scholarly journals Antisickling and Antibacterial Activities of Anthocleista schweinfurthii Gilg. (Gentianaceae) from Non-human Primates Pharmacopoeia in Democratic Republic of the Congo

Author(s):  
Samy Ngunde-te-Ngunde ◽  
Emmanuel Moke Lengbiye ◽  
Tshidibi Dipa Joseph ◽  
Kengo Velantia Franck ◽  
Ruphin D. Djolu ◽  
...  

The aim of the present study was to evaluate the Chemical composition and bioactivity of Anthocleista schweinfurthii Gilg (Gentianaceae) fruits, leaves, root bark and stem bark extracts against Sickle cell disease (SCD) and associated bacteria. The antisickling and antibacterial activities were carried out using Emmel and micro-dilution methods respectively. The results revealed that the fruits, leaves, root bark and stem bark extracts  of A. schweinfurthii contains various secondary metabolites such as the alkaloids, saponins, total polyphenols, flavonoids, tannins, anthocyanis, leuco-anthocyanins and quinones.  The ethyl acetate and methanol extracts displayed antisickling activity. While, the antibacterial activity of different plant extracts tested was weak toward tested bacterial strains (CMI ≥125μg/mL). The antibacterial activity can be improved by bio-guided fractionation of the n-hexane, ethyl acetate or methanol soluble fraction. This study provides for the first time a scientific basis for the in vitro antisickling activity of A. schweinfurthii.

2021 ◽  
Vol 17 ◽  
Author(s):  
Lijuan Zhai ◽  
Lili He ◽  
Yuanbai Liu ◽  
Ko Ko Myo ◽  
Zafar Iqbal ◽  
...  

Background: Mononcyclic β-lactams are regarded as the most resistant class of β-lactams against a series of β-lactamases though possess limited antibacterial activity. Aztreonam being the first clinically approved monobactam needs broad-spectrum efficacy through structural modification. Objective: We strive to synthesize a number of monocyclic β-lactams by varying the substituents at N1, C3 and C4 positions of azetidinone ring and study the antimicrobial effect on variable bacterial strains. Methods: Seven new monobactam derivatives 23a-g, containing substituted-amidine moieties linked to the azetidinone ring via thiazole linker, were synthesized through multistep synthesis. The final compounds were investigated for their in vitro antibacterial activities using broth microdilution method, against ten bacterial strains of clinical interest. The minimum inhibitory concentrations (MICs) of newly synthesized derivatives were compared with aztreonam, ceftazidime and meropenem, existing clinical antibiotics. Results: All compounds 23a-g showed higher antibacterial activities (MIC 0.25 µg/mL to 64 µg/mL) against tested strains as compared to aztreonam (MIC 16 µg/mL to >64 µg/mL) and ceftazidime (MIC >64 µg/mL). However all compounds, except 23d, exhibited lower antibacterial activity against all tested bacterial strains as compared to meropenem. Conclusion: Compound 23d showed comparable or improved antibacterial activity (MIC 0.25 µg/mL to 2 µg/mL) to meropenem (MIC 1 µg/mL to 2 µg/mL) in case of seven bacterial species. Therefore, compound 23d may be valuable lead target for further investigations against multi-drug resistant Gram-negative bacteria.


2016 ◽  
Vol 11 (9) ◽  
pp. 1934578X1601100
Author(s):  
Sakon Monggoot ◽  
Jariya Burawat ◽  
Patcharee Pripdeevech

