Antimicrobial activities of secondary metabolites of endophytic fungi isolated from Catharanthus roseus

Introduction: Recently, several endophytes have been shown to possess the potentials to synthesize novel bioactive compounds that have found use for drug discovery. We isolated endophytic fungi associated with Catharanthus roseus collected from the river banks of Amassoma in Southern Nigeria, and identified some of their bioactive secondary metabolites. Methods: The fungi were subjected to solid-state fermentation on rice medium and the metabolites were extracted using ethyl acetate. The fungal crude extracts were screened for antimicrobial activity and were also subjected to high-performance liquid chromatography-diode-array detection (HPLC-DAD) analysis for the identification of the bioactive compounds. Results: The fungal extracts showed both antibacterial and antifungal activities with minimum inhibitory concentrations ranging from 0.0625 to 1 mg/mL. The HPLC-DAD analysis of the extracts suggested the presence of citreoisocoumarin, citreoisocoumarinol, questinol, hydroxyemodin, acropyrone, methyl 2-(4-hydroxyphenyl) acetate, nigricinol, and cladosporin. Conclusion: The results of this study suggest that endophytic fungi associated with C. roseus could be a promising source of novel bioactive compounds with pharmaceutical and industrial importance

Quality Assurance Mechanisms as Means for Improving Certification of Output in Universities in Niger Delta States

Proliferation of university education and global labour impacts on Nigeria economy has continued to increase the demand for quality assurance. As a result, concerted efforts are required by universities to internalize the culture of quality in their production function in order to produce employable graduates that can drive the needed change and build sustainable economy.  Hence, the paper attempted to investigate internal quality assurance mechanisms adopted by universities in Niger Delta as a means for improving the overall quality of certification of output. The sample of 105 academic heads consists of Deans; Heads of department and Directors were sampled in three (3) universities in Niger Delta geo political zone.  A 20-item instrument titled ‘’ Quality Assurance Mechanisms and Certification of Output Questionnaire’’ (QAMCOQ) was designed in five Likert measuring scale and analyzed with descriptive statistics.  The results however have shown that the certification processes of graduates across universities in Niger Delta State can be strengthened by the internal quality assurance. Some quality assurance indicators identified include clearly defined goals of academic programme, involvement of academics in entrenching the culture of quality, strengthening admission procedure through the post university matriculation examination, preparation and submission of question paper, answer model and marking scheme, submission of examination booklets, and adherence to carrying capacity by management of universities and infrastructural improvement in the affected universities. It was therefore recommended that proprietors and managers of universities and relevant regulatory commission should continue to strengthen the processes of certification and provide more infrastructures to support the attainment of the National goals of university education. Keywords: Quality, Quality Assurance, Quality Assurance Mechanism

An Analysis of the Influence of Informal Grouping Dynamics on Organizational Performance in the Nigerian Telecommunication Sector

There is exponential growth in number of studies focused on performance of firms considering the increased level of competitiveness. Much of the studies so far had shown concern for factors within the environment of organization and how they link performance. This notwithstanding, this study is focused on behavioural dynamics of informal grouping and its link with performance in the telecommunication subsector of the Nigerian economy. The survey instrument was used in generating data from a sample of 112 sample subjects. From the inferential analysis, a strong positive and significant relationship exists between informal group dynamics and performance. Value reinforcement behavior dimension has more weight with ρ = 0.412 amongst other dimensions of informal group dynamics. It was concluded that informal groups are social network within work organizations that ultimately serve as a strategic means of enhancing performance through innovativeness and responsiveness. It was therefore recommended that informal groups should subsist at work in as much as their existence is regulated by organizational policies

WORKING CAPITAL MANAGEMENT AND FIRMS’ FINANCIAL PERFORMANCE: EVIDENCE FROM LISTED NIGERIAN FIRMS

This study investigated the influence of Working Capital Management (WCM) on the financial performance of publicly listed companies in Nigeria. The analysis of secondary data from the period of 2012 to 2021 employed the utilization of cash conversion cycle, Account Receivable Management, and Account Payable Management metrics. The findings of the study indicate that there is statistically significant relationship between the cash conversion cycle and financial performance. The management of cash conversion cycle, accounts receivable and accounts payable showed a statistically significant impact on the financial performance of publicly traded companies in Nigeria. The study therefore suggests that firms should maintain an optimal level of working capital in order to maximize their overall value. Additionally, the effective management of cash flow is deemed to be of utmost importance for organizations while maintaining a balanced working capital management, with particular focus on managing account receivables, payables, and inventory. This is because efficient working capital management is anticipated to have a beneficial influence on the market value of firm

A study of modified mesoporous silica for the adsorption of selected organic pollutants.

