RECENT STRATEGIES FOR IMPROVING SOLUBILITY AND ORAL BIOAVAILABILITY OF PIPERINE

Piperine, the main bioactive compound found in black pepper (Piper nigrum L.), has long been used in Ayurveda and traditional Chinese medicine (TCM). This compound has remarkable potential pharmacological properties, including being anti-inflammatory, antimicrobial, anticancer, anticonvulsant, antidepressant, neuroprotective, and hepatoprotective. Recent studies have reported piperine activity as an antiviral against SARS-CoV-2, which caused COVID-19. Nevertheless, the clinical use of piperine is still limited, due to its poor water solubility and bioavailability; therefore, various approaches have been developed in order to solve these limitations. This review summarises recent studies (i.e. uploaded to electronic databases in the last 10 y) regarding strategies that have been investigated to improve piperine’s solubility and pharmacokinetic properties, using ‘piperine’, ‘solubility’, ‘bioavailability’, and ‘formulation’ as keywords. Articles that have focused on piperine as the main compound were selected and sorted based on their modification and formulation types. Studies reported various approaches: from derivatives and analogue synthesis, crystal engineering, complexation, particle size reduction (micro-and nanonisation), and lipid-and polymer-based drug delivery systems, to inorganic and hybrid nanoparticles. This review also highlights limitations and challenges for these approaches and encourages further studies to optimise piperine’s potential benefits.