An approach for prioritizing “down-the-drain” chemicals used in the household

This article has been made available through the Brunel Open Access Publishing Fund.Many chemicals are present in cleaning and personal care products, which after use are washed down the drain and find their way into water bodies, where they may impact the environment. This study surveyed individuals to determine what products were used most in the home, in an attempt to prioritize which compounds may be of most concern. The survey resulted in the identification of 14 categories of products consisting of 315 specific brands. The survey estimated that individuals each discharge almost 33 L of products per year down the drain. Dishwashing liquids and hand wash gels, which accounted for 40% of this volume, were selected for identification of specific ingredients. Ingredients were classified as surfactants, preservatives, fragrances or miscellaneous, with hand wash gels having a wider range of ingredients than dishwashing liquids. A review of the literature suggested that preservatives, which are designed to be toxic, and fragrances, where data on toxicity are limited, should be prioritized. The approach undertaken has successfully estimated use and provisionally identified some classes of chemicals which may be of most concern when used in cleaning and personal care products

The most common laboratory procedures for the evaluation of EPB TBMs excavated material ecotoxicity in Italy: A review

The rapid development of the mechanized tunneling in current decades has raised serious concerns about the environmental impact of large quantities of the muck. EPB-TBMs require the use of foaming agents for optimizing the soil conditioning.These agents could contain some chemicals (e.g., sodium lauryl ether sulfate – SLES) that are not included in the current legislation at the Italian or EU level. In order to minimize the project costs, it is useful to re-use the excavated soil as a reusable by-product that requires that it does not have any environmental impact on the ecosystems. For this purpose, to draw up a site-specific protocol is a practical and successful tool to evaluate the environmental compatibility of excavated soil during the tunneling. It can rely on one-month experiments at a microcosm or mesocosm scale using soil coming from the excavated site.At fixed times (from 0 to 28 days) the chemical degradation of the chemical together with ecotoxicological tests can be performed on soil or soil-water extracts. Both aquatic and terrestrial organisms are used and the choice of the tests depends on the final destination site.The results of the residual concentration of SLES in soil and in the elutriates, together with those of the ecotoxicological tests, make it possible to evaluate the temporary storage of spoil material and the time necessary for obtaining a safe soil debris to be used as a by-product.These data are usually included in the site-specific protocol to be applied during the excavation phase.This paper describes the main methodological aspects regarding microcosm experiments

Germination, root elongation, and photosynthetic performance of plants exposed to sodium lauryl ether sulfate (SLES). An emerging contaminant

The anionic surfactant SLES (sodium lauryl ether sulfate) is an emerging contaminant, being the main component of foaming agents that are increasingly used by the tunnel construction industry. To fill the gap of knowledge about the potential SLES toxicity on plants, acute and chronic effects were assessed under controlled conditions. The acute ecotoxicological test was performed on Lepidum sativum L. (cress) and Zea mays L. (maize). Germination of both species was not affected by SLES in soil, even at concentrations (1200 mg kg−1) more than twice higher than the maximum realistic values found in contaminated debris, thus confirming the low acute SLES toxicity on terrestrial plants. The root elongation of the more sensitive species (cress) was instead reduced at the highest SLES concentration. In the chronic phytotoxicity experiment, photosynthesis of maize was downregulated, and the photosynthetic performance (PITOT) significantly reduced already under realistic exposures (360 mg kg−1), owing to the SLES ability to interfere with water and/or nutrients uptake by roots. However, such reduction was transient, likely due to the rapid biodegradation of the surfactant by the soil microbial community. Indeed, SLES amount decreased in soil more than 90% of the initial concentration in only 11 days. A significant reduction of the maximum photosynthetic capacity (Pnmax) was still evident at the end of the experiment, suggesting the persistence of negative SLES effects on plant growth and productivity. Overall results, although confirming the low phytotoxicity and high biodegradability of SLES in natural soils, highlight the importance of considering both acute and nonlethal stress effects to evaluate the environmental compatibility of soil containing SLES residues

Some Indian medicinal plants, their pharmacological action and synthesis of embelic Acid

From the earliest times medicine has been a curious blend of superstition, empiricism and of sagacious observation out of which ultimately science is made. Of these three strands, superstition, empiricism and observation, medicine was constituted in the days of the priest physicians of Egypt and Babylonia; of the same three strands it is still composed. The p r o p o r t i o n s have, however, varied significantly. An increasingly alert and determined effort, running through the ages, has endeavoured to expel superstition, to narrow the range of empiricism and to enlarge, refine and systematise the scope of observation. Superstition is easily recognisable, but the line between an empirical and scientific observation is not so clear. Empiricism does not endeavour to penetrate more deeply and gets no further. On the other hand a scientific observer is not content with mere facts; he asks the reasons and seeks to establish further relationships, while the empiricist practising his rule of thumb works disjointedly and tends to remain in reference to any particular observation just where he is. This difference between empiricism and a sustained scientific research of known facts in short is the subject of these investigations

Toothpaste formulation efficacy in reducing oral flora

Purpose: To assess the microbial quality as well as the effectiveness of seven brands of toothpaste marketed in Abuja, Nigeria's capital city, for reducing oral bacterial flora. Methods: Seven brands of toothpaste were randomly purchased from the open market in Abuja. Two brands contained triclosan + sodium fluoride as antibacterial, four contained sodium fluoride only and one was herbal. Each of the toothpaste products was assessed in duplicate for microbial safety based on growth on nutrient agar and broth. Also, eight volunteers were enrolled who used a toothpaste brand 12hourly on three consecutive occasions as the only source of oral hygiene, and then switched over to another brand. Mouth swaps and saliva before and after brushing was taken, plated by the pour plate technique, incubated at 37°C and then counted on nutrient agar after 24 h. Percentage bacterial reduction was calculated from the difference in bacterial counts before and after brushing. Results: All the toothpaste brands were sterile. 71% of the toothpaste brands were found to significantly (p=0.068) increase saliva bacteria counts. No brand of toothpaste removed teeth bacteria by up to 50%. On average, the two triclosan-containing toothpaste brands exerted a greater reduction in mouth bacteria than non-triclosan toothpaste brands. This was followed by the herbal toothpaste. The toothpaste brands that contained only fluoride were the least effective in reducing mouth bacteria. Conclusion: The results from our study indicate the need for further research into the possible value of toothpaste for reducing oral bacterial flora. Keywords: Tooth bacteria, Oral bacteria, Triclosan, Toothpaste, Fluoride, Natural toothpasteTropical Journal of Pharmaceutical Research Vol. 8 (1) 2009: pp. 71-7

QUANTIFYING MAGNETITE IN CHITOSAN MICROSPHERES LOADED WITH 5-FLUROURACIL USING MODIFIED COLORIMETRIC METHOD: A COMPARATIVE STUDY WITH THERMOGRAVIMETRIC ANALYSIS

Objective: The purpose of the present investigation is to develop a simple colorimetric estimation of magnetite from magnetic microspheres.Methods: Emulsification and cross-linking technique was used to prepare 5-fluorouracil loaded chitosan magnetic microspheres. The microspheres were evaluated using optical microscopy, scanning electron microscopy and X-ray diffraction. A modified colorimetric method was employed to determine magnetite content of chitosan microspheres with and without the drug. Microspheres were digested by HCl to convert magnetite into ferrous/ferric ions. Absorbance of yellow coloured complex of these ions with sulfosalicylic acid at alkaline pH was measured to quantify magnetite at 425 nm. The determination of magnetite by the colorimetry validated through a thermogravimetric analysis of the same samples.Results: The presences of magnetite in the microspheres were qualitatively confirmed by the photomicrograph, scanning electron microscopy, and X-ray diffraction studies. Colorimetric determination of magnetite content of the drug loaded, and unloaded chitosan microspheres were 21.5 and 20.6%w/w, respectively. The magnetite content of the same samples estimated by thermogravimetric analysis was 22.5 and 19.1%w/w, correspondingly, which were much closer to the colorimetric estimation. The drug loading in the microsphere was 12.35% w/w, and the X-ray diffraction analysis confirms amorphous nature of the loaded drug.Conclusion: The proposed colorimetric quantification of magnetite is simple cost-effective and could be useful in determining magnetite content of magnetically targeted drug-delivery systems.Â

