Toxicity Effects of Engineered Iron Nanoparticles (Fe3O4) on the Growth, Cell Density, and Pigment Content of Chlorella vulgaris.

This study investigated the effects of Fe3O4 nanoparticles released from synthesized thiourea catalyst on the biological aspects of Chlorella vulgaris. Fe3O4 concentrations (0, 10, 100, 250, 500, 750, and 1000 mg L-1) were used for the exposure tests. Biological parameters of C. vulgaris, including cell density, cell viability, and pigment content, were assessed. Bioconcentration and bioaccumulation factors were evaluated for contaminated microalgae. Non-carcinogenic risks were then assessed using target hazard quotient (THQ) for potential risks in human consumptions. Findings showed that C. vulgaris cell number increased from 0 to 500 mg L-1 of Fe3O4 concentration. Chlorophyll a represented a time-dependent response, and greatest values were detected in 250 and 500 mg L-1 Fe3O4 at 4.2 and 4 mg/g, respectively. Chlorophyll b content showed a time-related manner in exposure to Fe3O4 with the highest values recorded at 250 mg L-1 after 96 h. Moreover, bioaccumulation displayed a dose-dependent response at 15,000 µg/g dw in 1000 mg L-1, whereas the lowest concentration was in the control group at 1700 µg/g dw. The bioconcentration factor showed a concentration-relevant decrease in all iron treatments and 10 mg L-1 of Fe3O4 represented the greatest BCF at 327.3611. Non-carcinogenic risks illustrated negligible hazard (THQ < 1) and the largest EDI and THQ were calculated in 1000 mg L-1 at 7.4332E-07 (mg kg-1 day-1) and 1.06189E-09, respectively. Together, iron is an essential trace element for biological purposes in aquatic systems, but in exceeding concentrations could impose toxicity effects to C. vulgaris populations.

Functional Quails Eggs using Enriched Spirulina during the Biosorption Process.

Spirulina platensis was included at 2.5%, 5%, and 7.5% of the diet as a phytobiotic either as a crude preparation or after enrichment by a biosorption process and fed to 126 Japanese quail and the eggs collected and examined for 6 weeks. Assessments were made of physical and chemical characteristics of the eggs. All treatments with added Spirulina increased unsaturated fatty acids and decreased saturated fatty acids with the largest responses for linolenic (omega 3) and oleic (omega 9) acids. The changes in fatty acids were greater with enriched than crude Spirulina. These results suggest that eggs from quail fed with Spirulina may have positive effects on human health.

Response surface methodology to investigate the comparison of two carbon-based air cathodes for bio-electrochemical systems.

Bio-electrochemical technologies can generate renewable electrical bioenergy from the oxidation of organic materials through the catalytic reactions of the microorganisms while treating the wastewater. In this study, the use of carbon aerogel as a novel catalyst with high porosity (the total pore volume of 1.84 cm3 g-1) and high surface area (491.7 m2/g) for improving the oxygen reduction reaction (ORR) performance was compared to that of the conventional activated carbon, employed as an air cathode catalyst in bio-electrochemical systems, with the indigenous bacterial consortium. The electrochemical studies revealed the higher power efficiency in the use of carbon aerogel (with the maximum power density and current density of a 675 mWm-2 and 33.1 mAm-2, respectively), compared to the activated carbon (with the maximum power density and current density of 668.98 mWm-2 and 23.2 mAm-2, respectively). The performance of the two materials and optimum conditions for electricity production were examined using the Response Surface Method (RSM) as an optimal design method. Statistical analysis confirmed that the carbon aerogel performed better than the activated carbon in power production and facilitated cathodic redox reactions. Comparison of two catalysts showed that the redox reactions occurred in the presence of carbon aerogel more facilitated and in a wider range, produced 1.2 times more current (the maximum 2.1 and 1.69 mA current). Carbon aerogel, with a suitable load absorbance and resistance to oxidation at urban wastewater pH, can be, therefore, coated on electrodes to facilitate the oxidation-reduction reactions and electricity transmission.

Promising Chemoprevention of Colonic Aberrant Crypt Foci by Portunus segnis Muscle and Shell Extracts in Azoxymethane-Induced Colorectal Cancer in Rats.

