The leaves of Dorstenia mannii are used in traditional medicine in Cameroon and other African cou... more The leaves of Dorstenia mannii are used in traditional medicine in Cameroon and other African countries for the treatment of infectious diseases like malaria, skin rashes and stomach disorders. To substantiate this folkloric claim, the crude methanol extract and fractions from the leaves of D. mannii were investigated for their antifungal activity. The crude methanol extract was prepared from powdered dried leaves of the D. mannii. A portion was subjected to flash liquid chromatography on silica gel to afford test fractions. All test samples were screened for major groups of phytochemicals.Test samples and nystatin (reference) were evaluated for antifungal activity on ten yeasts using agar disc diffusion and broth microdilution methods. The qualitative analysis of crude methanol extract and fractions of D. mannii leaves revealed the presence of flavonoids, phenols, steroids and cardiac glycosides. In agar disc diffusion assay, seven of the ten pathogenic fungal strains were sensitiv...
Asian Journal of Research in Medical and Pharmaceutical Sciences, 2020
Herbal plants are very important in traditional community use and enrich our plant biodiversity a... more Herbal plants are very important in traditional community use and enrich our plant biodiversity and conservation. Natural products are vital substances of traditional knowledge systems in complementary and alternative medicine, nutraceutical, food supplements, and pharmaceutical bioactive metabolites of new chemical entities. Bioactive secondary metabolites from herbal plants of different forms are main sources and provide major opportunities for drug active pharmaceuticals due to the diverse flora and fauna biodiversity that produces the necessary available chemical diversity. There has been an increasing popularity in phytochemical research within the high through put (HTS) screening programs in search of lead. Phytochemicals of herbal extracts for traditional uses contain various types of bioactive metabolites of pharmaceutical and pharmacotherapeutic nature, and many phytomedicines for different therapeutic areas have been derived from herbal products. This paper is aimed at giv...
Toxicological Survey of African Medicinal Plants, 2014
Medicinal plants are used worldwide as an alternative and/or a complementary medicine. Studies on... more Medicinal plants are used worldwide as an alternative and/or a complementary medicine. Studies on these medicinal plants including pharmacological and toxicological evaluations are essential for drug research and development. The main types of toxicological evaluations include: acute toxicity, subacute toxicity, subchronic toxicity, and chronic toxicity studies. Medicinal plants also can be poisonous, affecting the entire spectrum of organ systems, with some plants containing several toxic principles that affect different systems. Toxic principles can be found in different parts of medicinal plants: leaves, fruits, flowers, roots, and stem bark. In evaluating the acute toxicity or subacute toxicity of medicinal plants, any animal species can be used, though rodents are used most often. Many African plants have undergone toxicity screening in the past three decades. In this chapter, we review more than 50 plants used in African Traditional Medicine (ATM) for several purposes. The criteria of classification their toxicity profile also are summarized. It appears that, though most of the plants in ATM are safe, numbers of them are potentially toxic and caution should be taken when they are used for therapeutic purposes. Some of these plants include Ocimum gratissimum, Pteleopsis hylodendron, Annona senegalensis, Syzigium aromaticum, Murraya koenigii, Sacoglottis gabonensis, and Spathodea campanulata.
International Journal of Biological and Chemical Sciences, 2020
Typhoid fever is an infectious disease that has been a public health concern for millennia. The u... more Typhoid fever is an infectious disease that has been a public health concern for millennia. The use of herbal preparations is getting popularity, with an estimated 80% of the world’s population still depending on it for the management of various diseases including typhoid fever. However, data concerning their quality, safety and efficacy is not readily available. Our aim was to determine the in vitro efficacy of some commercially available herbal preparations used in the treatment of typhoid fever in Bamenda Municipality. Five herbal preparations indicated for the treatment of typhoid fever (coded P1 to P5) were bought from various outlets of the herbal producers and serial dilutions made and screened for their activities against clinical isolates of Salmonella Typhi and Salmonella Paratyphi using the agar well diffusion and dilution methods. The bacterial growth inhibition zone diameters of the herbal preparations were measured with a transparent ruler and compared with those of so...