Doctor of Philosophy in Chemistry and Physics. University of KwaZulu-Natal, Durban, 2016.Water is an essential natural resource the world over. Only one-tenth of the world’s water is pol-lution free and hence there is a need for remediating polluted water. These pollutants, some of which are organic (dyes and pharmaceuticals), are often difficult to remediate from wastewater. Of all the available remediation techniques, adsorption is a proven technique that combines ease of use and cost effectiveness in removal of these organic pollutants. This study is aimed at the synthesis and characterisation of mesoporous silica/ordered mesoporous silica from agrowastes and commercial precursors, and their utilization in adsorption of organic pollutants. Silica was modified with citric acid, graphene oxide and graphene because of silica’s ready availability, low cost and its environmentally benign nature. The synthesized materials were charactersied by means of various standard analytical techniques. In the first study, silica nanoparticles (SNP) and silica nanotubes (SNT) were synthesized from elephant grass. Parameters such as surfactant con-centration and temperature were investigated on the morphology of mesoporous silica which yielded SNTs and SNPs. These parameters, especially the surfactant concentration had a pro-found effect on the morphology of silica. SNT and SNP were applied in the adsorption of 2 dyes; methylene blue (MB) and methylene red (MR). The adsorption of MB and MR on SNT were 109.97 mg/g and 40.6 mg/g, respectively. For SNP, MB and MR adsorption was 104.85 mg/g and 40.98 mg/g, respectively. The adsorption of MB and MR increased with an increase in pH with pH 6 and 8 being the optimal pH for MR and MB, respectively. This slight difference in sorption capacities can be attributed to the surface area. Pseudo-second order and the Langmuir isotherm model best fitted the data obtained. In the second study, mobil catalytic material (MCM-41) was synthesised using tetraethylorthosilicate and elephant grass as precursors. Citric acid was used a modifier and applied in the adsorption of methylene blue. The citric acid had a significant effect on the adsorption capacity, which increased at basic pH. The mechanism for adsorption was electrostatic ion interaction. The maximum adsorption capacity of the modified material improved considerably with a qm of 204.08 mg/g at pH 10 and a temperature of 25 °C. The adsorption kinetics favoured the pseudo-second-order model and the best fit model for the equilibrium data was the Freundlich model. In the third study, MCM-41 was synthesized from millet straw (agrowaste). A citric acid-MCM-41 (SCA-MCM-41) composite was prepared by grafting citric acid (CA) onto MCM-41 for improvement of its adsorptive capacity for methylene blue (MB). The highest adsorption capacity was achieved at pH 8. The Temkin isotherm model was the best fit in analyzing the equilibrium data. Kinetics favoured the pseudo-second order and the optimum temperature for adsorption was 25 oC. In the fourth study, SNT was synthesized using elephant grass as a precursor and was encapsulated with graphene oxide and graphene and applied in the remediation of sulfamethoxazole from aqueous media. The highly hydrophobic materials had high adsorptive capacities for sulfamethoxazole. In this study, ordered mesoporous silica-graphene oxide (MCM-41-GO) and graphene (MCM-41-G) composites and as-synthesised MCM-41 were synthesized and applied in the adsorption of acetaminophen and aspirin from aqueous solution. Elemental analysis showed that the percentage carbon was MCM-41-G > MCM-41-GO > AS-MCM-41 > MCM-41. This conferred various degrees of hydrophobicity on these materials and hydrophobic interaction was the main mechanism of adsorption. The pseudo-second order model best fitted the adsorption kinetics and the Freundlich isotherm best described the equilibrium. These materials had higher sorption capacities as compared to unmodified MCM-41. In the last study, MCM-48 encapsulated with graphene and graphene oxide, and as-synthesised MCM-48 were synthesized and applied in the remediation of caffeine and phenacetin from wastewater. The results obtained were similar to that of the previous study and hydrophobic interaction was the main mechanism of adsorption. Overall the modification of mesopo-rous/ordered mesoporous materials proved very useful in the remediation of organic pollutants from aqueous media

School Climate and Students’ Academic Achievement in Public Secondary Schools in Anambra State

This study investigated school climate and students’ academic achievement in public secondary schools in Anambra State. Three research questions and hypotheses guided the study. This is a correlational survey of the ex-post-facto research design. 127(50%) respondents were sampled from a population of 254 principals using a simple sampling technique. A self-developed questionnaire titled School Climate Questionnaire was employed to collect information from respondents. While a checklist was used to obtain information on students’ academic achievement. The questionnaire was validated through the face and content validity. It was also subjected to a reliability test using Cronbach-Alpha and a coefficient of .79 was obtained revealing a high-reliability index. Coefficient of determination, Pearson r, and Regression were used for data analysis. The finding shows that the relationship between teachers’ motivation, instructional supervision, school climate, and students’ academic achievement in Anambra State was significant. It was thus, recommended that since educational supervision enhances instructors’ professional competence and the effectiveness of their instructional activities school principals should ensure that the climate of the school enhances the teacher’s job

