Antibacterial and Antibiofilm Activity of Methanolic Plant Extracts against Nosocomial Microorganisms

Abstract

Biofilm is a complex microbial community highly resistant to antimicrobials. The formation of biofilms in biotic and abiotic surfaces is associated with high rates of morbidity and mortality in hospitalized patients. New alternatives for controlling infections have been proposed focusing on the therapeutic properties of medicinal plants and their antimicrobial effects. In the present study the antimicrobial and antibiofilm activities of 8 methanolic plant extracts were evaluated against clinical isolated microorganisms. Preliminary screening by diffusion well assay showed the antimicrobial activity of Prosopis laevigata, Opuntia ficus-indica, and Gutierrezia microcephala. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined ranging from 0.7 to >15 mg/mL. The specific biofilm formation index (SBF) was evaluated before and after the addition of plant extracts (MBC × 0.75). Opuntia ficus-indica caused the major reduction on SBF in dose-dependent manner. Cytotoxic activity of plant extracts was determined using brine shrimp lethality test (Artemia salina L.). Lethal Dose concentration (LD50 values) of the plant extracts was calculated. LD50 values for P. laevigata and G. microcephala were 141.6 and 323.3 µg/mL, respectively, while O. ficus-indica showed a slight lethality with 939.2 µg/mL. Phytochemical analyses reveal the presence of flavonoids, tannins, and coumarines.

Phytochemical Screening by High Performance Liquid Chromatography (Hplc) and Antimicrobial Activity of Different Solvent Fractions of Areca Nuts Against Bacillus Subtilis Biofilm

“…subtilis has ability to form floating biofilm or pellicle at liquidair interface 18,31 which is in agreement with this study (Figure 1). Bacterial biofilm formation is an important topic since last decade 32 as it provides shelter to bacteria residing inside and helps bacteria to become resistant to drugs and antibiotics. Biofilms dwelling bacteria are considered 1000 times more resistant to antibiotics than free floating cells 31 .…”

“…Many factors are responsible for biofilm resistance like expression of multidrug efflux pumps, type IV secretion systems, restricted diffusion of antibiotics in biofilm matrix, decreased permeability, and action of antibiotic modifying enzymes 33 . An antibiofilm agent of plant origin is a hot topic these days as they are considered safe and have no side effects 32 . In this study, all three extracts inhibited the biofilm formation of B. subtilis ( Figure 4).…”

Phytopharmaceutical Potentials of Prosopis Laevigata, Symplocos Cochinchinensis and Nymphaea Alba: A Review

“…The plant extract of P. laevigata from the minimum bacterial concentration showed anti-biofilm activity with considerable reduction against specific biofilm formation of E.coli and S. aureus. Anti-biofilm properties are a result of phytochemical properties like antibacterial property [14]. However, the full potential of anti-biofilm activity in P.…”

Removal of the Bad Effects of D-Galactosamine on Blood Lipids of Male Wistar Rats By Black and Green Tea Consumption

“…Plants played a significant role in maintaining human health and improving the quality of human life for thousands of years, and have served humans well as valuable components of seasonings, cosmetics, dyes, medicines, and beverages (Sánchez et al, 2016). On a global level, tea is the most popular beverage and about 3 billion kilograms of tea are produced and consumed yearly (Yang and Landau, 2000).…”