Microalgae and Macroalgae as Advanced Sources of Tyrosinase Inhibitors.

Area of Science:

• Biochemistry and Marine Biotechnology
• Enzymology and Natural Product Chemistry

Background:

• Tyrosinase (EC 1.14.18.1) is crucial for melanogenesis and food browning, creating demand for safe inhibitors.
• Conventional synthetic tyrosinase inhibitors exhibit cytotoxicity and stability issues.
• Marine natural products (MNPs) from algae offer a promising alternative source of effective inhibitors.

Purpose of the Study:

• To explore marine algae as a source of potent and safe tyrosinase inhibitors.
• To investigate the diverse structures and inhibitory mechanisms of algal compounds.
• To identify strategies for enhancing the stability and bioavailability of MNPs for applications.

Main Methods:

• Screening of macroalgae (e.g., brown seaweeds) and microalgae for tyrosinase inhibitory activity.
• Characterization of active compounds, including phlorotannins (e.g., dieckol) and microalgal metabolites (e.g., scytonemin monomer).
• Mechanistic studies using molecular docking to elucidate binding modes and inhibition kinetics.

Main Results:

• Dieckol from brown algae demonstrated non-competitive inhibition with an IC50 of 2.16 µg/mL.
• Scytonemin monomer from microalgae showed potent competitive inhibition (IC50 of 4.90 µM), surpassing kojic acid.
• Diverse binding mechanisms were observed, including slow binding and specific competitive interactions.

Conclusions:

• Marine algae are a rich source of structurally diverse and potent tyrosinase inhibitors.
• Green extraction techniques (e.g., NADESs) and advanced delivery systems (e.g., NLCs) are essential for translational success.
• MNPs hold significant potential for cosmeceutical and medical applications due to their safety and efficacy.