It is not unusual for naturally occurring compounds to be limited for their use in cosmetics due to their low water solubility. Recently, aiming at accessing novel phlorizin analogues, we reported the synthesis of very promising - but low water-soluble - biomass-derived chalcones (CHs) and dihydrochalcones (DHCs) exhibiting antioxidant and anti-tyrosinase activities. Glycosylating bioactive compounds being one of the most common strategies to increase water solubility, herein we report the enzymatic glycosylation of the aforementioned CHs, as well as DHC, using cyclodextrin glycosyltransferases (CGTase), enzymes well-known for catalyzing the selective ⍺(1→4)transglycosylation. Indeed,while most natural glycosides areβ-glycosides (such as phlorizin), the selected enzyme produces selectively newα-glycosides, thus expanding their structural diversity. A first separation using Centrifugal Partition Chromatography (CPC) led to mono-, di- or triglycosides-enriched fractions, which were then submitted to a comprehensive purification strategy for an in-depth chemical profiling of the synthesizedα-glycosides, revealingas major compounds. Surprisingly, among the diglycosides characterized, besides the expected maltoside compounds, nigeroside derivatives were also identified in significant amounts, depending on the starting compound structure. Finally, evaluating the antiradical, anti-tyrosinase and antimicrobial activities of the major glycosides revealed them as potential sustainable alternatives to current petro-sourced cosmetic ingredients.
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