Proteolytic Enzymes in Organic Media. I. The Selection of the Enzymes and the Optimization of the Aqueous-Organic Media for the Optically Active Aminoacids Syntheses by the Kinetic Resolution of their Esthers | Enzime proteolitice în mediu organic. I. Selectarea enzimei şi optimizarea mediului apos-organic pentru sinteze de aminoacizi optic activi prin rezoluţia cineticǎ a esterilor lor