Comparisons of the chromatograms showed that 15 characteristic peaks could be selected as markers for identification and evaluation of Fupenzi. In addition, the proposed method was also successfully applied to simultaneous determination of five compounds (including puerarin, rutin, hyperin, quercetin and kaempferol) in these samples. Conclusions: The qualitative and quantitative analysis described in this paper could be used for identification and evaluation of Fupenzi.

Antioxidant Capacity and Total Phenol Content of Commonly Consumed Indigenous Foods of Asian Tropical Regions

In order to screen the antioxidant capacity of commonly consumed indigenous foods of tropical region, vegetables, fruits, tea, oil seeds, legumes, spices and cereal were analyzed. Among the vegetables, green chili showed the highest total oxygen radical absorbance capacity （ORACFL） and lipophilic ORAC （L-ORACFL）; whereas, bean showed highest hydrophilic ORAC （H-ORACFL） content. The H-ORACFL of vegetable samples varied between 2.26 to 23.08 ~tmol of Trolox equivalent （TE）/g of fresh weight （FW） and L-ORACFL content widely varied from 0.20 （sweet pumpkin） to 16.95 （green chili）. The range of H-ORACFL values of fruits showed large variation （0.45-178 Ixmol of TE/g FW）. All four different types of tea showed high H-ORACFL （1,295.84-2,709.11 lamol of TE/g）, in contrast to negligible amount of L-ORACFL. In legumes, H-ORACFL content ranged from 16.22 to 140.54; whereas, L-ORACFL ranged from 4.43 to 25.78. Porso millets showed higher L-ORACFL value （19.4） as compared to H-ORACFL （0.8）. In case of spices, L-ORACFL content varied from 29.75 ± 0.00 to 1,575.24 ± 39.63, which is considerably higher as compared to H-ORACFL （61.68 ± 1.71 to 272.82± 1.05） content. Comparatively, spices showed much higher H-ORACFL values as compared to fruits analyzed. In case of selective vegetables, fruits and tea samples, the total phenol content was highly correlated with the H-ORACFL content.

A Novel Assay for Measuring Total Antioxidant Capacity in Whole Blood and Other Biological Samples

A new method for rapidly determining total antioxidant capacity (TAC) in a biological sample has been devised and evaluated. A surfactant present in the reagent causes the lysis of cells in the sample. Glutathione, ascorbic acid, protein thiols and other main reducing substances in the sample react with a specific redox chromogen (2,6-dichlorophenolindophenol) and produce a change in the color of the reagent, which is determined photometrically at 630 nm. This new method quantifies the overall capacity of the sample to reduce a redox chromogen and it requires the minimum volumes and time. The assay can be used on a wide variety of biological samples including whole blood, serum, plasma, tissue extracts and homogenates, food, wine, fruit juice and other beverages. Results are expressed in terms of mmol/L glutathione equivalents. TAC can be assayed manually, on automatic analyzers or micro-plate readers.

Variability in total antioxidant capacity, antioxidant leaf pigments and foliage yield of vegetable amaranth

Twenty vegetable amaranth genotypes were evaluated for total antioxidant capacity, antioxidant leaf pigments, vitamins, and selection of suitable genotypes for extraction of juice in a randomized complete block design（RCBD） with three replications. Vegetable amaranth was rich in chlorophyll, β-cyanins, β-xanthins, betalains, carotene, ascorbic acid and total antioxidant. The genotypes VA14, VA16, VA18, VA15, and VA20 could be selected as amaranth vegtable varieties with high yields and abundance antioxidant leaf pigments and vitamins to produce juice. The genotypes VA13 and VA19 had above-average foliage yield and high antioxidant profiles while the genotypes VA2, VA3, VA9, VA11, VA12, and VA17 had a high antioxidant profiles and below-average foliage yield. These genotypes could be used as a donor parent for integration of potential high antioxidant profiles genes into other genotypes. The correlation study revealed a strong positive association among all the antioxidant leaf pigments, total antioxidant capacity and foliage yield. Selection based on total antioxidant capacity, antioxidant leaf pigments could economically viable to improve the yield potential of vegetable amaranth genotypes. Total carotene and ascorbic acid exhibited insignificant genotypic correlation with all the traits except total antioxidant capacity. This indicates that selection for antioxidant vitamins might be possible without compromising yield loss.

