NOVELTY - Production of a target organic compound from glucose, galactose or their mixture, oligomer or polymer of glucose or galactose using a cell-free enzyme system, involves converting glucose and/or galactose to pyruvate as an intermediate product, involves (a) oxidizing glucose and/or galactose to gluconate and/or galactonate, (b) converting gluconate and/or galactonate to pyruvate and glyceraldehydes, (c) oxidizing glyceraldehyde to glycerate, (d) converting glycerate to pyruvate, and (e) converting pyruvate to the target compound.    USE - The process is useful for the production of a target organic compound chosen from ethanol, isobutanol, n-butanol and 2-butanol by a cell free enzyme system (claimed). The n-butanol is used in the synthesis of acrylate/methacrylate esters, glycol ethers, n-butyl acetate, amino resins and n-butyl amines, and as fuel in combustion engines. The 2-butanol is used as solvent for paints and coatings as well as food ingredients or in production of 1-buten. The isobutanol is used as solvent or as plasticizer or in production of isobutene.    ADVANTAGE - The process is performed without using ATP and/or ADP as cofactors and is highly efficient as it uses less number of enzymes and co-enzymes, cost-effective, and technically stable and produces target organic compound at high yield as the cell-free enzyme system is superior to cellular components, has reduced molecular complexity, rapid adaptability to harsh industrial reaction conditions and solvent tolerance and simplifies down-stream product recovery.    DETAILED DESCRIPTION - Production of a target organic compound from glucose, galactose or a mixture of glucose and galactose or a glucose-containing oligomer or polymer and/or a galactose-containing oligomer or polymer using a cell-free enzyme system for conversion of glucose and/or galactose to pyruvate as an intermediate product, involves (a) oxidizing glucose and/or galactose to gluconate and/or galactonate, (b) converting gluconate and/or galactonate to pyruvate and glyceraldehydes, (c) oxidizing of glyceraldehyde to glycerate, (d) converting glycerate to pyruvate, and (e) converting pyruvate from (b) and (d) to the target compound, where steps (a) and (c) are enzymatically catalyzed with one or more enzymes and the steps involve the use of the enzymes to reduce a single cofactor which is added and/or present for electron transport, and step (e) is an enzymatically catalyzed reaction involving the reduced form of the cofactor of steps (a) and (c), and the process is performed at 40 degrees C for 30 minutes.