A method for the determination of methanol using alcohol oxidase is presented. The procedure offers the advantage over other photometric procedures that use potassium permanganate as the oxidant in that a subsequent reduction step is eliminated. The sensitivity of the assay is 1-20 Mg/mL of methanol. The procedure is rapid, selective, and versatile. The methyl ester content on a sample of pectin was determined from the methanol liberated upon its hydrolysis.

No abstract

The cloud pectin content of two commercial orange juice concentrates was 4.7 and 4.3%. The cloud pectin was solub&zed to varying deerees in 6% citric acid. oH 2.5: in 10M urea-6% citric acid, oH 2.5: iy hydrolysis of cloud-protein with protease; and in sodium bxalate; pH 4.5. Much of the urea-solubilized pectin reprecipitated upon dialysis. The binding of orange cloud to amino paramagnetic latex particles demonstrated a clear association of cloud pectin with cloud protein. Simulation of orange juice processing conditions indicated that some of the cloud pectin arises from the pulp during processing. About 60% of the cloud pectin is soluble pectin that has become associated with cloud protein, 2530% is calcium pectate and 15% is protopectin.

No abstract

Background: Although the biosynthetic pathways for anthocyanins and their regulation have been well studied, the mechanism of anthocyanin accumulation in the cell is still poorly understood. Different models have been proposed to explain the transport of anthocyanins from biosynthetic sites to the central vacuole, but cellular and subcellular information is still lacking for reconciliation of different lines of evidence in various anthocyanin sequestration studies. Here, we used light and electron microscopy to investigate the structures and the formation of anthocyanic vacuolar inclusions (AVIs) in lisianthus (Eustoma grandiflorum) petals.