TY - JOUR
T1 - Pressurized Liquid Extraction Optimization from Supercritical Defatted Olive Pomace
T2 - A Green and Selective Phenolic Extraction Process
AU - Katsinas, Nikolaos
AU - Bento Da Silva, Andreia
AU - Enríquez-De-Salamanca, Amalia
AU - Fernández, Naiara
AU - Bronze, Maria Rosário
AU - Rodríguez-Rojo, Soraya
N1 - info:eu-repo/grantAgreement/EC/H2020/765608/EU#
H2020-MSCA-ITN-2017
01 0145 FEDER 402 022125
PY - 2021/4/26
Y1 - 2021/4/26
N2 - Olive pomace (OP) is the main by-product of the olive oil industry produced in large quantities. Its valorization as a source of phenolic bioactive compounds is paramount for the sustainable growth of related industries. This work proposes an intensified process to maximize the recovery of phenolic compounds in dry extracts using hydroalcoholic mixtures. Supercritical carbon dioxide defatting pre-treatment was performed. Following this, pressurized liquid extraction was optimized through a circumscribed central composite design. The factors consisted of temperature (65.0-185.0 °C), ethanol percentage (8.0-92.0%), and solid/liquid ratio (0.2-0.8 gOP/mLSOLVENT). Besides the total phenolic content (TPC) and the total flavonoid content (TFC), the major phenolic compounds of OP [hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OL)] were evaluated. Further, decarboxymethyl OL aglycone dialdehyde (3,4-DHPEA-DEDA) was identified by HPLC-DAD-MS/MS as the most abundant polyphenol and was studied for the first time for OP. Different conditions were found to optimize each key compound. In 67% shorter extraction time and 38% less solvent consumption compared to conventional extraction, an increase of 475% for OL, 428% for HT, 194% for TY, 373% for 3,4-DHPEA-DEDA, 89% for TPC, and 158% for TFC was observed. The antioxidant activity by oxygen radical absorbance capacity (ORAC) assay increased 89% (optimal conditions) and correlated with TPC, 3,4-DHPEA-DEDA, and TFC. Thus, an efficient, selective, scalable, and green extraction process was established.
AB - Olive pomace (OP) is the main by-product of the olive oil industry produced in large quantities. Its valorization as a source of phenolic bioactive compounds is paramount for the sustainable growth of related industries. This work proposes an intensified process to maximize the recovery of phenolic compounds in dry extracts using hydroalcoholic mixtures. Supercritical carbon dioxide defatting pre-treatment was performed. Following this, pressurized liquid extraction was optimized through a circumscribed central composite design. The factors consisted of temperature (65.0-185.0 °C), ethanol percentage (8.0-92.0%), and solid/liquid ratio (0.2-0.8 gOP/mLSOLVENT). Besides the total phenolic content (TPC) and the total flavonoid content (TFC), the major phenolic compounds of OP [hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OL)] were evaluated. Further, decarboxymethyl OL aglycone dialdehyde (3,4-DHPEA-DEDA) was identified by HPLC-DAD-MS/MS as the most abundant polyphenol and was studied for the first time for OP. Different conditions were found to optimize each key compound. In 67% shorter extraction time and 38% less solvent consumption compared to conventional extraction, an increase of 475% for OL, 428% for HT, 194% for TY, 373% for 3,4-DHPEA-DEDA, 89% for TPC, and 158% for TFC was observed. The antioxidant activity by oxygen radical absorbance capacity (ORAC) assay increased 89% (optimal conditions) and correlated with TPC, 3,4-DHPEA-DEDA, and TFC. Thus, an efficient, selective, scalable, and green extraction process was established.
KW - antioxidant capacity
KW - decarboxymethyl oleuropein aglycone dialdehyde (oleacein)
KW - hydroxytyrosol
KW - oleuropein
KW - olive pomace phenolic compounds
KW - pressurized fluid extraction
UR - http://www.scopus.com/inward/record.url?scp=85105105729&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.0c09426
DO - 10.1021/acssuschemeng.0c09426
M3 - Article
AN - SCOPUS:85105105729
SN - 2168-0485
VL - 9
SP - 5590
EP - 5602
JO - ACS Sustainable Chemistry & Engineering
JF - ACS Sustainable Chemistry & Engineering
IS - 16
ER -