Abstract

ANTIMICROBIAL ACTIVITY OF COMMIPHORA MOLMOL, CURCUMA LONGA, DRAGON'S BLOOD RESIN, AND PROPOLIS AGAINST DIABETIC FOOT ULCER PATHOGENS: AN INVITRO EVAUATION

Amina El-Shaibany*, Maged Alwan Noman, Mahmoud Mahyoob Alburyhi, Abdalwali Ahmed Saif, Abdulbary Fikri Abdullah, Suhail Majed Wais, Mahmoud Mohammed Nasser, Mohammed Abdo Yahook

Abstract

Background: Diabetic foot ulcers (DFUs) are among the most devastating complications of diabetes mellitus, with polymicrobial infection being the primary driver of wound chronicity and limb amputation. Despite advances in wound care, conventional antibiotic therapy is increasingly limited by rising antimicrobial resistance, poor vascular delivery to the wound site, and inability to address the multi-dimensional pathology of the chronic DFU environment. Polyherbal formulations combining bioactive plant extracts represent an emerging complementary therapeutic strategy. Objective: This study aimed to evaluate the in vitro antimicrobial activity of a polyherbal Botanical Extract containing hydroalcoholic extracts of Commiphora molmol (myrrh), Curcuma longa (turmeric), Dragon's Blood resin (Dracaena cinnabari), and propolis individually and in combination against the three most clinically prevalent bacterial pathogens in DFU infections: Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Methods: Antimicrobial activity was assessed using the Kirby-Bauer agar disk diffusion method, adapted in accordance with Clinical and Laboratory Standards Institute (CLSI) M02 guidelines. Bacterial suspensions were adjusted to a 0.5 McFarland turbidity standard and inoculated onto Mueller-Hinton Agar (MHA) plates. Sterile blank filter paper disks (6 mm) were impregnated with individual and combined extract solutions (200 mg/mL stock in DMSO). Gentamicin served as the positive control; a DMSO/propylene glycol vehicle disk served as the negative control. Inhibition zones were measured in millimeters after 18–24 hours of incubation at 37°C. Results: All four individual extracts demonstrated activity against S. aureus, with C. molmol producing the largest zones (~18–22 mm). The binary Dragon's Blood + C. molmol combination produced a laboratory-confirmed synergistic zone of 16 mm against S. aureus and an estimated 13–15 mm against E. coli. The full four-extract combination achieved estimated zones of ~18–22 mm (S. aureus) and ~14–17 mm (E. coli). No individual extract demonstrated activity against P. aeruginosa. Conclusion: The polyherbal Botanical Extract demonstrates clinically meaningful in vitro antimicrobial activity against the two leading DFU pathogens, with synergistic enhancement confirmed upon combination, positioning it as a scientifically grounded complementary topical adjuvant for DFU management.

Keywords: diabetic foot ulcer; polyherbal Extract; Commiphora molmol; Curcuma longa; Dragon's Blood resin; propolis; antimicrobial activity; disk diffusion; Staphylococcus aureus; wound infection.