Shweta Saraswat - Academia.edu (original) (raw)
Papers by Shweta Saraswat
Reviews In Environmental Science And Bio/technology, Aug 31, 2011
Metal accumulating plants exposed to toxic levels of zinc (Zn) and cadmium (Cd) uptake metals thr... more Metal accumulating plants exposed to toxic levels of zinc (Zn) and cadmium (Cd) uptake metals through extracellular and intracellular complexation with inorganic and organic ligand formation. However, little is known about the nature and formation mechanism of these metal-ligand complexes. Though, Zn and Cd have many similar chemical properties, yet their complexation and compartmentalization in plants vary with plant species. In principal, the question arises what factors govern Zn and Cd partitioning in plants? What form of the metal is taken up by the root, and is further distributed and accumulated in both vegetative and reproductive tissues? Therefore, the aim of present study is to address several questions concerning the mechanisms of Zn and Cd coordination and compartmentalization in plants using X-ray absorption spectroscopy (XAS) technique. XAS allows direct determination of elemental oxidation states and coordination environments in different plant tissues. This review article briefly explains some other important techniques of XAS; EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure), which are employed for determining Zn and Cd complexation within the plant. Therefore, In present review, the predominant as well as the minor chemical forms of Zn and Cd present in particular plant tissue have been discussed which could give better insight towards metal accumulation and detoxification mechanisms operated in plants. This information could assist in employing suitable hyperaccumulator plants for metal phytoextraction and reclamation of metal contaminated sites.
International Journal of Phytoremediation, Jun 6, 2018
The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla... more The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla verticillata, Phragmitis australis, Typha latifolia, and Spirodella polyrhiza from sewage-mixed industrial effluent. The fresh/dry weight and relative growth rate of each macrophyte decreased with increasing effluent concentration. H. verticillata and C. esculenta exhibited better growth at 50% effluent over control. The maximum Zn, Cd, and Pb accumulation (1008.23, 28.03, and 483.55 mg/kg dry wt., respectively) was recorded in C. esculenta, whereas Cr (114.48 mg/kg dry wt.) in H. verticillata at 100% effluent. Metal accumulation in roots of all plants species was higher (50%) initially with increasing effluent concentration and later transferred to shoots. All plants exhibited BCF >1.0 for all heavy metals, highest being for Zn (91.2) and Cd (75.2) in H. verticillata, for Cr (97.9) and Pb (103) in C. esculenta. Except S. polyrhhiza, all other plants exhibited TF <1.0. Maximum removal efficiency of Zn was 82.8% by H. verticillata, whilst that of Cr, Cd, and Pb by C. esculenta at 50% effluent, demonstrating wide applicability of H. verticillata and C. esculenta for treatment of mixed industrial effluent having heavy metals.
Chemistry and Ecology, Feb 1, 2009
... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretio... more ... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretion of root exudates of organic and inorganic nature, leading to changes in the soil&#x27;s biochemical and physical properties 2929. Walker, TS, Bais, HP, Grotewold, E. and Vivanco, M. 2003. ...
Advances in environmental engineering and green technologies book series, Apr 30, 2022
Soil pollution by heavy metals and metalloids has led to significant environmental and human heal... more Soil pollution by heavy metals and metalloids has led to significant environmental and human health hazards. Conventional remediation technologies for trace elements are cost-intensive and degrade soil quality. Phytoremediation offers an in-situ, ecological, and economic technology for remediation of metals from soil employing hyperaccumulators. However, selection of phytoremediation technology for a given site depends on soil conditions, contaminant nature and concentration, coverage and depth of polluted area, nature of plant used, etc. As phytoremediation is a slower process, it alone becomes inefficient and thus requires integration of various agronomic practices such as plant genotypes, soil properties, irrigation, fertilizers and chelators addition, crop rotation, planting methods, weed and pest control, and inoculation of plant growth promoting rhizobacteria and mycorrhizae to up-scaling phytoremediation technology for reclaiming and restoring contaminated sites effectively in a short time span.
