Preparation of andrographolide-enriched extract of A. paniculata leaves:
A. paniculata (Burm. f.) Nees was collected in August 2012 from the area around Yogyakarta, Indonesia.
The leaves were shade dried, powdered and stored in an airtight container for further use.
The plant was authenticated by a botanist at Department of Pharmaceutical Biology, Faculty of Pharmacy, Universitas Gadjah Mada, Indonesia and the voucher specimen was deposited in herbarium of the department.
The dried powder of A. paniculata (Burm. f.) Nees was subjected to extraction using 90% ethanol for 24 h.
After filtration, the liquid extract was collected.
The sediment was re-extracted using the same solvents for 24 h. This process was done twice.
All liquid extracts were collected and concentrated using a rotary vacuum evaporator under reduced pressure.
The extract was then fractionated with n-hexane at a ratio of 1:10 (extract:n-hexane) yielding two fractions of hexane soluble fraction and insoluble fraction.
The insoluble fraction was collected and then evaporated to obtain viscous extract.
The insoluble fraction was then washed with hot water and diluted with ethanol 90% to yield an andrographolide-enriched extract of 1.71%, with andrographolide level of 16.31%. The andrographolide was identified using HPLC-UV compared to a standard andrographolide (Sigma-Aldrich, USA).
The quantification of andrographolide was performed using TLC-Densitometry method.