Effect of Chromium on Oxidative Damage and Antioxidant Capacity of Ctenopharyngodon idellus

[Objective] This study aimed to investigate the effect of chromium on ox- idative damage and antioxidant capacity of Ctenopharyngodon idellus （grass carp）. [Method] The grass carps were treated with hexavalent chromium （Cr^6＋） solution at concentrations of 0, 7.23, 14.47, 28.94 mg/L, and then the content of malondialde- hyde （MDA）, the level of total antioxidative capacity （T-AOC） and the activity of gtu- tathione-S-transferase （GST） in the hepatopancreas of grass carp were determined after 96 hours in different treatment groups. [Result] The content of MDA presented increasing trend with the increase of exposure Cr^6＋ concentrations. The activity of T-AOC increased firstly, then decreased with the increasing Cr^6＋ exposure concentra- tions, showing that the level of T-AOC was induced in tow and medium concentrat ions （7.23 and 14.47 mg/L）, but inhibited in high concentrations （28.94 mg/L）. Among the exposure groups, the level of T-AOC in medium concentration group （14.47 mg/L） was significantly higher than the control （P〈0.05）. Except the low concentration groups （7.23 mg/L） of which the GST activity was slightly induced, the GST activities of the other groups all showed downward trend with increasing Cr^6＋ levels, and the activity of GST in 28.94 mg/L group was significantly lower than the control group （P〈0.05）. [Conclusion] Cr^6＋ could cause large oxidative damage in the hepatopancreas of grass carp, thus poisoning it, and Cr^6＋ may further damage the organizational structure and physiological function of grass carp.

The Role of C-Reactive Protein, Granulocyte Colony Stimulating Factor and Total Antioxidant Capacity in Diagnosis of Acute Appendicitis

Background and Aim: Despite the fact that acute appendicitis is the most common surgical emergency all around the world, its diagnosis is still based on clinical evaluation and accuracy of the diagnosis depending on experience. The aim of this study is to evaluate the role of inflammatory markers in diagnosis of acute appendicitis. Material and Method: The study includes 77 cases with histopathologically proven acute appendicitis and 17 control cases. Blood samples were obtained from all cases and C-reactive protein (CRP), Granulocyte Colony Stimulating Factor (G-CSF) and Total Antioxidant Capacity (TAC) were measured. Findings: In cases with acute appendicitis, CRP and G-CSF levels were found to be related to acute appendicitis;however, TAC was not affected by the disease process. Moreover, CRP and G-CSF levels were correlated with the disease severity. Conclusion: Both CRP and G-CSF can be used in diagnosis of acute appendicitis. Furthermore, increased CRP level can be a marker to show advanced cases. However, G-CSF is not an effective marker to show disease severity.

Effect of Colchicine on Total Antioxidant Capacity,Antioxidant Enzymes and Oxidative Stress Markers in Patients with Knee Osteoarthritis

