Papers by Tejo Prakash Nagaraja
Journal of Nutritional Science and Vitaminology, 2013
In an effort to produce selenium (Se)-fortifying edible mushrooms, five species of oyster mushroo... more In an effort to produce selenium (Se)-fortifying edible mushrooms, five species of oyster mushroom (Pleurotus sp.), were cultivated on Se-rich wheat straw collected from a seleniferous belt of Punjab, India. Total selenium was analyzed in the selenium hyperaccumulated wheat straw and the fruiting bodies. Significantly high levels (p,0.0001) of Se uptake were observed in fruiting bodies of all mushrooms grown on Se-rich wheat straw. To the best of our knowledge, accumulation and quantification of selenium in mushrooms has hitherto not been reported with substrates naturally enriched with selenium. The results demonstrate the potential of selenium-rich agricultural residues as substrates for production of Se-enriched mushrooms and the ability of different species of oyster mushrooms to absorb and fortify selenium. The study envisages potential use of selenium-rich agricultural residues towards cultivation of Se-enriched mushrooms for application in selenium supplementation or neutraceutical preparations.
Epoxidized methyl esters (EMO) with their high oxirane ring reactivity, acts as a raw material in... more Epoxidized methyl esters (EMO) with their high oxirane ring reactivity, acts as a raw material in the synthesis of various industrial chemicals including polymers, stabilizers, plasticizers, glycols, polyols, carbonyl compounds, biolubricants etc. EMO has been generally quantified by the gas chromatography (GC) and high performance liquid chromatography (HPLC) techniques. Taking into the account of the limitations of these techniques, two qHNMR based equations have been proposed for the quantification of EMO in the mixture of EMO and methyl esters (MO). The validity of the proposed method was determined using standard mixtures of MO and EMO having different molar concentrations. The developed equations have been applied on the samples of EMO prepared from oleic acid in two step process viz., esterification followed by epoxidation. The qHNMR based EMO quantification showed acceptable agreement with the results obtained from HPLC analysis.
Biological trace element research, Jan 16, 2017
The primary objective of this study is to assess the influence of water extracts of Plantago majo... more The primary objective of this study is to assess the influence of water extracts of Plantago major L., Plantago lanceolata L., and Plantago maxima Juss. ex Jacq. leaves on tissue trace element content in healthy adult Wistar rats. Twenty-eight female Wistar rats consumed pure drinking water or one of the three aqueous extracts of Plantago for 1 month. The extracts and liver, serum, hair, and adipose tissue of the rats were examined for trace element contents using inductively coupled plasma mass spectrometry. The aqueous extracts of Plantago species contained significant levels of trace elements, which were highest in P. lanceolata and P. major. The administration of every extract led to an increase in V and Si levels in the rats. At the same time, the consumption of P. lanceolata aqueous extract resulted in the accumulation of toxic elements (As, Pb) in the rats' tissues. Despite the rather high concentration of heavy metals in the P. major leaf extract, its administration did ...
Defence science journal
A fungal strain, Syncephalastrum racemosum, was isolated from oil-leak contaminated soils from Ka... more A fungal strain, Syncephalastrum racemosum, was isolated from oil-leak contaminated soils from Kanpur, India. The strain was examined for potential to emulsify soybean oil using a 18 per cent oil supplement as carbon source in minimal salt medium. On 72 h growth of the fungus in oil and salt medium, the cellfree supernatant (CFS) showed presence of mono-and di-glycerides indicating degradation of oils to free fatty acids (FFAs). Increasing concentration of oil resulted in enhanced formation of FFAs. The degradation process was observed to be related to the emulsification activity in CFS which was observed to increase with time. The study reports the emulsification and hydrolytic activity of S. racemosum, an activity that can be exploited for increasing the accessibility and treatment of hazardous substance including hydrophobic explosives.
