Shiitake Mushroom Extract contains high amounts of beta-glucan (e.g. lentinan, ≥30% purity) and was also shown to increase natural killer cell (NK) activity by as much as 40% (250mg daily for 8 weeks) in clinical trials. Reduced risk of influenza infection by 32% (American Journal of Clinical Nutrition 2018 study). For example, the Japanese Ministry of Health, Labour and Welfare approved lentinan as an adjunct to chemotherapy, and when combined with stage III gastric cancer, the five-year survival rate increased from 11% to 29% (sample size 1,200 cases).
For cardiovascular health, eritadenine content in Shiitake Mushroom Extract (content ≥0.2%) reduced LDL cholesterol by 12% (500mg per day for 12 weeks) by inhibiting HMB-CoA reductase. Systolic blood pressure decreased by 7mmHg (Nutrition 2020 study). A pharmaceutical company developed a functional food with shiitake mushroom extract (100mg per tablet) with EFSA approval in the European Union, which caused a 9.5% average reduction in total cholesterol in consumers (3.2% reduction in the control group).
Antitumor activity is impressive. In vitro findings revealed that Shiitake Mushroom Extract (50μg/mL concentration) induced as much as 65% colon cancer cell apoptosis (via the Caspase-3 pathway), whereas when combined with 5-FU chemotherapy reduced drug resistance (IC50 value from 8μM to 2μM). In accordance with research by Seoul National University in South Korea, patients of breast cancer who were administered lentinan (1mg/kg/wk) adjuvant therapy had a rate of reduced tumor volume that was 28% higher in comparison with chemotherapy alone (P<0.05).
Excellent antioxidant capacity. Shiitake Mushroom Extract ORAC value (oxygen radical absorption capacity) is 15,000 μmol TE/g, three times greater than that of vitamin C (5,000 μmol TE/g), and can reduce the oxidative stress marker MDA (malonaldehyde) level by 34% (300mg per day, For 6 weeks). When a shiitake mushroom extract was added to one brand of exercise supplement, the exercise recovery time after exercise was reduced by 22% (using the CK enzyme activity test).
Safety data proves long-term intake. Shiitake Mushroom Extract once daily dose ≤1,500mg, the incidence of adverse reaction was as low as 1.2% (0.8% for the placebo), mostly temporary gastrointestinal distress. It has been recorded by the European Union Novel Food database as a food raw material, and there has not been one reported case of severe hepatotoxicity throughout 40 years of history in use in Japan (according to PMDA monitoring data).
Market application validates value. Us firm Host Defense’s Shiitake Mushroom Extract capsule retails $23 million a year (2022 data), and re-purchase rate by the customer is 78%. Chinese pharmaceutical firms have added it as an ingredient in the “anti-fatigue” health care product (Weifood health brand), and there is a 41% reduction in fatigue index (CFSI score) according to clinical trials.
Future research focuses on precision medicine. The scientists used AI to screen a novel polypeptide (<1kDa molecular weight) from Shiitake Mushroom Extract, which may inhibit novel coronavirus S protein binding (IC50=0.8μM in vitro), providing a novel direction for the discovery of antiviral drugs.