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Biosorption of Malathion from Aqueous Solutions Using Herbal Leaves Powder

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American Journal of Analytical Chemistry 2011年第8期2卷 37-45页

作者： Tharakeswar Yadamari Kalyan Yakkala Gangadhar Battala ramakrishna naidu gurijala 不详

Commonly available herbal leaves powder namely Achyranthes aspera (uthareni) and Phyllanthus niruri (Nela usiri) are used as biosorbents for the removal of malathion in the present investigation. The efficiency of the biosorbents is tested for the determination of malathion using batch experiments under controlled conditions as a function of pH, contact time, initial malation concentration and the optimization amount of biosorbents. The quantification of malathion in aqueous samples, before and after equilibration with biosorbents is carried out by existing spectrophotometric method based on the oxidation of malathion with excess N-bromosuccinimide (NBS) and Rhodamine B at (?max = 550 nm) is used for the unconsumed NBS. The biosorption capacities are found to be pH dependent. The maximum adsorption is noticed at pH = 6 with a contact time of 120 minutes. Biosorption equilibrium isotherms are plotted for malathion uptake capacity (Qe) against residual malathion concentration (Ce) in solution. The Qe versus Ce sorption isotherms relationship is expressed mathematically by Langmuir and Freundlich models. The removal of malathion using biosorbents Achyranthes aspera (Uthareni) and Phyllanthus niruri (Nela usiri) from spiked river water samples are found to be 94% and 96% respectively. The developed eco-friendly potential biosorbents indicate that the present method can be successfully applied for the quantitative determination and removal of malathion from real water samples.

关键词： Biosorption Malathion Achyranthes aspera (Uthareni) and Phyllanthus niruri (Nela usiri) Isotherm Models

Biosorption of Cd (II), Cr (VI) &Pb (II) from Aqueous Solution Using <i>Mirabilis jalapa</i>as Adsorbent

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Journal of Encapsulation and Adsorption Sciences 2015年第2期5卷 93-104页

作者： Shaik Abdul Shahanaz Begum Yadamari Tharakeswar Yakkala Kalyan gurijala ramakrishna naidu Department of Environmental Sciences Sri Venkateswara University Tirupati India

Mirabilis jalapa (chandrakantha) leaves were used as a biosorbent for the removal of toxic metals ions cadmium (II), chromium (VI) and lead (II) from water. The physiochemical properties of the developed biosorbent were studied using FTIR. The efficiency of this developed biosorbent was tested using batch experiments under controlled conditions such as a function of pH, contact time, initial metal concentration and the optimization amount of biosorbent. The residual metallic ion concentrations of cadmium (II), chromium (VI) and lead (II) were determined using AAS. The biosorption capacity of Mirabilis jalapa was found to be pH dependant and the percentage removal of cadmium (II), chromium (VI) and lead (II) was increased with increasing adsorbate solution pH and a maximum value was reached at an equilibrium pH = 6 for cadmium (II), pH = 5.5 for chromium (VI) and pH 4.5 for lead (II) respectively. The equilibrium time required for the saturation loading of cadmium (II), chromium (VI) and lead (II) in the biosorbent was found to be about 120 min. The obtained equilibrium biosorption data was fitted to the linear forms of Freundlich isotherms. The results proved the efficiency of Mirabilis jalapa leaves powder as biosorbent for the removal of metal ions and it can be used for the development of an efficient, clean and novel technology for waste water treatment.

关键词： Mirabilis jalapa Biosorption Toxic Metal Ions Isotherm Models

Optical Chemical Sensor for Screening Cadmium (II) in Natural Waters

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Journal of Sensor Technology 2012年第2期2卷 68-74页

作者： Yadamari Tharakeswar Yakkala Kalyan Battala Gangadhar Korivi Sujan Kumar gurijala ramakrishna naidu Department of Environmental Sciences Sri Venkateswara University Tirupati India

