Analysis of the phenol and flavonoid content from basil leaves (Ocimum americanum L) extract using pulsed electric field (PEF) pre-treatment

Basil leaves (Ocimum Americanum Linn) are commonly known to contain phenol and flavonoid compounds which can act as antimicrobial and antioxidants. In general, the bioactive compound can be obtained by conventional extraction method, maceration. To increase the amount of bioactive compounds which can be extracted, it is necessary to conduct pre-treatment using pulsed electric field (PEF). PEF has an advantage in increasing the compound transfer contained in cells to be extracted from the plant tissues via electroporation mechanisms, without causing significant temperature changes. This study aims to determine the effect of electric field strength variations (2, 3, and 4 kV cm^-1) and duration of pre-treatment (1, 2, and 3 mins) to total phenol and flavonoid content of basil leaf (Ocimum Americanum Linn) extract. The result of statistical analysis using two-way analysis of variance informs that electric field strength variation, pre-treatment duration, and interaction of both variables simultaneously affect the total level of phenols and flavonoids. The combined treatment of 3 kV cm^-1 and the two-minute pre-treatment duration results in the highest total phenol and flavonoid level, i.e. 115.203±1.115 mg gallic acid equivalents (GAE)/g extract and 75.816±0.723 mg quercetin equivalents (QE)/g extract respectively. The extraction utilizing PEF treatment also exhibits higher levels of phenol and flavonoid than those of control treatment.