Caffeine fraction obtained from tea leaves and a method for inducing Agrobacterium tumefaciens-mediated genetic transformation in plants using said caffeine fraction

A thermolabile caffeine fraction produced by a method comprising:

• a. extracting dried tea leaves with about 10-40 weight % aqueous acetone to obtain an aqueous acetone fraction,
• b. extracting the aqueous acetone fraction of step (a) with n-hexane to obtain an aqueous layer and a lipid layer,
• c. extracting the aqueous layer with petroleum ether and ethyl acetate to remove catechins from the aqueous layer, and
• d. extracting the aqueous layer resulting from of step (c) with chloroform to obtain a chloroform fraction containing caffeine.