BACKGROUND AND PURPOSE: This study subjected a rat model to the extracts of muscle and shell tissues from Portunus segnis to assess their therapeutic effects on the HT-29 colon cancer cells as well as on colonic Aberrant Crypt Foci (ACF) induced by Azoxymethane (AOM). METHODS: The cell line was exposed to the extracts to compare the cytotoxicity of hexane, butanol, ethyl acetate, and water extract of muscle and ethanolic extract of the shell. Male rats (n=40) were assigned into control, positive, negative, and treatment groups. The animals were injected with AOM, except the control group, and then exposed to 250 and 500mg/kg of the crude extracts. Immunohistochemical localization of Bax and Bcl-2, as well as ACF and antioxidant enzymes, were evaluated in the rat colon. RESULTS: The butanolic muscle extract and ethanolic shell one demonstrated an IC50 of 9.02±0.19µg/ml and 20.23±0.27µg/ml towards the cell line, respectively. Dietary exposure inhibited the ACF formation and crypt multiplicity in the colon compared to the cancer control group. The activity of SOD and CAT increased, while that of MDA decreased. The expression of Bax and Bcl-2 increased and decreased, respectively. CONCLUSION: Taken together, the results show that both extractions were suggested to be suppressive to AOMinduced colon cancer.

Study of capability of nanostructured zero-valent iron and graphene oxide for bioremoval of trinitrophenol from wastewater in a bubble column bioreactor

BACKGROUND: Bioremoval of phenolic compounds using fungi and bacteria has been studied extensively; nevertheless, trinitrophenol bioremediation using modified Oscillatoria cyanobacteria has been barely studied in the literature. RESULTS: Among the effective parameters of bioremediation, algal concentration (3.18 g·L−1 ), trinitrophenol concentration (1301 mg·L−1 ), and reaction time (3.75 d) were screened by statistical analysis. Oscillatoria cyanobacteria were modified by starch/nZVI and starch/graphene oxide in a bubble column bioreactor, and their bioremoval efficiency was investigated. Modifiers, namely, starch/zero-valent iron and starch/GO, increased trinitrophenol bioremoval efficiency by more than 10% and 12%, respectively, as compared to the use of Oscillatoria cyanobacteria alone. Conclusions: It was found that starch/nano zero-valent iron and starch/GO could be applied to improve the removal rate of phenolic compounds from the aqueous solution.

Chemoprevention of Colonic Aberrant Crypt Foci by Novel Schiff Based Dichlorido(4-Methoxy-2-{[2-(Piperazin-4-Ium-1-Yl)Ethyl]Iminomethyl}Phenolate)Cd Complex in Azoxymethane-Induced Colorectal Cancer in Rats.

Schiff-based complexes as a source of cancer chemotherapeutic compounds have been subjected to the variety of anticancer studies. The in-vitro analysis confirmed the CdCl2(C14H21N3O2) complex possess cytotoxicity and apoptosis induction properties in colon cancer cells, so lead to investigate the inhibitory efficiency of the compound on colonic aberrant crypt foci (ACF). Five groups of adult male rats were used in this study: Vehicle, cancer control, positive control groups and the groups treated with 25 and 50 mg/kg of complex for 10 weeks. The rats in vehicle group were injected subcutaneously with 15 mg/kg of sterile normal saline once a week for 2 weeks and orally administered with 5% Tween-20 (5 ml/kg) for 10 weeks, other groups were injected subcutaneously with 15 mg/kg azoxymethane once a week for 2 weeks. The rats in positive groups were injected intra-peritoneally with 35 mg/kg 5-Flourouracil four times in a month. Administration of the complex suppressed total colonic ACF formation up to 73.4% (P < 0.05). The results also showed that treatment with the complex significantly reduced the level of malondialdehyde while increasing superoxide dismutase and catalase activities. Furthermore, the down-regulation of PCNA and Bcl2 and the up-regulation of Bax was confirmed by immunohistochemical staining.

Effects of three types of oil dispersants on biodegradation of dispersed crude oil in water surrounding two Persian gulf provinces.

OBJECTIVE: To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. METHODS: This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30°C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD) and chemical oxygen demand (COD) in microorganisms. RESULTS: The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P < 0.05). Mixture of oil and Pars 2 as well as oil and Pars 1 dispersants showed the highest BODs and CODs, respectively. In the Bahregan province, microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P < 0.05). CONCLUSION: Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from offshores with least secondary contamination should be investigated.

Comparison and influence of two newly produced Iranian oil dispersants (Pars1 &Pars2) with the Gamlen OD4000 on rainbow trout.

Dispersants are the group of chemicals, designed to be sprayed on to the oil slicks to accelerate the process of natural dispersion. In this study, the acute toxicity of two newly produced Iranian oil dispersants (Pars1 &Pars2) was evaluated and compared to the Gamlen OD 4000 in different concentrations on 28-32 g of rainbow trout (Oncorhynchus mykiss). The 50% of lethal concentration (LC50) of 96-h acute toxicity of exposed fish were determined by means of Probit value and ANOVA test. Relative effectiveness toxicity (RET) of all oil dispersants according to their LC50 has been measured. Pars1 has the lowest RET (12.56) in contrast to Pars2 (RET = 47.51) and Gamlen OD4000 (RET = 21.34) proved to have the highest efficiency and to be the best one under the laboratory conditions used in this study.