Biomedical subjects

S B Jonnalagadda

Publications and source records attributed to S B Jonnalagadda.

13 recordsLinked to original sources

PubMed2006

Elemental uptake by seaweed, Plocamium corallorhirza along the Kwazulu-natal coast of Indian Ocean, South Africa.

This study reports the elemental uptake by Plocamium corallorhiza, a Rhodophyta class of coralline alga grown richly along KwaZulu-Natal coastline. The uptake of seven important elements, namely Fe, Mn, As, B, Ti, Zn and Hg, selected based on their abundance in the samples, were investigated for a one-year cycle, from June 2002 to May 2003, at four chosen sites located along the KwaZulu-Natal coastline. The sites spread over 150 km from North to South Coast are Zinkwasi, Ballito, Treasure Beach and Park Rynie. P. corallorhiza possess good manganese and arsenic-accumulating ability and has potential to be an excellent indicator for most of the metals studied. A typical P. corallorhiza sample at Park Rynie (winter) recorded Mn (14 ppm), Fe (6.02 ppm), As (8.4 ppm), B (1580 ppb), Zn (234 ppb), Ti (751 ppb) and Hg (15.8 ppb). The general trend found at all sites was a large decrease in iron concentration in spring and summer and increase in winter. Mercury uptake was lowest in winter and autumn at all sites. The highest mercury levels in the seaweeds were recorded during spring or summer.

Arsenic↗

PubMed2006

Elemental distribution in selected Agaricus and Rhizina mushrooms in South Africa.

The levels of calcium, magnesium, iron, manganese, lead, chromium and cadmium in four prevalent mushroom species in South Africa, namely two edible Agaricus bisporus species, one inedible Agaricus xanthodermus species and a poisonous type mushroom, Rezhina undulata are reported. Analytical results from the open vessel and microwave digestion approaches were compared. While higher levels of Ca and Mg were found in the edible types, the inedible and poisonous type mushrooms had relatively high levels of manganese, chromium, cadmium and lead. Agaricus xanthodermus had Ca (204), Mg (660), Fe (306), Mn (30), Cr (16.2), Pb (50.6) and Cd (29.5) mg kg(-1) by dry weight, while Rhizina undulata, which grows on dead wood recorded Ca (121), Mg (517), Fe (130), Mn (30.7), Cr (32.1), Pb (49.5) and Cd (20) mg kg(-1) by dry weight.

Agaricus↗

PubMed2006

Seaweeds along KwaZulu-Natal coast of South Africa-3: elemental uptake by Ulva lactuca (Sea lettuce).

The elemental uptake by Ulva lactuca (Sea lettuce), a marine macro-algae (chlorophyta, green alga) grown richly along KwaZulu-Natal coastline. The total elemental concentrations of seven important elements, namely manganese, iron, arsenic, boron, titanium, zinc and mercury, selected based on their abundance in U. lactuca were investigated for one year cycle (June 2002 to May 2003). The four selected sampling sites, Zinkwasi, Ballito, Treasure Beach and Park Ryrie are spread over 150 km wide along the KwaZulu-Natal coastline from North to South. The Ulva lectuca possess good manganese and arsenic accumulating ability and an excellent bio-indicator for most of the metals studied. A typical U. lectuca sample at Zinkwasi (in winter) recorded Mn (25.3 +/- 1.16 ppm), Fe (21.0 +/- 0.85 ppm), As (6.2 +/- 0.30 ppm), B (935 +/- 14 ppb), Ti (863 +/- 34 ppb), Zn (421 +/- 21 ppb), and Hg (61.3 +/- 1.2 ppb). The general trend found at all sites was high elemental concentrations in winter and a decrease in concentrations from winter to spring and summer. Iron uptake was lowest in summer and autumn at all sites. Ulva lactuca recorded highest mercury levels (>400 ppb) during the spring season at the Treasure Beach site near Durban.

Arsenic↗

PubMed2006

Seaweeds along KwaZulu-Natal Coast of South Africa--4: Elemental uptake by edible seaweed Caulerpa racemosa (sea grapes) and the arsenic speciation.

The elemental uptake by edible seaweed Caulerpa racemosa (Sea grapes), a marine macroalgae (chlorophyta, green alga) grown richly along KwaZulu-Natal coastline. The total concentrations of seven elements, namely Mn, Fe, As, B, Ti, Zn and Hg in Caulerpa racemosa were monitored for a one-year cycle (June 2002 to May 2003) at four selected sampling sites spread over 150 km wide from North to South. The C. racemosa possess high arsenic, boron and titanium accumulating ability, but low iron uptake. A typical C. racemosa sample at Treasure Beach in the vicinity of Durban Metropolis in autumn contained Mn (5.2+/-ppm), Fe (0.21+/-0.01 ppm), As (8.5+/-0. ppm), B (1090+/-ppb), Ti (159+/-ppb), Zn (3.8+/-0.1 ppb), and Hg (189+/-ppb). The general trend found at all sites was high elemental concentrations in winter and a decrease in concentrations from winter to spring and summer. C. racemosa recorded highest mercury levels (>205 ppb) during the summer season at the Zinkwasi site. The arsenic speciation in four abundant seaweeds from the beaches of Indian Ocean in the KwaZulu-Natal coast is investigated. The speciation of arsenic in two rhodophyta seaweeds, Plocamium corallorhiza and Gelidium abbottiorum, and two chlorophyta seaweeds, Ulva lactuca and Caulerpa racemosa at four sampling sites during the summer of 2003, is elucidated. Caulerpa racemosa had highest total arsenic (in ppb) reaching (8850+/-200) at Zinkwasi, and the concentrations of the other arsenic species analysed are As (III) (194+/-10), As(V) (568+/-27), methylarsonic acid (494+/-22) and dimethylarsinic acid (373+/-12). In an indirect estimation, C. racemosa had 81+/-2% aresenosugars.

