Circular bioeconomy in the bioproducts industry: Utilizing cocoa and coffee husk as inert supports for the production of Trichoderma koningiopsis (Tricotec® WP)

Abstract

The concept of circular bioeconomy has emerged as a sustainable strategy to addressing waste management, environmental degradation, and the demand for renewable resources. In the bioproducts industry, applying these principles enables the transformation of agricultural waste into valuable bio-based products. This study explores the potential of cocoa and coffee husks-bioproducts of the chocolate and coffee industries- as inert substrates for the production of Trichoderma koningiopsis - Th003, a beneficial fungus used in biocontrol and biofertilization. The research aims to assess the suitability of cocoa and coffee husks as growth substrates for T. koningiopsis – Th003. The husks underwent pre-treatment processes to remove contaminants and enhance their properties. Subsequently, T. koningiopsis- Th003 was inoculated on the treated husks and cultivated under controlled laboratory conditions. Fungal growth kinetics, biomass production, and viability were monitored throughout the process. The highest conidial concentration achieved was $1.12\times {10}^9$conidia/g in cocoa husks and $4.30\times {10}^8$conidia/g in coffee husks, comparable to the standard substrate (rice with wheat bran). Utilizing these agro-industrial waste materials as substrates for T. koningiopsis-Th003 let to production cost savings of up to 20 %. A second fermentation cycle with the waste materials yielded $2\times {10}^9$conidia/g in coffee husks, leading to savings of up to 50 %. These findings demonstrated the potential of coffee and cocoa husks as promising alternatives to cereal-based substrates for production active ingredients.