Charles O. Okoli

University of Nigeria | UNN · Department of Pharmacology and Toxicology

Introduction: Caralluma dalzielii N E Brown (Asclepiadiaceae) is a cactus-like shaped plant that grows mainly in the Sahel savannah region of Africa. Its decoction is traditionally used to promote fertility. The aim of the study was to determine the ovulation inducing effect of extract and various solvent fractions of Caralluma dalzielii. Materia...

Introduction Phyllanthus muellerianus (Kuntze) Exell. (Phyllanthaceae) is an evergreen monoecious shrub widely distributed in tropical and subtropical regions of the world. In South-eastern Nigeria, preparations from the leaf is used in treating pain, epilepsy, convulsion, and other central nervous system disorders. This study was aimed to evaluate...

Caralluma dalzielii N. E. Brown belonging to family Asclepiadaceae, is a popular cactus-shaped plant native to East Africa. The aerial parts are used traditionally for treating various diseases including infertility. The present study evaluated the effects of the aqueous extract of the aerial parts of Caralluma dalzielii (AECD) on reproductive perf...

Introduction Caralluma dalzielii N. E. Brown (family: Asclepiadaceae), is a popular cactus‐shaped plant native to East Africa. Its aerial parts are used traditionally for treating infertility, obesity and diabetes. The aim of the study was to evaluate the effects of aqueous extract of the aerial parts of Caralluma dalzielii (AECD) on reproductive f...

Caralluma dalzielii N. E. Brown (Asclepiadaceae) is a cactus-like shaped shrub widely used in traditional medicine for the treatment of rheumatoid arthritis, diabetes, infertility and impotence. The present study evaluated the potential toxicity of aqueous extract of aerial parts of Caralluma dalzielii (AECD) through acute and sub-acute oral admini...

Background: Azadiradita indica seed has been used in traditional system of medicine. It is known to be natural medicine with many benefits. Toxicological studies have reported that toxic effects may be related to the complex mixtures of active constituents and other chemicals which increase the risk of adverse reactions. Objective: The purpose of t...

Azadirachta indica seed extract has been shown to have antihyperglycemic and antihyperlipidemic effect as per earlier report of traditional medicine used by native people of Africa origin. In the present study, antihyperglycemic and antihyperlipidemic effect of Azadirachta Indica (family, Meliaceae) seed was evaluated in adult albino rat. Methanol...

Objective: Schwenckia americana L. (Solanaceae) is employed as a decoction of either the leaves, roots or the whole plant in the treatment of diarrhoea in most West African countries. Using a comparative study approach, the antidiarrheal potentials of its aerial part and root extracts were evaluated to substantiate its local use in diarrhoea manage...

Background: Azadiradita indica seed has been used in traditional system of medicine. It is known to be natural medicine with many benefits. Toxicological studies have reported that toxic effects may be related to the complex mixtures of active constituents and other chemicals which increase the risk of adverse reactions. Objective: The purpose of t...

Objective: In southeastern Nigeria, Nauclea diderrichii (De Wild) Merr is used in the treatment of a wide range of ailments including diabetes mellitus (DM). This study evaluates the antidiabetic activity and toxicological profile of the methanol-dichloromethane root bark extract of N. diderrichii in normoglycemic and alloxan-induced diabetic model...

Aim Ocimum basilicum L (Lamiaceae) is used as a traditional remedy for different ailments, including diabetes mellitus. This study investigated the antidiabetic effects of an extract of aerial parts of O. basilicum. Methods Antihyperglycemic effect of the extract was determined by its effects on α-amylase and α-glucosidase in vitro, while antidiab...

Background: New antimalarial drugs are required to fight resistant parasites and plantderived natural products are a robust source for identifying active lead compounds. Stachytarpheta cayennensis (Verbenaceae) is traditionally used in west and central Africa as malaria remedy. Objective: This study was undertaken to evaluate antiplasmodial activit...

The study was aimed at investigating the antioxidant properties of lupeol isolated from the methanol leaf extract of Crateva adansonii. In order to assess the antioxidant effect of lupeol in vitro (1, 1-diphenyl-2-picrylhydrazyl radical (DPPH) spectrophotometric assay, Ferric reducing antioxidant power (FRAP) assay, Hydrogen peroxide scavenging ass...

