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Alkaline hydrolysis of chromium tanned leather wastes (CTLW) is a promising process that allows turning this waste into valuable materials, especially into protein, recovered as gelatin. Steam explosion, which is a fast, chemical‐free, and efficient process, was tested in this work as a pretreatment to open up the fibrous structure of CTLW and ease gelatin extraction through subsequent alkaline hydrolysis, increasing the process yield. Two steam explosion temperatures (130 °C and 150 °C) and residence times (5 and 15 min) were tested. The gelatin extracted in aqueous medium was characterized according to its dry mass content, ash content, viscosity, protein content, chromium content, and helix‐to‐coil transition temperature. CTLW steam exploded in more aggressive conditions (150 °C, 15 min) allowed the extraction of three times more protein when compared to CTLW without any pretreatment. However, samples treated at 150 °C produced lower‐quality (partially degraded) gelatin. Steam explosion performed at 130 °C for 15 min almost doubled protein extraction and resulted in a better quality gelatin. This is a promising process for the proper use of CTLW as raw material for the production of high added‐value products. © 2018 American Institute of Chemical Engineers Environ Prog, 38: 367–373, 2019

Diseases caused by infections are becoming harder to treat as the antibiotics used become less effective. A combination of strategies to develop active biomaterials that enhance antibacterial effects are desirable, especially ones that cause fewer side effects and promote healing properties. The combination of nanotechnology with substances that have intrinsic antibacterial activity can result in the advance of innovative biomedical materials. In this sense, the goal of this work is to provide a summary of natural rubber latex materials obtained from the Hevea brasiliensis tree loaded with metallic and metal oxide nanoparticles. These nanoparticles have unique size-dependent chemical and physical characteristic that make them appropriate for use in pharmaceutical and medical devices, while natural rubber latex is a natural and biocompatible polymer with an intrinsic antibacterial effect. Moreover, we outline here the origin, extraction methods, and composition of natural rubber latex and different techniques for the synthesis of nanoparticles, including physical, chemical, and biological approaches. Finally, we summarize, for the first time, the state of the art in obtaining natural rubber-based materials with metallic and metallic oxide nanoparticles for biomedical applications.