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.

Volatile components,total phenolic compounds,and antioxidant capacities of worm-infected Gomphidius rutilus

This study evaluated the effects of worm infection on the volatile components,total phenolic compounds,and antioxidant capacities of Gomphidius rutilus.G.rutilus without worms(GW),G.rutilus infected by a small amount of worms(GS;infected area<50%),and G.rutilus infected by a large amount of worms(GL;infected area>50%)were investigated.The volatile components of G.rutilus were analyzed by simultaneous distillation–extraction(SDE)and headspace solid-phase microextraction(HS-SPME)using gas chromatography–mass spectrometry(GC–MS).A total of 17 and 19 types of volatile compounds were detected,including ketones,alcohols,benzene,alkenes,aldehydes,esters,acids,and alkanes.Alcohols comprised the most abundant compound in GL,GS,and GW.The relative content of 1-octen-3-ol was the highest in all mushrooms.The concentration of eight-carbon(C8)compounds relative to the total volatile compounds varied widely,ranging from 40%(GW)to 64.34%(GS)and 84.42%(GS)and to 91.59%(GL),respectively,among the three samples.The antioxidant capability and the total phenolic contents of G.rutilus were evaluated in this study.The highest total phenolic content(TPC)of 192.23 mg GAE/g was found in GL,which differed significantly(P<0.05)from the latter two samples,whereas the lowest value of 156.11 mg GAE/g was found in GW.ABTS radical cation scavenging activity,FRAP ferric reducing antioxidant capacity(FRAP)radical scavenging activity,and oxygen radical absorbance capacity(ORAC)were investigated to screen the antioxidant properties of extracts.The contents of total phenolic compounds and their antioxidant capacities in vitro showed significant correlations(P<0.01).Among the three types of samples,the phenolic compounds of GL exhibited the highest antioxidant capacity,showing the values of 0.089 mM TE/g for ABTS,0.949 mM Fe^2+E/g for FRAP,and 1.952 M TE/g for ORAC.However,regarding the total antioxidant capacity,GS exhibited the highest antioxidant capacity,showing the values of 0.002648 mM TE/g for ABTS,0.004437 mM Fe^2+E/g for FRAP,and 0.256μM TE/g for ORAC.In conclusion,HS-SPME was more suitable for the extraction of volatile aroma components from G.rutilus.GL had the most abundant aroma components.GL had the highest TPC and antioxidant capacity compared with those of GS and GW,whereas GS showed the opposite results.Interestingly,GS was found to have the highest total antioxidant capacity in vitro.Based on these measured indicators,worm infection had no negative effect on the quality of G.rutilus.Therefore,worm-infected G.rutilus can also be consumed by humans.

Preliminary Comparative Study on Antioxidant Capacities of Yak

The aim of the present experiment was to determine if there was an adaptation on plasma antioxidant capacities of yak under the malnutrition （fasting treatment）. Three castrated male yaks and equal numbers of indigenous male cattle and of castrated male cattleyak with mean body weight of 146 ± 5.0, 116 ±3.0 and 149 ± 5.0 kg, respectively, were used. The fasting period lasted for 6 d. Results showed that： plasma total antoxidative capacity （T-AOC） was no differences between the genotypes on the fasting 1 st, 3rd, and 6th （P 〉 0.05）, but the values were linear greater with fasting days for yak, however, it was inverse for indigenous cattle or cattle-yak; plasma xanthine oxidase （XOD） activities of indigenous cattle were less than yak＇s and cattleyak＇s on the fasting 1st and 3rd day （P 〈 0.05）, but the value of indigenous cattle was greater than yak＇s and cattleyak＇s on the fasting 6th day （P 〈 0.05）. In a conclusion, plasma antioxidant capacities indicated that yaks have evolved an ability to survive in a starvation than indigenous cattle, and their crossbred-cattleyak also has inherited some of the adaptive characteristics.

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.