Chemistry and Ecology, Dec 1, 2009
International Journal of Phytoremediation, Jan 15, 2011
The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed ... more The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced metal accumulation. Relatively greater amount of Zn than Cd was accumulated by L. leucocephala, which exceeded in roots with that of other parts. Remediation factor for Cd was maximum (3.6%) in S2 grown plant. Nodule numbers, their biomass, nitrogenase activity, and leghaemoglobin content were maximum in plants grown in S3 and minimum in S1 soil having maximum metals. Maximum soil organic C, total N, C(mic), and N(mic), respiration rate, ATP content, and enzymatic activities in response to phytoremediation was recorded in S3 followed by S2 and S1. Phytoremediation for a year enhanced extractable Zn and Cd by 36% and 45%, and their total removal by 20% and 30%, respectively from S2, which suggests the possible application of L. leucocephala for the remediation of metal contaminated sites and their fertility restoration by improving microbial functionalities and N-pool.
This survey reviews the growing use of patent data in economic analysis. After describing some of... more This survey reviews the growing use of patent data in economic analysis. After describing some of the main characteristics of patents and patent data, it focuses on the use of patents as an indicator of technological change. Cross-sectional and time-series studies of the relationship of patents to R&D expenditures are reviewed, as well as scattered estimates of the distribution of patent values and the value of patent rights, the latter being based on recent analyses of European patent renewal data. Time-series trends of patents granted in the U.S. are examined and their decline in the 1970s is found to be an artifact of the budget stringencies at the Patent Office. The longer run downward trend in patents per R&D dollar is interpreted not as an indication of diminishing returns but rather as a reflection of the changing meaning of such data over time. The conclusion is reached that, in spite of many difficulties and reservations, patent data remain a unique resource for the study of technical change.
Nano-biotechnology for Waste Water Treatment
Handbook of Research on Green Technologies for Sustainable Management of Agricultural Resources
Soil pollution by heavy metals and metalloids has led to significant environmental and human heal... more Soil pollution by heavy metals and metalloids has led to significant environmental and human health hazards. Conventional remediation technologies for trace elements are cost-intensive and degrade soil quality. Phytoremediation offers an in-situ, ecological, and economic technology for remediation of metals from soil employing hyperaccumulators. However, selection of phytoremediation technology for a given site depends on soil conditions, contaminant nature and concentration, coverage and depth of polluted area, nature of plant used, etc. As phytoremediation is a slower process, it alone becomes inefficient and thus requires integration of various agronomic practices such as plant genotypes, soil properties, irrigation, fertilizers and chelators addition, crop rotation, planting methods, weed and pest control, and inoculation of plant growth promoting rhizobacteria and mycorrhizae to up-scaling phytoremediation technology for reclaiming and restoring contaminated sites effectively i...
Journal of Scientific and …, 2007
A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain,... more A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain, where soil was irrigated by toxic metal rich brass and electroplating industrial effluent in suburban area of Moradabad, India. Spatial and seasonal variations of total heavy metal content in soil and their effect on physico-chemical and biological properties were studied in soil samples taken from 0-25, 25-50 and 50-75 cm soil depth. Except pH, all parameters were maximum in summer in surface soil at each site. Total metal content decreased with increasing distance from the effluent course. Physico-chemical values (pH, EC, C org , available N etc.) were found minimum at S1 and maximum at S3. Significant inhibition of microbial biomass C and N, respiration, dehydrogenase activity and microbial coefficient occurred in soils highly contaminated by heavy metals. There was a significant decrease in C mic /N mic ratio and an increase in metabolic quotient (qCO 2) with increasing metal concentration.
A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain,... more A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain, where soil was irrigated by toxic metal rich brass and electroplating industrial effluent in suburban area of Moradabad, India. Spatial and seasonal variations of total heavy metal content in soil and their effect on physico-chemical and biological properties were studied in soil samples taken from 0-25, 25-50 and 50-75 cm soil depth. Except pH, all parameters were maximum in summer in surface soil at each site. Total metal content decreased with increasing distance from the effluent course. Physico-chemical values (pH, EC, C org , available N etc.) were found minimum at S1 and maximum at S3. Significant inhibition of microbial biomass C and N, respiration, dehydrogenase activity and microbial coefficient occurred in soils highly contaminated by heavy metals. There was a significant decrease in C mic /N mic ratio and an increase in metabolic quotient (qCO 2) with increasing metal concentration.
