Trehalose (CAS: 99-20-7)

Trehalose, also known as mycose or tremalose, is a natural alpha-linked disaccharide formed by an

α,α-1,1-glucoside bond between two α-glucose units. In 1832, H.A.L. Wiggers discovered trehalose

in an ergot of rye, and in 1859 Marcellin Berthelot isolated it from trehala manna, a substance made

by weevils, and named it trehalose.It can be synthesised by bacteria, fungi, plants, and invertebrate

animals. It is implicated in anhydrobiosis — the ability of plants and animals to withstand prolonged

periods of desiccation. It has high water retention capabilities, and is used in food and cosmetics. The

sugar is thought to form a gel phase as cells dehydrate, which prevents disruption of internal cell

organelles, by effectively splinting them in position. Rehydration then allows normal cellular activity

to be resumed without the major, lethal damage that would normally follow a dehydration/rehydration

cycle. Trehalose has the added advantage of being an antioxidant.

Extracting trehalose was once a difficult and costly process, but circa the year 2000, the Hayashibara

company (Okayama, Japan) confirmed an inexpensive extraction technology from starch for mass production.

Trehalose is currently being used for a broad spectrum of applications.

Structure

Trehalose is a disaccharide formed by a 1,1-glucoside bond between two α-glucose units. Because

trehalose is formed by the bonding of two reducing aldehyde groups, it has no capacity to participate

in the Maillard reaction. There is an industrial process where trehalose is derived from corn starch.

There are at least 3 biological pathways for trehalose biosynthesis.

Chemical properties

Trehalose is a nonreducing sugar formed from two glucose units joined by a 1-1 alpha bond, giving it

the name of α-D-glucopyranosyl-(1→1)-α-D-glucopyranoside. The bonding makes trehalose very

resistant to acid hydrolysis, and therefore is stable in solution at high temperatures, even under acidic

conditions. The bonding also keeps nonreducing sugars in closed-ring form, such that the aldehyde or

ketone end groups do not bind to the lysine or arginine residues of proteins (a process called glycation).

Trehalose is less soluble than sucrose, except at high temperatures (>80 °C). Trehalose forms a rhomboid

crystal as the dihydrate, and has 90% of the calorific content of sucrose in that form. Anhydrous forms of

trehalose readily regain moisture to form the dihydrate. Anhydrous forms of trehalose can show

interesting physical properties when heat-treated.