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Staphylococcus aureus is the most common cause of surgical site infections and its treatment is challenging due to the emergence of multi-drug resistant strains such as methicillin-resistant S. aureus (MRSA). Natural berry-derived compounds have shown antimicrobial potential, e.g., ellagitannins such as sanguiin H-6 and lambertianin C, the main phenolic compounds in Rubus seeds, have shown antimicrobial activity. The aim of this study was to evaluate the effect of sanguiin H-6 and lambertianin C fractionated from cloudberry seeds, on the MRSA growth, and as treatment of a MRSA biofilm development in different growth media in vitro and in vivo by using a murine wound infection model where sanguiin H-6 and lambertianin C were used to prevent the MRSA infection. Sanguiin H-6 and lambertianin C inhibited the in vitro biofilm development and growth of MRSA. Furthermore, sanguiin H-6 showed significant anti-MRSA effect in the in vivo wound model. Our study shows the possible use of sanguiin H-6 as a preventive measure in surgical sites to avoid postoperative infections, whilst lambertianin C showed no anti-MRSA activity.

The guanidine core has been one of the most studied functional groups in medicinal chemistry, and guanylation reactions are powerful tools for synthesizing this kind of compound. In this study, a series of five guanidine-core small molecules were obtained through guanylation reactions. These compounds were then evaluated against three different strains of Escherichia coli, one collection strain from the American Type Culture Collection (ATCC) of E. coli ATCC 35218, and two clinical extended-spectrum beta-lactamase (ESBL)-producing E. coli isolates (ESBL1 and ESBL2). Moreover, three different strains of Pseudomonas aeruginosa were studied, one collection strain of P. aeruginosa ATCC 27853, and two clinical multidrug-resistant isolates (PA24 and PA35). Among Gram-positive strains, three different strains of Staphylococcus aureus, one collection strain of S. aureus ATCC 29213, and two clinical methicillin-resistant S. aureus (MRSA1 and MRSA2) were evaluated. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) experiments were reported, and the drop plate (DP) method was used to determine the number of viable suspended bacteria in a known beaker volume. The results from this assessment suggest that guanidine-core small molecules hold promise as therapeutic alternatives for treating infections caused by clinical Gram-negative and Gram-positive bacteria, highlighting the need for further studies to explore their potential. The results from this assessment suggest that the chemical structure of CAPP4 might serve as the basis for designing more active guanidine-based antimicrobial compounds, highlighting the need for further studies to explore their potential.

Low- and middle-income countries bear a disproportionate burden of antimicrobial resistance and often lack adequate surveillance due to a paucity of microbiological studies. In this 2022 study, our goal was to contribute to a more precise antimicrobial treatment by understanding the prevalence of resistance in a rural environment, promoting antibiotic stewardship, and raising awareness about antimicrobial resistance. We assessed the prevalence of Multidrug-Resistant (MDR) and Extensively Drug-Resistant (XDR) Enterobacterales in clinical samples from 2905 patients being treated at Saint Dominic’s Hospital, Akwatia, in the countryside of the Eastern Region, Ghana, in the year 2022. To this purpose, the samples were cultured on agar plates prepared in the laboratory using purified Oxoid™ Thermo Scientific™ agar (Thermo Fisher Scientific; Waltham, MA, USA). Cystine Lactose Electrolyte-Deficient (CLED) agar was used for urine samples, while blood agar, chocolate agar, and MacConkey agar were used for the rest of the specimens tested (HVS, blood, BFA, sputum). Antimicrobial susceptibility was determined on site using the disc diffusion method (Kirby-Bauer test). MDR bacteria accounted for more than half (53.7%) of all microorganisms tested for three or more antibiotics and 37.3% of these were XDR. Multivariate regression analysis was performed to identify risk factors associated with acquiring MDR/XDR bacteria. The results showed an increased likelihood of MDR acquisition linked to being male (OR 2.39, p < 0.001 for MDR and OR 1.95, p = 0.027 for XDR), higher age (OR 1.01, p = 0.049 for MDR), non-sputum samples (OR 0.32, p = 0.009 for MDR), and urine samples (OR 7.46, p < 0.001 for XDR). These findings emphasize the urgency for surveillance and control of antimicrobial resistance; to this end, making accurate diagnostics, studying the microorganism in question, and conducting susceptibility testing is of the utmost importance.

Nanotechnology is a developing field that has boomed in recent years due to the multiple qualities of nanoparticles (NPs), one of which is their antimicrobial capacity. We propose that NPs anchored with 2-(dimethylamino)ethyl methacrylate (DMAEMA) have antibacterial properties and could constitute an alternative tool in this field. To this end, the antimicrobial effects of three quaternised NPs anchored with DMAEMA were studied. These NPs were later copolymerized using different methylmethacrylate (MMA) concentrations to evaluate their role in the antibacterial activity shown by NPs. Clinical strains of Staphylococcus aureus, S. epidermidis, S. lugdunensis and Enterococcus faecalis were used to assess antibacterial activity. The minimal inhibitory concentration (MIC) was determined at the different concentrations of NPs to appraise antibacterial activity. The cytotoxic effects of the NPs anchored with DMAEMA were determined in NIH3T3 mouse fibroblast cultures by MTT assays. All the employed NPs were effective against the studied bacterial strains, although increasing concentrations of the MMA added during the synthesis process diminished these effects without altering toxicity in cell cultures. To conclude, more studies with other copolymers are necessary to improve the antibacterial effects of NPs anchored with DMAEMA.

A cross-sectional study of microorganisms isolated from mid-stream urine samples obtained from 139 patients with suspected urinary tract infection (UTI) who presented leukocyturia was conducted from April to June 2019 at Saint Joseph Kitgum Hospital (Uganda). All microorganisms were identified by MALDI-TOF mass spectrometry in a laboratory in Spain. Antimicrobial susceptibility was determined on site using the disc diffusion method (Kirby–Bauer test) and these results were subsequently compared with those obtained in Spain using the Becton Dickinson Phoenix M50 device. The overall prevalence of UTI with bacterial growth was 64.0% (n = 89) (95% CI, 56.1–72.0), and 11 presented mixed infection. As a result, 100 microorganisms were isolated. The most common uropathogens were Enterococcus spp. (57%) and Escherichia coli (28%). Nitrofurantoin was the most effective drug (81.7% in Gram-positive and 87.3% in Gram-negative bacteria), followed by imipenem (94.2% and 74.5%, respectively). The highest resistance rates were observed for amoxicillin and ciprofloxacin (66.2% and 44.6%, respectively). Given the increasing trend toward antibiotic resistance, there is a need for bacteriological cultures and continuous surveillance of uropathogen antibiotic susceptibility. Use of amoxicillin and ciprofloxacin as empirical treatments for UTIs should be discontinued in Uganda. The findings of this study may be useful for clinicians, as they may improve empirical treatment.