High Chloride Levels Research Articles

Effects of ammonia toxicity on growth performance, cortisol, glucose and hematological response of Nile Tilapia (Oreochromis niloticus)

Ammonia is a production limiting factor in the aquaculture media affecting fish production. A study was designed to scrutinize effects of ammonia on growth performance, survival, cortisol and hematological parameters of Tilapia fish. The study examined effects of 96 h-incubation of male and female Tilapia with 3 mg ammonium chloride per a liter of water compared to control. The study has been carried out in the physiology laboratory of the department of animal and fish production, Alexandria University. Fourteen aquaria were used (6 control and 8 ammoniated). Each aquarium contained 6 fish (half the population males and the other have females). Duration of the control reared fish was 30 days, however the duration for ammoniated group was 4 days. In all stressed fish, there found decreases in final body weight, average daily gain and specific growth rate as compared to controls. Hematological parameters revealed increases (P0.05) in total leukocyte counts in both males and females exposed to stressors. There were significant decreases (P0.05) in red blood cell, hematocrit value and hemoglobin concentration in both males and females. There were non-significant differences (P0.10) in these parameters between males and females. Exposing both male and female tilapia to ammonia, resulted in increases (P0.05) in mean corpuscular volume (MCV). Mean corpuscular hemoglobin (MCH) didn’t change in male tilapia, while females expressed increased MCH values in the ammonia condition. Mean corpuscular hemoglobin concentration (MCHC) decreased (P0.05) under ammonia with no differences between males and females. Differential leukocyte count exhibited increases (P0.05) in neutrophils in ammonia-exposed males and females and decreases (P0.05) in eosinophils and monocytes in males, but not in females. However, lymphocytes decreased (P0.05) in both females and males exposed to ammonia. Cortisol level increased (P0.05) by about 2 folds in both sexes of fish exposed to ammonia (2.95 and 2.72 vs6.40 and 6.48 ng/ml in control males and females vs ammonia-exposed males and females).Rearing tilapia fish in media containing high level (3mg/l water) of ammonium chloride not only deteriorated growth rate but it also negatively affected the health wellbeing.

Influence of chloride and moisture content on steel rebar corrosion in concrete

Reinforced mortar samples were exposed in humidity chambers with different relative humidity or exposed in cyclic moisture conditions. The rebars were in an “as received” condition meaning that the preexisting oxide scale were intact. The lowest chloride concentration that initiated corrosion was 1% Cl− by mass of cement, corrosion was then observed for samples exposed at 97% relative humidity. It is suggested that the corrosion rate decreases when samples are exposed to a relative humidity lower than 97%. The results indicate that threshold levels should be evaluated at rather humid conditions (97%) despite the fact that the maximum corrosion rate at higher chloride levels is observed in the interval 91–94%. For samples exposed to cyclic moisture conditions, a lower chloride concentration was needed to initiate corrosion compared to samples exposed in static moisture conditions.

Performance and Acceptance of Novel Silver-Impregnated Ceramic Cubes for Drinking Water Treatment in Two Field Sites: Limpopo Province, South Africa and Dodoma Region, Tanzania

Diarrheal disease and environmental enteropathy are serious public health concerns in low-income countries. In an effort to reduce enteric infection, researchers at the University of Virginia developed a new point-of-use (POU) water treatment technology composed of silver-impregnated porous ceramic media. The ceramic is placed in a 15 L plastic container of water in the evening and the water is ready to drink in the morning. The purpose of this study was to assess field performance and local acceptance of technology in two communities in Limpopo Province, South Africa, and one community in Dodoma Region, Tanzania. Performance was determined by coliform testing of treated water. Acceptance was determined using data from 150 household surveys and a nine-day structured observational study at a local primary school. At the primary school, 100% of treated water samples had no detectable levels of total coliform bacteria (TCB) in buckets filled by researchers. For all treated school buckets, 74% of samples achieved less than or equal to 1 CFU/100 mL and 3.2 average log reduction of TCB. Laboratory experiments with highly contaminated water diluted to lower turbidity achieved 4.2 average log reduction of TCB. Turbid water (approximately 10 NTU) only achieved 1.1 average log reduction of TCB; turbidity and organic material may have interfered with disinfection. The Tanzania primary school (deep groundwater source) had less turbid water and achieved 1.4 average log reduction of TCB; however, it did have high chloride levels that may have interfered with silver disinfection. The surveys revealed that the majority of people retrieve, store, and dispense water in ways that are compatible with the new technology. The willingness-to-pay study revealed potential customers would be willing to pay for the technology without subsidies. The results of this study indicate that this novel silver-impregnated ceramic POU water treatment technology is both effective and appropriate for use in the study communities.

