BACKGROUND AND OBJECTIVES

Staphylococcus aureus poses a significant public health threat globally, where both community and hospital-acquired infections are prevalent. The escalating antimicrobial resistance highlights the urgent need for alternative therapies. Hence, traditional medicine using plant extracts offers a potential avenue for novel antibacterial agents. This systematic review aimed to evaluate the existing literature on the antibacterial properties of Philippine plants against S. aureus to provide focus on drug development of a plant-derived antibacterial for this pathogen.

METHODS

Following PRISMA guidelines, a comprehensive search was conducted in PubMed/Medline, SCOPUS, and Herdin databases. Inclusion criteria encompassed in-vitro studies evaluating the antibacterial activity of crude plant extracts sourced from Philippines plants against S. aureus. Data extraction and quality assessment were performed independently by two reviewers, with discrepancies resolved by the third and fourth reviewers.

RESULTS

Of the 413 initial studies identified, nine (9) met the eligibility criteria. The highest zone of inhibition was demonstrated by Lippia micromera L. leaf essential oil at 26.3±1.5 mm, while moderate antibacterial activity was shown by essential oils from Alpinia elegans, Piper quinqueangulatum, and Alpinia cumingii at MIC values of 512 µg/mL, 512 µg/mL, and 1,024 µg/mL, respectively. Other Philippine plants showed a wide range of activity, with MIC values between 50 ?g/mL and 25 mg/mL, MBC values from 78 to 5000 ?g/mL, and ZOI ranging from 5 to 38 mm. However, the overall quality of evidence in these other studies are compromised by bias and incomplete reporting.

CONCLUSION

Leaf essential oils from Alpinia elegans, Piper quinqueangulatum, and Alpinia cumingii demonstrated moderate antibacterial activity against S. aureus. Additionally, the essential oils of Lippia micromera L., Plectranthus amboinicus Lour. Spreng, and Cymbopogon citratus exhibited antibacterial activity against both S. aureus and Methicillin-resistant S. aureus (MRSA) in disk diffusion assays. Majority of the studies gathered had high risk of bias according to the quality assessment criteria tool used in the study. Thus, this systematic review also emphasizes the need for improved methodological rigor on reported in-vitro antibacterial studies.

Staphylococcus ; Staphylococcus Aureus ; Systematic Review

A singular medical incident can alert health officials to an emerging, if not widespread, but possibly undetected publichealth concern.

Our issue contains a remarkable case of a ruptured hepatic abscess in a 3-year-old, which turned out to be MethicillinresistantStaphylococcus aureus (MRSA) by authors Torrico and Tarnate.The concern is that the infection is communityacquired,and the patient was immunocompetent. This sounds the alarm for the occurrence of antimicrobial resistance (AMR)in the communities and calls for a response from health authorities to investigate, analyze, and propose solutions for sucha sentinel event.

We need to support these efforts and, in this issue, we publish such work from our investigators. Antimicrobial resistanceis an urgent global health concern.The impact is magnified in low to middle-income countries where health risks are high,and health infrastructure is weak. Thus, it is imperative that determinants of AMR are scrutinized to allow crafting offocused strategies to combat the problem.

The article by Dela Cruz and Hernandez on the prevalence and practices of antibiotic misuse among adult residents ofRodriguez, Rizal, contributes to this analysis.The paper reveals a disturbing prevalence of self-medication and identifiesbarriers to accessing proper health education and care. This is a global problem, and the paper from Brazil relates the observationof community pharmacists of antibiotic misuse to the rise of antimicrobial resistance.

Dela Cruz and Hernandez recommend stricter antibiotic regulation, and this falls squarely into the scope of concernof another article in this issue, the “Research Needs in Philippine Pharmaceutical Sciences: A Qualitative Perspective fromRegulatory and Clinical Research Sectors of the Pharmaceutical Industry” by Pena and co-authors.Interestingly, whiledrug registration and clinical trials were the focus of the paper, it may be a desired expansion of the regulatory reach of theindustry to temper the use of antibiotics as it is being dispensed to end users.Antimicrobial stewardship involves ethicalpromotion of use and equitable access to appropriate treatment, and these concerns require the responsible participation of thepharmaceutical industry.

Health challenges are complex. The analysis of these challenges requires surveillance of literature for sentinel events, useof community-based research to investigate phenomena, and system mapping to identify relevant sectors to improve strategyand to involve relevant stakeholders.

