Title : Development of microparticles loaded with pine bark extracts and evaluation of its bioavailability on fish
Avoiding wounds in salmon and trout farming systems is an important need of the industry, due their potential production decline effect, caused by decrease of fish meat quality, and the consequent profits loss of the companies. The High frequency of wounds in intensive farming, added to their role in the generation of diseases and the current absence of additives to favor the healing process led us to propose the following solution to this problem. We developed a new fish food additive, which contains natural bioactive components obtained from pine bark, which will generate positive effects on fish health; providing prophylactic protection against diseases and also allowing better and faster healing of wounds. In order to get this objective, we stabilized a natural pine bark (Pinus radiata) extract on biocompatible polymers, developing six different microparticles and then we evaluated the bioavailability of two of these formulations in trouts (100-150 g). Taxifolin is a subunit of flavonol present in P. radiata bark extracts, this molecule was chosen as the polyphenolic compounds absorption marker for the in vivo tests. In a first stage, the validation of the analytical methodology for the quantification of Taxifolin in plasma was done by HPLC (to ng level). After that, taxifolin quantification in fish plasma was used as marker of extracts bioavailability. The absorption kinetics of the phenolic compounds stabilized in two microparticles types was determinated, sampling plasma during 48 h. Results indicated plasma of trout that received microencapsulated extract, reached a taxifolin concentration 25% higher than the ones that recieved the raw extract, for the same initial dosis of ingest. Also, the release of the active compound was more prolonged over time in the microencapulted samples, observing levels of taxifolin in the blood for longer periods that the raw extract. No taxifolin was detected after 18 h from the administration of the treatments and no citotoxic effects were observed on fish. This additive can be a contribution to the development of fish farming in general. Takeaway Notes: •To develop new polymeric matrices to immobilize natural compounds, whose developed is scares. •To use bark, which is a byproduct of forest industry and is considered a waste, for the production of a functional food. •To know how to evaluate the in vivo bioavailability of a natural compound.