Specific Activities Of Catalase Research Articles

Impact of Palm Kernel Oil (PKO) Biodiesel-Contaminated Catfish on Hepatic Function of Rat

The purpose of the present study was to assess the effects of consumption of catfish (Clarias gariepinus) exposed to palm kernel oil (PKO) biodiesel on functions and oxidative status of liver of albino rat. The author measured the responses of growth performance (average daily weight gain, feed conversion ratio, body weight, and relative liver weight), oxidative stress, and indices of liver functions of rat placed on feed formulated with catfish exposed to borehole water mixed with different concentrations of PKO biodiesel ( 0 % w/v, 0.1 % w/v, 0.25 % w/v). The results showed that fish exposed to PKO biodiesel had no effect on relative liver weight, but average body weight was significantly reduced, serum levels of total and direct bilirubin were significantly elevated while those of bilirubin and globulin were significantly reduced. However, specific activities of catalase (CAT), superoxide dismutase (SOD) and glutathione-s-transferase (GST) of serum of rats fed with catfish exposed to lower concentration of PKO biodiesel (BD 0.1) were significantly higher than those of rats fed with catfish exposed to higher concentration of PKO biodiesel (BD 0.25) (p<0.05) while both are significantly lower than that of the control rats (p<0.05). Serum level of MDA in test rats increased significantly (p<0.05) as the concentration of PKO biodiesel increased. The data clearly demonstrate that consumption of catfish exposed to PKO biodiesel can result in liver dysfunction at a degree not dependent on concentration of PKO biodiesel by a mechanism of oxidative stress which is dependent on the concentration of PKO biodiesel.

Gonadal steroids negatively modulate oxidative stress in CBA/Ca female mice infected with P. berghei ANKA.

We decreased the level of gonadal steroids in female and male mice by gonadectomy. We infected these mice with P. berghei ANKA and observed the subsequent impact on the oxidative stress response. Intact females developed lower levels of parasitaemia and lost weight faster than intact males. Gonadectomised female mice displayed increased levels of parasitaemia, increased body mass, and increased anaemia compared with their male counterparts. In addition, gonadectomised females exhibited lower specific catalase, superoxide dismutase, and glutathione peroxidase activities in their blood and spleen tissues compared with gonadectomised males. To further study the oxidative stress response in P. berghei ANKA-infected gonadectomised mice, nitric oxide levels were assessed in the blood and spleen, and MDA levels were assessed in the spleen. Intact, sham-operated, and gonadectomised female mice exhibited higher levels of nitric oxide in the blood and spleen compared with male mice. MDA levels were higher in all of the female groups. Finally, gonadectomy significantly increased the oxidative stress levels in females but not in males. These data suggest that differential oxidative stress is influenced by oestrogens that may contribute to sexual dimorphism in malaria.

Nox gene expression and cytochemical localization of hydrogen peroxide in Polyporus umbellatus sclerotial formation.

The effect of temperature shift on Polyporus umbellatus sclerotial development was investigated. Micromorphology of the sclerotia was observed by using scanning electron microscopy (SEM). The cytochemical localization of H2O2 expressed as CeCl3 deposition at the subcellular level was observed by using transmission electron microscopy (TEM). Nox gene expression in sclerotia and mycelia was detected by quantitative real-time PCR (qRT-PCR) analysis. In addition, superoxide dismutase (SOD) and catalase (CAT) specific activities increased during sclerotial development and decreased after the antioxidant diphenyleneiodonium (DPI) was used. Results indicated that the temperature shift treatment induced P. umbellatus sclerotial formation. Compared with the mycelia, the Nox gene was respectively upregulated by 10.577-, 30.984- and 25.469-fold in the sclerotia of SI, SD and SM stages respectively. During the sclerotial formation, H2O2 accumulation was observed in the cell walls or around the organelle membranes of the mycelial cells. The antioxidant DPI decreased the generation of H2O2 in mycelial cells. The specific activity of SOD and CAT levels was decreased significantly by DPI. The activity of the two antioxidant enzymes in the mycelia increased much more during sclerotial formation (p < 0.05). Oxidative stress was closely associated with sclerotial development in P. umbellatus induced by temperature shift treatment.

