by Rita de Cássia de Souza 1, Bruna Aparecida Souza Machado 2*, Gabriele de Abreu Barreto 2, Ingrid Lessa Leal 2, Jeancarlo Pereira dos Anjos 2ORCID andMarcelo Andrés Umsza-Guez 1
1 Federal University of Bahia, Bahia, Salvador 40170-115, Brazil
2 University Center SENAI CIMATEC, SENAI Institute of Innovation (ISI) in Advanced Health Systems (CIMATEC ISI SAS), National Service of Industrial Learning–SENAI, Bahia, Salvador 41650-010, Brazil
*Author to whom correspondence should be addressed.
Molecules 2020, 25(7), 1634; https://doi.org/10.3390/molecules25071634
Submission received: 26 February 2020 / Revised: 23 March 2020 / Accepted: 26 March 2020 / Published: 2 April 2020
(This article belongs to the Special Issue Technologies for Extraction of Bioactive Compounds from Natural Sources and Their Applications as Cosmeceuticals, Nutraceuticals and Food Ingredients)
Abstract
Grape seeds are an important byproduct from the grape process. The objective of this work was to evaluate the effect of experimental parameters (temperature and time of pretreatment with ultrasound) to obtain grape seed oil using low pressure (Soxhlet-Sox and Bligh Dyer-BD) and high pressure (supercritical carbon dioxide-SFE) methods. The best condition for pretreatment of samples was 30 min of sonication at 30 °C before extraction by Sox or BD. Ultrasound pretreatment was efficient to increase oil extraction yield by 32.10 (Sox), 20.31 (BD) and 12.54% (SFE), depending on the extraction method used as well as, and certainly influenced the total phenolic concentration in 311 (Sox), 234 (BD), and 184 (SFE)%. Ten fatty acids were identified in the oils, the major ones being 18:2ω-6cis (linoleic 52.39%–63.12%), 16:0 (palmitic 20.22%–26.80%) and 18:0 (stearic 8.52%–13.68%). The highest epicatechin concentration was identified in the BD sample: 30-30 (150.49 ± 5.98mg/kg), which presented a concentration of ≥3 times compared to the control (56.68 ± 1.81mg/kg). Ultrasound pretreatment also contributed positively (56% and 99% increase) in the α-tocopherol content of the SFE: 30-30 and BD: 30-30 samples, respectively. The results indicate that the ultrasound pretreatment is a suitable technology to improve the quality of the oil from the grape seed.
Keywords: Vitis vinifera; cold extraction; α-tocopherol; supercritical CO2 extraction; agro-industrial waste