Tesis Doctorado
Blue bioprocess development of nutraceutics from marine red algae
Autor
Castro Varela, Pablo Andrés
Institución
Resumen
Sarcopeltis skottsbergii is an endemic red alga species of the Southern Cone, with biliproteins as
accessory pigments including R-phycoerythrin (R-PE). The production of S. skottsbergii is around 20,000 tons of
dry alga per year. The evaluation of R-PE in a biorefinery model is still in the early stages in the field of algal
biotechnology to be used in the food, pharmaceutical, cosmeceutical and nutraceutical industries. The objective of
this Thesis is to present the current knowledge and the exploration of novel applications, encouraging the rational
and integral utilization of this commercial specie. The Thesis is organized into six sections, covering information on
the processing technologies for extraction (HPH and UAE) and protection (alginate/shellac by ionic gelation) of RPE
and fractions for functional foods and nutraceuticals, the in vitro and in vivo assessment of the biological
activities, and alternative intensive production culture systems based on yellow light to saturate photosynthesis
supplemented by blue light for R-PE accumulation. HPH method was the most efficient extraction method of R-PE.
Furthermore, R-PE showed a positive correlation between the oxygen radical absorbance capacity (ORAC) in the
best-selected extractions. An attractive non-aggressive extraction alternative with the biological activity of interest is
suggested. From the residual supernatant generated by high-pressure homogenization, two soluble polysaccharides
(neutral and acid fractions) were obtained with high biological activity. The acid polysaccharides, which had a
relatively high sulfate content, exhibited significant antioxidant activity in superoxide radical assay (ABTS) and high
anti-proliferative effects on melanoma (G-361), leukemia (U-937) and colon (HCT-116) carcinoma cells. The in vivo
assay with zebrafish has shown a linear relationship between neutral and acid fractions concentration and growth
retardation at 72 hpf mg-1 ml-1 with a LC50 of about 1.45 mg ml-1 and 1.25 mg ml-1, respectively. These results
indicated that the in vitro antitumoral assays, in vivo model and antioxidant activities of the two polysaccharides may
be related to the combined effects of sulfate or galactose contents.
The encapsulation of alginate/shellac reached an EE value of 97.5% and led to higher R-PE contents at the end of
digestion compared with R-PE non-encapsulated, suggesting a protective role. From permeate streams, equivalent
to the absorption of R-PE encapsulated, the bioavailability was 2.5 times significantly higher than R-PE nonencapsulated.
A high selectivity index (> 10) was observed for the R-PE extract on the HCT-116 human colon
cancer cell line. The alginate/shellac as a wall material and ionic gelation technology used may determine the
release of the R-PE pigment at an intestinal site and their effect antiproliferative on health. Yellow light with the
incidence of blue light as an interesting factor in the culture of red microalgae improves high-quality R-PE compound
and maintained stable biomass productivity, to improve the quality of bioprocess production for nutraceutical
industry. This Thesis complemented understanding the potential of algae for traditional and novel functional
products. Agradezco a la Agencia Nacional de Investigación y Desarrollo de Chile (ANID) por la Beca Doctorado concedida (N°21180254) para la realización de esta tesis doctoral. RESULTADOS DEL CAPITULO IV (CHAPTER IV) DE LA TESIS DOCTORAL SON DE INTERES DE PROTECCION INTELECTUAL POR AMBOS CENTROS DE ESTUDIO ( UNIVERSIDAD DE LA FRONTERA Y UNIVERSIDAD DE MÁLAGA).
LA OFICINA DE TRANSFERENCIA TECNOLÓGICA DE LA UNIVERSIDAD DE LA FRONTERA SE ENCUENTRA LIDERANDO EL PROCESO. LA CUAL ESTÁ REALIZANDO ESTUDIO DE PATENTABILIDAD.
POR LO TANTO SE SOLICITAR LIMITAR EL ACCESO PUBLICO POR UN PERIODO DE 12 MESES A CONTAR DE LA FECHA DE DEPOSITO EN REPOSITORIO ANID