Browsing by Author "Ekpo, Okobi Eko"

Now showing 1 - 6 of 6
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    Comparative study of the antioxidant constituents, activities and the gc-ms quantification and identification of fatty acids of four selected helichrysum species
    (MDPI, 2022) Akinyede, Kolajo Adedamola; Hughes, Gail Denise; Ekpo, Okobi Eko
    Helichrysum Mill. (Asteraceae) is a plant genus comprising distinctively of aromatic plants of about 500–600 species. Since most of these plants have not been previously studied, extensive profiling helps to validate their folkloric uses and determine their potential value as sources of plantderived drug candidates. This study, therefore, aims to investigate the antioxidant activity (DPPH, NO, FRAP); total antioxidant capacity, total phenolic, total flavonoid, and fatty acid compositions of the aqueous acetone extracts from four Helichrysum plants namely, Helichrysum pandurifolium, Helichrysum foetidum, Helichrysum petiolare, and Helichrysum cymocum. The results obtained showed that the H. cymocum extract had the best DPPH radical scavenging activity (IC50 = 11.85 ± 3.20 µg/mL) and H. petiolare extract had the best nitric oxide scavenging activity (IC50 = 20.81 ± 3.73 µg/mL), while H. pandurifolium Schrank extract (0.636 ± 0.005 µg/mL) demonstrated the best ferrous reducing power, all of which are comparable with results from ascorbic acid used as the standard. The IC50 values of the radical scavenging activity ranged from 11.85–41.13 µg/mL (DPPH), 20.81–36.19 µg/mL (NO), and 0.505–0.636 µg/mL (FRAP), for all the plants studied. The H. petiolare has the highest total antioxidant capacity (48.50 ± 1.55 mg/g), highest total phenolic content (54.69 ± 0.23 mg/g), and highest total flavonoid content (56.19 ± 1.01 mg/g) compared with other species.
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    Cytotoxic and cell cycle arrest properties of two steroidal alkaloids isolated from Holarrhena floribunda (G. Don) T. Durand & Schinz leaves
    (BMC, 2019) Badmus, Jelili Abiodun; Ekpo, Okobi Eko; Hussein, A. A.
    The plant Holarrhena floribunda (H. floribunda; G. Don) is indigenous to sub-Saharan Africa and is traditionally used to treat several ailments. The present study was carried out to isolate and characterize bioactive compounds with anti-proliferative activity present in H. floribunda extracts. Compounds were isolated from H. floribunda using the bioassay-guided fractionation technique of repeated column chromatography and the step-wise application of the MTT reduction assay to assess antiproliferative bioactivity. The structures of the compounds were identified mainly using NMR. The effects of the isolated compounds on the viability, cell cycle and proliferation of human cancer cell lines (MCF-7, HeLa and HT-29) as well as the non-cancerous human fibroblast cell line (KMST-6) were investigated.
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    Ethnopharmacology, therapeutic properties and nutritional potentials of Carpobrotus edulis: A comprehensive review
    (MPDI, 2020) Akinyede, Kolajo Adedamola; Ekpo, Okobi Eko
    Carpobrotus edulis, formerly known as Mesembryanthemum edule L, belongs to the Aizoaceae family of plants. It is a facultative halophytic invasive medicinal and edible succulent plant that is native to South Africa and is distributed worldwide. Hitherto, this plant appears to be mainly known for its ornamental use in decorations, soil stabilization, and erosion control, and not for its many potential medicinal and nutritional benefits, thus suggesting its underutilization. This review presents cogent and comprehensive information on the distribution, ethnomedicinal use, phytochemistry, pharmacology, toxicology, and nutritional value of Carpobrotus edulis and provides the rationale for further pharmacognostic research that will validate its many folkloric medicinal and nutraceutical claims, and promote its standardization into a commercially available product.
