Bones from beer residue

Waste from beer brewing could be recycled for use in an unexpected application – as a biomaterial for bone regeneration. Researchers in Spain have developed a biocompatible material which can be used as support for bone regeneration, and it comes from the bagasse – or residue from beer brewing. These materials could be an alternative to prosthesis made from processed sheep bones or synthetic materials, which are more expensive and harmful to the environment. Phosphorus, calcium, magnesium and silica – the main constituents of bone – are found in the bagasse, and once subjected to a modification process it can be used as a scaffold to promote bone regeneration for medical applications. Milagros Ramos from the Universidad Politécnica de Madrid explained the process: “Beer bagasses were first dried at 150°C for four hours in order to prevent putrefaction, due to their high humidity. Bagasse was then calcined at different temperatures, homogenised and their particle sizes controlled by sieving. The particulate powder is mixed with polyvinyl alcohol and this mixture is used to fill the polyurethane templates.” Analysis of the new material shows interconnected pores of between 50 and 500 microns in diameter – similar to the porosity of cancellous bone – which would enable complete vascularisation after the bone implant. [caption id="attachment_38777" align="alignright" width="200"] Mouse osteoblasts growing over 3D matrixes developed from food industry waste. Credit: Milagros Ramos and Ana Martínez Serrano, CTB-UPM.[/caption] The researchers used cell cultures to establish the biocompatibility of the materials by analysing the cell viability of cultured osteoblasts in the presence of powder materials components. After compacting and sintering, the materials formed 3D solid matrices and were analysed to see how well bone-like cells would adhere. Ramos said more work is needed to test the material to see how it integrates in the body. “Beer bagasse-derived materials will be tested in vivo first in rats and further in higher mammals. Preliminary results show no infections or inflammatory reactions, but we need to confirm in more detail the osseointegration of these new materials. Although preliminary in vivo experiments confirm the expectative created by the in vitro results, clinical trials are long-term processes, therefore the translation to the clinic is not contemplated within five years. These materials could be very attractive biomaterials for the enhancement of osseointegration of surgical prostheses and implants and for the purpose of tissue engineering bone.” The work was published in RSC Advances. Preparation, characterization and in vitro osteoblast growth of waste-derived biomaterials