36 research outputs found
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
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
Latex glove sensitivity amongst diagnostic imaging healthcare personnel: a study in Southeastern Nigeria.
The paper reports a cross-sectional study to determine the prevalence
and type of symptoms, causal agents and awareness of latex glove
reactions amongst four professional groups. The study was done at
diagnostic imaging departments within ten major hospitals in
Southeastern Nigeria. Radiologists/resident radiologists,
radiographers, radiology nurses and darkroom technicians who were
occupationally exposed to latex gloves were investigated between June
and September 2006 to determine the level of latex hypersensitivity.
The results show that prevalence is similar to that demonstrated
elsewhere with 12.4% of individuals expressing latex associated
symptoms. Symptoms included itching and redness of hands, dry cracked
skin, soreness of eyes, and upper respiratory tract complaints. There
are strong relationships between number of gloves used per day,
duration of glove use and expression of symptoms. About 62.8% (n=76) of
the respondents had previous knowledge of hypersensitivity reaction to
latex gloves prior to this investigation. The paper concludes that
latex hypersensitivity is a real problem amongst diagnostic imaging
healthcare personnel in our locality. This preliminary work, therefore,
provides the basis of a much larger controlled study in the future
Incidence of community acquired ESBL-producing bacteria among asymptomatic University students in Anambra State, Nigeria
This study was conducted to investigate the incidence of community acquired extended-spectrum β-lactamase (ESBL)-producing bacteria among asymptomatic students of Nnamdi Azikiwe University, Awka, Anambra State, South-East Nigeria. A total of 102 non-duplicate strains of Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were isolated from fecal samples (n=273) collected from the participating students. The isolates were subjected to antimicrobial susceptibility tests to determine their antimicrobial resistance profile. Their multiple antibiotic resistance (MAR) indices were also evaluated. Screening of the isolates for possible ESBL production was carried out by disk diffusion test using cefotaxime and ceftazidime disks. ESBL-production by the resistant strains was confirmed using the double-disk synergy test. Most of the isolates were found to be multi-drug resistant, as all K. pneumoniae and P. aeruginosa strains (100%), and 98.4% of the E. coli strains, had MAR indices ≥0.2. A total of 22 ESBL-producing bacterial species were confirmed, and the frequency of E. coli, K. pneumoniae and P. aeruginosa isolates among the ESBL-producing bacteria were n=20 (90.9%), n=2 (9.1%), and n=0 (0.0%) respectively. The total number of ESBL-producing bacterial strains isolated accounted for 8.1 % of the entire sample population. Although this prevalence rate may not indicate an alarming situation, it is important that the proliferation of ESBL-producing bacteria in the community be contained, since a high incidence of ESBL-producing organisms will create significant therapeutic problems in the near future. There is therefore need to develop strategies to reduce their spread in the community especially through monitoring, surveillance and proper detection protocol.
DOI: http://dx.doi.org/10.5281/zenodo.131471
Biologically active phenolic acids produced by Aspergillus sp., an endophyte of Moringa oleifera
This study investigates the secondary metabolites of an endophytic Aspergillus sp. isolated from leaves of M. oleifera growing in Anambra State, South-Eastern Nigeria. Antimicrobial and antioxidant screening of the fungal extract and isolated compounds, as well as cytotoxicity assay of the extract against cisplatin-sensitive A2780 (sens) and cisplatin-resistant A2780 (cisR) ovarian cancer cell lines were carried out using standard methods. Chemical investigations of the fungal extract involving a combination of different chromato-graphic methods and spectroscopic techniques were carried out to isolate and characterize the constituents of the extract. At a concentration range of 1-4 mg/ml, the crude extract of Aspergillus sp. showed mild antimicrobial activity against Bacillus subtilis, Klebsiella pneumoniae, and Candida albicans. The fungal extract showed good antioxidant activity at 500 µg/ml, with an inhibition of 72.1%. Also, at 100 µg/ml, the extract showed excellent cytotoxic activity against A2780 (sens) and A2780 (cisR), with growth inhibitions of 105.1% and 105.5% respectively. Two known pharmacologically active phenolic compounds (p-hydroxyphenyl acetic acid and ferulic acid) were isolated from the fermentation extract of the endophytic fungus. At 250 µg/ml, ferulic acid exhibited an excellent antioxidant activity with an inhibition of 90.4%, while an inhibition of 35.4% was recorded for p-hydroxyphenyl acetic acid. Ferulic acid also showed a mild antifungal activity at 500 µg/ml against A. niger with an IZD of 2 mm. p-Hydroxyphenyl acetic acid showed no antimicrobial activity. These results further confirm the potentials of endophytic fungi associated with Nigerian plants as source of bioactive compounds with pharmaceutical or industrial applications.
