scholarly journals Thiocarbamates from Moringa oleifera Seeds Bioactive against Virulent and Multidrug-Resistant Vibrio Species

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Renata Albuquerque Costa ◽  
Oscarina Viana de Sousa ◽  
Ernesto Hofer ◽  
Jair Mafezoli ◽  
Francisco Geraldo Barbosa ◽  
...  

Prospect of antibacterial agents may provide an alternative therapy for diseases caused by multidrug-resistant bacteria. This study aimed to evaluate the in vitro bioactivity of Moringa oleifera seed extracts against 100 vibrios isolated from the marine shrimp Litopenaeus vannamei. Ethanol extracts at low (MOS-E) and hot (MOS-ES) temperature are shown to be bioactive against 92% and 90% of the strains, respectively. The most efficient Minimum Inhibitory Concentration (MIC) levels of MOS-E and MOS-ES against a high percentage of strains were 32 µg mL−1. Bioguided screening of bioactive compounds showed that the ethyl acetate fraction from both extracts was the only one that showed antibacterial activity. Vibriocidal substances, niazirine and niazimicine, were isolated from the aforementioned fraction through chromatographic fractionation.

2021 ◽  
Vol 11 (2) ◽  
pp. 646-651
Author(s):  
Patricia Nascente ◽  
PEDRO RASSIER DOS SANTOS ◽  
HELENICE GONZALEZ DE LIMA ◽  
SILVIA DE OLIVEIRA HUBNER ◽  
PATRICIA DA SILVA NASCENTE

This work aims to verify the in vitro action of antiseptics used in the pre- and post-dipping against multidrug-resistant bacteria from bovine mastitis. Antiseptic solutions in the concentration of use of iodine, chlorhexidine and sodium hypochlorite were tested against Staphylococcus aureus (n=12), Staphylococcus sciuri (n=1), Staphylococcus lentus (n=1), Streptococcus sp. (n=1), Enterococcus faecalis (n=1), Enterococcus casseliflavus (n=1), Kocuria kristinae (n=2), Kocuria varians (n=1). Was verified the Minimal Inhibitory and Bactericidal Concentration. The cytotoxicity test complemented the work. It was found that the Minimal Inhibitory Concentration and Minimal Bactericidal Concentration of the iodine, sodium hypochlorite and chlorhexidine was effective in the values recommended for use, however the presence of organic material reduced the activity of the tested products. Chlorhexidine showed higher efficiency of the other disinfectants.


Author(s):  
Sami Khabthani ◽  
Mouna Hamel ◽  
Sophie Alexandra Baron ◽  
Seydina Diene ◽  
Jean-Marc Rolain ◽  
...  

Fosfomycin is a decades-old antibiotic, currently reused because of its activity against multidrug resistant bacteria. Here, we used a combined in vitro/in silico approach to search for fosfomycin resistance determinants in 25 new bacterial species isolated from the human microbiota. Putative resistance genes were cloned into a susceptible Escherichia coli. Minimal Inhibitory Concentration (MIC) values increased from 1 μg/ml to 1024 μg/ml. We report here new family of potential chromosomal fosfomycin resistance genes named fosM.


2021 ◽  
Vol 22 (10) ◽  
Author(s):  
Muhammad Evy Prastiyanto

Abstract. Prastiyanto ME. 2021. Seeds extract of three Artocarpus species: Their in-vitro antibacterial activities against multidrug-resistant (MDR) Escherichia coli isolates from urinary tract infections (UTIs). Biodiversitas 22: 4362-4368. Multidrug-resistant (MDR)-E. coli is a major cause and has become a very serious problem in urinary tract infections (UTIs). As a result, it requires an antibacterial agent derived from biological materials. It has been reported that the seeds of three species of Artocarpus (A. heterophyllous, A. champeden, and A. camansi) have antibacterial properties against Methicillin-Resistant Staphylococcus aureus (MRSA). However, there are three other Artocarpus species in Indonesia, i.e., keledang (A. lanceipolius), tarra (A. elasticus), and terap (A. Odoratissimus) whose antibacterial property has not been investigated. To minimize the research gap, this study aims to determine the antibacterial activity of seed extracts of A. lanceipolius, A. elasticus, and A. odoratissimus against MDR-E. coli isolates of UTIs. Antibacterial activity was evaluated using the agar well diffusion assay. The microdilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. The results revealed that the seed extracts of A. lanceipolius, A. elasticus, and A. odoratissimus have the potential as antibacterial agents against MDR-E. coli isolate of UTIs. A. elasticus seed extract shows the widest zone of inhibition in the range of 7.0-13.3 mm and the smallest MIC and MBC values ??of 6.25-12.5 mg/mL and 12.5-25 mg/mL, respectively. In conclusion, A. lanceipolius, A. elasticus, and A. odoratissimus seed extracts have the potential to be developed as antibacterial agents against UTI-causing MDR-E. coli. Further in vivo research and determining the mode of action of antibacterial activity are needed.


