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Revista de química analítica ambiental

Volumen 2, Asunto 3 (2015)

Artículo de investigación

Characterization of Prophenoloxidase in Resisting Adverse Stresses in Apis cerana cerana

Feng Liu, Pengbo Yao, Xulei Guo, Zhenguo Liu, Xingqi Guo and Baohua Xu

Insect prophenoloxidases (PPOs) are a group of important innate immunity proteins and play an important role in melanin synthesis, defending the intruding microorganisms and parasites, healing wound and cuticle pigmentation. However, there is little study about immune-related defense mechanisms in Apis cerana cerana. Here we isolated a PPO gene from A. cerana cerana and evaluated the connection of AccPPO to immunity. AccPPO has an open reading frame of 2079 bp encoding a 693 amino acid protein. The genomic structure analysis showed that AccPPO is similar to that of AmPPO. AccPPO is also close to AmPPO in the evolutionary period. AccPPO expression could be detected in all the developmental stages of A. cerana cerana and was the highest in 15-day postemergence adults. In addition, we also found that AccPPO was induced by the infection of Ascosphaera apis and various oxidative stresses including 4, 16°C; UV light; and pesticides (acaricide, cyhalothrin, paraquat) treatments. These results revealed that AccPPO may play a critical role in resisting Ascosphaera apis and preventing A. cerana cerana from oxidative stresses.

Artículo de investigación

Photo-Degradation of Amoxicillin, Streptomycin, Erythromycin and Ciprofloxacin by UV and UV/TiO2 Processes. Evaluation of Toxicity Changes Using a Respirometric Biosensor

Raffaella Palmisano, Luigi Campanella and Barbara Ambrosetti

Current research aims to conserve natural resources, especially water. Our study focuses on developing water purification to remove contaminating antibiotics using heterogeneous photo-catalysis. We compare photolysis with and without TiO2 catalysis, testing the photo-stability of four representative antibiotics: Amoxicillin, streptomycin, erythromycin and ciprofloxacin by HPLC using a Perkin Elmer 2000 chromatograph, BIO-RAD Bio-sil ODS-5S L 250 mm × 4 mm ID C18 reversed phase column and Perkin Elmer LC-90 UV detector. Both obeyed first order reaction kinetics, usually following the Lagmuir-Hinshelwood model. A respirometric biosensor was employed to assess the toxicity of drug solutions and photo-degradation products. We demonstrate that catalysis consistently decreases toxicity more effectively in all cases. The photo-degradation of ciprofloxacin and amoxicillin took longer.

Artículo de investigación

Heavy Metals Contamination in Vegetables and its Growing Soil

Tasrina RC, Rowshon A, Mustafizur AMR, Rafiqul I and MP Ali

Dietary exposure to several heavy metals including Ni, Cd, Cr, Co, Pb, As, Hg, Zn and Cu, has been recognized as a risk to human health through the consumption of vegetable crops. This study investigates the source and magnitude of heavy metal contamination in soil and various kinds of vegetables including potato, red amarantha, spinach, amarantha, carrot, cabbage, tomato and brinzal at Pakshi, Bangladesh is a mix of commercial and residential vegetables growing areas. The concentration of as and Fe in all soil sample tested is higher than that of permissible limit of different international standard. The concentration of Co in Chor Ruppur, Pb in Pakshi and Diarpur, Mn in Chor Rupupr and Zn in Chor Ruppur and Pakshi soil are also higher than that of standard level. Other tested metals are lower than that of standard level. The lead in vegetables in all tested areas was higher level than that of the permissible limits of different International standards. Except lead, it is concluded that nearly all the samples did not exceed the Intentional Food Standards maximum level (ML) in vegetables at Pakshi region in Bangladesh. If contaminated soil and vegetables contribute to a progressive gathering of these metals in food chain there might possible to deep alternations of ecosystem with possible noxious effect on human health. Our study highlights that vegetables growing soil containing higher amount of metals that could be transferred into edible parts of the plant, so study area should be monitored regularly to avoid health risk of human being due to exposure of toxic level.

