Asian Journal of Research in Botany

The growing resistance of microorganisms to conventional antimicrobial agents has intensified interest in medicinal plants as potential sources of bioactive compounds. This study investigated the in-vitro antifungal and antibacterial effects of Polyherbal Formulation IB-01, comprising six medicinal plants: Azadirachta indica, Rubia cordifolia, Phyllanthus emblica, Zingiber officinale, Curcuma longa, and Glycyrrhiza glabra. Ethanolic extracts were prepared by Soxhlet extraction, dried, and subsequently diluted in dimethyl sulfoxide and sterile distilled water. Antimicrobial activity was examined by agar well diffusion using 5, 10, 25, 50, and 100 µl against five fungal species—Aspergillus flavus, Mucor globosus, Fusarium oxysporum, Penicillium notatum, and Rhizopus microsporus—and three bacterial species—Bacillus cereus, Escherichia coli, and Staphylococcus aureus. All tested microorganisms displayed inhibition zones, which generally increased with the applied volume. At 100 µl, inhibition zones of 12 mm were recorded for both Aspergillus flavus and Mucor globosus, whereas Fusarium oxysporum, Penicillium notatum, and Rhizopus microsporus produced zones of 6, 8, and 7 mm, respectively. For the bacterial isolates, zones at 100 µl measured 8 mm for Bacillus cereus, 7 mm for Staphylococcus aureus, and 6 mm for Escherichia coli; control values ranged from 0 to 1 mm. Thus, IB-01 demonstrated measurable antimicrobial activity under the specified in vitro conditions. Nevertheless, inhibition-zone data alone cannot determine minimum inhibitory, fungicidal, or bactericidal concentrations, nor can they establish mechanism, synergy, or clinical efficacy. Replicated quantitative testing with appropriate reference controls is therefore required before comparative potency or therapeutic relevance can be determined.