Assessment of chemical, biological and immunological properties of "Damiana de California" Turnera diffusa Willd extracts in Longfin yellow tail (Seriola rivoliana)leukocytes

In Mexican herbal medicines or natural remedies, Turnera diffusa (Turneraceae)known as "Damiana de California", has ethnopharmacological relevance, including aphrodisiac, diuretic, and antimicrobial activities. To explore the immunological effect of infusion and methanolic extracts from Damiana de California, this study investigated its chemical, biological, antimicrobial and immunological properties in Longfin yellowtailSeriola rivoliana leukocytes. The analysis of chemical compounds revealed a considerable level of total phenolic and flavonoid contents in the infusion compared with methanolic extract. Furthermore, the antioxidant activity showed high hydroxyl radical scavenging activity in infusion extract compared with BHT positive control. Superoxide radical scavenging activity and ion chelation were higher in methanolic extract followed by infusion treatment. Interestingly, notable antimicrobial activity was observed in both extracts of T. diffusa against Vibrio parahaemolyticus.Anin vitro study was performed using leukocytes ofS. rivolianatreated with infusion or methanolic extracts at 12.5, 25 and 50µg/mL for 24 h. Remarkably, infusion extract induced proliferation at any concentration but not the methanolic extract, which was diminished in a dose-dependent fashion. Theimmunostimulation study demonstrated that the phagocytosis activity increased in those leukocytes stimulated with methanolic extract but diminished the respiratory burst activity, in contrast to the activity observed in those leukocytes stimulated with infusion treatment. Finally, leukocytes incubated with the extracts and confronted withV. parahaemolyticusup-regulated the transcription of proinflammatory cytokine IL-1ßgene in a dose response relationship. These findings suggest that the infusion treatment has potential therapeutic properties, promoting the antioxidant capacity and enhancing immune parameters in Longfin yellowtailS. rivoliana.