Effects of impregnate temperature on extraction of caffeoylquinic acid derivatives from Moringa oleifera leaves and evaluation of inhibitory activity on digestive enzyme, antioxidant, anti-proliferative and antibacterial activities of the extract

Summary In an ultrasonic bath and for 30 min in the presence of water as extraction solvent in a ratio of 1:10 (g/mL), effect of extraction temperature on extraction of caffeoylquinic acids (CQAs) from Moringa oleifera leaves (MOL) was investigated. Gradually increasing in extraction temperature caused a growing in mono-CQA and declining in 3,5-diCQA. The extract obtained at 80 °C showed the highest antioxidant capacity, and IC 50 values for scavenging activities on DPPH radicals and ABTS radicals were 56.9 and 53.6 µg/mL, respectively. Compared with α-glucosidase and α-amylase, the extract showed the highest inhibition on pancreatic lipase (IC 50 of 0.073 mg/mL). Increasing the extraction temperature improved cytotoxicity of the extract on cancer cell lines of HeLa and HepG2. Compared with gram-negative Escherichia coli and Salmonella typhimurium , all the extracts showed higher inhibition on the growth of gram-positive Bacillus cereus and Staphylococcus aureus . Our results suggested that use of higher extraction temperature (80 °C) improved the biological activity of MOL extract.