Journal of Biologically Active Products from Nature, 2014
Taylor & Francis makes every effort to ensure the accuracy of all the information (the "Content")... more Taylor & Francis makes every effort to ensure the accuracy of all the information (the "Content") contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content.
Journal of Oleo Science, 2013
Fungus isolate, Aspergillus sp. (RBD01), which was isolated from biocontaminated clarified butter... more Fungus isolate, Aspergillus sp. (RBD01), which was isolated from biocontaminated clarified butter was evaluated for its potential to transesterify used edible and non-edible oils for generation of alkyl esters, when used as biocatalyst as dry biomass. The work aimed at determining the potential of dry biomass of Aspergillus sp. (RBD01) to transesterify used cottonseed oil and non-edible oils viz., jatropha and karanj under various culture conditions. A conversion of oil (cotton seed) to ethyl ester to the extent of 84% was obtained at reaction temperature of 35℃, with 20% biomass and step-wise addition of ethanol at 1:5 molar ratio (oil to ethanol), within total reaction time of 36 h. Under similar conditions, transesterification of Jatropha and Karanj oils resulted in only 75 and 78.2% ethyl ester. Further, with reference to the effect of frying on transesterification, increase in frying time decreased the extent of transesterification from 84% to 30%.
Journal of Agricultural Science, 2010
Microorganisms are major key players for sustaining the soil quality degraded by intensive use of... more Microorganisms are major key players for sustaining the soil quality degraded by intensive use of synthetic chemicals for increasing crop production and therefore, use of them as inoculants or biofertilizers is an integral part of sustainable agriculture. An effort was, therefore, made to examine the effect of cellulose degrading bacterial isolates on legume (Chickpea) based cropping systems. No chemical/organic fertilizer was added during this study. The bacterial isolates viz., Serratia sp. (MSK1 and MSK24) and Pseudomonas sp. (MSK13) exhibiting cellulase activity of 3.83, 4.21 and 4.52 mM glucose ml -1 h -1 respectively were introduced as inoculants. The ERIC-PCR results showed the good survivability of introduced strains in soil, measured after crop harvest, respectively 40.2. 56.8 and 34.4 %. A significant enhancement in organic carbon and available phosphorus was observed in the inoculated plots over the control plot, indicating beneficial effect of the bioaugmentation of these inoculants.
Current Chemical Biology, 2013
The discovery of selenocysteine as the 21 st amino acid has revolutionized the understanding of t... more The discovery of selenocysteine as the 21 st amino acid has revolutionized the understanding of the significance of the essential micronutrient selenium in human and animal health. About 25 different selenoproteins have been identified that collectively function to detoxify reactive oxygen and nitrogen species (RONS) and thus aid in maintaining an optimal redox tone as a vital component of the antioxidant defense system of cells. Knowledge about the physiological properties of the redox-sensitive transcription factors like nuclear factor-kappa B (NF-κB) has made it clear that oxidative stress is an important factor that triggers and sustains inflammation in various disease states. Moreover, there is emerging epidemiological data suggesting a positive association between selenium deficiency and the prevalence of diseases such as atherosclerosis, rheumatoid arthritis, viral infections including HIV-AIDS, and cancer, where chronic inflammation forms the underlying basis of the disease. Recent studies in our laboratory have shown that selenoproteins modulate many cellular regulatory pathways that influence the expression of pro-and anti-inflammatory genes. Thus, elucidation of the diverse molecular mechanisms involved in the anti-inflammatory properties of selenium is important to appreciate its role in disease prevention and treatment. This article reviews the current status of knowledge on the biology of selenium with an emphasis on inflammation.