Arsenic↗

PubMed2005

Heavy metal uptake by two edible Amaranthus herbs grown on soils contaminated with lead, mercury, cadmium, and nickel.

The uptake of an element by a plant is primarily dependent on the plant species, its inherent controls, and the soil quality. Amaranthus hybridus (green herbs) and Amaranthus dubius (red herbs) were chosen to investigate their response and ability to accumulate and tolerate varying levels of elements in their roots and shoots. Red herbs and green herbs were grown in soil pots contaminated with three mixtures of Cd(II), Ni(II), Pb(II), and Hg(II). Plants in the control treatment were grown in the absence of the heavy metals mixture. The distribution of Cd, Ni, Pb, and Hg in the plants (in roots, stems, and leaves) was determined in two stages. Stage 1, after 5 weeks of plant growth and stage 2, full grown after 10 weeks of growth. In the red herbs the Cd concentration in the leaves at stage 2 was 150 ppm and was present in higher concentrations than Ni, Hg, and Pb. At the highest contamination level, in the green herbs plant, Hg was present in the highest concentration in the root, i.e., 336 ppm at stage 1, while the level in the leaves was 7.12 ppm. Both the green and red herbs species showed an affinity for Ni and Cd with moderate to high levels detected in the leaves, respectively.

Amaranthus↗

PubMed2004

A photometric method for ozone determination using alizarin violet.

A photometric method for on-line determination of ozone is reported based on the reaction of alizarin violet with ozone at basic pH 10. The method is applied to determine the concentrations of ozone generated using an ozonizer and is compared with iodide method as guide lined by the International Ozone Association. Alizarin violet reacts with ozone in 6:1 stoichiometric ratio. The method is simple, reliable, and reproducible. Ozone concentrations in the range 1.0-5.0mg L(-1) can be determined on-line with out change in procedure.

Anthraquinones↗

PubMed2004

Heavy metal uptake by spinach leaves grown on contaminated soils with lead, mercury, cadmium, and nickel.

Spinach plants were grown in soil pots contaminated with increasing mixtures of lead, mercury, cadmium, and nickel salts. Plants in the control soil were grown in the absence of the heavy metals mixture. The elemental distribution of Cd, Ni, Pb, and Hg in the roots and leaves of Spinach (Spinacia Oleracea) was determined in two stages, Stage 1, after five weeks of plant growth and Stage 2, after 10 weeks with full growth. Under the influence of contamination of soil with the heavy metal mixtures, Hg was the most accumulated element in the root of the spinach plant with a concentration of 283 ppm recorded in the highest contaminated soil, followed by Cd at 148 ppm.

Cadmium↗

PubMed2003

A user-friendly programme 'SIMKINERSQUO; for simulation of kinetics involving complex reaction mechanisms.

A programme, 'SIMKINERSQUO; is developed using a semi-implicit extrapolation method (SIEM) which uses the implicit midpoint rule and extrapolation to simulate complex mechanisms based on the kinetics of homogeneous chemical systems. The chemical kinetics pre-processor code is designed to translate a user-specified system of chemical rate equations into a system of chemical kinetic differential equations. The developed programme is applied to the 13-step mechanism of the reaction between Nile blue and acidic bromate. The results obtained compare well with the curves drawn using the other method, reported in literature.

Journal Article↗

PubMed2003

Oxidative degradation of indigocarmine by hypochlorite--a tool for determination of hypochlorite in commercial samples.

The oxidative action of hypochlorite on indigocarmine is investigated. Hypochlorite dissociates indigocarmine to produce isatin-5-monosulphonic acid, with a stoichiometry of 2:1. The probable mechanism is proposed. The suitability of reaction between hypochlorite and indigocarmine as an indicator reaction for the determination of high levels of hypochlorite in synthetic and commercial samples is investigated. A simple and reliable kinetic-analytical method is developed for the determination of hypochlorite ion at alkaline pH, based on its oxidizing activity.

Coloring Agents↗

PubMed2002

Seawater in treatment of waste waters.

