Unveiling the hidden potential of hop extraction side streams: Chemical profiling and bioactivity

The processing of hops ( Humulus lupulus L. ) for the brewing industry generates side-products that vary depending on the applied extraction method [ 1 ]. These by-products are currently used – if at all – primarily as feed additives. However, the by-products still contain significant amounts of organic compounds. Due to the extensive industrial processing of hops, these by-products may contain rare or previously unidentified compounds in significant concentrations, which would likely go unnoticed or remain unrecovered by conventional whole-plant laboratory extraction techniques. In continuation of our studies on hop compounds [ 2 ], the objective of the study was to characterize a hop-derived side stream to evaluate the potential as a high-value by-product. The extracts were analyzed using LC-PDA-HRESIMS, GC-MS, and NMR. In addition, cellular protection assays were performed using HT1080 cell line to explore application potential in skin care and SH-SY5Y cells to assess potential neuroprotective effects. The fractions contained a substantial amount of multifidols, humulones, lupulones, flavonoids, and prenylated flavonoids, dependent on fractionation. This hop by-product thus represents a promising and previously underutilized source of rare bioactive compounds, offering new perspectives and value-added applications in the pharmaceutical or nutraceutical industry. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany