Constitutively Elevated Levels of Putrescine and Putrescine-Generating Enzymes Correlated with Oxidant Stress Resistance in Conyza bonariensis and Wheat

Changes in ascorbate and glutathione levels and in activities of ascorbate peroxidase, catalase, dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST), and superoxide dismutase (SOD) were investigated in tobacco mosaic virus (TMV)-inoculated lower leaves and in non-inoculated upper leaves of Nicotiana tabacum L. cv Xanthi-nc. In separate experiments the effects of exogenous salicylic acid (SA) were also studied. Symptom appearance after TMV inoculation was preceded by a slight, transient decline of ascorbate peroxidase, GR, GST, and SOD activities in the inoculated lower leaves, but after the onset of necrosis these activities and the glutathione level substantially increased. Ascorbic acid level and DHAR activity declined and dehydroascorbate accumulated in the inoculated leaves. In upper leaves, the glutathione level and the activities of GR, GST, and SOD increased 10 to 14 d after TMV inoculation of the lower leaves, concomitantly with the development of systemic acquired resistance. From the six distinct SOD isoenzymes found in tobacco leaves, only the activities of Cu,Zn-SOD isoenzymes were affected by TMV. SA injection induced DHAR, GR, GST, and SOD activities. Catalase activities were not modified by TMV infection or SA treatment. It is supposed that stimulated antioxidative processes contribute to the suppression of necrotic symptom development in leaves with systemic acquired resistance.     

Silicon-mediated alleviation of Mn toxicity in Cucumis sativus in relation to activities of superoxide dismutase and ascorbate peroxidase

The effects of exogenous silicon (Si) on plant growth, activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and catalase, and concentrations of ascorbate and glutathione were investigated in cucumber (Cucumis sativus L.) plants treated with excess manganese (Mn) (600 microM). Compared with the treatment of normal Mn (10 microM), excess Mn significantly increased H2O2 concentration and lipid peroxidation indicated by accumulation of thiobarbituric acid reactive substances. The leaves showed apparent symptoms of Mn toxicity and the plant growth was significantly inhibited by excess Mn. The addition of Si significantly decreased lipid peroxidation caused by excess Mn, inhibited the appearance of Mn toxicity symptoms, and improved plant growth. This alleviation of Mn toxicity by Si was related to a significant increase in the activities of SOD, APX, DHAR and GR and the concentrations of ascorbate and glutathione.     

Exogenous salicylic acid alleviates effects of long term drought stress and delays leaf rolling by inducing antioxidant system

Salicylic acid (SA) is one of the important signal molecules modulating plant responses to environmental stress. In this study, the effects of exogenous SA on leaf rolling, one of drought avoidance mechanisms, and antioxidant system were investigated in Ctenanthe setosa during long term drought stress. The plants were subjected to 38-day drought period and they were treated with or without SA (10⁻⁶ M) on the 25th, 27th and 29th days of the period. Leaf samples were harvested on the 30th, 34th and 38th days. Some antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, glutathione reductase), reactive oxygen species (hydrogen peroxide and superoxide) and lipid peroxidation were determined during the drought period. Treatment with SA prevented water loss and delayed leaf rolling in comparison with control leaves. Exogenous SA induced all antioxidant enzyme activities more than control leaves during the drought. Ascorbate and glutathione, α-tocopherol, carotenoid and endogenous SA level were induced by the SA treatment. Levels of reactive oxygen species were higher in SA treated plants than control ones on the 34th day. Their levels on the 38th day, however, fastly decreased in SA treated plants. SA treatment prevented lipid peroxidation while the peroxidation increased in control plants. The results showed that exogenous SA can alleviate the damaging effect of long term drought stress by decreasing water loss and inducing the antioxidant system in the plant having leaf rolling, alternative protection mechanism to drought.     

