Prediction of Gas Chromatographic Retention Times of Polychlorinated Biphenyls

Bogdan Bogdanov and Liljana Popovska

Two theoretical models of the relationship between the molecular structure of polychlorinated biphenyls (PCBs) and their gas chromatographic retention characteristics have been developed . The retention time of these compounds was predicted as a linear relationship between the retention times and 3D Wiener number with R of 0.990. A five-variable regression equation with R2 of 0.997 and relative standard deviation of 1.04% was developed. Descriptors that represent 3D Wiener number, degree of chlorination and a subclass of the nonvalent and valent molecular connectivity path, cluster and /or path/cluster type indices were among the variables included in the equation. Twenty-one commercially available PCBs are enough in order to accurately predict the retention times of all 209 PCB congeners.

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Geochemistry of Carcinogenic Trace Elements (Ni, Cr, Co) in and around Salem Magnesite Mine Area, Salem District, Tamil Nadu

M. Sathyanarayanan and P. Periakali

Fifty-five groundwater samples were collected in and around Salem magnesite mine area, Salem district, Tamil Nadu and analysed for major and carcinogenic trace elements (Ni, Cr, Co) which show that the quality of groundwater is not suitable for domestic use with some exception. The observed high concentration of hexavalent chromium at some sites requires immediate attention. Analytical results of Ni, Cr and Co in soil and rock samples indicate that lateritic weathering in the upper weathered and decomposed/disintegrated rock appears to have mobilised and depleted these trace elements from the mine overburden and ultrabasic rocks enriching the same in groundwater.

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Synthesis Of 2, 3 Dihydro-1H -Naphtho [2, 1-B] Pyrane -1-one Semicarbazone and Selective Extraction of Palladium (II) Metal

Avinash B. Chaudhary, S . Nirupa and R. S. Lokhande

2,3 dihydro-1H-naphtho [ 2, 1-B ] pyrane-1-one semicarbazone (DNPS) was synthesized and its characterization study was carried out using elemental analysis, IR and NMR techniques. The reagent was proposed as extractant for development of new extractive spectrophotometric method for determination of Pd (II) metal. The reagent complexes with the metal to produce yellow colored complex which was then extracted in to butanol at pH 8.2 - 8.6 to form 1:2 ( metal-to-ligand ) complex, having absorption maxima at 415 nm. The molar absorptivity of the extracted species is 1.49 x 103 1 mol 1 cm 1 and sensitivity 0.071mg cm 2 The method permits separation and determination of palladium from palladium catalyst and binary mixture.

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A comparative Study on the Potential of Free Cells and Immobilized cells of Flavobacterium sp. in Treatment of Tannery Effluent

N. Elangovan, P.S. Sudhakar Gandhi and P.T. Kalaichelvan

A Flavobacterium sp. strain B2, isolated from paper mill effluent was tested for its ability to decolourize the tannery effluent. Apart from decolourization, parameters such as pH, dissolved solids, BOD, COD, total tannin, total phenol and total protein content of the treated effluent were also analysed. Reduction of 66.4 % was observed for total dissolved solids, 35.90 % and 86.85% for BOD and COD respectively was observed. Reduction of 34.98% for total tannin, 21.28 % for total phenol and 10.52% for total protein respectively was observed by treatment with free cells. With the results obtained for treatment of effluent with free growing cells of Flavobacterium sp., the work was extended with immobilized cells for effective treatment of the effluent.

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Reverse-Phase High Performance Liquid Chromatographic Method for the Analysis of JojobaOil

Subodh Kumar and K.K. Pant

An attempt to analyze the jojoba oil using HPLC on a UV-detector was made in the current study. The oil was analyzed using acetonitrile and methanol as mobile phase by RP-C18 column under optimal chromatographic conditions. A total number of eleven peaks could be identified during the analysis. The identified components were also confirmed by spectral (FTIR, PMR) techniques. Results show that jojoba oil contains ketonic, ester, alcoholic and vinyl functional groups.

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Effect of Biophysico-chemical Factors on Biosequestering of Chromium from the Tannery Effluent by Marine Cyanobacteria

Shailendra K. Sonawane, Richa Pawar, Anamika Patel, Sandhya Mishra, A. Tewari

Biosorption, where biological materials are used to sequester heavy metals, is considered to be one of the best alternatives for the treatment of metal rich wastewater with other physico-chemical methods. Extensive reports are available on the metal binding potential of microbial biosorbants. but very few reports are available on biophysico-chemical treatment for sequestering the heavy metals. This is a quite new method for treating effluents. Effluent from tannery industries contains high level of toxic chromium (20 - 40 mg/L). The permissible level of chromium is 2 mg/L for effluent discharge (The Environment Act. 1986). Chromium in high concentration is toxic to many species of plants, animals and marine flora and fauna. Initially exploratory experiments were carried out for selecting the best alternative of biological means for treating the effluent. Cyanobacterial consortium in the form of mat along with physicochemical treatment was observed to give the best results. (80-90 % reduction was observed in the effluent containing initial chromium level 12 mg/L of tannery effluent).

