Curative Test Research Articles

Triple Artemisinin-based Combination Therapy (TACT): Efficacy of dihydroartemisinin-piperaquine plus chloroquine against Plasmodium berghei ANKA strains with different drug sensitivities in a murine malaria model.

BackgroundEvident detection of artemisinin resistance markers in patient isolates of Plasmodium falciparum from East Africa threatens the efficacy of artemisinin-based combination therapies (ACTs) as first-line treatment of malaria in sub-Saharan Africa. Repositioning previously used antimalarials as complementary addition to ACTs has been suggested as a viable option to mitigating this threat. This study evaluated the potential benefit of chloroquine (CQ) as a complementary partner to dihydroartemisinin/piperaquine (DHA/PQ) in the treatment of malaria in a mice model. MethodsThe comparative efficacy of the combination of DHA/PQ/CQ and DHA/PQ against two strains of Plasmodium berghei ANKA (MRA 311 and 671) with different levels of sensitivities to chloroquine was evaluated in separate experiments. Parasitological activities including; parasite suppression time, parasite clearance time, recrudescence time, and parasite reduction ratio were evaluated in vivo. The mean survival time was also monitored throughout the duration of the study. ResultsIn both parasite lines, 99.99% chemo-suppression was observed on day 4 in the drug treatment groups (CQ alone, DHA/PQ and DHA/PQ/CQ). In the curative test, there were significant differences between DHA/PQ/CQ and DHQ/PQ treatment, highlighted by reduced parasite clearance time (4.75±0.3 Vs 5.5±0.3 days, P<0.05), significantly delayed recrudescence time (28.5±1.04 Vs 13.3±0.48 days, P<0.01), a 1.5-fold change in parasite reduction ratio, and a prolonged mean survival time (34.5±1.04 Vs 26.7±0.48 days, P<0.05). ConclusionThe addition of chloroquine to dihydroartemisinin-piperaquine may be beneficial in the treatment of malaria, especially in areas where malaria parasite sensitivity to chloroquine is predominant.

Antimalarial potentials of Solanum dasyphyllum fractions against Plasmodium berghei infected mice

BackgroundThe leaves of Solanum dasyphyllum are commonly utilized in the management of fever in traditional medicine, yet scientific evidence supporting their antimalarial effectiveness is lacking. ObjectiveThus, this study aimed to assess the antioxidant properties of solvent fractions derived from these leaves, alongside investigating antimalarial potential against Plasmodium berghei in mice. MethodsAntioxidant activity was evaluated through total phenolic content determination, DPPH radical scavenging, and Ferric ion reducing antioxidant power assay. The fractions were tested against Plasmodium berghei (NK65) in 4-day suppressive, prophylaxis, and curative models, with mice orally administered 1% Tween80 (control), Solanum dasyphyllum hexane fraction (SdHXF), Solanum dasyphyllum dichloromethane fraction (SdDMF), Solanum dasyphyllum ethyl-acetate fraction (SdEAF), and Solanum dasyphyllum aqueous fraction (SdAQF) (each at 125mg/kg), and chloroquine (10 mg/kg). IC50 values were determined via linear regression analysis, and antimalarial study results were statistically analyzed using one-way ANOVA followed by Duncan multiple range tests, considering significance at P value < 0.05. ResultsThe SdHXF (60.4%), SdDMF (56.8%), SdEAF (86.4%), and SdAQF (94.8%) exhibited notable percentage chemosuppression compared to the control in the 4-day suppressive test. In the prophylaxis test, SdEAF (80.6%) and SdAQF (80.0%) demonstrated similar percentage chemosuppression. In the curative test, the mean survival time significantly increased in SdHXF (30.2 ± 1.3 days), SdDMF (30.8 ± 3.2 days), SdEAF (31.4 ± 2.3 days), and SdAQF (30.1 ± 2.0 days) compared to the control (10.3 ± 0.1 days). The antioxidant activity of the fractions increased with concentration; however, it was lower than that of the positive controls (gallic acid and ascorbic acid). ConclusionThese results suggest that the fractions possess potent antiplasmodial activity against Plasmodium berghei, particularly in the mid-polar fractions, indicating the potential of the plant as a source of novel antimalarial agents.