Metallomics, 2012
Several novel selenium containing compounds were characterized in staple crops (wheat, rice and m... more Several novel selenium containing compounds were characterized in staple crops (wheat, rice and maize) grown on soils naturally rich in selenium. A dedicated method based on the coupling of liquid chromatography with multiplexed detection (ICP-MS, ESI-Orbitrap MS(/MS)) was developed for the speciation of low-molecular weight (<5 kDa) selenium metabolites. Nine species present in different proportions as a function of the crop type were identified by cation-exchange HPLC-ESI-Orbitrap MS on the basis of the accurate molecular mass and MS/MS spectra. The natural origin of these species was then validated by varying extraction conditions and by using hydrophilic interaction LC (HILIC)-ESI-Orbitrap MS(/MS). Among the identified compounds, Se-containing monosaccharides (hexose moiety, m/z 317 and m/z 358) or Se-containing disaccharides (hexose-pentose moiety, m/z 407 and m/z 408) were the first selenosugars reported in edible plants. It is also the first report of the presence of 2,3-dihydroxypropionyl-selenolanthionine (m/z 345) in rice. Because these crops can be an important source of selenium in animal and human nutrition, the understanding of the origin and the fate of these species during metabolic processes will be of great interest.
Food Chemistry, 2013
Cultivation of saprophytic fungi on selenium-rich substrates can be an effective means to produce... more Cultivation of saprophytic fungi on selenium-rich substrates can be an effective means to produce selenium-fortified food. Pleurotus florida, an edible species of oyster mushrooms, was grown on wheat straw from the seleniferous belt of Punjab (India) and its potential to mobilize and accumulate selenium from the growth substrate was studied. Selenium concentration in biofortified mushrooms was 800 times higher compared with control samples grown on wheat straw from non selenium-rich areas (141 vs 0.17 lg Se g À1 dry weight). Seventy-five percent of the selenium was extracted after in vitro simulated gastrointestinal digestion and investigation of the selenium molecular fractions by size exclusion HPLC-ICP-MS revealed that proteins and any other high molecular weight selenium-containing molecule were hydrolyzed to peptides and low molecular weight selenocompounds. Analysis of the gastrointestinal hydrolysates by anion exchange HPLC-ICP-MS showed that the bioaccessible selenium was mainly present as selenomethionine, a good bioavailable source of selenium, which accounted for 73% of the sum of the detected species. This study demonstrates the feasibility of producing selenium-biofortified edible mushrooms using selenium-rich agricultural by-products as growth substrates. The proposed approach can be used to evaluate whether selenium-contaminated plant waste materials harvested from high-selenium areas may be used to produce selenium-biofortified edible mushrooms based on the concentration, bioaccessibility and speciation of selenium in the mushrooms.
Environmental Science and Pollution Research, 2014
The present study was conducted to isolate and explore bacterial strains with a potential to sequ... more The present study was conducted to isolate and explore bacterial strains with a potential to sequester lead (Pb) and tolerate other heavy metals from industrial effluents and sediments. Out of the six bacterial strains isolated from seleniferous sites of Punjab, three isolates (RS-1, RS-2, and RS-3) were screened out for further growth-associated lead sequestration and molecular characterization on the basis of their tolerance toward lead and other heavy metals. Biomass and cell-free supernatant were analyzed for lead contents using ICP-MS after growth-associated lead sequestration studies in tryptone soya broth (pH = 7.2 ± 0.2) under aerobic conditions at 37 °C temperature. Almost 82 % and 70 % divalent lead was sequestered in cell pellets of RS-1 and RS-3, respectively while only 45 % of lead was found in cell pellet of RS-2 in the first 24 h. However, significant biosequestration of lead was observed in RS-2 after 48 h of incubation with concomitant increase in biomass. Simultaneously, morphological, biochemical, and physiological characterization of selected strains was carried out. 16S rRNA gene sequence of these isolates revealed their phylogenetic relationship with class Bacillaceae, a low G + C firmicutes showing 98 % homology with Bacillus sp.
