scholarly journals Development and Application of an Assay for Uranyl Complexation by Fungal Metabolites, Including Siderophores

2003 ◽  
Vol 69 (6) ◽  
pp. 3600-3606 ◽  
Author(s):  
Joanna C. Renshaw ◽  
Verity Halliday ◽  
Geoffrey D. Robson ◽  
Anthony P. J. Trinci ◽  
Marilyn G. Wiebe ◽  
...  

ABSTRACT An assay to detect UO2 2+ complexation was developed based on the chrome azurol S (CAS) assay for siderophores (B. Schwyn and J. B. Neilands, Anal. Biochem. 160:47-56, 1987) and was used to investigate the ability of fungal metabolites to complex actinides. In this assay the discoloration of two dyed agars (one containing a CAS-Fe3+ dye and the other containing a CAS-UO2 2+ dye) caused by ligands was quantified. The assay was tested by using the siderophore desferrioxamine B (DFO), and the results showed that there was a regular, reproducible relationship between discoloration and the amount of siderophore added. The ratio of the discoloration on the CAS-UO2 2+ agar to the discoloration on the CAS-Fe3+ agar was independent of the amount of siderophore added. A total of 113 fungi and yeasts were isolated from three soil samples taken from the Peak District National Park. The fungi were screened for the production of UO2 2+ chelators by using the CAS-based assay and were also tested specifically for hydroxamate siderophore production by using the hydroxamate siderophore auxotroph Aureobacterium flavescens JG-9. This organism is highly sensitive to the presence of hydroxamate siderophores. However, the CAS-based assay was found to be less sensitive than the A. flavescens JG-9 assay. No significant difference between the results for each site for the two tests was found. Three isolates were selected for further study and were identified as two Pencillium species and a Mucor species. Our results show that the new assay can be effectively used to screen fungi for the production of UO2 2+ chelating ligands. We suggest that hydroxamate siderophores can be produced by mucoraceous fungi.

2020 ◽  
Vol 1 (1) ◽  
pp. 25-32
Author(s):  
M N Wekhanya ◽  
P. K. Mbugua ◽  
J. K. Mworia

The aim of this study was to establish whether the invasive plant Lantana camara L. alters the soil chemical properties at Ol-Donyo Sabuk National Park. The key objective was to evaluate the soil nutrient composition in areas invaded by L. camara and how these differ from areas without L. camara. Five study sites were selected by purposeful sampling, out of the existing 10 blocks. Soil samples were collected randomly from L. camara invaded areas and similarly from adjacent areas free from L. camara. The soil samples were subjected to determination of the following nutrients and parameters: pH, potassium (K), calcium (Ca) magnesium (Mg), total nitrogen (N), phosphorus (P), total organic carbon (TOC), manganese (Mn), copper (Cu), iron (Fe), zinc (Zn) and sodium (Na). The data obtained was analysed using Two-way ANOVA test to determine difference in nutrients composition in L. camara invaded and non-invaded areas. Three-way ANOVA test was used to gauge the interactions between wet and dry season, invaded and non-invaded areas and study sites. A post-ANOVA test, Tukey’s Honest Significant Difference was done to separate the means. The results from the study indicated L. camara invaded areas had a significant difference in pH, P, N, Mn, Fe and total organic C compared to the patches that had native plants and not invaded by L. camara. High pH also makes P to be more available to plants that is why P was high in the L. camara invaded areas. This study revealed that L. camara remarkably changes the concentration and balance of soil nutrients resulting to a change in chemistry of soil nutrients. This is in a bid to suit its survival to the detriment of the native plant species. This study is hence vital for designing an effective eradication and preventive strategy of L. camara in Ol-Donyo Sabuk National Park and other protected ecological habitats in Kenya.


1989 ◽  
Vol 121 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Hiroshi Tomita ◽  
Masamichi Ogawa ◽  
Takashi Kamijo ◽  
Osamu Mori ◽  
Eiji Ishikawa ◽  
...  

