Aim: The aim of the study was to investigate crude oil degradation using first and second order kinetic models, microbial activity using dehydrogenase assay.
Place and duration of Study: Department of soil science, University of Nigeria Nsukka, Enugu State from October 2015 to March 2016.
Methodology: Characterisation and microbial analysis of Goat manure and crude oil contaminated soil were investigated. Dehydrogenase assay was used as a measure of microbial activity microbial count using Heterotrophic plate count was also investigated. Experimental data were fitted into both first and second order kinetic models and biological half-lives in order to evaluate the kinetic parameters and half-lives.
Results: The physiochemical characterisation showed that Goat manure contained valuable sources of soil nutrient and organic matter, which enhanced the bioremediation process. The result obtained from the physiochemical characterisation of the control sample showed the inadequacies of soil nutrient in the crude oil contaminated soil. The microbial activity (DHA) indicated an increase in microbial activity in both the untreated crude oil contaminated soil and the Goat manure treated contaminated soil due to the presence of crude oil in the soil. Microbial count using heterotrophic plate count indicated that higher colonies were recorded in Goat manure. 70% degradation of crude oil was achieved on the 14th day of treatment, whereas only 21% was achieved in the control sample. The kinetic parameters obtained indicated that the first order kinetic model and biological half-life gave a better result (higher degradation rate and lower biological half-life) than the second-order kinetic model.
Conclusion: In this study, we have shown that the bioremediation of COCS using GM as organic nutrient enhanced CO degradation. However, an increase in microbial count and dehydrogenase assay was observed in the GM treated COCS. The obtained kinetic parameter suggests that the first order kinetic model gave a better result (high degradation rate constant and lower biological half-life) for the studied CO degradation.
The Greater wax moth Galleria mellonella belongs to the family of Pyralidae which cause great damage to the honey bee yield worldwide, a major insect model. The honey bee cultivation places are most habitat of this insect. Most the organisms of insects rely on their olfactory system to detect and analyse the sensible nature in the environment and it is mostly useful in the concept of behavioural emotions includes mating, host defence and other sensory related molecular functions. This organism is the only member of the genus Galleria and also it is found in most the places in the world. The larvae of Galleria mellonella is used as commercial product as proving the food for predatory insects. The pathogenicity and toxicology testing were making the researchers easy by replacing the use of small mammals for in-vivo and in-vitro studies. The neurological mechanism of this insect is still unclear.
The ecdysone induced protein is unique protein with various functions, types, diversity in different organisms. From the previous study indicate that the ecdysteroid regulated gene - E74 & mushroom like large body specific protein expressed in kenyon cells of brain and was involved in olfactory, neurological behaviour of insects, embryonic and larval development. The gene expression pattern was predicted by using real time PCR. From the analyzed results, that the genes MBLK & E74 genes were expressed in Galleria mellonella which allow us to better understand of neurological disorders by using this organism as a conventional animal model.
Samples for isolation were taken from natural spoiled salted foods. All acidophilic isolates were subjected under comparison for finding the most potent glutaminase producing one. Optimization of the produced enzyme was done in the light of seven environmental and five nutritional factors including incubation time, temperature, pH, buffer system, static and different shaking speeds conditions, dark and light conditions, different inoculum size, additional carbon sources, additional nitrogen sources, heavy metals, vitamins, amino acids. Five fungal isolates have been selected and were tested for their ability to grow on L- glutamine containing medium at pH 3 and 2. Only 5 fungal isolates (F1.a, F2.a, F3.a, F4.a and F5.a) were able to grow efficiently on pH3, two of them were able to grow also on pH2. The activity of enzyme was measured extracellularly and intracellularly for each isolate and were 20.34, (2.68), 17.8, (0.423), 5.77, (5.77), 10.27, (1.39), 2.28 and (0.071) U/mL respectively. The highest enzyme activity producing isolate (F1.a) was selected and identified genetically. It was found to be closely related to Aspergillus niger strain CPGM 1439 with 93% homology and accession number DQ196192.1. The yield was quiet high after optimization reached 49.59 U/mL extracellularly which is essential advantage for such production method. The maximum yield was obtained at 35°C, pH1.8, 100 ppm Mn+2, addition of iso- leucine 3.59% for 7 days incubation in dark condition and shaking speed 100 rpm. Glutaminase enzyme was produced efficiently by the finally selected acidophilic Aspergillus niger isolate and optimization lead to higher enzyme activity which was measured by U/mL in each step.
Aims: The quality of indoor air in some government health institutions in Port Harcourt was evaluated with a view to determining the level of microbial contamination and to carry out molecular identification of the microorganism in the indoor air.
Study Design: Experimental analysis of the Indoor air of frequently used wards.
Place and Duration of Study: Model Primary Health Care in Port Harcourt, Rivers State, Nigeria, between January 2018 and March 2018.
Methodology: The open plate, impingement technique was used in this study. In this technique, nutrient agar, and mannitol salt agar plates were exposed to the ambient air of the sites studied in duplicates for 15 minutes so as to enumerate and identify the heterotrophic bacteria and staphylococcal species.
Results: The mean heterotrophic bacteria and staphylococcal loads for the morning period of the Health centre ranged from 1.8×103 to 4.1×103 and 8.6×102 to 2.5×103 Cfu/m3, respectively, while the mean heterotrophic bacteria and staphylococcal load for the evening session ranged from 3.5×103 to 5.1×103 and 8.9×102 to 1.7×103 Cfu/m3, respectively. Bacillus cereus, Chryseobacterium sp, Proteus mirabilis, Staphylococcus aureus, and Staphylococcus epidermidis were the bacteria isolated.
Conclusion: The bacterial isolates in this study could contaminate hospital equipment and could cause nosocomial infections if not properly managed. Also, the bacterial loads were very high and exceeds suggested limit for air microflora.
Globally wheat is most important crop and mostly grows in rainfed areas. In cereal crops, wheat having highest protein content. In the abiotic stresses, mostly drought effects wheat productivity and at growth stages. According to climate change, frequency of drought increases in arid and semi-arid region because of water shortage. Drought effects all growth stages of wheat and more critical at flowering and grain filling stage. Losses of wheat productivity depend on the severity and duration of drought because of reducing in photosynthesis, stomata closure, metabolic activity decrease, oxidative stress increase and result in poor grain formation ultimately yield loss. Easy method to get yield from drought areas are to develop drought tolerance genotypes according to marks. Heritable variation required for the improvement, but heritability is low because of the genotypic and environmental interaction. Different genotypes of wheat behave different in drought. A comprehensive study helps us understanding of some important markers. Breeders can select well adaptive drought genotypes on the base of morphological markers (avoid leaf senescence, flag leaf, root system, grain development, stay green character, cuticular wax and stomata conductance.), physiological markers (abscisic acid (ABA), proline, chlorophyll content, jasmonic acid (JA) and cell stability) and molecular markers (Dreb 1, Dreb 2, Rht 8, TaMYB33, TaRZF38 etc.). Several genes which are doing job for drought stress tolerance and change the enzymes and proteins like, late embryogenesis abundant, rubisco, responsive to abscisic acid, glutathione-S-transferase, carbohydrates, helicase, and proline during drought stress. Drought stress alters some gene expression and cannot work properly due to the influence of environmental factors. Researchers used biotechnological tools to identify the specific genes for drought tolerances. These markers help us to identified drought tolerance genotypes for breeding program. This review paper covers morphological, physiological and molecular marks for the development of drought tolerance genotypes.