Xylanase production by Aspergillus niger ANL 301 using agro - wastes

Xylanase production by wild-type Aspergillus niger ANL301, newly isolated from wood-waste, was monitored at 24 h intervals for a period 168 h in media containing different carbon sources. The carbon sources were oat-spelt xylan (Fluka) and three agro-wastes (sawdust, sugarcane pulp and wheat bran). Highest xylanase activity of 6.47 units/mL was obtained at 96 h in media containing wheat bran as sole carbon source. Maximum activity value for the media containing sugarcane pulp was 0.95 units/mL obtained also at 96 h. Sawdust and oat spelt xylan gave the peak enzyme activities of 0.65 and 0.80 units/mL respectively at 120 h. High protein yield was obtained in media containing the agro-wastes, with wheat bran giving the highest value of 1.14 mg/mL at 96 h. The maximum specific xylanase activities were 3.86, 3.37, 5.69, and 9.36 units/ mg protein for sawdust, sugarcane pulp, wheat bran and oat spelt xylan, respectively. Out of the three agro-wastes used in this study, wheat bran holds greatest promise for low cost production of the xylanase enzyme

Agro-waste: a potential fermentation substrate for Penicillium chrysogenum

Common agro-wastes found in Lagos, Nigeria (cassava shavings, corncob, sawdust, and sugarcane pulp) were compared with glucose and lactose as fermentation substrates for Penicillium chrysogenum PCL501. Cassava shavings significantly (P<0.001) produced the highest amount of mycelia weight (0.43 ± 0.02 mg/ml) than all the other substrates. This was followed by corncob with peak mycelia weight of 0.33 ± 0.02 mg/ml. Peak mycelia weight of 0.27 ± 0.01 mg/ml was equally obtained with glucose and sugarcane pulp whereas lactose gave a slightly lower peak of 0.25 ± 0.01 mg/ml. Sawdust gave the least mycelia weight of 0.13 ± 0.01 mg/ml. Total sugar content of all the culture media steadily decreased as fungal growth progressed indicating that the organism utilized carbohydrates for growth and mycelia formation. Cultures containing cassava shavings and sawdust gave high protein peaks of 0.84 ± 0.05 and 0.65 ± 0.03 mg/ml respectively. Cultures containing corncob, glucose, lactose and sugarcane pulp yielded lower protein peaks of 0.37 ± 0.02, 0.30 ± 0.02, 0.24 ± 0.02 and 0.18 ± 0.01 mg/ml respectively. The results suggest that cassava shavings, corncob and sugarcane pulp could serve as cheap fermentation substrates for the growth of the fungus. Of all the substrates investigated, cassava shavings have the best potential to serve as substrate for fermentation by Penicillium chrysogenum PCL501. © 2009 International Formulae Group. All rights reserved

3-TIER E-COMP: A NOVEL E-COMMERCE MANAGEMENT PORTAL BASED ON SECURED SDLC APPROACH

In today’s business world, there is an urgent need to develop a new approach for customer to business owner transactionssecurely. This research develops, implements, and discussed a novel 3 – Tier E-Commerce Management portal. This makesonline business very flexible and secured on the part of business owners and customers. Our proposed system seeks toreplace the conventional E-commerce models on the internet today. We argue that process logic manipulation using SecuredSoftware Development Life Cycle (SSDLCM) on Ecommerce platform is a promising scheme for studying andunderstanding script processing on the new web paradigms. In this research, we define security calculus for 3 Tier EComPwith the aim of eradicating SQL injection possibilities as well as exploiting Software as a service in a dynamic Ecommercedomain. Also, we developed a new access hierarchy for E-commerce comprising of Application layer users, designatedadministrator and super administrators in the 3 – Tier EComP. We developed a new encryption scheme based on XAMPMD5 Random Curve Cryptography (XMD5 – RCC) running on Secure Socket Layer (SSL) which protects the user andadministrators on the Ecommerce platform. The result of encryption scheme randomly generates and secures the logindetails dynamically on the server during the authentication and authorization phases. The programming was accomplishedwith PhP, and MySQL Server. The overall methodology as detailed in the body of the work could serve as good template forapplication developers and other researchers.Keywords: E-Commerce, XMD5-RCC, SSL, Platform, SSDLCM, Software, Servic