Rapid regulatory effect of tri-iodothyronine (T3) on antioxidant enzyme activities in a fish Anabas testudineus (Bloch): short-term in vivo and in vitro study

The short-term action of thyroid hormone tri-iodothyronine (T3) was studied in vivo and in vitro on antioxidant enzyme activities in a teleost Anabas testudineus (Bloch). T3 injection in vivo (200 ng) in normal fish decreased the lipid peroxidation products and increased superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) activities after 30 min. T3 in vitro (10(-6) M) increased the antioxidant activities of catalase, glutathione reductase (GR), GPx and glutathione level after 15/30 min, except SOD, substantiating in vivo effects in normal fish. The results suggest a rapid regulatory effect of thyroid hormone in vivo and in vitro, in the removal of reactive oxygen species in A testudineus.     

Effects of exogenous salicylic acid on manganese toxicity, element contents and antioxidative system in cucumber

The effects of salicylic acid (SA) on manganese (Mn) toxicity in cucumber plants (Cucumis sativus L.) were studied by investigating the symptoms, plant growth, lipid peroxidation, antioxidative enzymes and antioxidants. Excess Mn caused serious chlorosis and inhibited the growth of cucumber plants, and dramatically increased accumulation of Mn in both shoots and roots, furthermore, inhibited the absorption of Ca, Mg and Zn. Addition of SA decreased the transport of Mn from roots to shoots, alleviated the inhibition of Ca, Mg and Zn absorption induced by excess Mn, reduced the toxicity symptoms and promoted the plant growth. The accumulation of reactive oxygen species (ROS) significantly increased in cucumber leaves exposed to excess Mn, and resulted in the lipid peroxidation, which was indicated by accumulated concentration of thiobarbituric acid-reactive substances (TBARS). Addition of SA significantly decreased the level of ROS and lipid peroxidation. Activities of antioxidant enzymes showed different changes, addition of SA inhibited catalase (CAT) and ascorbate peroxidase (APX) activities, while increased activities of superoxide dismutase (SOD), peroxidase (POD), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) in cucumber leaves exposed to excess Mn. As important antioxidants, ascorbate and glutathione contents in cucumber leaves exposed to excess Mn were significantly increased by SA treatment.     

Exogenous salicylic acid alleviates NaCl toxicity and increases antioxidative enzyme activity in <Emphasis Type="Italic">Lycopersicon esculentum</Emphasis>

Effects of exogenous salicylic acid (SA) on plant growth, contents of Na, K, Ca and Mg, activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and catalase (CAT), and contents of ascorbate and glutathione were investigated in tomato (Lycopersicon esculentum L.) plants treated with 100 mM NaCl. NaCl treatment significantly increased H₂O₂ content and lipid peroxidation indicated by accumulation of thiobarbituric acid reactive substances (TBARS). A foliar spray of 1 mM SA significantly decreased lipid peroxidation caused by NaCl and improved the plant growth. This alleviation of NaCl toxicity by SA was related to decreases in Na contents, increases in K and Mg contents in shoots and roots, and increases in the activities of SOD, CAT, GPX and DHAR and the contents of ascorbate and glutathione.     

Manganese-excess induces oxidative stress,lowers the pool of antioxidants and elevates activities of key antioxidative enzymes in rice seedlings

Manganese (Mn) is an essential element for plant growth but in excess, specially in acidic soils, it can become phytotoxic. In order to investigate whether oxidative stress is associated with the expression of Mn toxicity during early seedling establishment of rice plants, we examined the changes in the level of reactive oxygen species (ROS), oxidative stress induced an alteration in the level of non-enzymic antioxidants and activities of antioxidative enzymes in rice seedlings grown in sand cultures containing 3 and 6 mM MnCl₂. Mn treatment inhibited growth of rice seedlings, the metal increasingly accumulated in roots and shoots and caused damage to membranes. Mn treated plants showed increased generation of superoxide anion (O₂ ^.−), elevated levels of H₂O₂ and thiobarbituric acid reactive substances (TBARS) and decline in protein thiol. The level of nonprotein thiol, however, increased due to Mn treatment. A decline in contents of reduced ascorbate (AsA) and glutathione (GSH) as well as decline in ratios of their reduced to oxidize forms was observed in Mn-treated seedlings. The activities of antioxidative enzymes superoxide dismutase (SOD) and its isoforms Mn SOD, Cu/Zn SOD, Fe SOD as well as guaiacol peroxidase (GPX) increased in the seedlings due to Mn treatment however, catalase (CAT) activity increased in 10 days old seedlings but it declined by 20 days under Mn treatment. The enzymes of Halliwell-Asada cycle, ascorbate peroxidase (APX) monodehydoascorbate reductase (MDHAR), dehyroascorbate reductase (DHAR) and glutathione reductase (GR) increased significantly in Mn treated seedlings over controls. Results suggest that in rice seedlings excess Mn induces oxidative stress, imbalances the levels of antioxidants and the antioxidative enzymes SOD, GPX, APX and GR appear to play an important role in scavenging ROS and withstanding oxidative stress induced by Mn.     