A total of 17 endophytic fungal isolates were obtained from the leaves of Mentha cordifolia Opiz (Lamiaceae). Seven isolates were identified to the level of genus by using taxonomically relevant morphological traits. Colletotrichum and Phomopsis species were dominant among these strains. All strains were separated from M. cordifolia leaf for the first time. The ethyl acetate extracts of all endophytic fungi were tested for antibacterial activity against Salmonella typhimurium TISTR1166 and Pseudomonas aeruginosa TISTR781. Most endophytes exhibited antibacterial activity. Ustilago sp. MFLUCC15-1024 presented the highest inhibition zone diameter with a MIC of 31.25 μg/mL against the tested pathogens. The chemical composition of the ethyl acetate extract of this strain was investigated using gas chromatography-mass spectrometry. Twenty-one components were identified. 2-Phenylethanol (38.7%), E-ligustilide (12.4%), α-eudesmol (10.2%), β-vetivone (4.6%), β-ylangene (3.7%) and verbanol (3.4%) were the major components of the extract. The strong antibacterial activity of Ustilago sp. MFLUCC15-1024 ethyl acetate extract may be attributed to the presence of a high concentration of bioactive compounds including phenyl ethyl alcohol, E-ligustilide and α-eudesmol. The results indicate that there is high diversity of endophytic fungi in M. cordifolia leaf, and that Ustilago sp. MFLUCC15-1024 strain could be an excellent resource of natural antibacterial compounds.


2015 ◽  
Vol 10 (6) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Dragoljub L. Miladinović ◽  
Budimir S. Ilić ◽  
Branislava D. Kocić

The chemical composition and antibacterial activity of Nepeta nuda (Lamiaceae) essential oil were examined, as well as the association between it and standard antibiotics: tetracycline and streptomycin. The antibacterial activities of 1,8-cineole, the main constituent of N. nuda oil, individually and in combination with standard antibiotics were also determined. The interactions of the essential oil and 1,8-cineole with antibiotics toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemoinformatics methods. Oxygenated monoterpenes were the most abundant compound class in the oil (57.8%), with 1,8-cineole (46.0%) as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antibiotics. The combinations N. nuda oil-antibiotic and 1,8-cineole-antibiotic produced a predominantly antagonistic interactions. Chemoinformatics survey confirms the antagonistic interactions as a consequence of membrane potential/proton motive force dissipation. These data indicate cytochrome c oxidase as a target for 1.8-cineole toxicity action mechanisms.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1479
Author(s):  
Edelson de J. S. Dias ◽  
Antônio J. Cantanhede Filho ◽  
Fernando J. C. Carneiro ◽  
Cláudia Q. da Rocha ◽  
Luís Cláudio N. da Silva ◽  
...  

Humiria balsamifera (Aubl), commonly known as “mirim”, is a plant of the Humiriaceae family, which consists of 39 species divided between eight genera: Duckesia, Endopleura, Humiria, Humiriastrum, Hylocara, Sacoglottis, Schistostemon, and Vantenea. This study aimed to characterize H. balsamifera extracts by LC-MS/MS and evaluate their antimicrobial potential through in vitro and in vivo assays. The leaves and stem bark of H. balsamifera were collected and dried at room temperature and then ground in a knife mill. The extracts were prepared with organic solvents in order to increase the polarity index (hexane, ethyl acetate, and methanol). The antimicrobial effects of these extracts were evaluated against the following bacterial strains: Escherichia coli ATCC 25922, Listeria monocytogenes ATCC 15313, Salmonella enterica Typhimurium ATCC 14028, and Staphylococcus aureus ATCC 6538. The best activity was observed in the ethyl acetate (EALE = 780 µg/mL), methanol (MLE = 780 µg/mL), and hexane (HLE = 1560 µg/mL) leaf extracts against S. aureus. Considering the results for both antimicrobial and antibiofilm activities, the EALE extract was chosen to proceed to the infection assays, which used Tenebrio molitor larvae. The EALE treatment was able to extend the average lifespan of the larvae (6.5 days) in comparison to S. aureus-infected larvae (1 day). Next, the samples were characterized by High-Performance Liquid Chromatography coupled to a mass spectrometer, allowing the identification of 11 substances, including seven flavonoids, substances whose antimicrobial activity is already well-reported in the literature. The number of bioactive compounds found in the chemical composition of H. balsamifera emphasizes its significance in both traditional medicine and scientific research that studies new treatments based on substances from the Brazilian flora.


