Antibacterial activities of methanol extracts from Alchornea cordifolia and four other Cameroonian plants against MDR phenotypes

AbstractObjectivesMultidrug-resistant (MDR) bacterial infections, especially those caused by Gram-negative phenotypes, have emerged as one of the major health concerns worldwide. In the present study, we investigated the antibacterial activity of methanol extracts from five Cameroonian medicinal plants (Alchornea cordifolia, Eremomastax speciosa, Laportea aestuans, Pennisetum purpureum and Spathodea campanulata) against 15 Gram-negative bacteria that included MDR phenotypes.MethodsThe broth microdilution method was used to determine the minimal inhibitory concentrations (MIC) and the minimal bactericidal concentrations (MBC) of all of the samples. Standard phytochemical methods were used for a preliminary phytochemical screening of the plant extracts.ResultsPhytochemical analysis showed the presence of polyphenols, tannins, triterpenes and sterols in all of the studied extracts. Other chemical classes of secondary metabolites were selectively identified. The best antibacterial activities (MICs ranges of 64–1024 μg/mL) obtained against the 15 tested bacteria were found in extracts of leaves (93.3%), bark (86.7%) and roots (80%) of A. cordifolia as well as extracts of L. aestuans (86.7%) and P. purpureum (66.7%). The lowest MIC value of 64 μg/mL was recorded for the A. cordifolia bark extract against Pseudomonas aeruginosa PA01.ConclusionsThe findings of this study provide deep insights into the possible use of the studied plants, especially A. cordifolia and L. aestuans, for the control of Gram-negative bacterial infections, especially against MDR species

Cytotoxicity of Elaoephorbia drupifera and other Cameroonian medicinal plants against drug sensitive and multidrug resistant cancer cells

BACKGROUND: Multidrug resistance (MDR) is a major hurdle for cancer treatment worldwide and accounts for chemotherapy failure in over 90% of patients with metastatic cancer. Evidence of the cytotoxicity of Cameroonian plants against cancer cell lines including MDR phenotypes is been intensively and progressively provided. The present work was therefore designed to evaluate the cytotoxicity of the methanol extracts of twenty-two Cameroonian medicinal plants against sensitive and MDR cancer cell lines. METHODS: The methanol maceration was used to obtain the crude plant extracts whilst the cytotoxicity of the studied extracts was determined using a resazurin reduction assay. RESULTS: A preliminary assay on leukemia CCRF-CEM cells at 40 μg/mL shows that six of the twenty plant extract were able to enhance less than 50% of the growth proliferation of CCRF-CEM cells. These include Crinum zeylanicum (32.22%), Entada abyssinica (34.67%), Elaoephorbia drupifera (35.05%), Dioscorea bulbifera (45.88%), Eremomastax speciosa (46.07%) and Polistigma thonningii (45.11%). Among these six plants, E. drupifera showed the best activity with IC(50) values below or around 30 μg/mL against the nine tested cancer cell lines. The lowest IC(50) value of 8.40 μg/mL was recorded with the extract of E. drupifera against MDA-MB231 breast cancer cell line. The IC(50) values below 10 μg/mL were recorded with the extracts of E. drupifera against MDA-MB231 breast cancer cells, C. zeylanicum against HCT116 p53(+)/(+) and HCT116p53(-)/(-) colon cancer cells and E. abyssinica against HCT116 p53(+)/(+) cells. CONCLUSION: The results of the present study provide evidence of the cytotoxic potential of some Cameroonian medicinal plants and a baseline information for the potential use of Elaoephorbia drupifera in the treatment of sensitive and drug-resistant cancer cell lines

Evaluation of four Cameroonian medicinal plants for anticancer, antigonorrheal and antireverse transcriptase activities

