Antibiofilm potential of Psidium guajava and Passiflora edulis pulp extracts against Staphylococcus aureus, cytotoxicity, and interference on the activity of antimicrobial drugs

Abstract

Background Pathogenic strains of Staphylococcus aureus can cause several diseases including septicemia and endocarditis, in spite of being a commensal species of the human microbiota. The current drug resistance of S. aureus raises the need for new antimicrobials, and natural products represent a feasible source for prospection of such compounds, due to features including the diversity of structures and mechanisms of action. Here, we provide evidence of the antimicrobial activity of methanolic of Psidium guajava and Passiflora edulis pulps against planktonic cells and biofilms of clinical isolates of S. aureus. Results The extracts were effective against the strains in concentrations up to 7.81 and 250 μg/mL for planktonic cells and biofilms, respectively. Antagonistic interactions of the extracts to antimicrobial drugs were observed. The pulps caused no cytotoxic effects on BGM cells. GC-MS analysis found relevant molecules, and UPLC analysis suggested the presence of flavonoids. To the best of our knowledge, this is the first antibiofilm evidence of such extracts. Conclusion The extracts seem to be safe and effective enough for more studies aiming at exploring isolated antimicrobial molecules using in vivo models for the treatment of staphylococcal diseases.

Psidium guajava L.: From byproduct and use in traditional Mexican medicine to antimicrobial agent

“…The MBEC (Minimum Biofilm Eradication Concentration) reported by dos Santos et al ( 44 ) (250 μg/ml) is lower than those reported by Dutta et al ( 69 ) (1,000–2,100 μg/ml). This could indicate that probably the guava leaf extract has a higher activity compared to the compound Benzyl isocyanate (isolated from guava leaves) on its own.…”

“…Nonetheless, an aspect to consider during the use of industrial byproducts is the possible presence of food additives, as is the case of the pulp extract used by dos Santos et al ( 44 ), which contained different additives, among them, the antioxidant BHT, which may cause allergies, eczema, rash, and angioedema, therefore BHT cannot exceed an ADI of 0.5 mg/kg ( 48 ). As the presence of these additives probably remains after the extraction and can affect the activity of the extract, it is important to determine in what concentrations are they found in the plant material and what are the possible toxicological effects that they may cause depending on the route of administration.…”

“…It should be noted that a proper comparison between studies cannot be made, even if similar methodologies were used, since each author established the MIC differently, for example, Soliman et al ( 41 ) defined MIC as the lowest concentration that had granular appearing micro-colonies of growth instead of filamentous radiating colonies on solid agar; while for Hemeg et al ( 68 ) MIC was the lowest concentration of extract that resulted in no visible growth on the surface of the agar. In addition, we can also find multiple differences between the methods to measure the antimicrobial effect, for example, dos Santos et al ( 44 ) used a 0.1% resazurin solution, while Festus et al ( 67 ) analyzed bacterial growth based on turbidity.…”

Production of highly cytotoxic and low immunogenic L-asparaginase from Stenotrophomonas maltophilia EMCC2297

“…HepG-2 and K-562 cells were grown in Rosewell Park Memorial institute medium (RPMI-1640) (Sigma Aldrich, USA) supplemented with 50 µg/ml gentamycin and 10% inactivated fetal calf serum. The cells were kept at 37ºC in a humidified atmosphere with 5% CO 2 and were sub-cultured two to three times a week (Cruz et al 2020 ; dos Santos et al 2020 ). On the other hand, MRC-5 cells were propagated in Dulbecco’s modified Eagle’s medium (DMEM) (Sigma Aldrich, USA) containing 10% heat-inactivated fetal bovine serum, HEPES buffer (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), 1% L-glutamine, and 50 µg/ml gentamycin.…”

In silico anti-quorum sensing activities of phytocompounds of Psidium guajava in Salmonella enterica serovar Typhi

“…There abounds, in the literature, evidence of anti-bacterial and anti-biofilm properties of plant materials that can be harnessed for combating antimicrobial resistance of pathogenic organisms by interrupting the biofilm formation system. For instance, various parts of P. guajava have been reported for anti-biofilm activities against Staphylococcus aureus (250 μg/mL of pulp extract) [12], Streptococcus mutans and Streptococcus gordonii (0.78 mg/mL of leave extract) [28]. Fu et al also reported that aqueous extract of Herba patriniae exhibited an inhibitory effect on almost all the studied biofilm-related genes of Pseudomonas aeruginosa with a significant reduction in the formation of biofilm as well as an alteration in the structure of the mature biofilms.…”