World Journal of Microbiology and Biotechnology, 2022
Benzo[a]pyrene (BaP) is a high molecular weight polycyclic aromatic hydrocarbon produced as a res... more Benzo[a]pyrene (BaP) is a high molecular weight polycyclic aromatic hydrocarbon produced as a result of incomplete combustion of organic substances. Over the years, the release of BaP in the atmosphere has increased rapidly, risking human lives. BaP can form bonds with DNA leading to the formation of DNA adducts thereby causing cancer. Therefore addressing the problem of its removal from the environment is quite pertinent though it calls for a very cumbersome and tedious process owing to its recalcitrant nature. To resolve such issues many efforts have been made to develop physical and chemical technologies of BaP degradation which have neither been cost-effective nor eco-friendly. Microbial degradation of BaP, on the other hand, has gained much attention due to added advantage of the high level of microbial diversity enabling great potential to degrade the substance without impairing environmental sustainability. Microorganisms produce enzymes like oxygenases, hydrolases and cytochrome P450 that enable BaP degradation. However, microbial degradation of BaP is restricted due to several factors related to its bio-availability and soil properties. Technologies like bio-augmentation and bio-stimulation have served to enhance the degradation rate of BaP. Besides, advanced technologies such as omics and nano-technology have opened new doors for a better future of microbial degradation of BaP and related compounds.
International Journal of Phytoremediation, 2018
The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla... more The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla verticillata, Phragmitis australis, Typha latifolia, and Spirodella polyrhiza from sewage-mixed industrial effluent. The fresh/dry weight and relative growth rate of each macrophyte decreased with increasing effluent concentration. H. verticillata and C. esculenta exhibited better growth at 50% effluent over control. The maximum Zn, Cd, and Pb accumulation (1008.23, 28.03, and 483.55 mg/kg dry wt., respectively) was recorded in C. esculenta, whereas Cr (114.48 mg/kg dry wt.) in H. verticillata at 100% effluent. Metal accumulation in roots of all plants species was higher (50%) initially with increasing effluent concentration and later transferred to shoots. All plants exhibited BCF >1.0 for all heavy metals, highest being for Zn (91.2) and Cd (75.2) in H. verticillata, for Cr (97.9) and Pb (103) in C. esculenta. Except S. polyrhhiza, all other plants exhibited TF <1.0. Maximum removal efficiency of Zn was 82.8% by H. verticillata, whilst that of Cr, Cd, and Pb by C. esculenta at 50% effluent, demonstrating wide applicability of H. verticillata and C. esculenta for treatment of mixed industrial effluent having heavy metals.
International Journal of Phytoremediation, 2011
The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed ... more The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced metal accumulation. Relatively greater amount of Zn than Cd was accumulated by L. leucocephala, which exceeded in roots with that of other parts. Remediation factor for Cd was maximum (3.6%) in S2 grown plant. Nodule numbers, their biomass, nitrogenase activity, and leghaemoglobin content were maximum in plants grown in S3 and minimum in S1 soil having maximum metals. Maximum soil organic C, total N, C(mic), and N(mic), respiration rate, ATP content, and enzymatic activities in response to phytoremediation was recorded in S3 followed by S2 and S1. Phytoremediation for a year enhanced extractable Zn and Cd by 36% and 45%, and their total removal by 20% and 30%, respectively from S2, which suggests the possible application of L. leucocephala for the remediation of metal contaminated sites and their fertility restoration by improving microbial functionalities and N-pool.
Chemistry and Ecology, 2009
Praklische Uebtngen zutr Einfiuhrung in die Chemie. Von Dr. ALEXANDER SMITH, Professor fur Chemie... more Praklische Uebtngen zutr Einfiuhrung in die Chemie. Von Dr. ALEXANDER SMITH, Professor fur Chemie an der Unirersitit Chicago. Nach einer vom Verfasser besorgten Umarbeitung der zweiten amerikanischen Auflage ins Deutsche iibertragen von Professor Dr. F. HABER und Dr. M. STOECKER. Karlsruhe, Druck und Verlag der G. Braunschen Hofbuchdruckerei. Experiments Arranged for Students in General Chemistry.
Chemistry and Ecology, 2009
... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretio... more ... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretion of root exudates of organic and inorganic nature, leading to changes in the soil&#x27;s biochemical and physical properties 2929. Walker, TS, Bais, HP, Grotewold, E. and Vivanco, M. 2003. ...