2021 ◽  
Vol 22 (1) ◽  
pp. 28-34
Author(s):  
Saddam Hussain Bughio

The objective of this study was to investigate the impact of phytochemical analysis and the antibacterial activity of extracts of stem, flowers and leaves of Tamarix dioica Roxb. ex Roth. Four solvents namely, diethyl ether, ethyl acetate, methanol and acetone were selected to obtain extracts from different parts of the plant. The organic solvent extracts were investigated for phytochemical analysis and antibacterial activity against two bacterial strains, namely Escherichia coli and Staphylococcus aureus. The result of phytochemicals revealed the presence of various constituents, such as phlobatannins, tannins, saponins, alkaloids, phenols, proteins, terpenoids, flavonoids and steroids by using standard procedures. Most of these components were present in methanol and ethyl acetate extract. Therefore, four out of two extracts, such as methanol and ethyl acetate extracts from stems, flowers, and leaves, were used to test their evidence of antibacterial activity. From this, it was observed that the methanol extracts of stem, flowers and leaves of T. dioica were highly effective together with E. coli and S. aureus with a minimum inhibitory concentration (MIC) value of 500 μg/mL. Considering that the ethyl acetate (EA) extracts from the stem, flowers and leaves of T. dioica were examined to be ineffective against E. coli and S. aureus and MIC values were not observed in two strains of bacteria.


2020 ◽  
Vol 16 (1) ◽  
pp. 72-79 ◽  
Author(s):  
Chaima Mouffouk ◽  
Leila Hambaba ◽  
Hamada Haba ◽  
Soumia Mouffouk ◽  
Chawki Bensouici

Objective: In this study, cytotoxic effect, anticholinesterase, hemolytic and antibacterial activities of crude extracts (petroleum ether, ethyl acetate and n-butanol) obtained from the plant Scabiosa stellata L. were evaluated. Methods: The cytotoxicity of extracts was tested by Brine shrimp lethality method; the acetylcholinesterase inhibitory activity was performed using Ellman's colorimetric method and the hemolytic activity was assessed by spectrophotometric method towards human erythrocytes. Furthermore, the antibacterial activity was estimated by agar disk diffusion assay against ten bacterial strains. Results: The phytochemical screening of the extracts revealed the presence of several types of secondary metabolites. A significant cytotoxic effect was observed for the n-butanolic extract with 57.2 ± 0.2 % of mortality at 80 μg/mL, the ethyl acetate extract had a moderate anticholinesterase activity at 200 μg/mL. The hemolytic assay exhibited that n-butanolic and ethyl acetate extracts induce hemolysis in dose-dependent manner with values of EC50 at 37.3 ± 0.5 and 106.6 ± 0.3 μg/mL, respectively. All the crude extracts showed antibacterial activity against most tested strains, with zones of inhibition ranging from 9 to 20 mm. Conclusion: The results indicate that the extracts obtained from S. stellata can be an important source of therapeutic agents against pathological damage due to free radicals inducing neurodegenerative and infectious diseases, while n-butanolic extract could be used as a good source of alternative natural antiproliferative compounds.


2008 ◽  
Vol 73 (12) ◽  
pp. 1153-1160 ◽  
Author(s):  
S.O. Podunavac-Kuzmanovic ◽  
V.M. Leovac ◽  
D.D. Cvetkovic

The antibacterial activities of cobalt(II) complexes with two series of benzimidazoles were evaluated in vitro against three Gram-positive bacterial strains (Bacillus cereus, Staphylococcus aureus, and Sarcina lutea) and one Gram-negative isolate (Pseudomonas aeruginosa). The minimum inhibitory concentration was determined for all the complexes. The majority of the investtigated complexes displayed in vitro inhibitory activity against very persistent bacteria. They were found to be more active against Gram-positive than Gram-negative bacteria. It may be concluded that the antibacterial activity of the compounds is related to the cell wall structure of the tested bacteria. Comparing the inhibitory activities of the tested complexes, it was found that the 1-substituted- -2-aminobenzimidazole derivatives were more active than complexes of 1-substituted- 2-amino-5,6-dimethylbenzimidazoles. The effect of chemical structure on the antibacterial activity is discussed.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6893 ◽  
Author(s):  
Raveevatoo Buathong ◽  
Voradol Chamchumroon ◽  
Johann Schinnerl ◽  
Markus Bacher ◽  
Wichai Santimaleeworagun ◽  
...  

