1,720,963 research outputs found
Molecular Identification of Fungal Complex Associated with Stored Maize Grains Vended in Some Local Government Areas of Adamawa State, Nigeria
Full text linkMaize is a crucial global crop but remains highly vulnerable to fungal contamination, which poses serious threats to food safety and agricultural productivity. This study aimed to identify fungal species associated with maize samples from Adamawa State, Nigeria, using morphological and molecular techniques. Morphological analysis facilitated genus-level identification, while rDNA ITS sequencing provided precise species-level classification. The identified fungal species included Lichtheimia ramosa, Aspergillus latus, Aspergillus flavus, Amesia atrobrunnea, and Cladosporium cladosporioides. Among them, Aspergillus flavus was the most prevalent (48.1%), followed by A. latus (22.1%), L. ramosa (14.3%), C. cladosporioides (12.9%), and A. atrobrunnea (2.6%). Yola North recorded the highest level of fungal contamination. Growth rate analysis showed that L. ramosa exhibited the fastest growth, while A. atrobrunnea had the slowest. Molecular identification confirmed the fungal species, with ITS sequences displaying 81% to 95% similarity to reference strains. Phylogenetic analysis further clarified the evolutionary relationships among the isolates. The dominance of Aspergillus species, particularly A. flavus, raises concerns due to their mycotoxin-producing capabilities, which pose health risks and compromise food safety. While these findings align with previous reports on fungal contamination in stored grains, they differ from studies highlighting Fusarium and Penicillium as dominant contaminants in other regions. This study emphasizes the need for accurate fungal identification, improved storage techniques, and advanced molecular tools to mitigate contamination. These insights are essential for enhancing food security, promoting agricultural sustainability, and safeguarding public health in maize-reliant regions such as Nigeria
Phytochemical, Acute toxicity, and Antibacterial Activity of Tamarindus indica Against Antimicrobial-Resistant Staphylococcus aureus
Full text linkThe escalating public health crisis of antimicrobial resistance (AMR), driven by pathogens like methicillin-resistant Staphylococcus aureus (MRSA), demands an urgent expansion of the therapeutic arsenal. This study provides a comprehensive scientific validation of Tamarindus indica L., a plant with extensive ethnobotanical uses, by systematically evaluating its phytochemical composition, antibacterial efficacy, and acute toxicity profile. Phytochemical analysis revealed that methanol extraction was superior to n-hexane, yielding a rich array of bioactive compounds from the leaves, including alkaloids, flavonoids, saponins, and phenolic compounds. Quantitative assessment confirmed substantial levels of key metabolites, with saponins (550–1400 mg/100g), total phenolics (800–2000 mg/100g), and flavonoids (450–1100 mg/100g) being the most abundant. Antibacterial assays demonstrated that the methanolic extract possessed potent, strain-specific activity against clinical isolates of S. aureus. A notable finding was the significant susceptibility of one strain (SaD), which showed a zone of inhibition of 23.00 mm at 80 mg/mL, exceeding the activity of the cefoxitin control. The methanol fruit extract exhibited Minimum Inhibitory Concentration (MIC) values between 4.69 and 9.38 mg/mL. Crucially, the Minimum Bactericidal Concentration (MBC) was identical to the MIC for most strains, indicating a primarily bactericidal, rather than bacteriostatic, mode of action. In stark contrast, the n-hexane extract showed minimal efficacy, highlighting the critical influence of solvent polarity on the recovery of antibacterial constituents. A pivotal component of this research was the toxicological evaluation. An acute oral toxicity study conducted in rats established an excellent safety profile, with no mortality or significant adverse effects observed at the limit dose of 5000 mg/kg, classifying the extract as practically non-toxic according to OECD guidelines. This finding confirms a wide therapeutic window for potential applications. In conclusion, this study definitively links the traditional use of Tamarindus indica to a scientifically verified, bactericidal phytochemical profile effective against S. aureus and a compelling safety margin. These results firmly position T. indica as a promising candidate for the development of standardized herbal medicines to address the growing threat of antibiotic-resistant infections
Phytochemical Analysis, In-vitro, and In-silico Antibacterial Activity of Stembark Extract of Anogeissus leiocarpus (DC) Guill and Perr
Full text linkBacterial infections subsequently leading to antibiotic resistance has been a leading cause of mortality and morbidity worldwide especially in developing countries with high poverty rate and poor healthcare system. Thus, prompting the prospect in alternative therapy such as medicinal plants. In the present study, we evaluated the antibacterial action of stem bark extract of Anogeissus leiocarpus (AL) Guill and Perr. as applied in folkloric medicine for antibacterial purposes. The phytochemicals present in the plant extract were identified and quantified, followed by the determination of the antibacterial effects of the extract against Escherichia coli and Staphylococcus aureus. Molecular docking study was carried out to ascertain the inhibitory effects of compounds from AL against bacterial enzymes. Alkaloids (7.17% ±0.60), saponins (11.33% ±3.18), and flavonoids (31.01% ±4.04) were detected. A maximum ZI was observed for E. coli compared to S. aureus at the highest extract concentration (100 mg/mL) with amoxicillin having superior ZI at 50 mg/mL concentration. The MIC against E. coli and S. aureus were 12.5 mg/mL and ≤ 6.25 mg/mL respectively while the MBC was>100 mg/mL and 100 mg/mL respectively. Among the identified compounds, IX exhibited the least binding affinity (BA) (7.2 kcal/mol) and inhibition constant (Ki) (5 µM) against UDP-N-acetylglucosamine Enolpyruvyl Transferase (Mur A) compared to all the other targets. AL demonstrated antibacterial activity evidenced by the bacterial growth inhibition, bactericidal potential, and in-silico study revealing high affinity of the bacterial enzymes for the identified compounds, thereby supporting the acclaimed antibacterial use of the plant in folkloric medicine
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Utilization of Eco-Friendly Iron Oxide Nanoparticles for Wastewater Treatment
Full text linkThis study investigates the potential of green-synthesized Iron II Oxide (Fe2O3) nanoparticles for remediating wastewater from River Benue, Nigeria, focusing on removing lead (Ld) pollutants. The nanoparticles were synthesized using Annona squamosa leaf extract, offering an eco-friendly alternative to conventional remediation methods. The wastewater sample, collected from River Benue in Jimeta-Yola, was analyzed using FT-IR, SEM, and atomic absorption spectroscopy. FT-IR analysis identified functional groups like alcohol O-H and conjugated alkene C=C, confirming the role of plant metabolites in nanoparticle synthesis and stabilization. SEM imaging revealed cubical Fe2O3 nanoparticle sizes ranging from 25 to 34 nm, stabilized by the plant extract. The remediation process tested varying nanoparticle concentrations (100, 500, 1000, and 1500 ppm) and contact times (60, 120, and 180 minutes) at pH 8.90 and 21.33 K. The highest adsorption efficiency was observed at 1500 ppm over 180 minutes, reducing lead levels from 0.69 mg/L to 0.02 mg/L due to increased chelating sites. Lower concentrations (1000, 500, and 100 ppm) also demonstrated significant adsorption, with lead levels dropping to 0.21, 0.32, and 0.50 mg/L, respectively. The study highlights the advantages of Fe2O3 nanoparticles, including simplicity, rapid production, environmental safety, and a high surface area for effective pollutant adsorption. This green synthesis approach is more sustainable and operationally simpler than tradisional methods, avoiding the environmental risks associated with conventional techniques. The findings suggest that Fe2O3 nanoparticle is promise for efficient and sustainable wastewater purification, offering a viable alternative to existing water treatment technologies. This research underscores the potential of eco-friendly nanomaterials in addressing heavy metal pollution, particularly in developing regions
Antibacterial Potential of Ximenia americana L. Olacaceae: Molecular Docking, Molecular Dynamics, and ADMET Prediction
Full text linkIntroduction: The devastating effect of persistent and recurrent bacterial infections coupled with antibiotic resistance is a driving force for prospects into alternative antibacterial therapeutics to achieve treatment. This study investigates the antibacterial potential of Ximenia americana (XA) via molecular docking, molecular dynamics, and ADMET approach.
Materials and methods: The ligands and target were downloaded from respective databases and docked using PyRx software followed by molecular dynamics simulation (MDS) with iMOD and CABflex 2.0 online servers then ADMET, drug likeness, lead likeness, and medicinal chemistry predictions of the top docked ligands using pkCSM and SwissADME online servers.
Results: Stigmasterol exhibited the lowest binding affinity and inhibition constant respectively with all the targets; enoyl-acyl-carrier-protein reductase (-7.1 kcal/mol and 6.16 µM), Penicillin-binding Protein 2X (-8.8 kcal/mol and 0.35 µM), dihydrofolate reductase (-9.6 kcal/mol and 0.09 µM), dihydropteroate Synthase (-7.8 kcal/mol and 1.89 µM), UDP-N-acetylglucosamine enolpyruvyl transferase (-7.1 kcal/mol and 6.16 µM), and topoisomerase IV (-7.8 kcal/mol and 1.89 µM). The MDS showed several cluster displacements and residue fluctuations with the docked targets with higher residue fluctuations observed for enoyl-acyl-carrier-protein reductase (11.33 ?), Penicillin-binding Protein 2X (4.67 ?), dihydrofolate reductase (3.61 ?), dihydropteroate Synthase (4.97 ?), UDP-N-acetylglucosamine enolpyruvyl transferase (3.38 ?), and topoisomerase IV (4.35 ?). 4,4-Dimethylcyclohex-2-en-1-ol exhibited superior overall ADMET properties, oral bioavailability, drug-likeness, and medicinal chemistry.
Conclusion: Conclusively, Stigmasterol and 4,4-Dimethylcyclohex-2-en-1-ol might be responsible for the antibacterial effect of XA. Although the latter showed better interaction with the target proteins, the former showed better ADMET properties, oral bioavailability, drug-likeness, and medicinal properties. However, improvement in these properties might enhance their antibacterial activity
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Antibacterial And Synergistic Potential of Hibiscus sabdariffa and Zingiber officinale Against Multidrug-Resistant Bacteria
Full text linkAntimicrobial resistance (AMR) is a global health challenge, particularly in developing regions where access to effective drugs is constrained. Medicinal plants provide an alternative due to their affordability, availability, and wealth of bioactive compounds. This study investigated the antibacterial properties of Zingiber officinale (ginger) and Hibiscus sabdariffa (roselle), both widely used in African traditional medicine, against selected bacterial pathogens. Methanolic extracts were prepared from dried rhizomes of ginger and calyces of roselle, and concentrations of 100%, 95%, 90%, and 85% were tested. Antibacterial activity was determined against Staphylococcus aureus, Escherichia coli, and Pseudomonas sp. using agar well diffusion. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were established by serial dilution and subculture techniques. Statistical significance was assessed using one-way ANOVA and Duncan’s multiple range test at p < 0.05. Phytochemical analysis revealed steroids, terpenoids, and flavonoids in both plants. Ginger additionally contained saponins, alkaloids, tannins, and carbohydrates, whereas roselle uniquely presented cardiac glycosides. Antibacterial activity increased with concentration, with the 100% extracts showing the highest inhibition zones. The combined extract consistently produced larger inhibition zones compared to the individual extracts (p < 0.05). Ginger exhibited the strongest individual activity against S. aureus, while the combined extract was most effective against E. coli. Pseudomonas sp. was the least susceptible. MIC values confirmed these observations: S. aureus was the most sensitive (25 mg/mL), while E. coli and Pseudomonas sp. each recorded 50 mg/mL. MBC values were uniformly 50 mg/mL across all test organisms. The results demonstrate that ginger and roselle possess significant antibacterial properties, with ginger showing superior individual efficacy and roselle providing complementary metabolites that enhanced combination effects. Their synergistic action supports traditional polyherbal therapy and indicates potential as cost-effective, plant-based interventions against AMR. The findings underscore the need for further research to develop standardized formulations for therapeutic application
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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