scholarly journals Synthesis of Ribose-Coated Copper-Based Metal–Organic Framework for Enhanced Antibacterial Potential of Chloramphenicol against Multi-Drug Resistant Bacteria

Antibiotics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1469
Author(s):  
Haseena ◽  
Adnan Khan ◽  
Iqra Ghaffar ◽  
Roua S. Baty ◽  
Mohamed M. Abdel-Daim ◽  
...  

The rise in bacterial resistance to currently used antibiotics is the main focus of medical researchers. Bacterial multidrug resistance (MDR) is a major threat to humans, as it is linked to greater rates of chronic disease and mortality. Hence, there is an urgent need for developing effective strategies to overcome the bacterial MDR. Metal–organic frameworks (MOFs) are a new class of porous crystalline materials made up of metal ions and organic ligands that can vary their pore size and structure to better encapsulate drug candidates. This study reports the synthesis of ribose-coated Cu-MOFs for enhanced bactericidal activity of chloramphenicol (CHL) against Escherichia coli (resistant and sensitive) and MDR Pseudomonas aeruginosa. The synthesized Cu-MOFs were characterized with DLS, FT-IR, powder X-ray diffraction, scanning electron microscope, and atomic force microscope. They were further investigated for their efficacy against selected bacterial strains. The synthesized ribose-coated Cu-MOFs were observed as spherical shape structure with the particle size of 562.84 ± 13.42 nm. CHL caused the increased inhibition of E. coli and MDR P. aeruginosa with significantly reduced MIC and MBIC values after being encapsulated in ribose-coated Cu-MOFs. The morphological analysis of the bacterial strains treated with ribose-coated CHL-Cu-MOFs showed the complete morphological distortion of both E. coli and MDR P. aeruginosa. Based on the results of the study, it can be suggested that ribose-coated Cu-MOFs may be an effective alternate candidate to overcome the MDR and provide new perspective for the treatment of MDR bacterial infections.

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 824
Author(s):  
Hala Nehme ◽  
Helena Ayde ◽  
Dany El Obeid ◽  
Jean Marc Sabatier ◽  
Ziad Fajloun

Bacterial resistance has become a worrying problem for human health, especially since certain bacterial strains of Escherichia coli (E. coli) can cause very serious infections. Thus, the search for novel natural inhibitors with new bacterial targets would be crucial to overcome resistance to antibiotics. Here, we evaluate the inhibitory effects of Apis mellifera bee venom (BV-Am) and of its two main components -melittin and phospholipase A2 (PLA2)- on E. coli F1F0-ATPase enzyme, a crucial molecular target for the survival of these bacteria. Thus, we optimized a spectrophotometric method to evaluate the enzymatic activity by quantifying the released phosphate from ATP hydrolysis catalyzed by E. coli F1F0-ATPase. The protocol developed for inhibition assays of this enzyme was validated by two reference inhibitors, thymoquinone (IC50 = 57.5 μM) and quercetin (IC50 = 30 μM). Results showed that BV-Am has a dose-dependent inhibitory effect on E. coli F1F0-ATPase with 50% inhibition at 18.43 ± 0.92 μg/mL. Melittin inhibits this enzyme with IC50 = 9.03 ± 0.27 µM, emphasizing a more inhibitory effect than the two previous reference inhibitors adopted. Likewise, PLA2 inhibits E. coli F1F0-ATPase with a dose-dependent effect (50% inhibition at 2.11 ± 0.11 μg/mL) and its combination with melittin enhanced the inhibition extent of this enzyme. Crude venom and mainly melittin and PLA2, inhibit E. coli F1F0-ATPase and could be considered as important candidates for combating resistant bacteria.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1896
Author(s):  
Farhan Alshammari ◽  
Bushra Alshammari ◽  
Afrasim Moin ◽  
Abdulwahab Alamri ◽  
Turki Al Hagbani ◽  
...  

Ceftriaxone has been a part of therapeutic regime for combating some of the most aggressive bacterial infections in the last few decades. However, increasing bacterial resistance towards ceftriaxone and other third generation cephalosporin antibiotics has raised serious clinical concerns especially due to their misuse in the COVID-19 era. Advancement in nanotechnology has converted nano-therapeutic vision into a plausible reality with better targeting and reduced drug consumption. Thus, in the present study, gold nanoparticles (GNPs) were synthesized by using ceftriaxone antibiotic that acts as a reducing as well as capping agent. Ceftriaxone-loaded GNPs (CGNPs) were initially characterized by UV-visible spectroscopy, DLS, Zeta potential, Electron microscopy and FT-IR. However, a TEM micrograph showed a uniform size of 21 ± 1 nm for the synthesized CGNPs. Further, both (CGNPs) and pure ceftriaxone were examined for their efficacy against Escherichia coli, Staphylococcus aureus, Salmonella abony and Klebsiella pneumoniae. CGNPs showed MIC50 as 1.39, 1.6, 1.1 and 0.9 µg/mL against E. coli, S. aureus, S. abony and K. pneumoniae, respectively. Interestingly, CGNPs showed two times better efficacy when compared with pure ceftriaxone against the tested bacterial strains. Restoring the potential of unresponsive or less efficient ceftriaxone via gold nanoformulations is the most alluring concept of the whole study. Moreover, applicability of the findings from bench to bedside needs further validation.