2015 ◽  
Vol 15 (1) ◽  
pp. 1 ◽  
Author(s):  
Krishna Patel ◽  
Arwa Kaizer Ali ◽  
Nishith Nair ◽  
Vijay Kothari

Extracts of the Pongamia pinnata, Manilkara hexandra, and Pyrus pyrifolia seeds prepared by microwave assisted extraction method, and the violet pigment- violacein extracted from Chromobacterium violaceoum were screened for their antibacterial activity against Streptococcus mutans.M. hexandra extracts were able to inhibit both the test strains of S. mutans used in this study with minimum inhibitory concentration (MIC) ranging from 600-800 µg/mL. These extracts exerted bactericidal action against S. mutans with minimum bactericidal concentration (MBC) of 600-900 µg/mL. Acetone extract of M. hexandra seeds registered highest average total activity of 231.20 mL/g. Extraction efficiency was found to have a moderately good correlation with antibacterial activity. Violacein exerted bactericidal action with MIC and MBC of less than 2 µg/mL against both the strains.


2020 ◽  
Vol 15 (3) ◽  
pp. 193-206
Author(s):  
Brognara Lorenzo ◽  
Salmaso Luca ◽  
Mazzotti Antonio ◽  
Di M. Alberto ◽  
Faldini Cesare ◽  
...  

Background: Chronic wounds are commonly associated with polymicrobial biofilm infections. In the last years, the extensive use of antibiotics has generated several antibiotic-resistant variants. To overcome this issue, alternative natural treatments have been proposed, including the use of microorganisms like probiotics. The aim of this manuscript was to review current literature concerning the application of probiotics for the treatment of infected chronic wounds. Methods: Relevant articles were searched in the Medline database using PubMed and Scholar, using the keywords “probiotics” and “wound” and “injuries”, “probiotics” and “wound” and “ulcer”, “biofilm” and “probiotics” and “wound”, “biofilm” and “ulcer” and “probiotics”, “biofilm” and “ulcer” and “probiotics”, “probiotics” and “wound”. Results: The research initially included 253 articles. After removal of duplicate studies, and selection according to specific inclusion and exclusion criteria, 19 research articles were included and reviewed, accounting for 12 in vitro, 8 in vivo studies and 2 human studies (three articles dealing with animal experiments included also in vitro testing). Most of the published studies about the effects of probiotics for the treatment of infected chronic wounds reported a partial inhibition of microbial growth, biofilm formation and quorum sensing. Discussion: The application of probiotics represents an intriguing option in the treatment of infected chronic wounds with multidrug-resistant bacteria; however, current results are difficult to compare due to the heterogeneity in methodology, laboratory techniques, and applied clinical protocols. Lactobacillus plantarum currently represents the most studied strain, showing a positive application in burns compared to guideline treatments, and an additional mean in chronic wound infections. Conclusions: Although preliminary evidence supports the use of specific strains of probiotics in certain clinical settings such as infected chronic wounds, large, long-term clinical trials are still lacking, and further research is needed.