Surfactants: Pharmaceutical and Medicinal Aspects

Surfactants are amphipathic substances with lyophobic and lyophilic groups and are critical components in pharmaceutical products. Surfactants have several uses in pharmaceuticals, i) for solubilisation of hydrophobic drugs in aqueous media, ii) as components of emulsions ,iii) surfactant self-assembly vehicles for oral and transdermal drug delivery, iv) as plasticizers in semisolid delivery systems, and v) as agents to improve drug absorption and penetration. Non-ionic surfactants such as ethers of fatty alcohols are most commonly used in pharmaceuticals. Cationic surfactants are capable of exerting antibacterial properties by disrupting bacterial cell membranes. In pharmaceutical processing, phospholipid lecithin, bile salts, certain fatty acids and their derivatives have become indispensable since they afford a uniquely effective and eficient mechanism of drug carriage by solubilising the drugs of fatty origin. The antibacterial, antifungal and antiviral activities make biosurfactants relevant molecules for applications in combating many diseases and as therapeutic agents. Biosurfactants have the potential for use as major immunomodulatory molecules, as anti-adhesive biological coating for biomaterials, in vaccines and gene therapy, and they may be incorporated into probiotic preparations to combat urogenetical tract infections and pulmonary immunotherapy. Gemini surfactants are effective potential transfection agents for non-viral gene therapy. Ionic liquids act as secondary surfactants and the use of surfactant/ionic liquid systems should be explored to build speciic properties in the organized medium, and to explore pharmaceutical applications of traditional, biosurfactant and Gemini surfactants

The refolding of recombinant human liver methylmalonyl-CoA mutase from inclusion bodies produced in Escherichia coli : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University

Human methylmalonyl-CoA mutase (hMCM) is an adenosylcobalamin-dependent enzyme that catalyses the structural rearrangement of (R)-methylmalonyl-CoA to succinyl-CoA as pan of the catabolism of the branched chain amino acids valine, leucine and isoleucine, odd chain fatty acids and intermediates of cholesterol metabolism. Reactions that require adenosylcobalamin (AdoCbl) have been intensively studied, and the first step in the catalysis is widely agreed to involve homolytic cleavage of the unusual carbon-cobalt bond in the cofactor. A reliable source of recombinant hMCM would be useful in defining more fully the mechanistic pathway of AdoCbl-dependent enzymes. Recombinant hMCM overexpressed in E. coli forms insoluble aggregates of inactive protein known as inclusion bodies. hMCM inclusion bodies were purified, solubilised and then several different in vitro refolding techniques were tested in attempts to produce active recombinant hMCM from purified solubilised inclusion body material. These methods included refolding by rapid dilution, refolding by dialysis, detergent-assisted refolding, refolding by gel filtration chromatography and chaperonin-assisted refolding. Chaperonin-assisted refolding necessitated the purification of recombinant E. coli chaperonins GroES and GroEL from the E. coli strain DH1/pGroESL. Refolding by rapid dilution of the GdmHCl-solubilised inclusion bodies into a refolding buffer was judged to be the simplest and most effective method, however the refolding process was extremely inefficient. Refolding by rapid dilution was scaled up to 2 litres to produce as much active hMCM as possible. The refolded protein was concentrated by batch adsorption to and stepwise elution from hydroxyapatite, and further purified using a synthesised 5'adenosylcobalamin- agarose 'affinity' chromatography column. The final refolded hMCM preparation contained a single ~29 kDa contaminant protein, tentatively identified as E. coli branched-chain amino acid aminotransferase (EC 2.6.1.42), present in approximately equal amounts to the hMCM, and had a specific activity of ~3.11 units/mg