2021 ◽  
Author(s):  
Inga S. Shchelik ◽  
Karl Gademann

Antibiotic-resistant and biofilm-associated infections constitute a rapidly growing issue. The last resort antibiotic vancomycin is under threat, due to the increasing appearance of vancomycin resistant bacteria as well as the formation of biofilms. Herein, we report a series of novel vancomycin derivatives carrying thiol- and disulfide-containing moieties. The new compounds exhibited enhanced antibacterial activity against a broad range of bacterial strains, including vancomycin resistant microbes and Gram-negative bacteria. Moreover, all obtained derivatives demonstrated improved antibiofilm formation activity against VanB resistant Enterococcus compared to vancomycin. This work established a promising strategy for combating drug-resistant bacterial infections or disrupting biofilm formation and advances the knowledge on structural optimization of antibiotics with sulfur-containing modifications.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 871
Author(s):  
Mohammed F. Aldawsari ◽  
El-Sayed Khafagy ◽  
Ahmed Al Saqr ◽  
Ahmed Alalaiwe ◽  
Hisham A. Abbas ◽  
...  

The bacterial resistance development due to the incessant administration of antibiotics has led to difficulty in their treatment. Natural adjuvant compounds can be co-administered to hinder the pathogenesis of resistant bacteria. Sotolon is the prevailing aromatic compound that gives fenugreek its typical smell. In the current work, the anti-virulence activities of sotolon on Pseudomonas aeruginosa have been evaluated. P. aeruginosa has been treated with sotolon at sub-minimum inhibitory concentration (MIC), and production of biofilm and other virulence factors were assessed. Moreover, the anti-quorum sensing (QS) activity of sotolon was in-silico evaluated by evaluating the affinity of sotolon to bind to QS receptors, and the expression of QS genes was measured in the presence of sotolon sub-MIC. Furthermore, the sotolon in-vivo capability to protect mice against P. aeruginosa was assessed. Significantly, sotolon decreased the production of bacterial biofilm and virulence factors, the expression of QS genes, and protected mice from P. aeruginosa. Conclusively, the plant natural substance sotolon attenuated the pathogenicity of P. aeruginosa, locating it as a plausible potential therapeutic agent for the treatment of its infections. Sotolon can be used in the treatment of bacterial infections as an alternative or adjuvant to antibiotics to combat their high resistance to antibiotics.


2010 ◽  
Vol 54 (12) ◽  
pp. 5193-5200 ◽  
Author(s):  
Victoire de Lastours ◽  
Françoise Chau ◽  
Florence Tubach ◽  
Blandine Pasquet ◽  
Etienne Ruppé ◽  
...  

ABSTRACT The important role of commensal flora as a natural reservoir of bacterial resistance is now well established. However, whether the behavior of each commensal flora is similar to that of other floras in terms of rates of carriage and risk factors for bacterial resistance is unknown. During a 6-month period, we prospectively investigated colonization with fluoroquinolone-resistant bacteria in the three main commensal floras from hospitalized patients at admission, targeting Escherichia coli in the fecal flora, coagulase-negative Staphylococcus (CNS) in the nasal flora, and α-hemolytic streptococci in the pharyngeal flora. Resistant strains were detected on quinolone-containing selective agar. Clinical and epidemiological data were collected. A total of 555 patients were included. Carriage rates of resistance were 8.0% in E. coli, 30.3% in CNS for ciprofloxacin, and 27.2% in streptococci for levofloxacin; 56% of the patients carried resistance in at least one flora but only 0.9% simultaneously in all floras, which is no more than random. Risk factors associated with the carriage of fluoroquinolone-resistant strains differed between fecal E. coli (i.e., colonization by multidrug-resistant bacteria) and nasal CNS (i.e., age, coming from a health care facility, and previous antibiotic treatment with a fluoroquinolone) while no risk factors were identified for pharyngeal streptococci. Despite high rates of colonization with fluoroquinolone-resistant bacteria, each commensal flora behaved independently since simultaneous carriage of resistance in the three distinct floras was uncommon, and risk factors differed. Consequences of environmental selective pressures vary in each commensal flora according to its local specificities (clinical trial NCT00520715 [http://clinicaltrials.gov/ct2/show/NCT00520715 ]).