Active Oxygen-producing and -scavenging Enzymes in Pepper Leaves Infected with Xanthomonas campestris pv. vesicatoria

Lipoxygenase (LOX), peroxidase (POX), superoxide dismutase (SOD) and catalase (CAT) activities were determined in pepper (Capsicum annuum) leaves infected with Xanthomonas campestris pv. uesicatoria, from 3 to 15 days after inoculation, before symptom appearance and during the development of the disease. Strong Stimulation of LOX and POX activities was observed in infected leaves at an advanced stage of the disease (12–15 days after inoculation), when bacterial water-soaked spots and a slight chlorosis of the inoculated leaf areas were evident and a decrease in chlorophyll content of infected tissue was detected. The infection also induced a significant increase in CAT activity at the day 9 and a decrease in SOD and CAT activities at the day 12. On the basis of the changes observed, uncontrolled production of active oxygen species at advanced stages of infection is hypothesized.     

夜间低温胁迫对番茄叶片活性氧代谢及AsA-GSH循环的影响

以番茄品种‘辽园多丽’为试材,利用人工气候室模拟设施生产中的夜间低温胁迫环境,研究9℃和6℃夜低温对番茄叶片活性氧代谢和AsA-GSH循环的影响。结果显示:9℃和6℃夜间低温胁迫3～9d可诱导番茄叶片中超氧阴离子(O2.-)产生速率、过氧化氢(H2O2)和丙二醛(MDA)含量上升;抑制过氧化物酶(POD)、过氧化氢酶(CAT)的活性,增加超氧化物歧化酶(SOD)和AsA-GSH循环中抗坏血酸过氧化物酶(APX)、脱氢抗坏血酸还原酶(DHAR)、谷胱甘肽还原酶(GR)的活性,并提高还原型抗坏血酸(AsA)、还原型谷胱甘肽(GSH)、氧化型谷胱甘肽(GSSG)的含量。研究表明,在夜间低温胁迫过程中,增加的番茄叶片中SOD活性和AsA-GSH循环清除活性氧的能力并未与氧还原的速率一致,从而导致番茄叶片中活性氧的累积,使细胞膜系统受到一定破坏,在6℃处理的植物中尤为明显。     

Antioxidant defences of the apoplast

Summary The apoplast of barley and oat leaves contained superoxide dismutase (SOD), catalase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione reductase activities. The activities of these enzymes in the apoplastic extracts were greatly modified 24 h after inoculation with the biotrophic fungal pathogenBlumeria graminis. The quantum efficiency of photosystem II, which is related to photosynthetic electron transport flux, was comparable in inoculated and healthy leaves during this period. Apoplastic soluble acid invertase activity was also modified in inoculated leaves. Inoculation-dependent increases in apoplastic SOD activity were observed in all lines. Major bands of SOD activity, observed in apoplastic protein extracts by activity staining of gels following isoelectric focusing, were similar to those observed in whole leaves but two additional minor bands were found in the apoplastic fraction. The apoplastic extracts contained substantial amounts of dehydroascorbate (DHA) but little or no glutathione (GSH). Biotic stress decreased apoplastic ascorbate and DHA but increased apoplastic GSH in resistant lines. The antioxidant cycle enzymes may function to remove apoplastic H₂O₂ with ascorbate and GSH derived from the cytoplasm. DHA and oxidized glutathione may be reduced in the apoplast or returned to the cytosol for rereduction.Abbreviations AA reduced ascorbate - APX ascorbate peroxidase - DHA dehydroascorbate (oxidised ascorbate) - DHAR dehydroascorbate reductase - G6PDH glucose-6-phosphate dehydrogenase - GSH reduced glutathione - GSSG glutathione disulphide - GR glutathione reductase - MDHA monodehydroascorbate - MDHAR monodehydroascorbate reductase - SOD superoxide dismutase     

