Gastroprotective Activity of Myrtenol Derivatives Obtained by Biocatalytic Esterification and Photooxidation.

Many naturally occurring substances exhibit anti-ulcer properties. One promising area of research is the identification of terpenoid compounds with enhanced therapeutic and gastroprotective properties. The present study aimed to synthesize new terpenoid derivatives of myrtenol via biotransformation using freeze-dried Cladosporium cladosporioides mycelium or via porphyrin-based biomimetic transformation, and to evaluate their gastroprotective activity in an ethanol-induced gastric lesion model. Five myrtenyl esters (acetate, butyrate, caprylate, pelargonate, and laurate) and two oxidative derivatives (myrtenal and myrtenal oxide) were obtained with a high degree of purity (> 94%, GC). The anti-ulcer preventive effects of the compounds were evaluated in mice at doses ranging from 6.25 to 25 mg per kg of body weight. The mice were treated orally prior to the induction of ethanol-induced gastric lesions. All compounds exerted a gastroprotective effect, reducing the lesion area (mm2) compared to the negative control group. Notably, the gastroprotective effects of myrtenyl caprylate, myrtenyl pelargonate, and myrtenyl laurate were equivalent to those promoted by the clinical medicine pantoprazole.