Effect of Justicia insularis Leaf Extract and Fractions on Oxidative Stress Markers, Liver Function Parameters and Liver Histology of Plasmodium berghei -Infected Mice

Justicia insularis (Family-Acanthaceae) is used in Ibibio ethnomedicine to treat malaria. The leaf extract and fractions of J. insularis were investigated for antioxidative stress and hepatoprotective activities in Plasmodium berghei-infected mice. The leaf extract (100-300 mg/kg, p.o.) exerted significant (p&lt;0.05) antimalarial activity against P. berghei infection in curative test with ethyl acetate fraction demonstrating the highest activity. The extract/fractions treatment caused significant (p&lt;0.05) reductions in liver enzymes (ALT, AST and ALP), total and conjugated bilirubin of the treated infected mice and also decreased significantly (p&lt;0.05) total protein and albumin levels of the treated mice relative to control. The leaf extract and fractions further improved significantly (p&lt;0.05) the levels of oxidative stress markers enzymes and molecules (CAT, GPx, GST, SOD) of the treated infected mice with no significant (p&gt;0.05) effect on GSH. The MDA levels in the livers of the treated infected mice were significantly (p&lt;0.05) reduced relative to control. Histology of liver sections revealed absence or significant reductions in pathological features in infected mice treated with leaf extract (100 mg/kg), DCM and ethyl acetate fractions compared to untreated infected mice. These results suggest that the leaf extract/fractions of Justicia insularis possess antioxidative stress and hepatoprotective potentials, which is an added advantage to its antimalarial property.

In vitro, in vivo and in silico antiplasmodial profiling of the aqueous extract of Hibiscus asper HOOK F. Leaf (Malvaceae)

Ethnopharmacological relevancePlasmodium resistance to antimalarial drugs raises the urgent need to seek for alternative treatments. Aqueous extract of Hibiscus asper leaves is currently used in malaria management but remains less documented.Aim of the study: The study aims to evaluate antimalarial effects of the aqueous extract of Hibiscus asper. UHPLC/MS, was used to identify some likely compounds present in the plant that were thereafter docked to some malaria parasite proteins. Study designIn vitro anti-plasmodium and antioxidant, UHPLC/Ms analysis, in vivo antimalarial of the plant extract, and in silico molecular docking prediction of some identified compounds were performed to investigate the pharmacological effects of H. asper. Material and methodsThe in vitro antiplasmodial activity of the extract was carried out on Plasmodium falciparum strains using SYBR-green dye; then, the curative antimalarial activity was conducted on Plasmodium berghei NK65-infected male Wistar rats. The UHPLC/MS analysis was used to identify plant compounds, followed by interactions (docking affinity) between some compounds and parasitic enzymes such as P. falciparum purine nucleoside phosphorylase (2BSX) and 6-phosphogluconate dehydrogenase (6FQY) to explore potential mechanisms of action at the molecular level. ResultsNo hemolysis effect of the extract was observed at concentrations up to 100 mg/mL. In vitro test of the aqueous leaves extract of H. asper showed inhibitory activity against P. falciparum Dd2 and 3D7 strains with IC50 values of 19.75 and 21.97 μg/mL, respectively. The curative antimalarial test of the H. asper extract in infected rats exhibited significant inhibition of the parasite growth (p < 0.001) with inhibition percentage of 95.11%, 97.68% and 95.59% at all the doses (50, 100 and 200 mg/kg) respectively. The extract corrected major physiological alterations such as liver and kidney impairments, oxidative stress and architectural disorganization in liver, spleen and kidneys tissues. The UHPLC/MS analysis identified 7 compounds, namely chlorogenic acid, azulene, quercetin, rhodine, 1-ethyl-2,4-dimethyl benzene and phthalan. Out of seven compounds identified in the extract quercetin and phthalan showed higher in silico inhibitory activity against P. falciparum purine nucleoside phosphorylase and Plasmodium falciparum 6-phosphosgluconate dehydrogenase parasite enzymes. ConclusionThese findings indicate that H. asper could be a promising complementary medicine to manage malaria. Meanwhile, the affinity of annoted compounds with these enzymes should be further confirmed.

Antimalarial efficacy test of the aqueous crude leaf extract of Coriandrum sativum Linn.: an in vivo multiple model experimental study in mice infected with Plasmodium berghei

BackgroundMalaria continues to wreak havoc on the well-being of the community. Resistant parasites are jeopardizing the treatment. This is a wake-up call for better medications. Folk plants are the key starting point for antimalarial drug discovery. After crushing and mixing the leaves of Coriandrum sativum with water, one cup of tea is drunk daily for a duration of three to five days as a remedy for malaria by local folks in Ethiopia. Additionally, in vitro experiments conducted on the plant leaf extract elsewhere have also demonstrated the plant’s malaria parasite inhibitory effect. There has been no pharmacologic research to assert this endowment in animals, though. This experiment was aimed at evaluating the antimalarial efficacy of C. sativum in Plasmodium berghei infected mice.MethodsThe plant's leaf was extracted using maceration with distilled water. The extract was examined for potential acute toxicity. An evaluation of secondary phytoconstituents was done. Standard antimalarial screening models (prophylactic, chemosuppressive, curative tests) were utilized to assess the antiplasmodial effect. In each test, thirty mice were organized into groups of five. To the three categories, the test substance was given at doses of 100, 200 and 400 mg/kg/day before or after the commencement of P. berghei infection. Positive and negative control mice were provided Chloroquine and distilled water, respectively. Rectal temperature, parasitemia, body weight, survival time and packed cell volume were ultimately assessed. Analysis of the data was performed using Statistical Package for Social Sciences.ResultsNo toxicity was manifested in mice. The extract demonstrated a significant inhibition of parasitemia (p < 0.05) in all the models. The inhibition of parasite load was highest with the upper dose in the suppressive test (82.74%) followed by the curative procedure (78.49%). Likewise, inhibition of hypothermia, weight loss hampering, improved survival and protection against hemolysis were elicited by the extract.ConclusionsThe results of our experimental study revealed that the aqueous crude leaf extract of C. sativum exhibits significant antimalarial efficacy in multiple in vivo models involving mice infected with P. berghei. Given this promising therapeutic attribute, in depth investigation on the plant is recommended.

