scholarly journals The antimicrobial capacity of Cistus salviifolius and Punica granatum plant extracts against clinical pathogens is related to their polyphenolic composition

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francisco Javier Álvarez-Martínez ◽  
Juan Carlos Rodríguez ◽  
Fernando Borrás-Rocher ◽  
Enrique Barrajón-Catalán ◽  
Vicente Micol
Keyword(s):  
Antibiotic Resistance ◽  
Bacterial Resistance ◽  
Punica Granatum ◽  
Resistance Profile ◽  
Quercetin Derivatives ◽  
Hydrolyzable Tannins ◽  
Polyphenolic Composition ◽  
Cell Wall Disruption ◽  
Cistus Salviifolius ◽  
Botanical Extracts

AbstractAntimicrobial resistance poses a serious threat to human health worldwide. Plant compounds may help to overcome antibiotic resistance due to their potential resistance modifying capacity. Several botanical extracts and pure polyphenolic compounds were screened against a panel of eleven bacterial isolates with clinical relevance. The two best performing agents, Cistus salviifolius (CS) and Punica granatum (GP) extracts, were tested against 100 Staphylococcus aureus clinical isolates, which resulted in average MIC50 values ranging between 50–80 µg/mL. CS extract, containing hydrolyzable tannins and flavonoids such as myricetin and quercetin derivatives, demonstrated higher activity against methicillin-resistant S. aureus isolates. GP extract, which contained mostly hydrolyzable tannins, such as punicalin and punicalagin, was more effective against methicillin-sensitive S. aureus isolates. Generalized linear model regression and multiple correspondence statistical analysis revealed a correlation between a higher susceptibility to CS extract with bacterial resistance to beta-lactam antibiotics and quinolones. On the contrary, susceptibility to GP extract was related with bacteria sensitive to quinolones and oxacillin. Bacterial susceptibility to GP and CS extracts was linked to a resistance profile based on cell wall disruption mechanism. In conclusion, a differential antibacterial activity against S. aureus isolates was observed depending on antibiotic resistance profile of isolates and extract polyphenolic composition, which may lead to development of combinatorial therapies including antibiotics and botanical extracts.

scholarly journals Bacterial Resistance in Ophthalmology – Resistance Profile, Influencing Factors and Prevention Methods. A Review

2021 ◽  
Vol 28 (2) ◽  
pp. 127-137
Author(s):  
Matei POPA-CHERECHEANU ◽  
◽  
Alina POPA-CHERECHEANU ◽  
Dan George DELEANU ◽  
Mihai Aurelian GHITA ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Multidrug Resistance ◽  
Antimicrobial Resistance ◽  
Influencing Factors ◽  
Bacterial Resistance ◽  
Topical Antibiotics ◽  
Resistance Profile ◽  
Ocular Infections ◽  
Prevention Methods ◽  
New Treatments

Ocular infections vary greatly in severity. Studies have tried to identify certain patterns related to the ocular microbiome in the studied populations in order to identify risk populations, new treatments and prophylaxis guidelines. However, it is critical to determine which antibiotics should be used in various situations and where alternatives to antibiotics are appropriate. Results of many studies show that high levels of antibiotic resistance in ophthalmology and multidrug resistance continue to be a reality and a challenge today. Iodine-povidone and chlorhexidine are two major antiseptics used in ophthalmology. It is hoped that future reports show good results without the use of antibiotics will encourage ophthalmologists to limit the use of topical antibiotics, reducing the rate of antimicrobial resistance.

scholarly journals Comparison of Antibiotic Resistance Profile of Escherichia coli between Pristine and Human-Impacted Sites in a River

Antibiotics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 575
Author(s):  
Emi Nishimura ◽  
Masateru Nishiyama ◽  
Kei Nukazawa ◽  
Yoshihiro Suzuki
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Resistant Bacteria ◽  
Downstream Site ◽  
Antibiotic Resistant Bacteria ◽  
Antibiotic Resistant ◽  
Upstream Site ◽  
Resistance Profile ◽  
Antibiotic Resistance Profile ◽  
Significant Difference

Information on the actual existence of antibiotic-resistant bacteria in rivers where sewage, urban wastewater, and livestock wastewater do not load is essential to prevent the spread of antibiotic-resistant bacteria in water environments. This study compared the antibiotic resistance profile of Escherichia coli upstream and downstream of human habitation. The survey was conducted in the summer, winter, and spring seasons. Resistance to one or more antibiotics at upstream and downstream sites was on average 18% and 20%, respectively, and no significant difference was observed between the survey sites. The resistance rates at the upstream site (total of 98 isolated strains) to each antibiotic were cefazolin 17%, tetracycline 12%, and ampicillin 8%, in descending order. Conversely, for the downstream site (total of 89 isolated strains), the rates were ampicillin 16%, cefazolin 16%, and tetracycline 1% in descending order. The resistance rate of tetracycline in the downstream site was significantly lower than that of the upstream site. Furthermore, phylogenetic analysis revealed that many strains showed different resistance profiles even in the same cluster of the Pulsed-Field Gel Electrophoresis (PFGE) pattern. Moreover, the resistance profiles differed in the same cluster of the upstream and the downstream sites. In flowing from the upstream to the downstream site, it is plausible that E. coli transmitted or lacked the antibiotic resistance gene.

scholarly journals Variation of the Polyphenolic Composition and Antioxidant Capacity of Freshly Prepared Pomegranate Leaf Infusions over One-Day Storage

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1187
Author(s):  
Manyou Yu ◽  
Irene Gouvinhas ◽  
Ana Barros
Keyword(s):  
Antioxidant Capacity ◽  
Gallic Acid ◽  
Antioxidant Properties ◽  
Punica Granatum ◽  
Added Value ◽  
Plant Materials ◽  
Polyphenolic Composition ◽  
Punica Granatum L ◽  
Intensive Search ◽  
By Products

In recent decades, an intensive search for natural and novel types of antioxidant polyphenolics has been carried out on numerous plant materials. However, the current literature has very little information on their storage stability in the form of freshly prepared infusions. This study aims to characterize the polyphenolic composition and the antioxidant capacity of pomegranate (Punica granatum L.) leaf infusions over one-day storage (analyzed at 0, 2, 4, 6, 8, and 24 h). Spectrophotometric evaluation demonstrated that the infusion presented no significant changes in the content of total phenols (131.40–133.47 mg gallic acid g−1) and ortho-diphenols (239.91–244.25 mg gallic acid g−1). The infusion also maintained high stability (over 98% and 82%, respectively) for flavonoids (53.30–55.84 mg rutin g−1) and condensed tannins (102.15–124.20 mg epicatechin g−1), with stable (>90%) potent antioxidant capacity (1.5–2.2 mmol Trolox g−1) throughout 0–24 h storage. The main decrease was observed during 0–2 h storage of flavonoids, 8–24 h storage of tannins, and 0–4 h storage of antioxidant capacity. Chromatographic analysis further revealed that 7 decreased and 11 increased compounds were found within 0–24 h storage. The good stability of the total polyphenolics and antioxidant properties might be related to the complex conversion and activity compensation among these compounds. The findings suggest that pomegranate leaf infusion could be of great interest in the valorization of high added-value by-products and in the application of green and functional alternatives in the food-pharma and nutraceutical industries.

scholarly journals In VivoImpact of Met221 Substitution in GOB Metallo-β-Lactamase

2012 ◽  
Vol 56 (4) ◽  
pp. 1769-1773 ◽  
Author(s):  
Jorgelina Morán-Barrio ◽  
María-Natalia Lisa ◽  
Alejandro J. Vila
Keyword(s):  
Antibiotic Resistance ◽  
Protein Stability ◽  
Metal Binding ◽  
Active Sites ◽  
Bacterial Resistance ◽  
Structural Diversity ◽  
Hydrophobic Core

ABSTRACTMetallo-β-lactamases (MβLs) represent one of the main mechanisms of bacterial resistance against β-lactam antibiotics. The elucidation of their mechanism has been limited mostly by the structural diversity among their active sites. All MβLs structurally characterized so far present a Cys or a Ser residue at position 221, which is critical for catalysis. GOB lactamases stand as an exception within this picture, possessing a Met residue in this location. We studied different mutants in this position, and we show that Met221 is essential for protein stability, most likely due to its involvement in a hydrophobic core. In contrast to other known MβLs, residue 221 is not involved in metal binding or in catalysis in GOB enzymes, further highlighting the structural diversity of MβLs. We also demonstrate the usefulness of protein periplasmic profiles to assess the contribution of protein stability to antibiotic resistance.

scholarly journals COVID-19 Lockdowns May Reduce Resistance Genes Diversity in the Human Microbiome and the Need for Antibiotics

2021 ◽  
Vol 22 (13) ◽  
pp. 6891
Author(s):  
João S. Rebelo ◽  
Célia P. F. Domingues ◽  
Francisco Dionisio ◽  
Manuel C. Gomes ◽  
Ana Botelho ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Bacterial Resistance ◽  
Human Microbiome ◽  
Antibiotic Resistance Genes ◽  
Public Health Problem ◽  
Small World ◽  
Physical Contact ◽  
Hygiene Measures