Multivariate Classification of Original and Fake Perfumes by Ion Analysis and Ethanol Content.

The increased marketing of fake perfumes has encouraged us to investigate how to identify such products by their chemical characteristics and multivariate analysis. The aim of this study was to present an alternative approach to distinguish original from fake perfumes by means of the investigation of sodium, potassium, chloride ions, and ethanol contents by chemometric tools. For this, 50 perfumes were used (25 original and 25 counterfeit) for the analysis of ions (ion chromatography) and ethanol (gas chromatography). The results demonstrated that the fake perfume had low levels of ethanol and high levels of chloride compared to the original product. The data were treated by chemometric tools such as principal component analysis and linear discriminant analysis. This study proved that the analysis of ethanol is an effective method of distinguishing original from the fake products, and it may potentially be used to assist legal authorities in such cases.

An insight into the drinking-water access in the health institutions at the Saharawi refugee camps in Tindouf (Algeria) after 40 years of conflict

Drinking water access in the Saharawi refugee camps located in the Algerian desert is a challenge that is still an on-going problem after 40years of conflict. This work presents an analysis of the situation with emphasis on the water supply in health institutions (quantity and quality) including both sanitary inspections and a comprehensive water quality study. Results from sanitary inspections show that only half of the water supply installations at the hospitals are in adequate conditions and the rest present high risk of microbiological contamination. Water access in small medical community centres on the other hand present issues related to the non-availability of food-grade water tanks for the institutions (70%), the use of small 10l containers as the main water supply (40%), poor maintenance (60% under antihygienic conditions and 30% with damaged covers), and insufficient chlorine levels that prevent microbiological contamination. Regarding water quality analyses, raw water supply in Smara, El Aiun and Awserd camps present high conductivity and high levels of fluoride, chloride, nitrate and sulphate, but dropping to normal levels within the drinking-water standards after water treatment via reverse osmosis plants. But for the case of El Aiun and Awserd, the reverse osmosis plant only provides treated water to the population each 20days, so the population receives raw water directly and health risks should be evaluated. Finally, Dakhla water supply is the best in terms of physico-chemical parameters quality, currently providing safe drinking water after a chlorination stage. In summary, drinking water access has improved dramatically in the last years due to the efforts of local and international authorities but several issues remain to be solved: access to treated water for all the population, improved water quality controls (especially in Dakhla), expansion of distribution networks, and adequate storage systems and maintenance.

Physicochemical quality of groundwater and pollution risk in arid areas: the case of Algerian Sahara

In urban areas, population growth generates significant amounts of wastewater which are treated in specialized treatment stations or rejected directly without control in the case of short water Bechar River. Because of their diverse backgrounds, these waters are often loaded with organic elements, minerals, and microorganisms; some of which could be harmful to health and is heavily involved in the degradation of groundwater that may be irreversible. The study was conducted on two boreholes located next to the Bechar River (north and south) by influencing wastewater localized on the course of the Bechar River. A work plan has been adopted; it is early to make a monthly monitoring of two wells during the period from January 2007 to April 2014, with a comprehensive analysis of physicochemical parameters, to determine the various anthropogenic contributions to polluting nature in the region and analyze their physicochemical composition, to explain the origin and evolution of each element. The analyses revealed the levels of Cl, NO3, NO2, NH4, and phosphates that can be passed to the groundwater by the water surface runoff of the river; the wastewater undergoes a slow percolation through the layers Triassic. This is confirmed by the high levels of chlorides, ranging from 180 mg/l in 2007 to 216 mg/l in 2014 for drilling north and 199 to 336 mg/l for drilling south of the river, which explains the values of the conductivity of 990 μS/cm ranging up to 1050 μS/cm. Nitrate concentrations ranged from 11 mg/l to 28 mg/l for the drilling located north of the river.