Abstract. GH values were determined by a highly sensitive sandwich enzyme immunoassay in the 1st morning and/or 24-h accumulated urine samples in 94 children (short stature 70, including 14 with complete GH deficiency, 9 with partial GH deficiency, and 47 with GH-normal short stature; Turner's syndrome, 10, and simple obesity, 14). GH values were also determined in the 2nd to 4th urine samples taken on the same day together with the 1st morning urine in 5 of them. GH values in the 1st morning urine correlated significantly with those of the 24-h urine and with serum peak and mean GH values during nocturnal sleep as a physiological GH secretion test. The 2nd to 4th urines had lower GH concentrations than the 1st morning urine. The GH value of the 1st morning urine in complete GH deficiency was significantly lower than those in GH-normal short stature, partial GH deficiency and Turner's syndrome. However, no significant difference was detected in urinary GH values between complete GH deficiency and simple obesity. We conclude that 1st morning urinary GH estimation may be useful for differentiation of complete GH deficiency from other causes of short stature, but may be difficult for the distinction between complete GH deficiency and obesity with normal GH secretory ability.


2021 ◽  
Vol 13 (14) ◽  
pp. 8006
Author(s):  
Till Schmäing ◽  
Norbert Grotjohann

The Wadden Sea ecosystem is unique in many respects from a biological perspective. This is one reason why it is protected by national parks in Germany and by its designation as a UNESCO World Heritage Site. In biology didactics, there are only a few studies that focus on the Wadden Sea. This work investigates students’ word associations with the two stimulus words “national park” and “UNESCO World Heritage Site”. The survey was conducted among students living directly at the Wadden Sea and among students from the inland. The analysis of the identified associations (n = 8345) was carried out within the framework of a quantitative content analysis to be able to present and discuss the results on a group level. A statistically significant difference was found between the two groups. Overall, results showed that the students made subject-related associations as well as a large number of associations to both stimulus words that could be judged as non-subject-related. In some cases, a connection with the region of residence could be found, but this was not generally the case. Even students’ immediate residential proximity to the Wadden Sea is no guarantee that they have knowledge of the two considered protection terms.


2021 ◽  
Vol 18 (1) ◽  
pp. 74-81
Author(s):  
A.A. Yusuf ◽  
O.A. Jayeola ◽  
I.O.O. Osunsina ◽  
G.A. Dedeke

The desire to shore up the shortfall in protein supply, the increased awareness of the importance of cholesterol free animal protein, like guineafowl, and the need to conserve their wild genes, have necessitated studies on improved captive breeding of feral helmeted guineafowl. Hence, this study was aimed at determining the effects of ecological zones and storage systems on the guineafowl eggs. Guineafowl eggs (n=214), were collected from identified and monitored-nests within the Kainji Lake National Park (KLNP) and Old Oyo National Park (OONP). Out of 91 eggs collected from KLNP, 32 and 38 were stored at room temperature (RT-21-25°C) and refrigerator (RF-17-20°C), respectively for five days prior to incubation while 21 eggs were not stored (NS-27-29°C), and out of 123 collected from OONP, 70 and 19 were stored for five days prior to incubation at (RT-21-25°C) and (RF-17-20°C), respectively while 34 eggs were (NS- 27-29°C). Prior to incubation, eggs were weighed, the height and width were measured. The process was repeated after incubation for unhatched eggs. Candling was done three days before hatching at day 29 of egg incubation. Embryo status of unhatched eggs was determined by cracking the eggs. Descriptive and inferential statistics were used to analyse the data. The NS eggs from Kainji (7.60%) and Oyo (2.01%) had the lowest percentage shrinkage in weight across the three storage systems. The order was reversed in height with RF eggs from Kainji (0.96%) and Oyo (0.46%) having lowest. The least shrinkage in width of eggs from Oyo was recorded in the RF eggs (0.00%) and in NS (0.59%) from Kainji. Eggs candling showed that presumed fertile (opaque) was highest (69.10%) in NS eggs followed by RT (45.00%). There was no significant difference (p>0.05) between the hatchability of eggs from the two parks though hatchability (7.60%) of Kainji eggs was higher than those of Oyo (7.40%). Further check on fertilization after incubation showed that RT (37.50%) eggs from Kainji were fertilized but were unable to hatch alive so also was RF eggs (21.10%). The study showed that the eggs sizes vary with ecozones while size of the eggs and storage systems affects hatchability and survival of feral helmeted guineafowl eggs in captivity. Keywords: Guineafowl; ecozones; storage systems; incubation; candling; hatchability