Antimalarial Studies and Phytochemical Profiling of Laportea aestuans (L.) Chew Extractives

Background and objectives This study validated the antimalarial efficacy of Laportea aestuans extract using chemosuppressive and curative models, identified its most active fraction, and performed chemical profiling of the active fraction. Methodology The aerial part of L. aestuans (LA) was extracted with 80% methanol and assayed for its chemosuppressive and curative antimalarial activities through the oral administration of the extract (100, 200, 400 and 800 mg/kg) to groups consisting of five mice each. The extract was thereafter suspended in water and partitioned with dichloromethane to afford the dichloromethane (DLA) and aqueous (ALA) fractions. The fractions (10, 20, 40, and 80 mg/kg) were thereafter tested for their antimalarial activity followed by GC-MS analysis of the most active fraction. Results The toxicity level was found to be above 2000 mg/kg. The activity recorded for the four-day chemosuppressive antimalarial tests showed a dose-dependent activity up to 400 mg/kg. The activity was significantly lower than that of chloroquine. The antimalarial activity of the extract at the lowest dose of 100 mg/kg was 42%. In the curative test, the extract of LA gave a dose-dependent activity that was significantly higher than the negative control. The DLA and ALA fractions gave a comparable curative activity across all doses. At 10 mg/kg, ALA and DLA gave percentage clearance of 81.25 ± 1.84 and 87.45 ± 1.35, respectively, which were significantly higher than that of the negative control (0.00 ± 0.00) and significantly lower than that of the positive control (94.93 ± 0.26). The chemical profiling revealed the presence of non-polar and medium-polar constituents in the dichloromethane fraction. Conclusion The good antimalarial activity elicited by LA extractives supports its usage in ethnomedicine as an antimalarial agent.

Efficacy of Albizia malacophylla (A.Rich.) Walp. (Leguminosae) methanol (80%) leaf extract and solvent fractions against Plasmodium berghei-induced malaria in mice model

Ethnopharmacological relevanceNovel drugs are needed to address the issue of malarial infection resistance; natural items can be a different source of these medications. Albizia malacophylla (A. Rich.) Walp. (Leguminosae) is listed as one of the antimalarial medicinal plants in Ethiopian folk medicine. However, there are no reports regarding the biological activity or phytochemistry of the plant. Aim of the studyThus, this study aimed to evaluate the A. malacophylla crude extract and solvent fractions' in vivo antimalarial activity utilizing 4-day suppressive, preventative, and curative tests in mice infected with P. berghei. Materials and methodsThe parasite Plasmodium berghei, which causes rodent malaria, was used to infect healthy male Swiss Albino mice, weighing 23–28 g and aged 6–8 weeks. Solvent fractions such as methanol, water, and chloroform were given in addition to an 80% methanolic extract at 100, 200, and 400 mg/kg doses. A Conventional test such as parasitemia, survival time, body weight, temperature, and packed cell capacity were employed to ascertain factors such as the suppressive, curative, and preventive tests. ResultsEvery test substance dramatically reduced the number of parasites in every experiment. Crude extract (with the highest percentage suppression of 67.78%) performs better antimalarial effect than the methanol fraction, which is the most efficient solvent fraction with a percentage suppression of 55.74%. With a suppression value of 64.83% parasitemia level, the therapeutic effects of 80% methanolic crude extract were greater than its curative and preventative effects in a four-day suppressive test. The survival period (17 days) was longer with the hydroalcoholic crude extract dose of 400 mg/kg than with other doses of the materials under investigation. ConclusionsThe results of this investigation validate the antimalarial characteristics of A. malacophylla leaf extract. The crude extract prevented weight loss, a decline in temperature, and a reduction in PCV. The results demonstrate that the plant has a promising antimalarial effect against P. berghei, hence supporting the traditional use of the plant. Therefore, it could serve as a foundation for the development of new antimalarial drugs.

Biofilm of Cutibacterium acnes: a target of different active substances.