DOI: http://dx.doi.org/10.5281/zenodo.140498
Active case finding and evaluation of IL-6 production among household contacts of pulmonary tuberculosis patients in a high disease setting
Background: Tuberculosis (TB) is a top infectious disease killer worldwide and remains a huge public health concern. However, most TB case findings are limited to self-referral (passive case finding), when individuals develop symptoms of TB. Only 15% of disease burden in Nigeria are reported. In view of this, it is important to assess the latent and active disease burden amongst HHC of TB patients suffering from pulmonary TB. In addition, it has been suggested that IL-6 levels could be used as a prognostic marker in exposed individuals. IL-6 levels were assessed in this cohort.Methods: A total of 205 subjects participated in this study, comprising 62 pulmonary TB index cases and 143 of their household contacts. Also, 54 apparently healthy subjects were recruited to serve as controls. Active case finding was performed amongst the HHC, using sputum and blood samples; they were tested for active TB. Blood samples were also collected for measuring IL-6 levels.Results: Findings reveal 6.3% previously undiagnosed active TB among the HHC of the TB patients and a significantly higher number of latently infected TB cases compared to the control population (p=0.0078). There were significant differences when comparing HIV co-infected index group to their HIV negative counterparts (P=0.032). Significantly different IL-6 levels were found among the study groups and sub-groups (p<0.0001), with significantly higher levels in TB mono-infection compared to in TB/HIV co-infection (p=0.031).Conclusions: These results demonstrate the importance of active TB case finding for TB control and the possible role of IL-6 as a diagnostic marker in TB control
UV-mediated enhancement of antibacterial secondary metabolites in endophytic Lasiodiplodia theobromae
In the science of drug discovery, ultraviolet (UV) irradiation has been applied to induce mutagenesis in fungi to provide possibilities for the stimulation or enhancement of fungal biosynthetic capabilities. This study was carried out to evaluate the effect of UV radiation on the biosynthesis of antibacterial secondary metabolites in an endophytic Lasiodiplodia theobromae. Using standard methods, the fungus was isolated from healthy leaves of Cola acuminata and identified based on PCR amplification and genomic sequencing of the internal transcribed spacer (ITS) region. Cultures of L. theobromae were exposed to UV radiation at different time intervals of 1, 2 and 5 min. The fungus was subjected to solid-state fermentation in rice medium before and after UV treatments. The fungal secondary metabolites were extracted and tested for antibacterial activity using the agar diffusion method. Compounds present in the obtained extracts were identified by HPLC and GC-MS analysis. At a concentration of 1 mg/ml, the extract of the wild type L. theobromae (untreated) was observed to only inhibit Staphylococcus aureus, with an IZD of 12 mm. However, the extract of UV-treated L. theobromae (2 min) inhibited S. aureus, Escherichia coli and Pseudomonas aeruginosa with an IZD of 10 and 4 mm respectively. A wide array of compounds in the phenolics, fatty acids, alkaloids and alkanes classes were identified in the UV-treated and untreated fungal extracts. Overall, UV treatments of L. theobromae stimulated the production of seventeen (17) new compounds that were not detected in the untreated strain. The study confirms UV irradiation as an effective method for stimulating microbial biosynthesis of new bioactive compounds, indicating a promising and potentially abundant source of new drug compounds from microorganisms
Musculoskeletal imaging authority, levels of training, attitude, competence, and utilisation among clinical physiotherapists in Nigeria: a cross-sectional survey
