Bioactive Compounds of the Indian Toad (Duttaphrynus melanostictus) and Their Emerging Pharmaceutical Applications: Mechanistic and Translational Perspectives

The Indian common toad (Duttaphrynus melanostictus) is a widely distributed amphibian species across South and Southeast Asia and represents a valuable source of biologically active secondary metabolites. Secretions from its parotoid glands and skin contain diverse pharmacologically important compounds, including bufadienolides, sterols, indole alkaloids, antimicrobial peptides, and biogenic amines. Accumulating experimental evidence demonstrates a broad spectrum of therapeutic activities such as anticancer, antidiabetic, antimicrobial, anti-inflammatory, cardiotonic, antioxidant, and drug-bioavailability enhancing effects. Mechanistically, these bioactive molecules act through modulation of Na⁺/K⁺-ATPase activity, induction of apoptosis via mitochondrial pathways, inhibition of angiogenesis, regulation of oxidative stress, and interaction with efflux transporters such as P-glycoprotein. This comprehensive review critically evaluates the taxonomy, phytochemical and biochemical composition, molecular pharmacology, preclinical evidence, toxicological considerations, pharmaceutical applications, and future translational prospects of bioactive compounds derived from Duttaphrynus melanostictus, highlighting its emerging significance in modern drug discovery research.