Background: The selection of plant species with phytoremediation potential is as essential as microorganisms are for the success of decontamination programs of areas affected by organic exploration and oil production spills. Based on a greenhouse study aimed at assessing the initial growth of three plant species [Mamona (Ricinus communis), Acácia (Accia holocerisea) and Mimosa (Mimosa caesalpiniifolia)] grown in the presence and absence of crude oil (petroleum), a study was carried out in order to isolate and select filamentous fungi which have potential to grow and degrade this contaminant.
Results: After a growth period of 47 days of the plants, soil samples were collected for treatment, and only comparisons between the contamination effects on the number of colony-forming units (CFU) of species and genera of fungi isolates were evaluated by the Student’s t test. The presence of oil in the soil significantly decreased the number of CFU (44.39 x 103 vs. 8.83 x 102) and, consequently, the diversity of soil fungi. Two hundred and thirteen filamentous fungi were isolated from contaminated and uncontaminated soil samples. In uncontaminated soil, 12 genera and 29 species were identified, whereas in contaminated soil eight genera and 12 species were identified. Penicillium was the most frequent genus found in uncontaminated soil; however, it was not isolated from contaminated soil.
Conclusion: The existence of species that grow with or without the presence of oil allow inferences on their use as an contamination indicator or on how these hydrocarbons are degraded, having po-tential for the treatment of environments.
Central Sudan has recently attracted scientific and socio-economic attention that stimulated active research interest in various research organizations both local and international. Both short and long term research-plans have been launched in order to establish a database that helps developmental policies to improve human lives and apply rational approaches to deal with changes that are indicated by wide-spread ecological disturbance. The research work in this study had been carried out in arid/semi-arid regions of Central Sudan, between latitudes 12º 43′ – 17º 34′ N and longitudes 30º 14′ - 36º 15′ E. This study was undertaken to explore and document quantitative and qualitative ecological setting of the prominent herbaceous medicinal herbs that are indigenous in North, West and East Central Sudan. The parameters measured were: frequency, density, cover and Importance Value Index, specific association of species as index of species diversity and species evenness (equitability), physical and chemical characteristics of the soil, and climatic elements such as rainfall, relative humidity and temperature. Variations within distribution, productivity of each of the candidate species are seemingly related to availability of favorable environmental conditions in each of the three habitats (regions). A major objective of active research programs is to outline work-plans that facilitate strategies for management of natural vegetation and conserve biodiversity.
The effect of crab chitosan on the susceptibility of Staphylococcus aureus (ATCC 12598) was studied in samples of chitosan prepared from shells of whole crab, carapace, leg and claw. S. aureus maintained at a cell density of 7.9 x 105 cfu/ml in phosphate buffered saline (0.001M and pH 6.4) were susceptible even upon 1hr exposure to chitosan at a concentration of 0.05% (w/v) and reduced considerably on 6hr exposure. Among the different chitosans tested, chitosan from crab leg shell was more effective than those from claw shell and carapace. The cell density reduced to
Acute toxicity experiments for Fenvalerate technical grade and 20% EC formulation were conducted using static renewal bioassay and continuous flow through systems for 24h, 48h and 96 h on the three major carps, Labeo rohita, Catla catla and Cirrhinus mrigala. Although toxicity studies were conducted on both fry and fingerling stages, further experiments were carried out with fingerling stages only. After determining the LC50 concentrations for the three fish individually, one-tenth of the 24 h LC50 was taken as sublethal concentration for studies on oxygen consumption. The toxicant exposed fish showed anomalous behaviour like surfacing phenomenon, irregular, erratic and darting swimming movements, hyperexcitability, loss of equilibrium and hitting to the walls of the test tank before finally sinking to the bottom just before death. Oxygen consumption studies for a period of 12 hours, at intervals of 2 hours, in both sublethal and lethal concentrations indicated that lethal concentrations had profound effect than sublethal concentrations and 20% EC was found to be more deleterious than technical grade of fenvalerate. During experimentation, severe respiratory distress, rapid opercular movements leading to the higher amount of toxicant uptake, increased mucus secretion, higher ventilation volume, decrease in the oxygen uptake efficiency, laboured breathing and gulping of air at the surface were observed in all the three carps studied.
