Physicochemical parameters and heavy metal content of the Cross River at Afikpo North Local Government Area were determined using standard analytical methods. Four sampling stations were selected along the river and sampled during March to October, 2004. Parameters determined include chloride, conductivity, salinity, ammonium ion, turbidity, pH, dissolved oxygen (DO), biological oxygen demand (BOD5) and total hardness as well as concentration of some heavy metals (Fe, Pb, Cd, Cu, Ni and Zn) in both water, fish and sediment samples. Concentration of heavy metals was determined by atomic absorption spectrophotometry while Na and K were estimated by flame photometry. The river was slightly acidic in Station 1 (pH 6.80) and slightly alkaline in Station 4 (pH 7.47). Turbidity ranged from 16 FTU (in Station 4) to 22.0 FTU (in Station1) with a mean value of 19.250 FTU. The dissolved oxygen range of 5.16 (Station 2) to 8.0 (Station 4) ensures the survival of aquatic organisms. Iron was the most abundant metal both in sediment (99.78 mg/kg), fish (11.45 mg/kg) and water (4.85 mg/L). Cadmium had the lowest concentration in water (0.19 mg/kg) while Zn and Ni had the lowest concentrations in fish (0.18 mg/kg) and sediment (1.55 mg/kg), respectively. Generally the heavy metals had significantly higher (p
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Crude extracts of three plants Citrullus colocynthis, Leucas aspera, and Strychnos nux-vomica were screened for their larvicidal activities against the third instar of Culex quinquefasciatus. The mortality rate of the mosquito larvae was evaluated against the three botanicals at different periods of exposure (24h, 48h, and 72h). Hexane, Chloroform and Ethyl acetate were used as solvents for the crude extracts. C. colocynthis showed the maximum larvicidal effect (100% mortality) in 750 ppm and 1000 ppm in hexane extract at 24h period of exposure. L. aspera also showed the same activity in hexane extract at 24 h, while S. nux-vomica showed slightly lower effect.
Pesticide pollution in aquatic environment brings about sudden and drastic changes in aquatic organisms. The indiscriminate use of pesticides in agricultural operations affects the aquatic environment to a greater extent. Pesticides like endosulphan and monocrotophos which are widely used in agriculture affect fish population drastically. In the present study the effect of monocrotophos on the enzymes Acid Phosphatase, alkaline phosphatase and lactate dehydrogenase of Ctenopharygodon idella has been estimated. The activity was found to be decreased significantly due to Pesticide intoxification.
Safety of researchers in life and natural sciences is of paramount importance especially in university setting. This research aim at investigating knowledge, awareness and compliance of student researchers to laboratory safety procedures. A three section questionnaire was administered to students undergoing postgraduate training. Section A consists of 11 socio-demographic information. Section B however consist of 14 likert-scale questions on knowledge and awareness of basic laboratory safety procedure while section C consists of 12 likert - scale questions on compliance with safety practices in the laboratory. Thirteen volunteer students from six different laboratories took part in this study. Retrieved questionnaires were statistically analyzed. Analyzed result obtained showed that 61.5% (n=8) were MSc students, 38.5% (n=5) PhD students and spend an average of 5 hours in the laboratory every day. 38.5% (n=5) respondent were international students, 61.5% (n=8) local students and they are at least in the second year of their studies. 62% are aware and have the knowledge of laboratory safety practices. However, 80% of respondents are compliant to these procedures. All respondents wash their hands after working in the lab. 61.5% (n=8) often disinfect their workbenches before and after working. 38.5% (n=5) always wear their lab coat and 69.2% wash their lab coat every month. 53.8% (n=7) work with disease causing microorganisms in the lab. It can be concluded from this study that more awareness needs to be created and compliance strictly mandated for postgraduate researchers especially those working with pathogens as some do not comply with these safety procedures.
