AGROBIOLOGIA
Volume 12, Numéro 2, Pages 3138-3151
2022-12-31

Evaluation Of Ultrasound And Pulsed Electric Field Assisted Extractions On The Biological Activities Of Chlorella Spp

Authors : Attal Fella-sara .

Abstract

Ultrasound (US) and pulsed electric field (PEF) treatments are widely used to disrupt living cells to enhance the extraction of bioactive compounds. The aim of the present work was to compare them for processing fresh water green alga Chlorella spp. native to Lake El-Golea in southern Algeria and grown under controlled conditions in the laboratory. Intracellular contents soluble in acetone, chloroform, ethanol, methanol, and distilled water were extracted in conjunction with US or PEF or just soaking in the solvent. The extracts were screened for phytochemical content and tested for antimicrobial and antioxidant activities. They were found to contain bioactive molecules such as tannins, carotenoids, flavonoids, alkaloids, chlorophylls, phenols, glycosides and reducing sugars. They inhibited the growth of Listeria innocua ,Staphylococcus aureus, and E. coli to varying degrees depending on the extraction process. Candida albicans, Saccharomyces cerevisiae, and Aspergillus niger were all sensitive to the extract obtained using chloroform. Extraction with ethanol or acetone gave the best biological activity results overall.PEF/ethanol and PEF/acetone extracts had the greatest antioxidant power. Pulsed electric field was the best enhancer of extraction of the biologically active substances, followed by ultrasound.

Keywords

Chlorella spp ; ultrasound ; pulsed electric field ; bioactive compounds ; biological activity