In vitro antimicrobial activity of Panchavalkala, an ayurvedic herbal formula: preliminary study

Abstract

Panchavalkala is a water extract of a combination of barks of five medicinal plants, widely used to treat wounds in Ayurvedic medicine. Three different combinations are commonly used as Panchavalkala in Sri Lanka. This study evaluated the in vitro antimicrobial activity (AMA) of three different combinations of Panchavalkala against common pathogens: Escherichia coli, Pseudomonas auregenosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. The combinations of Panchavalkala were prepared using pure raw materials according to the ayurvedic formulae. They were named A, B, and C and 60 g of total weight was used for water extraction and concentrated into 8:1 by boiling from each combination. Screening of AMA for each sample was carried out using the agar well diffusion assay in quadruplicate. Zones of inhibition of samples A, B, C against S. aureus and MRSA were 4.81 ± 0.26 mm, 4.69 ± 0.26 mm, 4.25 ± 0.27 mm, 3.88 ± 0.23 mm, 5.12 ± 0.23 mm, 4.50 ± 0.38 mm, respectively. Growth of S. aureus was significantly inhibited by sample C compared to amoxicillin used as a positive control (p = 0.01). Samples A and C showed a significant effect against MRSA compared to vancomycin (p = 0.01). None of the above combinations of Panchavalkala had an inhibitory effect on E. coli, P. auregenosa and C. albicans. All three combinations were effective against S. aureus, including MRSA in vitro. Further studies are recommended to explore the AMA of Panchavalkala used in Sri Lanka.