Prolonged oxidative stress, induced by cellular metabolic processes and/ or environmental factors, can contribute to numerous chronic non-communicable diseases including neurodegenerative diseases, cancer, diabetes, liver injury, rheumatoid arthritis, respiratory disease, and accelerated ageing (1). This study investigated the cellular antioxidant activity of six blue whiting soluble protein hydrolysates (BWSPH, BW-SPH-A - BW-SPH-F), produced using a proprietary process, using RAW264.7 murine macrophage cells in culture. The antioxidant activity of the BWSPHs was determined via investigating their ability to scavenge the 1-diphenyl-2-picrylhydrazyl (DPPH) radical, as well as, to inhibit the production of reactive oxygen species (ROS) and to promote the expression of the endogenous antioxidant glutathione (GSH) and catalase (CAT) enzyme activity in oxidant-treated RAW264.7 cells. Statistical analysis was determined using ANOVA followed by Dunnett’s test (Prism 5.0, GraphPad Inc. San Diego, CA, USA). Results are expressed as the mean of at least three independent experiments ± SE. 
Hydrolysate BW-SPH-A exhibited superior DPPH radical scavenging activity compared to the other five hydrolysates, inhibiting DPPH by 50% at a concentration of 2.10 ± 0.12 mg/ mL. BW-SPH-A (0.5% w/v) was the only hydrolysate to significantly increase GSH and CAT levels in tert-butyl (tBOOH)- and hydrogen peroxide (H2O2)- challenged RAW264.7 cells, respectively, compared with the treated controls (p<0.05). Exposure of RAW264.7 cells to BW-SPH-A (0.5% w/v) for 24 h prior to treatment with H2O2 also significantly reduced (p<0.05) the generation of ROS compared to cells treated with H2O2 alone. 
The harsh conditions and oxidative nature of the gastrointestinal (GI) tract can alter the peptide profiles of the various BWSPHs and ultimately influence their antioxidant capacity. Simulated gastrointestinal digestion (SGID) of BWSPHs mimics this digestion process, thereby enhancing the physiological relevance of in vitro studies. For BWSPHs to have use as antioxidant agents, their digests must be able to transport across the intestinal barrier, eventually reaching the target cells and effectively stimulate endogenous antioxidant defence systems for the elimination of free radicals.  
The digest of hydrolysate BW-SPH-A (i.e., BW-SPH-A-GI) also increased GSH concentration in tBOOH-treated RAW264.7 cells and reduced ROS production in RAW264.7 cells challenged with H2O2 compared to treated controls (p<0.05). Additionally, the digest of BW-SPH-E (i.e., BW-SPH-E-GI) significantly increased CAT activity in H2O2-challenged RAW264.7 cells compared to the H2O2 control (p<0.05). It is possible that SGID of BW-SPH-E released antioxidant peptide(s) which were responsible for promoting CAT activity in oxidatively-stressed cells.
In conclusion, it is possible that hydrolysate BW-SPH-A, which exhibited antioxidant activity in vitro, may also protect against oxidative stress in vivo and thereby, may act as a safe and natural alternative to synthetic antioxidants. 

Reference: 
Droge, W (2002) Physiol. Rev 82, 47-95.

Antioxidant activity of blue whiting protein hydrolysates- an in vitro study

The gastrointestinal tract is amongst the most densely populated ecosystems on earth, home to an abundant and diverse collection of microbial species, not just bacteria but also Archaea, viruses, fungi etc. Significant interest in this area has been sparked in recent years by an appreciation of the importance of the gut microbiota in the health of the host, and this has led to the microbiome of humans and animals being investigated in depth. Studies have drawn links between host nutrition, the gut microbiota and metabolic and immune functions, which in consequence affect physiology.



The first investigations of the structure of the microbiota were culture-based, however the introduction of sequencing technologies such as Sanger sequencing and subsequent development of 454 sequencing and metagenomics approaches have become the mainstay of microbiota studies. The creation of reference databases and analysis software has provided invaluable tools for assigning taxonomy to generated data. Great progress in characterising the structure of the microbiome recently has paved the way for ongoing and future studies on the functional interactions between the microbiota and the host. Studies on the function of the microbiota are critical in understanding the role of the microbiota in human homeostasis and disease pathogenesis.



The conference will be presenting the latest advancements in gut microbiome and health research. It will bring together experts who are driving technological advancements and striving to understand how nutrition impacts gut microbiome and the interactions between gut microbiome and health.



[https://www.nutritionsociety.org/](https://www.nutritionsociety.org/)

[@NutritionSoc](https://twitter.com/NutritionSoc)

[Member-Connect](https://membership.nutritionsociety.org/signin?message=loginRequired&next=https://membership.nutritionsociety.org)

[Cambridge Core](https://www.cambridge.org/core/societies/nutrition-society)

Recordings of the conference will be available until 13 April 2021.