The phellinus linteus mushroom has indeed been approved both as
medicine and as a food product in Korea.
I have been able to find summaries/full texts of the following korean
6. Immunostimulating activity of Phillinus linteus extracts to
B-Iymphocyte Arch. Pharm. Res., 15(4), 379-381(1992) M. W. Han, G. T.
Oh, S. B. Han, H. M. Kim, and I. D. Yoo
7. Effect of Kp, an antitumor protein-polysaccharide from mycelial
culture of Phillinus linteus on the humoral immune response of
tumor-bearing ICR mice to sheep red blood cells Arch. Pharm. Res.,
16(4), 336-388(1993) M. W. Ham, K. S. Chung, S. S. Kim, H. S. Kim, K.
Y. Kim, and K. H. Kim
8. Phellinus linteus ?? ?????? ??? ????? Kp? ???? ????, 38(2),
158-165(1994) ???, ???, ???, ???, ???
9. Stimulation of humoral and cell mediated immunity by polysaccharide
from mushroom Phellinus linteus Int. J. Immunopharmac., 18(5),
295-303(1996) H. M. Kim, S. B. Han, G. T. Oh, Y. H. Kim, D. H. Hong,
N. D. Hong, and I. D. Yoo
10. The inhibitory effect of polysaccharide isolated from Phellinus
linteus on tumor growth and metastasis Immunopharmacology, 41,
157-164(1999) S. B. Han, C. W. Lee, Y. J. Jeon, .N. D. Hong, I. D.
Yoo, K. H. Yang, and H. M. Kim
List obtained from http://www.sangwhang.com/
In several conclusions, it is indicated that the effect that the
mushroom has on the human body is very effective for activating the
immune system but does not attribute to any side effects such as such
as bone marrow suppression, immunosuppression, hepatotoxicity and
renal toxicity. The studies indicate no danger towards long term
Also, the scientists and government of Democratic People's Republic of
Korea explicitly states on their official trade website "Sang-hwang
extracts in powder, capsule or liquid form when taken on a regular
basis, can significantly reduce the chances of getting cancer. There
are absolutely no known side effects of using Sang-hwang for long
periods of time."
If you would like any additional research about phellinus linteus
mushroom done in the Korean language, or would like clarification on
any part of the answer, please let me know.
Googe search terms: sang whang, and various combinations of korean
text using www.google.co.kr