摘要
There is currently an increasing interest in obtaining bioactive components and natural pigments by novel extraction technologies.Betalains are plant-derived secondary metabolites with functional characteristics,suit-able for use in food products.Conventional(CE)and ultrasound-assisted extraction(UAE)have been studied to extract betalain-rich bioactive compounds from prickly pear fruit(Opuntia ficus-indica L.).Box-Behnken design was used in response surface methodology to predict the optimal conditions for each parameter based on total betalain content(TBC),total phenolic content(TPC),and antioxidant capacity(TAC).In addition,the antimi-crobial activity of the extracts at optimal conditions was investigated against Salmonella enteritidis(ATCC 13076),Escherichia coli O157:H7,and Listeria monocytogenes.Results indicated that optimal conditions for CE were achieved at 2.05-h extraction time,50℃,80%ethanol concentration,and a 1/22.60 solid/solvent ratio,while for UAE,optimal conditions were at 30-min extraction time,49.99℃,40%ethanol concentration,and a 1/30 solid/solvent ratio.The predicted and experimental TBC values for CE were 419.449 and 418.829 mg betalain/kg dry matter,respectively,and for UAE,they were 472.883 and 471.818 mg betalain/kg dry matter.The ex-tracts demonstrated antimicrobial activity solely against Salmonella enteritidis(ATCC 13076).UAE proved more efficient,extracting betalain-rich bioactive compounds in 75%less time compared to CE.Therefore,UAE emerges as a promising novel technology for obtaining natural pigments and bioactives from prickly pear.
基金
supported by The Scientific and Technological Research Council of Turkey(TUBITAK,Project no:222O444).