Methanol extracts from the leaves, bark and roots of four Cameroonian medicinal plants, Bersama engleriana, Cupressus lusitanica, Vitellaria paradoxa and Guibourtia tessmannii were tested for their in vitro cytotoxicity, antigonorrheal and antireverse transcriptase activities. The XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt) assay, the dilution method and reverse transcriptase (RT) assay were used for the investigations. Preliminary phytochemical analysis of the extracts was also conducted using standard methods. Results showed that all extracts contained compounds belonging to the classes of phenols and terpenoids. They were also able to reduce in dose dependent manner, the proliferation of the cancer THP-1, DU145, HeLa, MCF-7, HepG2 and the normal Vero cells. IC50 values below 30 μg/ml were noted with extract from the three parts of B. engleriana on at least two of the five studied cancer cell lines, the lowest value of 5.9 μg/ml being obtained with sample from the bark. IC50 values below 30 μg/ml were also recorded with extracts from the leaves (on HeLa cells) and bark (on MCF-7) of G. tessmanii, and that from the bark of C. lusitanica on MCF-7. Extracts from B. engleriana and those from the bark of V. paradoxa gave the minimal inhibitory concentrations (MIC) values below 100 μg/ml on most of the 10 tested Nesseria gonorrhoeae strains. Extracts from B. engleriana also inhibited more than 80% the activity of the Human Immuno-deficiency Virus (HIV) enzyme. Finally, the results of the present study provide baseline information for the use of B. engleriana, C. lusitanica, G. tessmanii, V. paradoxa.http://www.elsevier.com/locate/etapnf201

Multidrug resistant bacteria are sensitive to Euphorbia prostrata and six others Cameroonian medicinal plants extracts

Abstract Background Multidrug resistant (MDR) bacteria are responsible for therapeutic failure and there is an urgent need for novels compounds efficient on them. Methods Eleven methanol extracts from seven Cameroonian medicinal plants were tested for their antibacterial activity using broth micro-dilution method against 36 MDR bacterial strains including Escherichia coli, Enterobacter aerogenes, Enterobacter cloacae, Klebsiella pneumoniae, Providencia stuartii, Pseudomonas aeruginosa and Staphylococcus aureus. Results Euphorbia prostrata extract was found active against all the 36 tested bacteria including Gram-negative phenotypes over-expressing efflux pumps such as P. aeruginosa PA124, E. aerogenes CM64 and E. coli AG102. E. prostrata had minimal inhibitory concentrations values between 128 and 256 µg/mL on 55.55% of the studied microorganisms. Other plants extract displayed selective antibacterial activity. Conclusions Results obtained in this study highlight the antibacterial potential of the tested plants and the possible use of E. prostrata to combat bacterial infections including MDR phenotypes

Antibacterial activities of the methanol extracts of Albizia adianthifolia, Alchornea laxiflora, Laportea ovalifolia and three other Cameroonian plants against multi-drug resistant Gram-negative bacteria

In the last 10 years, resistance in Gram-negative bacteria has been increasing. The present study was designed to evaluate the in vitro antibacterial activities of the methanol extracts of six Cameroonian medicinal plants Albizia adianthifolia, Alchornea laxiflora, Boerhavia diffusa, Combretum hispidum, Laportea ovalifolia and Scoparia dulcis against a panel of 15 multidrug resistant Gram-negative bacterial strains. The broth microdilution was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the extracts. The preliminary phytochemical screening of the extracts was conducted according to the reference qualitative phytochemical methods. Results showed that all extracts contained compounds belonging to the classes of polyphenols and triterpenes, other classes of chemicals being selectively distributed. The best antibacterial activities were recorded with bark and root extracts of A. adianthifolia as well as with L. ovalifolia extract, with MIC values ranging from 64 to 1024 μg/mL on 93.3% of the fifteen tested bacteria. The lowest MIC value of 64 μg/mL was recorded with A. laxiflora bark extract against Enterobacter aerogenes EA289. Finally, the results of this study provide evidence of the antibacterial activity of the tested plants and suggest their possible use in the control of multidrug resistant phenotypes

Haematological Features and Urologic Pathologies of Diabetic Subjects at Bafoussam Regional Hospital: A Cross-Sectional Study