Journal of Vector Borne Diseases
Biotech Today : An International Journal of Biological Sciences
Indian Journal of Medical Research, 2016
Background & objectives: The influence of temperature on the life cycle of mosquitoes as well as ... more Background & objectives: The influence of temperature on the life cycle of mosquitoes as well as on development of malaria parasite in mosquitoes is well studied. Most of the studies use outdoor temperature for understanding the transmission dynamics and providing projections of malaria. As the mosquitoes breed in water and rest usually indoors, it is logical to relate the transmission dynamics with temperature of micro-niche. The present study was, therefore, undertaken to understand the influence of different formats of temperature of different micro-niches on transmission of malaria for providing more realistic projections. Methods: The study was conducted in one village each of Assam and Uttarakhand States of India. Temperatures recorded from outdoor (air) as well as indoor habitats (resting place of mosquito) were averaged into daily, fortnightly and monthly and were used for determination of transmission windows (TWs) for Plasmodium vivax (Pv) and P. falciparum (Pf) based on minimum temperature threshold required for transmission. Results: The daily temperature was found more useful for calculation of sporogony than fortnightly and monthly temperatures. Monthly TWs were further refined using fortnightly temperature, keeping in view the completion of more than one life cycle of malaria vectors and sporogony of malaria parasite in a month. A linear regression equation was generated to find out the relationship between outdoor and indoor temperatures and R 2 to predict the percentage of variation in indoor temperature as a function of outdoor temperature at both localities. Interpretation & conclusions: The study revealed that the indoor temperature was more than outdoors in stable malarious area (Assam) but fluctuating in low endemic area like Uttarakhand. Transmission windows of malaria should be determined by transforming outdoor data to indoor and preferably at fortnightly interval. With daily recorded temperature, sporogonic and gonotrophic cycles can also be calculated which is otherwise not possible with monthly data. The study highlights that the projections made for malaria in view of climate change need to be seen with limitation of difference in outdoor and indoor temperatures at different locations, highlighting the need for local data generation at least at sub-district level.
Reviews In Environmental Science And Bio/technology, Aug 31, 2011
Metal accumulating plants exposed to toxic levels of zinc (Zn) and cadmium (Cd) uptake metals thr... more Metal accumulating plants exposed to toxic levels of zinc (Zn) and cadmium (Cd) uptake metals through extracellular and intracellular complexation with inorganic and organic ligand formation. However, little is known about the nature and formation mechanism of these metal-ligand complexes. Though, Zn and Cd have many similar chemical properties, yet their complexation and compartmentalization in plants vary with plant species. In principal, the question arises what factors govern Zn and Cd partitioning in plants? What form of the metal is taken up by the root, and is further distributed and accumulated in both vegetative and reproductive tissues? Therefore, the aim of present study is to address several questions concerning the mechanisms of Zn and Cd coordination and compartmentalization in plants using X-ray absorption spectroscopy (XAS) technique. XAS allows direct determination of elemental oxidation states and coordination environments in different plant tissues. This review article briefly explains some other important techniques of XAS; EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure), which are employed for determining Zn and Cd complexation within the plant. Therefore, In present review, the predominant as well as the minor chemical forms of Zn and Cd present in particular plant tissue have been discussed which could give better insight towards metal accumulation and detoxification mechanisms operated in plants. This information could assist in employing suitable hyperaccumulator plants for metal phytoextraction and reclamation of metal contaminated sites.
International Journal of Phytoremediation, Jun 6, 2018
The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla... more The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla verticillata, Phragmitis australis, Typha latifolia, and Spirodella polyrhiza from sewage-mixed industrial effluent. The fresh/dry weight and relative growth rate of each macrophyte decreased with increasing effluent concentration. H. verticillata and C. esculenta exhibited better growth at 50% effluent over control. The maximum Zn, Cd, and Pb accumulation (1008.23, 28.03, and 483.55 mg/kg dry wt., respectively) was recorded in C. esculenta, whereas Cr (114.48 mg/kg dry wt.) in H. verticillata at 100% effluent. Metal accumulation in roots of all plants species was higher (50%) initially with increasing effluent concentration and later transferred to shoots. All plants exhibited BCF >1.0 for all heavy metals, highest being for Zn (91.2) and Cd (75.2) in H. verticillata, for Cr (97.9) and Pb (103) in C. esculenta. Except S. polyrhhiza, all other plants exhibited TF <1.0. Maximum removal efficiency of Zn was 82.8% by H. verticillata, whilst that of Cr, Cd, and Pb by C. esculenta at 50% effluent, demonstrating wide applicability of H. verticillata and C. esculenta for treatment of mixed industrial effluent having heavy metals.
