Objective:To investigate the anti-inflammatory activity of the extract of Vernonia amygdalina (V.A).Methods:Inflammatory response was induced by topical application of croton oil dissolved in suitable vehicle on the r...Objective:To investigate the anti-inflammatory activity of the extract of Vernonia amygdalina (V.A).Methods:Inflammatory response was induced by topical application of croton oil dissolved in suitable vehicle on the rat ear.After 6 hrs,cutting out the ear quantitated the response.The cut ear was weighed and the increase in weight relative to control group was evaluated.Results:When co-applied with croton oil to the rat ear extract of V.A.produced a reduction in the inflammatory response when croton oil alone was applied to the rat ear.The extract produced(69.1 +2.0)%reduction of the inflammatory response produced by croton oil alone,lower than the reduction of the inflammatory response produced by acetyl salicylic acid[(71.1±2.0)%].Conclusions:This finding suggests that extract of V.A.exhibits antiinflammatory activity and may explain the usefulness of the leaves of this plant in the treatment of inflammatory disease conditions by traditional healers.展开更多
Vernonia amygdalina Del. is one of the leafy vegetables that can be used in an attempt to alleviate the problem of micronutrient malnutrition, prominent in tropical Africa. In order to ensure availability in non-growi...Vernonia amygdalina Del. is one of the leafy vegetables that can be used in an attempt to alleviate the problem of micronutrient malnutrition, prominent in tropical Africa. In order to ensure availability in non-growing areas or seasons, the vegetable needs to be preserved. Processing and preservation methods influence the nutrient content of vegetables. The present study was aimed at determining the effects of preservation on two different varieties of V. amygdalina (bitter) leaves (broad and small leaves). To this effect, evaluations were made on the chlorophyll content, phytochemicals, and antioxidant capacity of the two varieties of bitter leaf (V. amygdalina Del.) stored at 4℃ and –20℃ over a period of two weeks. Results showed a significant decrease in all parameters studied for both varieties at –20℃ except for the free radical reducing power (FRAP), DPPH radical scavenging activity (%RSA) and nitric oxide radical scavenging activity (%RSA) of V. amygdalina broad leaves where increase in scavenging activity was observed. Thus, it was concluded that to preserve the chlorophyll, phenol, total soluble proteins and reducing sugar levels, preservation at 4℃ is recommended. The present study finding would be useful during short-term preservation of bitter leaves for soup preparation and/or its aqueous extract for ethnomedicinal purposes, especially the small leaf variety.展开更多
Breast cancer is the second leading cause of cancer-related deaths of women in the United States. Fortunately, the mortality rate from breast cancer has decreased in recent years due to an increased emphasis on early ...Breast cancer is the second leading cause of cancer-related deaths of women in the United States. Fortunately, the mortality rate from breast cancer has decreased in recent years due to an increased emphasis on early detection and more effective treatments. Although great advancements have been made in the treatment and control of cancer progression, significant deficiencies and room for improvement remain. The central objective of this research was to further determine the in vitro mechanisms of Vernonia amygdalina (VA) leaf extracts as an anticancer candidate for the treatment of breast cancer. To achieve our objective, MCF-7 cells were treated with different concentrations of VA for 24 hand 48 h. Cell viability, live and dead cells were determined by the means of trypan blue exclusion test. Live and dead cells were further evaluated by propidium iodine (PI) assay using the Cellometer Vision. Cell apoptosis was measured by flow cytometry assessment using annexin V/PI kit. Data obtained from the trypan blue test demonstrated that VA treatment reduces cell viability in a concentration- and time-dependent manner. Result of the PI assay showed a gradual increase in the population of necrotic cells (fluorescence positive cells) in VA-treated cells compared to the control cells (fluorescence negative cells). Treatment of these cancer cells (MCF-7) for 48 h at concentrations ranging from 250 μg/mL to 1000 μg/mL caused early signs of apoptosis resulting from phosphatidylserine externalization as judged by annexin V assay. We observed a strong concentration-response relationship with regard to VA exposure and annexin V/PI positive cells. In summary, our finding demonstrates that VA-induced cytotoxicity and apoptosis in MCF-7 cells involve phosphatidylserine externalization accompanied by secondary necrotic cell death. With previous findings in our laboratory, the data generated in the present study confirms that VA is a valuable botanical therapeutic agent for the treatment of breast cancer.展开更多
