Guillermo Pascual

Prof. Dr. Guillermo Pascual

Universadad de Concepción
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 March 2021 in Processes
Verified
Journal Article
Open access
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María Dolores LópezMaría Dolores López
María Dolores López
ECEsteban F. Caamaño
Esteban F. Caamaño
Guillermo PascualGuillermo Pascual
Guillermo Pascual
FNFelipe Noriega
Felipe Noriega
PFPaulo Fierro-Morales
Paulo Fierro-Morales
Diego A. Moreno-FernandezDiego A. Moreno-Fernandez
Diego A. Moreno-Fernandez
This research was focused on developing means of Tintorera grape (Vitis vinifera L.) waste recovery, devising new value-added uses for that material and optimizing of anthocyanin-rich formulations by spray-drying in order to obtain novel ingredients, all for food industry use. First, the identification of phenolic compounds in Tintorera grape extracts by HPLC-DAD-ESI-MSn enabled characterization of the raw material’s health-promoting characteristics. Maintaining the spray-dried products for 4 weeks’ storage enabled study of the formulation’s loss of anthocyanins and antioxidant properties due to drying process temperatures as well as analysis of the retention and stability of such compounds under different conditions (20 and 40 °C). Tintorera grapes presented a significant amount of Malvidin 3-O-hex (5.66 mg g−1 DW). Anthocyanins in spray-dried formulations were stable for 4 weeks. Optimal conditions in the spray-dryer facilitated the products’ antioxidant capacity; for instance, using 10% maltodextrin (w:v) at 90 °C inlet temperature had a little influence on the reduction in encapsulated malvidin 3-O-hex (15%) and presented 3.35 mg GAE g−1 DW of total polyphenol contents, 98.62 µmol Trolox (FRAP assay), and 39.97 µmol Trolox (DPPH assay). Principal component analyses (PCA) showed a high degree of dependence between anthocyanin content and maintenance of antioxidant capacity during storage. These results offer a promising alternative for the industrial management of wine-making wastes in order to implement a sustainable protocol for development of Tintorera grape extracts rich in bioactive compounds for new beverages and functional foods.

1 January 2017 in Chilean journal of agricultural research
Verified
Journal Article
Open access
Guillermo PascualGuillermo Pascual
Guillermo Pascual
ISIgnacio Serra
Ignacio Serra
Arturo Calderon-OrellanaArturo Calderon-Orellana
Arturo Calderon-Orellana
VLV. Felipe Laurie
V. Felipe Laurie
María Dolores LópezMaría Dolores López
María Dolores López

27 December 2022 in Antioxidants
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Journal Article
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Guillermo PascualGuillermo Pascual
Guillermo Pascual
DSDiego Silva
Diego Silva
MVMarisol Vargas
Marisol Vargas
MAMario Aranda
Mario Aranda
JCJuan Antonio Cañumir
Juan Antonio Cañumir
María Dolores LópezMaría Dolores López
María Dolores López
Ingredients rich in phenolic compounds and antioxidants of winemaking wastes, which play an important role in the prevention of various diseases and the control of viruses, are being explored. Currently, there is a concern about honeybee population loss, with deformed wing virus (DWV) being the most common virus infecting apiaries and one of the main causes of honeybee decline. Hence, the effect of grape pomace powder (GPP) as a dietary supplement to enhance the immune system of honeybees affected by DWV was evaluated. The characteristics of the ingredient GPP, obtained by spray-drying, revealed a high anthocyanin content (1102.45 mg 100 g−1), and it was applied at doses of 0.5, 1, 2.5 and 5% as a dietary supplement for bees infected by DWV. The results showed that the GPP treatments strengthened the immune response of honeybees against DWV. Moreover, the expression of the Relish gene was significantly higher in bees fed with GPP compared to the infected control. This study, which is framed in the search of food waste valorization for environmental sustainability, proves the feasibility of using grape wastes as dietary supplements for pollinators, and provides knowledge of the influence of polyphenols on the expression profiles of immune-related genes in honeybees.

16 September 2021 in Processes
Verified
Journal Article
Open access
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WIWalther Ide
Walther Ide
CSConstanza Sabando
Constanza Sabando
JCJohanna Castaño
Johanna Castaño
NPNatalia Pettinelli
Natalia Pettinelli
RBRichard Bustos
Richard Bustos
SRSaddys Rodríguez-Llamazares
Saddys Rodríguez-Llamazares
Vitis vinifera L. cv. País is an ancestral Chilean grape undervalued due to its undesirable oenological characteristics. In this study, steam extraction for the production of grape juice, a new product, according to our knowledge, is proposed as an alternative for the valorization of this fruit. The effect of the extraction time on the composition and antioxidant capacity of País grape juice obtained was evaluated, as well as the change in the phenolic profile during storage. The soluble solid values and total polyphenol and total anthocyanin content increased with the extraction time. However, a residence time of the juice in the extraction device higher than 10 min led to thermal degradation of anthocyanins and flavonols. The most abundant phenolic compound identified and quantified by HPLC-DAD in the País grape juice was cinnamic acid. The storage of juices had a greater effect on anthocyanin and flavonol losses than the residence time of the juice in the extraction device. The antioxidant capacity of juice measured by ABTS and ferric reducing power assays ranged from 3 to 5 mmol trolox/L and from 10 to 18 mM Fe2+/L, respectively. In summary, steam extraction is a viable method to produce País grape juice with antioxidant capacity.


29 May 2022 in Foods
Verified
Journal Article
Open access
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Guillermo PascualGuillermo Pascual
Guillermo Pascual
María Dolores LópezMaría Dolores López
María Dolores López
MVMarisol Vargas
Marisol Vargas
MAMario Aranda
Mario Aranda
JCJuan Antonio Cañumir
Juan Antonio Cañumir
Management of waste and use of winemaking by-products plays an important role in the development of new ingredients, especially with antiviral properties. Although the richness of bioactive compounds from wine waste is known, less is known about potential antiviral action. Bioactive compounds and health-enhancing effects of winery by-products make them potential candidates for use in antiviral ingredients. The design of new formulations by using nano-microencapsulation techniques will be necessary to successfully control diseases produced by viruses. Outcomes about the use of winery by-products, bioactive compounds found in winery wastes, green extraction techniques to concentrate these compounds, and development of formulations to obtain new ingredients were extracted from research around the world to be discussed and updated in this manuscript. The evidence collected in this review aims to encourage transfer of in vitro and in vivo knowledge to a new step for the development of antiviral and treatments.