2010 ◽  
Vol 34 (5) ◽  
pp. 1527-1534 ◽  
Author(s):  
João Tavares Filho ◽  
Graziela Moraes de Césare Barbosa ◽  
Adriana Aparecida Ribon

A by-product of Wastewater Treatment Stations is sewage sludge. By treatment and processing, the sludge is made suitable for rational and environmentally safe use in agriculture. The aim of this study was to assess the influence of different doses of limed sewage sludge (50 %) on clay dispersion in soil samples with different textures (clayey and medium). The study was conducted with soil samples collected from native forest, on a Red Latosol (Brazilian classification: Latossolo Vermelho distroférrico) loamy soil in Londrina (PR) and a Red-Yellow Latosol (BC: Latossolo Vermelho-Amarelo distrófico) medium texture soil in Jaguapitã (PR). Pots were filled with 3 kg of air-dried fine earth and kept in greenhouse. The experiment was arranged in a randomized block design with six treatments: T1 control, and treatments with limed sewage sludge (50 %) as follows: T2 (3 t ha-1), T3 (6 t ha-1), T4 (12 t ha-1), T5 (24 t ha-1) and T6 (48 t ha-1) and five replications. The incubation time was 180 days. At the end of this period, the pots were opened and two sub-samples per treatment collected to determine pH-H2O, pH KCl (1 mol L-1), organic matter content, water-dispersible clay, ΔpH (pH KCl - pH-H2O) and estimated PZC (point of zero charge): PZC = 2 pH KCl - pH-H2O, as well as the mineralogy of the clay fraction, determined by X ray diffraction. The results showed no significant difference in the average values for water-dispersible clay between the control and the other treatments for the two soil samples studied and ΔpH was the variable that correlated best with water-dispersible clay in both soils.


Author(s):  
E.A. Omudu ◽  
E.U. Amuta

Domestic environmental pollution resulting from urban livestock farming was investigated in Makurdi using parasitological techniques. The test tube flotation technique was used for the parasitological analysis of animal faecal matter and soil samples collected from residential premises. Ectoparasitic fauna of dogs, goats, sheep and cattle cohabiting with humans within the same residential compound were also collected and identified. The hand-picking and body brushing methods were employed to search for ticks, fleas, lice and mites. Of the 150 soil samples examined, 55 (36.7 %) were positive for 1 or more eggs of helminth parasites. There was no significant difference in the distribution of eggs in the soil samples from the 3 areas sampled (c2=0.046, df=2, P>0.05). Ascaris species were the dominant parasite eggs found. Of the 180 faecal samples examined, 107 (59.4 %) were positive for 1 or more eggs of helminth parasites. Chi-square analysis showed no significant difference in the level of infection of different animal faeces sampled (c2=5.74, df=4, P>0.05). Ascaris species were again the dominating helminth parasite eggs found. There was also no significant difference in the prevalence of helminth eggs in the animal faecal samples from the 3 areas sampled (c2=5.99, df=4, P>0.05). A total of 1908 ectoparasites was recovered (ticks: 32.80 %; lice: 22.43 %; fleas: 22.06% and mite: 22.69 %). There was no significant difference in infestation animals between sexes (c2=0.10, df=4, P>0.05). The predominant genus encountered for ticks were Amblyomma, while Linognathus (43.90%), Ctenocephalides (97.38%) and Sarcoptes (58.89 %) were most predominant for lice, fleas and mites respectively. The public health implications of the findings, especially as these relate to the increasing incidence and prevalence of zoonotic infections, are discussed.