Effect of lanthanum ions (La3+) on the reactive oxygen species scavenging enzymes in wheat leaves

Physiological effects of lanthanum ions on the activities of the enzymes in the reactive oxygen species (ROS) scavenging system in leaves of wheat (Triticum aestivum L.) seedlings were studied. Wheat leaves treated in Hogland solution with 0.1 mM LaCl₃ for 48 h showed increased levels of superoxide dismutase (SOD), catalase (CAT), ascorbate-specific peroxidase (AsA-POD), and dehydroascorbate reductase (DHAR). However, a minor effect was observed on the levels of monodehydroascorbate reductase (MDAR) and glutathione reductase (GR), which regulate the release of energy required by the ROS scavenging system. The whole system was linked up by H⁺ transmission. Our results indicated that the activities of the enzymes that function directly to remove ROS were elevated by La³⁺ treatment, which is consistent with the observations that La³⁺-treated plants had increased tolerance to environmental stresses. The remaining levels of MDAR and GR suggested that these two enzymes might be regulated differently from that of the other four enzymes studied.     

硅和白粉菌诱导接种对黄瓜幼苗白粉病抗性影响的研究

研究了硅酸盐和诱导接种白粉菌对黄瓜活性氧代谢、SiO2含量和抗病性的影响．结果表明,诱导接种能使叶片的超氧自由基(O2^-)产生速率、H2O2和丙二醛(MDA)含量升高,加硅接种处理的O2^-产生速率、H202和MDA含量明显低于不加硅接种处理．诱导接种能使叶片的过氧化氢酶(CAT)、过氧化物酶(POD)活性升高,超氧化物歧化酶(SOD)活性降低．加硅接种处理植株叶片的CAT、POD和SOD活性明显高于不加硅接种处理．诱导接种提高叶片的抗坏血酸(AsA)和还原型谷胱甘肽(GSH)含量,加硅处理的AsA含量明显低于不加硅处理,GSH含量高于不加硅处理．无论接种与否,加硅处理的SiO2含量显著高于不加硅处理,病情指数明显低于不加硅处理．     

Effect of flooding on the activities of some enzymes of activated oxygen metabolism,the levels of antioxidants,and lipid peroxidation in senescing tobacco leaves

Effects of flooding on the activities of some enzymes of activated oxygen metabolism, the levels of antioxidants, and lipid peroxidation in senescing leaves of tobacco were investigated. As judged by the decrease in chlorophyll and protein levels, flooding accelerated the senescence of tobacco leaves. Total peroxide and the lipid peroxidation product, malondialdehyde, increased in both control and flooding-treated leaves with increasing duration of the experiment. Throughout the duration of the experiment, flooded leaves had higher levels of total peroxide and malondialdehyde than did control leaves. Flooding resulted in an increase in peroxidase and ascorbate peroxidase activities and a reduction of superoxide dismutase activity in the senescing leaves. Glycolate oxidase, catalase, and glutathione reductase activities were not affected by flooding. Flooding increased the levels of total ascorbate and dehydroascorbate. Total glutathione, reduced form glutathione, or oxidized glutathione levels in flooded leaves were lower than in control leaves during the first two days of the experiment, but were higher than in control leaves at the later stage of the experiment. Our work suggests that senescence of tobacco induced by flooding may be a consequence of lipid peroxidation possibly controlled by superoxide dismutase activity. Our results also suggest that increased rates of hydrogen peroxide in leaves of flooded plants could lead to increased capacities of the scavenging system of hydrogen peroxide.Abbreviations GSH reduced form glutathione - GSSG oxidized form glutathione - GSSG reductase glutathione reductase - MDA malondialdehyde - SOD superoxide dismutase     

Fungal pathogen-induced changes in the antioxidant systems of leaf peroxisomes from infected tomato plants