Membrane based optical chemical sensor (optode) for Cd(II) was developed by the immobilization of a dye 1-(2-Pyridylazo)-2-Napthol (PAN) in the Tri-(2-Ethylhexyl) Phosphate (TEHP) plasticized Cellulose Triacetate (CTA) matrix. Various combinations of PAN immobilized in the cellulose triacetate CTA and Polystyrene (PS) matrices plasticized with Tri-(2-Ethylhexyl) Phosphate TEHP, 2-Nitrophenyl Octyl Ether (NPOE) and Dioctyl Phthalate (DOP) were studied to arrive a suitable composition and found that the optode does not require any extractant to produce a distinct colour change on complexation with Cd(II). On sorption of Cd(II) in the optode matrix, PAN changes color of the optode from golden yellow to violet red having a maximum absorbance (lmax = 553 nm) within 150 min of total equilibration time at pH = 7.5. The optode developed in the present work was studied for its analytical application for Cd(II) in the aqueous samples by spectrophotometry and as well as Flame Atomic Absorption Spectrophotometry (FAAS). This preconcentrated optode showed a linear response by UV-visible spectrophotometry at λmax = 553 nm over a concentration range of 10 ng/mL–1 to 500 ng/mL–1 of Cd(II) ions. Where as the aqueous solutions was also subjected to FAAS before and after equilibration of the optode and found to be linear in the concentration range of 250 ng/mL–1 to 5000 ng/mL–1 of Cd(II) ions. The optode found to be reversible and can be desorbed by equilibrating it with 0.01 mol/L–1 HNO3. The applicability of the developed optode in real samples was studied by determining cadmium in the natural waters spiked with a known amount of Cd(II) ions.

关键词： Optode Cd(II) Ions 1-(2-Pyridylazo)-2-Napthol (PAN) FAAS

Imprinted Polymer Inclusion Membrane Based Potentiometric Sensor for Determination and Quantification of Diethyl Chlorophosphate in Natural Waters

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American Journal of Analytical Chemistry 2011年第3期2卷 376-382页

作者： Varada Vishnuvardhan Yakkala Kalyan Krishnapillai Padmajakumari Prathish Battala Gangadhar Yadamari Tharakeswar Talasila Prasada Rao gurijala ramakrishna naidu Department of Environmental Sciences S.V. University Tirupati – 517 502 India

Biomimetic potentiometric sensor for the determination of diethyl chlorophosphate was developed using im- printed polymer inclusion membrane strategy. Semi-covalent imprinted and non-imprinted polymer particles were synthesized and found that non-imprinted polymer inclusion membrane was unstable in contrast to im- printed polymer inclusion membrane in determination and quantification of diethyl chlorophosphate. Im- printed polymer inclusion membrane based sensor found to be pH dependant with a 5 min equilibrium response time at pH = 10.5 and linearly responds to diethyl chlorophosphate in the concentration range of 1 × 10–9 to 1 × 10–4 and 1 × 10–4 to 1 × 10–1 mol●L–9 with a detection limit of 1 × 10–9 mol●L–1 (0.17 ppb). It was found that diethyl chlorophosphate response was selective against various selected interferents like pinacolyl methylphosphonate, dimethyl methyl phosphonate, methylphosphonic acid, Phorate and 2, 4-D. The devel- oped sensor was found to be stable for 3 months and can be reusable more than 30 times without loosing sensitivity. The developed sensor was successfully applied for the determination of diethyl chlorophosphate in natural waters.

关键词： Sensor Imprinted Polymer Inclusion Membrane Potentiometry Diethyl Chlorophosphate Natural Waters

Antioxidant and hepatoprotective effects of Boswellia ovalifoliolata bark extracts

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Chinese Journal of Natural Medicines 2014年第9期12卷 663-671页

作者： Bandari Uma Mahesh Shweta Shrivastava Rajeswara Rao Pragada V.G.M.naidu ramakrishna Sistla Department of Pharmacology A.U.College of Pharmaceutical Sciences Andhra University Vishakhapatnam Andhra Pradesh India -530003 Department of Pharmacology & Toxicology National Institute of Pharmaceutical Education & Research (NIPER-Hyderabad) Balanagar Hyderabad Andhra Pradesh India-500037 Pharmacology Division Indian Institute of Chemical Technology Habsiguda Hyderabad Andhra Pradesh ndia-500007

