Exploring the disinfectant potential of plant extracts against bacterial strains

Abstract

The massive and excessive use of disinfectants has harmful effects on ecosystems and human health. This study aimed to evaluate the potential effect of the methanol extracts of Peganum harmala, Pistacia lentiscus, Rubia tinctorum, and Nardostachys grandiflora. Antimicrobial activity was tested against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Pseudomonas aeruginosa ATCC 27853, the disinfectant potential was determined using the dilution-neutralization method (NF EN1040/T72-152, 2006). A phytochemical assay was carried out on plant extracts employing the Folin-Ciocalteu method for the quantification of polyphenols, and the aluminum chloride method (AlCl₃) was used to determine the flavonoid content. The results revealed the antimicrobial activity of Peganum harmala against all the strains, with a minimum inhibitory concentration (MIC) between 1 and 4 mg/mL, followed by Pistacia lentiscus and Rubia tinctorum, with MICs between 2 and 16 and 4 and 16 mg/ml, respectively. However, only Peganum harmala showed significant disinfectant activity, with microbial reduction ranging from 4.66 log₁₀ CFU/mL to 3.19 log₁₀ CFU/mL after 5 minutes of contact. The phytochemical assay revealed a flavonoid content of 79 ± 2.5 μg eq Que/mg E and a phenol content of 72 ± 0.88 μg eq AG/mg E in Peganum harmala. Peganum harmala has significant potential as a natural disinfectant. Further research should focus on the development of eco-friendly and cost-effective disinfection methods. This would help mitigate the negative impacts of chemical disinfectants on ecosystems and human health.