Potential target for mitigation of COVID-19 by food-derived bioactive peptides

Oral administration of food protein hydrolysate and naturally occurring peptides exert beneficial effects beyond conventional nutritional functions by supplying amino acids for protein synthesis. These peptides are referred to as food-derived bioactive peptides. The coronavirus disease 2019 (COVID-19) is caused by sever acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Some host and viral proteins are involved in the entry of SARS-CoV-2 into cells and their replication. Peptides with specific sequences can interact with these proteins and have potential prophylactic and therapeutic activities against COVID-19. However, it is difficult to deliver food-derived peptides to target organs without degradation by exopeptidases in the body. Alternatively, food-derived peptides and amino acid metabolites have been suggested to decrease risk factors of COVID-19 by modulating the renin-angiotensin system, the innate immune system, and the antioxidant system. This mini-review is based on in vivo responses to food-derived peptides and aims to introduce potential targets for these peptides in decreasing the risk and severity of COVID-19.

Blackberry phenolic and volatile extracts inhibit cytokine secretion in LPS-inflamed RAW264.7 cells

The anti-inflammatory activity of blackberries has been attributed to phenolic compounds, especially anthocyanins. The present study hypothesized that volatiles could contribute to anti-inflammatory activity as well. The anti-inflammatory properties of three blackberry genotypes varying in total volatile and phenolic contents were assessed by measuring concentrations of nitric oxide (NO), interleukin-6 (IL-6) and tumor necrosis factor -α (TNF-α) within LPS-inflamed RAW264.7 murine macrophage cells after a preventive treatment of either a phenolic or a volatile extract. Extracts from blackberry genotypes A2528T, A2587T and Natchez had total phenolic contents of 4315, 3369 and 3680 µg/mL, respectively, and total volatile contents of 283, 852 and 444 ng/mL, respectively. Phenolic and volatile extracts of all genotypes significantly lowered the secretion of NO, IL-6 and TNF-α in ranges varying between 20-42%, 34-60% and 28-73% inhibition, respectively. Volatile extracts exhibited greater anti-inflammatory properties than phenolic extracts, despite being present at much lower concentrations in the berries. Further research is needed to assess bioavailability and anti-inflammatory effect of blackberry volatiles in vivo.

Potential role of mushroom beta-glucans in immunity and inflammation in viral infections and COVID-19

According to the concept of trained immunity (TRIM), by stimulating the immune response with one pathogen, one can strengthen it against infection by another. With this understanding, one can take advantage of such immune responses with a stimulant such as β-glucan, which does not actually cause disease in humans, but has the advantage of generating primed immune cells that will respond to a variety of deadly infections. Mushroom β-glucans are known to act as training agents that leads to an increase in immune responses when these trained cells are subjected to a secondary stimulus. Understanding whether the TRIM processes are responsible for antiviral responses will undoubtedly provide a deeper understanding of other potential antiviral strategies, as the new SARS-CoV-2 is not the first- or last-time humanity has to deal with viral pandemics. More studies and clinical evidence are necessary for better understanding of the role of β-glucans in viral infections and COVID-19.

The prevention and treatment of Covid-19 and related development during pandemic

When the outbreak of human novel coronavirus was first reported in Wuhan, China at the end of 2019, the epidemic spread rapidly around the world and finally became a pandemic in 2020. In order to seek effective drugs to treat the Covid-19 infected patients for emergent use and for the disease prevention, researchers examined numerous existed antiviral drugs that may have the potential for Covid-19 treatment. At the same time, antibody treatment and vaccines development were ongoing simultaneously. The aim of this review is to introduce antibody therapy, vaccine development and potential antiviral treatments on Covid-19 and to discuss the future perspective on the Covid-19 pandemic.

Egg yolk phosphatidylcholine is more effective than soybean phosphatidylcholine in improving dyslipidemia of obesity in mice fed a high-fat diet

This study aimed to evaluate the effects of dietary egg yolk phosphatidylcholine (EPC) and soybean phosphatidylcholine (SPC) on obesity mice fed a high-fat diet (HFD). After 60 days of dietary intervention, the effects were evaluated by biochemical indices and serum lipidomic analysis. EPC and SPC markedly reduced serum total cholesterol, serum triacylglycerol (TAG) and low-density lipoprotein cholesterol, while increased high-density lipoprotein cholesterol. EPC was more effective in reducing malondialdehyde and superoxide dismutase in liver than SPC. Main lipids including glycerophospholipids, TAG, sphingolipids and fatty acyls were significantly modified by EPC. Compared with HFD, EPC increased 10 main differential lipids such as phosphatidyl ethanolamine (22:6_20:0). The expressions of related protein including sterol-regulatory element binding proteins sterol-regulatory element binding proteins (SREBP-1c) and peroxisome proliferator-activated receptor α (PPAR-α) were significantly down-regulated with EPC treatment. Therefore, EPC was more effective than SPC in improving obesity by regulating glycerophospholipid metabolism.