Aim: This study describes the activity-guided isolation of antimicrobial and antioxidant agents f... more Aim: This study describes the activity-guided isolation of antimicrobial and antioxidant agents from Trilepisium madagascariense stem bark. Methods: The methanol crude extract of T. madagascariense was partitioned sequentially into n-hexane, ethyl acetate, n-butanol and the residual aqueous fractions. The ethyl acetate fraction was subjected to column chromatography and the structures of isolated compounds were elucidated using GC-MS and/or NMR data by comparing with those reported in the literature. Antimicrobial activity was assayed by agar well diffusion and broth microdilution techniques on 8 bacteria and 10 yeasts. The antioxidant activity was determined by DPPH radical scavenging method. Results: The bioassay-guided fractionation of the crude methanol extract of T. madagascariense afforded two known compounds [vanillic acid (1) and isoliquiritigenin (2)] and two mixtures of fatty acids (n-hexane fraction and first column fraction of ethyl acetate fraction, F1). The fractionation of the crude methanol extract enhanced the antimicrobial activity. Compound 2 was generally more active than compound , 1. For all the tested samples, the most sensitive microbes were Enterococcus faecalis ATCC 10541 (MIC range of 60-780 μg/ml) for bacteria and Candida guillermondi (MIC range of 0.01-190 μg/ml) for yeasts. The DPPH radical scavenging activity (RSa) of compound , 2 (RSa 50 = 28.73 μg/ml) was comparable to that of the crude methanol extract (RSa 50 = 29.92 μg/ml). Conclusion: The antimicrobial activities and the antioxidant properties of the methanol crude extract, fractions and compounds 1 and , 2 from the stem bark of T. madagascariense are being reported for the first time. These results may justify the traditional use of this plant for the treatment of gastrointestinal disorders.
Background: The leaves of Cupressus lusitanica Mill. are used in the western highlands of Cameroo... more Background: The leaves of Cupressus lusitanica Mill. are used in the western highlands of Cameroon for their medicinal property. Methods: The leaves of this species were collected in the West Region of Cameroon in August 2010 and subjected to hydrodistillation to obtain the essential oil. The oil was fractionated using adsorption column chromatography. The chemical composition of this oil and its fractions was analysed by gas chromatography-mass spectrometry (GC-MS). The essential oil and fractions were tested for antimicrobial activity against eight bacterial species and six species of Candida by the agar diffusion method. Macrodilution method was used to determine the minimum inhibition concentrations (MICs) and minimum bactericidal and/or fungicidal concentrations (MBCs and MFCs). The toxicity profile of the oil was studied using Swiss mice and Wistar albino rats. Results: Forty-nine compounds were identified in the essential oil. The main components were germacrene D (18.5%), epi-zonarene (8.2%), cis-calamenene (8.2%), terpinen-4-ol (6.3%), linalool (6.0%) and umbellulone (6.0%). Enterococcus faecalis, Proteus mirabilis and Candida albicans were most susceptible to the oil (MICs of 1.25 and 0.16% for bacteria and fungi respectively). The estimated oral LD 50 was 6.33 g/kg. There was an increase in sera ALT and AST activities while the blood cells and protein levels decreased in treated animals. Conclusion: The results obtained from this study support the ethnomedicinal use of C. lusitanica leaf oil in the treatment of whooping cough and skin infections though it should be used with care. This plant oil could be useful in the standardisation of phytomedicine.