Hypochlorite which is generated electrolytically from seawater under optimized conditions was evaluated for its (i) bacterial sensitivity to Escherichia coli in comparison to commercial bleaches and (ii) utilization in the treatment of sanitary effluent. Effective bacterial growth inhibition occurs using the hypochlorite containing seawater. Waste water samples from sewage treatment plant, from two sampling points, i.e., one after primary treatment (Sample 1) and the second prior to the discharge of the effluent into the river (Sample 2) were analyzed. Sample 1 was subjected to the hypochlorite treatment and Sample 2 was used to assess the treatment work's efficiency. Quality parameters namely Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Dissolved Solids (DS), Suspended Solids (SS) were monitored at each sampling point. The addition of hypochlorite to sample at point 1 lowered the BOD and COD levels and improved the water quality.

Colony Count, Microbial↗

PubMed2001

Water quality of the odzi river in the Eastern Highlands of Zimbabwe.

For Odzi. the main river originating in the Eastern Highlands of Zimbabwe, the nature, sources and extent of pollution are characterised. Over a span of 9 months, the river water samples collected at six selected sites were analysed for various physical and chemical parameters namely, temperature, conductance, pH, total suspended and dissolved solids, BOD. total phosphate and nitrate levels. The Mutare river carried the seepage from abandoned mine dumps to the Odzi River. Water quality of the Odzi River at different points assessed by the water quality indices (WQI) is compared. According to the quality indices during the study period, water quality in the upper reaches of the river was medium to good. It dwindled in the plains, due to the seepage from abandoned mine dumps and discharges from the farm lands.

Agriculture↗

PubMed1993

Toxicity, bioavailability and metal speciation.

1. Environmental toxicology emphasizes the difference from traditional toxicology in which pure compounds of interest are added to purified diets, or injected into the test animals. When the objective is to study the fate and effects of trace elements in the environment, knowledge of the speciation of the elements and their physico-chemical forms is important. 2. Cadmium salts such as the sulfides, carbonates or oxides, are practically insoluble in water. However, these can be converted to water-soluble salts in nature under the influence of oxygen and acids. Chronic exposure to Cd is associated with renal toxicity in humans once a critical body burden is reached. 3. The solubility of As(III) oxide in water is fairly low, but high in either acid or alkali. In water, arsenic is usually in the form of the arsenate or arsenite. As(III) is systemically more poisonous than the As(V), and As(V) is reduced to the As(III) form before exerting any toxic effects. Organic arsenicals also exert their toxic effects in vivo in animals by first metabolizing to the trivalent arsenoxide form. Some methyl arsenic compounds, such as di- and trimethylarsines, occur naturally as a consequence of biological activity. The toxic effect of arsenite can be potentiated by dithiols, while As has a protective effect against the toxicity of a variety of forms of Se in several species. 4. Selenium occurs in several oxidation states and many selenium analogues of organic sulfur compounds exist in nature. Selenium in selenate form occurs in alkaline soils, where it is soluble and easily available to plants. Selenite binds tightly to iron and aluminum oxides and thus is quite insoluble in soils. Hydrogen selenide is a very toxic gas at room temperature. The methylated forms of Se are much less toxic for the organism than selenite. However, the methylated Se derivatives have strong synergistic toxicity with other minerals such as arsenic. 5. Aquatic organisms absorb and retain Hg in the tissues, as methylmercury, although most of the environmental Hg to which they are exposed is inorganic. The methylmercury in fish arises from the bacterial methylation of inorganic Hg. Methylmercury in the human diet is almost completely absorbed into the bloodstream. The nervous system is the principal target tissue affected by methylmercury in adult human beings, while kidney is the critical organ following the ingestion of Hg(II) salts.

Animals↗

PubMed1982

Flux regulation in glycogen-induced oscillatory glycolysis in cell-free extracts of Saccharomyces carlsbergensis.

To localise the controlling point of the glycolytic system, the temporal changes in concentrations of glycolytic intermediates have been analysed after addition of glycogen to a substrate-depleted yeast extract. Three sequential metabolic states are clearly observable: a transition state at which there is continuous accumulation of the intermediates before the glyceraldehydephosphate dehydrogenase (GAPDH, EC 1.2.1.12) step; a stationary state with all glycolytic intermediates having concentrations oscillating at nearly stationary mean values; and a depletion state at which the intermediates before the GAPDH step are being depleted due to the exhaustion of glycogen. In all these states, the mean ethanol production rate and the concentration of ATP and the intermediates beyond the GAPDH-step are maintained fairly constant, while the glycogen consumption rate and intermediate concentrations of the upper part of the glycolytic system changes considerably: the glycogen consumption rate varies 4-fold and fructose-bis-phosphate concentration more than 10-fold. Doubling of the initial glycogen concentration and the addition of a great excess of fructose-bis-phosphate do not affect the ethanol production rate and the mean glycerate-3-phosphate (3-PGA) and pyruvate levels. By contrast, ethanol production was accelerated by an increase of the net ATP consumption rate resulting from either the addition of apyrase or by substitution of trehalose for glycogen. Neither the mean absolute ATP level nor the adenylate energy charge were measurably affected, however, all this data can be interpreted in terms of a very strong stoichiometric regulation and stabilization of the lower part of the glycolytic system.

Adenosine Triphosphate↗