Author(s):  
Trâm Quế Anh

TÓM TẮT Đặt vấn đề: Xác định đúng căn nguyên gây NKĐTN và mức độ kháng kháng sinh của các vi khuẩn sẽ giúp cho việc điều trị có hiệu quả, giảm được chi phí điều trị, hạn chế sự gia tăng vi khuẩn đề kháng kháng sinh. Đối tượng và phương pháp nghiên cứu: Các chủng VK gây nhiễm khuẩn đương tiết niệu phân lập được tại bệnh viện Hữu nghị Đa khoa Nghệ An từ 1/2020 đến 12/2020. Thiết kế nghiên cứu: Cắt ngang mô tả. Kết quả: Phân lập được 473 chủng vi khuẩn gây NKĐTN, trong đó, E. coli 38,48%; P. aeruginosa 14,15; Enterococcus sp 10,57; K. pneumoniae 13,32%. E. coli: kháng các kháng sinh Cephalosporine, Quinolones từ 56,7 - 63,8%, Carbapenem 4,5 - 6,2%, sinh ESBL 49,4%. P. aeruginosa: đã kháng các kháng sinh thử nghiệm từ 59,1 - 69,2%. Enterococcus sp: kháng với các kháng sinh nhóm Quinolone 73,5%, kháng Vancomycin 8,3%; Chưa ghi nhận đề kháng Linezolid. K. pneumoniae: kháng nhóm Cephalosporin, Quinolone từ 66,7 - 74,6%, đề kháng với Carbapenem từ 46,0 - 50,8%. Kết luận: Các vi khuẩn gây nhiễm khuẩn tiết niệu thường gặp là: E. coli, P. aeruginosa, Enterococcus sp. K. pneumoniae. Các vi khuẩn phân lập được đã đề kháng với nhiều kháng sinh thường dùng với các mức độ khác nhau. Xuất hiện các chủng vi khuẩn Gram âm kháng Carbapenem, Gram dương kháng Vancomycin. Từ khóa: Nhiễm khuẩn tiết niệu, E.coli, Klebsiella, P.aeruginosa, Enterococcus sp ABSTRACT RESEARCH OF ANTIBIOTICS RESISTANCE OF BACTERIA STRAINS CAUSING URINARY TRACT INFECTIONS ISOLATED AT NGHEAN FRIENDSHIP GENERAL HOSPITAL Background: The good identification of UTI microorganism and their antimicrobial susceptibility would promote the effective treatment, reduce the cost as well as the emergence of drug resistant bacteria. Methods: Bacterial strains causing urinary tract infections were isolated at Nghe An Friendship General Hospital from 1/2020 to 12/2020. Study design: Descriptive cross section. Results: 473 bacterial strains causing UTIs were isolated, in which, E. coli 38.48%; P. aeruginosa 14.15; Enterococcus sp 10.57; K. pneumoniae 13.32%. E. coli: resistant to Cephalosporin antibiotics, Quinolones from 56.7 - 63.8%, Carbapenem 4.5 - 6.2%, producing ESBL 49.4%. P. aeruginosa: was resistant to the tested antibiotics from 59.1 - 69.2%. Enterococcus sp: resistant to Quinolone antibiotics 73.5%, resistant to Vancomycin 8.3%; Linezolid resistance has not been recorded. K. pneumoniae: resistant to Cephalosporin, Quinolone from 66.7 - 74.6%, resistant to Carbapenem from 46.0 - 50.8%. Conclusion: Common bacteria causing urinary tract infections are: E. coli, P. aeruginosa, Enterococcus sp. K. pneumoniae. The isolates were resistant to many commonly used antibiotics to varying degrees. Occurrence of strains of Gram - negative bacteria resistant to Carbapenem, Gram - positive resistant to Vancomycin. Keywords: Urinary Tract infections, E. coli, Klebsiella, P. aeruginosa, Enterococcus sp.


Antibiotics ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 98 ◽  
Author(s):  
Eunice Mgbeahuruike ◽  
Pia Fyhrquist ◽  
Heikki Vuorela ◽  
Riitta Julkunen-Tiitto ◽  
Yvonne Holm

