A mathematical model was proposed to appropriately describe the fate of multicomponent substrates in porous media, especially soil. The model utilized appropriate biodegradation kinetic expressions that better describe the consumption or degradation rate of the substrate. The Equation, with the second and third type boundary conditions in non-dimensionalized form, was solved using the Finite Volume method and simulated in the Matlab environment. An experiment, using a 5 cm (inside diameter) x 60 cm (height) glass column packed with severally autoclaved soil spiked with 2 % substrate (a mixture of hexadecane, heneicosane, 1-methylnaphthalene, 2-methylnaphthalene, and 1, 3-dimethylnapthalene) and a consortium of organisms (Providential rettgeri, Streptococcus salivarius, Trichoderma harzianum, Aspergillus flavipes, and Candida famata) was set up to validate the model. The result showed that the model describes the fate of each component within the multicomponent substrate. It also indicates that both Peclet and Thiele numbers affect the biodegradation of the substrate. It was observed that a small Peclet number should be allowed for effective biodegradation of the substrate. The model was validated with data obtained for an experiment where a mixture of hydrocarbons was degraded with a mixed culture of microorganisms. The results of the experiment were well described by the model indicating that the model can be used to predict the compositions of components of a mixture during biodegradation.

Cassava starch and expanded polystyrene [EP] (Styrofoam) were collected and converted into adhesives.Two starch-based glue were produced from the hydrolysis and dexrination of cassava starch, while the expanded polystyrene was formulated through the dissolution of the solid in benzene.The produced adhesives were tested based on their bonding capacity using four substances: thermoplastic cup, plywood, garden hose and papers.The Expanded polystyrene glue could form bonds with all four materials.The tack/drying time was also recorded during the bonding moments.The rheological properties of the formulated adhesives were studied and it was seen that the glues produced showed properties of a shear-thinning/ pseudo-plastic fluid.

The biodegradation of a mixture of aliphatic and polyaromatic hydrocarbons as multicomponent substrates in a liquid medium by pure and mixed cultures of two bacteria, Providential rettgeri and Streptococcus salivarius, two moulds, Trichoderma harzianum and Aspergillus flavipes, and one yeast, Candida famata, was investigated in this study. The microbes were isolated from petroleum hydrocarbon contaminated soil in the Niger Delta, Nigeria. The fate of the various components in the substrate was monitored individually, and each component was found to decrease during the degradation period. The degrading ability of the consortium was further studied by quantifying the growth of the culture using cumulative Carbon (vi) oxide produced and the optical density method. The rate of degradation of each hydrocarbon was monitored, and growth was observed correspondingly to the degradation of the substrates. At the end of 5 days, 86.54%, 81.85%, and 81.71% of 2-methylnaphthalene, 1-methylnaphthalene, and 1,3-dimethylnaphthalene, respectively, were degraded, while 59.65% and 73.61% of hexadecane and heneicosane, respectively, were degraded. Further degradation was obtained after 11 days, resulting in 2.36%, 3.30%, 5.90%, 6.13%, and 6.35% degradation of 2-methylnaphthalene, 1-methylnaphthalene, 1,3-dimethylnaphthalene, hexadecane, and heneicosane, respectively. Kinetic parameters such as the maximum substrate consumption rates of 0.507, 0.194, 0.798, 1.490, and 0.731 g/g/hr, and the affinities of 20.70, 6.31, 50.60, 601.0, and 358.0, were obtained for 2-methylnaphthalene, 1-methylnaphthalene, 1,3-dimethylnaphthalene, hexadecane, and heneicosane, respectively. This result showed the prospect of the defined consortium for bioremediation of multicomponent substrates.

The possibility of microbial degradation of plastic waste was investigated by isolating microorganisms present in dumpsite containing low-density polyethylene (LDP). Aspergillus niger (fungi) and Pseudomonas sp. (bacteria) were identified and subsequently used to biodegrade plastic waste. The medium was made up of 0.2 g of MgSO4, 1.0 g of KH2PO4, 1.0 g of K2HPO4, 1.0 g of NH4NO3, 0.02 g of CaCl2, 0.05 g of FeCl3 in 1000 ml water. 10 ml of the medium containing the bacteria and/or fungi was poured into test tubes and 0.1 g of the plastic sample (Pure water sachet) pre-treated with ethanol was introduced into the tubes. The pH of the medium was adjusted to 7.2, 5.4 and 6.0 for Pseudomonas sp., Aspergillus niger and the mixed culture respectively. Each experiment was carried out aerobically at room temperature and incubated on a rotary shaker at 120 rpm. The weight loss in each experiment was monitored at 10 days interval for 60 days. The total weight loss after 60 days was 7.2%, 12.4%, 15% for degradation with Pseudomonas sp., Aspergillus niger and the mixed culture respectively. From this study it can be inferred that Pseudomonas sp. and Aspergillus niger have the ability to degrade plastics. It can also be inferred that Aspergillus niger degraded plastics better than Pseudomonas sp. and there was synergy between the two microorganisms since the mixed culture gave a higher degradation.