2020 ◽  
Vol 9 (1) ◽  
pp. 416-428 ◽  
Author(s):  
Raghad R. Alzahrani ◽  
Manal M. Alkhulaifi ◽  
Nouf M. Al-Enazi

AbstractThe adaptive nature of algae results in producing unique chemical components that are gaining attention due to their efficiency in many fields and abundance. In this study, we screened the phytochemicals from the brown alga Hydroclathrus clathratus and tested its ability to produce silver nanoparticles (AgNPs) extracellularly for the first time. Lastly, we investigated its biological activity against a variety of bacteria. The biosynthesized nanoparticles were characterized by UV-visible spectroscopy, Fourier-transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and energy-dispersive spectroscopy. The biological efficacy of AgNPs was tested against eighteen different bacteria, including seven multidrug-resistant bacteria. Phytochemical screening of the alga revealed the presence of saturated and unsaturated fatty acids, sugars, carboxylic acid derivatives, triterpenoids, steroids, and other components. Formed AgNPs were stable and ranged in size between 7 and 83 nm and presented a variety of shapes. Acinetobacter baumannii, Staphylococcus aureus, Methicillin-resistant S. aureus (MRSA), and MDR A. baumannii were the most affected among the bacteria. The biofilm formation and development assay presented a noteworthy activity against MRSA, with an inhibition percentage of 99%. Acknowledging the future of nano-antibiotics encourages scientists to explore and enhance their potency, notably if they were obtained using green, rapid, and efficient methods.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 751
Author(s):  
Marwa Reda Bakkar ◽  
Ahmed Hassan Ibrahim Faraag ◽  
Elham R. S. Soliman ◽  
Manar S. Fouda ◽  
Amir Mahfouz Mokhtar Sarguos ◽  
...  

COVID-19 is a pandemic disease caused by the SARS-CoV-2, which continues to cause global health and economic problems since emerging in China in late 2019. Until now, there are no standard antiviral treatments. Thus, several strategies were adopted to minimize virus transmission, such as social distancing, face covering protection and hand hygiene. Rhamnolipids are glycolipids produced formally by Pseudomonas aeruginosa and as biosurfactants, they were shown to have broad antimicrobial activity. In this study, we investigated the antimicrobial activity of rhamnolipids against selected multidrug resistant bacteria and SARS-CoV-2. Rhamnolipids were produced by growing Pseudomonas aeruginosa strain LeS3 in a new medium formulated from chicken carcass soup. The isolated rhamnolipids were characterized for their molecular composition, formulated into nano-micelles, and the antibacterial activity of the nano-micelles was demonstrated in vitro against both Gram-negative and Gram-positive drug resistant bacteria. In silico studies docking rhamnolipids to structural and non-structural proteins of SARS-CoV-2 was also performed. We demonstrated the efficient and specific interaction of rhamnolipids with the active sites of these proteins. Additionally, the computational studies suggested that rhamnolipids have membrane permeability activity. Thus, the obtained results indicate that SARS-CoV-2 could be another target of rhamnolipids and could find utility in the fight against COVID-19, a future perspective to be considered.


2021 ◽  
Vol 22 (13) ◽  
pp. 7202
Author(s):  
Tamara Bruna ◽  
Francisca Maldonado-Bravo ◽  
Paul Jara ◽  
Nelson Caro

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 877
Author(s):  
Ana Mafalda Pinto ◽  
Alberta Faustino ◽  
Lorenzo M. Pastrana ◽  
Manuel Bañobre-López ◽  
Sanna Sillankorva

Pseudomonas aeruginosa is responsible for nosocomial and chronic infections in healthcare settings. The major challenge in treating P. aeruginosa-related diseases is its remarkable capacity for antibiotic resistance development. Bacteriophage (phage) therapy is regarded as a possible alternative that has, for years, attracted attention for fighting multidrug-resistant infections. In this work, we characterized five phages showing different lytic spectrums towards clinical isolates. Two of these phages were isolated from the Russian Microgen Sextaphage formulation and belong to the Phikmvviruses, while three Pbunaviruses were isolated from sewage. Different phage formulations for the treatment of P. aeruginosa PAO1 resulted in diversified time–kill outcomes. The best result was obtained with a formulation with all phages, prompting a lower frequency of resistant variants and considerable alterations in cell motility, resulting in a loss of 73.7% in swimming motility and a 79% change in swarming motility. These alterations diminished the virulence of the phage-resisting phenotypes but promoted their growth since most became insensitive to a single or even all phages. However, not all combinations drove to enhanced cell killings due to the competition and loss of receptors. This study highlights that more caution is needed when developing cocktail formulations to maximize phage therapy efficacy. Selecting phages for formulations should consider the emergence of phage-resistant bacteria and whether the formulations are intended for short-term or extended antibacterial application.


Sign in / Sign up

Export Citation Format

Share Document