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Evaluation of Bioremediation Potential of Organophosphorus Pesticide Dimethoate 30% EC by Heavy Metal and Antibiotic Resistant Proteus Vulgaris Isolated from Ganges at Sreerampore,India

Manisha (Deb) Mandal, S. Mandal and N. K. Pal

The present work characterises an isolate of Proteus vulgaris from water sample of Ganges river at Sreerampore region near Kolkata. The isolate exhibited resistance to ampicillin, chloramphenicol, tetracycline, nalidixic acid and streptomycin (AR CR TR NxR SR) but sensitivity for ciprofloxacin, gentamycin and norfloxacin (CiR GR NR). The bacteria tolerated heavy metals: Hg2+, Cd2+ and Cu2+ up to the concentration of 0.25, 3 and 10 mM respectively. Pesticide resistance study demonstrated minimum inhibitory concentration (mg/ml) of four pesticides as dimethoate 30% EC [D(10)], methyl parathion 50% EC [M (50)], endosulfan 35% EC [E(100)] and carbaryl 50% EC [Cb(50)]. This strain when used as donor in conjugation experiment with a plasmidless Escherichia coli C 600 (NxR F-) recipient showed that the resistance for antibiotics, heavy metals and pesticides was not transferred. Resistance to C, T, Cd2+, Hg2+ and D was altered following plasmid curing with 0.1 mg/ml of ethidium bromide (EB). The P. vulgaris strain rendered resistivity towards D to the otherwise sensitive E. coli C600 strain in deoxycholate agar (DCA) plate containing D (5mg/ml). The cured strain of P. vulgaris did not show such characteristic. Following alkaline lysis method the wild type of P. vulgaris was found to harbour a single plasmid but the cured mutant one failed to show any plasmid. The result suggests that the plasmid of P. vulgaris encodes not only the resistance pattern of C T C2+ Hg2+ D but also is associated with the degradation of D.

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Review: Recent Trends in the Inorganic Analysis of Environmental Materials

V.Balaram

Several modern analytical methods have attained the capability of measuring most of the elements in the periodic table at sub-ng/g levels. Here an attempt has been made to give a brief account of the current state of analytical instrumentation available for the inorganic analysis of environmental materials. The relative merits and limitations of current instrumental techniques such as spectro-photometry, flame photometry, flame atomic absorption spectrometry (F-AAS), graphite furnace atomic absorption spectrometry (GF-AAS), ion chromatography (IC), X-ray fluorescence spectrometry (XRF), instrumental neutron activation analysis (INAA), inductively coupled plasmaatomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and high resolution inductively coupled plasma mass spectrometry (HR-ICPMS), and their potential applications in the field of analysis of environmental materials are reviewed. The detection limits of some of the important analytical techniques are compared. Rapid expansion in the application of metal speciation studies has provided a constant challenge for the analytical chemists. One of the most common approaches adopted by many laboratories has been the coupling of the separating powers of chromatographic techniques with the element-specific detection offered by atomic spectroscopic techniques like ICP-AES, ICP-MS and HR-ICP-MS. Use of environmental reference materials for calibrating the analytical instruments, and also as control samples for assessing the accuracy of the determination is one of the necessary tools for quality control. In addition, preparation of procedural blanks and adoption of effective sample preparation methods in a contamination-free environment also contribate to the quality of analytical data. These developments have been discussed, with examples. Specific advantages of ICP-MS and HR-ICP-MS techniques such as, extremely high sensitivity, limited interference effects, element coverage and speed would make them powerful tools in future for the analysis of a large variety of environmental materials.

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Use of Different Herbs as Coagulant and Coagulant aid for Water Purification

Parag Sadgir1, S. L. Gargh, A.N. Patel and Anamika Jain

A vast Indian population residing in rural areas is dependent on the supply of untreated water which is the root cause of their ailments. In cities a fairly large population is using water filters and aqua guards but the rural population is thriving on the contaminated water supply due to lack of financial resources and other pressing essentialities of life. In the process of developing a plant based substitute for economical safe approach for water purification against conventional chemical constituents plants were screened for evaluation of their efficiency for Turbidity removal and for antibacterial activity. Khas, Amla, Shingada. Hirda, Shevga, Elaichi and Anantvel are effective as coagulant and coagulant aid.

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Synthesis and Antimicrobial Studies of 3-alkoxy-5-(p-substituted aryl) Biguanidinopentan-2,4-diones and related Compounds

Lalit Kumar Baregama and G.L.Talesara

Reactive methylene b-diketo compound like acetyl acetone was converted to corresponding sodium salt and subsequently refluxed withw-bromoalkoxyphthalimides to give 3-alkoxyphthalimdopentan-2.4- dione 4a-c. Hydrolysis by Gabriels modified method gave 3-alkoxyaminopentan-2,4-dione salts 5a-c. Condensation of these salts with aryldicyandiamides yielded 3-alkoxy-(p-substituted aryl) biguanidinopentan-2,4-diones 6a-o. Synthesized compounds have been evaluated for their antibacterial and antifungal activities.

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Informative Article: Phytoconstituents and Worldwide uses of Ethnomedicinal Plants for Hypoglycemic Activity

Shipra Roy and Venu Agrawal

Plants are the only source of well established traditional and modern drugs and phytochemicals. Ethnobotanical surveys and documentation have been taken worldwide with a view of to prepare the inventories for food, fibre, medicine etc. During last few decades, several research papers have been published on various aspects of ethnobotany. It is thought to be quite fruitful to study the world wide ethnobotanical informations about medicinal plants having hypoglycemic activity. Some plants are common to many regions where some uses are unique to particular country. The present paper gives a worldwide account of 36 plants, which possess hypoglycemic activity.

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