Comparative Antimicrobial Activities of Neem and Curry Leaf Extracts and Their Synergistic Effect Against Selected Pathogenic Bacteria and Fungus

Abstract

There is a growing demand today for naturally derived drugs and medicine in place of synthetic drugs that are more commercially available. Such drugs derived from indigenous plants are effective as they contain potent therapeutically active compounds of the plants that show antimicrobial activity against a variety of pathogens that cause common diseases. Such diseases as periodontitis and oral candidiasis are a growing concern these days. This study was undertaken to investigate the antimicrobial activity of two indigenous Indian plants, Azadirachta indica and Murraya koenigii and their synergistic effect, if any, against three pathogenic microorganisms associated with oral diseases and one pathogenic bacteria known to be a nosocomial causative agent. Three bacterial species (Streptococcus mutans, Streptococcus gordonii, Pseudomonas aeruginosa) and one fungal species (Candida albicans) were selected for antimicrobial assays. Both ethanolic and methanolic extracts were prepared from the leaves of the two plant species in addition to an aqueous extract of A. indica and an n-hexane extract of M. koenigii. Antibacterial and antifungal assay was done using agar well diffusion method under standard culture conditions. Inhibitory activity was observed for all extracts against P. aeruginosa while A. indica and M. koenigii showed ineffectiveness in inhibiting growth of C. albicans and S. mutans respectively. C. albicans and S. mutans were selected for study of synergistic effect based on the results of the initial assay, however there was no synergistic activity observed for any combination of extract mixtures.

Synergism effect of Murraya koneigii and Piper betle leaves extracts on antibacterial activity against Gram Positive bacteria

“…This finding is parallel to what Bhuva [3] found where it is better for the individual leaves of M. koenigii and Azadirachta indica (neem leaves) to be used separately for an enhanced antibacterial activity against the bacteria strain such Streptococcus mutans, Streptococcus gordonii, and Pseudomonas aeruginosa. Likewise, it is found that M. koenigii is being slightly selective with respect to the use of leaves it is combined with, against gram-positive bacteria, like in the work conducted by Subramaniam [19].…”

Antibacterial and antifungal activities of essential oils from medicinal plants found in the South Pacific

“…The weak antifungal properties of these essential oils are in agreement with those reported in literature such as, C. odorata (Kuspradini et al, 2016;Lee and Lee, 2010), E. hortensis (Huish et al, 2014;Yazdanpanah and Mohamadi, 2014), M. koenigii (Bhuva and Dixit, 2015;Kumar et al, 2010). The weak antifungal activity of essential oils in this study can be due to the absence of strong antifungal compounds that include linalool, eugenol and other phenolic compounds as reported in different plant extracts (Campaniello et al, 2010;Tan et al, 2015).…”

Evaluation of antimicrobial activity of leaf extract of Gymnema sylvestre

“…As compared with synthetic drugs, naturally derived drugs are therapeutically active and commercially available [15] . The antimicrobial activity and MIC ranges between 10.00 mg/ml to 100 mg/ml exhibited by aq.…”