Physicochemical Element Research Articles

Novel Insights into the Bioactive Metabolites of Macrocybe gigantea (Agaricomycetes), Using Gas Chromatography-Mass Spectrometry Combined with Chemoinformatic Approaches.

Macrocybe gigantea is an edible mushroom and has multiple pharmacological properties, including antibacterial, antioxidant, and antitumor activities. However, only a few reports are currently available on the bioactive compounds and bioactivity of this mushroom. Therefore, the present study aimed to explore the unique chemical diversity of the fruiting body of M. gigantea. Species identification was done accurately with morphological and molecular methods, followed by mycochemical extraction in different solvent systems. The ethanolic extract of the fruiting body gave maximum yield, and gas chromatography-mass spectrometry (GC-MS) analysis was performed along with an assessment of antibacterial activity and cell viability by the MTT assay. The GC-MS analysis revealed 50 metabolites, and further cheminformatics analysis of these metabolites revealed their possible biological activities. In addition, the physicochemical and mineral element analysis of M. gigantea revealed the quality and authenticity of the species. Altogether, the current investigation gives a comprehensive overview of the bioactive metabolites of M. gigantea.

Trace Element Status and Environmental Implications of Soils and Zea mays from Farmed Dumpsites in the Bamenda Metropolis, North-West Cameroon

This study assessed some physicochemical and trace element properties of soils and Zea mays from farmed dumpsites in the Bamenda metropolis, North-West Cameroon. The growth in population and metal workshops in Bamenda has resulted in the dumping of large quantities of wastes on agricultural soils. Thus, the fear of these agricultural soils and crops being contaminated by waste dumped on them is a call for concern because most of the populations rely on agriculture for survival. A soil and Zea mays sample each was collected from three farmed dumpsites (Nkwen, Mankon, and Bamendakwe) in the Bamenda metropolis and analyzed for physicochemical and trace element properties using standard procedures. The results of physicochemical analysis revealed that the soils had pH values ranging from 5.63 to 7.49, average organic matter, low total nitrogen, high C/N ratio, and high CEC, and the soil textural class was clay loam for soils of Nkwen and sandy loam for soils of Mankon and Bamendakwe. The content of bases in Zea mays was high compared to those in the soil. The concentration of Fe (14635.6 µg/g) in soils of Bamendakwe and Cu (157.17 µg/g) and Zn (1438.36 µg/g) in soils of Mankon had values which were above the permissible limit. The concentration of Zn (114.48 µg/g) in the plant sample of Mankon together with the concentration of Fe in all three plant samples had values above permissible limits. Natural origins and domestic waste were identified as the major sources of trace metals in the soils. Thus, there are potential health hazards related to consuming crops from such soils. Bioremediation techniques can be used to recover heavy metals from such soils. Furthermore, the mobilization of nutrient ions and immobilization of heavy metals by induced liming could be important in sustainable agricultural production and soil environmental protection of the soils studied.

SIAM WEED (Chromolaena odorata) AND COWDUNG COMPOST EFFECTS ON PHYSICOCHEMICAL PROPERTIES, YIELD and MINERAL NUTRITION OF TOMATOES(Lycopersicon esculentum L)

Greenhouse trials were conducted to evaluate the effects of siam weed (chromolaena odorata) and cowdung compost on physicochemical properties, yield and mineral nutrition of tomatoes(lycopersicon esculentum l). The nutritional value of tomato makes it one of the crop that is a daily household consumption by every family.Compost was prepared in this study from Siam weed (Chromolaena odorata) and cowdung. Three compost samples were prepared from Cowdung and siam weed at ratio 100g: 100g (sample A), 200g chopped siam weed (sample B) and 200g cowdung (sample C). These three samples were composted in plastic drums perforated for aeration and each sample was replicated three times. The content in the drums were regularly turned and monitored at 1, 10, 30 and 60 days for physicochemical properties. The physicochemical and mineral element analyses of the compost were carried out using standard procedures.The pH of the composted samples ranged between 5.8 to 6.9. Nitrogen, phosphorus and potassium contents increased with days of composting while those of heavy metals decreased. The result of plant height for the two varieties ranges between 5.31-119.8, number of fruits is between 11-21 and the yield (kg) parameter ranges between 0.76-1.91. Treatment. A gave higher mineral element over other treatment applied. The order of mineral elements contributed to the fruits were as follows treatments A>C>B>D
 

