Objective:To investigate thein vitroantioxidant potential of Carica papaya(C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation.Methods:H...Objective:To investigate thein vitroantioxidant potential of Carica papaya(C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation.Methods:Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract(at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage.Results:Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities usingin vitro models in a concentration dependent manner(P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid(P<0.05). The IC50values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid(the reference antioxidant) possessed higher activity than the extract.Conclusions:The findings show that C. papayaleaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy.Thus, the leaves can be exploited for pharmaceutical and nutritional purposes.展开更多
ObjectiveTo investigate the effect of the anthocyanin-rich extract of Hibiscus sabdariffa (H. sabdariffa) calyx on the viability of cadmium-treated U937 cells and cadmium-mediated activation of U937-derived macrophage...ObjectiveTo investigate the effect of the anthocyanin-rich extract of Hibiscus sabdariffa (H. sabdariffa) calyx on the viability of cadmium-treated U937 cells and cadmium-mediated activation of U937-derived macrophages.MethodsThe macrophage cell line U937 was treated with cadmium (0.1 μ mol/L) and later incubated with the anthocyanin-rich extract and cell viability was assessed via trypan blue staining. In the other experiment, the U937 cells were transformed to the macrophage form by treatment with phorbol 12, myristate 13, and acetate and incubated with cadmium (10 μ mol/L). The anthocyanin-rich extract was added to the cells later and subsequently, the supernatant of each cell culture was analysed for the production of tumour necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), nitric oxide, and catalase activity as indices for the activation of macrophages.ResultsIt revealed that the anthocynanin-rich extract significantly (P < 0.05) increased the viability of the cells which was suppressed by cadmium when compared to quercetin dihydrate. The extract also reduced the cadmium-mediated production of the markers of macrophage-activation when compared to quercetin dihydrate. In both experiments, the activity of the extract was concentration-dependent (P < 0.05).ConclusionsThe findings show that H. sabdariffa possesses significant immunoprotective effect. These corroborate the immense reported antioxidant and medicinal potential of the calyces of the plant which could be exploited for pharmacological and neutraceutical advantages.展开更多
Objective:To investigate the abilities of two flavonoids - Garcinia hiflavanol-1(GB-1) and Garcinia biflavanol-2(GB-2) from Garcinia kola(G.kola) in reducing cadmium-induced effects on raw U937 cells and 11937-derived...Objective:To investigate the abilities of two flavonoids - Garcinia hiflavanol-1(GB-1) and Garcinia biflavanol-2(GB-2) from Garcinia kola(G.kola) in reducing cadmium-induced effects on raw U937 cells and 11937-derived macrophages.Methods:Macrophage U937 cells were incubated with cadmium followed by treatment with the flavonoids and cell viability assessed via trypan blue staining.In the other experiment,the U937 cells were transformed to the macrophage form and treated with cadmium in order to activate them.The cells were later incubated with the flavonoids and finally the supernatant of each cell culture was analysed for the secretion of nitric oxide,catalyse activity,and the release of tumour necrosis factor-alpha,interleukin-1 and interleukin-2 as indices of macrophage activation.Quercetin(a flavonol) was used as the reference flavonoid in all experiments.Results:It revealed that the flavonoids significantly increased the viability of the cells and also reduced the cadmium-induced activation of the macrophage cells in a concentration-dependent manner.The flavanols GB-1 and GB-2 possessed higher activities than quercetin in all cases(P【0.05).Garcinia biflavanol-2 possessed a higher bioactivity than GB-1 significantly(P【0.05).Conclusions:In addition to corroborating the several reported importance of G.kola as a potential neutraceutical and pharmacological condiment,the study also clearly indicates the role hydroxylation especially at the 3’- position of polyphenols could play in enhancing bioactivities of flavonoids.展开更多
The plant kingdom is an important potential source of effective treatment for various diseases.Most herbs have long been used for medicinal purposes,and plant metabolites with their derivatives had been used in ethnom...The plant kingdom is an important potential source of effective treatment for various diseases.Most herbs have long been used for medicinal purposes,and plant metabolites with their derivatives had been used in ethnomedicine.However,concerns exist about the quality and safety of herbal medicine products,particularly relating to safety,dosage,and mechanism of action.This mini review reveals some insights about the Hunteria umbellate seed,which is similar to that of insulin secretagogue metformin.Studies have validated its beneficial role in hyperglycemic,insulin resistance and obesity conditions,which are components of metabolic syndrome.However,none of these studies evaluated the mechanisms by which this plant extract performs its antihyperglycemic,insulin resistance and anti-obesity actions in metabolic syndrome.This understanding would provide considerable progress toward drug design using this plant material.Hence the need for this awareness to sensitize the researchers in this field who are passionate about drug design to consider the pathways discussed below for Hunteria umbellata seeds.Hunteria umbellata seed extract may represent a new therapeutic strategy for type-2 diabetes in place of metformin if it is well-studied.展开更多
The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Rat...The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.展开更多
文摘Objective:To investigate thein vitroantioxidant potential of Carica papaya(C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation.Methods:Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract(at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage.Results:Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities usingin vitro models in a concentration dependent manner(P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid(P<0.05). The IC50values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid(the reference antioxidant) possessed higher activity than the extract.Conclusions:The findings show that C. papayaleaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy.Thus, the leaves can be exploited for pharmaceutical and nutritional purposes.