Author(s):  
Naranun Khammanee ◽  
Yanling Qiu ◽  
Nipapun Kungskulniti ◽  
Anders Bignert ◽  
Yuan Meng ◽  
...  

Organochlorine (OCPs) and organophosphorus pesticides (OPPs) have been intensively applied in rice paddy field farming to control pest infestation and increase the yield. In this study, we investigated the presence of organochlorine and organophosphorus pesticides in paddy rice and soil from rice plantations in Thailand and China. According to concentration and distribution of OCPs, the most abundant OCPs residues in rice and soil from Thailand and China were dichlorodiphenyltrichloroethane and hexachlorocyclohexanes. The OPPs of methidathion, carbophenothion, chlorpyrifos, and diazinon were common to Thailand and China in both types of samples. The detection frequency of multiple types of these pesticides was greater than 50% of total samples. The relative concentration of some OPPs residues in rice and soil from Thailand and China were significantly different from each other (p < 0.0083), whereas, no significant difference was observed for the relative concentration of OCPs residues in rice and soil from both countries, except for HCHs (p < 0.05). Bioaccumulation factors of OCPs between rice and soil samples indicated that OCPs and OPPs in soil could accumulate in rice. The carcinogenic and non- carcinogenic risks of OCPs and OPPs seem to be in the safe range as recommended by the European Union.


2021 ◽  
Vol 8 ◽  
Author(s):  
Justine Richaume ◽  
Adrien Cheminée ◽  
Pierre Drap ◽  
Patrick Bonhomme ◽  
Frederic Cadene ◽  
...  

Imaging the marine environment is more and more useful to understand relationships between species, as well as natural processes. Developing photogrammetry allowed the use of 3D measuring to study populations dynamics of sessile organisms at various scales: from colony to population. This study focuses on red coral (Corallium rubrum), as known as precious coral. Metrics measured at a colony scale (e.g., maximum height, diameter and number of branches) allowed population understanding and a comparison between an old (Cerbère-Banyuls reserve) vs. a new (Calanques National Park) MPA. Our results suggested a 5-year time step allows the appearance of a significant difference between populations inside vs. outside the Calanques National Park no-take zones. Red coral colonies were taller and had more branches inside no-take zones. A significant difference was still observable for the populations inside the Cerbère-Banyuls reserve after 40 years of protection, reflecting the sustainability and effectiveness of precautionary measures set by the reserve. The impacts at the local level (mechanical destruction) and those presumed to occur via global change (climatic variations) underline the need to develop strategies both to follow the evolutions of red coral populations but also to understand their resilience. Photogrammetry induced modeling is a time and cost effective as well as non-invasive method which could be used to understand population dynamics at a seascape scale on coralligenous reefs.


2020 ◽  
Vol 6 (2) ◽  
pp. 398
Author(s):  
Aytaç Karakaş ◽  
Hasan Genç

Environmental education in national parks is equivalent to an open and permanent education process in which individuals and communities become aware of their natural environment and gain a critical and sensitive attitude towards it and the use of its resources. The aim of this study was to examine the attitudes of teachers towards national parks who work in schools near different national parks in terms of different variables. As a work of descriptive research, it was conducted with a total of 167 teachers who worked in schools around Kovada Lake National Park, Kızıldağ National Park, and Honaz Mountain National Park. In the study, an attitude scale with a Cronbach’s Alpha coefficient of 0.83 and consisting of 32 items was used for the national parks. The SPSS (Statistical Package for Social Sciences Program) was used to evaluate the data obtained. A T-test and a one-way ANOVA test were used to analyze the data. According to the results obtained, teachers’ attitudes towards the national park did not show a significant difference in terms of their gender, their tenure, the branches they serve, their purpose of visiting the national park, their opinions on the importance attached to the national park, the different schools near the national park, the national park near the schools they worked in, their purpose in visiting the national park previously while they differed significantly according to whether the teachers had visited the national park before.


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