Effect of three cooking methods on nutrient components and antioxidant capacities of bamboo shoot(Phyllostachys praecox C.D. Chu et C.S. Chao)

Three cooking methods,namely boiling,steaming,and stir-frying for 5 to 10 min,were used to evaluate the effect on nutrient components,free amino acids,L-ascorbic acid,total phenolic contents,and antioxidant capacities of bamboo shoots(Phyllostachys praecox).Results showed that boiling and stir-frying had a great effect on the nutrient components and they decreased the contents of protein,soluble sugar,and ash,and caused a great loss in the total free amino acids(decreased by 38.35% and 34.86%,respectively).Significant differences(P<0.05) in free amino acids were observed in the samples cooked by different methods.Stir-fried bamboo shoots had a high fat content which increased by 528.57% because of the addition of edible oil.After boiling,the L-ascorbic acid and total phenolic contents were significantly reduced,while steaming increased total phenolic content by 3.98% and stir-frying well-preserved L-ascorbic acid(78.87% of its previous content).Results of the antioxidative property study showed that stir-frying could increase antioxidant capacities of bamboo shoots.It is concluded that stir-frying is more suitable for bamboo shoots because it could obtain the maximum retention of antioxidant capacities.

Enhanced Antioxidant Capacities in vivo Caused by the Change in Key Constituent of Terminalia chebula Retz. Treated with Tibet Traditional Process

In order to investigate the chemical-biological relationship caused by the special processing technology,the constituent＇s content and antioxidant capacity in vivo of Euphorbia fischeriana Steud processing Terminalia chebula Retz. have been tested. Taking T. chebula Retz. as control,the content of gallic acid is analyzed with high performance liquid chromatography（HPLC） method. The results show that the increase of gallic acid concentration from 4.54% to 7.46% leads to enhancement of the antioxidant capacities in vivo of the E. fischeriana Steud processing T. chebula Retz. The significant antioxidant capacity in vivo（p〈0.05） of the processed product possesses is better than the unprocessed herb. Its superoxide dismutase（SOD）and malondia-ldehyde（MDA） contents in serum,the MDA content in liver can match the effects of vitamine E when administered at high dosage.

Phenolic Composition and Antioxidant Capacities of Chinese Local Pummelo Cultivars' Peel

China is one of the main production areas of pummelo [Citrus grandis(L.) Osbeck.] in the world and has lots of distinctive local cultivars.Systematic research on the detection of phenolics and antioxidant capacity of peels of mature local cultivars pummelo fruits is rare.In the current study,phenolic composition and content in peels(flavedo and albedo) of ten Chinese local pummelo cultivars were determined using Ultraviolet Spectrophotometer and High Performance Liquid Chromatography(HPLC),and their antioxidant capacities were evaluated using 2,2-diphenyl-1-picrylhydrazyl(DPPH) radicals,ferric reducing antioxidant power(FRAP),and 2,2′-azino-bis(3-ethylbenzthiazoline-6)-sulfonic acid(ABTS)methods in the current study.The research not only provides data that support making full use of the resources of Chinese local pummelo cultivars,but also lays the theoretical basis for research of pummelo fruit nutrition and health values.The results showed that the total phenolic(TP)content in albedo was significantly higher than that in flavedo;on the contrary,the total flavonoid(TF) content was lower in the albedo than in the flavedo.C.grandis ‘Hongxinyou' flavedo contained the highest TP contents,C.grandis ‘Liangpingyou 78-8' flavedo contained the highest TF contents,and C.grandis ‘Guanxi Miyou' albedo contained the highest TP and TF contents.Naringenin,hesperetin,diosmin,and gallic acid were the predominant phenolics in the flavedo,whereas hesperetin,diosmin,rutin,chlorogenic acid,and gallic acid were the primary phenolics in the albedo.The flavedo of C.grandis ‘Yubei Shatianyou' and the albedo of C.grandis ‘Dianjiang Baiyou' had the highest antioxidant potency composite(APC) indexes.Overall,the ‘Yubei Shatianyou' flavedo and the ‘Dianjiang Baiyou' albedo are excellent sources of antioxidants and have the greatest potential value for exploitation and utilization.

Long-term feeding of sand rice(Agriophyllum squarrosum seed)can improve the antioxidant capacity of mice