Background: The fatty seed extract of Vitellaria paradoxa Kernel (Sapotaceae) commonly called “Shea butter”, is a popular remedy for arthritis in west Africa. This study investigated the knowledge, prevalence and pattern of use of Shea butter in clinically diagnosed arthritic patients as well as its effects on acute (topical and systemic) and chron...

Earlier studies in our laboratory demonstrated the anti-inflammatory activity of Buchholzia coriacea Engl. (Capparaceae) leaf extract, a herbal remedy used to treat disorders of inflammation. This study was undertaken to evaluate its anti-inflammatory mechanism(s). The effects of methanol leaf extract of B. coriacea (200 and 400 mg/kg) on vascular...

ABSTRACT The effects of the methanol extract (LHE), hexane (LHHF), ethylacetate (LHEF) and methanol (LHMF) fractions of leaf of Leptadenia hastata on acute and chronic inflammation were studied. Furthermore, the effects of LHE on acetic acid induced increase in vascular permeability, carrageenan induced leucocyte migration and membrane stability we...

The antiinflammatory activity of the methanol:methylene chloride extract of the aerial parts of Schwenckia americana L. (Solanaceae) (SAE) and its mechanisms were evaluated. Bioactivity-guided studies on SAE and its fractions was done using the egg albumin-induced rat paw edema as activity guide. Further screening for anti-inflammatory activity was...

The effect of methanol extract (ME), dichloromethane (DCMF), and methanol (MF) fractions of aerial parts of Phyllanthus niruri (Euphorbiacaeae) on acute and chronic inflammation were studied. An acute toxicity test in mice was used to establish an oral LD50 >5,000 mg.kg−1 for ME. The ME and fractions inhibited the development of topical edema in th...

The gastrointestinal and antibacterial properties of dichloromethane: Methanol extract (DVE) and fractions (DVHF, DVDF and DVMF) from Desmodium velutinum Willd. DC. (Fabaceae) leaves were investigated. The extract and fractions significantly (p<0.05) reduced normal defecation in rats (33- 100%) and significantly (p<0.05-0.001) protected rats agains...

The methanol-dichloromethane leaf extract (MDE) of Ocimum basilicum L. (Lamiaceae)was subjected to biological activity-guided studies using antihyperglycemic effect in alloxan diabetic rats as activity-guide. The hypoglycemic and oral glucose tolerance effects were also evaluated in normal rats. The results showed that the extract and the fractions...

Considering the current surge in the use of artemether-lumefantrine combination (AL), as a treatment regimen for malaria infection, this research elucidated its sub-acute and delayed toxicity profile. Adult albino wistar rats were randomly placed in 7 groups (n=8). Groups 1-3 received oral AL 14, 28 and 56 mg/kg and were used for the sub-acute toxi...

Root bark preparation of Annona senegalensis Pers. (Annonaceae) is used in Nigerian ethnomedicine for treatment of infectious diseases. Extraction of the A. senegalensis powdered root bark with methanol-methylene chloride (1 : 1) mixture yielded the methanol-methylene extract (MME) which was fractionated to obtain the ethyl acetate fraction (EF). T...

Problem statement: Iron is present in ferritin, the storage form of iron in the tissues; in the respiratory cytochrome enzymes; in hemoglobin of the blood and in the myoglobin of muscle Dihydroartemisinin (DHA) has been shown to interact with heme groups in vivo and in vitro. This study investigated the effects of 5 day and 7day oral dihydroartemis...

The methanol extract of Bridelia ferruginea Benth (Euphorbiaceae) stem bark obtained by 48 h cold maceration (BFME), was fractionated in a silica gel column to yield the petroleum ether (PF), dichloromethane (DF) and methanol (MF) fractions successively. The effects of the extract and fractions on bleeding, wound contraction and rate of epitheliali...

Apium graveveolens (Celery) an ancient vegetable spice consumed in both tropical and western world was investigated for its antioxidant properties. The ethanol extract of Apium graveolens gave 15.5% yield and the extract was used for lipid peroxidation scavenging tests. The acute toxicity of the ethanol extract of Apium graveolens was investigated...

CONTEXT/OBJECTIVES: The effects of methanol extract of aerial parts of Phyllanthus niruri L. (Euphorbiaceae), an antidiabetic herb, on glucose absorption and storage in diabetes were studied to elucidate the mechanisms of blood glucose lowering and glycemic control in diabetes. The effect of chronic oral administration of the extract on glycemic co...