Background/Aim: We aimed to investigate the effects of colchicine on clinical recovery, as well as oxidative stress markers and total antioxidant capacity (TAC) in whole blood of patients with knee osteoarthritis (OA). Materials and methods: Sixty patients with grade 2 - 3 knee OA according to ACR knee OA criteria whom examination of the knee joint synovial fluid by polarized light microscopy demonstrated CPDD crystals existence were included in the study. Fifty healthy subjects were included as a control group. Patients were divided randomly into two groups. The first group (paracetamol group) was given only paracetamol 3 gr daily p.o and the second group (colchicine and paracetamol group) was given colchicine 1,5 gr and paracetamol 3 gr daily p.o for six months. For outcome measures WOMAC and VAS were used. Superoxide dismutase (SOD), Catalase (CAT) ezyme activities and Glutathione (GSH) and Malondialdehyde (MDA) levels and TAC all were measured. Results: WOMAC scores were improved in both patient groups compared with pre-treatment evaluation (p 0.05). TAC was signifcantly increased only in colchicine/paracetamol group. Oxidant parameter MDA levels were significantly decreased in both paracetamol group and colchicine/paracetamol group. CAT, SOD enzyme activities and GSH levels did not change before and after treatment protocols in both patient groups. Conclusion: Both paracetamol 3000 mg/day and 3000 mg paracetamol plus 1,5 gr/day colchicine is effective in the treatment of patients with knee osteoarthritis. But the addition of colchicine to paracetamol produced significantly greater symptomatic benefit than paracetamol alone. Our study also showed that colchicine lowers whole blood MDA which is a lipid peroxidation compound and elevates TAC levels in patients with knee OA. This may show probable disease modifying effect of colchicine in knee OA which require further long period laboratory and radiologic investigations.

Selenium Differentially Regulates Flavonoid Accumulation and Antioxidant Capacities in Sprouts of Twenty Diverse Mungbean(Vigna radiata(L.)Wilczek)Genotypes

Seed germination with selenium(Se)is promising for producing Se-biofortified foods.Mungbean(Vigna radiata(L.)Wilczek)sprout is freshly eaten as a salad dressed with sauce,making it superior for Se biofortification.Since the Se safety range for the human body is extremely narrow,it is imperative to evaluate the genotypic responses of mungbean sprouts to Se.This study evaluated the Se enrichment capacity and interaction withflavonoids and antioxidant systems in sprouts of 20 mungbean germplasms.Selenium treatment was done by immersing mung-bean seeds in 20μM sodium selenite solution for 8 h.Afterward,the biomass,Se amounts,flavonoid(particularly vitexin and isovitexin)contents,antioxidant capacity,and key biosynthetic gene expressions were measured.Sprout Se content was 2.0-7.0μg g^(-1) DW among the 20 mungbean germplasms.Selenium treatment differentially affected the biomass,totalflavonoid,vitexin,isovitexin,antioxidant enzyme activities,and antioxidant capacities of the mungbean germplasms.Eight germplasms showed increased biomass(p<0.05),the highest increasing by 127%,but 13 did not phenotypically respond to Se treatment.Seven and six germplasms showed varied levels of vitexin and isovitexin increment after Se treatment,the highest measuring 2.67-and 2.87-folds for vitexin and isovitexin,respectively.Two mungbeanflavonoid biosynthesis genes,chalcone synthase(VrCHS)and chalcone isomerase(VrCHI)were significantly up-regulated in the germplasms with increased vitexin and isovitexin levels(p<0.05).Moreover,Se enrichment capacity was significantly correlated with the vitexin,isovitexin,and antiox-idant capacities.In conclusion,mungbean sprouts could be a useful Se-biofortified food,but the Se enrichment capacity and nutritional response must be determined for each germplasm before commercialization.

Quantification of Total Phenols, Total Flavonoids, Total Anthocyanins and Evaluation of Antioxidant and Antiradical Activities of Detarium Senegalense Extracts from Chad

The aim of the present work is to assess the value of Detarium Senegalense by determining the content of total phenols, total flavonoids and total anthocyanins, and by evaluating the free radical scavenging activity of Detarium Senegalense extracts. For this purpose, sequential extraction using solvents of increasing polarity was essential. The various extracts obtained underwent phytochemical and biochemical analyses. Phytochemical screening revealed the presence of flavonoids, alkaloids, tannins, polyphenols, anthocyanins and steroids/terpenes. Quantitative analysis of total polyphenols, total flavonoids and total anthocyanins yielded the following results: total flavonoids (0.803 ± 0029 mg EQ/100g P for acetone extract of roots and 0.871 ± 0.401 mg EQ/100g P for methanol extract of leaves);total polyphenols (23.298 ± 12.68 mg EAG/100g P for acetone extract of roots and 24.69 ± 0.49 401 mg EAG/100g P for methanol extract of leaves);total monomeric anthocyanins (44.697 ± 0.939 mg EC3G/100g P and 16.699 ± 0.193 mg EC3G/100g P respectively for acetone and methanol extracts of stem bark). DPPH free radical scavenging activity was 1.674 ± 0.023 mg/mL for the acetone extract and 0.934 ± 0.24 mg/mL for the methanol extract of roots. .