Unhealthy eating habits with sugar-rich and high-fat foods can bring nutritional imbalance and other chronic diseases. At present, there is an increasing demand in regulating human sub-health through functional foods. Agriophyllum squarrosum(L.) Moq., a pioneer plant native to sand dunes with ecological restoration function, is a traditional food plant of sand regions and Mongolian folk medicine. Numerous studies have confirmed that A. squarrosum seed, also called sand rice, has high nutritional value. However, the long-term health effects of eating sand rice remain unclear. To better explore and evaluate its long-term effects, hereby, ICR mice were fed with sand rice flour at different ratios(control, 60% and 95%) for 100 days. Results show that the growth and blood glucose level curve of these experimental mice were lower and more stable than that of the control. In addition, mice fed pure sand rice ingredient(95%) gained more stable body weight and blood glucose after 28 days, which revealed that sand rice is a food with comprehensive nutritional value and rarely negatively impacts the body growth performance. Our data also demonstrates that, the content of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C) provided the lowest level in the blood of mice with a diet of pure sand rice ingredient, 0.48, 4.14, 0.91, 3.03 mmol/L, respectively. Also, T-SOD and GSH-PX activity provided a high level in mice with pure sand rice gradient, which significantly increased by 36%(T-SOD)and 19%(GSH-PX) compared to the control. These results suggest that long term intake of the pure sand rice ingredients is more helpful for stabilizing blood lipid and improve antioxidant capacity and beneficial to people suffering from chronic disease. This study supplies the first animal evidence to support the claim that sand rice is a promising functional food with comprehensive nutrition in the future. We are confident that, with increasing demands of daily sand rice usage, planting A. squarrosum in the vast desert regions will further increase the local economy and ecological restoration when coping with global warming.

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.

Rice Grains from Slightly Saline Field Exhibited Unchanged Starch Physicochemical Properties but Enhanced Nutritional Values

This study aims to investigate grain quality and nutritional values of rice(Pokkali,a salt-tolerant cultivar;RD73,a new cultivar improved from KDML105 introgressed with Saltol QTL from Pokkali,and KDML105,a moderately salt-susceptible cultivar)grown under non-saline(0.04–0.87 dS/m)and slightly saline(1.08–4.83 dS/m)field conditions.The results revealed that salinity caused significant reduction in grain size but significant increments in reducing sugar and total protein contents in the grains.Nevertheless,the amounts of starch in the grains of KDML105 and Pokkali rice genotypes were unaffected by the stress.The starch granule size distribution was also unaffected by salinity.Interestingly,only starch from Pokkali was significantly diminished in amylose content,from 19.18%to 16.99%.Accordingly,parameters relating to starch gelatinization,retrogradation,and pasting properties of KDML105 and RD73 were unaffected by salinity;only Pokkali showed a significant increase in percentage of retrogradation along with a significant reduction in gelatinization enthalpy.In the saline field,total phenolic content and antioxidant capacity in the grains of all rice cultivars tended to increase,particularly in Pokkali.On average,essential element contents in grains from the saline-treated plants showed a 33%,32%,32%,22%,20%,11%,and 10%increase in total P,N,K,Mg,Zn,Fe,and Ca content,respectively.Interestingly,total Fe content exhibited the greatest percentage of increments in KDML105(187%).Taken together,cultivation of rice in the slightly saline field did not alter its eating and cooking qualities,while enhanced some nutritional properties such as proteins,minerals,and secondary metabolites like phenolic compounds.

Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple leaves.Furthermore,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with Cf.Following Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related genes.The overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected leaves.The results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes activity.This jointly contributed to GLS resistance in apple.

Effects of Loading Methods on the Color,Phenolic and Antioxidant Properties of Cured Tobacco Leaves

[Objective] To investigate the effects of different loading methods on tobacco leaf quality.[Method] With tobacco comb,tobacco clamp,and tobacco basket,color,phenolic compounds and their antioxidant capacity of flue-cured tobacco leaves were studied.[Result] The results showed that L＊,a＊ and b＊ values of tobacco leaves packaged by tobacco clamp and comb were higher than those of tobacco basket and no significant differences were found beween values of a＊ and b＊,however,between L＊ and h values,remarkable differences existed among three loading methods.Total phenolic content and chlorogenic acid content of tobacco leaves loaded by tobacco comb kept the highest,followed by smoke clamp and tobacco basket （P＜0.05）.On the other hand,rutin content showed little differences among treatments.The order of the antioxidant properties,such as DPPH free radical scavenging activity and reducing powder,of tobacco leaves by different loading methods was tobacco comb ＞ tobacco clamp ＞ loose basket and a positive relationship was found of antioxiang property with total phenolic content and chlorogenic acid content.[Conclusion] In view of tobacco leaves quality and antioxidant property,loading method with tobacco comb proved to be a better choice.

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.

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.

Tannins from Canarium album with potent antioxidant activity

The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS） and nuclear magnetic resonance （NMR） analyses The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using l,l-diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing/antioxidant power （FRAP） model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.