Chemistry and Ecology, Feb 1, 2009
... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretio... more ... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretion of root exudates of organic and inorganic nature, leading to changes in the soil&#x27;s biochemical and physical properties 2929. Walker, TS, Bais, HP, Grotewold, E. and Vivanco, M. 2003. ...
Advances in environmental engineering and green technologies book series, Apr 30, 2022
Soil pollution by heavy metals and metalloids has led to significant environmental and human heal... more Soil pollution by heavy metals and metalloids has led to significant environmental and human health hazards. Conventional remediation technologies for trace elements are cost-intensive and degrade soil quality. Phytoremediation offers an in-situ, ecological, and economic technology for remediation of metals from soil employing hyperaccumulators. However, selection of phytoremediation technology for a given site depends on soil conditions, contaminant nature and concentration, coverage and depth of polluted area, nature of plant used, etc. As phytoremediation is a slower process, it alone becomes inefficient and thus requires integration of various agronomic practices such as plant genotypes, soil properties, irrigation, fertilizers and chelators addition, crop rotation, planting methods, weed and pest control, and inoculation of plant growth promoting rhizobacteria and mycorrhizae to up-scaling phytoremediation technology for reclaiming and restoring contaminated sites effectively in a short time span.
Chemistry and Ecology, Dec 1, 2009
International Journal of Phytoremediation, Jan 15, 2011
The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed ... more The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced metal accumulation. Relatively greater amount of Zn than Cd was accumulated by L. leucocephala, which exceeded in roots with that of other parts. Remediation factor for Cd was maximum (3.6%) in S2 grown plant. Nodule numbers, their biomass, nitrogenase activity, and leghaemoglobin content were maximum in plants grown in S3 and minimum in S1 soil having maximum metals. Maximum soil organic C, total N, C(mic), and N(mic), respiration rate, ATP content, and enzymatic activities in response to phytoremediation was recorded in S3 followed by S2 and S1. Phytoremediation for a year enhanced extractable Zn and Cd by 36% and 45%, and their total removal by 20% and 30%, respectively from S2, which suggests the possible application of L. leucocephala for the remediation of metal contaminated sites and their fertility restoration by improving microbial functionalities and N-pool.
This survey reviews the growing use of patent data in economic analysis. After describing some of... more This survey reviews the growing use of patent data in economic analysis. After describing some of the main characteristics of patents and patent data, it focuses on the use of patents as an indicator of technological change. Cross-sectional and time-series studies of the relationship of patents to R&D expenditures are reviewed, as well as scattered estimates of the distribution of patent values and the value of patent rights, the latter being based on recent analyses of European patent renewal data. Time-series trends of patents granted in the U.S. are examined and their decline in the 1970s is found to be an artifact of the budget stringencies at the Patent Office. The longer run downward trend in patents per R&D dollar is interpreted not as an indication of diminishing returns but rather as a reflection of the changing meaning of such data over time. The conclusion is reached that, in spite of many difficulties and reservations, patent data remain a unique resource for the study of technical change.
Nano-biotechnology for Waste Water Treatment
Handbook of Research on Green Technologies for Sustainable Management of Agricultural Resources
Soil pollution by heavy metals and metalloids has led to significant environmental and human heal... more Soil pollution by heavy metals and metalloids has led to significant environmental and human health hazards. Conventional remediation technologies for trace elements are cost-intensive and degrade soil quality. Phytoremediation offers an in-situ, ecological, and economic technology for remediation of metals from soil employing hyperaccumulators. However, selection of phytoremediation technology for a given site depends on soil conditions, contaminant nature and concentration, coverage and depth of polluted area, nature of plant used, etc. As phytoremediation is a slower process, it alone becomes inefficient and thus requires integration of various agronomic practices such as plant genotypes, soil properties, irrigation, fertilizers and chelators addition, crop rotation, planting methods, weed and pest control, and inoculation of plant growth promoting rhizobacteria and mycorrhizae to up-scaling phytoremediation technology for reclaiming and restoring contaminated sites effectively i...