Emilia coccinea (Sims) G. Don is reported to possess a number of medicinal properties including a... more Emilia coccinea (Sims) G. Don is reported to possess a number of medicinal properties including antidiarrhoeal and antimicrobial activities. The antidiarrhoeal effects of both methanol and aqueous extracts of the leaves of Emilia coccinea were studied in rats against castor oil-induced diarrhoea at the doses of 200, 400 and 600 mg/kg body weight. The methanol extract, and to a lesser extent the aqueous extract, significantly prolonged the time for diarrhoeal induction; it reduced the frequency of diarrhoea episodes and decreased the propulsion of charcoal meal through the gastrointestinal tract in a dose dependent manner. The aqueous extract did not have any antimicrobial activity at the tested concentration (5 mg/ml), but the methanol extract was most active on Escherichia coli. These results may support the fact that this plant is used traditionally to cure diarrhoea.
Background The aim of this study was to evaluate the antimicrobial and antioxidant activities of ... more Background The aim of this study was to evaluate the antimicrobial and antioxidant activities of the methanol extract, fractions and isolated compounds from Entada abyssinica stem bark, plant used traditionally against gastrointestinal infections. Methods The methanol extract of E. abyssinica stem bark was pre-dissolved in a mixture of methanol and water, and then partitioned between n-hexane, ethyl acetate and n-butanol. The ethyl acetate portion was fractionated by column chromatography and the structures of isolated compounds elucidated by analysis of spectroscopic data and comparison with literature data. Antimicrobial activity was assayed by broth microdilution techniques on bacteria and yeasts. The antioxidant activity was determined by DPPH radical scavenging method. Results Four known compounds [(5S,6R,8aR)-5-(carboxymethyl)-3,4,4a,5,6,7,8,8a-octahydro-5,6,8a-trimethylnaphthalenecarboxylic acid (1), methyl 3,4,5-trihydroxybenzoate (2), benzene-1,2,3-triol (3) and 2,3-dihydro...
International Journal of Biological and Chemical Sciences, Apr 24, 2017
Though much has been documented on the biological activity of honey, no scientific report was see... more Though much has been documented on the biological activity of honey, no scientific report was seen on the antibacterial activity of honey from Oku, Mbengwi and Ngaoundéré in Cameroon. Our aim was to study the in vitro antibacterial activity of honey produced from these places against clinical isolates. Honey samples were tested for antibacterial activity at concentrations from 100 to 20% volume per volume (v/v) against clinical bacterial isolates using agar well diffusion method. MICs and MBCs of honey samples (49.02 to 1.53% v/v) were determined using broth and agar media respectively. Ciprofloxacin was used as reference substance (120 to 0.5 µg/ml). Honey pH was measured using CYBOW11 test strips. Data were analysed with the help of statistical package for social sciences (SPSS), version 19. These honey samples inhibited the studied bacterial growth at concentrations ≥ 40% with S. aureus and E. coli being more susceptible. Antibacterial activities at concentrations > 60% were comparable to that of the reference drug at p=0.05. The MICs and MBCs ranged from 12.25 to 49.02%. The pH of honeys was estimated to be 5. Oku, Mbengwi and Ngaoundéré honey samples showed antibacterial activity against some bacteria known to cause infectious diseases in humans.
International Journal of Basic & Clinical Pharmacology
Background: Due to paucity of studies on the prevalence and pattern of self medication among Came... more Background: Due to paucity of studies on the prevalence and pattern of self medication among Cameroonians and particularly dwellers of Bamenda City, in this research was undertaken to study the practice of self-drug administration among adult out patients at the Regional Hospital Bamenda; identify potential factors influencing self-medication practices; sources of drugs and/or information about medications and finally the reasons for self-drug administration.Methods: Participants (200) of age 18 years and above who came for external consultation during the study period were sampled conveniently after giving their consent. They were administered questionnaires on self-medication practices. Data was analyzed using SPSS version 19.0.Results: The prevalence of self-medication in this study was 86.50% (173/200). The females were more involved in the practice of self-medication (88.18%) than males (85.54%). Participants from deferent occupations had used various classes of drugs through s...