Efficient Bi-Functional Electrocatalysts of Strontium Iron Oxy-Halides for Oxygen Evolution and Reduction Reactions in Alkaline Media

Strontium iron oxyhalide perovskitic oxides were investigated by electrochemical characterization as bi-functional electrocatalysts for oxygen evolution (OE) and oxygen reduction (OR) reactions in alkaline media. The electrochemical investigations showed that the presence of lower levels of oxygen and higher levels of chloride, as in Sr4Fe3O8Cl2 and Sr2FeO2Cl2 significantly enhanced the oxygen evolution and reduction over the other perovskitic oxides. Additionally, Sr4Fe3O8Cl2 and Sr2FeO2Cl2 was proven to have high bi-functional activity due to an overpotential gap (ΔE = 0.70 V) between the OER and ORR much lower than that of other similar perovskite bi-functional catalysts. In comparison with other strontium iron oxyhalide based electrocatalysts, Sr2FeO2Cl2 was shown to have higher OER activities among all investigated catalysts. This work demonstrates that the oxygen-deficient layered perovskites of the type A2BO2X2 are a new class of high-performance electrocatalysts for oxygen evolution (OE) and oxygen reduction (OR) reactions in alkaline media.

Impacts of soil-soluble anions on wild and cultivated herbaceous species: implications for soil phytoremediation

This study addresses the growing problem of soil salinity. In Mediterranean regions, disused solid waste landfills have given rise to disturbed ecosystems. At such sites, both mobile soil anions and cations have toxic effects on plants. Thus, detailed knowledge of these effects is needed for the phytoremediation of soils facing the problem of salinization. In this study, high chloride levels were detected in soil samples from several sealed waste landfill sites showing metal pollution. We also examined the nutrition behaviour of six native and five cultivated herbaceous species (two forage species and three for human consumption) grown in soils containing zinc chloride. Based on the tolerance shown by Lolium rigidum to this salt in a first bioassay, we assessed its behaviour in the presence of other chlorides and other Zn salts (sulphates and nitrites). Besides providing plant anion concentrations (which are particulary novel results), our study identified Lolium rigidum as a species able to well-tolerate soil salinity and accumulate high levels of zinc chloride indicating its possible use for the phytostabilization of soils polluted with this salt.

Spurious Hyperchloremia and Negative Anion Gap in a Child with Refractory Epilepsy.

We report a case with spurious hyperchloremia with negative anion gap in a child who was taking potassium bromide for refractory epilepsy. Blood chemistry showed a high chloride level (171 mEq/L) and a negative anion gap (−52 mEq/L). Plasma chloride concentration is measured by an ion-selective electrode method; however the presence of other anions like bromide and iodides can interfere with chloride level and largely overestimates the chloride concentration. Thus hyperchloremia with a negative anion gap is a clue to the diagnosis of halides like bromide and iodide ingestion.

Enhanced AOX accumulation and aquatic toxicity during 2,4,6-trichlorophenol degradation in a Co(II)/peroxymonosulfate/Cl⁻ system.

Chloride ion is known to affect on degradation kinetics in different ways during HO· and SO4(·-)-based advanced oxidation processes (AOPs). However, its effect on absorbable organic halogen (AOX) evolution and acute toxicity of treated water remains unknown, despite the importance of the two parameters in evaluating the applicability of AOPs. In the present study, Co/peroxymonosulfate (Co/PMS) and UV/hydrogen peroxide (UV/H2O2) treatment of 2,4,6-trichlorophenol was compared in terms of AOX formation, chlorinated byproducts and acute toxicity. Both Co/PMS and UV/H2O2 systems were more reactive under acidic conditions, resulting in elevated AOX levels when compared with those at neutral pH. The presence of high levels of chloride led to an accumulation and increase of AOX in the Co/PMS system. The toxicity of chlorinated byproducts was evaluated using Photobacterium phosphoreum, and the results revealed a sharp increase in acute toxicity of Co/PMS reaction solutions on addition of chloride ion. However, addition of Cl(-) had no apparent impact on AOX and toxicity of UV/H2O2 reaction solutions. These findings may have significant technical implications for selecting feasible technologies to treat high salinity wastewater.