Potential of dietary supplementation with berries to enhance immunity in humans

One of the most prominent concerns that has arisen from global events such as the Coronavirus Disease 2019 (COVID-19) pandemic is how the immune system might be enhanced to provide greater protection against malignant conditions and diseases. Dietary modification is one of the major fields of research, with special focus on how diet interacts with immunity through impacts on factors such as the gut microbiome, inflammation, and nutritional imbalance. This review focuses on current research regarding the use of bioactives derived from berries as a dietary supplement to improve immunity, with discussions of relevant clinical studies. Major bioactive, metabolic compounds of focus- flavonoids, anthocyanins, alkaloids, dietary fiber, and stilbenes- have demonstrated biochemical merits in modulating immunity. In addition, blueberries, goji berries, black raspberries, and cranberries, which have been extensively researched and recently gained interest for their effects on the immune system in animal and cell models, may also hold promise in providing similar benefits to humans, though the precise immunological effects have yet to be clearly determined. Overall, the field of berry research as it relates to diet and immunity shows potential, but more clinical studies will be necessary for a full understanding of the mechanisms of berry immunomodulation.

The Power of Food Science and Technology and Nutrition for Sustainable Planet Health: Food Processing Saves Lives

Food processing includes a chain of events that starts in the farm and continues to the serving plate. These may include washing, dehydration, blanching, heat processing, and packaging, among others. While processing is essential for providing a safe food supply by eliminating harmful microorganisms and certain undesirable components, as well as revealing the desirable flavor of food, there has been much recent attempt to condemn food processing. Thus, loss of certain nutrients during processing and use of additives in ready to eat food as well as high levels of salt, sugar and fat/oil have been noted as being responsible for many non-communicable diseases due to increased incidence of obesity, diabetes and cardiovascular disease. These have all been categorised as ultra-processed food but attention to the definitions and details is most important.

Formulating a novel fermented soy milk functional meal replacement among overweight individuals: a preliminary weight loss clinical trial

Meal replacement is an optimising strategy in designing structured diets for weight management. In this study, a novel fermented soy-whey based beverage was fortified with dietary bioactive ingredients containing probiotic strains (Lactobacillus bulgaricus and Streptococcus thermophilus). The aim of this study was to evaluate its efficacy on the body weight loss of participants pre-and post-meal replacement. A total of 20 participants underwent the weight loss program. Over the 14-day trial, women volunteers had a body weight loss of 6.70% of their initial body weight, and men had a comparable body weight reduction of 6.18%. In comparison to the blood glucose baseline level of 3.5420 mmol/L, the meal replacement decreased the level of blood glucose by nearly 50%, reaching 1.7785 mmol/L. Total cholesterol level was reduced by the beverage with a 15.7% reduction. The functional drink also decreased the triglycerides and low-density lipoprotein significantly (p<0.001). A significantly higher level of high-density lipoprotein was obtained at Day 14 (1.73 mmol/L) compared with Day 0 (1.23 mmol/L). The meal replacement was able to provide satiety within the average of 180.7 minutes post-meal. This study supports the soy-based functional milk is of benefit for weight management, glucose homeostasis and blood cholesterol-lowering effect.

Antioxidant properties of camelina (Camelina sativa (L.) Crantz) protein hydrolysates

Camelina seed meal was used to produce protein hydrolysates using Alcalase and Flavourzyme. The hydrolysates were then fractionated by employing ultrafiltration membranes (3, 10 kDa). The antioxidant activities of camelina protein hydrolysates and peptide fractions were investigated. The essential amino acid content of camelina protein isolates and hydrolysates was comparable and adequate. All camelina hydrolysates exhibited the highest radical scavenging activity in both DPPH and ABTS assay compared to camelina protein isolates. When comparing the overall DPPH and ABTS radical scavenging activity of peptide fractions, smaller-size peptides (<3 kDa) displayed considerably higher values and hence more potency than larger-sized peptides (>3 kDa). Peptide fractions with 3-10 kDa had better metal chelation and reducing power than those < 3 kDa and > 10 kDa. These findings suggest that camelina protein hydrolysates could be employed as bioactive ingredients in the formulation of functional foods and against oxidative stress.

Protein hydrolysates from boarfish (Capros aper) and Atlantic salmon (Salmo salar) skin gelatin improve metabolic control in genetically obese diabetic (ob/ob) mice

There is increasing interest in dietary protein for management of Type 2 diabetes mellitus (T2DM) and obesity. The effects of twice-daily oral administration of a salmon skin gelatin hydrolysate (SSGH, 50 mg/kg), boarfish protein hydrolysate (BPH, (50 mg/kg), metformin (200 mg/kg), or saline control, were investigated in ob/ob mice. Non-fasting blood glucose was significantly reduced with SSGH (p<0.01), BPH (p<0.001) and metformin (p<0.001), which were reflected in reductions in glycated haemoglobin (HbA1c) (p<0.001, p<0.01 and p<0.01, respectively). Responses to oral and intraperitoneal glucose tolerance were improved (p<0.05-0.01), as well as circulating plasma lipid profiles (p<0.05-0.001). Chronic BPH treatment increased circulating plasma insulin (p<0.01), whereas SSGH improved insulin sensitivity (p<0.05), versus respective controls. All treatments significantly reduced energy intake (p<0.05-<0.001) versus (ob/ob) controls, without affecting overall bodyweight. These findings suggest that fish hydrolysates mediate potent anti-diabetic actions similar to metformin and might be suitable for the management and prevention of T2DM.