Fish exposure to nano-TiO2 under different experimental conditions: Methodological aspects for nanoecotoxicology investigations

The ecotoxicology of nano-TiO2 has been extensively studied in recent years; however, few toxicological investigations have considered the photocatalytic properties of the substance, which can increase its toxicity to aquatic biota. The aim of this work was to evaluate the effects on fish exposed to different nano-TiO2 concentrations and illumination conditions. The interaction of these variables was investigated by observing the survival of the organisms, together with biomarkers of biochemical and genetic alterations. Fish (Piaractus mesopotamicus) were exposed for 96h to 0, 1, 10, and 100mg/L of nano-TiO2, under visible light, and visible light with ultraviolet (UV) light (22.47J/cm2/h). The following biomarkers of oxidative stress were monitored in the liver: concentrations of lipid hydroperoxide and carbonylated protein, and specific activities of superoxide dismutase, catalase, and glutathione S-transferase. Other biomarkers of physiological function were also studied: the specific activities of acid phosphatase and Na,K-ATPase were analyzed in the liver and brain, respectively, and the concentration of metallothionein was measured in the gills. In addition, micronucleus and comet assays were performed with blood as genotoxic biomarkers. Nano-TiO2 caused no mortality under any of the conditions tested, but induced sublethal effects that were influenced by illumination condition. Under both illumination conditions tested, exposure to 100mg/L showed an inhibition of acid phosphatase activity. Under visible light, there was an increase in metallothionein level in fish exposed to 1mg/L of nano-TiO2. Under UV light, protein carbonylation was reduced in groups exposed to 1 and 10mg/L, while nucleus alterations in erythrocytes were higher in fish exposed to 10mg/L. As well as improving the understanding of nano-TiO2 toxicity, the findings demonstrated the importance of considering the experimental conditions in nanoecotoxicological tests. This work provides information for the development of protocols to study substances whose toxicity is affected by illumination conditions.

Oxidative Stress Response of Blakeslea trispora Induced by Iron Ions During Carotene Production in Shake Flask Culture

The adaptive response of the fungus Blakeslea trispora to the oxidative stress induced by iron ions during carotene production in shake flask culture was investigated. The culture response to oxidative stress was studied by measuring the specific activities of catalase (CAT) and superoxide dismutase (SOD). The addition of 1.0 mM of FeCl3 to the medium was associated with a mild oxidative stress as evidenced by remarkable increase of the specific activities of SOD and CAT. On the other hand, the addition 5.0 mM of FeCl3 caused a strong oxidative stress resulting in a drastic decrease in carotene concentration. The oxidative stress in B. trispora changed the composition of the carotenes and caused a significant increase of γ-carotene ratio. The highest concentration of carotenes (115.0 ± 3.5 mg/g dry biomass) was obtained in the basal medium without the addition of FeCl3 after 8 days of fermentation. In this case, the carotenes consisted of β-carotene (46.3 %), γ-carotene (40.1 %), and lycopene (13.6 %). The addition of 1.0 mM of FeCl3 into the medium did not change the concentration of carotenes. But, the composition of carotenes was changed with a drastic increase of γ-carotene ratio (61.6 %) and a decrease in β-carotene and lycopene ratio (31.2 and 7.2 %, respectively).

