Klebsiella pneumoniae Planktonic and Biofilm Reduction by Different Plant Extracts: In Vitro Study

Abstract

This study evaluated the action of Pfaffia paniculata K., Juglans regia L., and Rosmarius officinalis L. extracts against planktonic form and biofilm of Klebsiella pneumoniae (ATCC 4352). Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) values were determined for each extract by microdilution broth method, according to Clinical and Laboratory Standards Institute. Next, antimicrobial activity of the extracts on biofilm was analyzed. For this, standardized suspension at 107 UFC/mL of K. pneumoniae was distributed into 96-well microplates (n = 10) and after 48 h at 37°C and biofilm was subjected to treatment for 5 min with the extracts at a concentration of 200 mg/mL. ANOVA and Tukey tests (5%) were used to verify statistical significant reduction (p < 0.05) of planktonic form and biofilm. P paniculata K., R. officinalis L., and J. regia L. showed reductions in biomass of 55.6, 58.1, and 18.65% and cell viability reduction of 72.4, 65.1, and 31.5%, respectively. The reduction obtained with P. paniculata and R. officinalis extracts was similar to the reduction obtained with chlorhexidine digluconate 2%. In conclusion, all extracts have microbicidal action on the planktonic form but only P. paniculata K. and R. officinalis L. were effective against biofilm.

Anti-Biofilm Activity of Lactic Acid Bacteria Isolated from Kefir Against Multidrug-Resistant Klebsiella pneumoniae

“…The antibacterial activity of LAB CFS on K. pneumoniae was determined using the MTT assay 13 . Briefly, 5µL MTT solution (Cell Quanti-MTT TM Cell Viability Assay Kit) was added to each well followed by 1 h incubation at 37°C away from light.…”

As propriedades antimicrobianas do extrato glicólico de Casearia sylvestris Sw. em biofilme monotípico de cepas de Candida albicans e Candida glabrata

“…Embora o teste MTT seja amplamente utilizado para avaliar as interações de vários compostos químicos em biofilmes (Santos et al, 2020;de Oliveira et al, 2017;Paula-Ramos et al, 2016;de Oliveira et al, 2013) , as buscas realizadas nas bases de dados utilizadas neste trabalho (sendo as principais PubMed, Scielo e ScienceDirect) demonstram que ainda é necessário que mais estudos incorporem esta metodologia, por ser de fácil manuseio, relativamente mais barata quando comparada à técnicas como microscopia confocal e outras que visam visualizar o biofilme formado.…”

Algal polysaccharide’s potential to combat respiratory infections caused by Klebsiella pneumoniae and Serratia marcescens biofilms

“…In these environments, it is extremely hard to eradicate [8]. It is responsible for more than 70% of infections in humans and, more worryingly, is rapidly developing resistance to multiple antibiotics [9]. One big reason for their ability to survive is attributable to biofilms which assist K. pneumoniae resist harsh host environment inside chronically infected patients.…”

“…One big reason for their ability to survive is attributable to biofilms which assist K. pneumoniae resist harsh host environment inside chronically infected patients. Due to the combined threat of multiple virulence factors such as capsular polysaccharides, lipopolysaccharides, urease, outer membrane protein, and adherence factors, K. pneumoniae has acquired superbug status and is one of the most common antibiotic-resistant bacteria [9].…”

“…Bacterial biofilms are major contributors in causing RTIs [6]. Biofilm is an organised structure caused by groups of microorganisms which are encapsulated and protected by extra cellular matrix (ECM) which offers them great resistance to antimicrobial drugs [9]. The ECM layer comprises of DNA, proteins and polysaccharides [6].…”