Phenolic and flavonoid contents of mandarin (Citrus reticulata Blanco) fruit tissues and their antioxidant capacity as evaluated by DPPH and ABTS methods

The total phenolic and flavonoid contents in the fruit tissues （peels, pulp residues, seeds, and juices） of 19 citrus genotypes belonged to Citrus reticulata Blanco were evaluated and their antioxidant capacity was tested by 2,2-diphenyl-l-picrylhydra- zyl radicals （DPPH） method and 2,2＇-azino-bis（3-ethylbenzthiozoline-6）-sulphonic acid （ABTS） method. The total phenolic and flavonoid contents, and their antioxidant capacity varied in different citrus fruit tissues. Generally, the peel had both the highest average of total phenolics （27.18 mg gallic acid equivalent （GAE） g^-1 DW） and total flavonoids （38.97 mg rutin equivalent （RE） g^-1 DW）. The highest antioxidant capacity was also the average of DPPH value （21.92 mg vitamin C equiv- alent antioxidant capacity （VCEAC） g^-1 DW） and average of ABTS value （78.70 mg VCEAC g-1 DW） in peel. The correlation coefficient between the total phenolics and their antioxidant capacity of different citrus fruits tissues ranged from 0.079 to 0.792, and from -0.150 to 0.664 for the total flavonoids. The antioxidant capacity of fruit tissues were correlated with the total phenoilc content and flavonoid content except in case of the peel. In addition, the total phenolic content and antioxidant capacity varied in different citrus genotypes. Manju and Karamandarin were better genotypes with higher antioxidation and the phenolic content, however Shagan was the poorest genotype with lower antioxidation and the phenolic content.

Effects of Cooking on Anthocyanin Concentration and Bioactive Antioxidant Capacity in Glutinous and Non-Glutinous Purple Rice

Purple rice is a source of bioactive antioxidants for rice consumers. Loss of the major antioxidant compounds after a range of cooking processes was evaluated by measuring the changes in anthocyanin concentration （ATC） and antioxidant capacity （DPPH activity） of four non-glutinous and four glutinous genotypes. However, soaking in water prior to cooking generally decreased more ATC and antioxidant capacity in non-glutinous than in glutinous genotypes. Wet cooking （WC） and soaking before wet cooking （S-WC） led to lose almost all the ATC and antioxidant capacity with only slight variation between genotypes. In the glutinous genotype Pieisu, which had the highest raw rice ATC, ATC remained the highest when cooked by the WC method. By contrast, almost no ATC remained after WC and S-WC in the low ATC genotypes such as Kum Doi Saket. Overall, the loss of ATC was greater in non-glutinous than in glutinous genotypes for both WC and S-WC methods, but the reverse occurred for antioxidant capacity. WC using electric rice cooker retained higher ATC than the pressure cooking. Thus, for genotypes with high ATC and antioxidant capacity, the selection of cooking method is critical for retaining and stabilizing rice quality.

Exogenous Hydrogen Sulfide Enhanced Antioxidant Capacity, Amylase Activities and Salt Tolerance of Cucumber Hypocotyls and Radicles

