European Journal of Biomedical and Pharmaceutical Sciences

ASSESSMENT OF ULTRASOUND EXTRACTION FOR THE RECOVERY OF PHENOLIC COMPOUNDS FROM OPUNTIA STRICTA PEEL: EVALUATION OF ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES

K. El mahtal, S. Lairini, M. Boudkhili*, R. Bouslamti, M. Errbii and S. Guissi

ABSTRACT

By-products generated at high quantities by food industries are generally discarded, giving rise to environmental pollution worldwide. However, these could serve as abundant source of valuable bioactive compounds. In the present work, extracts of Moroccan Opuntia stricta peel was subjected to evaluation as a potential source of antioxidants. For this purpose, different extraction techniques (conventional maceration, Soxhlet extraction and ultrasonic extraction) were compared in terms of process global yield, total phenolic (TPC) and flavonoids contents (TFC). Moreover, the extract obtained by the most effective extraction method was then tested for its antioxidant and antimicrobial activities. The high total phenolic content (76.29 mg of gallic acid equivalent/100 g), flavanoids concentration (24.97 mg of quercetin equivalent /100 g) and extraction yield (12.26%) obtained from UAE proved its efficiency when compared with the other tested methods. Antioxidant activity of the UAE extract (IC50=150μg/mL) was very high, similar to that of butylated hydroxyanisole (BHA). Antibacterial study showed that Streptococcus pneumoniae and Pseudomonas aeruginosa were more sensitive to the extract then the tested bacterial strains with a Minimal Bactericidal Concentration (MBC) of 160 μg/mL. Overall; these results showed promising prospects for future exploitation of Opuntia stricta peel as a functional food ingredient and/or supplement.

Keywords: Opuntia stricta, Streptococcus pneumoniae and Pseudomonas aeruginosa.