ISOLATION AND PURIFICATION OF QUEBRACHITOL FROM RUBBER FACTORY EFFLUENTS

Abstract

Sri Lanka has been producing about 70,OOO-90,OOOmetrtiocns of factory effluents annually inrubber plantations. Most of this is discharged into environment with out any prior treatment,causing serious environmental pollution problems in rubber growing areas. Use of rubberfactory effluents as a fertilizer for rubber and also for vegetable crops, has been investigated byseveral workers as an alternative to expensive treatment methods. Recovery of non-rubbersubstances of economic importance from rubber factory effluents, has also been attempted.

Quebrachitol is the chief water-soluble compound among sugars that are present in rubberfactory effluent. This non-rubber substance has a great demand in European countries due to itshigh pharmaceutical value. (as an antibiotic, anticancer drug etc) There are also several otherpotential applications related to quebrachitol, (i.e. in Iacquer industry for the preparation of theresin, as a chiral starting material for organic chemical syntheses). It has also been used as apharmacological research tool for the study of cell signaling mechanism and cellular responses.Since rubber serum is a waste product of the rubber industry and a good natural source forquebrachitol, isolation of quebrachitol from rubber factory effluent was attempted in this study.A column chromatographic method was adopted in this study to isolate quebrachitol from Heveaserum. Undiluted rubber serum obtained directly from the coagulating tank was used forisolation of quebrachitol. Rubber serum after conceitration by evaporation was deionized bycation (Amberiite IR 120, H+ form) and anion exchange (Dowex lx8, formate form) columnchromatography. Two methods were attempted for crystallization of quebrachitol fromconcentrated elute. Of them, alcohol precipitation method was found to be more efficient thancooling method. Precipitate was dissolved in water and recrystallized with ethanol. Employingthis method, 613.3mg of whitish quebrachitol crystals (m.p.193-1950C), were obtained fromone liter of rubber factory effluent

The development of a method to isolate quebrachitol from rubber factory effluent is of duelimport.ance (i.e. whilst yielding a substance of high commercial importance, it also eliminatesthe need for costly treatment). With the high market value of this substance, quebrachitol can bea good foreign exchange earner for Sri Lanka.