Colombian frogs: promising source of new antibiotics

2020 ◽  
Author(s):  
Esteban Alzate ◽  
Laura Mejía ◽  
Maria Clara Nuñez ◽  
Julie Benavides ◽  
David Galvis-Pareja ◽  
...  

Abstract Background: In middle Magdalena of the Antioquia region, Colombia frog secretions have been used as antibacterial agents, the purpose of this study is to assess the antibacterial activity of six frog species secretions. Methods: the Kirby-Bauer and the microdilution methods were used to evaluate antibacterial activity of the frogs secretions against S. aureus and E. coli, using two positive controls, ampicillin and ciprofloxacin. Results: secretions of all six families showed inhibition zones, the concentration at which this zone was bigger was assayed later by the microdilution method and compared to ampicillin and ciprofloxacin. Only the secretion from the Phyllomedusidae exhibited a comparable effect to that one of control antibiotics. Conclusions: in here we provide evidence that secretions from local frogs have an antibacterial effect against two strains of bacteria, further studies are needed to identify the peptides in the secretions and a wider range of safe concentrations for human use.

Author(s):  
Olufunmiso O. Olajuyigbe ◽  
Morenike O. Adeoye-Isijola ◽  
Otunola Adedayo

Background: Black soap is a medicinal product that could be harnessed for economic purpose if properly packaged, and misconception about its traditional use by herbalists is thrown overboard.Aims: To promote the relevance of these soaps for economic development, this study compared the antibacterial activity of black soaps with medicated soaps widely used against bacterial infections.Methods: The antibacterial activities of these soap samples were determined by agar diffusion and macrobroth dilution methods.Results: In this study, the statistical analysis of the inhibition zones showed that black soaps were significantly (p < 0.05) more active than medicated soaps used against the test bacterial isolates. The black soaps inhibited and killed the isolates better than the medicated soaps at the different concentrations used. The minimum inhibitory concentration for Klebsiella pneumoniae and Enterococcus faecalis ranged between 0.125 mg/mL and 2 mg/mL, Staphylococcus aureus (0.25–4) mg/mL, Escherichia coli (0.125–4) mg/mL and Pseudomonas aeruginosa (1–4) mg/mL. The result showed that K. pneumoniae and E. faecalis were the most susceptible, followed by E. faecalis > E. coli > S. aureus > P. aeruginosa.Conclusion: As a valuable medicinal output derivable from organic waste product that could be converted to wealth, African black soap production, utilisation and commercialisation have tremendous economic potentials. These soaps showed significant antibacterial activity greater than those of the medicated soaps. Hence, their use could be a better option in place of commercially available medicated and antiseptic soaps because of the degree of antibacterial activities they exhibited.


2020 ◽  
Vol 4 (2) ◽  

Metal nanoparticles possess an extensive scientific and technological significance due to their unique physiochemical properties and their potential applications in different fields like medicine. Silver and gold nanoparticles have shown to have antibacterial and cytotoxic activities. Conventional methods used in the synthesis of the metal nanoparticles involve use of toxic chemicals making them unsuitable for use in medical field. In our continued effort to explore for simple and eco-friendly methods to synthesize the metal nanoparticles, we here describe synthesis and characterization of gold and silver nanoparticles using Gonaderma lucidum, wild non-edible medicinal mushroom. G. lucidum mushroom contain bioactive compounds which can be involved in the reduction, capping and stabilization of the nanoparticles. Antibacterial activity analysis was done on E. coli and S. aureus. The synthesis was done on ultrasonic bath. Characterization of the metal nanoparticles was done by UV-VIS., High Resolution Transmission Electron Microscope (HRTEM) and FTIR. HRTEM analysis showed that both silver and gold nanoparticles were spherical in shape with an average size of 15.82±3.69 nm for silver and 24.73±5.124nm for gold nanoparticles (AuNPs). FTIR analysis showed OH and -C=C- stretching vibrations, an indication of presence of functional groups of biomolecules capping both gold and silver nanoparticles. AgNPs showed inhibition zones of 15.5±0.09mm and 13.3±0.14mm while AuNPs had inhibition zones of 14.510±0.35 and 13.3±0.50mm on E. coli and S. aureus respectively. The findings indicate the potential use of AgNPs and AuNPs in development of drugs in management of pathogenic bacteria.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Khalid Chebbac ◽  
Abdelfattah EL Moussaoui ◽  
Mohammed Bourhia ◽  
Ahmad Mohammad Salamatullah ◽  
Abdulhakeem Alzahrani ◽  
...  

