Exploring the multifaceted pharmaceutical and medicinal applications of Cashew nut shell liquid (CNSL): Antimicrobial, anti-inflammatory and drug delivery potential

Cashew Nut Shell Liquid (CNSL) is a renewable phenolic lipid mixture obtained from the cashew nut pericarp and composed primarily of anacardic acids, cardanols, and cardols. These constituents have attracted interest due to reported antimicrobial, anti-inflammatory, antioxidant, and drug-delivery properties; however, published evidence remains largely descriptive, heterogeneous, and predominantly preclinical. The present review aims to provide a critical, quantitative evaluation of the pharmaceutical potential of CNSL by distinguishing natural and synthetic CNSL chemotypes, benchmarking bioactivity against standard drugs, reconciling safety with dose-dependent toxicity, and assessing translational and standardisation barriers. A structured literature search was conducted across PubMed, Scopus, Web of Science, and Google Scholar (2000 - 2025) using predefined keywords and inclusion criteria. Eligible studies were analysed for experimental model, concentration, comparator, and quantitative outcomes (MIC, IC50, selectivity index, toxicity metrics). Reported antimicrobial activities of anacardic acid show MIC values typically in the range of 8-128 µg/mL against Gram-positive bacteria, compared with <2 µg/mL for standard antibiotics, indicating moderate potency. Anti-inflammatory effects occur at micromolar IC50 levels but often overlap with cytotoxic concentrations, suggesting a narrow therapeutic window. Considerable variability in extract composition and the absence of standardized formulations limit reproducibility. No completed human clinical trials were identified. CNSL should be regarded not as an established therapeutic alternative but as a promising bioactive scaffold for formulation and medicinal chemistry optimization. This review provides methodological transparency, quantitative benchmarking, and critical appraisal to guide rational development of CNSL-based pharmaceutical systems.