BACKGROUND: Direct-access physiotherapy practice has led to a global review of the use of differential-diagnostic modalities such as musculoskeletal imaging (MI) in physiotherapy. OBJECTIVE: To explore the MI authority, levels of training, attitude, utilisation, and competence among clinical physiotherapists in Nigeria. METHODS: This national cross-sectional study analysed a voluntary response sample of 400 Nigerian physiotherapists that completed the online version of the Physiotherapist’s Musculoskeletal Imaging Profiling Questionnaire (PMIPQ), using descriptive statistics, Spearman’s correlation, Mann-Whitney U, Kruskal-Wallis, and Friedman’s ANOVA tests. RESULTS: Of the 400 participants, 93.2% believed that physiotherapists should use MI in clinical practice. However, only 79.8% reported having MI authority in their practice settings. The participants’ median (interquartile range) levels of training =10 (24) and competence =16 (24) were moderate. Nonetheless, levels of training (χ2 [15] = 1285.899, p = 0.001), and competence (χ2 [15] = 1310.769, p < 0.001) differed across MI procedures. The level of training and competence in x-ray referral and utilisation was significantly higher than magnetic resonance imaging, computed tomography scan, ultrasonography, scintigraphy, and dual-energy x-ray absorptiometry, in that order (p < 0.05). There was a significant positive correlation between the levels of training and competence (rho =0.61, p < 0.001). The participants had a positive attitude =32 (32) and occasionally used MI in clinical practice =21 (28). CONCLUSION: Majority of the respondents believed they had MI authority although there was no explicit affirmation of MI authority in the Nigerian Physiotherapy Practice Act. Participants had a positive attitude towards MI. However, levels of MI training, competence, and utilisation were moderate. Our findings have legislative and curriculum implications
Chapter 31 - Application of nanochitosan in tagging and nano-barcoding of aquatic and animal meats
Nanochitosans obtained from crustacean shells are biodegradable and biocompatible offering valuable functional, nutritional, and binding properties. Their low toxicity favors diverse industrial applications in various research models and can enable their use in the tagging of commercially sold aquatic and animal meat, easily contaminated by microbial sources during packaging, storage, and transportation. In this capacity, nanochitosans have been applied in fingerprinting for tracking and identifying the manufacturing and expiry dates of commercially sold meats and fish, as well as delivery of antioxidants and antimicrobials in these food products without affecting product consistency, composition, and organoleptic property. This chapter reviews current research on chitosan-based nanoparticles as barcodes and biosensors in tagging and monitoring aquatic and animal meats; and highlights methods of fish tagging and coding, and the benefits as well as the properties of materials used as biosensors in nano-barcoding of fish and meat
Validation of coronavirus-2019 phobia scale using preschool practitioners in urban and rural communities in Nigeria Implication for educational sociologists
Coronavirus-2019 (COVID-19) emerged in December 2019, causing significant changes in people’s social lives and other human
activities. The outbreak halted educational activities throughout the world. The Nigerian experience was unique in that most people
were skeptical about the pandemic’s existence. This practice contributed to the Nigerian people’s fear of the COVID-19 outbreak.
However, in Nigeria, there has never been a validated or established Covid-19 phobia scale, necessitating this study.
This study was a pure validation study on COVID-19 phobia scale (C19PS). The study area was south-east states and a sample of
386 preschool practitioners in urban and rural communities of South East States, Nigeria participated in the study. The eligibility
criteria include being a preschool teacher and demonstrating signs of COVID-19 phobia. The validation of the C19PS was done by
subjecting the data gathered to principal axis factoring analysis with varimax rotation. The model fit for the data was tested using
root mean square error of approximation and comparative fit index.
It was found that the Kaiser-Meyer-Olkin value of .845 for the measure of the adequacy of the sample size. There was also a
significant Bartlett’s test of sphericity (P<.05). This implies that the correlation matrix for the C19PS is not an identity matrix. It was
revealed that C19PS had good overall reliability (a=.896) and model fit (Root mean square error of approximation=.042,
comparative fit index=.943) in a sample of Nigerian preschool practitioners.
As a result, C19PS was recommended as a trustworthy tool for identifying persons who suffer from COVID-19 phobia.https://www.journals.elsevier.com/medicineam2023Science, Mathematics and Technology Educatio