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Brewers' spent grain (BSG) protein rich fraction was previously hydrolysed using Alcalase (U) and three additional fractions were prepared by membrane fractionation; a 5-kDa retentate (U > 5), a 5-kDa permeate (U < 5) and a 3-kDa permeate (U < 3). In the present study, these fractions were added to milk, subjected to simulated gastrointestinal digestion (SGID) and their anti-inflammatory potential was investigated. The digestates caused a significant reduction (p < 0.05) in interleukin-6 (IL-6) production in Concanavalin-A (ConA)-stimulated Jurkat T cells. The samples did not significantly alter the production of IL-6 in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. IL-2 and interferon-γ (IFN-γ) production in stimulated Jurkat T cells and IL-1β and tumor necrosis factor-α (TNF-α) production in stimulated RAW 264.7 cells were not affected in the presence of the digestates. Results show that a SGID milk product supplemented with BSG hydrolysate and its associated ultrafiltered fractions can confer anti-inflammatory effects in Jurkat T cells.

Brewers' spent grain (BSG) is a major coproduct of the brewing industry and a potential valuable source of protein, cell wall polysaccharides, lignin, lipid, and phenolic compounds. The aim of this study was to assess the antioxidant potential of phenolic extracts isolated from BSG using cell wall degrading enzymes, Depol 740L, Shearzyme and, Ultraflo Max. The phenolic extracts were prepared from black BSG (derived from barley grains roasted at 200°C) and pale BSG (derived from malted barley grains). The phenolic extracts protected against hydrogen peroxide (H2O2)‐induced DNA single strand breaks in U937 cells as assessed using the comet assay. The extracts also protected against a H2O2 challenge in HepG2 cells, as assessed by measuring the cellular content of glutathione (GSH) and the activity of cellular antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT). Enzyme‐extracted black and pale BSG phenolic extracts protected against oxidant‐induced DNA damage and enhanced the cellular antioxidant activity in cells. Practical applications Enzyme‐extraction may be an effective alternative to conventional solvent extraction for the isolation of novel bioactive components, such as phenolics, from Brewers' spent grain. The BSG extracts may be used as a source of functional ingredients for the development of foods with potential benefits to human health.

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Protein hydrolysates from agricultural crops have shown encouraging bioactive and techno-functional characteristics that may be used in the development of functional foods (1) . It is important that bioactive protein hydrolysates demonstrate an ability to retain their bioactivity during digestion. Brewers' spent grain (BSG), a by-product of the brewing industry, is a potential source for the development of protein hydrolysates. The aim of this study was to incorporate a bioactive, BSG-derived protein hydrolysate into commercially available low-fat milk and assess the cytotoxicity and immunomodulatory effects of digestates, following in vitro gastrointestinal digestion.Hydrolysate U was obtained on Alcalase 2·4L digestion of a BSG protein-rich isolate. The hydrolysate was freeze-dried whole (U) or fractionated using 5 and 3 kDa molecular cut-off membranes, and permeates and retentate were designated U, U < 3, U < 5 and U > 5. Samples were added to low-fat milk at a concentration of 0·125% (v/v). A static gastrointestinal digestion model, as previously described (2) was used to mimic human digestion. The (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay was used to assess the effect of digestates (0-10% ; v/v) on Jurkat T cell proliferation. The effect of digestates on interferon-gamma (IFN-gamma) and interleukin-6 (IL-6) secretion in concanavalin-A (con-A) stimulated Jurkat T cells was measured by ELISA. Data were expressed as a percentage of untreated (control) cells.Treatment with digestates of milk with added hydrolysates U, U < 3 and U < 5 at 10% (v/v) and hydrolysates U > 5 at 5% and 10% (v/v), for 24 hours significantly reduced viability of Jurkat T cells. Following on from the cytotoxicity results, the highest non-toxic concentration of digestates (2·5%) was selected for further investigation. Preliminary results suggest that milk digestates with added >5 kDa hydrolysate can decrease IFN-gamma and IL-6 secretion in stimulated Jurkat T cells (data not shown). In conclusion, these results suggest that low-fat milk fortified with BSG hydrolysate can attenuate cytokine production in stimulated Jurkat T cells.