Background. Diabetes mellitus is at the origin of long-term complications. Objective. This study is aimed at assessing the haematological features and urologic pathologies of diabetic individuals at Bafoussam Regional Hospital. Methods. This was a cross-sectional study conducted from August 2018 to May 2019 in Bafoussam Regional Hospital, West Cameroon. A structured questionnaire was used to gather sociodemographic data. A trained nurse measured the physical and clinical features. Fasting plasma glucose was determined using the glucose meter Accu-Chek Active system. The full blood count (FBC) was carried out using Automatic full Blood Counter, and the CD4, CD3, and CD8 T-cell counts were determined using the flow cytometry method. Results. There were 455 diabetic patients, and 50 nondiabetic patients were included. The mean age of diabetic patients (56.94±14.33 years) was higher compared to that of nondiabetic individuals (34.76±14.35 years) (p<0.001). There was a significant relationship between married individuals (χ2=79.19, p<0.001, and df=4), housewife and retired (χ2=1117.38, p<0.001, and df=37), old age (40 years and above) (χ2=79.11, p<0.001, and df=3), and diabetes status. Diabetic patients had an odds of 5.52 to experience a urinary urge as compared to the controls (p<0.001, 95% CI=2.15-14.22). The majority of haematological parameters were negatively but not significantly correlated with diabetes. Binary logistic regression shows that MCV (r=−0.251, OR=0.778, and 95% CI=0.617–0.983; p=0.035) and RDW-CV (r=−0.477, OR=0.620, and 95% CI=0.454–0.848; p=0.003) negatively influence the probability of having diabetes. RDW-SD (r=0.135, OR=1.144, and 95% CI=1.014–1.291; p=0.029) positively influences the probability of having diabetes. Conclusion. This study revealed a significant haematological and urological profile difference according to diabetes status. Research and interventions targeted at diabetic population could help close gaps in diabetes complications

Cytotoxicity of the methanol extracts of Elephantopus mollis, Kalanchoe crenata and 4 other Cameroonian medicinal plants towards human carcinoma cells

Abstract Background Cancer still constitutes one of the major health concerns globally, causing serious threats on patients, their families, and the healthcare system. Methods In this study, the cytotoxicity of the methanol extract of Elephantopus mollis whole plant (EMW), Enantia chlorantha bark (ECB), Kalanchoe crenata leaves (KCL), Lophira alata bark (LAB), Millettia macrophylla leaves (MML) and Phragmanthera capitata leaves (PCL) towards five human solid cancer cell lines and normal CRL2120 fibroblasts, was evaluated. Extracts were subjected to qualitative chemical screening of their secondary metabolite contents using standard methods. The cytotoxicity of samples was evaluated using neutral red uptake (NR) assay meanwhile caspase activation was detected by caspase-Glo assay. Flow cytometry was used to analyze the cell cycle distribution and the mitochondrial membrane potential (MMP) whilst spectrophotometry was used to measure the levels of reactive oxygen species (ROS). Results Phytochemical analysis revealed the presence of polyphenols, triterpenes and sterols in all extracts. The IC50 values of the best samples ranged from 3.29 μg/mL (towards DLD-1 colorectal adenocarcinoma cells) to 24.38 μg/mL (against small lung cancer A549 cells) for EMW, from 2.33 μg/mL (mesothelioma SPC212 cells) to 28.96 μg/mL (HepG2 hepatocarcinoma) for KCL, and from 0.04 μg/mL (towards SPC212 cells) to 0.55 μg/mL (towards A549 cells) for doxorubicin. EMW induced apoptosis in MCF-7 cells mediated by MMP loss and increased ROS production whilst KCL induced apoptosis via ROS production. Conclusion This study provides evidences of the cytotoxicity of the tested plant extract and highlights the good activity of Elephantopus mollis and Kalanchoe crenata. They deserve more exploration to develop novel cytotoxic drugs

Antistaphylococcal Activity of Extracts, Fractions, and Compounds of Acacia polyacantha Wild (Fabaceae)

