Gene expression response of mutagenic breeding of Acidithiobacillus sp. FJ2 to different concentrations of uranium low grade ore

219-227Acidithiobacillus ferrooxidans (At. f) is a bacterium involved in the bioleaching process. In the present study, we investigated the effects of Acidithiobacillus sp. FJ2 induced with diethyl sulfate (DES) as mutagen on the bioleaching of low grade uranium ore. The comparison was carried out within 5, 10, 15, 25 and 50% uranium ore pulp densities in the bioleaching system. The impact of the induction of Acidithiobacillus sp. FJ2 was determined by Eh and pH values, concentrations of Fe2+ and uranium extraction rates at 24 h intervals. The results showed that DES with 0.8% may lead to an obvious change on bacteria leading to improvement of bioleaching capability in 5, 10, 15% pulp densities. However, the bioleaching activity of the original bacteria was more efficient than DES-induced bacteria at 25 and 50% pulp densities. The gene expression results in 0.8% DES treated bacteria indicated that the bacteria attempt to adjust in the bioleaching systems (with different pulp densities) through decreased cyc2 and increased rus, cyc1 and coxB levels. These results suggest that uranium may induce oxidative stress in the wild and treated strains in the high pulp density, while the bacteria tried to survive and gain more energy from the iron oxidation. However, when the amount of uranium increased, the mutants couldn’t cope up woth the enhanced stress in 25 and 50% pulp densities. It may be due to inhibitory effect of uranium toxicity on adaptive processes which may change the trends

Investigation the UV Effect on Uranium Bioleaching Process in Acidithiobacillus sp FJ2 ‎and its Possible Consequences on the CoxB Gene Sequence ‎

Introduction: The increasing use of uranium as a suitable source of energy in various industries has led to the depletion of high-grade uranium mines in different countries. Today, the uranium bioleaching process has been used in different countries for easy and cheap access to uranium. In this process, microorganisms are used to extract uranium from low-grade mines. Materials and methods: The Acidithiobacillus sp. FJ2 bacterium was exposed to UV radiation. Then, the uranium bioleaching process was conducted in the presence of bacteria exposed to UV and non-exposed bacteria. In followings, this gene was amplified by PCR technique after DNA extraction from bacterial species and coxB gene primer design. Subsequent to gene sequencing and editing with bioedit software, the final sequence of the coxB gene was determined from both bacterial species. Later than, the sequences were examined and compared to prove the presence or absence of the mutation in the radiation sample. Results: The amount of uranium extraction in the presence of bacteria exposed to UV reached to 100% on the second day at the 5% pulp density, whereas the 96.36% extraction yield was obtained on the thirteenth day in pulp density of 50%. This amount was recorded in an unexposed bacterium, in the third and thirteenth days at 5& 50% pulp densities, respectively. The coxB gene sequence was identical in both bacterial specimens. Discussion and conclusion: In this study, UV irradiation to Acidithiobacillus sp. FJ2 increased the rate of uranium bioleaching in the pulp density of 5%, whereas uranium extraction yield was sustained in the 50% pulp density. These effects were independent to the coxB gene

Gene expression response of mutagenic breeding of Acidithiobacillus sp. FJ2 to different concentrations of uranium low grade ore

Acidithiobacillus ferrooxidans (At. f) is a bacterium involved in the bioleaching process. In the present study, we investigated the effects of Acidithiobacillus sp. FJ2 induced with diethyl sulfate (DES) as mutagen on the bioleaching of low grade uranium ore. The comparison was carried out within 5, 10, 15, 25 and 50% uranium ore pulp densities in the bioleaching system. The impact of the induction of Acidithiobacillus sp. FJ2 was determined by Eh and pH values, concentrations of Fe2+ and uranium extraction rates at 24 h intervals. The results showed that DES with 0.8% may lead to an obvious change on bacteria leading to improvement of bioleaching capability in 5, 10, 15% pulp densities. However, the bioleaching activity of the original bacteria was more efficient than DES-induced bacteria at 25 and 50% pulp densities. The gene expression results in 0.8% DES treated bacteria indicated that the bacteria attempt to adjust in the bioleaching systems (with different pulp densities) through decreased cyc2 and increased rus, cyc1 and coxB levels. These results suggest that uranium may induce oxidative stress in the wild and treated strains in the high pulp density, while the bacteria tried to survive and gain more energy from the iron oxidation. However, when the amount of uranium increased, the mutants couldn’t cope up woth the enhanced stress in 25 and 50% pulp densities. It may be due to inhibitory effect of uranium toxicity on adaptive processes which may change the trends

Potential Protective Effect of Pretreatment with Caraway Essential Oil in vivo Model of Iron Nanoparticle-induced Liver Injury

