Enzymatic biodiesel production from palm oil and palm kernel oil using free lipase

AbstractBiodiesel from biological materials is receiving attention as alternative fuel. This investigation compared quality of biodiesel produced from lipase-transesterified palm oil (PO) and palm kernel oil (PKO) based on fatty acid methyl esters (FAME) and fuel properties. Biodiesel yield was optimized using three-level four-factor of Design Expert Software with enzyme load (2.5–7.5%), methanol-oil molar ratio (3-1, 1), and temperature (30–40°C) as variables. Biodiesel properties FAME, Flash Point (FC), Pour Point (PP) and kinematic viscosity were compared with American (ASTM D6751) and European (EN 14214) Standards. PO (>90%) biodiesel yield was higher than PKO (<90%), both with maximum yields observed at 40°C, 3:1 and 5–7.5%. FAME in PO-biodiesel (POBD) and PKO-biodiesel (PKOBD) include Hexadecanate and 9-Octadecenoate, while POBD had more unsaturated FAME (Dodecanoate). POBD and PKOBD had PP 6.7°C and 17.7°C respectively, while POBD Kinematic viscosity (813kg/m3) agreed with both standards. This study showed that POBD could be a better fuel alternative with further improvement of fuel properties

Optimization of biodiesel production from spent cooking oil by fungal lipase using response surface methodology

This study evaluated the potential of optimizing Spent Cooking Oil (SCO) transesterification for biodiesel production using Response Surface Methodology (RSM). Potential biodiesel yield from transesterification was optimized using a three-level four factor Response Surface Central Composite Design (RSCCD) with methanol oil ratio (1:1 to 3:1), temperature range 35-45 °C, agitation speed range 100-200 rpm and enzyme load 10-20%. Biodiesel properties including fatty acid methyl ester (FAME), Flash Point (FP), Pour Point (PP) and kinematic viscosity were compared with American (ASTM D6751) and European Union (EN 14214) standards. Biodiesel production was optimum at 3:1 methanol to oil ratio, temperature of 35 °C, agitation speed of 150 rpm and 20% enzyme load. 9 octadecanoic acid-hydroxyl methyl ester (33.83%) was the prominent FAME produced, while the viscosity (6 mm2/s), density (893 kg/m3), FP (260 °C) and PP (-0.5 °C) all met both American and European standards. This study showed that RSM is a viable methodology which could be used for optimization of biodiesel production from biological sources.Keywords: Biodiesel; Spent cooking oil; FAME; Response Surface Methodology (RSM); Central Composite Desig

Breed differences in growth parameters of broiler chickens

Broilers been essentially a meat type of chicken, coupled with its fast growth rate has been evaluated for factors that may affect its growth, which include but not limited to sex, breed and feeding. This study was carried out to evaluate breed differences in growth parameters of four different broiler breeds. The experimental units were derived from four commercial broiler breeds namely Arbor Acre®, Cobb®, Marshall® and Ross®. Each breed had 76 chicks totaling 304 across the four breeds. On arrival, each chick was tagged using a coloured leg tag, by breed and identification number, and the initial weight of the chicks were taken. Each of the breeds were thereafter randomly selected and assigned to four experimental plots as replicates of the same treatment, ensuring that each replicate had exact number of birds per breed. The broiler birds were reared for a period of 10 weeks and their weight taken and recorded at weekly intervals. All statistical analyses were conducted using boxplot, descriptive and general linear models of Minitab® 17. At the end of the experiment and after exploratory analysis to check for normality and outliers, a total of 217 birds were used in the final analyses. Except for the Marshall breed that had a highly significantly (P&lt;0.01) lower initial weight, final weight, total weight gain and average daily gain, the other three breeds had fairly similar weight. However, there was no significant (P&gt;0.05) difference in mean initial weight across the four replicates. While breed alone accounted for 37.81% of the total variation in initial weight, it only accounted for 30.31%, 30.07% and 30.07% respectively for final weight, total weight gain and average daily gain. The effect of breed on initial weight, total weight gain and average daily gain was only significant (P&lt;0.01) in Marshall, while the other three breeds were not statistically different (P&gt;0.05). It can be deduced from this study that performance in terms of growth parameters for most of the commercially available breeds studied are similar with the exception of Marshall breed which had significantly (P&lt;0.05) lowest values

Strain improvement of Aspergillus flavus for enhanced ascorbic acid production by physical and chemical mutagenesis

The demand for ascorbic acid in the food and pharmaceutical industry led to the search for hyper ascorbic acid producing strains by physical and chemical mutagenesis. Spores of Aspergillus flavus were subjected to Ultraviolet (UV) radiation (240 nm) and Ethidium Bromide (EB) (25, 50, 75 and 100 μg/ml) to develop hyper-producing mutants. The selected mutants were cultured in a liquid fermentation medium containing Brewery Spent Grain (0.6 % w/v) at pH range 4 - 8, temperature range 30 - 45 °C, agitation speed range 60 - 160 rpm for 96 h. Ascorbic acid produced was quantified by titration techniques and with High Performance Liquid Chromatography (HPLC). The UV and EB mutant strains of A. flavus gave increased ascorbic acid yields of 6.99 g/L and 7.28 g/L respectively when compared to the parental strain with ascorbic acid yield of 3.92 g/L. Optimum ascorbic acid yields were produced at 40 °C, pH 5.0 and 100 rpm at 96 h of fermentation. This study shows the potential of strain improvement for enhanced ascorbic acid production.Keywords: Ascorbic acid; Ethidium bromide; Ultraviolet radiation; Aspergillus flavus; Mutagenesi

Purification and Characterization of Lipase from Aspergillus flavus PW2961 using Magnetic Nanoparticles.

