In this analysis, 10 mg of b-sitosterol standard was dissolved in a few drops of PA-grade chloroform and then supplemented with HPLC-grade methanol to reach a final volume of 10 mL. This solution was then prepared as a stock solution at a concentration of 1000 ppm, and further dilutions were made as needed using HPLCgrade methanol until the desired concentrations were achieved. All solutions with varying concentrations were filtered through a 0.22 µm PTFE filter before being injected into the HPLC system. HPLC analysis was performed at a flow rate of 1 mL/minute, using a mobile phase composed of methanol:acetonitrile (9:1, v/v), C18 stationary phase, and a wavelength of 202 nm to detect b-sitosterol (Khonsa et al., 2022) (link). After obtaining the peak areas from the HPLC analysis, a graph was constructed by plotting the concentrations of the standard b-sitosterol solutions (x-axis) against the corresponding peak areas (y-axis). The resulting line equation became the standard curve for b-sitosterol.
For the analysis of b-sitosterol content in the dry extract of Javanese ginseng roots, the extract was initially dissolved in 5 mL HPLC-grade methanol. Subsequently, the extract solution was filtered through a 0.22 µm PTFE filter into an HPLC vial, reaching a final volume of 1.5 mL. This solution was then injected into the HPLC instrument using the same HPLC settings as those used for the analysis of standard b-sitosterol solutions of various concentrations. The peak area obtained from HPLC analysis was used as the y-value in the standard curve equation to determine the concentration of bsitosterol in the sample as the x-value.
The concentration of b-sitosterol was then converted into the b-sitosterol content in the root extract using Eq. ( 5) (Fuentes-Arderiu, 2013). where C(SIT) represents the concentration of b-sitosterol, Vs is the solvent volume (HPLC-grade methanol), and RPW is the weight of root powder used for one-sample replication. Furthermore, the bsitosterol productivity of the roots was calculated using Eq. ( 6) (Mangoli, 2020) . In calculating the b-sitosterol productivity from the roots, we assumed the dimensions of the hydroponic gully to be 2.1 m x 0.58 m (length x width) with a total of 48 plants in each hydroponic set.
For the analysis of b-sitosterol content in the dry extract of Javanese ginseng roots, the extract was initially dissolved in 5 mL HPLC-grade methanol. Subsequently, the extract solution was filtered through a 0.22 µm PTFE filter into an HPLC vial, reaching a final volume of 1.5 mL. This solution was then injected into the HPLC instrument using the same HPLC settings as those used for the analysis of standard b-sitosterol solutions of various concentrations. The peak area obtained from HPLC analysis was used as the y-value in the standard curve equation to determine the concentration of bsitosterol in the sample as the x-value.
The concentration of b-sitosterol was then converted into the b-sitosterol content in the root extract using Eq. ( 5) (Fuentes-Arderiu, 2013). where C(SIT) represents the concentration of b-sitosterol, Vs is the solvent volume (HPLC-grade methanol), and RPW is the weight of root powder used for one-sample replication. Furthermore, the bsitosterol productivity of the roots was calculated using Eq. ( 6) (Mangoli, 2020) . In calculating the b-sitosterol productivity from the roots, we assumed the dimensions of the hydroponic gully to be 2.1 m x 0.58 m (length x width) with a total of 48 plants in each hydroponic set.
