The impact of extraction method and solvent on biological activities of garlic extract

Garlic is a medicinal plant that is widely used as an ingredient in traditional medicine in Indonesia. Scientifically, garlic extract has the ability as an antioxidant, antibacterial, anticancer, and antihypertensive. The use of different extraction techniques and solvents will give different results on the amount and biological activity of the extract. This study aims to determine the biological activity of garlic extract using two extraction techniques and solvent types. The TEAC, FRAP, NO and DPPH scavenging assays were used to determine in vitro antioxidant activity. Follin-Ciocalteu reagent and aluminium chloride colorimetric assay were used to determine total phenolic (TPC) and flavonoid (TFC) content. In vitro disc diffusion, sulforhodamine B (SRB), and angiotensin converting enzyme (ACE) inhibition assays were used to determine the antibacterial, anticancer, and antihypertensive activities, respectively. The 70% ethanol solvent and maceration method had better antioxidant activity than the aqueous and ultrasonic-assisted extraction (UAE). TPC values were not significantly different between extraction methods and solvents in all treatments, meanwhile aqueous solvent gave better TFC values than 70% ethanol. Garlic extract only had inhibition against B. subtilis bacteria. The anticancer against MDA-MB231 breast cancer cell line and ACE inhibitory activity of 70% ethanol solvent and UAE method was higher than that of aqueous and maceration. It can be concluded that the different solvent and extraction method were affecting on the biological activities of the garlic extract. However, the UAE technique provides a more effective extraction alternative that requires less solvent and a shorter time.