Repositioning Conceptual Understanding of Adult Education for Social Transformation in Nigeria

The conceptual understanding of Adult Education and its mission has continued to suffer much neglect in various quarters in the education sector. The debate on the status of the discipline has been accorded low esteem and relegated to the background in government circles, in the intellectual community and public perception despite the huge potentials it offers in the developmental process. This paper is an attempt at repositioning the understanding of Adult Education to restore the image of poor perception from policy makers and implementers of adult education programmes in Nigeria. The paper examined the utilitarian value of adult education needed for the transformation of the plethora of problems in the economic, social and political landscape of society. It recommended that there is need to redesign adult education curriculum to sustain its nomenclature for lifelong learning to bring about the needed recognition as a career discipline in the education system for maximum benefit in Nigeria. Key Words: Repositioning, Conceptual, Understanding, Social, Transformation, Adult Educatio

Dividend Policy and Share Price Volatility in Nigeria

The purpose of this paper is to examine the relationship between dividend policy and share price changes in the Nigerian stock market. A multiple regression analysis is used to explore the association between share price changes and both dividend yield and dividend payout ratio. Of the two measures of dividend policy, dividend yield showed a general negative impact on share price risk. The other measure of dividend policy, dividend payout ratio, showed negative influences in some years and positive influences on others though all were at lower significant levels. The study supports the fact that dividend policy is relevant in determining share price changes for a sample of firms listed in the Nigerian Stock Exchange. The challenge for managements/accountants is to generally improve the quality of the financial statements to avoid producing wrong information which could lead to wrong decisions by investors

Xylanase production by Penicillium chrysogenum (PCL501) fermented on cellulosic wastes

Xylanase production by Penicillium chrysogenum PCL501, newly isolated from wood-wastes, was monitored at 24 h intervals for a period 168 h in media containing four different carbon sources (oatspelt xylan, wheat bran, sawdust, and sugarcane pulp). The highest xylanase activity of 6.47 Units mL-1 was obtained at 96 h in media containing wheat bran whereas media containing sugarcane pulp gave a peak value of 1.39 Units mL-1 at 144 h. Sawdust and xylan gave a peak xylanase activity of 1.35 and 0.79 Units mL-1 respectively at 120 h. Maximum protein released in xylan-containing media was 0.38 mg mL-1. Higher protein yield was obtained in media containing the agro-wastes, with wheat bran giving the highest value of 1.14 mg mL-1. The maximum specific xylanase activities were 2.59, 8.52, 16.06, and 9.36 Units mg Protein -1 for sawdust, sugarcane pulp, wheat bran and xylan respectively. Out of the three agro-wastes used in this study, wheat bran holds the greatest promise for cost-effective production of the xylanase enzyme. The carbon source is the highest inducer of the enzyme in the fungus

Effect of carbon sources on cellulase (EC 3. 2. 1. 4) production by Penicillium chrysogenum PCL501