Neuroprotective effects of inhaled lavender oil on scopolamine-induced dementia via anti-oxidative activities in rats

Lavender is used in traditional medicines in Asia, Europe, ancient Greece and Rome, and was mentioned in the Bible and in ancient Jewish texts. Also, lavender is reported to be an effective medical plant in treating inflammation, depression, stress and headache. The present study was undertaken in order to investigate the antioxidant and antiapoptotic activities of the lavender essential oils from Lavandula angustifolia ssp. angustifolia Mill. and Lavandula hybrida Rev. using superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) specific activities, total content of reduced glutathione (GSH), malondialdehyde (MDA) level (lipid peroxidation) and DNA fragmentation assays in male Wistar rats subjected to scopolamine-induced dementia rat model. In scopolamine-treated rats, lavender essential oils showed potent antioxidant and antiapoptotic activities. Subacute exposures (daily, for 7 continuous days) to lavender oils significantly increased antioxidant enzyme activities (SOD, GPX and CAT), total content of reduced GSH and reduced lipid peroxidation (MDA level) in rat temporal lobe homogenates, suggesting antioxidant potential. Also, DNA cleavage patterns were absent in the lavender groups, suggesting antiapoptotic activity. Taken together, our results suggest that antioxidant and antiapoptotic activities of the lavender essential oils are the major mechanisms for their potent neuroprotective effects against scopolamine-induced oxidative stress in the rat brain.

Показники системи антиоксидантного захисту клітин Desulfuromonas аcetoxidans за впливу ферум (ІІІ) цитрату й арґентум нітрату

Desulfuromonas acetoxidans are obligative anaerobic sulfur bacteria of the aquatic sedimental environments that are able to Fe 3+ -dissimilative reduction. The influence of various concentrations of ferric (III) citrate and silver nitrate on specific catalase activity and reduced glutathione synthesis by D. аcetoxidans cells has been determined under their cultivation with fumarate addition and with absence of sulfur. Specific catalase activity increased with enhancing of ferric (III) citrate concentration and duration of bacterial cultivation under the addition of this salt. Under the influence of ferric (III) citrate, maximal catalase activity has been observed on the fourth day of cultivation with addition of 5 mM of investigated metal salt. Under the influence of ferric (III) citrate, increa­sing in reduced glutathione content has been observed on the second day of bacterial growth with addition of 1 mM of investigated metal salt. The highest specific catalase activity was determined on the second day of bacterial growth under the influence of all concentration range of investigated metal salt. The reduced glutathione content under silver nitrate exposure varied depending on the cultivation time and metal concentration. The maximum reduced glutathione content has been observed on the second day of bacterial growth under the effect of 6 µM of AgNO 3 . Keywords: reduced glutathione, catalase, sulfur bacteria, Desulfuromonas acetoxidans , ferrum, argentum.

Leptospira interrogans Catalase Is Required for Resistance to H 2 O 2 and for Virulence

Pathogenic Leptospira spp. are likely to encounter higher concentrations of reactive oxygen species induced by the host innate immune response. In this study, we characterized Leptospira interrogans catalase (KatE), the only annotated catalase found within pathogenic Leptospira species, by assessing its role in resistance to H(2)O(2)-induced oxidative stress and during infection in hamsters. Pathogenic L. interrogans bacteria had a 50-fold-higher survival rate under H(2)O(2)-induced oxidative stress than did saprophytic L. biflexa bacteria, and this was predominantly catalase dependent. We also characterized KatE, the only annotated catalase found within pathogenic Leptospira species. Catalase assays performed with recombinant KatE confirmed specific catalase activity, while protein fractionation experiments localized KatE to the bacterial periplasmic space. The insertional inactivation of katE in pathogenic Leptospira bacteria drastically diminished leptospiral viability in the presence of extracellular H(2)O(2) and reduced virulence in an acute-infection model. Combined, these results suggest that L. interrogans KatE confers in vivo resistance to reactive oxygen species induced by the host innate immune response.

Female plants of Hippophae salicifolia D. Don are more responsive to cold stress than male plants

Hippophae salicifolia D. Don (Seabuckthorn) grows in stressful environment of high altitude under conditions of low temperature and low availability of water. We have studied gender based differences in physiochemical response to cold stress in male and female plants of Seabuckthorn. After 24h of cold stress about 32 and 66% higher electrolyte leakage (EL) was recorded in male and female plants respectively. Relative water content (RWC) at the end of 24h stress was higher in male plants (~64%) compared to female plants (~60%). Proline content in leaf samples of cold stressed male and female plants also increased upon cold stress. After 24h about 2.7 fold higher amount of proline was assessed in male and female in comparison to control plants. Similarly, about two fold increase in the specific activities of superoxide dismutase (SOD) and catalase was also observed upon cold stress in male and female plants. These findings have important inferences for community of molecular biologists exploring seabuckthorn genome for agronomically important genes.