Recently, much attention has been paid to the COVID-19 pandemic. Yet bacterial resistance to antibiotics remains a serious and unresolved public health problem that kills hundreds of thousands of people annually, being an insidious and silent pandemic. To contain the spreading of the SARS-CoV-2 virus, populations confined and tightened hygiene measures. We performed this study with computer simulations and by using mobility data of mobile phones from Google in the region of Lisbon, Portugal, comprising 3.7 million people during two different lockdown periods, scenarios of 40 and 60% mobility reduction. In the simulations, we assumed that the network of physical contact between people is that of a small world and computed the antibiotic resistance in human microbiomes after 180 days in the simulation. Our simulations show that reducing human contacts drives a reduction in the diversity of antibiotic resistance genes in human microbiomes. Kruskal–Wallis and Dunn’s pairwise tests show very strong evidence (p < 0.000, adjusted using the Bonferroni correction) of a difference between the four confinement regimes. The proportion of variability in the ranked dependent variable accounted for by the confinement variable was η2 = 0.148, indicating a large effect of confinement on the diversity of antibiotic resistance. We have shown that confinement and hygienic measures, in addition to reducing the spread of pathogenic bacteria in a human network, also reduce resistance and the need to use antibiotics.

scholarly journals ANTIBIOTIC RESISTANCE PROFILING OF DAIRY WASTEWATER DEGRADING NATIVE EFFICIENT MICROBIAL ISOLATES

2017 ◽  
Vol 10 (7) ◽  
pp. 145
Author(s):  
Anupama Bhardwaj ◽  
Jagtar Singh ◽  
Sonia Chaman ◽  
Amit Joshi
Keyword(s):  
Antibiotic Resistance ◽  
Oxygen Demand ◽  
Dairy Wastewater ◽  
Organic Load ◽  
Diffusion Method ◽  
Resistance Profile ◽  
Antibiotic Resistance Profile ◽  
Surrounding Environment ◽  
Before And After ◽  
Microbial Isolates

Objective: The objective of this study is to make sure biotreatment process used for treatment of dairy wastewater (DWW) is safe for human and its surrounding environment; microbes were evaluated for their antibiotic resistance profile against commonly prescribed antibiotics. Methods: Microbes were isolated using spread plating and streaking method and used to treat DWW. Reduction in organic load in DWW was determined by comparing physicochemical parameters (PCP) of DWW before and after treatment process. After selection of efficient microbial isolates, they were evaluated for their antibiotic resistance profile using antibiotic disc diffusion method. Results: In this work, 53 microbes were isolated from DWW, and these microbial isolates were screened for DWW degradation capacity by analyzing PCP. Four microbial isolates E3, E5, E11 (bacterial isolates) and F5 (fungal isolate) showed highest reduction in chemical oxygen demand (COD), biological oxygen demand (BOD), and dissolved oxygen (DO) were selected for profound degradation of DWW under optimized conditions. Efficient four microbial isolates individually performed better under anaerobic conditions by showing maximum reduction 84%, 75%, and 77% in COD, BOD, and DO, respectively. After 72 hrs of antibiotic susceptibility testing, E3 strain had shown 100%, E5 90%, E11 70%, and F5 80% susceptibility to antibiotics. Conclusion: The present study concluded that four microbial isolates had the potential of reducing the organic load of DWW along with lessor or negligible adverse effect on human or its surrounding environment and they appear to be most promising strains for treatment of DWW. 

Nanoantibiotic Formulations to Combat Antibiotic Resistance - Old Wine in a New Bottle

2020 ◽  
Vol 13 (3) ◽  
pp. 174-183 ◽  
Author(s):  
Rachna Rana ◽  
Rajendra Awasthi ◽  
Bhupesh Sharma ◽  
Giriraj T. Kulkarni
Keyword(s):  
Antibiotic Resistance ◽  
Large Scale ◽  
Bacterial Resistance ◽  
Drug Loading ◽  
Treatment Success ◽  
Physicochemical Characteristics ◽  
Practical Applications ◽  
Pathological Conditions ◽  
New Frontier ◽  
Improved Stability

: Antibiotic resistance is becoming one of the major obstacles to treatment success in various pathological conditions. Development process of a new antimicrobial agent is slow and difficult, whereas bacterial resistance is decreasing the arsenal of existing antibiotics. Therefore, there is a need to develop novel antibiotic formulations to combat the resistance of existing antibiotics. Nanoparticles are investigated as novel antibiotic formulation, but are often inefficient in practical applications. Nanotechnology presents a new frontier to overcome the issue of antibiotic resistance through the development of functionalized particles. Balance of physicochemical characteristics such as small particle size and high drug loading capacity along with improved stability are the challenges associated with large scale manufacturing of nanoantibiotic formulations. In the last 1-2 decades, a gradual increase in patents on nanoantibiotic formulations has been noted to address the resistance issues of antibiotic. The aim of this review is to consolidate recently-investigated nanoantibiotic formulations to combat antibiotic resistance.

Sign in / Sign up

Export Citation Format

Share Document