The effects of glucose, crystalline cellulose and sawdust of Mitragyna cilata on the growth and cellulase production, inferred from cellulase (EC 3. 2. 1. 4) activity, of Penicillium chrysogenum PCL501 was determined. Glucose-containing media gave the highest mycelia weight of 1.78 mg mL-1 in 120 h of incubation. This is about 3.5 – 4.5 times the maximum weights of 0.51 and 0.40 mg mL-1 respectively obtained from the cultures containing cellulose and sawdust. The cultures containing crystalline cellulose and sawdust produced extracellular protein with cellulase (EC 3. 2. 1. 4) activity whereas glucose-containing cultures yielded very low protein and no significant cellulase activity. Maximum protein content of 0.02, 0.13 and 0.46 mg mL-1 respectively were obtained from the cultures containing glucose, cellulose and sawdust. Peak cellulase activity values of 100.0 and 92.2 Units L-1 respectively were obtained for the cultures containing cellulose and sawdust. There is a correlation between the protein released and cellulase activity of the culture filtrates. P. chrysogenum PCL501 produces extracellular proteins with significant cellulase activity in media containing cellulose and sawdust but not in glucose-containing medium. Sawdust is indicated as a good inducer of cellulase activity in the organism. The waste cellulosic material can be used as low-cost carbon source for commercial cellulase production

Plant Waste Hydrolysis by Extracellular Enzymes of Aspergillus niger and Penicillium chrysogenum: Effect of Ammonia Pretreatment

Aspergillus niger (ANL301) and Penicillium chrysogenum (PCL 501) cultured in basal media with cellulose as sole carbon source yielded extracellular enzymes which partially hydrolyzed sawdust and sugarcane pulp into simple sugars. Pre-treatment of sawdust by ammonium hydroxide steeping increased the yield of simple sugars. The reducing sugars released from the pretreated sawdust by the crude enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) were 3.58% and 7.02% of the total hydrolysable sugars respectively. This is in contrast to the 0.92% and 1.02% of the total hydrolysable sugars released respectively by the enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) from the non-pretreated sawdust. Enzymatic hydrolysis of sugarcane pulp by the crude enzymes was not significantly affected by ammonia pre-treatment. Reducing sugars released from non-pretreated sugarcane pulp by the crude enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) were respectively 4.17% and 5.08% of the total hydrolysable sugars

Optimization and electrochemical study on the control of mild steel corrosion in hydrochloric acid solution with bitter kola leaf extract as inhibitor

Response surface methodology was applied to predict the optimum control of mild steel corrosion in acid medium with bitter kola leaf extract as inhibitor. The experiment was carried out to investigate the mutual interactions between the considered independent variables and the expected responses. Thermometric, gravimetric, potentiodynamics polarization and electrochemical impedance spectroscopy were used in the corrosion inhibition study. As a supplementary technique, infrared spectroscopy was used to analyze the pure extract and corrosion products and it was observed that some peaks shifted while some disappeared. Inhibition efficiencies of 88.24 %, 86.81 %, 90 %, 89.5 % and 85.3 % were obtained from optimization, thermometric, gravimetric, potentiodynamics polarization and electrochemical impedance spectroscopic techniques, respectively. The bitter kola leaf extract behaved as a mixed-mode inhibitor. Application of response surface methodology in this study was found to be good in predicting the optimum range for controlling of metal corrosion thereby reducing the number of experimental runs.Keywords: Acid, bitter kola leaf, Fourier transform infrared, mild steel, electrochemical impedance spectroscopy, potentio dynamics polarizatio

Assessment of runway excursion causal factors and mitigation strategies

Runway excursion (RE) is a significant cause of many aircraft accidents worldwide. Statistic reveals that accident associated with RE is on the increase. Although RE accident fatalities are usually lower with respect to loss of control (LOC) caused accidents, however the aircrafts involved in RE caused accidents are usually write-off. In response to the raising threat to aviation safety, the Research and Development (R&amp;D) division of the Air Force Institute of Technology (AFIT), Nigerian Air Force (NAF) Base, Kaduna Nigeria was tasked to conduct a study on RE problem. The study gathered of three kinds of secondary information associated with RE accidents: 1) statistical summaries, 2) accident report that cited runway excursion accident and 3) stakeholders inputs. Using this resources, the RE causal factors were identified. This paper described the study method, stakeholder viewpoint; key identified causal factors for RE caused accidents and mitigation strategies.Keywords: Aircraft accident, causal factor, runway excursion, mitigation strategie