Haematological and hepatho-renal effect of cashew nut oil on male Wistar rats

The aim of this study was to evaluate the biosafety of Anacardium occidentale (cashew) nut oil using male Wistar rats as model. Cashew nut oil was extracted from cashew nuts with the aid of a Soxhlet apparatus using n-hexane as solvent. Twelve male Wistar rats were randomly assigned to four groups labeled I, II, III and IV (3 rats per group). Group I served as the control group and were administered distilled water. Group II received 1.53 mL/kg of the nut oil; group III received 4 mL/kg of the nut oil while group IV received 8.13 mL/kg of the nut oil. The administrations were via the oral route. Blood samples were collected weekly for haematological examination. At the end of four weeks study period, the rats were anaesthetized and the liver and kidneys were removed for histological examination. The haematological result showed slight deviation from the normal in packed cell volume (52%), total white blood cell count (9.38 x 103/mm3) and lymphocyte count (58.17%) in Wistar rats administered 4 to 8.13 mL/kg of the cashew nut oil, respectively yet no visible compromise of the immune system was observed. Histological analysis; however, revealed some hepatocyte morphological lesions including mild microvesicular steatosis, kupffer cell hyperplasia, shrinkage of glomeruli, glomerular distortion, necrotic renal tubules, severe congestion and atrophy of renal tubules in rats fed 8.13mL/kg of the nut oil. In conclusion, the cashew nut oil was responsible for hepatic parenchymal and matrix alteration in wistar rats administered 8.13 mL/kg of cashew nut oil

Antimicrobial activities of secondary metabolites of endophytic fungi isolated from Catharanthus roseus

Introduction: Recently, several endophytes have been shown to possess the potentials to synthesize novel bioactive compounds that have found use for drug discovery. We isolated endophytic fungi associated with Catharanthus roseus collected from the river banks of Amassoma in Southern Nigeria, and identified some of their bioactive secondary metabolites. Methods: The fungi were subjected to solid-state fermentation on rice medium and the metabolites were extracted using ethyl acetate. The fungal crude extracts were screened for antimicrobial activity and were also subjected to high-performance liquid chromatography-diode-array detection (HPLC-DAD) analysis for the identification of the bioactive compounds. Results: The fungal extracts showed both antibacterial and antifungal activities with minimum inhibitory concentrations ranging from 0.0625 to 1 mg/mL. The HPLC-DAD analysis of the extracts suggested the presence of citreoisocoumarin, citreoisocoumarinol, questinol, hydroxyemodin, acropyrone, methyl 2-(4-hydroxyphenyl) acetate, nigricinol, and cladosporin. Conclusion: The results of this study suggest that endophytic fungi associated with C. roseus could be a promising source of novel bioactive compounds with pharmaceutical and industrial importance

Factors influencing students’ choice of a federal university: a case study of a Nigerian federal university

The factors affecting students’ choice of higher education is essential for the university’s management. Various research across the world has been carried out to understand how students select their preferred universities for tertiary study; however, there is a shortage of insight from an African perspective. Specifically focusing on a federal university in Nigeria, this study aims to explore factors influencing students’ interest in the school and why they selected it as their study location. A structured questionnaire from 282 undergraduate students based on stratified random sampling was used to understand these choice factors. The study found that personal interest greatly influenced students’ decisions, followed by parental influence, university reputation, university ranking, and fees. The results provide an understanding of students’ choices for universities in a Nigerian context, which is a loose representation of the general influences of students’ choice for study sites on the continent. This would enable stakeholders working in the Nigerian education sector including academics, administrators and practitioners and international collaborators to understand the most effective ways to reach out to prospective students and draw useful lessons for universities' marketing strategies, which could be recommended not only in Nigeria but in Africa at large

Factors influencing postgraduate students' university choice in Nigeria.

An understanding of postgraduate students’ choice criteria for universities selection is essential for marketing higher education, securing the long-term success of the universities, as well as its marketing strategy. While previous studies have focused on developed countries and undergraduate students, this chapter explores factors influencing postgraduate students’ decision making. The study recognises that the rapid expansion of the enrolment of undergraduates has also stimulated students’ enthusiasm for postgraduate studies and importantly, postgraduate students have prior experience in a university service environment (compared to undergraduate students). The semi-structured interview was conducted with first-year postgraduate students at a private university in South-West, Nigeria. Some of the participants were new to the university while some did their undergraduate studies there. Findings from the study revealed four key factors which are the desire to study for a postgraduate degree, the facilities of the University, including its geographical location, the courses on offer and influence of other stakeholders like parents, siblings and friends. This influence of stakeholders aligns with the fundamental values in a collectivist culture like Nigeria. This study contributes to literature on higher education marketing, especially in Africa and for postgraduate students. The chapter presents an integral insight into marketing higher education in Nigeria and Africa, as this is an under-researched area