The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and ...The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and 91% Al was sand cast at the Foundry Shop of the National Metallurgical Development Centre, Jos, Nigeria. The cast alloy was cut and machined to corrosion coupons and immersed into 0.5 M NaOH solution containing varying inhibitor concentrations (0.1%, 0.2%, 0.3%, 0.5% v/v) within a period of fifteen days. From the result, it was found that the adsorption of Vernonia amygdalina reduced the corrosion rate of this group of alloy in the alkaline medium. The inhibitive action of this plant extract was explained using inhibition efficiency and degree of surface coverage. The most suitable inhibitor concentration was found to be 0.5% with inhibition efficiency of 87%. The mechanism of inhibition is by physical adsorption and the adsorbed molecules of the inhibitor lies on the surface of the alloy blocking the active corrosion sites on the alloy, hence, giving the alloy a higher corrosion resistance in the studied environment.展开更多
In this work, adsorption and thermodynamics study of the inhibition of corrosion of mild steel in H2SO4 medium using Vernonia amygdalina was carried out. The inhibitive and adsorptive properties of ethanol extract of ...In this work, adsorption and thermodynamics study of the inhibition of corrosion of mild steel in H2SO4 medium using Vernonia amygdalina was carried out. The inhibitive and adsorptive properties of ethanol extract of Vernonia amygdalina for the corrosion of mild steel in 0.2 M H2SO4 solutions was investigated using weight loss technique. The result has proved that that the extract is a good inhibitor of corrosion of mild steel in H2SO4. The inhibition efficiencies ranged from 23.37 to 38.59% and from 22.45 to 35.78% at 303 and 323K respectively. The inhibition efficiency of the extract decreased as temperature and time of immersion increased but increased with increase in concentration of extract. The adsorption of the inhibitor on surface of mild steel was found to be exothermic, spontaneous and consistent with the mechanism of physical adsorption as the value for heat of adsorption ranged from -2.12 to -4.87KJ mol–1. The adsorption data fitted well to Langmuir, Temkin, Frumkin and Flory-Huggins adsorption isotherms.展开更多
Objective:Aim of present study is to scientifically,verify the antidiabetic activity/potency of Vernonia amygdalina in human diabetes.Methods:A search was made at Nnewi,South - East Nigeria for known diabetes who use ...Objective:Aim of present study is to scientifically,verify the antidiabetic activity/potency of Vernonia amygdalina in human diabetes.Methods:A search was made at Nnewi,South - East Nigeria for known diabetes who use Vernonia amygdalina either as their sole or supplementary antidiabetic.A total of ten volunteers comprising, eight females and two males were recruited.They were all of age range of 36-50 and average weight of 78 kg and suffering from non - insulin form of diabetes.The purpose of the study was explained to them and their consent obtained.They were asked not to take any other antidiabetic outside Vernonia amygdalina throughout the four weeks study period.There was however,no form of restrictions to their choice of diet or life style. They were requested to abstain from any drugs a week prior to commencement of study.Their prescriber’s dosage range was followed and minimum daily dose of 210 mL(approximately 220 mg of dry extract) was administered in Week-1,followed by daily dose of 420 mL(440 mg) in Week-2.In Week-3 they received 630 mL (660 mg) daily dose and in Week-4,they received daily dose of 840 mL(880 mg).Their fasting blood sugar were estimated pre-crude drug administration and on weekly basis for the four week study period.Their weekly weights were measured to check for possible weight gain or loss.Results were subjected to statistical analysis and Students T-Test was used to calculate P-value.P-value≤0.05 were considered significant.Results:It was observed that all the volunteers in the study group were taking Vernonia amygdalina only as supplementary. Two volunteers dropped out of the study at the end of Week-3 leaving us with 8 in Week-4.There was no significant bodyweight change within the four week study.The starting mean fasting blood sugar which was 133.3 mg/dL(7.41 mmol/L) rose to 136.6 mg/dL(7.59 mmol/L) in Week-1,to 149.5 mg/dL(8.31 mmol/L) in Week-2 and to 166.5 mg/dL(9.30 mmol/L) in Week-3.Week-4 had us left with 8 volunteers with a mean of 190.6 mg/dL(10.59 mmol/L).There was s展开更多