The biodegradation of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene, 2-methylnaphthalene and anthracene was investigated using pure and mixed culture of Paenbacillus alvei (bacteria) and Penicillum restricum (fungi) (isolated from crude oil contaminated sites in Rivers state of Nigeria). The abilities of these organisms to biodegrade the PAHs were studied by growing the isolates in a mineral salt medium (MSM) with the PAHs in shake flasks placed in a shaking water bath rotating at 150 rpm at room temperature for 21 days. The samples were withdrawn every three days for analysis of the residual PAHs using SRI 8610C Gas Chromatograph (GC), while the growth of the organisms was determined by using the dry biomass method. The results showed that the concentrations of PAHs decreased with an increase in the exposure time throughout a 21-day period, thus confirming the abilities of the organisms to feed on the PAHs. The results showed that the bacteria had more affinity for naphthalene, while the fungi had more affinity for anthracene. It was, however, observed that the samples from the flask which contained mixed PAHs and mixed culture of Paenbacillus alvei and Penicillum restricum had the highest and most significant biomass growth thus suggesting a synergy between the two organisms.

Efficient pre-treatment has been found to be crucial step before enzymatic hydrolysis of cellulose into fuels or chemicals. As a result various pretreatment methods have been developed to facilitate these bio-conversion processes, and this research focuses on the effect of two pretreatment methods such as liquid hot water and sulphuric acid pre-treatment to remove some of the components like lignin and hemicellulose which form structural barrier to enzymatic accessibility of cellulose in corn cobs and sawdust. The cellulosic materials were first dried in oven at 65 o C for 24 hours,  and using   solid to liquid ratio of 1:10, the two methods were carried out at resident times ranging from 10 - 40 minutes. The liquid hot water method involved heating the cellulosic materials in water at 120 o C and 1atmosphere in a pressure vessel, and for the second method, the dried cellulosic materials were refluxed in 5 % sulphuric acid at a temperature of 120 o C. Pretreated samples were filtered and liquid fractions were analyzed for the presence of reducing sugars, while solid residues were dried in the oven and weighed to measure the mass lost during pretreatment as a pointer to lignin breakdown. It was observed that the mass lost increased with time for both pretreatment methods, but the liquid hot water pretreatment gave higher lignin and hemicellulose removal when compared to the sulphuric acid pre-treatment. The pretreated materials were hydrolyzed with two combinations of commercial enzymes namely cellulase/ hemicellulase and cellulase/β glucosidase. The reducing sugar was measured using Dinitrosalycilic acid (DNSA) method and the sugar yields from corn cobs were higher than that of sawdust when subjected to similar process conditions, and the enzyme combination of cellulase/glucosidase gave higher yields of reducing sugars.  A model equation which describes the hydrolysis process was developed from first principles and the experimental data obtained gave a good fit.

Efficient cellulose hydrolysis remains one of the most challenging problems in attempting to convert cellulose wastes into fuels or chemicals, and pre-treatment has been found to be crucial step before enzymatic hydrolysis of these polymers can effectively take place. As a result various pre-treatment methods have been developed to facilitate these bio-conversion processes, and this research focuses on the effect of two pre-treatment methods such as low pressure steam and sulphuric acid pre-treatment to remove some of the components like lignin and hemicellulose which form structural barrier to enzymatic accessibility of cellulose in corn cobs and sawdust. The cellulosic materials were first dried in oven at 65oC for 24 hours, and using solid to liquid ratio of 1:10, the two methods were carried out at resident times ranging from 10 - 40 minutes. The low pressure steam method involved heating the cellulosic materials in an autoclave at 120oC and 1atm above the normal atmospheric pressure; for the second method, the dried cellulosic materials were refluxed in 5 % sulphuric acid at a temperature of 120oC. Pre-treated samples were filtered and liquid fractions were analysed for the presence of reducing sugars, while solid residues were dried in the oven and weighed to measure the mass lost during pre-treatment as a pointer to lignin breakdown. It was observed that the mass lost increased with time for both pre-treatment methods, but the low pressure steam pre-treatment gave higher lignin and hemicellulose removal when compared to the sulphuric acid pre-treatment. The liquid fractions after pre-treatment were found to contain some reducing sugar which increased with pre-treatment time and was higher in the corn prehydrolysate. The pre-treated materials were hydrolysed with two combinations of commercial enzymes namely cellulase/ hemicellulase and cellulase/β glucosidase. The reducing sugar was measured using Dinitrosalycilic acid (DNSA) method and the sugar yields from corn cobs were higher than that of sawdust when subjected to similar process conditions, and the enzyme combination of cellulase/glucosidase gave higher yields of reducing sugars. A modified form of the model equation used to describe the basic hydrolysis process gave a good fit the experimental data obtained.