Development of a sensory tool to assess overall liking for the fatty, salty and sweet sensations

Understanding the origin of the overconsumption of too high levels of sucrose, sodium chloride and lipids in foods raises the question of the influence of the hedonics for these sensations. To better understand this relationship, a sensory tool that enables measurement of liking towards sweet, salty or fatty sensations is required. This liking towards a sensation has to be understood as an overall attractiveness of the sensation. Instruments already existing were unsatisfactory as including a limited number of foods not representative of the overall sensation.A set of hedonic tests, named PrefSens, was developed to measure an overall liking for fatty, salty or sweet sensations. Each test consisted in the rating on a 9-point hedonic scale of a food product at 5 different levels of lipids, sodium chloride or sucrose. To build the PrefSens test, a total of 144 food ranges were tested during the development step (n=341 subjects) including various food categories, matrices and serving temperatures. Then, based on the technical feasibility and ability to discriminate, 32 food ranges were selected (10 for fatty, 10 for salty and 12 for sweet). The perceived intensity of fatty, salty or sweet “sensations” of these selected foods was evaluated by a trained panel (n=12) using Spectrum® scales. During the application study, the hedonic evaluation of the selected foods was assessed in 6 tasting sessions by 567 subjects over 8 laboratories spread out in France. For each subject and each product, hedonic ratings (y) were fitted versus the level of fatty, sweet or salty (x) in a quadratic regression, from which the predicted optimal level (Lpref) was derived based on the x-coordinate of the parabola’s maximum weighted by the correlation coefficient between observed and predicted data. The overall liking score for fatty, salty or sweet sensations was the average Lpref over the compounding food ranges.The sensory profile showed that within each sensation the mean perceived intensity significantly increased in a linear manner with the nutrient level. An exception was for the two lowest levels of lipids which were not significantly perceived differently. Concomitantly, the overall liking scores followed an inverted U-shape centered on the middle level of lipids, sodium chloride or sucrose. The distribution was close to normality. Internal validity and consistency of the items compounding the sensations of fatty, salty or sweet were demonstrated. PrefSens is an internally valid and original tool that can be applied to a population sample in order to better understand the determinants of dietary behaviors.

Eutectic Freeze Crystallization process for the treatment of ternary textile wastewater concentrates

Textile wastewaters contain high levels of sodium chloride (NaCl) and sulphate (Na2SO4) salts. Conventional water treatment uses evaporative crystallization (EC) which is an energy intensive process and is only effective in recovering pure water and a mixed sulphate-chloride salt. The mixed salt is contaminated with hardness and colour and cannot be recycled within the plant. This research investigates the technical applicability of using Eutectic Freeze Crystallization (EFC) in the recovery of water (as ice) and Na2SO4 salt. The effect of varying the operating temperature on the recovery and the purity of the ice and the salt was investigated using a synthetic textile wastewater stream containing 1.4 wt% Na2SO4 and 4.5 wt% NaCl. Thermodynamic modelling software predicted that the nucleation temperature of ice and Na2SO4 to be -3.1 oC and for NaCl, -21.6 oC. The recovery of ice was predicted to be 49% and 79% for Na2SO4.10H2O at -6.5 oC. Experimental validation, limited to operating temperatures above -7oC, showed a cumulative recovery of 42 % of ice with 94 % purity and 51.3 % recovery with 98 % purity for Na2SO4.10H2O at -6.5 oC. Sulphate analysis of the residual mother liquor at this temperature showed that 8.6 g of Na2SO4.10H2O was entrapped within ice crystals, thus reducing the recovery of Na2SO4.10H2O and the purity of ice. EFC is technically applicable for the recovery of ice and a single salt in a ternary system, however separation of the two phases is problematic due to high ice formation. The stream should first be treated with multistage Reverse Osmosis before EFC, so as to concentrate the stream and reduce ice formation.