Antioxidant power of phytochemicals from Psidium guajava leaf

Dried ground leaves of Psidium guajava L. (guava) were extracted by water and aqueous ethyl alcohol 50% (1:10) ratio, and the total phenolic content in the extracts was determined spectrophotometrically according to Folin- Ciocalteu’s phenol method and calculated as gallic acid equivalent (GAE). Remarkably high total phenolic content 575.3 ±15.5 and 511.6±6.2 mg of GAE/g of dried weight material (for ethanol guava leaf extracts and water guava leaf extracts, respectively) were obtained. The antioxidant activity of lyophilized extracts was determined at ambient temperature by means of a 2,2-diphenyl-1-picrylhydryzyl (DPPH˙) colorimetry with detection scheme at 515 nm. The activity was evalu- ated by the decrease in absorbance as the result of DPPH˙ color change from purple to yellow. The higher the sample concentration used, the stronger was the free radical-scavenging effect. The results obtained showed that ascorbic acid was a substantially more powerful antioxidant than the extracts from guava leaf. On the other hand, the commercial guava leaf extracts and ethanol guava leaf extracts showed almost the same antioxidant power whereas water guava leaf extracts showed lower antioxidant activity. The parameter EC50 and the time needed to reach the steady state to EC50 concentration ( TEC50 ) affected the antiradical capacity of the sample. The antioxidant efficiency (AE) has been shown to be a more ade- quate parameter for selecting antioxidants than the widely used EC50. This study revealed that guava leaf extracts comprise effective potential source of natural antioxidants.

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.

Dietary isoleucine improved flesh quality,muscle antioxidant capacity,and muscle growth associated with AKT/TOR/S6K1 and AKT/FOXO3a signaling in hybrid bagrid catfish(Pelteobagrus vachelli♀×Leiocassis longirostris♂)

Background:Muscle is the complex and heterogeneous tissue,which comprises the primary edible part of the trunk of fish and mammals.Previous studies have shown that dietary isoleucine(Ile)exerts beneficial effects on growth in aquatic animals.However,there were limited studies regarding the benefits of Ile on fish muscle and their effects on flesh quality and muscle growth.Thus,this study was conducted to explore whether dietary Ile had affected flesh quality and muscle growth in hybrid bagrid catfish(Pelteobagrus vachelli♀×Leiocassis longirostris♂).Methods:A total of 630 hybrid fish,with an initial average body weight of 33.11±0.09 g,were randomly allotted into seven experimental groups with three replicates each,and respectively fed seven diets with 5.0,7.5,10.0,12.5,15.0,17.5,and 20.0 g Ile/kg diets for 8 weeks.Results:In the present study,we demonstrated that Ile significantly:(1)increased muscle protein and lipid contents and the frequency distribution of myofibers with≤20μm and≥50μm of diameter;(2)improved pH value,shear force,cathepsin B and L activities,hydroxyproline content,resilience,cohesiveness,and decreased cooking loss,lactate content,hardness,springiness,gumminess,and chewiness;(3)decreased reactive oxygen species(ROS),malondialdehyde(MDA),and protein carbonyl(PC)contents,GCLC and Keap1 mRNA levels,and up-regulated CuZnSOD,CAT,GPX1a,GST,and Nrf2 mRNA levels;(4)up-regulated the insulin-like growth factor 1,2(IGF-1,IGF-2),insulin-like growth factor 1 receptor(IGF-1R),proliferating cell nuclear antigen(PCNA),Myf5,Myod,Myog,Mrf4,and MyHC mRNA levels,and decreased MSTN mRNAlevel;(5)increased muscle protein deposition by activating AKT-TOR-S6K1 and AKT-FOXO3a signaling pathways.Conclusion:These results revealed that dietary Ile improved flesh quality,which might be due to increasing nutritional content,physicochemical,texture parameters,and antioxidant ability;promoting muscle growth by affecting myocytes hyperplasia and hypertrophy,and muscle protein deposition associated with protein synthesis and degradation signaling pathways.Finally,the quadratic regression analysis of chewiness,ROS,and protein contents against dietary Ile levels suggested that the optimal dietary Ile levels for hybrid bagrid catfish was estimated to be 14.19,12.36,and 12.78 g/kg diet,corresponding to 36.59,31.87,and 32.96 g/kg dietary protein,respectively.

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.