Many botanical substances contain chemicals that have been found to be useful for the therapeutic treatment of various medical conditions. Since these chemicals are often present in very small amounts, techniques have been developed to extract these substances and to concentrate the therapeutically active agents. Various methods are available for extraction and purification of such substances, including the use of organic solvents, microwave systems, and supercritical CO2 extraction. Organic solvent-based extractions utilize added solvents that are evaporated to form a concentrated extract, which results in a damp, pasty mass that is typically further spray-dried onto a carrier for delivery. Alternatively, supercritical CO2 extraction is another method of collecting such extracts. This extraction method yields a thick, high viscosity resin, oil, or other fluid-like material that can have a honey-like consistency.
One pharmaceutically useful botanical substance is the extract of hops (Humulus lupulus L.). Hops cone flowers contain a variety of active agents, including alpha acids, iso-alpha acids, and beta acids, as well as a number of flavonoids and essential oils. Humulone, one of the alpha acids found in hops, has been demonstrated to suppress cyclooxygenase-2 activity, inhibit angiogenesis, and decrease bone loss. Some other biologically relevant properties of hops constituents include anti-inflammatory, antibacterial, antiviral, antifungal, estrogenic, anti-oxidant, anti-allergenic, anti-carcinogenic, and anti-proliferative properties.
As with other botanical substances, dried hops flowers contain very small amounts of alpha acids. Supercritical CO2 extraction and other solvent-based extractions of dried hops cones produce a thick, high-viscosity resin that can contain a high percentage of active hops constituents. While extraction is an effective means of providing alpha and beta acids in a highly concentrated form, the resulting extracts have very low solubility in water. This property can make digesting such extracts difficult, resulting in delayed absorption of the acids and delayed onset of certain therapeutic effects. It would therefore be useful to provide the primary constituents of hops extracts in formulations that are soluble in water. In addition, methods of making such formulations from hops extract resin would be desirable.