Synthesis and Biological Evaluation of Glucosyl Curcuminoids

Abstract

Medicinal plants proved to be a rich source in exploring a variety of lead structures in the development of new drugs. The natural curcuminoids have gained considerable attention in recent years for their multiple beneficial pharmacological and biological activities. Clinical application of these curcuminoids is often impaired due to their poor water solubility, resulting in low in vivo bioavailability of the active compound in humans. The objective of the present study is to synthesize glucosyl conjugates of curcumin 1 and tetrahydrocurcumin 4 and to evaluate their biological activities. The study highlights the synthesis of curcumin-β-di-glucoside 3 (yield 71%) and tetrahydrocurcumin-β-di-glucoside 6 (yield 64%) in good yields in a biphasic reaction medium using a phase transfer catalyst under simple and ecofriendly conditions. Both the glucosyl curcuminoids showed enhanced antioxidant, tyrosinase enzyme inhibitory, antimicrobial and potent cytotoxic activity. The improved biological activity may be due to the increased solubility of the glucosyl conjugated compounds compared to the native curcuminoids; this was further confirmed by partition coefficient studies. Thus, the synthesized glucosyl curcumin may serve as promising future therapeutic molecule in the management of cancer, whereas glucosyl tetrahydrocurcumin can be a useful ingredient in achromatic food and in cosmetic applications.

The Homoleptic Curcumin–Copper Single Crystal (ML2): A Long Awaited Breakthrough in the Field of Curcumin Metal Complexes

“…The log p value of curcumin is 3.1 ± 0.04, consistent with previous reports [ 70 , 71 ], while the log p of complex 1 was 2.3 ± 0.15, indicating that the latter has better water solubility and therefore better bioavailability.…”

The effect of curcumin on healing in an animal nasal septal perforation model

“…In our study, although there was no statistical difference between the groups in terms of fibroblast and angiogenesis processes, the amount of granulation tissue was significantly higher in the curcumin group. This can be explained by the effects of curcumin on the proliferative phase in wound healing . In addition, the high level of cartilage regeneration in the curcumin group indicates a faster recovery.…”

Natural antioxidants–properties and possible applications

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