ABSTRACT
Calcium oxalate is one of the most common components in urolithiasis. Its treatment includes the
use of synthetic drugs, ultrasound and surgery. However, cheaper alternative treatment using
herbal medicine with less adverse side effect is preferred. Essential oils from Thai basil (Ocimum
bacilicum L.), Vietnamese coriander (Persicaria odorata) and Chinese parsley (Coriandum
sativum L.) were extracted and investigated for antiurolithic activity based on calcium oxalate
crystallisation. Most of the crystals formed in control sample were hexagonal calcium oxalate
monohydrate with sizes ranging between 3 to 4 m. The size of the crystals was found to be slightly
reduced in O. bacilicum oil (2-4 m) at high concentration with less aggregation of crystals.
Samples with P. odorata oil gave smaller crystal size (3 m) mainly in dehydrate form and the oil
was also found to inhibit the aggregation of the crystals at high concentration. C. sativum oil
enhanced crystallisation (5-6 m) with increased concentration and showed high aggregation of
the crystals. This preliminary study shows the therapeutic potential of these medicinal plants to be
used in traditional anti-urolithic therapy.