Improved production of carotenes from synthetic medium by Blakeslea trispora in a bubble column reactor

The carotene production from a synthetic medium sterilized at initial pH 11.0 by Blakeslea trispora in a bubble column reactor was investigated. Under the above conditions the fungus formed compact aggregates (pellets). As a consequence, a mild oxidative stress in B. trispora was occurred indicated by the specific activities of superoxide dismutase (SOD) and catalase (CAT). The oxidative stress resulted in a significant increase in carotene production and a change in the biosynthesis of carotenes. The highest concentration of carotenes (85.0mg/g dry biomass) was obtained after 8 days of fermentation. In this case, the proportion of β-carotene, γ-carotene, and lycopene was 52.42%, 45.43%, and 2.15%, respectively. Bubble column reactor has a potential for carotene production from synthetic medium sterilized at initial pH 11.0.

Potentized homeopathic drug Arsenicum Album 30C inhibits intracellular reactive oxygen species generation and up-regulates expression of arsenic resistance gene in arsenite-exposed bacteria Escherichia coli

To examine if potentiated homeopathic drug Arsenicum Album 30C (Ars Alb 30C) can reduce sodium arsenite-induced toxicity in Escherichia coli. E. coli were exposed to low arsenite insult after they grew up to log phase in standard Luria-Bertani medium. E. coli were treated with 1 or 2 mmol/L sodium arsenite alone (control), or Ars Alb 30C was added to the medium of a subset of sodium arsenite-treated bacteria (drug-treated), or homeopathically agitated alcohol was added to the medium containing a subset of sodium arsenite-treated bacteria (placebo-treated). A sub-set of untreated E. coli served as the negative control. Glucose uptake, specific activities of hexokinase, lipid peroxidase (LPO), superoxide dismutase (SOD) and catalase, intra- and extra-cellular sodium arsenite content, cell growth, cell membrane potential, DNA damage, intracellular reactive oxygen species (ROS), adenosine triphosphate (ATP) and free glutathione content and expressions of arsB and ptsG gene in normal control, sodium arsenite-treated, drug-treated and placebo-treated E. coli were analyzed. Treatments were blinded and randomized. In sodium arsenite-treated E. coli, glucose uptake, intracellular ROS, LPO and DNA damage increased along with decrease in the specific activities of hexokinase, SOD and catalase, intracellular ATP and free glutathione contents and cell membrane potential and growth, and there were increases in expression levels of arsB gene and ptsG gene. Ars Alb 30C administration reduced arsenic toxicity in E. coli by inhibiting generation of ROS and increasing tolerance to arsenite toxicity and cell growth. Ars Alb 30C ameliorated arsenic toxicity and DNA damage, validating efficacy of ultra-highly diluted remedies used in homeopathy.

Consumption of baru seeds [Dipteryx alata Vog.], a Brazilian savanna nut, prevents iron-induced oxidative stress in rats

