Terpene-containing compositions and methods of making and using them

#The present invention relates to compositions comprising terpenes and hollow glucan particles or cell wall particles and methods for preparing such compositions. The compositions increase terpene stability and activity and provide a suitable carrier for the terpenes. The invention also relates to methods of using such compositions in the medical, veterinary and agricultural fields.

#Terpenes are chemical compounds that are widespread in nature, mainly in plants as constituents of essential oils. Their building block is the hydrocarbon isoprene (C5H8)n. Examples of terpenes include citral, pinene, nerol, b-ionone, geraniol, carvacrol, eugenol, carvone, terpeniol, anethole, camphor, menthol, limonene, nerolidol, farnesol, phytol, carotene (vitamin A1), squalene, thymol, tocotrienol, perillyl alcohol, borneol, myrcene, simene, carene, terpenene, and linalool.

#Terpenes are classified as Generally Recognized as Safe (GRAS) and have been used for many years in the flavouring and aroma industries. The LD50 in rats of citral is approximately 5 g/kg, which is a further indication of the relative safety of these compounds. Furthermore, terpenes have a relatively short life span of approximately 28 days once exposed to oxygen (e.g. air). Terpenes will decompose to CO2 and water. This decomposition or break down of terpenes demonstrates the safety and environmental friendliness of the compositions and methods of the invention.

#The present invention will now by further described with reference to the following, non-limiting, examples and figures in which:

#FIG. 1 represents a light micrograph of empty yeast cell walls;

#FIG. 2 represents a light micrograph of yeast cell walls encapsulating L-carvone;

#The following examples are provided to further enable those of ordinary skill in the art to make or perform the present invention. They are purely exemplary and are not intended to limit the scope of the invention. Unless indicated otherwise, parts are parts by volume or parts by weight, as indicated, temperature is in degrees Celsius (° C.) or is at ambient temperature, and pressure is at or near atmospheric. There are numerous variations and combinations of the compositions and conditions for making or using them, e.g., component concentrations, desired solvents, solvent mixtures, temperatures, pressures, and other ranges and conditions that can be used to optimise the results obtained from the described compositions and methods. Only reasonable and routine experimentation will be required to optimise these.

#The following protocol was performed to demonstrate that terpenes would load into yeast cell walls and other hollow glucan particles.

#Emulsions of citral and L-carvone were prepared by mixing 150 μl of the terpene with 100 μl of 10% Tween 80 in water and 250 μl of water.