Water soluble extract from a plant of the genus Solanum for use in the treatment of warts of the skin or mucosa of a human or animal subject, said water soluble extract comprises solamargina and solasonine, and said water soluble extract is obtained by the following steps: (a) subject a plant material of a plant of the genus Solanum to an extraction treatment by using an acidic aqueous solution with a pH value of 3∼5, so that a solution is obtained watery； (b) adjust the pH value of the aqueous solution obtained in step (a) to pH 8-10 with a base, such that a precipitate is formed； (c) washing the precipitate formed in step (b) with water, followed by drying, such that a dry product is obtained； (d) mixing the dry product obtained in step (c) with chloroform, followed by the addition of a suitable amount of a 100% alcohol, such that a mixture of chloroformoalcohol is formed； (e) mixing the chloroform-alcohol mixture formed in step (d) with a water / alcohol solution having a predetermined water: alcohol ratio, such that a mixture containing a chloroform-based layer and a layer that is not based on chloroform； (f) removing the chloroform-based layer from the mixture obtained in step (e), followed by the addition of an adequate amount of water； and (g) obtaining a supernatant from the mixture resulting from step (f), followed by drying the supernatant, wherein the resulting dry product is able to dissolve directly in water to form a clear and transparent yellowish aqueous solution.Extracto soluble en agua a partir de una planta del género Solanum para su uso en el tratamiento de verrugas de la piel o la mucosa de un sujeto humano o animal, dicho extracto soluble en agua comprende solamargina y solasonina, y dicho extracto soluble en agua se obtiene por las siguientes etapas: (a) someter un material vegetal de una planta del género Solanum a un tratamiento de extracción mediante el uso de una solución acuosa ácida con un valor de pH de 3∼5, de tal manera que se obtiene
