A pilot study on the antimicrobial efficacy of Coleus Aromaticus on Lactobacillus acidophilus – Comparative In-Vitro analysis of five samples on a single plate

Abstract

Objectives: Coleus aromaticus, also known as Indian borage, is a plant recognized for its medicinal uses, including potential antimicrobial properties. Lactobacillus acidophilus, a bacterium commonly found in the oral cavity and gastrointestinal tract, plays a crucial role in maintaining microbial balance but can lead to dental caries if imbalanced. The aim of this study is to assess the in vitro antimicrobial efficacy of C. aromaticus against L. acidophilus. Material and Methods: The study was performed by the utilization of homeopathic ethanolic and dry leaf extracts of C. aromaticus on Lactobacillus bacteria, with a control group treated with 0.2% chlorhexidine. For the preparation of the C. aromaticus extract, leaves were cleaned, dried, and ground into a paste. A 20 g portion of this paste was then weighed and used for extraction. In the assessment of inhibitory effects, the disc diffusion method was employed, and nutrient agar served as the growth medium. Discs loaded with the respective extracts were positioned on the agar, and the Petri dishes were subsequently incubated at 37°C for 24 h. Following the incubation period, the inhibitory zones surrounding the discs were measured using a measuring scale. Results: The study’s findings were determined by measuring the diameter of inhibition zones and assessing the mean values. It was observed that the aqueous extract derived from dried C. aromaticus leaves possesses antimicrobial activity against Lactobacillus. Specifically, it exhibited inhibition zones with diameters of 24 mm and 27 mm when using 100 µL/disc and 200 µL/disc, respectively. In comparison, the control group (0.2% chlorhexidine) displayed an inhibitory zone with a 23 mm diameter. Conclusion: The reason for these findings could be attributed to the existence of phytochemicals and essential volatile oils within C. aromaticus, which possess antimicrobial properties against Lactobacillus. This natural component appears to be effective in reducing Lactobacillus growth when used as an oral rinse containing phytochemicals.