The protective effect of plant-based foods in human health has been attributed to the presence of bioactive compounds in all parts of the plants. A previous study found a high level of minerals, tannins and phytic acid in the baru nut (Dipteryx alata Vog.), which is a native fruit of the Brazilian savanna. This study investigated the antioxidant activity (AA) of the aqueous and ethyl acetate extracts of the baru nut and the effect of the consumption of this nut on the oxidative status of rats supplemented orally with iron. The AA was evaluated in vitro using the ferric reducing antioxidant power (FRAP), β-carotene/linoleic acid system and free-radical scavenging (DPPH) assays. The total polyphenol concentration was determined spectrophotometrically using the Folin–Ciocalteu reagent. The in vivo study was conducted in male Wistar rats that were fed an AIN-93M diet with or without 10% baru nut or 1% phytic acid and supplemented daily with iron or saline by gavages for 17days. The liver, heart and spleen were collected for the determination of the malondialdehyde (MDA), carbonyl protein and iron concentrations. The specific activities of catalase, glutathione reductase, glutathione peroxidase and glutathione S-transferase were also determined in these tissues. A T test was used to compare the results among the rats groups and between the different baru nut extracts (p<0.05). The aqueous extract of the baru nut contained a higher level of phenolic compounds and a higher antioxidant activity, as measured by FRAP and the β-carotene/linoleic system, relative to the EtOAc extract. The iron supplementation reduced the body weight gain, increased the levels of iron and MDA in the liver and the spleen and increased the carbonyl levels in all three tissues. Consumption of the baru nut reduced the carbonyl levels in the liver, heart and spleen of the iron-supplemented rats (p=0.002, 0.012 and 0.036, respectively) relative to the heart carbonyl level of rats that were fed the control diet (p=0.000); it also marginally reduced the iron-induced lipid oxidation in the liver (p=0.117) and the spleen (p=0.074). Phytic acid reduced the carbonyl level in the spleen (p=0.020) and marginally reduced the carbonyl level in the liver (p=0.098) of iron-supplemented rats. These results demonstrated that the consumption of the baru nut protects tissues against iron-induced oxidative stress, and the phytic acid from the baru nut may be partially responsible for this protective effect; however, other compounds such as phenols may also be involved.

Interacting effects of pyrethroid and hormone on catalase and protein for toxicity amelioration in the freshwater fish, Clarias batrachus

Ameliorating effects of cortisol and T3 on alphamethrin-dependent changes in the catalase (CAT) and protein profile of the freshwater catfish, Clarias batrachus, were studied. CAT activity and specific activity decreased in the liver, heart, kidney, and intestine after exposure to alphamethrin for 14 days. The administration of cortisol to alphamethrin-exposed fish brought the activity and specific activity of CAT up to their control values. The protein content decreased in different tissues of the fish after exposure to alphamethrin. The administration of T3 to alphamethrin-exposed fish reduced the protein content to the control value. Therefore, it can be suggested that cortisol and T3 may be used to ameliorate the toxicological effects of alphamethrin in fish.

Soluble epoxide hydrolase contamination of specific catalase preparations inhibits epoxyeicosatrienoic acid vasodilation of rat renal arterioles

Cytochrome P-450 metabolites of arachidonic acid, the epoxyeicosatrienoic acids (EETs) and hydrogen peroxide (H(2)O(2)), are important signaling molecules in the kidney. In renal arteries, EETs cause vasodilation whereas H(2)O(2) causes vasoconstriction. To determine the physiological contribution of H(2)O(2), catalase is used to inactivate H(2)O(2). However, the consequence of catalase action on EET vascular activity has not been determined. In rat renal afferent arterioles, 14,15-EET caused concentration-related dilations that were inhibited by Sigma bovine liver (SBL) catalase (1,000 U/ml) but not Calbiochem bovine liver (CBL) catalase (1,000 U/ml). SBL catalase inhibition was reversed by the soluble epoxide hydrolase (sEH) inhibitor tAUCB (1 μM). In 14,15-EET incubations, SBL catalase caused a concentration-related increase in a polar metabolite. Using mass spectrometry, the metabolite was identified as 14,15-dihydroxyeicosatrienoic acid (14,15-DHET), the inactive sEH metabolite. 14,15-EET hydrolysis was not altered by the catalase inhibitor 3-amino-1,2,4-triazole (3-ATZ; 10-50 mM), but was abolished by the sEH inhibitor BIRD-0826 (1-10 μM). SBL catalase EET hydrolysis showed a regioisomer preference with greatest hydrolysis of 14,15-EET followed by 11,12-, 8,9- and 5,6-EET (V(max) = 0.54 ± 0.07, 0.23 ± 0.06, 0.18 ± 0.01 and 0.08 ± 0.02 ng DHET·U catalase(-1)·min(-1), respectively). Of five different catalase preparations assayed, EET hydrolysis was observed with two Sigma liver catalases. These preparations had low specific catalase activity and positive sEH expression. Mass spectrometric analysis of the SBL catalase identified peptide fragments matching bovine sEH. Collectively, these data indicate that catalase does not affect EET-mediated dilation of renal arterioles. However, some commercial catalase preparations are contaminated with sEH, and these contaminated preparations diminish the biological activity of H(2)O(2) and EETs.

