Anti-anxiety composition

Preparation of Free Form of Astaxanthin

[0041]Astaxanthin was extracted from Paracoccus carotinifaciens with the use of ethanol. Ethanol extraction was carried out in accordance with JP Patent Application No. 2007-222476 (JP Patent Publication (Kokai) No. 2009-50237 A) or JP Patent Application No. 2009-046105 (JP Patent Publication (Kokai) No. 2010-193865 A), which was filed by the applicant of the present invention in the past. The obtained astaxanthin was in the free form, and content thereof was 67% by weight. Also, it contained carotenoids, such as adonirubin (12 wt. %), adonixanthin (6 wt %), canthaxanthin (1 wt %), and asteroidenone (less than 1 wt %), in addition to astaxanthin.

[0042]In the following examples, the product obtained above was used as a carotenoid mixture comprising astaxanthin as a main ingredient (i.e., the free form of astaxanthin).

Evaluation of Anti-Anxiety Action of Free Form of Astaxanthin Via Elevated Plus-Maze Test

[0043]The anti-anxiety action of the free form of astaxanthin was evaluated using an apparatus for an elevated plus maze test in the following manner. As a comparative agent, a benzodiazepine anti-anxiety agent (diazepam) was used.

1-1. Experimentation Method

[0044]As experimental animals, 4-week-old ICR male mice (Japan SLC) were used. Mice were raised in separate cages under conditions in which they could freely ingest commercially available solid forms of feed and water. The conditions in the animal-raising chambers were designated as 12 hours in lightness and 12 hours in darkness (lightness: 8:00 a.m. to 8:00 p.m.), and temperature was set at 24° C.±2° C. All testing procedures were carried out from 10:00 a.m. to 6:00 p.m.

[0045]A carotenoid mixture comprising astaxanthin as a main ingredient was suspended in olive oil in an amount of 100 mg / kg-BW / day (per day per kg of mouse body weight) or 3

Evaluation of Anti-Anxiety Action of Free Form of Astaxanthin Via Hole-Board Test

[0054]The anti-anxiety action of the free form of astaxanthin was evaluated using an apparatus for a hole-board test in the following manner. As a comparative agent, a benzodiazepine anti-anxiety agent (diazepam) was used.

2-1. Experimentation Method

[0055]As experimental animals, 4-week-old ICR male mice (Japan SLC) were used. Mice were raised in separate cages under conditions in which they could freely ingest commercially available solid feed and water. The conditions in the animal-raising chambers were designated as 12 hours in lightness and 12 hours in darkness (lightness: 8:00 a.m. to 8:00 p.m.), and temperature was set at 24° C.±2° C. All testing procedures were carried out from 10:00 a.m. to 6:00 p.m.

[0056]A carotenoid mixture comprising astaxanthin as a main ingredient was suspended in olive oil in an amount of 100 mg / kg-BW / day or 300 mg / kg-BW / day of the free form of astaxanthin, and the res