Evaluation of Antimicrobial Efficacy of Crude Venom from the Indian Red Scorpion (Hottentotta tamulus) against Multidrug-Resistant Pathogens
Jay Prakash Singh
*
B.M.S. College of Pharmacy, Amethi-229309, UP, India.
Durga Prasad Patel
Sandipani College of Pharmacy, Pendri, Masturi, Bilaspur, Chhattisgarh, India.
Durgesh Ray
RGS College of Pharmacy, Lucknow, India.
Subhashish Tripathy
B.M.S. College of Pharmacy, Amethi-229309, UP, India.
Chetna Singh
Motherhood University, Uttarakhand, India.
Atul Kumar Singh
Shri Vishwanath College of Pharmacy, Kalan, Sultanpur, India.
Prashant Kumar
Sahu Onkar Sharan School of Pharmacy, Faculty of Pharmacy, IFTM University, Moradabad, Uttar Pradesh 244201, India.
KM. Dipika
B.M.S. College of Pharmacy, Amethi-229309, UP, India.
*Author to whom correspondence should be addressed.
Abstract
Antimicrobial resistance (AMR) is an escalating global health crisis, with multidrug-resistant (MDR) pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Acinetobacter baumannii undermining current treatment options. In this study, the crude venom of the Indian red scorpion (Hottentotta tamulus) was investigated for its antimicrobial potential (Ljungars & Laustsen, 2023). The venom, extracted and processed under controlled conditions, was evaluated against a panel of clinically relevant MDR pathogens, including MRSA, Pseudomonas aeruginosa, A. baumannii, Klebsiella pneumoniae, and Escherichia coli. Broth microdilution assays revealed minimum inhibitory concentration (MIC) values ranging from 8 to 64 µg/mL, with the strongest activity observed against MRSA (MIC = 8 µg/mL) and A. baumannii (MIC = 16 µg/mL). Minimum bactericidal concentration (MBC) values closely matched MICs, indicating a definitive bactericidal mode of action. Time-kill kinetics confirmed rapid bacterial clearance, achieving ≥3-log10 reductions in CFU/mL within 2 hours for MRSA and 4 hours for A. baumannii at 2× MIC, without regrowth up to 24 hours. Furthermore, checkerboard assays demonstrated a strong synergistic effect between the venom and ciprofloxacin (FICI = 0.25), significantly enhancing antibacterial efficacy (Ghodeif et al. 2025). These findings highlight the potential of H. tamulus venom as a promising source of novel antimicrobial peptides and a viable adjunct in combination therapies to combat MDR infections.
Keywords: Antimicrobial resistance, multidrug-resistant bacteria, Hottentotta tamulus, scorpion venom, antimicrobial peptides, MRSA, Acinetobacter baumannii