Background: Agarwood (Aquilaria malaccensis Lamk.) Contains flavonoids, alkaloids, terpenoids, steroids, and saponins that can function as bioreduction in the Greensynthesis nanosilver. Objective: The aims of this study to determine the effect of the concentration of liquid extract of agarwood leaves in the synthesis of nanosilver (AgNPs) using the green synthesis method. Materials and Methods: The concentration of liquid extract of agarwood leaves used in the synthesis of nanosilver in formulas I, II, and III was 25, 50, and 75 mg/ml. Nanosilver characterization includes surface plasmon resonance (SPR), which was analyzed by looking at the spectra profile using UV-vis spectroscopy at wavelengths of 300 to 700 nm. The particle size and potential zeta of AgNPs were analyzed using Particle Size Analysis. Results: Variation in concentration of liquid extract of agarwood leaves can produce color changes from yellowish to brown with SPR values ​​418 - 436 nm. The particle size produced formulas I, II, and III are 76.5; 45.70; 77.95 nm. Potential zeta value at FI -26.93 mV; FII -22.72 mV; F III -33.67 mV. Conclusion: Based on the results showed that the variations in the concentration of liquid extract of agarwood leaves were 25, 50, and 75 mg/ml capable of producing nanosilver preparations.

Keywords: agarwood, bioreduction, green synthesis, nanosilver