Inhibition of struvite crystal growth in the presence of herbal extract Orthosiphon aristatus Bl.Miq

Abstract

The formation of urinary stones is a serious problem worldwide. Struvite (MgNH4PO4.6H2O) is known as one of the main components of the stones. Traditionally, herbal extracts treatment is recommended. This paper discussestheeffects of Orthosiphon aristatus Bl.Miq leaves extract (OA) on struvite crystals grown by diffusion gel method. After three weeks the crystals were separated from thegel, air dried and stored for characterisation. The crystals exhibit different morphologiesdepending upon the location of growth. It was found that OA caused the crystals to have noticeable surface defects, discolorisation and fragmentation. Also, OA (upto 5.0%) decreased the growth rate. XRD analysis confirms struvite crystallinity. Pure crystals and those grown with OA showed identical XRD pattern, indicating that the crystalline nature may be unaffected. For crystals with OA, FTIR spectrum shifted to higher wave numbers, implying that the various organic compounds in OA might be absorbed on the crystal surface. TG-DTA studies showed similar thermal behaviour for both pure crystals and those with OA. However, the later revealed lowerendothermic temperature, indicating lower thermal stability. Fragmentationand lower thermal stability of struviteindicatedthat OA was a potent inhibitor of struvite and could be effective for urinary stone treatment.