We support this type of scholarship, which seeks to expand the focus from isolated clinical interventions towards placinga spotlight on relevant work that will lead to impactful reform of broad health ecosystems.

Human ; Child Preschool: 2-5 Yrs Old ; Therapeutics ; Staphylococcus Aureus ; Pharmaceutical Preparations ; Research Personnel ; Health Services Needs And Demand ; Methicillin-resistant Staphylococcus Aureus ; Antimicrobial Stewardship

Methicillin-resistantStaphylococcus aureus(MRSA) is an uncommon etiologic agent of hepatic abscess in children, particularly those without an underlying immunocompromised condition.

We describe a rare case of community-acquired MRSA (CA-MRSA) hepatic abscess with rupture into the anterior abdominal wall in an otherwise healthy 3-year-old Filipino male, manifesting as a one-week history of an enlarging epigastric mass accompanied by abdominal pain and fever. He was treated noninvasively with ciprofloxacin (intravenous at 10 mg/kg every 12 hours for 14 days followed by oral at 15 mg/kg every 12 hours for 28 days), and clindamycin (intravenous at 10 mg/kg every 6 hours for 14 days followed by oral at 10 mg/kg every 6 hours for 28 days), resulting in the resolution of the hepatic abscess and its associated symptoms.

CA-MRSA hepatic abscess is extremely rare in immunocompetent children, and an appropriate diagnostic approach involving imaging and culture studies is crucial in its diagnosis and management.

Human ; Child Preschool: 2-5 Yrs Old ; Therapeutics ; Staphylococcus Aureus ; Staphylococcus ; Residence Characteristics ; Research Report ; Dihydrotachysterol

Purulent pericarditis is a rare occurrence in the era of modern antibiotics. It is most often caused by organisms such as Staphylococcus aureus, Streptococcus pneumoniae, Viridans streptococci, Haemophilus influenzae and anaerobic bacteria with Streptococcus pyogenes (S.pyogenes) being a possible, though very uncommon etiology. This case represents an occurrence of S. pyogenes pericarditis in an apparently healthy female with no known immunocompromising condition. A 37-year-old female, married, real estate agent with no comorbidities came in for chest pain radiating to the upper back, relieved with leaning forward. Cardiac biomarker was normal, ECG demonstrated diffuse ST-segment elevation and PR segment depression, while imaging showed lobar pneumonia. Blood tests showed leukocytosis with neutrophilic predominance and workup for immunocompromised state was negative. The 2D echo showed large pericardial effusion with tamponade physiology. An urgent pericardiocentesis was done. Cultures grew Streptococcus pyogenes confirming the diagnosis of acute purulent pericarditis. Daily drainage of pericardial effusion, colchicine, ibuprofen was initiated together with antibiotics and the patient had resolution of pericardial effusion. Acute pyogenic pericarditis with cardiac tamponade is a rare but serious condition that requires prompt recognition and intervention. Early diagnosis, through a combination of clinical suspicion, ECG and echocardiography is crucial for initiating timely treatment.

Human ; Female ; Adult: 25-44 Yrs Old ; Viridans Streptococci ; Streptococcus Pyogenes ; Streptococcus Pneumoniae ; Staphylococcus Aureus ; Streptococcal Infections ; Electrocardiography ; Echocardiography ; Early Diagnosis

INTRODUCTION

Burn wound infection is a significant risk factor in the morbidity and mortality of burn wound patients. Previous studies in our institution showed bacterial colonization in burn patients seen beyond 24 hours post-injury. The microbiological profile of burn wounds seen within 24 hours, including the presence and risk factors for wound colonization, has not been determined in our Burn Center.

OBJECTIVES

To identify the presence and risk factors for burn wound colonization in burn patients seen less than 24 hours after injury and determine the microbiological profile and antibiotic susceptibility patterns in colonized burn wounds.

METHODS

One hundred eighty-nine burn patients who were seen at and admitted to the UP Philippine General Hospital ATR Burn Center within 24 hours of the burn injury from June 2021 until July 2023 were included in the study. Demographic and clinical data were collected upon admission. A total of 635 swab samples were collected from 189 patients and were sent for identification of aerobic organisms by standard culture methods and antibiotic sensitivity tests using the Kirby-Bauer disc diffusion method. Association of patient characteristics (area of injury, time received post-injury, previous hospital care, place of injury, percent burn injury, etiology, mode of transport, and type of dressing prior to admission) were determined using Chi square test of independence.