The leaves of Dorstenia mannii are used in traditional medicine in Cameroon and other African cou... more The leaves of Dorstenia mannii are used in traditional medicine in Cameroon and other African countries for the treatment of infectious diseases like malaria, skin rashes and stomach disorders. To substantiate this folkloric claim, the crude methanol extract and fractions from the leaves of D. mannii were investigated for their antifungal activity. The crude methanol extract was prepared from powdered dried leaves of the D. mannii. A portion was subjected to flash liquid chromatography on silica gel to afford test fractions. All test samples were screened for major groups of phytochemicals.Test samples and nystatin (reference) were evaluated for antifungal activity on ten yeasts using agar disc diffusion and broth microdilution methods. The qualitative analysis of crude methanol extract and fractions of D. mannii leaves revealed the presence of flavonoids, phenols, steroids and cardiac glycosides. In agar disc diffusion assay, seven of the ten pathogenic fungal strains were sensitiv...
Asian Journal of Research in Medical and Pharmaceutical Sciences, 2020
Herbal plants are very important in traditional community use and enrich our plant biodiversity a... more Herbal plants are very important in traditional community use and enrich our plant biodiversity and conservation. Natural products are vital substances of traditional knowledge systems in complementary and alternative medicine, nutraceutical, food supplements, and pharmaceutical bioactive metabolites of new chemical entities. Bioactive secondary metabolites from herbal plants of different forms are main sources and provide major opportunities for drug active pharmaceuticals due to the diverse flora and fauna biodiversity that produces the necessary available chemical diversity. There has been an increasing popularity in phytochemical research within the high through put (HTS) screening programs in search of lead. Phytochemicals of herbal extracts for traditional uses contain various types of bioactive metabolites of pharmaceutical and pharmacotherapeutic nature, and many phytomedicines for different therapeutic areas have been derived from herbal products. This paper is aimed at giv...
Toxicological Survey of African Medicinal Plants, 2014
Medicinal plants are used worldwide as an alternative and/or a complementary medicine. Studies on... more Medicinal plants are used worldwide as an alternative and/or a complementary medicine. Studies on these medicinal plants including pharmacological and toxicological evaluations are essential for drug research and development. The main types of toxicological evaluations include: acute toxicity, subacute toxicity, subchronic toxicity, and chronic toxicity studies. Medicinal plants also can be poisonous, affecting the entire spectrum of organ systems, with some plants containing several toxic principles that affect different systems. Toxic principles can be found in different parts of medicinal plants: leaves, fruits, flowers, roots, and stem bark. In evaluating the acute toxicity or subacute toxicity of medicinal plants, any animal species can be used, though rodents are used most often. Many African plants have undergone toxicity screening in the past three decades. In this chapter, we review more than 50 plants used in African Traditional Medicine (ATM) for several purposes. The criteria of classification their toxicity profile also are summarized. It appears that, though most of the plants in ATM are safe, numbers of them are potentially toxic and caution should be taken when they are used for therapeutic purposes. Some of these plants include Ocimum gratissimum, Pteleopsis hylodendron, Annona senegalensis, Syzigium aromaticum, Murraya koenigii, Sacoglottis gabonensis, and Spathodea campanulata.
International Journal of Biological and Chemical Sciences, 2020
Typhoid fever is an infectious disease that has been a public health concern for millennia. The u... more Typhoid fever is an infectious disease that has been a public health concern for millennia. The use of herbal preparations is getting popularity, with an estimated 80% of the world’s population still depending on it for the management of various diseases including typhoid fever. However, data concerning their quality, safety and efficacy is not readily available. Our aim was to determine the in vitro efficacy of some commercially available herbal preparations used in the treatment of typhoid fever in Bamenda Municipality. Five herbal preparations indicated for the treatment of typhoid fever (coded P1 to P5) were bought from various outlets of the herbal producers and serial dilutions made and screened for their activities against clinical isolates of Salmonella Typhi and Salmonella Paratyphi using the agar well diffusion and dilution methods. The bacterial growth inhibition zone diameters of the herbal preparations were measured with a transparent ruler and compared with those of so...