Background. Artemisia negrei L. (A. negrei) is a medicinal and aromatic plant belonging to the family Asteraceae that is more widespread in the folded Middle Atlas Mountains, Morocco. Materials and Methods. This study was run to investigate the phytochemical composition and antioxidant, antibacterial, and antifungal activities of Artemisia negrei L. essential oil. This oil was extracted from the fresh plant material by using the Clevenger apparatus. The phytochemical composition was characterized by GC-MS. The antioxidant activity was evaluated using different methods including DPPH, β-carotene bleaching, and total antioxidant capacity. The antibacterial activity was tested vs. multidrug-resistant bacteria including both Gram-negative and Gram-positive using inhibition zones in agar media and minimum inhibitory concentration (MIC) bioassays. The antifungal activity was conducted on Candida albicans, Aspergillus niger, Aspergillus flavus, and Fusarium oxysporum using a solid medium assay. Results. The chromatographic characterization of essential oils of A. negrei revealed the presence of 34 compounds constituting 99.91% of the total essential oil. The latter was found to have promising antioxidant activity by all bioassays used such as DPPH, β-carotene bleaching, and total antioxidant capacity. The results obtained showed that our plant oils had potent antibacterial activity towards Gram-negative (E. coli 57, E. coli 97, K. pneumonia, and P. aeruginosa) and Gram-positive (S. aureus), so that the maximum inhibition zones and MIC values were around 18–37 mm and 3.25 to 12.5 mg/mL, respectively. The oil also showed antifungal activity towards Candida albicans, Fusarium oxysporum, and Aspergillus Niger except for flavus species. Conclusion. The findings obtained in the work showed that A. negrei can serve as a valuable source of natural compounds that can be used as a new weapon to fight radical damage and resistant microbes.


2020 ◽  
Vol 11 (3) ◽  
pp. 10082-10088

Marine sponge Callyspongia sp. is one full of potency as a source for discovering and developing novel antibacterial. This study aims to isolate the Callypsongia sp. and assay their antibacterial activity. Callyspongia sp. were macerated with ethyl acetate (3x24 hrs), isolated with vacuum liquid chromatography (VLC) and RC (radial chromatography), and determined their structure with 1H and 13C-NMR. The antibacterial activity was assayed with the microdilution method. From ethyl acetate extract of Callyspongia sp. was successfully 2 isolated compounds, namely, isolate C1 (cholesterol) and isolate C2 (Unknown alkaloid with carbonyl from aldehyde group). The extract has MIC>512 µg/mL against Bacillus subtilis, Escherichia coli, Streptococcus mutans, and Salmonella enterica. While in both isolates provided MIC value >256 µg/mL against B. subtilis, E. coli, and S. mutans, yet in S. enterica provided 128 µg/mL for isolate C1 and 256 µg/mL for isolate C2. In conclusion, ethyl acetate extract of Callyspongia sp. contains cholesterol and Unknown alkaloid with carbonyl from the aldehyde group, and they both exhibited low antibacterial susceptibility.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Paola Cynthia Emoh Demeni ◽  
Patrick Hervé Diboue Betote ◽  
Christelle Wayoue Kom ◽  
Eric Ngalani Tchamgoue ◽  
Esther Del Florence Ndedi Moni ◽  
...  

This study evaluated the antibacterial efficacy of methanolic extracts of isolated endophytic fungi from stem barks and leaves of Alstonia boonei De Wild and Greenwayodendron suaveolens (Engl. and Diels) Verdc. subsp. Suaveolens against Klebsiella pneumoniae ATCC 43816, Haemophilus influenzae ATCC 49247, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 35218, responsible for causing pneumonia. The endophytic fungi were isolated and characterized in the Potato Dextrose Agar (PDA), Sabouraud Dextrose Agar (SDA), and Czapek Dox Agar (CDA) media. The fungi and their methanolic extracts were tested for in vitro antibacterial potential by antagonistic assay for endophytic fungi against bacterial pathogens and microdilution method. The phytochemical screening of extracts was carried out according to the colorimetric and precipitation methods to reveal the presence of secondary metabolites. The results showed that 24 macroscopically and microscopically distinct endophytic fungi were isolated, identified, and stored. These endophytic fungi possessed antibacterial activity against the selected bacterial strains with inhibition zones ranging from 7.00 to 25.00 mm. The endophytic fungi GS15 and AB24 have presented the inhibitions zones of 20.33 mm and 25.00 mm, respectively, and these were better than the ones obtained for Levofloxacin®. The endophytes with inhibition zones greater than 10 mm were used for extraction of their secondary metabolites. The endophytic fungi extracts showed antibacterial activity with the minimum inhibitory concentrations (MICs) ranging from 6.25 × 10−4 to 2 × 10−2 g/L and the minimum bactericidal concentrations (MBCs) ranging from 2.5 × 10−3 to 2 × 10−2 g/L. The endophytic fungi GS15 extract was the most effective extract; it showed bactericidal effects on the tested bacterial strains. The phytochemical screening of the extracts revealed the presence of secondary metabolites classes, responsible for causing the obtained antibacterial activity. Thus, the endophytic fungi methanolic extracts from A. boonei and G. suaveolens have the potential to inhibit the growth of bacteria responsible for nosocomial pneumonia.


2021 ◽  
Author(s):  
Bondy Lourenço ◽  
Asimbawe Kiza ◽  
Abrão Amândio João ◽  
Clemência Félix Odala Niconte ◽  
Pompílio Armando Vintuar ◽  
...  

Abstract Background: Currently, several studies are being conducted to test antibacterial activity of various medicinal plants, in attempt to develop new antibiotics or to potentiate the action of antibiotics of known clinical use. In this research, phytochemical analysis and in vitro antibacterial activity of leaf extracts of Lantana camara L were performed.Methods The extracts were obtained through maceration with 90% ethanol. In phytochemical analysis, alkaloids, flavonoids, tannins and saponins were identified using specific reagents for each class.The antibacterial activity was analyzed using the disk diffusion method according to Kirby-Bauer, against Escherichia coli and Staphylococus aureus.Key findings The diameters of the inhibition halos varied between 0.7 and 12 mm, with an average of 8.26 mm for strains of S. aureus and there was no inhibition for E. coli. The results showed a significant difference between the inhibition halos and the tested concentrations for S. aureus. In conclusion L. camara leaf extracts are rich in bioactive compounds and have a good antibacterial potential against S. aureus and not for E. coli. And there was no relationship between the concentration of the extract and the diameter of the halo of inhibition of the evaluated microorganism.


2020 ◽  
Vol 21 (6) ◽  
Author(s):  
Maria Masitho Makajanma ◽  
Intan Taufik ◽  
Ahmad Faizal