WATER QUALITY OF THE KEBIR WATERSHED, NORTHEAST OF ALGERIA

Water is a natural resource indispensable not only for the maintenance of human life and health but also for the preservation of all ecosystems and economic activities. At the global level, water is threatened in its quality and quantity by various pollutions such as uncontrolled urban and industrial wastes, excessive use of chemical fertilizers and pesticides in agriculture and the exploitation irrationality of this resource. Water quality in Kebir River has been adversely affected by pollutants usually without any treatment. Chemical and physical degradations are due to agricultural and industrial practices and domestic wastewaters. The aim of the present study is to evaluate water quality of the Kebir and Bougous rivers. The physicochemical parameters are analyzed by using the Titrimetry standard procedure and a Spectrophotometer device. The observed values of different physical and chemical parameters like temperature, pH, electrical conductivity, dissolved oxygen, chloride ions, calcium, magnesium, sulfate, nitrite, nitrate, and ammonium have been also performed. Water is sampled at three study sites with four surveys during 2015 and 2016. The results show the existence of a seasonal variation of the physicochemical element concentrations. Also, there is an eutrophication caused mainly by chemical fertilizers used for agriculture. The present findings alert the inhabitant’s sanitation of irrigation water and environmental hygiene, where water quality varies from a moderate pollution state at some sampling stations to a very strong pollution downstream. The used parameters can also be useful when searching deeply for pollution causes and when planning preventive measures for protective purpose.

Prediction of the impact sensitivity of aluminized explosive mixtures using the response surface methodology

The possibility of the impact sensitivity prediction based on the physicochemical properties and element composition of explosives contributes to a faster research of novel high explosives (HE), reduces the research costs and helps to improve the explosive safety. This paper analyzes the existing methods for the prediction of impact sensitivity and introduces a response surface methodology (RSM). The new method comprises a correlation between impact sensitivity and two primary properties of HE: detonation velocity and heat of detonation. Calculated impact sensitivities are compared to the experimental values taken from the literature in order to validate the approach.

Secondary steel mill slags with pulp and paper mill solid residues for soil amendment: mineralogy, relevant physicochemical properties and trace element availability

Inter-industrial utilisation of solid residues for soil amendment was investigated by combining secondary steel mill slags with residuals from a pulp and paper mill. Sample analysis included mineralogical characterisation by X-ray diffraction, relevant physicochemical properties and trace element availability by the original three-stage sequential BCR extraction procedure (CH3COOH, NH2OH·HCl and H2O2 + CH3COONH4) and residual fraction determination by acid digestion (USEPA 3051A). Respectively, the pseudo-total concentrations of trace elements were determined according to USEPA method 3051A. Consequently, the alkalinity of the samples (pH values 12.1–12.2) suggests significant buffering and acid neutralisation capacity with liming effect values (34.9%–35.6%, Ca-equivalents, d.w.) comparable to commercial ground limestone. This was supported by XRD, which only revealed the existence of portlandite [Ca(OH)2] an calcite [CaCO3]. Additionally, the pseudo-total concentrations of trace elements were lower than the respective limit values for EU soil improvers (2006/799/EC). However, Ba and V recovery during sequential extraction (Ba: 40.1–56.0 mg·kg–1, d.w., by CH3COOH; and V: 72.2–96.5 mg·kg–1, d.w., by NH2OH·HCl) indicates potential phytoavailability.

A comparison of sequential extraction procedures for fractionation of arsenic, cadmium, lead, and zinc in soil

Abstract Twelve soil samples differing in physicochemical properties and total element contents were extracted by three sequential extraction procedures to determine As, Cd, Pb, and Zn bound to individual soil fractions and are defined by individual operational procedures. In the case of arsenic, two additional sequential extraction schemes were designed entirely for fractionation of soil containing arsenic were tested. The results confirmed that determination of element proportions bound to individual soil fractions is strongly dependent on the extracting agent and/or procedure applied within individual extracting schemes. As expected, absolute values of the elements released among the individual extracting procedures are weakly comparable. More reliable results were determined for the more mobile soil elements i.e. cadmium and zinc, in the fractions characterizing the most mobile proportions of investigated elements where significant correlations with basic soil characteristics were observed. In contrast, ambiguous results were observed for As and Pb, for both the individual extraction procedures and the effect of the soil characteristics. Regardless of the studied element, the poorest results were determined for reducible and oxidizable soil fractions. The application of at least two independent procedures or modification of the extraction scheme according to element investigated and/or particular soil characteristics can also be helpful in definition of element pattern in soils in further research.