Recently, there has been a great deal of interest in the use of the medicinal plants with high antioxidant compounds for curing liver injuries induced by hepatoxcitic agents. This study was to assess the protective effect of Carum carvi L. essential oil (E.O) on the hepatoxitic rats induced by overdose of iron oxide nanoparticles (NPs). The rats were distributed to 4 groups. In negative control group (NC), the rats received normal saline and DMSO daily for 3 days. In control group (C), iron oxide nanoparticles (Fe2O3) (200 mg/kg b.w) was injected daily for 3 days. In the treatment groups, iron oxide nanoparticles plus E.O at 100 & 200 mg/kg b.w were injected daily for 3 days. In following, cytochrome P450 (CYP450), glutathione S-transferase (GST), glutathione (GSH), aspartate transaminase (AST), alkaline phosphatase (ALP) and alanine transaminase (ALT) were estimated at 72 h after NP-treatment. The administration of the E.O could return considerably the decrease of the GST and GSH levels as well as the increase of the level of AST induced by iron oxide NPs. These results are in agreement with histopathological results. The data indicated that E.O provided an efficient prevention against iron oxide NPs-induced hepatotoxicity in rats

Zataria multiflora Essential oil Prevent Iron Oxide Nanoparticles-induced Liver Toxicity in Rat Model

Over loading of iron oxide nanoparticles can causes the liver injury through overproduction of free radicals. Zataria multiflora Boiss. (Lamiaceae) has been used for many years in folk medicine due to its antioxidant and antibacterial activities. This study evaluates -for the first time- the effect of Z. multiflora essential oil (EO) against iron oxide nanoparticles hepatotoxicity in rat model. Male Wistar rats were divided randomly into 4 groups; control group (C), non-treated control group (NT), treatment groups, nanoparticles plus Z. multiflora EO at 100 and 200 mg/kg b.w. In following, the liver and blood tissue were collected for estimating antioxidant / oxidative stress parameters including lipid peroxidation (LP), glutathione (GSH), glutathione-S-transferase (GST), and liver enzyme asparate transaminase (AST) and also histopathological examinations. Iron oxide nanoparticles toxicity produced a significant increase in the levels of LP, ferric reducing ability of plasma (FRAP), and AST activity concomitant with decrease in the levels of GSH and GST activity compared to the control group. However, in the treatment groups received Z. multiflora EO, the levels of LP and AST activity reduced together with increasing in GSH content and GST activity were significantly reported. Histopathological studies also supported the biochemical assessments indicating hepatic improvements induced by nanoparticles. Z. multiflora EO protected the liver from injuries induced by iron oxide nanoparticles which can be correlated with its antioxidant activities. This can be a valuable candidate in modulating the oxidative hepatic injuries

Sequencing of the rus gene before and after the mutation with DES in the bacterial Acidithiobacillus sp. FJ2

In Acidithiobacillus ferrooxidans, the proteins present in the electron transfer pathway cause ferrous iron oxidation which leads to uranium extraction. The relationship between gene sequence and uranium extraction has not been investigated yet. Based on the changes in uranium extraction, the changes of rus gene sequence can reveal the direct and accurate role of this protein. For this purpose, a random mutation was induced in native Acidithiobacillus sp. FJ2 by two doses of 0.8% and 1% of DES. Then, the bacteria was transferred into a medium which contained 50% uranium ore to carry out the bioleaching process. After measuring the amount of the extracted uranium, iron, Eh and pH, genomic DNA was extracted to investigate the rusticyanin gene (rus) sequence sent for sequencing after performing PCR. Then, the wild-type gene sequence was compared with the mutant by Bioedit v7.2.5 software. The results showed that uranium extraction increased by mutant bacteria with DES 1% between 7-11 days in comparison with wild bacteria. However, there has been no change in the functional areas of the rusticyanin gene. It seems that DES affected other effective genes in the electron transport chain or regulatory areas, which required further studies

Evaluation the effect of uranium ore concentrations on the cyc2 gene expression in the mutated Acidithiobacillus sp. FJ2

Introduction: The uranium bioleaching process is performed using Acidithiobacillus ferrooxidans. This bacterium is capable of iron oxidation by an electron transport chain. One of the most important components of this chain is the cyc2 gene product that involved in the oxidation process of iron. Materials and methods: Evaluation of UV mutated (60, 120 and 180s) Acidithiobacillus sp. FJ2 cyc2gene in the presence of uranium ore concentrations, has been implemented in this project. For this purpose, the original and mutated bacteria were cultivated in the presence of uranium ore concentrations (5, 10, 15, 25 and 50%). Uranium extraction, variation of pH and Eh values were measured at 24 h intervals. Then, when the uranium extraction yield reached to 100%, gene expressions of cyc2 original and mutatedAcidithiobacillus sp. FJ2 were analyzed using Real-time PCR method. Results: The results of the experiments showed that, with increasing pulp density, the uranium extraction rate and oxidation activity of bacteria were reduced. In addition, the result of cyc2 gene expression showed that the target gene expression increases in the presence of uranium ore compared to sample with absence of uranium ore, andwith further increase of pulp density, due to the toxicity of uranium, shows a decreasing trend. Discussion and conclusion: The results of this study indicated that the mutation in the bacterium has a positive effect on the uranium bioleaching process, which can play an important role in the process of uranium bioleaching at high concentrations. In addition, with increasing pulp density due to uranium toxicity, there is a decreasing trend in the process of uranium extraction, which indicates the important role of this factor in the uranium bioleaching process

