Comparative evaluation of the antifungal efficacy of six different plant extracts and their synergistic effect against Candida albicans: An in vitro study

Abstract

Background: Chewing of sticks was a method of cleaning teeth in ancient India and is still followed by many people in the rural parts. People of different religions also hold high value for these plants that are of high medicinal value and have antimicrobial effects. Objectives: We previously in a study tried to evaluate the antibacterial efficacy of plant extracts from neem, miswak, liquorice, babul, pine, and black cumin against Lactobacillus acidophilus and Streptococcus mutans and have seen few positive results. In this study, we aim to use these extracts to determine if they show antifungal efficacy. Materials and Methods: Chewing sticks of neem, babul, miswak, liquorice, and the leaves of pine and seeds of black cumin were collected from plants sources and sun-dried after which they were ground into coarse powder. Sterile aqueous solutions of 5%, 10%, and 20% were prepared. Aqueous extraction and cold infusion were two methodologies we used. The filtrate was inoculated onto Sabouraud dextrose agar plate with chloramphenicol containing Candida and incubated at 37°C for 48 h. Results: Pine and black cumin showed good antifungal efficacy, on increasing the concentration the extracts of miswak and liquorice also showed a better antifungal efficacy. The combination of these plant extracts had better efficacy than individual extracts of babul and pine. The extracts obtained from cold infusion method almost showed equal antifungal efficacy in comparison to the standard chlorhexidine used. Conclusion: These plants extracts previously having showed antibacterial efficacy and good antifungal effects can be considered for preparations of commercial antiplaque agents.