Lipase from Aspergillus flavus was purified in a single step purification using MnFeO4 magnetic nano particles to achieve a 20.53- fold purification with specific activity of 11.29 U/mg and a 59% recovery yield. SDS-PAGE of lipase showed a single pure band with corresponding molecular weight of 35 kDa. The optimal temperature and pH for the enzyme activity were 45°C and 7.0 respectively. Addition of olive oil (1 %w/v) enhanced pH stability of the lipase with 86% residual activity at pH 7.0 after 6 h of incubation while the lipase was thermostable with 79% residual activity after 4 h of incubation. The enzyme activity was enhanced by Ca2+, Mg2+ and Mn2+ while the presence of Cu2+, Co2+ and Zn2+ exhibited inhibitory effect on the enzyme. The study therefore presented lipase from Aspergillus flavus PW2961 with potential in industrial and biotechnological application.Key words: Lipase, purification, Aspergillus flavus PW2961, magnetic nanoparticle

Performance Assessment of some Phishing predictive models based on Minimal Feature corpus

Phishing is currently one of the severest cybersecurity challenges facing the emerging online community. With damages running into millions of dollars in financial and brand losses, the sad tale of phishing activities continues unabated. This led to an arms race between the con artists and online security community which demand a constant investigation to win the cyberwar. In this paper, a new approach to phishing is investigated based on the concept of minimal feature set on some selected remarkable machine learning algorithms. The goal of this is to select and determine the most efficient machine learning methodology without undue high computational requirement usually occasioned by non-minimal feature corpus. Using the frequency analysis approach, a 13-dimensional feature set consisting of 85% URL-based feature category and 15% non-URL-based feature category was generated. This is because the URL-based features are observed to be more regularly exploited by phishers in most zero-day attacks. The proposed minimal feature set is then trained on a number of classifiers consisting of Random Tree, Decision Tree, Artificial Neural Network, Support Vector Machine and Naïve Bayes. Using 10 fold-cross validation, the approach was experimented and evaluated with a dataset consisting of 10000 phishing instances. The results indicate that Random Tree outperforms other classifiers with significant accuracy of 96.1% and a Receiver’s Operating Curve (ROC) value of 98.7%. Thus, the approach provides the performance metrics of various state of art machine learning approaches popular with phishing detection which can stimulate further deeper research work in the evaluation of other ML techniques with the minimal feature set approach

Clarification of orange juice by crude fungal pectinase from citrus peel

Fungal pectinase enzyme was produced by Rhizopusoryzae on a solid culture containing citrus peel of orange (35% w/v). The crude extract with maximum pectinase activity of 1, 360 u/ml was used to clarify orange juice. The yield, turbidity and viscosity as well as pH, total soluble solids, ascorbic acids and total titratable acidity of the clarified juice were determined. The optimum yield (97%) of juice was obtained at 1% pectinase enzyme concentration, while the turbidity and viscosity decreases with increasing concentration of pectinase enzyme. There were no marked changesin thepHandtotaltitratableacidityofthepectinase enzyme treated juice. Ascorbic acid and total soluble solids increase with increasing pectinase enzyme concentration.Thereweresignificantdifferences(p<0.05) in the pectinase enzyme concentrations on the yield, viscosity, turbidity and total titratable acid of the orange juice while no significant (P>0.05) difference was found in the pH, ascorbic acid and total soluble solids. The results presented citrus peel as substrate for pectinase production and its subsequent use in the clarification of orange juice could enhance fruit juice processing in the tropics

Second law analysis for hydromagnetic couple stress fluid flow through a porous channel

In this work, the combined effects of magnetic field and ohmic heating on the entropy generation rate in the flow of couple stress fluid through a porous channel are investigated. The equations governing the fluid flow are formulated, non-dimensionalised and solved using a rapidly convergent semi-analytical Adomian decomposition method (ADM). The result of the computation shows a significant dependence of fluid’s thermophysical parameters on Joule’s dissipation as well as decline in the rate of change of fluid momentum due to the interplay between Lorentz and viscous forces. Moreover, the rate of entropy generation in the flow system drops as the magnitude of the magnetic field increases

Clarification of orange juice by crude fungal pectinase from citrus peel

Fungal pectinase enzyme was produced by Rhizopusoryzae on a solid culture containing citrus peel of orange (35% w/v). The crude extract with maximum pectinase activity of 1, 360 u/ml was used to clarify orange juice. The yield, turbidity and viscosity as well as pH, total soluble solids, ascorbic acids and total titratable acidity of the clarified juice were determined. The optimum yield (97%) of juice was obtained at 1% pectinase enzyme concentration, while the turbidity and viscosity decreases with increasing concentration of pectinase enzyme. There were no marked changesin thepHandtotaltitratableacidityofthepectinase enzyme treated juice. Ascorbic acid and total soluble solids increase with increasing pectinase enzyme concentration.Thereweresignificantdifferences(p<0.05) in the pectinase enzyme concentrations on the yield, viscosity, turbidity and total titratable acid of the orange juice while no significant (P>0.05) difference was found in the pH, ascorbic acid and total soluble solids. The results presented citrus peel as substrate for pectinase production and its subsequent use in the clarification of orange juice could enhance fruit juice processing in the tropics