Acne vulgaris is a chronic inflammatory dermatosis. Cutibacterium acnes plays a crucial role in the acne pathophysiology. Recent works present evidence of C.acnes growing as a biofilm in cutaneous follicles. This development is currently considered one of the leading causes of C. acnes in vivo persistence and resistance to antimicrobials used to treat acne. Our objective was to evaluate the effects of various active compounds (clindamycin, erythromycin, doxycycline, and myrtle extract) on eight distinct, well-characterized strains of C. acnes following their growth in biofilm mode. Cutibacterium acnes isolates from phylotypes IA1 and IA2 produce more biofilm than other phylotypes. No antibiotic effect was observed either during the curative test or preventive test. Myrtle extract at 0.01% (w/v) showed significant efficacy on the biofilm for C. acnes strains (curative assays). Furthermore, it appear that myrtle extract and doxycycline together reduce the overall biomass of the biofilm. A significant dose-dependent effect was observed during the preventive test, greater than the one observed under curative conditions, with an important loss of activity of the myrtle extract observed from 0.001% (w/v) concentration onwards. Transmission electron microscopy showed that bacteria treated withmyrtle extract grew biofilms much less frequently than untreated bacteria. Additionally, when the quantity of myrtle extract grew, the overall number of bacteria dropped, indicating an additional antibacterial action. These findings support the hypothesis that the different C. acnes phylotypes have various aptitudes in forming biofilms. They also suggest that myrtle extract is a promising alternative as an anti-biofilm and antibacterial agent in fighting diseases caused by planktonic and biofilm C. acnes.

Antimicrobial and Antiplasmodial Activities of Endophytic Fungi Associated with Psidium guajava

Infections due to antimicrobial-resistant microorganisms have become widespread in recent years. Thus, searching for novel antimicrobial agents to combat such pathogens has become crucial. The current study aimed to evaluate the antimicrobial, antiplasmodial, and immunomodulatory activities of the extracts of endophytic fungi isolated from Psidium guajava. Isolation, identification, fermentation, and extraction of the secondary metabolites of the fungal endophytes were carried out following standard procedures. The extracts were subjected to High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) analysis to detect their bioactive components. The Antimicrobial activity and Minimum Inhibitory Concentration of the fungal extracts were evaluated against pure cultures of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumonia using Agar well diffusion and Agar dilution method respectively. The acute toxicity study (LD50) was carried out using Lorke’s method. The extracts were tested in vivo in mice for antiplasmodial activity against Plasmodium berghei and in vitro against Plasmodium falciparum using Peter and Reyley's curative test method and WHO standardized micro-test system with modification respectively. The immunomodulatory activity of the extracts was evaluated by cyclophosphamide-induced myelosuppression (hematological parameters). Active extracts were further subjected to Delayed-Type Hypersensitivity Response (DTHR) and Haemagglutination Inhibition Assay using Sheep Red Blood Cells as antigens. The result showed Alternaria sp. (PGL1, PGL2, PGL3), from P. guajava. The HPLC-DAD analysis revealed the presence of bioactive compounds previously reported to have antimicrobial, antiplasmodial, and immunomodulatory properties. The fungal extracts exhibited varying degrees of antimicrobial activity. The LD50 of the fungi extracts was&gt;5000 mg/kg in mice. The extracts at 100 and 200 mg/kg body weight in mice showed varying degrees of antiplasmodial activity. Growth of P. berghei was significantly (p&lt;0.001) inhibited, curative effect ranges from 59.09 – 100%. Schizont maturation of P. falciparum isolates was inhibited and the highest level of inhibition was observed at 1 mg/ml (p&lt;0.05). The fungal extracts reversed the effect of cyclophosphamide-induced reduction in total white blood cell counts and % neutrophil. This study showed that the tested plant harbors species of endophytic fungi that contain numerous secondary metabolites. The endophytic fungi showed prophylactic, immunostimulatory, and antiplasmodial activities, which can be exploited to develop antimicrobial, antiplasmodial, and immunomodulatory agents.

In vitro and in vivo antimalarial activities of the ethanol extract of Erythrina sigmoidea stem bark used for the treatment of malaria in the Western Region of Cameroon

