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

Comparative Evaluation of Antioxidant Properties of Methanol Extracts of Allium cepa bulb, Allium cepa bulb peels and Allium fistulosum.

Medicinal plants have protective effects against many physiological diseases because of their phytochemical components which are better antioxidants. This study was aimed at comparing the in vitro antioxidant activity, phenolic and flavonoid content of the methanol extracts of Allium cepa bulb, Allium cepa bulb peel and Allium fistulosum. The antioxidant activity was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), iron chelating activity and molybdate ion reduction assays. The total flavonoid and total phenolic content (TPC) were carried out using aluminium chloride and Folin-Ciocalteu assay respectively. The results showed that A. cepa bulb peel has the highest phenolic content and the antioxidant activity while the A. fistulosum showed the least. Furthermore, the total flavonoid content and metal iron chelating activity was highest in A. cepa bulb, while lowest values were obtained in A. fistulosum and A. cepa bulb peel respectively. The results suggest that the A. cepa bulb peel, A. cepa bulb and A. fistulosum extracts can be used as sources of natural antioxidants. However, A. cepa bulb peel may be the most potent

Subchronic toxicity and behavioural effects of Glycine max (L.) oil emulsion in male rats

The oil of Glycine max commonly known as soybean oil has over the decades grown popularity for its low cholesterol hence its use within the household and commercially for food production has grossly increased. This study was aimed to determine the effects of long term consumption of soybean oil toxicologically and behaviourally.Male albino rats were administered with the vehicle, 5 and 10% oil emulsion for 30 days orally. The rats were subjected to behavioural tests such as novelty-induced behaviour (NIB), learning and memory tests and food intake measurement weekly. At the end of 30 days, rats were anesthetized and carefully dissected and blood sample was taken and analyzed haematogically and biochemically. The liver sample was also taken for biochemical analysis. Histopathological examinations were carried out on the brain, spleen, liver, kidney, lungs and testis samples.The results showed that oral administration of oil caused an increase in food intake, significant effect on NIB but had no effect on learning and memory. There was a significant (p<0.05) reduction in the level of both haemoglobin and PCV in the grouped administered with high dose. Biochemical analysis revealed a significant (p<0.05) increase in triglyceride, ALT, AST levels, with no effect on cholesterol. Histopathological analysis revealed no significant effects on the essential organs tested when compared with the vehicle treated rats.This study conclusively showed that soybean oil has central excitatory effects and there is need for caution when used for a long period since it has significant effects on biochemical parameters

Subchronic toxicity and behavioural effects of Glycine max (L.) oil emulsion in male rats

The oil of Glycine max commonly known as soybean oil has over the decades grown popularity for its low cholesterol hence its use within the household and commercially for food production has grossly increased. This study was aimed to determine the effects of long term consumption of soybean oil toxicologically and behaviourally.Male albino rats were administered with the vehicle, 5 and 10% oil emulsion for 30 days orally. The rats were subjected to behavioural tests such as novelty-induced behaviour (NIB), learning and memory tests and food intake measurement weekly. At the end of 30 days, rats were anesthetized and carefully dissected and blood sample was taken and analyzed haematogically and biochemically. The liver sample was also taken for biochemical analysis. Histopathological examinations were carried out on the brain, spleen, liver, kidney, lungs and testis samples.The results showed that oral administration of oil caused an increase in food intake, significant effect on NIB but had no effect on learning and memory. There was a significant (p<0.05) reduction in the level of both haemoglobin and PCV in the grouped administered with high dose. Biochemical analysis revealed a significant (p<0.05) increase in triglyceride, ALT, AST levels, with no effect on cholesterol. Histopathological analysis revealed no significant effects on the essential organs tested when compared with the vehicle treated rats.This study conclusively showed that soybean oil has central excitatory effects and there is need for caution when used for a long period since it has significant effects on biochemical parameters

Assessment of the Effects of Graded Doses of Polyphenolic-Rich Fraction of Garcinia kola Seeds on Pituitary–Testicular Axis of Male Wistar Rats