The culture of microzooplankton Tintinnopsis cylindrica under controlled conditions is offering within a short period. The microzooplankton is ideal food for the prawn and fish juveniles in the nursery phase and the nutrivite value of the microzooplankton depends on the such as chlorella marina, the microzooplankton Tintinnopsis cylindrica has high reproductive capacity in the tropical water. The short generation period within week and the high nutritive values and the ability to live and grow in the crowed population are the positive features of Tintinnopsis cylindrica and hence, preferred for mass culture under intensive laboratory controlled condition the present study deals with mass culture of microzooplankton, Tintinnopsis cylindrica, under laboratory condition and intensive monitoring of the water quality (management) and species density during culture days.
The present study was carried out to assess the antibacterial activity of bacteria associated with Polychaetes. Polychaetes were collected from the coastal environment and the bacterial communities associated with the surfaces were isolated using traditional culture method. Four biofilm bacteria (Galionella sp., Alteromonas sp., S.aureus, Klebsiella sp.) isolated from the marine water was used as target organism for screening. Three surface associated bacteria were isolated from the surface. The EPS of the three surface associated bacteria were isolated and tested for their antimicrobial activity. The results showed that higher activity against Alteromonas sp. The bioactive compounds were separated by thin layer chromatography. The results showed higher activity against Alteromonas sp. Based on the study, it can be concluded that bacteria associated with Polychaetes would serve as a potential source for the isolation of bioactive compounds.
The present study deals with the Impact of industrial effluents and sewage on river Thamirabarani. Water samples were collected from 5 different river and canal stations such as Melapalayam canal, Palayam canal, Kottur canal, Kandiyapperi canal, Vannarpet and different chemical parameters such as colour, pH, dissolved solids and microbial study of the samples were analysed. The tests showed that the samples of Melapalayam is more polluted in all parameters. Fluoride was found normal in all sites. TDS and Turbidity in Melapalayam canal, Palayam canal and kandiyaperi canal found more. Sites I, II and III are highly bacteriologically contaminated. It was concluded that the samples of river water were polluted mostly and associated with industrial effluent and sewage discharge.
Six swimming pools within Ilorin metropolis were analysed after treatment prior to use by bathers and after use in order to determine their physicochemical and microbiological parameters. These swimming pools were Kwara hotel both adult and children swimming pools, Bekandims, Stella, Kingstone and Successxs swimming pools. The pH ranged from 4.8 to 6.9 and 4.9 to 7.6 before and after use by bathers respectively. Residual chlorine also ranged from 8.95 to 11.08 ppm and 7.17 to 10.08 ppm before and after use by bathers respectively. The total bacterial count ranged from 2.0 to 2.8×103cfu/ml and1.4 ×102 cfu/ml to 3.0 ×103 cfu/ml before and after use respectively. Faecal coliform counts ranged from zero to 4 cfu/ml and zero to 6 cfu/ml before and after use by bathers while their corresponding values of total coliforms were zero to 200 cfu/ml and 4 to 300 cfu/ml respectively. T-test statistical analysis showed that there were significance between the total bacterial count and the free residual chlorine contents of the pools water before and after use by the bathers. A total of thirteen bacterial species viz: Enterobacter aerogenes, Staphylococcus aureus, Pseudomonas sp., Bacillus sp., Streptococcus sp., Micrococcus luteus, Aeromonas aerogenes., Aerococcus sp., Lactobacillus sp., Klebsiella sp., Citrobacter freudii., Corynebacterium sp., and Escherichia coli were isolated. The possible sources of contaminations were identified and mitigation measures highlighted.
Morus alba L. is an economically important plant used extensively in sericulture, also possessesing medicinal properties. In vitro culture provides an effective means to overcome the common problems encountered in conventional propagation by stem cuttings and seeds. Effect of phytohormones, growth adjuvants, sugars and essential minerals on the in vitro response of M. alba explants has been described in the study. Phytohormones and growth adjuvants resulted in explicit response in terms of organogenesis. Sucrose and glucose containing culture media elicited best response among sugars in nodal explants. Typical symptoms were exhibited by the growing shootlets when the medium was deprived of essential minerals such as nitrogen and sulphur.