Brewers' spent grain (BSG) is the solid portion of barley malt which remains following wort production for the brewing industry. Black barley (roasted to 200°C) or pale barley (unroasted) is used for the brewing process, resulting in black or pale BSG (1) . BSG is a potentially useful source of phenolic acids following a published extraction procedure (2) . The alkaline-extracted phenolic acids have been shown to possess antioxidant activity (2) . The aim of this research was to determine antioxidant effects of BSG phenolic extracts following an enzymatic extraction process.The BSG extracts were derived from either dry or wet BSG and were either black (labelled A-F) or pale (labelled G-J). The 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was used to assess the effect of extracts on U937 cell proliferation at concentrations ranging from 0-20 % (v/v). The antioxidant effect of the extracts was measured by determining the DNA protective effects of the extracts in U937 cells exposed to H 2 O 2 , using the Comet assay.In general, pale BSG phenolic extracts (G-J) were less cytotoxic than black BSG extracts (A-F) (IC 50 values 0·06-7·01 % v/v) in U937 cells (data not shown). Preliminary results suggest that phenolic extracts can reduce H 2 O 2 -induced DNA damage in U937 cells. Previous research suggested that black BSG phenolic extracts had a greater DNA protective effect compared to pale BSG phenolic extracts (2) , however, results presented here demonstrated that there were no marked differences between black and pale extracts. This may be due to the lower concentration of black BSG phenolic extracts used in the present study (0·1 % v/v). In conclusion, these results suggest that phenolic extracts when prepared from BSG using enzymatic procedures possess good antioxidant activity in U937 cells.

Purpose Electromagnetic tracking (EMT) is beneficial in image-guided interventions to reduce the use of ionising radiation-based imaging techniques. Enabling wirelessly tracked sensors will increase the usability of these systems for catheter tracking and patient registration systems. This work introduces a novel method of wirelessly transmitting sensor data using a frequency modulation (FM) radio. Methods The proposed technique was tested using the open-source Anser EMT system. An electromagnetic sensor was connected in parallel to an FM transmitter prototype and wired directly to the Anser system for comparison. The performance of the FM transmitter was evaluated on a grid of 125 test points using an optical tracking system as a gold standard. Results An average position accuracy of 1.61 ± 0.68 mm and angular rotation accuracy of 0.04° for the FM transmitted sensor signal was obtained over a 30 cm × 30 cm × 30 cm volume, in comparison with the 1.14 ± 0.80 mm, 0.04° accuracy previously reported for the Anser system. The FM transmitted sensor signal had an average resolved position precision of 0.95 mm while the directly wired signal was found to have an average precision of 1.09 mm. A very low frequency ($$\sim $$ ∼ 5 mHz) oscillation in the wirelessly transmitted signal was observed and compensated for by performing a dynamic scaling of the magnetic field model used for solving the sensor pose. Conclusions We demonstrate that FM transmission of an electromagnetic sensor signal can be used to achieve similar tracking performance to a wired sensor. FM transmission for wireless EMT is a viable alternative to digital sampling and transmission over Bluetooth. Future work will create an integrated wireless sensor node using FM communication that is compatible with existing EMT systems.

Inflammation is an essential process in the body's reaction to nonlethal injury; however, excessive and uncontrolled inflammatory responses can lead to chronic diseases (1) . Several peptides derived from cereal sources including brewers' spent grain (BSG), a byproduct of the brewing industry, have demonstrated anti-inflammatory effects in vitro. Research from our laboratory has previously demonstrated that alkaline-extracted BSG protein hydrolysates possess anti-inflammatory activity in human Jurkat T cells (2) . The aim of this research was to investigate the ability of enzyme-extracted BSG protein hydrolysates to inhibit release of pro-inflammatory cytokines in stimulated macrophage and T lymphocyte cells.Ten enzyme-extracted BSG protein hydrolysates (A-J) were investigated. The effect of the BSG protein hydrolysates on cell proliferation was assessed using the MTT assay and non-toxic concentrations of 0·005 % (w/v) and 0·001 % (w/v) were selected for the investigation of cytokine production in conA-stimulated Jurkat T lymphocyte cells and LPS-stimulated RAW 264·7 macrophages, respectively. Cytokine production was measured by ELISA following a 24 hour incubation with BSG protein hydrolysates.BSG protein hydrolysates were more toxic in RAW 264·7 cells compared to Jurkat T cells, as determined by the MTT assay (data not shown). BSG protein hydrolysates A, H and J significantly (P < 0·05) decreased LPS-stimulated interleukin-6 (IL-6) production in RAW 264·7 cells. Hydrolysate A also significantly (P < 0·05) decreased tumor necrosis factor-α (TNF-α) production in LPS-stimulated RAW 264·7 cells, while hydrolysate J significantly (P < 0·05) inhibited IL-6 production in conA-stimulated Jurkat T cells. The results of this study suggest that selected enzyme-extracted BSG protein hydrolysates, particularly A and J, may be effective in reducing cytokine production in cells in culture and have potential to be developed as ingredients for functional foods aimed at combating chronic inflammation and related disorders such as atherosclerosis.