BackgroundMalaria is one of the leading causes of morbidity and/or mortality in tropical Africa. The spread and development of resistance to chemical antimalarial drugs and the relatively high cost of the latter are problems associated with malaria control and are reasons to promote the use of plants to meet healthcare needs to treat malaria. The aim of this study was to evaluate antiplasmodial activities of extracts of Erythrina sigmoidea (Mah quat), which is traditionally used for the treatment of malaria in the western region of Cameroon.Material and methodsThe ethanol extract of E. sigmoidea stem bark was obtained through the maceration process using 95% ethanol, while the aqueous extract was prepared by infusion. The in vitro antiplasmodial effect of extracts against P. falciparum chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains was determined using the Trager and Jensen method. On the other hand, the in vivo antimalarial activity of the extract was evaluated in mice infected with Plasmodium berghei strain NK65 using the Peters’ 4-day suppressive test and Ryley test (curative test). A total of 36 mice were used, subdivided into six groups of six mice each: one normal control, a negative control, a positive control, and three other groups for the tested product. Blood samples were collected on the 10th day of each test for hematological parameters.ResultsThe aqueous extract had an in vitro antiplasmodial activity against the chloroquine-sensitive strain with an IC50 of 29.51 ± 3.63 µg/mL and against the chloroquine-resistant strain with an IC50 of 35.23 ± 3.17 µg/mL. The highest in vitro antiplasmodial activity was observed with the ethanol extract against the chloroquine-sensitive strain with an IC50 of 6.44 ± 0.08 µg/mL and against the chloroquine-resistant strain with an IC50 of 7.53 ± 0.22 µg/mL. The ethanol extract demonstrated suppressive activity in vivo with reduction rates of 87.69%, 86.79%, and 81.08% at doses of 500 mg/kg, 250 mg/kg, and 125 mg/kg, respectively; and curative activity in vivo with reduction rates of 80%, 78.5%, and 77.5% at doses of 500 mg/kg, 250 mg/kg, and 125 mg/kg, respectively. The number of white blood cells in the negative control (44.55 ± 5.02 103/µL) was higher compared to the other groups. As for the red blood cells, we observed a massive destruction of the latter in the infected and untreated group (5.82 ± 1.50 106/µL) compared to the infected and ethanol extract-treated groups (8.74 ± 1.57 106/µL for 500 mg/kg, 7.54 ± 1.77 106/µL for 250 mg/kg, and 8.9 ± 1.50 106/µL for 125 mg/kg).ConclusionThis study provides scientific data on the use of E. sigmoidea by the local population for the treatment of malaria. It shows that E. sigmoidea has antiplasmodial activity, and we also see that there are differences between the parameters that we have in the treated groups and those of the untreated group. However, toxicity tests are necessary to assess its safety.

Antiplasmodial Activity and Phytochemical Evaluation of the Stems of Albizia coriaria and Ficus sur

Background: Malaria continues to cause havoc on various populations because of the high mortality and economic burden associated with the disease. Progress made in the therapeutics of the disease is threatened by the emerging parasite resistance to currently used first line treatment drugs. This has prompted the search for new, effective, and safe antimalarial agents. The use of traditional medicine in the treatment of various types of diseases including malaria is a regular practice seen with many cultures in Ghana. The stems of Albizia coriaria Welw ex. Oliver and Ficus sur Forssk are such plants used with little evidence about their in vivo efficacy. Aim: This study therefore aimed to assess the in vivo antiplasmodial potential, and the acute toxicity of the hydroethanolic stem extract of Albizia coriaria and Ficus sur. Method: Qualitative phytochemical screening was done on the powdered plant material using standard methods. Acute toxicity was carried out according to OECD guidelines using the Limit test. In vivo antiplasmodial activity of the hydroethanolic extract was assessed using the Peter’s 4-day suppressive and Rane’s curative test. Results: The 70% ethanol extract was safe with the lethal dose above 3000 mg/kg. All the extracts significantly (P &lt; 0.05) suppressed parasitaemia in the Peter’s suppressive and Rane’s curative test with Albizia coriaria producing the highest chemotherapeutic activity of 68.89 and 61.46% in the suppressive and curative test respectively. That of F. sur was less than 50% in both assays. Artesunate reference drug recorded over 80% suppression in the curative test but lesser activity in the suppression assay compared to A. coriaria. Several plant metabolites including terpenoids, flavonoids and coumarins were found in both plant samples. Conclusion: Albizia coriaria and Ficus sur 70% ethanol extract showed considerable antiplasmoidal activity and were found to be non-toxic in acute toxicity study, thus justifying their safe use in the treatment of malaria as suggested by folklore medicine.

Evaluation of the antiplasmodial activity of &lt;i&gt;Curcuma longa&lt;/i&gt; (turmeric - Zingiberaceae) on &lt;i&gt;Plasmodium berghei&lt;/i&gt; in laboratory mice.

Malaria is a leading cause of morbidity and mortality worldwide, especially in developing countries and in sub-Saharan Africa where most malaria cases and deaths occur. The resistance of malaria parasites to most anti-malaria drugs, coupled with the high cost and the toxic effects of some drugs has posed a challenge for the search of new effective anti-malarial compounds of low cost. The study aims to determine the antiplasmodial activity of Curcuma longa against Plasmodium berghei in rodents. A total of 110 Swiss albino mice weighing 18-30 grams were used for the study: 35 for the toxicity test and 75 for the antimalarial study. For each test, 25 mice were inoculated with drug-sensitive Nk65 Plasmodium berghei and divided into five groups of five animals each and each group was administered one of the following: 120mg/kg of ethanol extract, 120mg/kg water extract, 120mg/kg nHexane extracts of C. longa, 1.2mg/kg of pyrimethamine or 5mg/kg of Chloroquine (positive control) and 0.2mls of normal saline (negative control). The lethal dose concentration was above 1500mg/kg and the extracts showed significant (P&lt;0.05) antimalarial activity with the highest percentage inhibition (67.49%) recorded in the group treated with ethanol in the curative test, followed by the group given water in the suppressive test with (65.03%) and nHexane in the prophylactic test with percentage inhibition of 64.98%. There was a slight difference in the antimalarial activities of the extracts of different solvents which all had lower activities compared with the standard drugs (Chloroquine administered at 5mg/kg or pyrimethamine, 1.2mg/kg/day) but no total clearance of the parasite was recorded. C. longa possesses considerable antiplasmodial activity, which can be exploited in malaria therapy.

