Higher Basidiomycetes mushrooms have been used in folk medicine throughout the world since ancient times. Edible higher Basidiomycetes are well known for their nutritional value and acceptability as well as their pharmacological properties. Mushrooms are a nutritionally functional food and a source of physiologically beneficial and noninvective medicines. 1) Various physiological properties (pharmacological effects) such as bioregulation (immunological enhancement), maintenance of homeostasis, regulation of biorhythm, cure of disease, prevention and improvement of diseases such as cancer, cerebral stroke, and heart disease are affected by mushrooms. It was also confirmed that mushrooms contain effective substances for decreasing serum cholesterol, improving hyperlipemia, antithrombotic effects, reduction of blood pressure, hypoglycemic action, and various other applications. 2) It was also found that the medicinal properties of cultured mycelia of Cordyceps sp. were as effective as those of the wild species.3) The typical Cordyceps used in traditional oriental medicine is Cordyceps sinensis which forms the fruiting body on the larvae of moths. C. sinensis is also known to have an effect on physiological systems: inhibition of the proliferation of human glomerular mesangial cells, 4) significant contribution to hypotensive activity, 5) and enhancement of Kupffer cell function. 6) However, since most of these physiologically active substances in various Cordyceps sp. were extracted from natural or solid cultured stromata, only a few active substances have been developed for pharmaceutical use. Recently, artificial media for high mass production have been developed in Korea to provide many opportunities for practical use. According to Koh et al.,7) the hot-water (HW) fraction of submerged cultured mycelia of C. sinensis stimulates the proliferation of bone marrow cells through Peyer's patch cells and has bioactivity.Therefore we studied the chemical components and the effects of the HW fraction, the most potent fraction in enhancing immune activity, against stimulus-induced fatigue and stress in vivo using rats and mice.
MATERIALS AND METHODSMicroorganism and Materials C. sinensis from Sanming Microbiological Institute in China was used in this experiment. The medium used for liquid culture contained the following per liter: 100 g of molasses, 1 g of yeast extract, and 3 g of K 2 HPO 4 . The submerged cultivation of C. sinensis was carried out at 150 rpm, 25°C, pH 5, and an airflow rate of 1.0 vvm for 7 d in a 5-l jar fermenter using liquid culture medium. The enzymatic kits to estimate the levels of cholesterol, aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), akaline phosphatase (ALP) were purchased from Sigma Chemical Co. (St. Louis, MO, U.S.A.).Animals Male ICR mice (6-8 weeks old) and SpragueDawley rats (6-8 weeks old) were purchased from DaihanBiolink Co. (Korea). Before adaptation, these animals were fed a commercial chow pellet diet (Samyang Co., Korea) containing the f...