Abstract. Makajanma MM, Taufik I, Faizal A. 2020. Antioxidant and antibacterial activity of extract from two species of mosses: Leucobryum aduncum and Campylopus schmidii. Biodiversitas 21: 1751-1758.  Plants produce a plethora of natural compounds of medicinal value. Although most plant-derived drugs have been identified in angiosperms, some species of mosses from the genera Leucobryum and Campylopus also exhibit antioxidant and antibacterial activity. The research aimed to evaluate the antioxidant and antibacterial activities of two species of these genera, Leucobryum aduncum and Campylopus schmidii, that are common in Taman Wisata Alam Gunung Tangkuban Perahu, West Java. Plants were collected, dried, and extracted in n-hexane or methanol. Antioxidant activity was evaluated by determining the concentration of extract that resulted in 50% reduction of 1,1-diphenyl-2-picrylhydrazine (DPPH) in the DPPH assay. These concentrations were >2000 mg/L for L. aduncum extracts and 1329.02 ± 7.8 mg/L for C. schmidii extracts; these large values are consistent with little antioxidant activity. Antibacterial activity was quantified as the ability of the extracts to inhibit the growth of the Gram-negative and Gram-positive bacteria Escherichia coli and Staphylococcus aureus, respectively. Nonpolar extracts of L. aduncum inhibited the growth of E. coli >50% at a concentration of 32 mg extract/L. Based on combined gas chromatography-mass spectrometry, the antibacterial activity in the non-polar extracts of L. aduncum was attributed to the lipophilic compounds 1-nonadecene, 5-eicosene, and cyclotetracosane. Thus, L. aduncum is a promising candidate as a source of new antibiotics.


2021 ◽  
Author(s):  
Bondy Jorge Lourenço ◽  
Asimbawe Kiza ◽  
ABRÃO AMÂNDIO JOÃO ◽  
Clemência FÉLIX ODALA Niconte ◽  
POMPÍLIO ARMANDO Vintuar ◽  
...  

Abstract Background: Currently, several studies are being conducted to test antibacterial activity of various medicinal plants, in attempt to develop new antibiotics or to potentiate the action of antibiotics of known clinical use. In this research, phytochemical analysis and in vitro antibacterial activity of leaf extracts of Lantana camara L were performed.The extracts were obtained through maceration with 90% ethanol. In phytochemical analysis, alkaloids, flavonoids, tannins and saponins were identified using specific reagents for each class.The antibacterial activity was analyzed using the disk diffusion method according to Kirby-Bauer, against Escherichia coli and Staphylococus aureus. Results: The diameters of the inhibition halos varied between 0.7 and 12 mm, with an average of 8.26 mm for strains of S. aureus and there was no inhibition for E. coli. The results showed a significant difference between the inhibition halos and the tested concentrations for S. aureus. Conclusions: L. camara leaf extracts are rich in bioactive compounds and have a good antibacterial potential against S. aureus and not for E. coli. And there was no relationship between the concentration of the extract and the diameter of the halo of inhibition of the evaluated microorganism.


2018 ◽  
Vol 24 (3) ◽  
pp. 240-245
Author(s):  
Lamia Boudjedjou ◽  
Messaoud Ramdani ◽  
Azzeddine Zeraib ◽  
Tarek Benmeddour ◽  
Azzedine Fercha

Background: Over the past decade, most antibiotic research programs have focused on finding new compounds with antimicrobial activity. This study aims to investigate the chemical composition and antibacterial activity of the essential oil (EO) extracted from ripe berries of Algerian Juniperus thurifera var. aurasiaca. Methods: The chemical composition of J. thurifera EO extracted by hydrodistillation was analyzed by using the GC-MS technique. Antibacterial activity of EO alone and in combination with three conventional antibiotics was assessed by using disc diffusion method against four bacterial strains. Results: Thirty-five components were identified, representing ~87 % of the oil. The main components were m-mentha-6,8-diene (15.43 %), β-pinene (10.59 %), elemol (8.31 %) and terpinene-4-ol (7.44 %). The essential oil showed strong antibacterial activity against S. aureus and E. coli, but no activity against P. aeruginosa and B. subtilis. Synergistic effects were observed because of the combined application of EO with gentamicin against all strains tested, and with amoxicillin against B. subtilis. Furthermore, the combination of EO/cefazolin demonstrated an additive effect against B. subtilis. In contrast, the combination of EO with amoxicillin and céfazoline revealed antagonistic effects against S. aureus, E. coli, and P. aeruginosa. Conclusion: This is the first report on the chemical composition and antibacterial activity of Algerian juniper berries’ essential oil. The results indicate that the studied EO may be a promising source of antibacterial compounds that could be useful for pharmaceutical applications especially in combination with conventional antibiotics.


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