Antimalarial Efficacy of Ethanol Extract of Bridelia micrantha Stem Bark against Plasmodium berghei-Infected Mice.

The spread of drug resistance is a significant issue, particularly in endemic countries with limited resources. The aim of this study was to evaluate antimalarial and antioxidant activity of B. micrantha in order to justify its use in traditional medicine. Evaluation of the in vivo antimalarial activity of B. micrantha was carried out according to the model of the suppressive and curative test of Peters' over 4 days in infected Swiss albino mice. Antioxidant parameters and stress were measured after intraperitoneal administration of 1 × 107 infected red blood cells. At doses of 150 mg/kg, 300 mg/kg, and 600 mg/kg, administration of B. micrantha substantially produced suppression of P. berghei infection by 67.75%, 73.46%, and 78.99%, respectively, while 84.64% of the untreated group (1% DMSO) had suppression from chloroquine. The curative test significantly decreased the levels of parasitaemia and death in the treated groups. Furthermore, after B. micrantha extract was given to infected mice, a noteworthy increase in total protein, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) was observed. On the other hand, hepatic catalase (CAT) and superoxide dismutase (SOD) productions were considerably greater than that of the healthy control. Mice had considerably lower levels of nonenzymatic antioxidant markers such as glutathione, NO, and MDA showing that the liver was protected. The infected groups responded favorably to the ethanol extract of B. micrantha. This result justifies investigation for its use in Cameroon.

Antiplasmodial activity and toxicity of the leaves, stem and roots of Parinari robusta Oliv [CHRYSOBALANACEAE] in animal model

Malaria continues to wreak havoc on various populations as a result of the mortality and economic burden associated with the disease. Progress made in the therapeutics of the disease is threatened by the emerging parasite resistance to currently used first line treatment drugs. This has prompted the search for new, effective, and safe antimalarial agents. Parinari robusta is one plant in use with inadequate evidence about its efficacy. This study therefore aimed to assess the in vivo and in vitro antimalarial potential, and the safety of the leaves, stem and roots of the plant. Acute toxicity was carried out according to OECD guidelines. In vivo antimalarial activity of the hydroethanolic extracts were assessed using the Peter's 4-day suppressive and Rane's curative tests. In vitro antiplasmodial activity of the hydroethanolic crude extracts were evaluated using the SYBR Green I fluorescence assay on the chloroquine sensitive (3D7) and chloroquine resistant (Dd2) strains of P. falciparum. P. robusta was safe with the lethal dose above 3000 mg/kg. All the extracts significantly (p < 0.001) suppressed parasitaemia in the Peter's suppressive and Rane's curative test in a dose dependent manner. The extracts showed highly to weakly active in vitro antiplasmodial activity with an IC50 between 2.629 μg/ml to 30.320 μg/ml against 3D7 and Dd2 strain of P. falciparum. Leaf and stem extract gave the most superior activity against the Dd2 and 3D7 P. falciparum strains. The findings of this study provide scientific evidence supporting the traditional use of P. robusta in the treatment of malaria.

Assessment of antimalarial activity of crude extract of Chan-Ta-Lee-La and Pra-Sa-Chan-Dang formulations and their plant ingredients for new drug candidates of malaria treatment: In vitro and in vivo experiments.

The emergence and spread of antimalarial drug resistance have become a significant problem worldwide. The search for natural products to develop novel antimalarial drugs is challenging. Therefore, this study aimed to assess the antimalarial and toxicological effects of Chan-Ta-Lee-La (CTLL) and Pra-Sa-Chan-Dang (PSCD) formulations and their plant ingredients. The crude extracts of CTLL and PSCD formulations and their plant ingredients were evaluated for in vitro antimalarial activity using Plasmodium lactate dehydrogenase enzyme and toxicity to Vero and HepG2 cells using the tetrazolium salt method. An extract from the CTLL and PSCD formulations exhibiting the highest selectivity index value was selected for further investigation using Peter's 4-day suppressive test, curative test, prophylactic test, and acute oral toxicity in mice. The phytochemical constituents were characterized using gas chromatography-mass spectrometry (GC-MS). Results showed that ethanolic extracts of CTLL and PSCD formulations possessed high antimalarial activity (half maximal inhibitory concentration = 4.88, and 4.19 g/mL, respectively) with low cytotoxicity. Ethanolic extracts of the CTLL and PSCD formulations demonstrated a significant dose-dependent decrease in parasitemia in mice. The ethanolic CTLL extract showed the greatest suppressive effect after 4 days of suppressive (89.80%) and curative (35.94%) testing at a dose of 600 mg/kg. Moreover, ethanolic PSCD extract showed the highest suppressive effect in the prophylactic test (65.82%) at a dose of 600 mg/kg. There was no acute toxicity in mice treated with ethanolic CTLL and PSCD extracts at 2,000 mg/kg bodyweight. GC-MS analysis revealed that the most abundant compounds in the ethanolic CTLL extract were linderol, isoborneol, eudesmol, linoleic acid, and oleic acid, whereas ethyl 4-methoxycinnamate was the most commonly found compound in the ethanolic PSCD extract, followed by 3-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-4H-chromen-4-one, flamenol, oleic acid amide, linoleic acid, and oleic acid. In conclusions, ethanolic CTLL and PSCD extracts exhibited high antimalarial efficacy in vitro. The ethanolic CTLL extract at a dose of 600 mg/kg exhibited the highest antimalarial activity in the 4-day suppressive and curative tests, whereas the ethanolic PSCD extract at a dose of 600 mg/kg showed the highest antimalarial activity in the prophylactic test.

The potential of Trichoderma asperellum organic extract and its emulsion to inhibit cocoa ( Theobroma cacao L.) black pod disease and induce biochemical defenses against Phytophthora megakarya

This work aimed to evaluate the potential of Trichoderma asperellum organic extract and its emulsion to control cocoa black pod disease caused by Phytophthora megakarya. Organic extract was obtained after fermentation of T. asperellum and its emulsion prepared by emulsification. The in vitro antimicrobial assays of organic extract and its emulsion were evaluated and the in situ tests were carried out on detached cocoa pods. T. asperellum inhibited the mycelia growth of P. megakarya at the rates of 52% and 100%, respectively, on dual culture and the cellophane plate. This antagonist produced lytic enzymes such as cellulase, amylase, lipase and protease. The organic extract contained alkaloid, flavonoid and phenol compounds. The emulsion obtained was stable. At 100 μg · ml -1, the extract and its formulation completely inhibited the mycelial growth of P. megakarya. Similarly, when infected detached cocoa pods were sprayed with extract or emulsion, there was a significant reduction of necrosis both for healing and prevention with the latter being the most efficient. For the preventive tests, the total inhibition was recorded at 3000 μg · ml -1 and 1000 μg · ml -1, respectively, with crude organic extract and its emulsion· For curative tests, total inhibition was obtained at 4000 μg · ml -1 and 3000 μg · ml -1, respectively, for preventive and curative tests. There was a significant and positive correlation between the content of biochemical markers and the reduction of necrosis on cocoa pods after treatment with the extract or its formulation. T. asperellum organic extract emulsion could be used as an alternative in the bio- protection of cocoa black pods disease.

The Effect of Ethanol Extract of Pearl Grass (Hedyotis corymbosa (L.) Lamk) on TNF-α and IL-10 Levels in Mice Infected with Plasmodium berghei

Pearl grass (Hedyotis corymbose, (L.) Lamk) has been reported to have antimalarial activity against Plasmodium falciparum and Plasmodium berghei because of its chemical contents as well as anti-inflammatory activity. This current study aimed to analyse the effect of ethanolic extract of pearl grass (EEHC) on the serum level of TNF-α and IL-10 in mice infected with P. berghei. Fifty male BALB/c mice were infected with 1×106 P. berghei-infected erythrocytes from donor mice, and then were randomly divided into five groups. Each group contained 10 mice. Group 1 was a positive control group, and treated with 187.2 mg/Kg BW antimalaria drug of dihydroartemisinin piperaquine (DHP). Group 2 was a negative control group without any additional drugs. Group 3, 4, and 5 were treated with 250, 300, and 350 mg/Kg BW of EEHC, respectively. A curative test of EEHC was started on day three post-infection, followed by daily treatments of two hundred microliters of EEHC for four consecutive days. Parasitaemia was observed on day five post-treatment on Giemsa-stained tail blood smears followed by cardiac puncture to obtain sera prior to TNF-α and IL-10 measurement by ELISA. The findings showed that higher doses of EEHC reduced parasitemia, which increases their therapeutic impact. Serum level of TNF-α was lower in mice treated with higher doses of EEHC, while IL-10 was vice versa. Serum level of TNF-α was correlated with percentage parasitemia, whereas IL-10 was not. These findings demonstrated EEHC’s anti-inflammatory effect against malaria in mice, suggesting that it may be developed as an antimalarial drug in the future.

A Study on Justicia flava (Forssk.) Vahl.: Pharmacognostic Characterization and Antiplasmodial and Anti-Inflammatory Properties of the Leaves

Justiciaflava (Acanthaceae) is utilized in folk medicine for treating malaria, inflammatory conditions, and respiratory infections. In this study, the antiplasmodial and anti-inflammatory activities of the 70% hydroalcoholic leaf extract of J. flava (JFE) were investigated. The antiplasmodial activity was assessed by the suppressive test and Rane’s curative test. The carrageenan-induced paw oedema assay in chicks was used to assess the anti-inflammatory activity. In Rane’s curative test, JFE significantly suppressed the parasitaemia level ( p &lt; 0.0001) by 56.85%, 63.85%, and 77.85% at 30, 100, and 300 mg·kg−1, respectively. The highest suppression of parasitaemia in the suppressive test was 51.31% at 300 mg·kg−1. The extract prolonged the survival time of infected mice significantly and prevented weight loss and hypothermia which are cardinal signs of P. berghei-induced infection. JFE inhibited foot oedema in chicks with a maximum percentage inhibition of 54.00 ± 5.20%. Pharmacognostic characterization of J. flava revealed it to have simple, petiolate, oppositely arranged leaves which are broadly lanceolate in shape with entire to slightly crenate margins. Microscopy of the leaf showed wavy-walled epidermal cells, diallelocytic stomata, abundant clothing and secretory trichomes, pitted vessels, collateral conjoint vascular bundles, cystoliths, and prismatic calcium oxalate crystals. Flavonoids, tannins, phytosterols, triterpenoids, coumarins, alkaloids, and saponins were detected in the plant. This study has provided important parameters for the correct identification of J. flava and given the scientific credence to its antimalarial and anti-inflammatory effects in traditional medicine. J. flava is a potential source of new antimalarial and anti-inflammatory compounds.

Therapeutic Potentials of Azadirachta indica and Ocimum gratissimum, and their Synagistic Effects in Treatment of Plasmodium berghei Infected Albino Mice

Antimalarial resistance is a major challenge for effective control of malaria. This triggered the need to monitor the efficacy of Azadirachta indica and Ocimum gratissimum in the disease management. The present study compared antimalarial activities of the leaf extracts of the individual plants and evaluated their combined effects on malaria infected mice. The leaves of the different plants were extracted with absolute ethanol (BDL 95%) for the test. Clean albino mice were experimentally infected intraperitoneally with chloroquine-sensitive Plasmodium berghei Nk65 strain. Parasitaemia level was determined before parasite inoculation and at 24 hours post treatment period. Efficacy of the leaf extracts was tested on the infected mice using Peter’s 4-days suppressive and curative tests, and secondary biological assessment procedures.The lethal median dose (LD50) recorded for neem and clove basil leaf extracts were 31.62 and 1246.9 mg/kg body weight, respectively. Infected mice treated with leaf extracts of the plants and their combinations produced significant dose- dependent activity against the parasite (P&lt;0.05). Highest reduction of parasitaemia was observed on day 4. Maximum parasitaemia reduction (78.65%) was attained with 30mg/kg of the combination of the extracts on the 7th day. These observations indicate better anti-malarial activity of the combination therapy as compared with the individual extracts of the plants, and also show their good antimalarial potentials.

Antimalarial Effects of Ethanolic Leaf Extracts of Azadirachta indica and Ocimum gratissimum, and Their Histologic Effects on Some Organs (Liver, Kidney and Heart) of Plasmodium berghei Infected Albino Mice

Azadirachta indica (Neem) and Ociumum gratissimum (clove Basil) have long been employed locally for the management of malaria. The present study compared antimalaria activities of the ethanolic leaf extracts of the individual plants, and assessed their combined effects on some organs of malaria-infected mice, at the Parasitology and Histopathology units, Federal Medical Centre (FMC), Owerri, from January to March, 2021. The leaves of the different plants were extracted with absolute ethanol (BDL 95%) for the test. Clean albino mice were experimentally infected intraperitoneally with chloroquine-sensitive Plasmodium berghei NK65 strain. Parasitaemia level was determined before parasite inoculation and at 24 hours post treatment period. Histopathological study on the liver, kidney, and heart was carried out using the Paraffin Setions method. Extracts of the leaves were administered orally, while chloroquine administration was intramuscular. The efficacy of the leaf extracts was tested on the P. berghei infected albino mice using the 4-day curative test. The lethal median dose (LD50) recorded for neem and clove basil leaf extracts were 31.62 and 1246.9 mg/kg body weight, respectively. Significant activity against the parasite was produced by infected mice treated with extracts of A. indica and O. gratissimum, and their combinations throughout the treatment period (P&lt;.05). Highest reduction of parasitaemia was observed on day 4. Maximum parasitaemia reduction (78.65%) was attained with 30mg/kg of the combined extracts on the 7th day. Mild pathological lesions were observed in mice treated with A. indica leaf extract. These observations indicate better anti-malaria activity of the combination therapy as compared with the individual extracts of A. indica and O. grassimum, and indicate good antimalarial and protective roles of the plant extracts on the parasitized mice at large, as it slows down development of resistance.