NKCC1 downregulation induces hyperpolarizing shift of GABA responsiveness at near term fetal stages in rat cultured dorsal root ganglion neurons.

BackgroundGABAA receptor-mediated neurotransmission is greatly influenced by cation-chloride cotransporter activity during developmental stages. In embryonic neurons Na–K–2Cl (NKCC1) cotransporters mediate active chloride uptake, thus increasing the intracellular chloride concentration associated with GABA-induced depolarization. At fetal stages near term, oxytocin-induced NKCC1 downregulation has been implicated in the developmental shift from depolarizing to hyperpolarizing GABA action. Mature dorsal root ganglion neurons (DRGN), however, express high NKCC1 levels and maintain high intracellular chloride levels with consequent GABA-induced depolarization.ResultsGramicidin-perforated patch-clamp recordings were used to assess the developmental change in chloride homeostasis in rat cultured small DRGN at the embryonic day 16 (E16) and 19 (E19). The results were compared to data previously obtained in fetal DRGN at E14 and in mature cells. A significant NKCC1 downregulation, leading to reduction in excitatory GABAergic transmission, was observed at E16 and E19.ConclusionThese results indicate that NKCC1 activity transiently decreases in DRGN at fetal stages near term. This developmental shift in GABAergic transmission may contribute to fetal analgesia and neuroprotection at birth.

Simultaneous Recovery of Potassium, Chloride and Removal of COD from Landfill Leachate Concentrates Using a Combination of Cation-Exchange Membrane Electrolysis

Nanofiltration (NF) and reverse osmosis (RO) filtration system are widely used in landfill sites as polishing step for advanced treatment of landfill leachates. The membrane systems always generate large amount of concentrates containing high level of refractory organic compounds, potassium, chloride and other inorganics, which hardly be treated via conventional biological process. Thus, a proper disposal of these concentrates from or RO systems is critically important.The advanced oxidation processes (e.g, electrochemical oxidation, Fenton oxidation and ozone oxidation) are generally used in treatment of the concentrates. However, the potential resource such as K+and chloride in concentrates are not efficiently recycled but discharged to environment. In present study, we explore innovative and environmentally sustainable treatment processes, a combined cation-exchange membrane electrolysis (CEME)/magnesium potassium phosphate (MPP) crystallization process, for treating NF concentrate, which include (a) contaminant removal: organic pollutant and ammoniacal-nitrogen removal; (b) recycling and onsite reuse of chloride ions in the form of gaseous chlorine; (c) separation and beneficial recovery of potassium from NF concentrates. This study demonstrated that the proposed combined process can effectively remove 82%, 99%, 34%, 99% of organic matter, ammoniacal-nitrogen, total nitrogen, and chloride ions, respectively. And the recovered gaseous chlorine was reused on site as a decolorizing agent for synthetic dye (RhB) containing wastewater and complete decolorization was also achieved. The potassium ions were recovered via magnesium potassium phosphate crystallization . Additionly, about 53% of the potassium (from 2762 mg/L to 1389 mg/L) was removed via formation of magnesium potassium phosphate(MgKPO4·6H2O) precipitate. A combination of membrane electrolysis process is demonstrated to be an effective method for the convenient recycling of NF concentrates generated from a landfill plant. This combined process achieves effective removal of organic pollutants in the concentrates and complete removal of NH3-N via an active chlorine-mediated reaction. The combined process also simultaneously enables highly efficient recycling of chloride and potassium ions from NF concentrates as beneficial products (gaseous chlorine and MgKPO4·6H2O buffered fertilizer, respectively). Additionally, we have demonstrated that the recovered gaseous chlorine could be reused on site as a decolorizing agent for treating colored wastewater (i.e., RhB solution), and that complete decolorization could be achieved. The results indicates that recycling of NF concentrate via the combination process is feasible. Figure 1

