Enzymatic rutinosylation of phenolic compounds by 6-O-alfa-rhamnosyl-beta-glucosidase from Sarocladium strictum and evaluation of their antitumoral effects

GONZALEZ A; WEIZ G; MOLEJON, MI; BRECCIA JD

Graz

Congreso; BIOTRANS 2021; 2021

6-O-α-L-rhamnosyl-β-D-glucosidases are diglycosidases that catalyze the cleavage of the glycosidic bond between the aglycone and the disaccharide rutinose (α-L-rhamnopyranosyl-(1→6)-β-D- glucopyranose)[1]. Retaining α-L-rhamnosyl-β-D-glucosidases exhibit transglycosylation activities which provide an approach for obtaining novel rutinosylated molecules with enhanced capacities. These rutinosides could exhibit novel biological and biomedical activities [2]. Specifically, the presence of rhamnose as terminal glycosidic unit can change the pharmacokinetic properties of therapeutic agents [3]. Rhamnose-capped molecules appear to be resistant to hydrolysis in human tissues due to the absence of endogenous rutinosidases and α-L- rhamnosidases. Thus, the rhamnose-capped molecules can be targeted where L-rhamnose receptors are located in order to enhance the pharmacological effects [4]. We have recently described a new α-L-rhamnosyl-β-D-glucosidases from the fungus Sarocladium strictum DMci 093557. The enzyme was able to hydrolyze 7-O-β-rutinosyl- and 3-O-β-rutinosyl- flavonoids and it also exhibited transglycosylation activities, transferring rutinose from rutin onto a broad spectrum of alcoholic acceptors, primary, secondary and phenolic alcohols. Remarkably, the rutinosylation of short chains length alcohols (methanol, ethanol) was not detected, while butanol, Isoamyl alcohol and phenolic acceptors such as resveratrol, 4-methylumbelliferone, resorcinol and phloroglucinol, were rutinosylated with reasonable yields. The antitumoral effects of the synthesized rutinosides, was assessed on cancer cell lines.