The antiulcer and gastrointestinal effects of methanol stem bark extract (BFME) of Bridelia ferruginea Benth. (Euphorbiaceae) and its solvent fractions-dichloromethane (DCMF) and methanol (MF)-were studied using indomethacin- and ethanol-induced ulcers in rats, small intestinal transit of charcoal meal in mice, and the effects on acetylcholine-indu...

The neuropharmacological activities of methanol leaf extract (ME) of Annona senegalensis Pers (Annonaceae) and its bioactive fractions (MF and F 7) were studied in rodents using pentylenetetrazol (PTZ)-induced seizures, pentobarbitone-induced sleep, apomorphine-induced stereotypy, open field, elevated plus maze (EPM) and rotarod performance tests....

Phyllanthus niruri (Euphorbiaceae) is used folklorically for the treatment of diabetes, malaria, fever, diarrhea, liver disease, and urolithiasis. As an initial step toward isolating compounds effective against inflammation and pain, this study is aimed at providing scientific evidence for the anti-inflammatory, antinociceptive, and antipyretic pro...

The effects of the methanol extract of the stem bark of Prosopis africana (Guill., Perrott. and Rich.) Taubert (Fabaceae) on bleeding/clotting and coagulation time, excision and dead space wounds were studied in rats. Also, the extract was subjected to antibacterial, and acute toxicity and lethality (LD(50)) tests. The extract significantly (P<0.05...

Anticonvulsant and anxiolytic activities of leaf extracts and fraction of Ocimum gratissimum L. (Lamiaceae) were studied using seizures induced by pentylenetetrazol and open-field tests in mice. The results showed that the extracts and fraction increased the latency of tonic and tonic-clonic seizures and death and elicited 50% protection against mo...

Objective To investigate the antimicrobial activity of the methanol leaf extract (ME), n-hexane fraction (HF), ethylacetate fraction (EF) and methanol fraction (MF), of Stachytarpheta cayennensis C. Rich (verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions (HF, EF and MF) on acetylcholine (Ach) and his...

The antidiabetic activity of methanol leaves extract of Cajanus cajan (L.) Millsp. (Fabaceae) was studied in alloxan-diabetic and in oral glucose loaded rats. The acute toxicity and lethality (LD50) and the phytochemical analysis of the extract were also evaluated. The results showed that the extract (400 and 600 mg/kg) significantly (P<0.05) reduc...

The antidiabetic potentials of methanol extract (ME) of aerial parts of Phyllanthus niruri L (Euphorbiaceae) was evaluated in normal and alloxan diabetic rats. The results showed that ME significantly (P<0.05) reduced fasting blood sugar in a dose-related manner and suppressed the postprandial rise in blood glucose after a heavy glucose meal in nor...

Context/Objective: Artemisinin combina- tion therapy (ACT) is currently the recom- mended first line treatment for uncompli - cated malaria. However, with a plethora of ACTs currently available in Nigeria, it is pertinent to establish the efficacy of these drugs in clinical settings. This study aimed at evaluating the efficacy of the artesunate- am...

The anti-diarrheal effect of methanol extract (ME) of seeds of Monodora tenuifolia Benth(Annonaceae), a wildly growing orchid flowering tree whose seed is traditionally used as antidiarrhea remedy,was studied using rodent models of diarrhea, enteropooling and gastrointestinal motility induced by castor oil.Acute toxicity and lethality (LD50) and ph...

The anti-ulcer potentials of aqueous (AE) and methanol (ME) extracts of whole unripe Carica papaya fruit were evaluated using ethanol- and indomethacin-induced gastric ulcer models in rats. The effect of the extracts on small intestinal propulsion was also investigated. The extracts significantly reduced the ulcer index in both experimental models...

Problem statement: Phyllanthus niruri is widely used in many parts of the world to manage a wide range of diseases. As part of efforts to elucidate its pharmacological activities and hence medicinal potential, we studied the wound hea ling and antiulcer properties of extract of the aerial parts using experimentally-created wounds an d ulcers in rod...

Problem statement: The current surge in the use of Artemisinin based Combination Therapy (ACT) in the treatment of falciparium resis tant malaria in the tropics and the potentials of Dihydroartemisinin (DHA), a member of the artemisinin family, to produce toxic effect in the vital organs (such as the liver, heart, lungs, intestine, spleen kidney an...