Artículo de investigación

Application of Thermally and Chemically Modified Banana Peels Waste as Adsorbents for the Removal of Iron from Aqueous System

Yousaf MM and Sajjad

In the present study the potential of modified banana peels for the removal of total iron from aqueous system was investigated. Batch mode study was carried out. Isotherm data was generated and fitted in Langmuir and Freundlich equation to explain the phenomenon of adsorption. The adsorption capacities based on Langmuir model (Qm) of the 3 adsorbents were found to be 1.47 for raw banana peel (RP), 0.93 for the grafted peel (GP) and 1.8 mg/g for the Charred peel (CP). The R2 values were 0.99 for raw banana peel (RP), 0.93 for grafted peel (GP) and 0.96 for charred peel (CP). Based on Freundlich model the adsorption capacities (K) were 2.89, 2.78 and 3.95 mg/g for raw peel (RP), grafted peel (GP) and charred peel (CP). The R2 values were found to be 0.96, 0.94 and 0.95 for the raw banana peel (RP) grafted peel (GP) and charred peel (CP) respectively. Our results showed that modified banana peel products can be used as potential adsorbents for removal of iron from aqueous environment

Artículo de investigación

Determination of Toxic Metal Accumulation in Shrimps by Atomic Absorption Spectrometry (AAS)

Fatema K, Naher K, Choudhury TR, Islam MA, Tamim U, Hossain SM , Islam SMA and MP Ali

The study was carried out to assess the levels of lead (Pb), cadmium (Cd), arsenic (As), chromium (Cr), and mercury (Hg) in different shrimp species. Atomic absorption spectrometry was used to estimate and evaluate the levels of these metals from 11 shrimp samples. The results of this study showed that the average concentrations detected were ranged from <0.1 to 0.202, <0.1 to 0.416, <0.1 to 0.156, <0.1 to 0.21 and <0.1 to 0.28 mg/kg for Pb, Cd, As, Cr and Hg, respectively in river shrimps. In case of Gher, it was ranged from <0.1 to 0.267, <0.1 to 0.166, <0.1 to 0.156, <0.1 to 0.21 and <0.1 to 0.228 mg/kg for Pb, Cd, As, Cr and Hg, respectively. The results show that Pb concentration for both river and Gher samples lies between EU and IAEA limits, Cd concentration in river samples are higher than both EU and IAEA limits. Arsenic is observed only in one river sample that was also below the recommended level. Hg concentration for both Gher and river samples are less than the EU permissible limit. Our study highlights those toxic metals are found to be below the recommended tolerable levels in shrimp of Bangladesh and may not constitute a health hazards for consumers.

Artículo de investigación

Effect of Heating on the Color Formation Reaction in the Murphy and Riley Method for the Determination of Phosphate in Natural Waters

Su-Cheng Pai, Tzu-Yuan Wang, Tien-Hsi Fang and Kuo-Tung Jiann

Heating is frequently applied to enhance the reaction rate for the determination of phosphate but it may cause unexpected errors. Experiments show that the spectrum of the blue color produced by the Murphy and Riley method is subject to change at different temperatures. The variation of the molar extinction coefficient at 880 nm was found to be -48 M-1cm-1°C-1, or a relative trend of -0.22 % °C-1 w.r.t. to the absorbance at 30°C. When the color formation reaction took place at >35°C, the absorbance started to climb. At temperatures >60°C, the results were erratic and the change becomes irreversible. These findings suggest that the measurement should be made at room temperature and any heating process above 35°C should be avoided. A thermostated cuvette holder set at 30°C is highly recommended for both manual and flow type operation.

