Eight weeks of daily supplementation with the extract led to improvements in the activity of immune-related white blood cells, including NK cells, according to data published in Medicine.
Researchers from Daejeon University in Korea also noted that there no adverse effects associated with the fungi extract supplements.
“The results of this clinical trial suggest that the oral administration of Phellinus linteus extract for 8 weeks is safe and may enhance performances of individual immune system,” they wrote.
As noted by Dr Mark Tallon, Managing Partner Legal Foods, in a recent article for NutraIngredients, recent analysis puts the global function mushroom category at $24.9bn, with a CAGR of 9.5% expected to reach $47.2bn by 2028 (Grand View Research, 2022).
“This growth can be put down to a few key categories that have continued to develop of the back of COVID and more recently the increasing stress due to inflation and other income pressures such as fuel / energy costs. These include immune health, stress, and sleep,” stated Dr Tallon.
The researchers noted that approval of Phellinus linteus (PL) as a raw material in functional supplements and medicines in Korea is hindered by the lack of precedent clinical trial using the fungi. They therefore conducted an appropriate trial using the lactate dehydrogenase cytotoxicity assay.
Ninety-eight 98 subjects were randomly assigned to consume either 1,000 mg of the Phellinus linteus mycelium extract per day or placebo for eight weeks.
The results showed that the activity of NK cells was significantly improved in the PL group, compared with placebo.
In addition, a range of other immune-related biomarkers were also improved, including TNF-alpha, IFN-gamma, IL-1beta, IL-2, IL-6, IL-12, and IgG1.
“These results suggest that the intake of PL mycelium extract improves the immune function of individuals. In addition, the safety evaluation, through adverse event recording, laboratory testing, and vital sign monitoring, confirmed that the PL extract is not associated with hepatotoxicity and renal toxicity,” wrote the researchers. “Therefore, the long-term consumption of PL extract is considered safe.
“In order to evaluate the therapeutic benefits of consuming the PL extract, further investigation should be carried out with patients with compromised immunity, in addition to the healthy individuals tested in this clinical trial.”
August 26, 2022 - Volume 101 - Issue 34 - p e30226, doi: 10.1097/MD.0000000000030226
“Effects of Phellinus linteus extract on immunity improvement: A CONSORT-randomized, double-blinded, placebo-controlled trial”
Authors: Y.H. Ku, et al.