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

Background and Objective: Staphylococcus aureus is the leading cause of skin and soft tissue infections such as abscesses, furuncles, and cellulitis. Biofilm forming strains of S. aureus have higher incidence of antimicrobial resistance to at least three or more antibiotics and are considered as multidrug resistant. Since S. aureus biofilm-producing strains have higher rates of multidrug and methicillin resistance compared to non-biofilm-producing strains, the need for alternative therapeutic option is important. Furthermore, rates of methicillin-resistant Staphylococcus aureus (MRSA) in Asia remain high. Results of the study may provide support for the clinical uses of P. betle as a topical antibacterial and antiseptic in the treatment and prevention of infections involving the skin, mouth, throat, and indwelling medical devices. Thus, this study aimed to evaluate the in vitro antibacterial and antibiofilm activities of Piper betle L. ethanolic leaf extract (PBE) against a biofilm-forming methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA). Methods: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of PBE against MSSA were determined using the agar dilution assay. The biofilm inhibition and eradication assays using crystal violet were done to quantify the antibiofilm activities of PBE on MSSA biofilm. Results: PBE showed activity against MSSA in agar dilution assay with MIC and MBC values of 2500 μg/mL and 5000 μg/mL, respectively. At subinhibitory concentrations, PBE showed biofilm inhibition activity at 1250 μg/mL but a lower percent eradication of biofilms as compared to oxacillin was noted. Conclusion PBE showed antibacterial activities including biofilm inhibition against methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA).
Piper betle ; Staphylococcus aureus ; Anti-Bacterial Agents ; Biofilms

Background and Objective: Staphylococcus aureus is the leading cause of skin and soft tissue infections such as abscesses, furuncles, and cellulitis. Biofilm forming strains of S. aureus have higher incidence of antimicrobial resistance to at least three or more antibiotics and are considered as multidrug resistant. Since S. aureus biofilm-producing strains have higher rates of multidrug and methicillin resistance compared to non-biofilm-producing strains, the need for alternative therapeutic option is important. Furthermore, rates of methicillin-resistant Staphylococcus aureus (MRSA) in Asia remain high. Results of the study may provide support for the clinical uses of P. betle as a topical antibacterial and antiseptic in the treatment and prevention of infections involving the skin, mouth, throat, and indwelling medical devices. Thus, this study aimed to evaluate the in vitro antibacterial and antibiofilm activities of Piper betle L. ethanolic leaf extract (PBE) against a biofilm-forming methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA). Methods: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of PBE against MSSA were determined using the agar dilution assay. The biofilm inhibition and eradication assays using crystal violet were done to quantify the antibiofilm activities of PBE on MSSA biofilm. Results: PBE showed activity against MSSA in agar dilution assay with MIC and MBC values of 2500 μg/mL and 5000 μg/mL, respectively. At subinhibitory concentrations, PBE showed biofilm inhibition activity at 1250 μg/mL but a lower percent eradication of biofilms as compared to oxacillin was noted. Conclusion PBE showed antibacterial activities including biofilm inhibition against methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA).
Piper betle ; Staphylococcus aureus ; Anti-Bacterial Agents ; Biofilms

Background: A rise in the number of immunocompromised patients has increased the risk of opportunistic fungal infections. Identifying novel sources of antifungal agents from commonly discarded materials (i.e. potato peelings) can provide a cheaper alternative for antifungal drugs.

Objectives: The aim of the study was to determine the antifungal activity of crude glycoalkaloid extract from Solanum tuberosum L. (white potato) peelings against opportunistic fungi Candida albicans, Candida glabrata, Aspergillus niger, Aspergillus fumigatus, and Aspergillus flavus.

Methods: The glycoalkaloid content from dried potato peelings were extracted using ethanol and confirmed using colorimetric tests.The extract had a concentration 833.33 microgram/mL. Determination of the minimum inhibitory concentrations (MICs) of the extract via two-fold broth dilution was performed for the five fungi with amphotericin B and fluconazole as the reference antifungal drugs.

Results: MICs of the crude extract for C. albicans, C. glabrata, A. fumigatus, and A. niger were not found within the concentration range of the studies and would thus need further experiments using a broader range of glycoalkaloid concentrations. The extract was found to have a MIC of 104.17microgram/mL for A. flavus, thereby verifying the antifungal effect of glycoalkaloid against A. flavus at said concentration.

Conclusion: Glycoalkaloids from Solanum tuberosum are a potential source of antifungals against certain opportunistic fungi.

Plant ; Solanum Tuberosum ; Aspergillus ; Candida