Biomass, sinensetin content, and α-glucosidase inhibition activity of orthosiphon aristatus were influenced by fertilization and harvest

Abstract

Orthosiphon aristatus has been proved as a diabetic remedy due to its anti-hyperglycemic activity. One of its phenolic compounds, sinensetin, has a capability to inhibit α-glucosidase enzyme activity. As cultivation techniques play roles in the medicinal properties of plants, this study was aimed to determine the best fertilization and harvest method to obtain the high yield of dry leaves, sinensetin content and α-glucosidase inhibition activity. The experiment was conducted at Leuwikopo Experimental Farm IPB University, from October 2014 until April 2015 and used a split-split plot design with three replications. The treatments were the technique of organic fertilizer application (whole and split) as the main plot; harvest interval (3, 5 and 7 weeks) as subplot; and cutting height (10, 20 and 30 cm above ground level) as sub-sub plot. The results showed that the whole application of 10 ton ha−1 organic fertilizer produced the higher weight of O. aristatus dry leaves than split application. The crop produced a high weight of dry leaves with the 3- and 5-week harvest interval but produced high sinensetin content with the 7-week harvest interval. O. aristatus harvested by cutting at 30 cm above ground level produced the highest weight of dry leaves, sinensetin content and α-glucosidase activity inhibition.