Environmental Science and Pollution Research, 2012
This study evaluates the effect of integrated solarassisted advanced oxidation process (AOP) and ... more This study evaluates the effect of integrated solarassisted advanced oxidation process (AOP) and biological treatment on the extent of degradation of effluents from chlorination (C) and first alkaline extraction (E 1) stages of soda pulp bleaching in agro-residue-based pulp and paper mill. Biodegradation of the effluents was attempted in suspended mode using activated sludge from the functional pulp and paper industry effluent treatment plant acclimatized to effluents in question. The photocatalytic treatment was employed using zinc oxide (ZnO) in slurry mode for decontamination of effluents in a batch manner and the degradation was evaluated in terms of reduction in chemical oxygen demand. The biological treatment (24 h) of C and E 1 effluent resulted in 30 and 57 % of degradation, respectively. Solar-induced AOP of C and E 1 effluents resulted in 53 and 43 % degradation under optimized conditions (2.5 g L −1 ZnO at pH 8.0) after 6 h of exposure. For C effluent, a short duration of solar/ZnO (1 h) prior to biological treatment reduced the time required at biological step from 24 to 12 h for almost same extent (92 %) of degradation. However, sequential biological treatment (24 h) followed by solar/ ZnO (2 h) resulted in 85.5 % degradation. In contrast, in the case of E 1 effluent, sequential biological (24 h)-solar/ZnO (2 h) system effectively degrades effluent to 95.4 % as compared to 84.8 % degradation achieved in solar/ZnO (2 h)-biological treatment (24 h) system. In the present study, the sequencing of photocatalysis with the biological treatment is observably efficient and technically viable process for the complete mineralization of the effluents.
Environmental Progress & Sustainable Energy, 2014
ABSTRACT Heterogeneous photocatalytic degradation and mineralization of Isoproturon (IPU) was inv... more ABSTRACT Heterogeneous photocatalytic degradation and mineralization of Isoproturon (IPU) was investigated in aqueous solutions containing titanium dioxide. The degradation was monitored by observing the change in absorption intensity in UV range and through HPLC analysis. The degradation rate was found to be strongly dependent on catalyst concentration, initial pH, and substrate concentration. The effect of variation in intensity of UV irradiations, catalyst recycling as well as area/volume is also studied for the practical applications. The degradation rate was observed to follow first-order kinetics. TiO2 loading 0.5 g L−1, pH 5.0, C0 = 25 mg L−1 were the optimized conditions for obtaining the better degradation rates. Reduction in COD and TOC values along with the generation of ammonium further indicated the mineralization of the IPU. Fixed bed studies on glass sheet and small cement slabs eliminates the drawbacks of slurry mode photocatalysis. An attempt was also made to identify the intermediates (degradation products) through LC-MS analysis. © 2013 American Institute of Chemical Engineers Environ Prog, 2013
Desalination and Water Treatment, 2012
The study presents a comparative account on TiO 2 and ZnO facilitated photocatalytic degradation ... more The study presents a comparative account on TiO 2 and ZnO facilitated photocatalytic degradation of 4-chlorocatechol (4-CC) typically found in bleach mill effluents (BME). The effect of major process parameters such as catalyst dose, pH, oxidant concentration, and source of light (UV/solar) on degradation efficiency has been investigated. The degradation efficiency of 4-CC was assessed in terms of absorbance as a function of irradiation time. Of the two catalysts screened, ZnO has been observed to be a better catalyst over TiO 2. The maximum degradation of 99.2 and 91.6% was obtained with 1.5 g/L ZnO, at pH 8, after 2 h irradiation and with 2.5 g/L TiO 2 , at free pH (6.5), 0.04 M NaOCl concentration after 6 h irradiation, respectively. Further, the kinetics of degradation process was found to follow pseudo-first-order reaction. The photocatalytic process was applied to treat actual BME and degradation of effluent, observed in terms of chemical oxygen demand reduction, was 36.5 and 39% with UV/TiO 2 /NaOCl and UV/ZnO systems, respectively. A 10-fold dilution of effluent was, however, needed to make the effluent amenable to photocatalytic treatment. Degradation efficiency at optimized conditions under solar mode was almost the same as under UV irradiation, thus demonstrating the commercial viability of the process.