The leaves of Vernonia amygdalina Del (Asteraceae) was processed into herbal tea using the black and green tea processing techniques. The green tea obtained was used as such while a portion of the black tea was flavored with O. basilicum or O. gratissimum. Methanol extracts of the flavored and unflavored herbal teas, obtained by cold maceration, we...

The oxytocic property of leaf extract of Spondias mombin. Linn. (Anacardiaceae) was evaluated in relation to its folkloric use by traditional birth attendants. The abortifacient effect of the methanol leaf extract (ME) obtained by cold maceration for 48 h, was evaluated in vivo. in pregnant mice and rats at different trimesters of pregnancy. The ef...

The aqueous leaf extract of Viscum album Stapf (Loranthaceae) given i.p. produced a dose-dependent fall in blood sugar. Doses of 200 mg/kg and 400 mg/kg body weight produced significant (p < 0.05) lowering of blood sugar in fasted normal white albino rats and alloxanized rabbits respectively. The fasting blood sugar, measured in milligram per 100ml...

The bronchospasmolytic constituent of leaves of Asystasia gangetica (L.) T. Anderson, sub-specie micrantha (Nees)Ensermu (Acanthaceae) was isolated by bio-activity-guided technique. The bronchospasmolytic effect of the fractions of the leafextract as well as the isolate AG-1 was evaluated using histamine-induced contraction of the guinea pig trache...

Afzelia africana Smith (Caesalpiniaceae) is a perennial tree which occurs in many parts of Africa where it is used as food and widely employed in traditional medicine practice. Acute toxicity studies in mice established an oral LD50 greater than 5,000 mg/kg for bark methanolic extract. The extract and fractions (5 and 10 mg/ear; 200 and 400 mg/kg)...

The immunomodulatory properties of kolaviron (KV), a mixture of three related biflavonoids of Garcinia kola Heckel (Clusiaceae), were investigated. The study was conducted using in vitro and in vivo immunocompetent and immunocompromised animal models. KV (250 and 500 mg/kg) produced a dose-dependent and significant (p < 0.05) inhibition of delayed-...

Acanthus montanus (Nees) T. Anderson (Acanthaceae) is a shrub widespread in Africa, the Balkans, Romania, Greece and Eastern Mediterranean. It is used in African traditional medicine for the treatment of urogenital infections, urethral pain, endometritis, urinary disease, cystitis, leucorrhoea, aches and pains. In southeastern Nigeria, the root is...

A methanol extract and fractions (pet ether and methanol) of Aframomum melegueta K. Schum (Zingiberacea) seeds were evaluated for anti-inflammatory activity. An acute toxicity test in mice was used to establish an i.p. LD50 of 2154 mg/kg for the methanol extract. The methanol extract and the pet ether fraction (oil) significantly (P < 0.05) inhibit...

The modulatory activity of methanolic seed extracts of Garcinia kola (ME) on Delayed-Type Hypersensitivity (DTH) response, primary and secondary humoral responses and on in vivo leucocytes mobilisation were evaluated. Acute toxicity test of the extract was also carried out. The ME at 250 and 500 mg kg^-1 body weight produced significant (...

The potentials of the leaves of the haemorrhage plant, Aspilia africana C. D Adams (Compositae) in wound care was evaluated using experimental models. A. africana, which is widespread in Africa, is used in traditional medicine to stop bleeding from wounds, clean the surfaces of sores, in the treatment of rheumatic pains, bee and scorpion stings and...

The anti-inflammatory activity of hexane leaf extract of Aspilia africana C.D. Adams (Compositae) was evaluated in rodents using the xylene-induced ear edema, egg albumin- and agar-induced paw edema, formaldehyde-induced arthritis, cotton pellet granuloma, gastric ulcerogenic, acetic acid-induced vascular permeability and dextran-induced in vivo le...

The anti-inflammatory and analgesic activities of extract of leaves of Vitex doniana Sweet (Verbenaceae) were investigated as well as the mechanisms of action. The extract significantly (P<0.05) inhibited the formation of paw edema induced by agar in rats and increased reaction latency to thermal pain in mice in a dose-dependent manner. The extract...