Aim: This study describes the activity-guided isolation of antimicrobial and antioxidant agents f... more Aim: This study describes the activity-guided isolation of antimicrobial and antioxidant agents from Trilepisium madagascariense stem bark. Methods: The methanol crude extract of T. madagascariense was partitioned sequentially into n-hexane, ethyl acetate, n-butanol and the residual aqueous fractions. The ethyl acetate fraction was subjected to column chromatography and the structures of isolated compounds were elucidated using GC-MS and/or NMR data by comparing with those reported in the literature. Antimicrobial activity was assayed by agar well diffusion and broth microdilution techniques on 8 bacteria and 10 yeasts. The antioxidant activity was determined by DPPH radical scavenging method. Results: The bioassay-guided fractionation of the crude methanol extract of T. madagascariense afforded two known compounds [vanillic acid (1) and isoliquiritigenin (2)] and two mixtures of fatty acids (n-hexane fraction and first column fraction of ethyl acetate fraction, F1). The fractionation of the crude methanol extract enhanced the antimicrobial activity. Compound 2 was generally more active than compound , 1. For all the tested samples, the most sensitive microbes were Enterococcus faecalis ATCC 10541 (MIC range of 60-780 μg/ml) for bacteria and Candida guillermondi (MIC range of 0.01-190 μg/ml) for yeasts. The DPPH radical scavenging activity (RSa) of compound , 2 (RSa 50 = 28.73 μg/ml) was comparable to that of the crude methanol extract (RSa 50 = 29.92 μg/ml). Conclusion: The antimicrobial activities and the antioxidant properties of the methanol crude extract, fractions and compounds 1 and , 2 from the stem bark of T. madagascariense are being reported for the first time. These results may justify the traditional use of this plant for the treatment of gastrointestinal disorders.
Background: The leaves of Cupressus lusitanica Mill. are used in the western highlands of Cameroo... more Background: The leaves of Cupressus lusitanica Mill. are used in the western highlands of Cameroon for their medicinal property. Methods: The leaves of this species were collected in the West Region of Cameroon in August 2010 and subjected to hydrodistillation to obtain the essential oil. The oil was fractionated using adsorption column chromatography. The chemical composition of this oil and its fractions was analysed by gas chromatography-mass spectrometry (GC-MS). The essential oil and fractions were tested for antimicrobial activity against eight bacterial species and six species of Candida by the agar diffusion method. Macrodilution method was used to determine the minimum inhibition concentrations (MICs) and minimum bactericidal and/or fungicidal concentrations (MBCs and MFCs). The toxicity profile of the oil was studied using Swiss mice and Wistar albino rats. Results: Forty-nine compounds were identified in the essential oil. The main components were germacrene D (18.5%), epi-zonarene (8.2%), cis-calamenene (8.2%), terpinen-4-ol (6.3%), linalool (6.0%) and umbellulone (6.0%). Enterococcus faecalis, Proteus mirabilis and Candida albicans were most susceptible to the oil (MICs of 1.25 and 0.16% for bacteria and fungi respectively). The estimated oral LD 50 was 6.33 g/kg. There was an increase in sera ALT and AST activities while the blood cells and protein levels decreased in treated animals. Conclusion: The results obtained from this study support the ethnomedicinal use of C. lusitanica leaf oil in the treatment of whooping cough and skin infections though it should be used with care. This plant oil could be useful in the standardisation of phytomedicine.
