An updated review of tyrosinase inhibitors is presented, focusing on natural and synthetic compounds that inhibit tyrosinase, an enzyme involved in melanogenesis and enzymatic browning. Tyrosinase is a copper-containing oxidase that catalyzes the first two steps of melanin synthesis and is responsible for browning in fruits and fungi. Hyperpigmentation in human skin and browning in fruits are undesirable, prompting research into effective tyrosinase inhibitors for use in cosmetics and food preservation. The review discusses the biochemical characteristics and reaction mechanisms of tyrosinase, including its three forms (oxy-, met-, and deoxytyrosinase) and their roles in melanin formation. Tyrosinase inhibitors are classified into six categories, with only specific inactivators and inhibitors considered "true inhibitors" as they directly interact with the enzyme. Inhibitors are evaluated based on their inhibitory strength, measured by IC50 values, and compared to kojic acid, a standard inhibitor. Natural and synthetic tyrosinase inhibitors are categorized into five major classes: polyphenols, benzaldehyde and benzoate derivatives, long-chain lipids and steroids, other natural or synthetic inhibitors, and irreversible inactivators. Polyphenols, such as flavonoids, are the most studied inhibitors, with various subclasses like flavonols, flavones, and isoflavonoids showing different inhibitory activities. Flavonoids with specific hydroxyl groups, such as 3-hydroxy-4-keto moieties, exhibit strong inhibitory effects by chelating copper. Benzaldehyde and benzoate derivatives, including compounds like aloesin and esculetin, are also effective tyrosinase inhibitors. Stilbenes, such as oxyresveratrol and piceatannol, show potent inhibitory activity, with piceatannol exhibiting both direct enzyme inhibition and quinone scavenging effects. Coumarins, like aloesin, are natural inhibitors with multifunctional properties. Synthetic derivatives, such as HNB, demonstrate exceptional inhibitory activity, with HNB being the strongest tyrosinase inhibitor reported to date. The review highlights the importance of structural features, such as the 4-resorcinol and 5-resorcinol moieties, in determining inhibitory potency. The inhibitory mechanisms vary, including competitive, non-competitive, and suicide inhibition. The study emphasizes the need for further research to understand the structural-activity relationships and to develop more effective tyrosinase inhibitors for applications in cosmetics and food preservation.An updated review of tyrosinase inhibitors is presented, focusing on natural and synthetic compounds that inhibit tyrosinase, an enzyme involved in melanogenesis and enzymatic browning. Tyrosinase is a copper-containing oxidase that catalyzes the first two steps of melanin synthesis and is responsible for browning in fruits and fungi. Hyperpigmentation in human skin and browning in fruits are undesirable, prompting research into effective tyrosinase inhibitors for use in cosmetics and food preservation. The review discusses the biochemical characteristics and reaction mechanisms of tyrosinase, including its three forms (oxy-, met-, and deoxytyrosinase) and their roles in melanin formation. Tyrosinase inhibitors are classified into six categories, with only specific inactivators and inhibitors considered "true inhibitors" as they directly interact with the enzyme. Inhibitors are evaluated based on their inhibitory strength, measured by IC50 values, and compared to kojic acid, a standard inhibitor. Natural and synthetic tyrosinase inhibitors are categorized into five major classes: polyphenols, benzaldehyde and benzoate derivatives, long-chain lipids and steroids, other natural or synthetic inhibitors, and irreversible inactivators. Polyphenols, such as flavonoids, are the most studied inhibitors, with various subclasses like flavonols, flavones, and isoflavonoids showing different inhibitory activities. Flavonoids with specific hydroxyl groups, such as 3-hydroxy-4-keto moieties, exhibit strong inhibitory effects by chelating copper. Benzaldehyde and benzoate derivatives, including compounds like aloesin and esculetin, are also effective tyrosinase inhibitors. Stilbenes, such as oxyresveratrol and piceatannol, show potent inhibitory activity, with piceatannol exhibiting both direct enzyme inhibition and quinone scavenging effects. Coumarins, like aloesin, are natural inhibitors with multifunctional properties. Synthetic derivatives, such as HNB, demonstrate exceptional inhibitory activity, with HNB being the strongest tyrosinase inhibitor reported to date. The review highlights the importance of structural features, such as the 4-resorcinol and 5-resorcinol moieties, in determining inhibitory potency. The inhibitory mechanisms vary, including competitive, non-competitive, and suicide inhibition. The study emphasizes the need for further research to understand the structural-activity relationships and to develop more effective tyrosinase inhibitors for applications in cosmetics and food preservation.