CHARACTERISATION OF ESSENTIAL OIL FROM LEAVES OF Euphorbia heterophylla AND ITS INSECT REPELLENT POTENTIAL

This study aimed at characterizing essential  oil  from leaves of  E.heterophylla and its insect repellent potential. Essential oil from fresh leaves of  E.heterophylla was extracted by  hydro distillation method, using a  Clevenger apparatus for 4 hours and the  yield was 0.1816%w/w. Repellence  test was conducted by  using 5 cockroaches in number which were  placed in a modified Y-tube Olfactometer and observations recorded for  each and every  odour introduced after 5 minutes in a relatively dark  room.  Repellency  activity  was computed  in percentage form and it  showed 100%. Analysis of  the chemical constituents of  the essential  oil  was done  by  Gas Chromatography coupled with a Mass Selective  Detector, Ethyl benzene(4.58%), p-Xylene (2.22%),o-Xylene(2.73%), Nonane(1.70%), Benzene,1-ethyl-3-methyl-(1.09%), Benzene  ,1,3,5trimethyl(1.09%),Decane  (0.82%), Limonene  (3.39%), Undecane  (0.44%),  3-cyclohexen-1-ol, 4methyl-1-(1-methylethyl)-(0.37%)  and Dodecane  (6.07%)  as the  constituents  of the  essential  oil from E.heterophylla leaves. All  these  chemical constituents are active  ingredients for insect repellants,  thus this essential oil can be  used a natural based insect repellant t  replace  the synthetic insect repellants.   

Key words:  Essential  oil,  Insect  repellent  potential,  Insect  repellant,  DEET,  GC-MS  and Euphorbia heterophylla.