Journal of Scientific and …, 2007
A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain,... more A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain, where soil was irrigated by toxic metal rich brass and electroplating industrial effluent in suburban area of Moradabad, India. Spatial and seasonal variations of total heavy metal content in soil and their effect on physico-chemical and biological properties were studied in soil samples taken from 0-25, 25-50 and 50-75 cm soil depth. Except pH, all parameters were maximum in summer in surface soil at each site. Total metal content decreased with increasing distance from the effluent course. Physico-chemical values (pH, EC, C org , available N etc.) were found minimum at S1 and maximum at S3. Significant inhibition of microbial biomass C and N, respiration, dehydrogenase activity and microbial coefficient occurred in soils highly contaminated by heavy metals. There was a significant decrease in C mic /N mic ratio and an increase in metabolic quotient (qCO 2) with increasing metal concentration.
A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain,... more A field study was conducted at three sites (S1-S3) of 500m longitudinal transect along the drain, where soil was irrigated by toxic metal rich brass and electroplating industrial effluent in suburban area of Moradabad, India. Spatial and seasonal variations of total heavy metal content in soil and their effect on physico-chemical and biological properties were studied in soil samples taken from 0-25, 25-50 and 50-75 cm soil depth. Except pH, all parameters were maximum in summer in surface soil at each site. Total metal content decreased with increasing distance from the effluent course. Physico-chemical values (pH, EC, C org , available N etc.) were found minimum at S1 and maximum at S3. Significant inhibition of microbial biomass C and N, respiration, dehydrogenase activity and microbial coefficient occurred in soils highly contaminated by heavy metals. There was a significant decrease in C mic /N mic ratio and an increase in metabolic quotient (qCO 2) with increasing metal concentration.
World Journal of Microbiology and Biotechnology, 2022
Benzo[a]pyrene (BaP) is a high molecular weight polycyclic aromatic hydrocarbon produced as a res... more Benzo[a]pyrene (BaP) is a high molecular weight polycyclic aromatic hydrocarbon produced as a result of incomplete combustion of organic substances. Over the years, the release of BaP in the atmosphere has increased rapidly, risking human lives. BaP can form bonds with DNA leading to the formation of DNA adducts thereby causing cancer. Therefore addressing the problem of its removal from the environment is quite pertinent though it calls for a very cumbersome and tedious process owing to its recalcitrant nature. To resolve such issues many efforts have been made to develop physical and chemical technologies of BaP degradation which have neither been cost-effective nor eco-friendly. Microbial degradation of BaP, on the other hand, has gained much attention due to added advantage of the high level of microbial diversity enabling great potential to degrade the substance without impairing environmental sustainability. Microorganisms produce enzymes like oxygenases, hydrolases and cytochrome P450 that enable BaP degradation. However, microbial degradation of BaP is restricted due to several factors related to its bio-availability and soil properties. Technologies like bio-augmentation and bio-stimulation have served to enhance the degradation rate of BaP. Besides, advanced technologies such as omics and nano-technology have opened new doors for a better future of microbial degradation of BaP and related compounds.
International Journal of Phytoremediation, 2018
The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla... more The present study assessed Zn, Cr, Cd, and Pb removal efficiency of Colocasia esculenta, Hydrilla verticillata, Phragmitis australis, Typha latifolia, and Spirodella polyrhiza from sewage-mixed industrial effluent. The fresh/dry weight and relative growth rate of each macrophyte decreased with increasing effluent concentration. H. verticillata and C. esculenta exhibited better growth at 50% effluent over control. The maximum Zn, Cd, and Pb accumulation (1008.23, 28.03, and 483.55 mg/kg dry wt., respectively) was recorded in C. esculenta, whereas Cr (114.48 mg/kg dry wt.) in H. verticillata at 100% effluent. Metal accumulation in roots of all plants species was higher (50%) initially with increasing effluent concentration and later transferred to shoots. All plants exhibited BCF >1.0 for all heavy metals, highest being for Zn (91.2) and Cd (75.2) in H. verticillata, for Cr (97.9) and Pb (103) in C. esculenta. Except S. polyrhhiza, all other plants exhibited TF <1.0. Maximum removal efficiency of Zn was 82.8% by H. verticillata, whilst that of Cr, Cd, and Pb by C. esculenta at 50% effluent, demonstrating wide applicability of H. verticillata and C. esculenta for treatment of mixed industrial effluent having heavy metals.
