5 years ago

Effect of neem (Azadirachta indica A. Juss) leaf extract on resistant Staphylococcus aureus biofilm formation and Schistosoma mansoni worms

Effect of neem (Azadirachta indica A. Juss) leaf extract on resistant Staphylococcus aureus biofilm formation and Schistosoma mansoni worms
There are ethnopharmacological reports supporting the use of neem (Azadirachta indica A. Juss) leaf against bacterial and worm infections. However there is a lack of studies about its effect on bacterial biofilm formation and Schistosoma mansoni worms. This study reports the in vitro effects of neem leaf ethanolic extract (Neem EE) on Methicillin-resistant Staphylococcus aureus (MRSA) biofilm and planktonic aggregation formation, and against S. mansoni worms. Materials and methods Quantification of the Azadirachtin (AZA), thought to be one of their main compounds related to biological effects, was performed. The effect of sub-inhibitory concentrations of Neem EE on biofilm formation and planktonic aggregates of S. aureus was tested using the crystal violet dye method and atomic force microscopy (AFM) analysis, respectively. Changes in S. mansoni motor activity and death of worms were analyzed in vitro after exposition to the extract. Treated schistosomes were also examined using confocal laser scanning microscopy. Results It was observed the presence of AZA in the extract (0.14±0.02mg/L). Testing Neem EE sub-inhibitory concentrations, a significant biofilm adherence inhibition from 62.5µg/mL for a sensitive S. aureus and 125µg/mL for two MRSA strains was observed. AFM images revealed that as the Neem EE concentration increases (from 250 to 1000µg/mL) decreased ability of a chosen MRSA strain to form large aggregates. In relation of anti-schistosoma assay, the extract caused 100% mortality of female worms at a concentration of 50µg/mL at 72h of incubation, while 300µg/mL at 24h of incubation was required to achieve 100% mortality of male worms. The extract also caused significant motor activity reduction in S. mansoni. For instance, at 96h of incubation with 100µg/mL, 80% of the worms presented significant motor activity reduction. By the confocal microscopy analysis, the dorsal surface of the tegument of worms exposed to 300µg/mL (male) and 100µg/mL (female) of the extract showed severe morphological changes after 24h of treatment. Conclusions Neem leaf ethanolic extract presented inhibitory effect on MRSA biofilm and planktonic aggregation formation, and anthelmintic activity against S. mansoni worms.

Publisher URL: www.sciencedirect.com/science

DOI: S0378874115301513

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.