Fibrosis quística: detección bioquímica y diagnóstico molecular

Cystic fibrosis is the most severe common autosomal recessive disease in caucasian population. Its prevalence in countries of Western Europe is one case in 2.000-6.000 live births. Patients develop a chronic, progressive lung disease, which is the most common cause of morbidity and mortality. In 85% of cases there is also pancreatic insufficiency. Hepatobiliary and genitourinary disorders and azoospermia are frequent, although lung symptoms and pancreatic insufficiency determine the severity of the disease. It is a genetic disease caused by defects in the CFTR gene (Cystic Fibrosis Transmembrane Conductance Regulator). To date more than 1900 mutations have been reported. Diagnosis of the disease is essentially clinical and confirmation is made by the detection of high levels of sweat chloride and the identification of mutations in the CFTR gene.

A Case Study: Corrosion Failure of Tube Heat Exchanger

A failed heat exchanger was sent to CMRDI to investigate the possible causes of leaks occurred in the tubes of the heat exchanger. The heat exchanger tubes were made of stainless steel 316 straight type. The heat exchanger served to heat up water basin (desalinated water) during the cold winter time. The water contains a high chloride level. Corrosion testing indicated susceptibility towards pitting corrosion especially at high temperature. It was suggested that controlling chloride level and proper adjustment of pH are the optimum solutions to avoid corrosion of heat exchanger pipes.

Physicochemical Characteristics of Water Samples Collected from River Sokoto, Northwestern Nigeria

Physicochemical parameters of surface water collected from six different points (P1 to P6) on River Sokoto were analysed during January (Dry Season) and August (Rainy Season), 2014 to determine its water quality using standard methods. The highest temperature of 25.6&#176C was recorded by P1 in dry season while P5 recorded the highest value of 29.2&#176C in rainy season. All the water samples were alkaline in dry season with the highest pH value of 8.50 in P5 and the least value of 8.02 in P6 whereas in rainy season, P1, P2 and P3 were slightly acidic while P5 and P6 were slightly neutral and P4 alkaline. The highest values of 510 μS/cm and 850.3 mg/l were recorded from P4 for electrical conductance and hardness respectively in the rainy season whereas in dry season, P5 and P4 had the highest values of 321 μS/cm and 282.8 mg/l respectively. The highest DO and BOD levels in dry season were 1.7 mg/l and 0.7 mg/l respectively in P1 and the least values were 0.7 mg/l and 0.2 mg/l respectively in P5. But in the rainy season, P6 recorded the highest DO value of 0.1 mg/l while P2 and P5 recorded the least value of 0.07 mg/l. For BOD, P5 had the highest value (2.13 mg/l) while P3 had the least value (0.20 mg/l). For COD, the highest value (230 mg/l) was found in P4 and P6 and the least value (30 mg/l) was found in P1 in dry season while in the rainy season, P2 had the highest COD value (1008 mg/l) and P4 had the least value of 32 mg/l. TDS and TSS values generally were higher in the rainy season than in the dry season due to higher amount of floating particles in the rainy season. While P1 and P6 recorded the highest values (800 mg/l and 700 mg/l respectively) in the rainy season, P4 recorded the least value of 100 mg/l in both seasons. The highest Chloride level was found in P4 in the dry (100 mg/l) and rainy (180 mg/l) seasons with the least level in P2 (35 mg/l) in dry season and in P1 and P2 with the least level of 60 mg/l in the rainy season. The highest concentration of Sulphate in P1 (220 mg/l) in dry season was far above the highest concentration (124 mg/l) in the rainy season whereas highest concentration of Nitrate in dry season in P1 (19.7 mg/l) was somehow below the highest concentration in rainy season in P4 (28.1 mg/l). Phosphate and Ammonia had the highest values of 1.77 mg/l and 0.84 mg/l respectively in P5 in dry season while in rainy season, P6 and P4 had the highest values of 0.22 mg/l and 1.20 mg/l respectively. There was significant seasonal variation in some physicochemical parameters and most of the parameters were within permissible limits, thus, making the water suitable for irrigation purposes.