RESULTS

Out of 189 burn patients seen within 24 hours after injury included in the study, 58.73% (n = 111) of patients, and 49.29% (n = 313) of swabs showed bacterial colonization. Burn wound colonization was associated with area of injury/body region (χ2 5 = 16.29, p = .0061), time received post-injury (χ2 3 = 24.62, p < 0.0001, post hoc Fisher’s test for 6-12 hours vs. within the first 6 hours: p < 0.0001), place of burn injury (χ2 2 = 18.17, p = 0.0001, post hoc Fisher’s test work vs. home: p = 0.0006, work vs. outdoors: p = 0.0015), percent burn injury (χ2 4 = 21.40, p = 0.0003, post hoc Fisher’s test 25-49% vs. 0-9%: p = 0.004, 50-75% vs. 0-9%: p = 0.002), and etiology of burn injury (χ2 2 = 37.05, p < 0.0001, post hoc Fisher’s test scald vs. flame: p = 0.0012, electrical vs. flame: p < .0001). From 313 positive samples, 357 isolates were identified. Staphylococcus (58.8%) was the most common organism isolated. It was noted that out of the total isolates, 15 (4.2%) were identified to be methicillin-resistant S. aureus (MRSA) while 5 isolates (1.4%) were methicillin-resistant S. epidermidis (MRSE). Streptococcus (10.4%) and Acinetobacter (6.2%) were the second and third most common organisms, respectively. Other groups identified were Aeromonas, Bacillus, Enterobacter, Pseudomonas, Klebsiella, and diphtheroids. Frequency of bacterial isolates differed across body regions, time received post-injury, percent burn injury, and etiology of burn injury. Resistance to one antibiotic was observed in 36.84%, 6.25%, and 63.64% of Staphylococcus, Streptococcus, and Acinetobacter isolates tested, respectively. Resistance to more than 1 antibiotic was observed in 48.68% of Staphylococcus isolates and 50.0% of Streptococcus isolates tested. Among the 51 S. aureus isolates, 29.1% were methicillin-resistant S. aureus (MRSA).

CONCLUSION

In burn patients seen within 24 hours after injury, about half of burn wounds and more than half of patients showed the presence of microbial growth. Potential risk factors for positive microbial growth in a burn wound during this timeframe were area of injury/ body region, place of injury, time received post-injury, percent TBSA burn, and etiology of burn injury. The most common isolate was Staphylococcus spp. More than half of Staphylococcus isolates showed antibiotic resistance, with a significant number showing multidrug resistance. More than a quarter of S. aureus isolates were methicillin-resistant S. aureus (MRSA). These results suggest that bacterial isolates can colonize burn wounds even within 24 hours post-injury and may exhibit antibiotic resistance.

Human ; Burns ; Wounds And Injuries ; Wound Infection ; Methicillin ; Klebsiella ; Methicillin-resistant Staphylococcus Aureus ; Drug Resistance, Multiple

Given the increasing concern regarding antibacterial resistance, the antimicrobial properties of naphthoquinones have recently attracted significant attention. While 1,4-naphthoquinone and its derivatives have been extensively studied, the antibacterial properties of 5,8-dihydroxy-1,4-naphthoquinone derivatives remain relatively unexplored. This study presents a comprehensive in vitro and in vivo analysis of the antibacterial activity of 35 naturally sourced and chemically synthesized derivatives of 5,8-dihydroxy-1,4-naphthoquinone. Kirby-Bauer antibiotic testing identified three compounds with activity against methicillin-resistant Staphylococcus aureus (MRSA), with one compound (PNP-02) demonstrating activity comparable to vancomycin in minimum inhibitory concentration, minimum bactericidal concentration (MBC), and time-kill assays. Microscopic and biochemical analyses revealed that PNP-02 adversely affects the cell wall and cell membrane of MRSA. Mechanistic investigations, including proteomic sequencing analyses, Western blotting, and RT-qPCR assays, indicated that PNP-02 compromises cell membrane integrity by inhibiting arginine biosynthesis and pyrimidine metabolism pathways, thereby increasing membrane permeability and inducing bacterial death. In an in vivo mouse model of skin wound healing, PNP-02 exhibited antibacterial efficacy similar to vancomycin. The compound demonstrated low toxicity to cultured human cells and in hemolysis assays and remained stable during serum incubation. These findings suggest that PNP-02 possesses promising bioactivity against MRSA and represents a potential novel antibacterial agent.
Methicillin-Resistant Staphylococcus aureus/genetics* ; Anti-Bacterial Agents/chemistry* ; Naphthoquinones/administration & dosage* ; Animals ; Microbial Sensitivity Tests ; Mice ; Humans ; Staphylococcal Infections/microbiology* ; Molecular Structure