Emilia coccinea (Sims) G. Don is reported to possess a number of medicinal properties including a... more Emilia coccinea (Sims) G. Don is reported to possess a number of medicinal properties including antidiarrhoeal and antimicrobial activities. The antidiarrhoeal effects of both methanol and aqueous extracts of the leaves of Emilia coccinea were studied in rats against castor oil-induced diarrhoea at the doses of 200, 400 and 600 mg/kg body weight. The methanol extract, and to a lesser extent the aqueous extract, significantly prolonged the time for diarrhoeal induction; it reduced the frequency of diarrhoea episodes and decreased the propulsion of charcoal meal through the gastrointestinal tract in a dose dependent manner. The aqueous extract did not have any antimicrobial activity at the tested concentration (5 mg/ml), but the methanol extract was most active on Escherichia coli. These results may support the fact that this plant is used traditionally to cure diarrhoea.
Background The aim of this study was to evaluate the antimicrobial and antioxidant activities of ... more Background The aim of this study was to evaluate the antimicrobial and antioxidant activities of the methanol extract, fractions and isolated compounds from Entada abyssinica stem bark, plant used traditionally against gastrointestinal infections. Methods The methanol extract of E. abyssinica stem bark was pre-dissolved in a mixture of methanol and water, and then partitioned between n-hexane, ethyl acetate and n-butanol. The ethyl acetate portion was fractionated by column chromatography and the structures of isolated compounds elucidated by analysis of spectroscopic data and comparison with literature data. Antimicrobial activity was assayed by broth microdilution techniques on bacteria and yeasts. The antioxidant activity was determined by DPPH radical scavenging method. Results Four known compounds [(5S,6R,8aR)-5-(carboxymethyl)-3,4,4a,5,6,7,8,8a-octahydro-5,6,8a-trimethylnaphthalenecarboxylic acid (1), methyl 3,4,5-trihydroxybenzoate (2), benzene-1,2,3-triol (3) and 2,3-dihydro...
International Journal of Biological and Chemical Sciences, Apr 24, 2017
Though much has been documented on the biological activity of honey, no scientific report was see... more Though much has been documented on the biological activity of honey, no scientific report was seen on the antibacterial activity of honey from Oku, Mbengwi and Ngaoundéré in Cameroon. Our aim was to study the in vitro antibacterial activity of honey produced from these places against clinical isolates. Honey samples were tested for antibacterial activity at concentrations from 100 to 20% volume per volume (v/v) against clinical bacterial isolates using agar well diffusion method. MICs and MBCs of honey samples (49.02 to 1.53% v/v) were determined using broth and agar media respectively. Ciprofloxacin was used as reference substance (120 to 0.5 µg/ml). Honey pH was measured using CYBOW11 test strips. Data were analysed with the help of statistical package for social sciences (SPSS), version 19. These honey samples inhibited the studied bacterial growth at concentrations ≥ 40% with S. aureus and E. coli being more susceptible. Antibacterial activities at concentrations > 60% were comparable to that of the reference drug at p=0.05. The MICs and MBCs ranged from 12.25 to 49.02%. The pH of honeys was estimated to be 5. Oku, Mbengwi and Ngaoundéré honey samples showed antibacterial activity against some bacteria known to cause infectious diseases in humans.
International Journal of Basic & Clinical Pharmacology
Background: Due to paucity of studies on the prevalence and pattern of self medication among Came... more Background: Due to paucity of studies on the prevalence and pattern of self medication among Cameroonians and particularly dwellers of Bamenda City, in this research was undertaken to study the practice of self-drug administration among adult out patients at the Regional Hospital Bamenda; identify potential factors influencing self-medication practices; sources of drugs and/or information about medications and finally the reasons for self-drug administration.Methods: Participants (200) of age 18 years and above who came for external consultation during the study period were sampled conveniently after giving their consent. They were administered questionnaires on self-medication practices. Data was analyzed using SPSS version 19.0.Results: The prevalence of self-medication in this study was 86.50% (173/200). The females were more involved in the practice of self-medication (88.18%) than males (85.54%). Participants from deferent occupations had used various classes of drugs through s...
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