Sunflower cotyledons cope with copper stress by inducing catalase subunits less sensitive to oxidation

Copper is an essential trace element for living organisms, in excess, can be toxic to the cell because of its capacity to generate reactive oxygen species (ROS). Catalase (CAT) catalyzes the dismutation of hydrogen peroxide into water and dioxygen and in plants it is located in peroxisomes and glyoxysomes. Different metals can induce changes in CAT activity, but the mechanism underlying its changes is unclear. After 4 h of treatment with 5 and 10 μM CuCl 2 a decrease in the specific CAT activity was detected in sunflower cotyledons of post-germinative heterotrophic seedlings. At 8 h of treatment, 5 μM Cu 2+ produced an induction of CAT activity while only a complete recovery to control values was observed for 10 μM Cu 2+ treated seedlings. These activity variations were not related to the level of CAT protein expression, but they did correlate with the oxidative state of the CAT protein. This indicates that the mechanism of CAT inactivation by Cu 2+ involves oxidation of the protein structure. The level of the mRNA of CATA3 and CATA4 increased with the presence of the metal after 4 h of exposure. These CAT genes code for the synthesis of CAT subunits less sensitive to oxidation, which would prevent the copper-induced oxidative inactivation of CAT.

Neuroprotective effect of the methanolic extract of Hibiscus asper leaves in 6-hydroxydopamine-lesioned rat model of Parkinson's disease

While the Hibiscus asper Hook.f. (Malvaceae) is a traditional herb largely used in tropical region of the Africa as vegetable, potent sedative, tonic and restorative, anti-inflammatory and antidepressive drug, there is very little scientific data concerning the efficacy of this. The antioxidant and antiapoptotic activities of the methanolic extract of Hibiscus asper leaves (50 and 100 mg/kg) were assessed using superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) specific activities, total glutathione (GSH) content, malondialdehyde (MDA) level (lipid peroxidation) and DNA fragmentation assays in male Wistar rats subjected to unilateral 6-hydroxydopamine (6-OHDA)-lesion. In 6-OHDA-lesioned rats, methanolic extract of Hibiscus asper leaves showed potent antioxidant and antiapoptotic activities. Chronic administration of the methanolic extract (50 and 100 mg/kg, i.p., daily, for 7 days) significantly increased antioxidant enzyme activities (SOD, GPX and CAT), total GSH content and reduced lipid peroxidation (MDA level) in rat temporal lobe homogenates, suggesting antioxidant activity. Also, DNA cleavage patterns were absent in the 6-OHDA-lesioned rats treated with methanolic extract of Hibiscus asper leaves, suggesting antiapoptotic activity. Taken together, our results suggest that the methanolic extract of Hibiscus asper leaves possesses neuroprotective activity against 6-OHDA-induced toxicity through antioxidant and antiapoptotic activities in Parkinson's disease model.

Stimulation of the biosynthesis of carotenes by oxidative stress in Blakeslea trispora induced by elevated dissolved oxygen levels in the culture medium

The adaptive response of the fungus Blakeslea trispora to the oxidative stress induced by elevated dissolved oxygen concentrations during carotene production was investigated by measuring the specific activities of catalase (CAT) and superoxide dismutase (SOD) and the micromorphology of the fungus using a computerized image analysis system. Changes in the ratio of the volume of air (Va) over the medium and the volume of medium (Vm) in the flask caused changes of the morphology of microorganism from clumps to pellets and increases in the specific activities of CAT and SOD. The oxidative stress in B. trispora resulted in a significant increase in carotene production, and a maximum proportion of β-carotene (60%), γ-carotene (50%), and lycopene (10%) (as percentages of total carotenes) was observed at a ratio Va/Vm of 15.7, 4.0 and 1.5, respectively. The highest concentration of carotenes (115.0mg/g dry biomass) was obtained in Va/Vm ratio of 9.0.