OBJECTIVES: Calcium silicate (CSO) is modified to give it photothermal antibacterial properties. Its application potential in tooth mineralization and oral antibacterial is evaluated. METHODS: Based on defect-engineering modification strategy, a series of CSO-T samples (CSO-300, CSO-400, CSO-500, CSO-600) was obtained by introducing oxygen vacancy into CSO through thermal reduction using sodium borohydride. The samples were tested using scanning electron microscopy (SEM), X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet near-infrared absorption spectroscopy, and infrared thermography. The powder samples with the best photothermal performance and the most suitable material concentration (CSO-500, 500 μg/mL) were selected for subsequent experiments. High resolution transmission electron microscopy was used to analyze the microstructure and morphology of the sample, and MTT assay and Calcein AM/PI live/dead cell staining were used to evaluate the toxicity and compatibility of the sample to human oral keratinocytes. Escherichia coli and Staphylococcus aureus were selected for photothermal antibacterial experiments to evaluate their in vitro antibacterial performance. SEM, energy dispersive spectrometer, and micro Vickers hardness tester were used to evaluate the ability of materials to induce in vitro remineralization of detached teeth. RESULTS: Oxygen vacancies changed the crystal type and lattice spacing of CaSiO₃, broadened the light-absorption range, and gave it a good photothermal conversion ability in response to near infrared. Invitro experiments showed that the modified CaSiO₃ could promote the formation of hydroxyapatite on the tooth surface, thereby promoting the remineralization of teeth and improving the teeth hardness. Moreover, it had photothermal antibacterial properties and no cytotoxicity. CONCLUSIONS Defect-modified black calcium silicate has multiple functions, such as promoting tooth remineralization and photothermal bacteriostatic. When combined with the infrared luminescent toothbrush, it can simply and effectively treat tooth enamel erosion and oral bacteriostatic diseases caused by the excessive consumption of carbonated beverages and other daily bad living habits. This combination is expected to achieve the synergic treatment effect of tooth remineralization and oral bacteriostatic through daily cleaning is expected.
Calcium Compounds/pharmacology* ; Silicates/pharmacology* ; Humans ; Staphylococcus aureus/drug effects* ; Tooth Remineralization ; Escherichia coli/drug effects* ; Anti-Bacterial Agents/pharmacology* ; Keratinocytes/drug effects* ; Microscopy, Electron, Scanning

OBJECTIVES: This study aims to investigate the impact of glutathione S-transferase (GST) on the environmental adaptability of Streptococcus mutans (S. mutans). METHODS: A GST knockout strain ΔgsT was constructed. Transcriptomic sequencing was performed to analyze the gene expression differences between the wild-type S. mutans UA159 and its GST knockout strain ΔgsT. Comprehensive functional assessments, including acid tolerance assays, hydrogen peroxide challenge assays, nutrient limitation growth assays, and fluorescence in situ hybridization, were conducted to evaluate the acid tolerance, antioxidant stress resistance, growth kinetics, and interspecies competitive ability of ΔgsT within plaque biofilms. RESULTS: Compared with the wild-type S. mutans, 198 genes in ΔgsT were significantly differentially expressed and enriched in pathways related to metabolism, stress response, and energy homeostasis. The survival rate of ΔgsT in acid tolerance assays was markedly reduced (P<0.01). After 15 min of hydrogen peroxide challenge, the survival rate of ΔgsT decreased to 38.12% (wild type, 71.75%). Under nutrient-limiting conditions, ΔgsT exhibited a significantly lower final OD₆₀₀ value than the wild-type strain (P<0.05). In the biofilm competition assays, the proportion of S. mutans ΔgsT in the mixed biofilm (8.50%) was significantly lower than that of the wild type (16.89%) (P<0.05). CONCLUSIONS GST enhances the acid resistance, oxidative stress tolerance, and nutrient adaptation of S. mutans by regulating metabolism-related and stress response-related genes.
Streptococcus mutans/enzymology* ; Biofilms ; Glutathione Transferase/physiology* ; Adaptation, Physiological ; Hydrogen Peroxide/pharmacology* ; Gene Expression Regulation, Bacterial ; Oxidative Stress ; Metabolic Reprogramming