Analgesic activity of methanol leaf extract of C. scandens obtained by column chromatography and its graded solvent fractions, was evaluated in mice using acetic acid-induced abdominal writhing and formalin-induced paw licking. The extract and fractions significantly inhibited abdominal writhing and two phases of formalin-induced paw licking in mic...

The effect of extract and fractions of the root bark of Securidaca longipedunculata Fres (Polygalaceae) on acute inflammation was evaluated. Solvent extraction yielded the crude methanol extract (ME) while solvent–guided extraction yielded a petroleum ether fraction (PF) and methanol fraction (MF). The extract and fractions inhibited topical edema...

The mechanisms of the anti-inflammatory activity of the leaf extracts of Culcasia scandens P. Beauv were evaluated. The methanol leaf extract (CE) of C. scandens was subjected to bioactivity-guided separation to obtain fraction C as the most active anti-inflammatory fraction. Further activity-guided fractionation of fraction C led to the isolation...

This study was carried out to investigate the effect of concurrent oral administration of aqueous leaf extract of Azadirachta indica (Meliaceae) on the pharmacokinetic properties of chloroquine sulphate in experimental rabbits. The results indicated that concurrent administration of both agents resulted in a significant decrease in serum concentrat...

The leaf of Asystasia gangetica T. Adams (Acanthaceae) is used in many parts of Nigeria for the management of asthma. This study was aimed at investigating the anti-asthmatic property of hexane, ethylacetate, and methanol extracts of the leaves of Asystasia gangetica, obtained by successive sohxlet extraction. The results indicated that the extract...

As a result of the inherent problems associated with the current anti-inflammatory agents, there is continuous search especially from natural sources for alternative agents. A good number of plants are employed in the treatment of inflammatory disorders by natural healers. Some of these plants include Aloe vera, Consolida regalis, Chasmanthera depe...

Bacterial infections often co-exist with acute malarial attacks. The effect of combining arthemeter (a new antimalarial) with some commonly used 4-quinolones (ciprofloxacin, pefloxacin, norfloxacin and nalidixic acid) was investigated in-vitro with a view to providing data for the design of drug regimens for the treatment of such infections. While...

The effect of Garcinia kola seed extract (100 mg/kg) on the pharmacokinetic and antibacterial effects of ciprofloxacin hydrochloride (40 mg/kg) was studied. The results (mean +/- SEM) indicated that concurrent administration of both agents significantly (P < 0.05) decreased average serum concentration, peak serum concentration, and elimination rate...

The ethanolic root extract of Cissampelos mucronata was investigated for sedative activity. Phytochemical analysis indicated the presence of alkaloids: sterols/triterpenes, tannins, carbohydrates, glycosides, and flavonoids. Acute lethality test gave an LD50 of 282.84 mg/kg. The study of the effect of the extract on the behavioural pattern of mice...

Objective: To investigate the uterine smooth muscle relaxant property of the root extract of Cissampelos mucronata and relate it to its traditional use in the prevention of pre-term labour. Materials and methods: Phytochemical and pharmacological screenings were carried out using standard procedures. In addition to investigating the effects of the...

Diabetes is becoming a scourge of both developed and resource-poor countries. The disease seriously threatens the mere existence and economic survival of many resource-poor countries. The major question in the care of diabetes, especially Type 1 diabetes has to do with the availability and affordability of insulin. Insulin is a very expensive drug...

Aqueous stem bark extract of Pseudocedrela kotschyi, Harms (Meliaceae) was investigated for antiulcer activity. The extract neither contracted nor relaxed the isolated guinea pig ileum. It however, inhibited the contraction evoked by acetylcholine and histamine in a doserelated manner. Gastrointestinal motility in mice was significantly (p<0.05) in...

Objective: To investigate the claimed purgative property of aqueous leaf extract of Peninanthus longifolius. Materials and methods: Safety profile was evaluated using acute toxicity test (mice). Phytochemical constituents were determined using standard procedures. Effect of extract on the intestinal muscle was studied in isolated guinea pig ileum i...

To screen the anti-inflammatory potentials of a popular traditional antirheumatic herb, Culcasia scandens. The leaves of Culcasia scandens were collected, identified, dried, and reduced to coarse powder and extracted with methanol. The methanol extract was fractionated into seven fractions. The fractions were subjected to phytochemical analysis to...