Characterization of stress processes ofPhaffia rhodozymastress-resistant mutant

A carotenoid-less Phaffia rhodozyma mutant (MCP 325) exhibited significantly higher resistance to oxidative stressors such as menadione, H2O2 and K2Cr2O7 than its astaxanthin-producing parental strain (MCP 324). The absence of carotenoids in the mutant did not explain this phenomenon. The cause of the decreased superoxide, hydroxyl radical and glutathione contents, the increased peroxide concentration and the elevated specific activity of catalase under uninduced conditions may be a second mutation. Peroxide treatment induced specific catalase activity in the mutant but not in the parental strain. Regulation of these processes led to the result that, in spite of the mutations, the two strains exhibited the same multiplication rate and generation time.

Gestational Cadmium Exposure-Induced Ovotoxicity Delays Puberty through Oxidative Stress and Impaired Steroid Hormone Levels

Cadmium (Cd), an environmental pollutant, has been shown to be highly toxic to both humans and animals. Its widespread industrial use has led to its accumulation in the environment. Cd has been shown to target multiple organs following acute intoxication, causing nephrotoxicity, immunotoxicity, osteotoxicity, and reproductive toxicity. Cd can cross the placental barrier and cause a wide range of defects during fetal development. The current study was aimed to assess the effect of Cd on the female reproductive system. Female rats were exposed to Cd [50/200 ppm] from embryonic day 9 to 21 through drinking water. Serum steroid hormone concentrations, hematological parameters, antioxidant enzyme levels, and ovarian histopathology were described. Water consumption, gravid uterine/body weight decreased in both the doses of Cd-treated dams. The hematological parameters analyzed in rat pups showed a significant reduction in both doses of Cd studied, while hemoglobin showed a significant reduction in 200 ppm Cd treatment alone. MCHC levels did not show any variation in 50 ppm Cd treatment, while 200 ppm Cd treatment significantly increased. Specific activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and serum testosterone, estradiol, and progesterone were significantly decreased. The levels of hydrogen peroxide and lipid peroxidation were increased in 50 and 200 ppm Cd-treated rats. These changes were accompanied with disrupted ovarian histoarchitecture, an extended estrous cycle, and delayed pubertal onset in Cd-treated rats. The data generated from the present study suggest that gestational Cd treatment induces ovarian toxicity and reproductive dysfunction through increased oxidative stress.

Oxidative stress and morphological changes in Blakeslea trispora induced by enhanced aeration during carotene production in a bubble column reactor

The oxidative stress and the morphological changes in Blakeslea trispora induced by enhanced aeration during carotene production in a bubble column reactor was investigated. Enhanced aeration caused changes of the morphology of microorganism from aggregates with large projected area to aggregates with small projected area. This morphological differentiation of the fungus was associated with high oxidative stress as evidenced by increase of the specific activities of superoxide dismutase (SOD) and catalase (CAT). The oxidative stress in B. trispora resulted in a significant increase in carotene production. The highest concentration of carotenes (55.0 ± 2.5 mg/g dry biomass) was obtained at aeration rate of 4 vvm. Very high oxidative stress in B. trispora caused a change in the biosynthesis of carotenes resulting an increase in γ-carotene concentration. The maximum proportion of β-carotene (91.68%), γ-carotene (44.67%), and lycopene (11.54% of total carotenes) was observed at aeration rates of 4, 5, and 5 vvm, respectively. The external addition of butylated hydroxytoluene (BHT) and hydrogen peroxide in the medium did not improve the production of carotenes.