In the present experiment, effects of sodium hydrosulfide （NariS）, a H2S donor, on the oxidative damage, antioxidant capacity and the growth of cucumber hypocotyls and radicles were studied under 100 mmol L^-1 NaCl stress. NaCl treatment significantly induced accumulation of H2O2 and thiobarbituric acid-reactive substances （TBARS） in cucumber hypocotyls and radicles, and application of NariS dramatically reduced the accumulation of H/O2 and lipid peroxidation. However, the alleviating effects greatly depended on the concentrations of NariS, and 400 ~tmol L-1 NariS treatment showed the most significant effects. Corresponding to the change of lipid peroxidation, higher activities of antioxidant enzymes as well as the antioxidant capacity indicated as DPPH scavenging ac＇tivity, chelating activity of ferrous ions and hydroxyl radical （.OH） scavenging activity were induced by Naris treatment under NaCI stress, especially by 400 Ixmol L-I Naris treatment. With the alleviating lipid peroxidation, the amylase activities in cotyledons were increased, and the length of cucumber hypocotyls and radicles were significantly promoted by NariS treatment under NaCI stress. Unlike the effects of NariS, pretreatment with other sodium salts including Na2S, NazSO4, NaHSO4, Na2SO3, NaHSO3 and NaAc did not show significant effects on the growth of cucumber hypocotyls and radicles. These salts do not release H2S. Based on above results, it can be concluded that the effects of NariS in the experiment depended on the H2S rather than other compounds derived from NariS, and the alleviating effects might related with its function in modulating antioxidant capacity and amylase activities.

Effects of Heat Treatment on Flavonoids Content and Antioxidant Capacity of Buckwheat (Fagopyrum tataricum Gaert) Flour Ethanolic Extracts

The chemical composition, total flavonoids and antioxidant capacity of 50% ethanolic extracts from raw and cooked buckwheat flour from southwest of China were determined. The heat treatment used to gelatinize the flour starch significantly reduced the total flavonoids in the extract from 83.52 to 67.36 mg 100 g 1 of dry matter in the raw and cooked flour, respectively. The antioxidant capacity of the extracts was evaluated using autooxidation in a β carotene linoleate model system (AA or AAC), DPPH radical scavenging assay (IP) and oxygen radical absorbance capacity (ORAC) assay. Values for raw buckwheat flour extract were 97.84, 874.31, 76.45 and 94.92% for AA, AAC, ORAC and IP, respectively, while values in cooked buckwheat flour were 86.14, 842.88, 63.93 and 94.74% for AA, AAC, ORAC and IP, respectively. Values before cooked and raw buckwheat flour extracts were significantly different ( P <0.05) for AA, AAC, and ORAC.

Effects of dietary supplementation with algal astaxanthin on growth,pigmentation,and antioxidant capacity of the blood parrot (Cichlasoma citrinellum × Cichlasoma synspilum )

An algal astaxanthin feeding trial was carried out to investigate the ef fects of natural astaxanthin from Haematococcus pluvialis as feed additives on growth, pigmenting efficacy and antioxidant capacity in blood parrot(C ichlasoma citrinellum × C ichlasoma. synspilum). Tissue total antioxidant capacity(TAC), superoxide dismutase(SOD), catalase(CAT) and maleic dialdehyde(MDA) were chosen as measures of its antioxidant capacity. All fish which received an astaxanthin(from micro-algal H. pluvialis) supplemented diet with 400 mg/kg of astaxanthin, after 50 days of feeding, the astaxanthin-fed fish displayed a pinkcolored skin and the control-fed fish displayed a grayish skin. For the growth, the weight gains of controlfed fish and astaxanthin-fed fish were 200% and 300%, respectively. Samples of skin and scales were used for analysis of total carotenoids and astaxanthin content, and fish feeding astaxanthin showed significantly( P <0.05) higher concentrations than the control group, indicating that the pigmentation of this fish had been significantly improved by dietary astaxanthin. Compared with the control fish, pigmented fish had lower SOD, CAT and MDA and higher TAC. It can be concluded that supplementation with dietary astaxanthin could eff ectively enhance growth, skin coloration and the antioxidant capacity of this fish. This study will provide a reference for application of natural astaxanthin from H. pluvialis as feed additives in blood parrot artificial breeding. Our data is also useful in ornamental fish farming, especially when the retentivity of astaxanthin in the skin and scales are involved. It is leading to the possibility of increasing the pigmentation of farmed-fish by adding the powdered form of H. pluvialis to the diet as an ef fective pigment.