Objective:To evaluate the antiarthritic activity of water extract of leaves of Vernonia amygdalina(V.A.) on arthritis induced model of rats.Methods:Arthritis was induced in male albino Wister rats by injection of crot...Objective:To evaluate the antiarthritic activity of water extract of leaves of Vernonia amygdalina(V.A.) on arthritis induced model of rats.Methods:Arthritis was induced in male albino Wister rats by injection of croton oil(0.1 mL) into the left foot pad of the animals.Treatment with V.A.at 200 and 400 mg/kg and standard Indomethacin(0.3 mg/kg) was started on the same day and continued up to the 12th day.The paw volume was measured on the 1st,5th,12th and 21st day,respectively for both the paws and anti-arthritic activity was evaluated.Results:The extract of V.A.produced reduction in the inflammation of the paw due to croton oil.The antiarthritic action started on the 5th day and continued till the 12th day and the activity was comparable to that of the standard on both days.V.A.significantly inhibited adjuvant induced arthritis and had significant ant-inflammatory effect(P【0.05).Conclusion:This report therefore clearly showed that V.A.significantly inhibited adjuvant induced arthritis in rats as it significantly reduced the paw volume on the 12th day and may explain the effectiveness of this plant when used in the tropics for the treatment of arthritis.展开更多
文摘Objective:To investigate the anti-inflammatory activity of the extract of Vernonia amygdalina (V.A).Methods:Inflammatory response was induced by topical application of croton oil dissolved in suitable vehicle on the rat ear.After 6 hrs,cutting out the ear quantitated the response.The cut ear was weighed and the increase in weight relative to control group was evaluated.Results:When co-applied with croton oil to the rat ear extract of V.A.produced a reduction in the inflammatory response when croton oil alone was applied to the rat ear.The extract produced(69.1 +2.0)%reduction of the inflammatory response produced by croton oil alone,lower than the reduction of the inflammatory response produced by acetyl salicylic acid[(71.1±2.0)%].Conclusions:This finding suggests that extract of V.A.exhibits antiinflammatory activity and may explain the usefulness of the leaves of this plant in the treatment of inflammatory disease conditions by traditional healers.
文摘Vernonia amygdalina Del. is one of the leafy vegetables that can be used in an attempt to alleviate the problem of micronutrient malnutrition, prominent in tropical Africa. In order to ensure availability in non-growing areas or seasons, the vegetable needs to be preserved. Processing and preservation methods influence the nutrient content of vegetables. The present study was aimed at determining the effects of preservation on two different varieties of V. amygdalina (bitter) leaves (broad and small leaves). To this effect, evaluations were made on the chlorophyll content, phytochemicals, and antioxidant capacity of the two varieties of bitter leaf (V. amygdalina Del.) stored at 4℃ and –20℃ over a period of two weeks. Results showed a significant decrease in all parameters studied for both varieties at –20℃ except for the free radical reducing power (FRAP), DPPH radical scavenging activity (%RSA) and nitric oxide radical scavenging activity (%RSA) of V. amygdalina broad leaves where increase in scavenging activity was observed. Thus, it was concluded that to preserve the chlorophyll, phenol, total soluble proteins and reducing sugar levels, preservation at 4℃ is recommended. The present study finding would be useful during short-term preservation of bitter leaves for soup preparation and/or its aqueous extract for ethnomedicinal purposes, especially the small leaf variety.
文摘Breast cancer is the second leading cause of cancer-related deaths of women in the United States. Fortunately, the mortality rate from breast cancer has decreased in recent years due to an increased emphasis on early detection and more effective treatments. Although great advancements have been made in the treatment and control of cancer progression, significant deficiencies and room for improvement remain. The central objective of this research was to further determine the in vitro mechanisms of Vernonia amygdalina (VA) leaf extracts as an anticancer candidate for the treatment of breast cancer. To achieve our objective, MCF-7 cells were treated with different concentrations of VA for 24 hand 48 h. Cell viability, live and dead cells were determined by the means of trypan blue exclusion test. Live and dead cells were further evaluated by propidium iodine (PI) assay using the Cellometer Vision. Cell apoptosis was measured by flow cytometry assessment using annexin V/PI kit. Data obtained from the trypan blue test demonstrated that VA treatment reduces cell viability in a concentration- and time-dependent manner. Result of the PI assay showed a gradual increase in the population of necrotic cells (fluorescence positive cells) in VA-treated cells compared to the control cells (fluorescence negative cells). Treatment of these cancer cells (MCF-7) for 48 h at concentrations ranging from 250 μg/mL to 1000 μg/mL caused early signs of apoptosis resulting from phosphatidylserine externalization as judged by annexin V assay. We observed a strong concentration-response relationship with regard to VA exposure and annexin V/PI positive cells. In summary, our finding demonstrates that VA-induced cytotoxicity and apoptosis in MCF-7 cells involve phosphatidylserine externalization accompanied by secondary necrotic cell death. With previous findings in our laboratory, the data generated in the present study confirms that VA is a valuable botanical therapeutic agent for the treatment of breast cancer.
