Anti-norovirus and calicivirus effect of King Agaricus

We translated a conference presentation about anti-virus effect of King Agaricus in English.

Anti-calicivirus effect of Agaricus brasiliensis KA21

Background and Aim

Agaricus brasilensis KA21 strain cultivated outdoor in Brazil (=KA21), is reported to have adjuvant efficacy against cancer and tumours, hypoglycaemic action, and other effects. Previously, we reported an antiviral effect of agaricus against the influenza virus. The present study used feline calicivirus (FCV) and murine norovirus (MNV) as surrogates for norovirus to investigate the efficacy of agaricus against calicivirus.

Materials and method

A hot-water extract of dried and powdered fruiting bodies from KA21 grown outdoors was prepared and centrifuged. The remaining supernatant was then dialysed and used as AE. FCV and MNV were inoculated into both CRFK and RAW cells. Plaque assay and plaque size measurement were performed for each AE concentration. In addition, to clarify how the presence or absence of AE influences viral multiplication, viral load was measured in supernatant culture samples taken at 12, 24, 36 and 48 hours post-inoculation.

Results and discussion

When the sizes of the plaques formed by each virus at each AE concentration were measured, higher AE concentration was observed to correlate with reduced plaque size. Also, a viral multiplication assay found that, in comparison with a control, cultures including AE showed significantly reduced AE viral loads 24 hours after virus adsorption. In addition, when viral loads in virus-inoculated cells cultured in media including each AE concentration were measured, higher AE concentration was found to correlate with significantly lower viral load. These findings suggest that AE has a concentration-dependent antiviral effect on FCV and MNV.

This presentation was made at the 162nd meeting of the Japanese Society of Veterinary Science (at Tsukuba, Japan, 10th-12th, September, 2019.)

*We also published “anti-influenza virus effect of KA”.