Thalassia testudinum

Zidorn, Christian, 2016, Secondary metabolites of seagrasses (Alismatales and Potamogetonales; Alismatidae): Chemical diversity, bioactivity, and ecological function, Phytochemistry 124, pp. 5-28 : 22

4.10. Development of an herbal medicine from T. testudinum

Rodeiro et al. (2008a) demonstrated that T. testudinum extracts had only marginal cytotoxicity towards rat hepatocytes and did not significantly interfere with P450 enzymes. Moreover, Rodeiro et al. (2008b) demonstrated that T. testudinum extracts had moderate in vivo hepatoprotective effects versus several standard hepatotoxins. Rodeiro et al. (2009) later reported inhibition of CYP1A1/2 and 3A4 but not CYP2D6 activity by T. testudinum extracts and cautioned that this could potentially induce herbal-drug interactions when using Thalassia based medical products. This preliminary study was followed by a more detailed study ( Rodeiro et al., 2012) confirming previous results and adding additional detailed knowledge for more enzymes and also for the in vitro activity of the main metabolite thalassiolin B 71.

Regalado et al. (2009) reported dose-dependent recovery of UVB damaged mouse skin when applying an aqueous ethanolic extract of T. testudinum . Regalado et al. (2011) while studying the apolar compounds of T. testudinum leaf extract also proved the ability of these apolar compounds to decrease visible and histological alteration of mouse skin irradiated with UV-B by attenuating the oxidative stress caused by UV-B radiation during the first hours after irradiation.

Based on these bioactivity studies, a standardized aqueous/ ethanol extract of T. testudinum leaves (BM-21) is being developed in Cuba as an herbal medicine ( Regalado et al., 2012). In this context, the antioxidant activity of BM-21 was evaluated ( Regalado et al., 2012). Moreover, anti-nociceptive activity of the extract and its main phenolic, 71, was assessed and potency and concentration of 71 made it plausible that this compound accounted for most of the activity found for the extract ( Garateix et al., 2011). Menéndez et al. (2014) investigated neuroprotective and antioxidant effects of BM-21 using the acrylamide-induced mice neurotoxicity model. The authors reported significant and dose-dependent activity in orally administered extract and explain the activity of the extract with its anti-oxidative properties. Ansoar et al. (2014) using a S. typhimurium based experimental assay, found no hints for mutagenic or genotoxic actions of the standardized BM-21 extract. Also teratogenic and embryotoxic activities of BM-21 were ruled out based on experiments with Wistar rats ( de la Torre Núñez et al., 2014). The Cuban research efforts on T. testudinum and on the bioactivities of BM- 21 in particular were summarized by de la Torre Núñez et al. (2012).