A comparison of the antioxidant activity with the Total Phenolic and Total Flavonoid Contents of the leaves and stem-bark of Anogeissus leiocarpa (DC.) Guill& Pirr. (Combretaceae)

Background: Anogeissus leiocarpa is used in traditional medical practice for the treatment of many diseases such as asthma, malaria, diabetic ulcers, dysentery,  blood clots, cough, tuberculosis, parasitic infections and general body pain. Free radicals are known to play a major role in the aetiology of several these diseases. Thus, radical scavenging as well as antioxidant potentials of the plant are good indications of its effectiveness in disease management.Objective: This study evaluates the antioxidant activity of the extracts from the leaves and stem bark of Anogeissus leiocarpa..Materials and Methods: Dried powdered leaves and bark were extracted with  methanol. The extracts were subjected to DPPH Free Radical Scavenging Activity, Ferric Reducing Antioxidant Power (FRAP), Total Antioxidant Capacity (TAC), ABTS Cation Decolourization, Cupric Reducing Antioxidant Capacity (CUPRAC), and Metal Chelating (MC) assays. The Total Phenolic Content (TPC), Total Flavonoid Content (TFC), total anthocyanidin Content (tAC), and proanthocyanidin Content (pAC) were also determined.Results: The extract and ethyl acetate fraction of the stem bark had more  antioxidant potential. The stem bark extract had an IC50 of 12.44+2.32 in the  DPPH radical scavenging assay, the ferric reducing antioxidant power of 98.43+1.63 and ABTS radical decolourisation activity of 96.55+0.54 while the DPPH radical scavenging activity and the ABTS radical decolourisation effect for ascorbic acid and trolox were 39.25+ 1.11 and 379.24 + 0.08 respectively. The Total Antioxidant Capacity as well as the Total Phenolic Content and Total Flavonoid Content was highest in the ethyl acetate fraction of the bark.Conclusion: The extract of A. leiocarpa showed good antioxidant activity which  compares well with the high phenolic content and thus have potential for use in the management of several diseases.Keywords: Anogeissus leiocarpa. Antioxidant, Radical Scavenging, Total Phenolic, Total Flavonoi

Cognitive-enhancing properties of Morinda lucida (Rubiaceae) and Peltophorum pterocarpum (Fabaceae) in scopolamine-induced amnesic mice

Background: Cognitive disorders associated with aging have been successfully managed by African traditional medical practitioners using various plants. This study evaluated the cognitive enhancing potentials of Morinda lucida (L) Rubiaceae and Peltophorum pterocarpum (DC) ex. K Heyne in scopolamine induced amnesic animals.Materials and Methods: The anti-amnesic activity of the ethyl acetate extracts of Morinda lucida and Peltophorum pterocarpum at doses of 4 mg/kg, 6 mg/kg and 8 mg/kg were assessed in scopolamine induced amnesic mice using Morris water maze test model. Effect of the extracts on the histology of the hippocampus was also evaluated.Results: The ethyl acetate extract of Morinda lucida and Peltophorum pterocarpum ameliorated scopolamine induced memory deficit in the animals under study. There was no effect of the extract on the histology of the hippocampus. However, there was an increase in the density of cells in the hippocampus of treated group as compared to the untreated.Conclusion: Morinda lucida and Peltophorum pterocarpum showed considerable enhancement of cognition in scopolamine induced amnesic mice.Keywords: Morinda lucida, Peltophorum pterocarpum, Morris water maze, Scopolamine, Hippocampu

Plants-derived neuroprotective agents: Cutting the cycle of cell death through multiple mechanisms