文摘ObjectiveTo investigate the effect of the anthocyanin-rich extract of Hibiscus sabdariffa (H. sabdariffa) calyx on the viability of cadmium-treated U937 cells and cadmium-mediated activation of U937-derived macrophages.MethodsThe macrophage cell line U937 was treated with cadmium (0.1 μ mol/L) and later incubated with the anthocyanin-rich extract and cell viability was assessed via trypan blue staining. In the other experiment, the U937 cells were transformed to the macrophage form by treatment with phorbol 12, myristate 13, and acetate and incubated with cadmium (10 μ mol/L). The anthocyanin-rich extract was added to the cells later and subsequently, the supernatant of each cell culture was analysed for the production of tumour necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), nitric oxide, and catalase activity as indices for the activation of macrophages.ResultsIt revealed that the anthocynanin-rich extract significantly (P < 0.05) increased the viability of the cells which was suppressed by cadmium when compared to quercetin dihydrate. The extract also reduced the cadmium-mediated production of the markers of macrophage-activation when compared to quercetin dihydrate. In both experiments, the activity of the extract was concentration-dependent (P < 0.05).ConclusionsThe findings show that H. sabdariffa possesses significant immunoprotective effect. These corroborate the immense reported antioxidant and medicinal potential of the calyces of the plant which could be exploited for pharmacological and neutraceutical advantages.
文摘Objective:To investigate the abilities of two flavonoids - Garcinia hiflavanol-1(GB-1) and Garcinia biflavanol-2(GB-2) from Garcinia kola(G.kola) in reducing cadmium-induced effects on raw U937 cells and 11937-derived macrophages.Methods:Macrophage U937 cells were incubated with cadmium followed by treatment with the flavonoids and cell viability assessed via trypan blue staining.In the other experiment,the U937 cells were transformed to the macrophage form and treated with cadmium in order to activate them.The cells were later incubated with the flavonoids and finally the supernatant of each cell culture was analysed for the secretion of nitric oxide,catalyse activity,and the release of tumour necrosis factor-alpha,interleukin-1 and interleukin-2 as indices of macrophage activation.Quercetin(a flavonol) was used as the reference flavonoid in all experiments.Results:It revealed that the flavonoids significantly increased the viability of the cells and also reduced the cadmium-induced activation of the macrophage cells in a concentration-dependent manner.The flavanols GB-1 and GB-2 possessed higher activities than quercetin in all cases(P【0.05).Garcinia biflavanol-2 possessed a higher bioactivity than GB-1 significantly(P【0.05).Conclusions:In addition to corroborating the several reported importance of G.kola as a potential neutraceutical and pharmacological condiment,the study also clearly indicates the role hydroxylation especially at the 3’- position of polyphenols could play in enhancing bioactivities of flavonoids.
文摘The plant kingdom is an important potential source of effective treatment for various diseases.Most herbs have long been used for medicinal purposes,and plant metabolites with their derivatives had been used in ethnomedicine.However,concerns exist about the quality and safety of herbal medicine products,particularly relating to safety,dosage,and mechanism of action.This mini review reveals some insights about the Hunteria umbellate seed,which is similar to that of insulin secretagogue metformin.Studies have validated its beneficial role in hyperglycemic,insulin resistance and obesity conditions,which are components of metabolic syndrome.However,none of these studies evaluated the mechanisms by which this plant extract performs its antihyperglycemic,insulin resistance and anti-obesity actions in metabolic syndrome.This understanding would provide considerable progress toward drug design using this plant material.Hence the need for this awareness to sensitize the researchers in this field who are passionate about drug design to consider the pathways discussed below for Hunteria umbellata seeds.Hunteria umbellata seed extract may represent a new therapeutic strategy for type-2 diabetes in place of metformin if it is well-studied.
文摘The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.