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    In vitro evaluation of the anti-diabetic potential of aqueous acetone Helichrysum petiolare extract (AAHPE) with molecular docking relevance in diabetes mellitus
    (MDPI, 2021-12) Akinyede, Kolajo Adedamola; Oyewusi, Habeebat Adekilekun; Hughes, Gail Denise; Ekpo, Okobi Eko
    Diabetes mellitus (DM) is a chronic metabolic condition that can lead to significant complications and a high fatality rate worldwide. Efforts are ramping up to find and develop novel α-glucosidase and α-amylase inhibitors that are both effective and potentially safe. Traditional methodologies are being replaced with new techniques that are less complicated and less time demanding; yet, both the experimental and computational strategies are viable and complementary in drug discovery and development. As a result, this study was conducted to investigate the in vitro anti-diabetic potential of aqueous acetone Helichrysum petiolare and B.L Burtt extract (AAHPE) using a 2-NBDG, 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxy-D-glucose uptake assay. In addition, we performed molecular docking of the flavonoid constituents identified and quantified by liquid chromatography-mass spectrometry (LC-MS) from AAHPE with the potential to serve as effective and safe α-amylase and α-glucosidase inhibitors, which are important in drug discovery and development. The results showed that AAHPE is a potential inhibitor of both α-amylase and α-glucosidase, with IC50 values of 46.50 ± 6.17 (µg/mL) and 37.81 ± 5.15 (µg/mL), respectively. This is demonstrated by a significant increase in the glucose uptake activity percentage in a concentrationdependent manner compared to the control, with the highest AAHPE concentration of 75 µg/mL of glucose uptake activity being higher than metformin, a standard anti-diabetic drug, in the insulinresistant HepG2 cell line. The molecular docking results displayed that the constituents strongly bind α-amylase and α-glucosidase while achieving better binding affinities that ranged from ∆G = −7.2 to −9.6 kcal/mol (compared with acarbose ∆G = −6.1 kcal/mol) for α-amylase, and ∆G = −7.3 to −9.0 kcal/mol (compared with acarbose ∆G = −6.3 kcal/mol) for α-glucosidase. This study revealed the potential use of the H. petiolare plant extract and its phytochemicals, which could be explored to develop potent and safe α-amylase and α-glucosidase inhibitors to treat postprandial glycemic levels in diabetic patients.
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    In vitro evaluation of the antiproliferative activity of Carpobrotus edulis on human neuroblastoma cells
    (Elsivier, 2021) Ekpo, Okobi Eko; Enogieru, Adaze Bijou; Omoruyi, Sylvester Ifeanyi
    Neuroblastoma is a solid neuroendocrine tumour located outside the cranial cavity and contributes about 15% of all cancer‑associated deaths in children. Treatment of neuroblastoma is quite challenging and involves the use of chemotherapy, surgery and radiotherapy. Despite treatment strategies, systemic toxicity are setbacks to patient well-being, hence the need for a new and affordable approach. Medicinal plants are of importance in the field of drug discovery for cancer as some notable anti-cancer agents have been isolated from them. In the present study, the anti-cancer activity of aqueous extract of Carpobrotus edulis (C. edulis), a ground-creeping edible medicinal plant was investigated in SK-N-BE(2) and SH-SY5Y neuroblastoma cells. The effect of C. edulis on cell viability and survival was determined using MTT (3-[4,5-dimethylthiazol-2-yl]􀀀 2,5 diphenyltetrazolium bromide) and clonogenic assays respectively. Apoptosis was determined using a Caspase-9 assay kit and flow cytometry was used to measure intracellular reactive oxygen species (ROS) and depolarization of mitochondrial membrane potential. The results show that C. edulis inhibits cell viability (IC50 of 0.86 mg/ml and 1.45 mg/ml for SK-N-BE (2) and SHSY5Y cells respectively) and colony formation in the neuroblastoma cells as well as induce apoptosis, which is evidenced by an increase in caspase-9 activity in the cells. C. edulis also led to a loss of mitochondrial membrane potential and increased production of ROS. Collectively, these results suggest that C. edulis induces cell death via induction of mitochondrial-mediated apoptosis and accumulation of intracellular ROS, thus providing a rationale for further investigations.
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    Rutin as a potent antioxidant: implications for neurodegenerative disorders
    (Hindawi Publishing Corporation, 2018) Enogieru, Adaze Bijou; Haylett, William; Hiss, Donavon Charles; Bardien, Soraya; Ekpo, Okobi Eko
    A wide range of neurodegenerative diseases (NDs), including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and prion diseases, share common mechanisms such as neuronal loss, apoptosis, mitochondrial dysfunction, oxidative stress, and inflammation. Intervention strategies using plant-derived bioactive compounds have been offered as a form of treatment for these debilitating conditions, as there are currently no remedies to prevent, reverse, or halt the progression of neuronal loss. Rutin, a glycoside of the flavonoid quercetin, is found in many plants and fruits, especially buckwheat, apricots, cherries, grapes, grapefruit, plums, and oranges. Pharmacological studies have reported the beneficial effects of rutin in many disease conditions, and its therapeutic potential in several models of NDs has created considerable excitement. Here, we have summarized the current knowledge on the neuroprotective mechanisms of rutin in various experimental models of NDs. The mechanisms of action reviewed in this article include reduction of proinflammatory cytokines, improved antioxidant enzyme activities, activation of the mitogen-activated protein kinase cascade, downregulation of mRNA expression of PD-linked and proapoptotic genes, upregulation of the ion transport and antiapoptotic genes, and restoration of the activities of mitochondrial complex enzymes. Taken together, these findings suggest that rutin may be a promising neuroprotective compound for the treatment of NDs.