Ichthyofaunal Diversity and Water Quality in the Kangsabati Reservoir, West Bengal, India

The ichthyofauna in relation to water quality was studied on monthly basis from March, 2010 to February, 2011 in the Kangsabati Reservoir, West Bengal. The study revealed that physicochemical parameters of Kangsabati Reservoir were congenial for 39 fish species of commercial importance, belonging to 7 orders, 15 families, and 26 genera. The Cypriniformes were dominant with 17 species, followed by Siluriformes and Perciformes, with 7 species each, Channiformes with 3 species, Osteoglossiformes and Synbranchiformes with 2 species each, and Anguilliformes with 1 species. Regarding their conservation status, 27 species were of least concern, 1 species was vulnerable, 6 species were near threatened, 1 species was data deficient, and 4 species were not evaluated (IUCN-Version 2014.1). Economical values have also been evaluated. Water parameters such as temperature, pH, alkalinity, dissolved oxygen, hardness, free CO2, salinity, total inorganic nitrogen, and phosphate were recorded and found suitable for fish production. Conductivity, transparency, and high chloride level are minor limiting factor that may needs rectification for improved fisheries management.

Effect of traditional food preservatives on biofilm formation by food pathogens

Aims: This study investigated the effect of food preservatives on biofilm formation by food pathogens Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Methodology and results: Foodborne pathogens isolated from spices mix were analyzed for their resistance and biofilm formation in presence of certain traditional food preservatives. Sensitivity of pathogens against traditional preservative were tested by agar well diffusion method and agar dilution method. Biofilms growth were measured by crystal violet staining and distaining followed by absorbance at 563 nm. Biofilms were observed under electron microscope. P. aeruginosa was found to grow in Brain Heart Infusion broth supplemented with 7% ginger; similarly, E. coli and S. aureus also exhibited resistance to high level of garlic and sodium chloride, respectively. Although these pathogens belong to different classes e.g. S. aureus is a Gram-positive whereas E. coli and P. aeruginosa are Gramnegative. However, they employed similar strategy to nullify the toxic effect of food preservatives. During survival, these pathogens were found to change their living pattern from planktonic to biofilm mode of growth. Conclusion, significance and impact study: This study revealed that presence of resistant pathogens in food could nullify the impact of traditional food preservatives. The biofilm formation by pathogens could be potential hazard in traditionally preserved foods.

Decreased capacity for sodium export out of Arabidopsis chloroplasts impairs salt tolerance, photosynthesis and plant performance

Salt stress is a widespread phenomenon, limiting plant performance in large areas around the world. Although various types of plant sodium/proton antiporters have been characterized, the physiological function of NHD1 from Arabidopsis thaliana has not been elucidated in detail so far. Here we report that the NHD1-GFP fusion protein localizes to the chloroplast envelope. Heterologous expression of AtNHD1 was sufficient to complement a salt-sensitive Escherichia coli mutant lacking its endogenous sodium/proton exchangers. Transport competence of NHD1 was confirmed using recombinant, highly purified carrier protein reconstituted into proteoliposomes, proving Na(+) /H(+) antiport. In planta NHD1 expression was found to be highest in mature and senescent leaves but was not induced by sodium chloride application. When compared to wild-type controls, nhd1 T-DNA insertion mutants showed decreased biomasses and lower chlorophyll levels after sodium feeding. Interestingly, if grown on sand and supplemented with high sodium chloride, nhd1 mutants exhibited leaf tissue Na(+) levels similar to those of wild-type plants, but the Na(+) content of chloroplasts increased significantly. These high sodium levels in mutant chloroplasts resulted in markedly impaired photosynthetic performance as revealed by a lower quantum yield of photosystem II and increased non-photochemical quenching. Moreover, high Na(+) levels might hamper activity of the plastidic bile acid/sodium symporter family protein 2 (BASS2). The resulting pyruvate deficiency might cause the observed decreased phenylalanine levels in the nhd1 mutants due to lack of precursors.