Peroxisomes, being one of the main organelles where reactive oxygen species (ROS) are both generated and detoxified, have been suggested to be instrumental in redox-mediated plant cell defence against oxidative stress. We studied the involvement of tomato (Lycopersicon esculentum Mill.) leaf peroxisomes in defence response to oxidative stress generated upon Botrytis cinerea Pers. infection. The peroxisomal antioxidant potential expressed as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6) and glutathione peroxidase (GSH-Px, EC 1.11.1.19) as well as the ascorbate-glutathione (AA-GSH) cycle activities was monitored. The initial infection-induced increase in SOD, CAT and GSH-Px indicating antioxidant defence activation was followed by a progressive inhibition concomitant with disease symptom development. Likewise, the activities of AA-GSH cycle enzymes: ascorbate peroxidase (APX, EC 1.11.1.11), monodehydroascorbate reductase (MDHAR, EC 1.6.5.4), dehydroascorbate reductase (DHAR, EC 1.8.5.1) and glutathione reductase (GR, EC 1.6.4.2) as well as ascorbate and glutathione concentrations and redox ratios were significantly decreased. However, the rate and timing of these events differed. Our results indicate that B. cinerea triggers significant changes in the peroxisomal antioxidant system leading to a collapse of the protective mechanism at advanced stage of infection. These changes appear to be partly the effect of pathogen-promoted leaf senescence.     

渗透胁迫对黑麦幼苗活性氧和抗氧化酶活性的影响

用20%聚乙二醇(PEG 6000)研究了渗透胁迫对黑麦(Secale cereale L.)幼苗活性氧(reactive oxygen species, ROS)和主要抗氧化酶—— 超氧化物歧化酶(superoxide dismutase, SOD)、过氧化氢酶(catalase, CAT)、抗坏血酸过氧化物酶(ascorbate peroxidase, APX)和谷胱甘肽还原酶(glutathione reductase, GR)活性的影响。结果表明, 与对照相比, PEG处理明显提高了叶子和根中丙二醛(malondialdehyde, MDA)的含量、ROS的水平和以上4种抗氧化酶的活性。渗透胁迫下,叶子和根中MDA和ROS水平变化的规律基本相似, 但抗氧化酶活性在2种器官中表现不完全相同, 叶子中CAT的活性在对照和处理中无显著差异, 但在根中差异明显, 表明叶子中SOD、APX和GR在植物应答渗透胁迫中起重要作用, 而根中这4种抗氧化酶都参与植物对胁迫的反应。GR活性随PEG处理变化幅度显著高于其它抗氧化酶, 表明GR在黑麦应答渗透胁迫中所起作用可能强于其它抗氧化酶。     

Effects of exogenous spermidine on antioxidant system of tomato seedlings exposed to high temperature stress

The effects of foliar spraying with spermidine (Spd) on antioxidant system in tomato (Lycopersicon esculentum Mill.) seedlings were investigated under high temperature stress. The high temperature stress significantly inhibited plant growth and reduced chlorophyll (Chl) content. Application of exogenous 1 mM Spd alleviated the inhibition of growth induced by the high temperature stress. Malondialdehyde (MDA), hydrogen peroxide (H₂O₂) content and superoxide anion (O₂) generation rate were significantly increased by the high temperature stress, but Spd significantly reduced the accumulation of reactive oxygen species (ROS) and MDA content under the stress. The high temperature stress significantly decreased glutathione (GSH) content and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), but increased contents of dehydroascorbic acid (DHA), ascorbic acid (AsA), and oxidized glutathione (GSSG) in tomato leaves. However, Spd significantly increased the activities of antioxidant enzymes, levels of antioxidants and endogenous polyamines in tomato leaves under the high temperature stress. In addition, to varying degrees, Spd regulated expression of MnSOD, POD, APX2, APX6, GR, MDHAR, DHAR1, and DHAR2 genes in tomato leaves exposed to the high temperature stress. These results suggest that Spd could change endogenous polyamine levels and alleviate the damage by oxidative stress enhancing the non-enzymatic and enzymatic antioxidant system and the related gene expression.     

