International Letters of Natural Sciences Vol. 8

Abstract: Human activities including industrialization and agricultural practices contributed immensely in no small measure to the degradation and pollution of the environment which adversely has an effect on the water bodies (rivers and ocean) that is a necessity for life. This paper tries to discuss basically what water pollution is and equally to address the source, effect control and water pollution management as a whole. Some recommendations such as introduction of environmental education were mentioned.

Abstract: This paper presents the study of the tensile properties of Sansevieria trifasciata – fiber (here after called STF) reinforced polyester composites. The composite sample was fabricated with five different fiber lengths of STF (2, 4, 6, 8 and 10 mm). The fabrication was made by hand lay-up technique. Mechanical properties were determined using tensile testing. An interact between fiber and matrix was observed from the SEM (scanning electron microscope) micrographs. The study reveals that the tensile strength increased with fiber length without effecting the elongation at break of the composite.

Abstract: A pot culture was carried out with Oryza sativa L. vari-Co-39, to investigate the effects of supplementary calcium chloride on plants grown at NaCl (50mM) concentration. Treatments were: (1) Control: nutrient solution alone (C); (2) nutrient solution plus 50mM sodium chloride (NaCl); (3) nutrient solution plus 10mM calcium chloride (CaCl₂); (4) nutrient solution plus 15mM calcium chloride (CaCl₂); (5) nutrient solution and 50 mM NaCl plus supplementary 10 mM CaCl₂ (NaCl + CaCl₂); and (6) 50 mM NaCl plus additional mixture of 15 mM CaCl₂ in nutrient solution (NaCl + CaCl₂). The plants grown under salt stress produced low dry weight and relative water content than those grown in standard nutrient solution and in CaCl2 alone. Supplemental calcium chloride added to nutrient solution containing salt significantly improved growth and relative water content. Membrane permeability increased with high NaCl application and these increases in root membrane permeability were decreased with supplementary Ca. The concentration of chloride (Cl) increases highly for all treatments. Sodium (Na) concentration in plant tissues increased in both shoots and roots at high NaCl treatment. Application of supplementary Ca lowered Na concentration. Concentrations of Ca. K and N were at deficient ranges in the plants grown at high NaCl levels and these deficiencies were corrected by supplementary Ca. The ameliorating effect of Ca on growth and physiological variables could reduce the negative effect of salinity of Oryza sativa L., plants.

Abstract: Thirty species of lignicolous fungi belonging to Ascomycetes and Basidiomycete are reported from the Ratanmahal Wildlife Sanctuary, Gujarat, India. The new species are Coriolus versicolor, Coriolopsis gallica, Daedalea quercina, F. resupinate, D. unicplor var. hydnoidea, Fomitopsis rosea, Hypodontia comptopsis and Lenzites betulina. F. varigatum is reported for the first time from India. All the species are new to studied area.

Abstract: Hepatoprotective and antioxidant activity of Lannea coromandelica bark extract (LCBE) was investigated on thioacetamide induced hepatotoxicity in rats. Hepatotoxicity was induced by thioacetamide (TAA) administration (100 mg/kg. s.c). LCBE at different doses (400 and 200 mg/kg) were administered orally to male wistar rats. Thioacetamide caused elevation of serum concentration of AST, ALT, ALP, serum bilirubin and also reduced serum concentration of total protein, albumin, sodium, potassium in animals as compared to control (p < 0.05) but LCBE treated rats showed maximum reduction of AST [(138±5.1) IU/L], ALT [(71 ±2.7) IU/L], ALP [(140 ±1.9) IU/L] with the high dose (400 mg/kg bw) of combined aqueous and alcoholic bark extract. Whereas, serum bilurubin, cholesterol, sugar and LDH content were varied with the treatments but showed higher with the only ethanolic extract at dose of 400 mg/kg. The IC50 value was observed as (83.28 ±2.12) µg/mL, for DPPH radical scavenging activity. Result concluded that ethanolic extract and combined aqueous and alcoholic bark extract of L. coromandelica showed a potential hepatoprotective and antioxidant activities might be due to the presence of phenolic groups, terpenoids and alkaloids.

Abstract: Discharge of metal containing effluents into water has been a cause of major concern. Traditional treatment methods are proving to be ineffective and expensive. Chitosan was studied as a potential biosorbent due to its positive charge and relatively low cost. The study involves evaluating the metal binding performance of chitosan in a Polymer Enhanced Diafiltration (PEDF) system which uses an ultra filtration membrane to retain the chitosan which, in turn, binds the metal, thereby preventing passage into the permeate stream. Conditions for binding such as pH, concentration of polymer and chromium were studied. Optimal performance was obtained when the system was operated at pH values lower than the pKa of chitosan i.e. 6.3. Using 6 g/L chitosan at pH 4.0, chromium concentration was reduced to less than 1mg/L from a feed concentration of 20 mg/L. Equilibrium dialysis experiments were done to study the kinetics of binding and the uptake of metal per gram of polymer. Rheological measurements demonstrated that in the presence of 1-100 mM chromate, chitosan was found to be slightly shear thickening at low concentrations such as 4 g/L and 6 g/L whereas it was slightly shear thinning at higher concentrations like 12 g/L and 20 g/L This suggests that neutralization of chromium anions is due to the interaction of multiple chitosan molecules. This result is consistent with the relatively stiff nature of the polysaccharide. Overall, this study suggests that some modification of the native polymer would be required to improve uptake and make it an industrially workable process.