Sign up for our daily Newsletter and stay up to date with all the latest news!

Subscribe I am already a subscriber

You are using software which is blocking our advertisements (adblocker).

As we provide the news for free, we are relying on revenues from our banners. So please disable your adblocker and reload the page to continue using this site.

Click here for a guide on disabling your adblocker.

Sign up for our daily Newsletter and stay up to date with all the latest news!

Subscribe I am already a subscriber
Utrecht University research

Residual waste from mushroom cultivation removes pollutants from water

Water can be purified using mushroom substrate: the mixture of fungal filaments and horse manure that remains after harvesting mushrooms. The substrate effectively decreases concentrations of pesticides and drugs in contaminated water. Utrecht University researchers Brigit van Brenk, Han Wösten, and colleagues demonstrate this in a paper in the scientific journal Applied Microbiology and Biotechnology. The results show the potential of the substrate as a promising alternative to current water purification methods.

White button mushrooms (Agaricus bisporus) are grown on composted, sterilized horse manure. Grains containing the fungus are mixed into the compost, from which fungal filaments grow that fill the compost. Fruiting bodies of the fungus, mushrooms, eventually develop from this network of filaments.

But what to do with the substrate after the mushrooms are harvested? In the Netherlands, not much is done with the leftover waste: instead, large quantities are sent to Germany to be used as fertilizer. But couldn't the substrate be put to better use?

Van Brenk and her colleagues suspected that there might be a better way to use the substrate. Fungi that live off dead plant material, such as white button mushrooms, make enzymes to break down lignin. However, these enzymes are not highly specific, and it has been shown that they also break down substances other than lignin.

The researchers therefore decided to investigate the potential of using the leftover waste from mushroom cultivation to purify contaminated water. After all, concentrations of drug residues, pesticides and other harmful substances in surface water and groundwater are increasing, posing a threat to aquatic life forms. Moreover, existing methods of purifying water of such substances are expensive.

Van Brenk: "When we take a medicine, a portion of it is excreted through our urine, eventually finding its way into sewage water. The biggest problem is that these substances are not properly removed from the water before it is discharged into rivers. And natural processes cannot break down these substances as rapidly as we introduce them, resulting in their accumulation in the water."

To test the efficiency of the mushroom substrate, the researchers first added eight substances to water, including DEET (an insect repellent), caffeine and carbamazepine, a drug used to treat epilepsy. Subsequently, the contaminated water was combined with fragments of the substrate. After two to seven days, the researchers examined whether the concentrations of the substances had changed. It was found that, depending on the substance, between 10 and 90 percent had been removed from the water. Van Brenk: "Existing, comparable methods for purifying water often target only one or two specific substances. Although the effectiveness of the substrate varies among different substances, these findings demonstrate its capability to remove a broad spectrum of substances from water. Other methods that offer such a wide range are usually quite expensive."


Publication date: