Browsing by Author "Vigbedor, Bright Yaw"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Isolation and Identification of Flavanone Derivative Eriodictyol from the Methanol Extract of Afzelia africana Bark and Its Antimicrobial and Antioxidant Activities
    (Evidence-Based Complementary and Alternative Medicine, 2023) Vigbedor, Bright Yaw; Osei Akoto, Clement; Neglo, David; 0000-0003-3955-9883; 0000-0003-2717-2753; 0000-0003-2547-5021
    Background. Afzelia africana is a plant species with well-documented ethnobotanical and medicinal properties. The plant is reported to have various secondary metabolites and had been applied for the treatment of various diseased conditions. Objectives. The study objectives include fractionation, isolation, purifcation, and characterization of eriodictyol from the bark of A. africana, and the determination of its antimicrobial and antioxidant activities. Methodology. Te series of methodologies that were employed include fractionations and purifcation (column chromatography), characterization (HPLC, LC-MS, IR, 1 H, 13C, DEPT-135, HSQC, and HMBC), antimicrobial assays (microbroth dilution and checkerboard assay), and antioxidant activities assays (ABTS and DPPH scavenging capacity). Results. The study reports the identifcation and characterization of eriodictyol from the bark of A. africana which exhibited potent antioxidant activities against ABTS and DPPH radicals with scavenging capacities (SC50) of 2.14 ± 0.05 and 2.51 ± 0.06 µg/mL, respectively. The compound exhibited its antimicrobial activity by reporting good bacteriostatic activities (MBC/MIC> 4) against Staphylococcus aureus (SA), methicillin-resistant Staphylococcus aureus (MRSA), and fuconazole-resistant Candida albicans (CA2). Moreover, a broad spectrum of bactericidal efects (MBC/MIC ≤ 4) was reported against Streptococcus mutans (SM), Escherichia coli (EC), Bacillus subtilis (BS), Klebsiella pneumonia (KP), Pseudomonas aeruginosa (PA), Salmonella typhi (ST), and standard Candida albicans (CA1). The compound further exhibited synergistic efects against EC, KP, ST, and MRSA; ST; and CA2 when combined with ciprofoxacin, tetracycline, and nystatin, respectively. However, antagonistic efects were observed against PA and CA1 when combined with ciprofoxacin and ketoconazole, respectively. Conclusion. Te study reports for the frst time the identifcation of eriodictyol from the bark of A. africana which exhibited signifcant antioxidant and antimicrobial properties.
  • No Thumbnail Available
    Item
    Repellency Potential, Chemical Constituents of Ocimum Plant Essential Oils, and Their Headspace Volatiles against Anopheles gambiae s. s., Malaria Vector
    (Hindawi, 2023-04) Acheampong, Akwasi; Osei-Owusu, Jonathan; Heve, William K.; Aidoo, Owusu Fordjour; Opoku, Maxwell Jnr; Apau, Joseph; Dadzie, Kodwo Ninsin; Vigbedor, Bright Yaw; Awuah-Mensah, Kwaafo Akoto; Appiah, Margaret; Birkett, Michael; Hooper, Antony; 0000-0003-2481-1126
    African malaria mosquitoes (Anopheles gambiae sensu stricto) transmit a malaria parasite (Plasmodium falciparum) to humans. )ecurrent control strategies for the vector have mainly focussed on synthetic products, which negatively impact the environment and human health. Given the potential use of environmentally friendly plant-derived volatiles as a control, this work aims to examine and compare the repellency potential of essential oils and headspace volatiles from Ocimum gratissimum, Ocimum tenui2orum, and Ocimum basilicum and their chemical compositions. )e repellency potential and chemical composition of the plants were achieved by using the protected arm-in-cage method and gas chromatography-mass spectrometry (GC-MS) analysis. Among the three Ocimum species, both the essential oils and the headspace volatiles from O. tenui2orum achieved the longest repellency time lengths of 90–120 minutes. One hundred and one (101) chemical constituents were identi6ed in the headspace volatiles of the three Ocimum spp. Nonetheless, (−)-camphor, (E)-c-bisabolene, terpinolene, 4-chamigrene, cubedol, (E)-farnesol, germacrene D-4-ol, viridi9orol, c-eudesmol, tetracyclo [6.3.2.0 (2,5).0(1,8)] tridecan-9-ol, 4,4-dimethyl, 5-eudesmol, isolongifolol, and endo-borneol were unique only to O. tenui2orum headspace volatiles. Either essential oils or headspace volatiles from O. tenui2orum could o>er longer protection time length to humans against An. gambiae. )ough 6eld studies are needed to assess the complementarity between the chemical constituents in the headspace volatiles of O. tenui2orum, our observations provide a foundation for developing e>ective repellents against An. gambiae.