Neuroprotection is the preservation of the structure and function of neurons from insults arising from cellular injuries induced by a variety of agents or neurodegenerative diseases (NDs). The various NDs including Alzheimer’s, Parkinson’s, and Huntington’s diseases as well as amyotropic lateral sclerosis affect millions of people around the world with the main risk factor being advancing age. Each of these diseases affects specific neurons and/or regions in the brain and involves characteristic pathological and molecular features. Hence, several in vitro and in vivo study models specific to each disease have been employed to study NDs with the aim of understanding their underlying mechanisms and identifying new therapeutic strategies. Of the most prevalent drug development efforts employed in the past few decades, mechanisms implicated in the accumulation of protein-based deposits, oxidative stress, neuroinflammation, and certain neurotransmitter deficits such as acetylcholine and dopamine have been scrutinized in great detail. In this review, we presented classical examples of plant-derived neuroprotective agents by highlighting their structural class and specific mechanisms of action. Many of these natural products that have shown therapeutic efficacies appear to be working through the above-mentioned key multiple mechanisms of action

Novel cholinesterase inhibitory effect of α-spinasterol isolated from the leaves of Acacia auriculiformis A. CUNN Ex. Benth (Fabaceae)

Purpose: To investigate the in vitro anticholinesterase, α-glucosidase and antioxidant activities of α-spinasterol isolated from Acacia auriculiformis leaves.Methods: The powdered leaves of Acacia auriculiformis were extracted with 70 % ethanol and the dried hydroalcoholic extract was suspended in water and partitioned with ethyl acetate and n-butanol to give their soluble fractions. The in vitro inhibitory activities of α-spinasterol were determined against cholinesterase and, α-glucosidase enzymes, and free radical scavenging potentials using (1,1-diphenyl-2-picrylhydarzyl (DPPH) and 2,2-azino-bis (3-Ethylbenzothiazoline-6-sulphonic acid (ABTS) antioxidantassays.Results: The compound, α-spinasterol, exhibited moderate anticholinesterase activity (IC50 value of 44.19±2.59 μg/mL which was significantly  different at (p < 0.05) when compared to the standard galanthamine (IC50 value of 1.73 ± 1.10 μg/mL). It also displayed a good α-glucosidase  inhibitory activity with IC``` value of 8.65 ± 1.71μg/mL which was not significantly different when compared to the standard, acarbose with IC50 value of 2.79±0.81 μg/mL. This compound, however, exhibited weak free radical scavenging activities at 26.93 ± 0.00 and 35.16 ±.0.26 % inhibition of DPPH+ and ABTS+ radicals as compared to ascorbic acid and Trolox (73.88 ± 0.04 and 99.82 ± 0.00%) respectively.Conclusion: The results show that α-spinasterol isolated from Acacia auriculiformis exerts potent inhibitory effect against cholinesterase enzyme which might serve as a lead in the search for drugs against Alzheimer disease and diabetes mellitus. Keywords: Acacia auriculiformis, α-Spinasterol, Galanthamine, Acarbose, Trolox, Ascorbic aci

COGNITIVE-ENHANCING PROPERTIES OF MORINDA LUCIDA (RUBIACEAE) AND PELTOPHORUM PTEROCARPUM (FABACEAE) IN SCOPOLAMINE-INDUCED AMNESIC MICE

Background: Cognitive disorders associated with aging have been successfully managed by African traditional medical practitioners using various plants. This study evaluated the cognitive enhancing potentials of Morinda lucida (L) Rubiaceae and Peltophorum pterocarpum (DC) ex. K Heyne in scopolamine induced amnesic animals. Materials and Methods: The anti-amnesic activity of the ethyl acetate extracts of Morinda lucida and Peltophorum pterocarpum at doses of 4 mg/kg, 6 mg/kg and 8 mg/kg were assessed in scopolamine induced amnesic mice using Morris water maze test model. Effect of the extracts on the histology of the hippocampus was also evaluated. Results: The ethyl acetate extract of Morinda lucida and Peltophorum pterocarpum ameliorated scopolamine induced memory deficit in the animals under study. There was no effect of the extract on the histology of the hippocampus. However, there was an increase in the density of cells in the hippocampus of treated group as compared to the untreated. Conclusion: Morinda lucida and Peltophorum pterocarpum showed considerable enhancement of cognition in scopolamine induced amnesic mice

