The production of biodiesel was carried out from canola oil and methanol catalysed by lipase from
Candida rugosa under different ultrasonic experimental conditions using horn (20 kHz) and plate (22,
44, 98 and 300 kHz) transducers. The effects of experimental conditions such as horn tip diameter, ultrasonic
power, ultrasonic frequency and enzyme concentrations on biodiesel yield were investigated. The
results showed that the application of ultrasound decreased the reaction time from 22–24 h to 1.5 h with
the use of 3.5 cm ultrasonic horn, an applied power of 40 W, methanol to oil molar ratio of 5:1 and
enzyme concentration of 0.23 wt/wt% of oil. Low intensity ultrasound is efficient and a promising tool
for the enzyme catalysed biodiesel synthesis as higher intensities tend to inactivate the enzyme and
reduce its efficiency.