Artículo de investigación

Acute and Chronic Effects of Disturbance Control Factors, Complications and Treatment Method

Niyousha MR, Panahi Y and Golzari S

The main aim of this study was to collect the experiences of Iranian researchers about different types of tear gases and pepper sprays, effects, treatment strategies and also to provide a guideline for the prevention of abuse of these dangerous agents. Tear gases include CS, CN, CA and OC sprays most common of which is CS. Tear gas that through the eyes of confusion (tearing and spasm) of the eyelids and closing the gases, and through upper respiratory tract irritation (sneezing and vomiting) temporary disables the person. Pepper spray, also known as OC spray (from “oleoresin capsicum”), OC gas, and capsicum spray, is a lachrymatory agent (a chemical compound that irritates the eyes to cause tears, pain, and temporary blindness). It is used in policing, riot control, crowd control, and personal self-defense, including defense against dogs and bears. Its inflammatory effects cause the eyes to swell, impairing the vision. The results also show that tear gas abstract by target tissues of the eyes, skin, and digestive system and affect the nerves. There is no effective antidote to common tear gases; however, decontamination is the first line of action. Once a person exposed to these agents, there is a variety of methods to remove as much chemical as possible and relieve the symptoms. The standard first aid for burning solutions in the eye is irrigation (spraying or flushing out) with water, and some evidence suggests that diphoterine solution, a first aid product for chemical sprays, may help with ocular burns or chemicals in the eye. As chemical gases are easily accessible and the risk of their being used threatens people, the proposed approach is necessary to control all gases. It is suggested that these gases and sprays be less available and less used. Furthermore, the proper administration route of these tools should be taught to people.

Artículo de investigación

Energy Regulation in the EKC Model with a Dampening Effect

Agustín Alvarez-Herranz and Daniel Balsalobre-Lorente

The empirical environmental kuznets curve (EKC) model provides a popular means to analyze the correlation between economic growth and environmental destruction. This study seeks to verify if implementing environmental regulations has effects beyond the EKC. An elaborated panel data model applies to 28 OECD countries to analyze not only the relationship between economic growth and environmental destruction but also the effect of regulatory activities on the replacement of energy sources and their efficiency. The proposed model also accounts, for the first time, for the effect of level of income on the replacement of energy sources. Using the EKC, this study demonstrates that energy regulation measures help reduce greenhouse gas emissions (GHG). To validate this hypothesis, we have also added the dampening effect that income level has over the contribution of renewable energy sources to the total of energy consumption. The estimation reveals increases in the explanatory power of the model. This study concludes that pollution will not disappear automatically when economic growth increases. Therefore the need to develop energy efficiency RD&D in order to reduce environmental pollution.

Artículo de investigación

Parametric Study for Adsorption of Sodium Rhodizonate on Chitosan

Kanwal Rashid, Ayesha Saddiqa and Arfa Nawaz

Sodium Rhodizonate, a derivative of Rhodizonic acid is widely used in industry and also for detection of different metals in waste water. In the present work the ability to remove Sodium Rhodizonate from waste water is studied using Chitosan as an adsorbent material. The studies are approved as a function of adsorbent amount, contact time, pH and temperature. Acidic pH (1.5-2), medium temperature (45-55) were found to be favorable for adsorption of Sodium Rhodizonate. Maximum adsorption of chitosan is obtained after 70 minute. Similarly the initial concentration Equilibrium isotherm was measured experimentally at different temperatures. It has been constructally shown that chitosan is a highly promising material for the removal of Sodium Rhodizonate

Artículo de investigación

Removal of Abamectin Pesticide by Electrocoagulation Process Using Stainless Steel and Iron Electrodes

Ghalwa A, Nasser M and Farhat NB

In this work the removal efficiency of abamectin and chemical oxygen demand (COD) from aqueous solution using the electrocoagulation process were investigated. The effects of operational parameters such as initial pH, initial abamectin concentration, current density, type electrolyte, salt concentration, and temperature on the pesticide and COD removal efficiency have been studied. With an initial pH of 3.7, an initial pesticide concentration of 150 mg/L, (current density 87.5 mA/cm2 and 50 mA/cm2 for stainless steel (SS) and iron (Fe) electrodes respectively), salt concentration of 1 g/L and temperature of 30°C, the results showed that abamectin and COD removal were 94% and 76.9% by using SS and were 64.5% and 50%, by using Fe electrodes. Pesticide removal kinetic followed pseudo first and second order kinetics using SS and Fe electrodes respectively. It can be concluded that electrocoagulation process by SS electrode is very efficient and clean process for abamectin removal and COD from wastewater.

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