QUALITY EVALUATION OF POZA BITTERS, A NEW POLY HERBAL FORMULATION IN THE NIGERIAN MARKET

Background: Development of a quality assurance system for new botanicals for health and nutrition is challenging. Producers must understand consumer demands and develop methods of production that meet those demands of product quality and efficacy, which exceeds or corresponds to international standards. The present article is an attempt to evaluate the quality of Poza bitters, a new polyherbal formulation, used as a purgative, by physical and analytical methods. Materials and Methods: Poza bitters was screened for the presence of secondary metabolites and microbial contamination. The pH, micronutr-ient and heavy metal composition analysis, as well as chromatographic fingerprinting using thin layer chromatography and high performance liquid chromatography were also carried out. Results: Phytochemical analysis revealed the presence of alkaloids, saponins, tannins, and flavonoid glycosides. The pH value was 3.66. The sample assayed had acceptable level of microorganisms and toxic metals were absent. Thin layer chromatography of the sample using methanol/water/acetic acid (30:70:5) showed three spots with Rf values similar to some of references used. High performance liquid chromatography fingerprint showed two retention times of poza bitters which were not similar to those of the reference standards: hesperidin and narigenin, thus suggesting the absence of these flavonoids in poza bitters. Conclusion: Poza bitters comply with WHO microbial standard as well as standards for heavy metals. Also, the presence of Aloe ferox and citrus was confirmed on TLC

Cholinesterase inhibitory activity and structure elucidation of a new phytol derivative and a new cinnamic acid ester from Pycnanthus angolensis

AbstractThe leaves of Pycnanthus angolensis (Welw.) Warb., Myristicaceae, are used as memory enhancer and anti-ageing in Nigerian ethnomedicine. This study aimed at evaluating the cholinesterase inhibitory property as well as isolates the bioactive compounds from the plant. The acetylcholinesterase and butyrylcholinesterase inhibitory potentials of extracts, fractions, and isolated compounds were evaluated by colorimetric and TLC bioautographic assay techniques. The extract inhibited both enzymes with activity increasing with purification, ethyl acetate fraction being most active fraction at 65.66±1.06% and 49.38±1.66% against acetylcholinesterase and butyrylcholinesterase, respectively while the supernatant had 77.44±1.18 inhibition against acetylcholinesterase. Two new bioactive compounds, (2E, 18E)-3,7,11,15,18-pentamethylhenicosa-2,18-dien-1-ol (named eluptol) and [12-(4-hydroxy-3-methyl-oxo-cyclopenta-1,3-dien-1yl)-11-methyl-dodecyl](E)-3-(3,4-dimethylphenyl)prop-2-enoate (named omifoate A) were isolated from the plant with IC50 of 22.26μg/ml (AChE), 34.61μg/ml (BuChE) and 6.51μg/ml (AChE), 9.07μg/ml (BuChE) respectively. The results showed that the plant has cholinesterase inhibitory activity which might be responsible for its memory enhancing action, thus justifying its inclusion in traditional memory enhancing preparation

Chemical composition and termiticidal activity of Khaya ivorensis stem bark extracts on woods

The genus Khaya is extractives rich, but the extractives in the stem bark are among the most abundant, accessible and utilised materials in Nigeria. These extractives are of considerable interest for wood protection because of their pesticidal properties. In this study, the chemical constituents of Khaya ivorensis stem bark and their termiticidal activity were investigated on Triplochiton scleroxylon and Vitex doniana woods. Spectrophoto-metric and Forlin-Ciocalteu analyses showed that Khaya ivorensis stem bark contained total: alkaloids 38.98±0.02 mg/g, flavonoids 0.37±0.02 mg/g, phenol 50.62±0.11 mg/g, saponins 156.31±0.76 mg/g, and tannins 59.95±0.54 mg/g. Field tests demonstrated that the extract from Khaya ivorensis stem bark had significant termiticidal activity at tested concentrations compared to the control. The results indicated that Khaya ivorensis stem bark has potential as a natural agent for termite control