Starch from cassava and maize was chemically modified and compared with pharmaceutical grade starch. The starch was extracted using local methods and chemically modified with acetic anhydride in the presence of an alkaline catalyst, and also, by addition of gum arabic to improve the binding characteristics and gelatinization temperature. The desired parameters such as solubility, pH, swelling power and moisture content were measured for both chemically modified starch and found to compare favourably with the pharmaceutical grade starch. The addition of gum arabic generally improved the gelatinization temperature as well as the binding characteristics.

The microbial activities and the biodegradation-abilities of undefined consortium in contaminated soils in the Niger Delta of Nigeria were studied. The Respirametry technique was adopted to evaluate the microbial activities while the soils were incubated with 2% (υ/υ) crude oil in mineral salt medium at 37°C in three stages of two weeks each in a shake flask. At the end of the last phase, components of the crude oil degraded by the undefined consortium in the soils were identified with the gas chromatographic techniques. The consortia of the different samples studied showed different degree of capacities on the crude oil, removing a large number of components of the crude oil, making the areas potentially suitable for in-situ bioremediation.

Pseudomonas aeruginosa and Pseudomonas fluorescens are among the common bacteria found to mediate in the biodegradation of hydrocarbon, as well as in cleaning up environment contaminated with such. But little is known about their contributions, in term of their abilities in degrading diesel oil. Therefore, this study is with a view to establish and compare their bioremediating potentials on diesel oil. The pure and mixed cultures of Pseudomonas aeruginosa and Pseudomonas fluorescens were incubated in mineral salts media with diesel oil as the source of carbon and energy, at 28°C for 14 days in a Gyratory shaker at 200 rpm. Samples were withdrawn at 48-hours intervals, and centrifuged at 5000 rpm for 30 minutes. Biomass growth was measured on dry weight basis while diesel oil consumption was estimated from the supernatants after treatment with petroleum ether by spectrophotometric methods. The growth and substrate utilization parameters based on integrated balance analysis were obtained and the results obtained showed that P. aeruginosa and P. fluorescens, in both pure and mixed cultures propagated well on diesel oil. It was observed that within 5 days of incubation, 54%, 51% and 75% of the diesel was consumed by P. fluorescens, P. aeruginosa and the mixed culture, respectively. From the re-parameterized Monod Kinetic model, the Monod constant values obtained were 10.25, 22.84 and 2.64 gl-1 for P. aeruginosa, P. fluorescens and the mixed culture, respectively. The maximum specific substrate consumption rates of 1.008, 1.066 and 0.668 gg-1.day-1 were obtained for P. aeruginosa, P. fluorescens and their mixed culture, respectively. These results showed that with relatively higher percentage of degradation and lower maximum specific substrate consumption rate the P. aeruginosa and the mixed culture gave better degradation than the P. fluorescens.

The dominant microorganisms present in soils, contaminated with hydrocarbon fractions in engine oils (used and unused) at various automobile workshops in five locations in the city of Lagos were isolated. The purpose of the work was to evaluate the effectiveness of the several microorganisms indigenous to the soil in remediating the soil. Bacillus species and Pseudomonas species were found in all the sites, while flavobacterium and micrococcus species were found in three of the sites and only one the site had the rhodococcus species. The effectiveness and efficiencies of degradation of the hydrocarbon components by the isolated organisms were studied in shake flaks containing minimal salt medium with varying concentrations of engine oil (0.5%, 1.0%, and 1.5%). Each isolated organism and mixtures of them were grown in the various media in an incubator shaker at room temperature. The extent of growth of organisms observed was linked to the ability of the organisms to biodegrade the hydrocarbon fractions present in the medium. The results obtained showed that the pseudomonas and rhodococcusspecies gave the best growth at all concentrations of engine oil used, degrading 60% and 80% of oil respectively. A co-culture of these two organisms gave a higher growth than each of them when cultured alone, suggesting a positive interaction between the two organisms. This could be attributed to their ability to degrade different types of hydrocarbons thus creating the synergy. It can be concluded that an efficient bioremediation programme can be put in place by the use of an appropriate mixture of organisms as well as other physico-chemical properties that might also influence the growth of these microorganisms.