One of the technical bottlenecks limiting the high yield of 1,4-butanediamine is the insufficient tolerance of strains to 1,4-butanediamine. Enhancing the tolerance of strains to 1,4-butanediamine is therefore a primary challenge that needs to be addressed for the construction of strains with high yields of 1,4-butanediamine. Staphylococcus pasteuri 326180 exhibits exceptional tolerance to high-concentration 1,4-butanediamine, serving as both an ideal model for studying the mechanism underlying the 1,4-butanediamine tolerance and a novel host for constructing strains capable of efficiently producing 1,4-butanediamine. However, for both the research on the tolerance mechanism and the modification of chassis strains, gene editing of S. pasteuri needs to be carried out at the molecular level. The research objective of this paper is to establish a genetic manipulation system for S. pasteuri, laying foundation for subsequent studies on tolerance mechanism and the modification of chassis strains. This study systematically optimized the electroporation conditions, including key parameters such as the growth phase of cells, electric field strength, electroporation buffer, and recovery medium, successfully establishing an electroporation method for S. pasteuri. Additionally, we constructed the gene editing plasmid pCpfOA by replacing the resistance expression cassette, optimized the selection markers for gene editing, and finally established a CRISPR/Cpf1-based gene editing technology for S. pasteuri, achieving an editing efficiency of 90%. The genetic manipulation system of S. pasteuri established in this study provides technical support for research into the tolerance mechanism of this bacterium and the genetic modification of chassis strains.
Staphylococcus/drug effects* ; Gene Editing/methods* ; Electroporation/methods* ; Plasmids/genetics* ; CRISPR-Cas Systems ; Genetic Engineering/methods*

BACKGROUND AND OBJECTIVE

The emergence of antimicrobial resistance (AMR) poses a significant global health threat, with developing countries such as the Philippines facing particularly severe impacts due to resource limitations. The most affected by AMR is Healthcare Acquired Infections (HAIs), including Catheter-Related Bloodstream Infections (CRBSIs). These are commonly associated with biofilm-forming bacteria like Staphylococcus epidermidis, which complicates treatment due to antibiotic resistance. The Philippine variety of Psidium guajava, a folklorically used medicinal plant, has shown potential antimicrobial properties that could offer a new avenue for combating resistant pathogens.

METHODS

This study evaluated the antibacterial and antibiofilm efficacy of crude Psidium guajava ethanolic leaf extracts (PGELE) against biofilm-forming S. epidermidis (ATCC 12228). PGELE was tested at five concentrations (ranging from 312.5 µg/mL to 10,000 µg/mL) using two-fold serial dilution to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) using agar dilution count method. For the Minimum Biofilm Inhibitory Concentration (MBIC) and Minimum Biofilm Eradication Concentration (MBEC), crude PGELE was tested at 0.25 x MIC, 0.5 x MIC, MIC, 2 x MIC and 4 x MIC.

RESULTS

The MIC for PGELE against S. epidermidis was determined to be 2500 µg/mL, and the MBC was 5000 µg/mL, indicating that PGELE exhibits bactericidal activity. In biofilm assays, PGELE demonstrated strong antibiofilm activity at concentrations as low as 625 µg/ mL, inhibiting biofilm formation by more than 50%. However, PGELE did not eradicate preformed biofilms, as indicated by the MBEC results at concentrations ranging from 625 µg/mL to 10,000 µg/mL.

CONCLUSION

Psidium guajava ethanolic leaf extracts exhibit antibacterial and antibiofilm activities against S. epidermidis, particularly in preventing biofilm formation. These findings suggest that PGELE could be developed as an effective natural antimicrobial agent for use in healthcare settings to prevent CRBSIs and other infections caused by biofilm-forming pathogens. Further research and development are warranted to explore the potential of PGELE for antimicrobial drug development.

Plants ; Bacteria ; Staphylococcus Epidermidis ; Catheter-related Infections ; Psidium Guajava ; Psidium