This study evaluated the ameliorative and prophylactic effects of 2 different doses of polyphenolic-rich fraction of Garcinia kola (PPRFGk) seeds on the histology and hormones of pituitary–testicular axis of male Wistar rats. Thirty-five male Wistar rats (150- 200 g) were divided into 7 groups of 5 rats each. Groups I and II were given distilled water (0.5 mL/day) for 8 days followed by propylene glycol (0.2 mL/d) and 600 mg/kg of PPRFGk, respectively, for 21 days. Group III received sodium arsenate (8 days), left untreated for 21 days. Groups IV and V received sodium arsenate (20 mg/kg) for 8 days followed by PPRFGk (300 and 600 mg/kg, respectively) for 21 days. Groups VI and VII received PPRFGk (300 and 600 mg/kg, respectively) for 21 days followed by sodium arsenate (20 mg/kg) for 8 days. Rats were killed by cervical dislocation 24 hours after the last dose and their blood collected through cardiac puncture. Blood sera were assayed for the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone using immunoassay techniques. Histology of the pituitary gland and testes was carried out. A significant reduction was observed in the concentration of FSH in groups IV, V, VI, and VII in comparison with groups I and II. The concentrations of both LH and testosterone showed significant decreases in groups IV, V, VI, and VII in comparison with group I. Group III presented with the lowest serum hormonal concentrations. Photomicrographs of the pituitary gland revealed greatly reduced basophils in group III and mildly reduced basophils in groups IV, VI, and VII in comparison with groups I and II. Group V revealed hypercellularized and distorted basophils. Photomicrographs of the testes showed detachment of the seminiferous tubules from the basement membrane and disruption of the interstitial space which was worse in group III, moderate in groups V and VI, and mild in group VII. In conclusion, PPRFGk effected a dose-dependent reversal and prevention of the perturbations caused by arsenate in rats

Comparative evaluation of antioxidant properties of methanol extracts of allium cepa bulb, allium cepa bulb peels and allium fistulosum

Medicinal plants have protective effects against many physiological diseases because of their phytochemical components which are better antioxidants. This study was aimed at comparing the in vitro antioxidant activity, phenolic and flavonoid content of the methanol extracts of Allium cepa bulb, Allium cepa bulb peel and Allium fistulosum. The antioxidant activity was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), iron chelating activity and molybdate ion reduction assays. The total flavonoid and total phenolic content (TPC) were carried out using aluminium chloride and Folin-Ciocalteu assay respectively. The results showed that A. cepa bulb peel has the highest phenolic content and the antioxidant activity while the A. fistulosum showed the least. Furthermore, the total flavonoid content and metal iron chelating activity was highest in A. cepa bulb, while lowest values were obtained in A. fistulosum and A. cepa bulb peel respectively. The results suggest that the A. cepa bulb peel, A. cepa bulb and A. fistulosum extracts can be used as sources of natural antioxidants. However, A. cepa bulb peel may be the most potent

Assessment of the Effects of Graded Doses of Polyphenolic-Rich Fraction of Seeds on Pituitary–Testicular Axis of Male Wistar Rats

This study evaluated the ameliorative and prophylactic effects of 2 different doses of polyphenolic-rich fraction of Garcinia kola (PPRF Gk ) seeds on the histology and hormones of pituitary–testicular axis of male Wistar rats. Thirty-five male Wistar rats (150-200 g) were divided into 7 groups of 5 rats each. Groups I and II were given distilled water (0.5 mL/day) for 8 days followed by propylene glycol (0.2 mL/d) and 600 mg/kg of PPRF Gk , respectively, for 21 days. Group III received sodium arsenate (8 days), left untreated for 21 days. Groups IV and V received sodium arsenate (20 mg/kg) for 8 days followed by PPRF Gk (300 and 600 mg/kg, respectively) for 21 days. Groups VI and VII received PPRF Gk (300 and 600 mg/kg, respectively) for 21 days followed by sodium arsenate (20 mg/kg) for 8 days. Rats were killed by cervical dislocation 24 hours after the last dose and their blood collected through cardiac puncture. Blood sera were assayed for the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone using immunoassay techniques. Histology of the pituitary gland and testes was carried out. A significant reduction was observed in the concentration of FSH in groups IV, V, VI, and VII in comparison with groups I and II. The concentrations of both LH and testosterone showed significant decreases in groups IV, V, VI, and VII in comparison with group I. Group III presented with the lowest serum hormonal concentrations. Photomicrographs of the pituitary gland revealed greatly reduced basophils in group III and mildly reduced basophils in groups IV, VI, and VII in comparison with groups I and II. Group V revealed hypercellularized and distorted basophils. Photomicrographs of the testes showed detachment of the seminiferous tubules from the basement membrane and disruption of the interstitial space which was worse in group III, moderate in groups V and VI, and mild in group VII. In conclusion, PPRF Gk effected a dose-dependent reversal and prevention of the perturbations caused by arsenate in rats