In recent years, medical science has turned to a variety of new products and technologies to halt the spread of infections. The most effective and promising antimicrobial agents being embraced by modern medical science today is silver, which is also one of the oldest. In 1940s breakthroughs in antibiotics such as penicillin, actinomycin and streptomycin, medical science began to shift its attention away from preventative compounds such as antimicrobial silver and focused instead on antibiotic treatments. With increasing drug-resistance and growing concern regarding the over-prescribing of antibiotics, there has been a resurgent interest in the use of antimicrobial silver. Unlike antibiotics, silver appears to be immune to resistance. Thus, the conjugation of antibiotic with AgNP (Silver nanoparticles) would prevent development of resistance by microbes and enhance the antimicrobial property of the antibiotic. This study is based on the synergistic effect of Cephalexin antibiotic with AgNP. The nanoparticles were evaluated for their increased antimicrobial activities with Cephalexin antibiotic against E.coli and S. aureus. The antibacterial activity of Cephalexin was increased in the presence of AgNPs against test strains. The results showed that the combination of antibiotics with AgNPs have better antimicrobial effects.
Thuja orientalis L. (Cupressaceae) is an evergreen ornamental garden plant. Its medicinal value is also a well known fact in the literature. The larvae of the evergreen bagworm Thyridopteryx ephemeraeformis feed voraciously on the green foliage of Thuja orientalis and construct protective bags by fastening the eaten up branches of the plant together with silk secreted by the larvae. Brown elongated bags are frequently observed hanging from the branches. Plants usually are completely defoliated and weakened that deteriorates their ornamental as well as medicinal value and it becomes a great concern to the gardener.
Background: Bacteria communicate with each other via chemical signals to coordinate expression of specific genes in a cell density dependent fashion a phenomenon called quorum sensing and response. Pseudomonads are ubiquitous bacteria that are common inhabitants of rhizosphere; these stimulate plant growth by facilitating either uptake of nutrients from soil or producing certain plant growth promoting substances. Besides, these bacteria also prevent proliferation of phytopathogens and thereby support plant growth.
Challenges: The present study deals with the quorum sensing mechanism which influences the antifungal activity of Pseudomonas aeruginosa and Pseudomonas fluorescens strains against the Rhizoctonia solani. The antifungal activity of the Pseudomonas aeruginosa and its extract was tested. The plant growth promoting ability was then analyzed and compared. Seed germination assay was also performed for proving quorum sensing.
Conclusion: Quorum Sensing in Biocontrol and Plant Growth Promoting Properties of Pseudomonas sp. was evaluated and found to be satisfactory.
Background: Aspergillus spp. is an important cause of food degradation and biodeterioration, in addition to being pathogenic to animals. Moreover, some species are used in biotechnology and can produce mycotoxins. This paper reports the use of CREA compounds combined with three alternative pH indicators for the Aspergillus systematics. CREA was added to the basal medium with different pH indicator combinations (bromocresol green and bromothymol blue).
Results: Among the 16 Aspergillus isolates, no difference was observed in the three conditions tested in CREA medium, using different pH indicators. A. ostianus, A. sydowii and Aspergillus sp showed good growth and sporulation. Aspergillus niger 1 and A. niger 2 reacted within three days of growth. As for A. carbonariuns and A. nidulans, they reacted in 5 days. Additionally, Aspergillus sp showed a delayed reaction on the tenth day. When considering the intensity relation of the reaction among the five positive isolates, A. niger 1 and A. niger 2 presented a larger and distinct zone around the colony.
Conclusion: Bromocresol green and bromothymol blue are easy to prepare, and they are recommended for diagnostic purposes in Aspergillus, specially the Nigri section.
Vascular Cambium, a meristem responsible for the formation of wood by way of growth and divisions of its components i.e. ray and fusiform initials were analyzed during different months over two consecutive years in order to assess their impact on growth in Populus nigra from temperate climate of Kashmir Himalaya. The maximum and minimum dimensions of fusiform initials and ray initials were in winter and summer seasons respectively while the horizontal and vertical diameters of ray initials were maximum and minimum in summer and winter seasons respectively.
The Jammu and Kashmir state is stretched between 32°17′-37°03’N latitude 72°03,-80°20°E longitude, with an average annual rainfall of 60-80cm. The state exhibits varied climatic and topographic conditions and provide a congenial environment for the luxurious growth of diverse groups of plants and fungi. However, information regarding the macro-fungal inventorization from this state is limited. In this backdrop, a systematic study of mushroom diversity from Western Kashmir Himalaya was undertaken. During the course of field survey from March 2009 to December 2010, two new species Mutinus caninus (Huds.) Fr. and Gyromitra sphaerospora (Peck) Sacc. were reported from the surveyed area. These species were identified on the basis of macro and microscopic characteristics and are first records from Kashmir Himalaya.