Paracetamol(PCM) hepatotoxicity is related to reactive oxygen species(ROS) formation and excessive oxidative stress; natural antioxidant compounds have been tested as an alternative therapy. This study evaluated the hepatoprotective activity of an alcoholic extract of Boswellia ovalifoliolata(BO) bark against PCM-induced hepatotoxicity. BO extract also demonstrated antioxidant activity in vitro, as well as scavenger activity against 2, 2-diphenyl-1-picrylhydrazyl. Administration of PCM caused a significant increase in the release of transaminases, alkaline phosphatase, and lactate dehydrogenase in serum. Significant enhancement in hepatic lipid peroxidation and marked depletion in reduced glutathione were observed after parac intoxication with severe alterations in liver histology. BO treatment was able to mitigate hepatic damage induced by acute intoxication of PCM and showed a pronounced protective effect against lipid peroxidation, deviated serum enzymatic variables, and maintained glutathione status toward control. The results clearly demonstrate the hepatoprotective effect of BO against the toxicity induced by PCM.

关键词： extracts peroxidation glutathione dehydrogenase protective alcoholic antioxidant ABTS histology curcumin

Anti-Amnesic Activity of Vitex Negundo in Scopolamine Induced Amnesia in Rats

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Pharmacology & Pharmacy 2010年第1期1卷 1-8页

作者： Abhinav Kanwal Jogender Mehla Madhusudana Kuncha Vegi Ganga Modi naidu Yogendra Kumar Gupta ramakrishna Sistla Division of Pharmacology Indian Institute of Chemical Technology (IICT) National Institute of Pharmaceutical Education and Research (NIPER) Department of Pharmacology All India Institute of Medical Sciences (AIIMS)

In the present study we investigated the anti-amnesic activity of Vitex negundo in scopolamine induced amnesia in rats. Wistar rats (180-200 g) were trained on active avoidance task. Each animal received session of 15 trials with inter trial duration of 15 s for 5 days. Scopolamine (3 mg/kg, i.p) was administered at different time periods on the basis of stages of memory i.e acquisition, consolidation and retention in different groups (n = 6). Effect of Vitex negundo extract was evaluated and compared to a standard drug, Donepezil. Significant (p <0.05) increase in the avoidance response on the 5th session has been observed as compared to 1st session in control group. Scopolamine treatment significantly (p <0.05) reduced the avoidance response compared to control. Extract treated groups shown significant (p <0.05) increase in number of avoidance responses as compared to scopolamine treated groups. Increased oxidative stress in brain after scopolamine treatment, as observed by increase in MDA &decrease in GSH &SOD, was lowered in the groups treated with extracts. AChE activity was also improved after V. negundo treatment. Results of the study have shown that V. negundo treated groups decrease the phenomenon of amnesia by increasing learning of memory through antioxidant effect and decreasing AChE activity.

关键词： Vitex Negundo Amnesia Acetylcholinestrase Scopolamine Learning and Memory Oxidative Stress

Himalayan Warming and Climate Change in India

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American Journal of Climate Change 2016年第4期5卷 558-574页

作者： Vadlamudi Brahmananda Rao Sergio Henrique Franchito Renato Orrú Pedroso Gerólamo Emanuel Giarolla Surireddi Satyavenkata Venkata Siva ramakrishna Bodda Ravi Srinivasa Rao Chennu Vankateswara naidu Center for Weather Prediction and Climate Studies INPE S?o José dos Campos S.P. Brazil Department of Meteorology and Oceanography Andhra University Visakhapatanam India

Recent studies showed that the Himalayan glaciers are reducing alarmingly. This is attributed to global warming. Since the melt water of Himalayan glaciers and snow is the principal source of water for several rivers, a decrease of this source is a calamity for the large fraction of global population living in nearby regions such as India. In Asia for the 60% global population only 36% of global water is available. Any further decrease of this vital necessity makes the very existence of billions of people doubtful. Here we show, using both observations and one IPCC-AR4 model with high horizontal resolution, that the Himalayan region in fact underwent a maximum warming of 2.5°C from 1950 to 1999 and would reach the highest temperature rise of 9°C in 2100. Temperature and rainfall variations determine a simple climate classification proposed by Köppen. We show changes that occur in climate and biosphere using this classification. Also we discussed the impact of warming and resulting changes in Köppen climates on the floods and malaria in India.

关键词： Himalayan Glaciers Global Warming Floods in India Malaria in India IPCC AR4 Model Köppen Climates