Bioactivity of Lunas Bagon (Piper sp.) and Himag (Lunasia sp.) against Staphylococcal Strains

Abstract

INTRODUCTION

Antibiotic resistance has become a global crisis as multiple antibiotics have lost potency to major bacterial strains. Apparently, there is a pressing need of sourcing out novel compounds for antibiotic development. This study aimed to investigate the antibacterial activity of plants used in folkloric medicine in Surigao del Sur---Lunas Bagon (Piper sp.) and Himag (Lunasia sp.).

METHODS

Ethanolic stem extracts of Lunas Bagon and Himag were subjected to phytochemical screening and antibacterial testing against Staphylococcus aureus BIOTECH 1582 and Methicillin-Resistant S. aureus (MRSA). Filter Paper Disc Diffusion Assay was also conducted. For each strains, there were four treatments—Lunas Bagon extract, Himag extract, positive control(commercial antibiotic), and negative control (distilled water). Each treatment was done in three replicates and trials. The zones of inhibition (ZOI) were measured after 24 hours of incubation.

RESULTS

For S. aureus, the following ZOI were recorded: Lunas Bagon (12.44 mm, partially active), Himag (13.56 mm, partially active), Penicillin G (32.00 mm, very active), and distilled water (6.00 mm, inactive). The following ZOI were observed for MRSA: Lunas Bagon (6.00, inactive), Himag (14.22 mm, partially active), Vancomycin (23.67 mm, active), and distilled water (6.00 mm, inactive). ANOVA and Post Hoc test revealed that Lunas Bagon and Himag have similar potency against S. aureus; they have higher ZOI than the negative control but the positive control still is the most potent substance among all treatments. For MRSA, ANOVA revealed that different treatments have different potency and Post Hoc test showed that Himag is more potent than Lunas Bagon and distilled water but it showed lesser potency to MRSA when compared to vancomycin. The bioactivity exhibited by Lunas Bagon and Himag could be attributed to the phytochemicals present in them. Lunas Bagon were found to contain alkaloids and saponins while Himag contained flavonoids, saponins and tannins.

DISCUSSIONS

The results demonstrated that both plants exhibited bioactivity to S. aureus BIOTECH 1582; but only Himag showed bioactivity against a more resistant strain—MRSA. When compared to penicillin and vancomycin, the plants showed lesser potency to the bacterial strains. Nevertheless, the plants, particularly Himag, showed potential of becoming a novel source of antibiotic for drug-resistant bacteria; hence, the need of isolation and specific identification of the plant's bioactive compounds.