[Korea Farmers' News Agency, Reporter Lee Jang-hee] The Gyeonggi Agricultural Technology Institute revealed that the test results of cultivating Pleurotus ostreatus (oyster mushrooms) with a mixture of coffee grounds showed higher or equal yields compared to conventional substrates, indicating that it can achieve the effect of resource recycling and production cost reduction. Coffee grounds, which are the residue discarded after brewing coffee beans, can be used as a "substrate" for cultivating Pleurotus ostreatus. A "mushroom substrate" is an artificial culture medium used for growing mushrooms, primarily composed of organic materials such as sawdust, rice straw, and rice bran, mixed with water and nutritional supplements, then sterilized before use. Currently, the substrate materials used for mushroom cultivation in the country amount to approximately 1 million tons annually, of which about 600,000 tons