Acacia polyacantha is a medicinal plant traditionally used to treat livestock diseases and gastrointestinal infections; our study was undertaken to evaluate the antistaphylococcal activities of the methanolic leaf, bark, and root extracts, fractions, and compounds from Acacia polyacantha against a panel of 14 multidrug-resistant Staphylococcus bacterial strains overexpressing efflux pumps. The study was also extended to investigate two possible modes of action, that is, influence on bacterial growth kinetics and influence on proton-ATPase pumps, of the most active compound against a reference strain. Materials and Methods. The crude extracts after extraction were subjected to column chromatography. Antibacterial assays of extracts, fractions, and compounds alone and in the presence of efflux pump inhibitors were carried out using the broth microdilution method and the study of two mechanisms of action achieved by standard methods with the most active compound. Results. The phytochemical study of Acacia polyacantha leaves leads to the isolation of stigmasterol (1), β-amyrin (2), 3-O-methyl-D-chiro-inositol (3), epicatechin (4), quercetin-3-O-galactoside (5), 3-O-[β-D-xylopyranosyl-(1 ⟶ 4)-β-D-galactopyranosyl]-oleanolic acid (6), 3-O-[β-galactopyranosyl-(1⟶ 4)-β-D-galactopyranosyl]-oleanolic acid (7) and that of leaves lead to the isolation of lupeol (8) 2,3-dihydroxypropyltetracosanoate (9), and methyl-gallate (10). Leaf, root, and bark extracts inhibited 92.85% (13/14), 92.85% (13/14), and 71.43 % (10/14) of the tested bacteria strains, respectively, with minimum inhibitory concentration (MIC) varying between 16 and 1024 μg/mL. Fractions exhibited better activities compared to those of their extracts of origin, as their MICs ranged from 16 to 512 μg/mL, with fractions from leaves being more active than those obtained from barks. Compounds had varying activities; MICs varied from 16 to 512 μg/mL with compound 4 presenting the best activity as MICs ≤100 μg/mL were obtained against 11 of the tested bacteria. The activities of extracts, fractions, and compounds were improved in the presence of carbonyl cyanide m-chlorophenylhydrazone (CCCP) as an efflux pump inhibitor to as much as >128 folds. Meanwhile, in the presence of chlorpromazine as an efflux pump inhibitor, only the activity of compound 10 was improved on 10 of the tested bacteria strains. Compound 4 prolonged the lag phase of the growth kinetic in a concentration-dependent manner and equally inhibited the proton-ATPase pumps of the tested bacteria strains. Conclusion. The present study demonstrates the antistaphylococcal potential of Acacia polyacantha and its constituents to combat bacterial infections alone or in combination with efflux pump inhibitors

Antimicrobial activity of the crude extracts and five flavonoids from the twigs of Dorstenia barteri (Moraceae)

Please refer to abstract in articl

An Efflux Pumps Inhibitor Significantly Improved the Antibacterial Activity of Botanicals from Plectranthus glandulosus towards MDR Phenotypes

Bacterial multidrug resistance causes many therapeutic failures, making it more difficult to fight against bacterial diseases. This study aimed to investigate the antibacterial activity of extract, fractions, and phytochemicals from Plectranthus glandulosus (Lamiaceae) against multidrug-resistant (MDR) Gram-negative phenotypes expressing efflux pumps. The crude extract after extraction was subjected to column chromatography, and the structures of the isolated compounds were determined using spectrometric and spectroscopic techniques. Antibacterial assays of samples alone and in the presence of an efflux pump inhibitor (phenylalanine-arginine β-naphthylamide, PAβN) were carried out using the broth microdilution method. The phytochemical study of P. glandulosus plant extract afforded seven major fractions (A–G) which lead to the isolation of seventeen known compounds. The ethanol extract of P. glandulosus was not active at up to 1024 μg/mL, whereas its fractions showed MICs varying from 32 to 512 μg/mL on the studied bacteria. Fraction C of P. glandulosus showed the lowest MIC (32 μg/mL) on E. coli ATCC8739 strain. Fraction D presented the highest activity spectrum by inhibiting the growth of 90% (9/10) of the studied bacteria. The presence of PAβN has improved the activity of extract and all fractions. Overall, the tested phytochemicals showed low activity against the studied bacteria. The overall results obtained in this study show that some fractions from P. glandulosus, mainly fractions C and D, should be investigated more for their possible use to fight against MDR bacteria