Carotene Concentrates from Vegetable Leaf Wastes

Abstract

Certain vegetable leaf meals are rich sources of carotene, ranging in potency from 300 to 700 micrograms per gram.Petroleum ether solvents combine good solvent properties for carotene in leaf meals with relatively poor solvent properties for Other plant pigments. A number of procedures for the preparation of carotene concentrates from vegetable leaf meals have been devised. Most of them are hased on the rapid saponification of chlorophyll in petróleum ether solution, followed by adsorption treatment with hydrated lime. Upon removal of the solvent, deep red carotene concentrates equivalent to 20,000-200,000 I.U. vitamin A pier gram are obtained. The yield of purified carotene is from 85 to 95% of the carotene in the original extract.

Carotene Loss in Stored Leaf Meals and Extracts

“…CERTAIN dry vegetable leaf meals can be prepared which contain large amounts of carotene (6). These meals can be used as poultry feed supplements (IB) or as starting material for carotene concentrates (18). Since both the leaf meals and oil solutions of the carotene concentrate may often be held in storage for considerable periods, the carotene losses of these products under various storage conditions were investigated.…”

“…A carotene concentrate was prepared from a mixture of a number of leaf meals. The mixture was extracted with Skellysolve B; the extract was saponified to remove chlorophyll, and finally purified with hydrated lime according to the procedure of Wall, Kelley, and Willaman (18). Removal of the solvent gave the carotene concentrate used for all the "concentrate" experiments.…”

Concentrates of Fat-Soluble Constituents of Leaf Meal Extracts

“…and 1 to 10 microns pressure, a series of concentrates containing phytol, tocopherol, sterols, carotene, and xanthophyll is obtained. PREVIOUS publications from this laboratory have shown that properly prepared vegetable leaf meals (S) are excellent sources of carotene (IS), xanthophyll (15), chlorophyll (15), tocopherol (18), and sterols (14). In addition, vitamin K (8) and many other less well known compounds may be present.…”

“…In addition, vitamin K (8) and many other less well known compounds may be present. The conventional methods for isolating or concentrating any individual compound from leaves are usually so specific that many of the other products are destroyed or ignored (8,4,10,15). For more complete utilization of vegetable leaves, a method suitable for concentrating or partially separating a number of leaf Iipides is desirable.…”

“…The extracts thus obtained constituted the crude leaf lipide extract. The components of this mixture which were quantitatively studied and the references to the analytical methods used are as follows: carotene (IS), xanthophyll (15), tocopherol (13), and sterol (14). In addition, chlorophyll, phytol (derived from chlorophyll), and phospholipides were investigated to a limited extent.…”