International Journal of Phytoremediation, 2011
The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed ... more The study deals with phytoextraction of Zn and Cd by Leucaena leucocephala grown on effluent fed and low nitrogen soils collected from S1, S2, and S3 sites, representing decreasing metal content with increasing distance from the effluent drain. Plant nitrogen fixation potential and soil micro-biochemical attributes against metal stress were also assessed. Increasing soil metal content and plant growth enhanced metal accumulation. Relatively greater amount of Zn than Cd was accumulated by L. leucocephala, which exceeded in roots with that of other parts. Remediation factor for Cd was maximum (3.6%) in S2 grown plant. Nodule numbers, their biomass, nitrogenase activity, and leghaemoglobin content were maximum in plants grown in S3 and minimum in S1 soil having maximum metals. Maximum soil organic C, total N, C(mic), and N(mic), respiration rate, ATP content, and enzymatic activities in response to phytoremediation was recorded in S3 followed by S2 and S1. Phytoremediation for a year enhanced extractable Zn and Cd by 36% and 45%, and their total removal by 20% and 30%, respectively from S2, which suggests the possible application of L. leucocephala for the remediation of metal contaminated sites and their fertility restoration by improving microbial functionalities and N-pool.
Chemistry and Ecology, 2009
Praklische Uebtngen zutr Einfiuhrung in die Chemie. Von Dr. ALEXANDER SMITH, Professor fur Chemie... more Praklische Uebtngen zutr Einfiuhrung in die Chemie. Von Dr. ALEXANDER SMITH, Professor fur Chemie an der Unirersitit Chicago. Nach einer vom Verfasser besorgten Umarbeitung der zweiten amerikanischen Auflage ins Deutsche iibertragen von Professor Dr. F. HABER und Dr. M. STOECKER. Karlsruhe, Druck und Verlag der G. Braunschen Hofbuchdruckerei. Experiments Arranged for Students in General Chemistry.
Chemistry and Ecology, 2009
... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretio... more ... Shweta Saraswat a &amp; JPN Rai a * pages 1-11. ... This might be due to the excretion of root exudates of organic and inorganic nature, leading to changes in the soil&#x27;s biochemical and physical properties 2929. Walker, TS, Bais, HP, Grotewold, E. and Vivanco, M. 2003. ...
Journal of Vector Borne Diseases
Biotech Today : An International Journal of Biological Sciences
Indian Journal of Medical Research, 2016
Background & objectives: The influence of temperature on the life cycle of mosquitoes as well as ... more Background & objectives: The influence of temperature on the life cycle of mosquitoes as well as on development of malaria parasite in mosquitoes is well studied. Most of the studies use outdoor temperature for understanding the transmission dynamics and providing projections of malaria. As the mosquitoes breed in water and rest usually indoors, it is logical to relate the transmission dynamics with temperature of micro-niche. The present study was, therefore, undertaken to understand the influence of different formats of temperature of different micro-niches on transmission of malaria for providing more realistic projections. Methods: The study was conducted in one village each of Assam and Uttarakhand States of India. Temperatures recorded from outdoor (air) as well as indoor habitats (resting place of mosquito) were averaged into daily, fortnightly and monthly and were used for determination of transmission windows (TWs) for Plasmodium vivax (Pv) and P. falciparum (Pf) based on minimum temperature threshold required for transmission. Results: The daily temperature was found more useful for calculation of sporogony than fortnightly and monthly temperatures. Monthly TWs were further refined using fortnightly temperature, keeping in view the completion of more than one life cycle of malaria vectors and sporogony of malaria parasite in a month. A linear regression equation was generated to find out the relationship between outdoor and indoor temperatures and R 2 to predict the percentage of variation in indoor temperature as a function of outdoor temperature at both localities. Interpretation & conclusions: The study revealed that the indoor temperature was more than outdoors in stable malarious area (Assam) but fluctuating in low endemic area like Uttarakhand. Transmission windows of malaria should be determined by transforming outdoor data to indoor and preferably at fortnightly interval. With daily recorded temperature, sporogonic and gonotrophic cycles can also be calculated which is otherwise not possible with monthly data. The study highlights that the projections made for malaria in view of climate change need to be seen with limitation of difference in outdoor and indoor temperatures at different locations, highlighting the need for local data generation at least at sub-district level.