Identification of some Opuntiaspp. from two Algerian regions and ultrasound assisted extraction of their phenolic compounds

Abstract

Much attention has been paid to cacti for their distinctive characteristics. The nopal Opuntiaficus-indicaand relatedspecies are found inarid and semi-arid regions around the world. O.ficus-indica shows considerable variability in response to environmental conditions through variation of areola and spine attributes, among other traits. Therefore, the present study sought to morphologically identify some cactuspear plants in two areas of Algeria (Bejaia and Souk-Ahras)in orderto evaluate the cactus pears by optimizing the extraction conditions of the phenolic compounds of the cladode, to evaluate the antioxidant activity of these compounds,to measure the total flavonoid content,and to compare the yields among three Opuntiaspp. (O. ficus-indica, O. megacanthaand O. amyclae) from the sites within the study regions. These three Opuntiaspp. were subjected to extraction of polyphenols using a conventional method, and an ecofriendly process using ultrasound-assisted extraction(UAE)technique.Once the extractionswas completed, the total phenolic contentandflavonoids of the extracts were characterized. In addition, the antioxidant capacityof the total phenolic compounds (TPC)wasdetermined. The UAEwas better than conventional extraction for the recovery of TPC. The use of a solvent mixture (50% water/ethanol, v/v) improved the TPC extraction efficiency. Theseresults show thatUAE was a useful tool for the extraction of phytochemicals from cactuspear cladodes. Other factors and conditions that influence the optimization of TPC extractionshould also be studied, such as pH, ultrasound frequencyas well asecological factors that could possibly influence extraction efficiency