Evaluation of Gamma Irradiation Effect on the Oxidative Stress Factors in Septic Rats Treated With Iranian Plant Essential Oils

ABSTRACT Cuminum cyminum L. (CM), Zataria multiflora Boiss. (ZM) and Mentha piperita L. (MP) are traditional medicinal plants with various pharmacological properties. This study was designed to assess the role of gamma irradiation -a modern decontamination method- in hepatoprotective effects of their essential oil (E.Os) in septic rats induced by experimental cecal ligation and puncture (CLP) model. The rats were divided into 20 groups; sham-operated (SOP); CLP; CLP + CM, ZM and MP (E.Os) (100 & 200 mg/kg b.w) and CLP + gamma irradiated (10 and 25 kGy) E.Os (100 & 200 mg/kg b.w) as treatment groups. All E.Os were injected i.p immediately after sepsis induction. 24 hour after CLP, the rats were sacrificed and the liver tissue was examined considering lipid peroxiation (LP), glutathione (GSH) and myeloperoxidase (MPO) activity. The results indicated that CLP operation caused significant (P<0.05) increase in the LP and MPO levels concomitant with decreased GSH level. Administration of the E.Os (100 and 200 mg/kg b.w) extracted from non irradiated plants as well as the irradiated (10 and 25 kGy) plant E.Os could significantly (P<0.05) modulate the levels of LP, MPO and GSH. It can be concluded that all E.Os even after irradiation exposure could modulate the oxidative injury parameters related to liver damages in CLP rat model. In conclusion, the plant irradiation didn’t have any adverse effects on the hepatoprotective activities of the extracted oils

Assessment of the Protective Role of Herbal Drug Iberogast (STW5) in Prevention of Hepatic Histopathological Damage Caused by Acute Inflammation in Rats

Background and Objectives: Iberogast with commercial name of STW 5 is a well known herbal drug, which contains stable components of hydroethanolic extract from 9 different herbal drugs. This study was carried out with the purpose of assessing the protective effects of STW 5 in different doses on the hepatic histopathological damages induced by experimental cecal ligation and puncture (CLP) model in septic rats. Methods: In this experimental study, 36 rats were divided into six groups (six rats in each group): Sham-operated (SOP); CLP group; CLP+STW 5 (received doses of 2.5, 5, and 10mg/kgBW) as treatment groups; and CLP+Indomethacin (10mg/kgBW) as positive control. The herbal drug STW 5 and Indomethacin were injected ip, immediately after sepsis induction. After 24 hour, the rats were sacrificed and the liver tissue was qualitatively and quantitatively examined in terms of histological changes. The differences between the data were determined by one-way ANOVA and post hoc Tukey’s HSD and the significant levels were defined as p<0.05. Results: The findings indicated that increased level of infiltrated and/or sequestrated polymorphonuclear neutrophils (PMNs) and also, elevated level of histological index of the severity of liver injuries in the CLP group were not improved after treatment with Iberogast.Conclusion: Considering the results of this study, ip injection of STW 5 immediately after sepsis induction had no effect on the modulation of histological parameters related to liver damages in CLP rat model

Assessing the effect of Mentha longifolia essential oils on COX-2 expression in animal model of sepsis induced by caecal ligation and puncture

Context: Mentha longifolia L. (Lamiaceae), a traditional Iranian plant, possesses antimicrobial and antioxidant activities. Objective: We investigated the potential protective effects of M. longifolia essential oils (E.Os) on caecal ligation and puncture (CLP) induced liver injury. Materials and methods: Wistar Albino rats (n = 50) were grouped as follows: (1) a laparotomy group (LAP); (2) a CLP group (CLP); (3) the treatment groups received orally the E.Os (50 and 100 mg/kg b.w) and indomethacin (2 mg/kg b.w) for 2 weeks. The oxidative stress parameters, liver enzymes and prostaglandin E2 (PGE2) level were measured in liver and plasma tissues. The liver was also harvested for the real time PCR of cyclooxygenase (COX-2) expression following histopathological examinations. Results: The results indicated that the CLP operation significantly increased lipid peroxidation (LP) [1.79-fold], myeloperoxidase (MPO) [2.76-fold], PGE2 [1.56-fold] besides plasma aspartate aminotransferase (AST) [2.4-fold] and alanine aminotransferase (ALT) activities [2.22-fold], while, markedly reduced glutathione (GSH) [0.63-fold] and ferric reducing ability of plasma (FRAP) levels [0.63-fold]. Even COX2 expression significantly increased in the CLP group as compared to the LAP group. Treatments of rats with the E.Os could return all the hepatic and plasma biomarkers to the normal levels. These results were further confirmed by pathological examination on liver indicating that E.Os could successfully improve the CLP-induced liver injuries. Discussion and conclusions: Our findings suggest that E.Os is able to protect liver injuries against sepsis via modulating the oxidative stress parameters concomitant with the suppression of inflammatory reactions such as PGE2 and COX-2