Background A large number of secondary metabolites can be obtained from plants used for traditional medicine in two related genera (Ixora and Greenea) in the subfamily Ixoroideae (Rubiaceae), but there are only a few detailed studies on their bioactivities. Therefore, the main goals of this study were to determine the antibacterial activities of lipophilic extracts from plants of some Ixora and Greenea species native to Thailand, and to isolate some pure compounds from those extracts. Moreover, we compared the occurrence of compounds in different plant parts of samples from different habitats to better understand their variation. Methods A total of 56 lipophilic extracts were obtained from the leaves, stem bark, and root bark of eight Ixora and two Greenea species collected at various locations in Thailand. Isolated compounds were identified using nuclear magnetic resonance. Antimicrobial activities were evaluated against four Gram-positive and nine Gram-negative human pathogenic bacterial strains. Results Extracts from I. javanica, I. nigricans, I. brunonis, and G. montana, along with isolated scopoletin, exhibited antibacterial activities against Gram-positive methicillin-resistant Staphylococcus aureus ATCC 43300, with minimum inhibitory concentration values ranging from 64 to 256 µg/mL. The occurrence of scopoletin, isofraxidin, and geniposidic acid in lipophilic extracts showed some variation among different plant parts and species. Conclusions Lipophilic extracts of Ixora and Greenea species have the potential to be developed as anti-Gram-positive agents, in particular to counter infections of methicillin-resistant S. aureus strains. The chemical profiles showed differences between floristic regions but similarity within the same plant parts.


2019 ◽  
Vol 1 ◽  
pp. 33-37
Author(s):  
Y Gera ◽  
E U Umeh ◽  
T A Tor-Anyiin ◽  
C C Iheukwumere

The antibacterial activity of the stem bark of Detarium microcarpum was investigated with the aim of isolating the most active ingredient. Extraction solvents used to prepare the crude extracts of the stem bark were, n-hexane, ethyl acetate, chloroform, methanol. Test bacteria included Escherichia coli, Salmonella enteriditis, Shigella dysenteriae, Staphylococcus aureus and Vibro cholerae. The extracts demonstrated a wide range of antibacterial activity on the microorganisms, with the ethyl acetate crude extract being the most active. Using liquid vacuum chromatography over silica gel, the extract was eluted with n- hexane, ethyl acetate and methanol and fifty- five fractions labeled Gl - G55 were obtained. Further antibacterial assays of the fractions led to the identification of fraction G34 as the most active fraction. This fraction was subjected to spectroscopic analysis using NMR, [(1H -1H NMR, 13C-NMR) and 2D-NMR (COSY and HMBC)]. The results showed good agreement with reported data on Copalic acid, a diterpene with chemical formula C O H O . This compound is 2 34 2 the most active ingredients of this plant and is likely to be responsible for its antibacterial activities.


2014 ◽  
Vol 9 (11) ◽  
pp. 1934578X1400901 ◽  
Author(s):  
Dragoljub L. Miladinović ◽  
Budimir S. Ilić ◽  
Branislava D. Kocić ◽  
Marija D. Miladinović

The chemical composition and antibacterial activity of Satureja kitaibelii Wierzb. ex Heuff. (savory) essential oil were examined, as well as the association between it and standard antimicrobials: tetracycline and chloramphenicol. The antibacterial activities of geraniol, the main constituent of S. kitaibelii oil, individually and in combination with standard antimicrobials were also determined. The interactions of the essential oil and geraniol with antimicrobials toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods. Oxygenated monoterpenes were the most abundant compound class in the oil (59.7%), with geraniol (50.4%) as the major compound. The essential oil exhibited in vitro antibacterial activity against all tested bacterial strains, but the activities were lower than those of the standard antimicrobials. The combinations savory oil-chloramphenicol, savory oil-tetracycline and geraniol-chloramphenicol produced predominantly synergistic interactions (FIC indices in the range 0.21–0.87) and substantial reductions in the MIC values of antimicrobials against Gram-negative bacteria, the pharmacological treatment of which is very difficult nowadays. In the PCA and HCA analyses these combinations form a separate group.


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