Photochemical and enzymatic synthesis of methanol from formaldehyde with alcohol dehydrogenase from Saccharomyces cerevisiae and water-soluble zinc porphyrin

We evaluated the photochemical and enzymatic synthesis of methanol from formaldehyde with alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae and NAD(+) photoreduction by the visible-light sensitization of zinc tetraphenylporphyrin tetrasulfonate (ZnTPPS) in the presence of methylviologen (MV2+), diaphorase, and triethanolamine (TECA). When the sample solution containing ZnTPPS, MV2+, NAD(+), diaphorase, and TEOA in potassium phosphate buffer solution was irradiated, the NADH produced increased with the irradiation time. After irradiation for 180 min, the conversion yield of NAD(+) to NADH was about 60% under 0.1 mM NAD(+) condition. The methanol production also depended on the conversion yield of NAD(+) to NADH. After irradiation for 180 min, 0.38 mu M of methanol was produced from formaldehyde (16 mu M). The conversion ratio of formaldehyde to methanol was about 2.3%. This result indicates that a system for the photochemical synthesis of methanol from formaldehyde was developed with ADH and the NADH produced by the photosensitization of ZnTPPS in water media. (c) 2006 Elsevier B.V. All rights reserved.