Antioxidant enzyme activities in embryologic and early larval stages of turbot

The antioxidant enzymes superoxide dismutase (SOD; EC 1.15.1.1), catalase (EC 1.11.1.6), selenium-dependent glutathione peroxidase (SeGPX; EC 1.11.1.9), glutathione reductase (EC 1.6.4.2) and DT-diaphorase (EC 1.6.99.2), plus total GPX activity (sum of SeGPX and Se-independent GPX activities), were studied in 13 500 g supernatants of embryos and 3-day and 11-day post-hatch larvae of turbot Scophthalmus maximus L. SOD activity decreased progressively during development from embryos to 11-day-old larvae, indicative of a decreased need to detoxify superoxide anion radical (O₂⁻). In contrast, catalase, SeGPX and glutathione reductase activities increased progressively from embryos to 11-day-old larvae, indicative of an increased need to metabolize hydrogen peroxide (H₂O₂) and organic peroxides. Consistent with the latter changes, levels of lipid peroxides (i.e. thiobarbituric acid reactive substances) increased 13-fold from embryos to 3-day-old larvae, whilst total peroxidizable lipid was indicated to decrease. Increases were seen for NADPH-dependent DT-diaphorase (after hatching) and total GPX (between 3 and 11 days post-hatch) activities, whilst no change was found in NADH-dependent DT-diaphorase activity. Overall, the results demonstrate a capacity for early life-stages of S. maximus to detoxify reactive oxygen species (O₂⁻ and H₂O₂) and other pro-oxidant compounds (organic peroxides, redox cycling chemicals). Furthermore, qualitative and quantitative antioxidant changes occur during hatching and development, possibly linked to such events as altered respiration rates (SOD changes) and tissue reorganization and development (catalase, SeGPX, lipid peroxidation).     

Effect of zinc nutritional status on activities of superoxide radical and hydrogen peroxide scavenging enzymes in bean leaves

The effect of varied zinc (Zn) supply on the activities of superoxide dismutase (SOD), ascorbate (AsA) peroxidase, glutathione (GSSG) reductase, catalase and guaiacol peroxidase was studied in leaves of bean (Phaseolus vulgaris) plants grown for 15 days in nutrient solution. Zinc deficiency severely decreased plant growth and the leaf concentrations of soluble protein and chlorophyll. Resupply of Zn to deficient plants for up to 72h restored protein concentrations more rapidly than chlorophyll and plant growth. With the exception of guaiacol peroxidase, the activities of all enzymes were significantly decreased by Zn deficiency, in particular GSSG reductase and SOD. Within 72h of resupplying Zn to deficient plants, the enzyme activities reached the level of the Zn sufficient plants. The results indicate severe impairment in the ability of Zn-deficient leaves to enzymically scavenge O₂ ^- and H₂O₂. Consequences and reasons of this impairment are discussed in terms of photooxidation of chloroplast pigments and inhibition of the biosynthesis of the related scavenger enzyme proteins.     

Zymogram profiling of superoxide dismutase and catalase activities allows Saccharomyces and non-Saccharomyces species differentiation and correlates to their fermentation performance

Aerobic organisms have devised several enzymatic and non-enzymatic antioxidant defenses to deal with reactive oxygen species (ROS) produced by cellular metabolism. To combat such stress, cells induce ROS scavenging enzymes such as catalase, peroxidase, superoxide dismutase (SOD) and glutathione reductase. In the present research, we have used a double staining technique of SOD and catalase enzymes in the same polyacrylamide gel to analyze the different antioxidant enzymatic activities and protein isoforms present in Saccharomyces and non-Saccharomyces yeast species. Moreover, we used a technique to differentially detect Sod1p and Sod2p on gel by immersion in NaCN, which specifically inhibits the Sod1p isoform. We observed unique SOD and catalase zymogram profiles for all the analyzed yeasts and we propose this technique as a new approach for Saccharomyces and non-Saccharomyces yeast strains differentiation. In addition, we observed functional correlations between SOD and catalase enzyme activities, accumulation of essential metabolites, such as glutathione and trehalose, and the fermentative performance of different yeasts strains with industrial relevance.