Selenium in agricultural soils of Punjab has come in public attention lately because of reports f... more Selenium in agricultural soils of Punjab has come in public attention lately because of reports from widely divergent backgrounds ranging from research outcome to general awareness campaigns. It was noted that potentially toxic amounts of selenium could be passed on to livestock and human population through fodder and feed resulting in deleterious effects. The present study explores the possibilities of growing Allium cepa (onion) in Se rich soils with an ultimate objective of introducing cultivation of alliaceous species in this region. In addition, work was carried out to examine the anti-oxidant activity of overground (leaves) and underground (bulb and root) tissues. The observations indicate that although the plant growth relatively gets promoted at the initial stages of the tissue formation, further growth is significantly affected by the exposure to both the selenium oxyanions viz., selenate and selenite. The retardation was more prominent in the roots than the above ground tissues viz., bulb and leaves. The distribution of the total selenium was unevenly distributed among the onion tissues. The average uptake of selenium was higher in bulb (maximum of 1173 µg/gm), followed by leaf (maximum of 1040 µg/g) and root (694 µg/g). Bulbing was visible with most of the plants at the eight week of plant sampling, however, but retarded in the case of selenate exposure. The total selenium concentration in leaf and bulb significantly decreased after 90 days of exposure which may be attributed to the volatilization exhibited by the plantlets after accumulation of selenium. The results show that the anti-oxidant activity (TBARS assay) was more prominent in the case of exposure to selenate followed by selenite despite the retarded plant growth in the presence of selenium. The study clearly demonstrates the applicability of A.cepa as a crop for seleniferous soils as a phytoaccumulator as well as a phyto-therapeutic resource.
Acta Alimentaria, 2014
Wheat, an important staple cereal crop cultivated in seleniferous region of India, noted to accum... more Wheat, an important staple cereal crop cultivated in seleniferous region of India, noted to accumulated signifi cantly high concentrations of Se, was examined for the distribution of selenium in various protein fractions of the grains. Amongst the protein fractions, Se was dominantly (33-37%) present in the albumin fraction in Se rich grains followed by other fractions viz., globulin (20-25%), glutelin (20-25%), and prolamin (17-20%). The observations are important in context of exploring the use of this material as functional foods in formulating Se-enriched diets for Se-defi cient population.
International Journal of Recycling of Organic Waste in Agriculture, 2014
Background Majority of the post-harvest agri-residues from agricultural activity in Punjab, India... more Background Majority of the post-harvest agri-residues from agricultural activity in Punjab, India, is burnt in the field resulting in the loss of soil fertility and release of large amounts of air pollutants. In an effort to reutilize the selenium-accumulated waste wheat and paddy straw from seleniferous region of Punjab, two varieties of edible mushrooms, Pleurotus sajor-kaju and Volvariella volvacea, were cultivated on Se-rich wheat and paddy straw, respectively. Results Se concentration in Se-enriched P. sajor-kaju and V. volvacea (43.5 ± 2.1 and 35.0 ± 1.1 lg/g) was significantly higher than control (5.2 ± 1.0 and 5.57 ± 0.07 lg/ g), respectively. The antioxidant activity as depicted by total phenol content, total oxidant activity, DPPH scavenging, metal chelation and lipid peroxidation inhibiting activity of extracts from Se-fortified mushrooms were significantly higher (p \ 0.05 to p \ 0.001) than control mushrooms. Conclusion The increased antioxidant activity is attributed to be induced by the accumulation of selenium by these species of mushrooms, indicating the antioxidant nature of selenium in biological systems. Further, the present study also demonstrates the use of Se accumulated agricultural residues as substrates for producing Se-rich mushrooms as potential sources for Se supplementation/ nutraceutical applications.
Cereal Chemistry Journal, 2015
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Papers by Tejo Prakash Nagaraja