文摘The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and 91% Al was sand cast at the Foundry Shop of the National Metallurgical Development Centre, Jos, Nigeria. The cast alloy was cut and machined to corrosion coupons and immersed into 0.5 M NaOH solution containing varying inhibitor concentrations (0.1%, 0.2%, 0.3%, 0.5% v/v) within a period of fifteen days. From the result, it was found that the adsorption of Vernonia amygdalina reduced the corrosion rate of this group of alloy in the alkaline medium. The inhibitive action of this plant extract was explained using inhibition efficiency and degree of surface coverage. The most suitable inhibitor concentration was found to be 0.5% with inhibition efficiency of 87%. The mechanism of inhibition is by physical adsorption and the adsorbed molecules of the inhibitor lies on the surface of the alloy blocking the active corrosion sites on the alloy, hence, giving the alloy a higher corrosion resistance in the studied environment.
文摘In this work, adsorption and thermodynamics study of the inhibition of corrosion of mild steel in H2SO4 medium using Vernonia amygdalina was carried out. The inhibitive and adsorptive properties of ethanol extract of Vernonia amygdalina for the corrosion of mild steel in 0.2 M H2SO4 solutions was investigated using weight loss technique. The result has proved that that the extract is a good inhibitor of corrosion of mild steel in H2SO4. The inhibition efficiencies ranged from 23.37 to 38.59% and from 22.45 to 35.78% at 303 and 323K respectively. The inhibition efficiency of the extract decreased as temperature and time of immersion increased but increased with increase in concentration of extract. The adsorption of the inhibitor on surface of mild steel was found to be exothermic, spontaneous and consistent with the mechanism of physical adsorption as the value for heat of adsorption ranged from -2.12 to -4.87KJ mol–1. The adsorption data fitted well to Langmuir, Temkin, Frumkin and Flory-Huggins adsorption isotherms.
文摘Objective:Aim of present study is to scientifically,verify the antidiabetic activity/potency of Vernonia amygdalina in human diabetes.Methods:A search was made at Nnewi,South - East Nigeria for known diabetes who use Vernonia amygdalina either as their sole or supplementary antidiabetic.A total of ten volunteers comprising, eight females and two males were recruited.They were all of age range of 36-50 and average weight of 78 kg and suffering from non - insulin form of diabetes.The purpose of the study was explained to them and their consent obtained.They were asked not to take any other antidiabetic outside Vernonia amygdalina throughout the four weeks study period.There was however,no form of restrictions to their choice of diet or life style. They were requested to abstain from any drugs a week prior to commencement of study.Their prescriber’s dosage range was followed and minimum daily dose of 210 mL(approximately 220 mg of dry extract) was administered in Week-1,followed by daily dose of 420 mL(440 mg) in Week-2.In Week-3 they received 630 mL (660 mg) daily dose and in Week-4,they received daily dose of 840 mL(880 mg).Their fasting blood sugar were estimated pre-crude drug administration and on weekly basis for the four week study period.Their weekly weights were measured to check for possible weight gain or loss.Results were subjected to statistical analysis and Students T-Test was used to calculate P-value.P-value≤0.05 were considered significant.Results:It was observed that all the volunteers in the study group were taking Vernonia amygdalina only as supplementary. Two volunteers dropped out of the study at the end of Week-3 leaving us with 8 in Week-4.There was no significant bodyweight change within the four week study.The starting mean fasting blood sugar which was 133.3 mg/dL(7.41 mmol/L) rose to 136.6 mg/dL(7.59 mmol/L) in Week-1,to 149.5 mg/dL(8.31 mmol/L) in Week-2 and to 166.5 mg/dL(9.30 mmol/L) in Week-3.Week-4 had us left with 8 volunteers with a mean of 190.6 mg/dL(10.59 mmol/L).There was s
文摘Objective:To evaluate the antiarthritic activity of water extract of leaves of Vernonia amygdalina(V.A.) on arthritis induced model of rats.Methods:Arthritis was induced in male albino Wister rats by injection of croton oil(0.1 mL) into the left foot pad of the animals.Treatment with V.A.at 200 and 400 mg/kg and standard Indomethacin(0.3 mg/kg) was started on the same day and continued up to the 12th day.The paw volume was measured on the 1st,5th,12th and 21st day,respectively for both the paws and anti-arthritic activity was evaluated.Results:The extract of V.A.produced reduction in the inflammation of the paw due to croton oil.The antiarthritic action started on the 5th day and continued till the 12th day and the activity was comparable to that of the standard on both days.V.A.significantly inhibited adjuvant induced arthritis and had significant ant-inflammatory effect(P【0.05).Conclusion:This report therefore clearly showed that V.A.significantly inhibited adjuvant induced arthritis in rats as it significantly reduced the paw volume on the 12th day and may explain the effectiveness of this plant when used in the tropics for the treatment of arthritis.