Effect of an Antisense Pectin Methylesterase Gene on the Chemistry of Pectin in Tomato (<i>Lycopersicon </i><i>esculentum</i>) Juice

Abstract

Pectins in tomato (Lycopersicon esculentum) juice processed from transgenic fruits with reduced levels of pectin methylesterase activity and from control fruits were characterized for total uronic acid, degree of methoxylation (DOM), and molecular mass. The molecular weights of pectins isolated from transgenic fruit juice are much higher than the molecular weights of pectins isolated from control fruit juice under all processing conditions. Depending on processing conditions, juice from transgenic fruits contained 30−50% higher amounts of total uronic acids and had 25−250% higher DOM compared to juice from control fruits. Keywords: Lycopersicon esculentum; tomato juice; pectin methylesterase; transgenic