Piper guineense is a food and medicinal plant commonly used to treat infectious diseases in West-African traditional medicine. In a bid to identify new antibacterial compounds due to bacterial resistance to antibiotics, twelve extracts of P. guineense fruits and leaves, obtained by sequential extraction, as well as the piperine and piperlongumine commercial compounds were evaluated for antibacterial activity against human pathogenic bacteria. HPLC-DAD and UHPLC/Q-TOF MS analysis were conducted to characterize and identify the compounds present in the extracts with promising antibacterial activity. The extracts, with the exception of the hot water decoctions and macerations, contained piperamide alkaloids as their main constituents. Piperine, dihydropiperine, piperylin, dihydropiperylin or piperlonguminine, dihydropiperlonguminine, wisanine, dihydrowisanine and derivatives of piperine and piperidine were identified in a hexane extract of the leaf. In addition, some new piperamide alkaloids were identified, such as a piperine and a piperidine alkaloid derivative and two unknown piperamide alkaloids. To the best of our knowledge, there are no piperamides reported in the literature with similar UVλ absorption maxima and masses. A piperamide alkaloid-rich hexane leaf extract recorded the lowest MIC of 19 µg/mL against Sarcina sp. and gave promising growth inhibitory effects against S. aureus and E. aerogenes as well, inhibiting the growth of both bacteria with a MIC of 78 µg/mL. Moreover, this is the first report of the antibacterial activity of P. guineense extracts against Sarcina sp. and E. aerogenes. Marked growth inhibition was also obtained for chloroform extracts of the leaves and fruits against P. aeruginosa with a MIC value of 78 µg/mL. Piperine and piperlongumine were active against E. aerogenes, S. aureus, E. coli, S. enterica, P. mirabilis and B. cereus with MIC values ranging from 39–1250 µg/mL. Notably, the water extracts, which were almost devoid of piperamide alkaloids, were not active against the bacterial strains. Our results demonstrate that P. guineense contains antibacterial alkaloids that could be relevant for the discovery of new natural antibiotics.


2020 ◽  
Vol 17 ◽  
pp. 00103
Author(s):  
Oleg Fomenko ◽  
Evgeny Mikhailov ◽  
Nadezhda Pasko ◽  
Svetlana Grin ◽  
Andrey Koshchaev ◽  
...  

The emergence of antibiotic-resistant bacteria is considered a serious problem. The resistance of bacteria against antimicrobial substances becomes important in the repair systems for damage to DNA and RNA molecules. The role of the antioxidant system in the development of bacterial resistance against antibiotics is not yet practically studied. The article studied the expression regulation of the genes of antioxidant enzymes and enzymes involved in the genetic information in E. coli cells with the antibiotic resistance against apramycin and cefatoxime. The study was conducted on bacterial cells resistant against these two antibiotics. The genes blaOXA-1, blaSHV, blaTEM, mdtK, aadA1, aadA2, sat, strA, blaCTX, blaPER-2, tnpA, tnpR, intC1 and intC1c were identified in bacterial cell case. This indicates the presence of plasmids in bacteria with these genes, which provide bacterial resistance to apramycin and cefatoxime. It was established that during the formation of cefotaxime resistance, there was a sharp increase in the expression of the Cu, Zn superoxide dismutase gene: in comparison with the control group, the representation of its transcripts increased 141.04 times for cefotoxime and 155.42 times for apramycin. It has been established that during the formation of resistance to the studied antibiotics in E. coli, an increase in the expression of the end4 and end3 genes is observed. There is tendency toward an increase in the number of transcripts of the pol3E gene observed in the formation of resistance against cefotaxime and apromycin.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Saleh A. Ahmed ◽  
Damayanti Bagchi ◽  
Hanadi A. Katouah ◽  
Md. Nur Hasan ◽  
Hatem M. Altass ◽  
...  

AbstractIn this work, we have successfully synthesized a bimetallic (Zinc and Cobalt) Zeolitic Imidazolate Framework (Zn50Co50-ZIF), a class in a wider microporous Metal-Organic Framework (MOF) family. The synthesized nanostructures maintain both water stability like ZIF-8 (solely Zn containing) and charge transfer electronic band in the visible optical spectrum as ZIF-67 (solely Co containing). Crystal structure from XRD, high resolution transmission electron microscopy (HRTEM) followed by elemental mapping (EDAX) confirm structural stability and omnipresence of the metal atoms (Zn and Co) across the nanomaterial with equal proportion. Existence of charge transfer state consistent with ZIF67 and intact ultrafast excited state dynamics of the imidazolate moiety in both ZIF-8 and ZIF-67, is evidenced from steady state and time resolved optical spectroscopy. The thermal and aqueous stabilities of Zn50Co50-ZIF are found to be better than ZIF-67 but comparable to ZIF-8 as evidenced by solubility, scanning electron microscopy (SEM) and XRD studies of the material in water. We have evaluated the photoinduced ROS generation by the mixed ZIF employing dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay. We have also explored the potentiality of the synthesized material for the alternate remediation of methicillin resistant Staphylococcus aureus (MRSA) infection through the photoinduced reactive oxygen species (ROS) generation and methylene blue (MB) degradation kinetics.


Sign in / Sign up

Export Citation Format

Share Document