Atlantic salmon (Salmo salar) waste as a unique source of biofunctional protein hydrolysates: Emerging productions, promising applications, and challenges mitigation.

The Atlantic salmon is an extremely popular fish for its nutritional value and unique taste among several fish species. Researchers are focusing on the utilization of Atlantic salmon waste for generating protein hydrolysates rich in peptides and amino acids and investigating their health benefits. Several technological approaches, including enzymatic, chemical, and the recently developed subcritical water hydrolysis, are currently used for the production of Atlantic salmon waste protein hydrolysates. Hydrolyzing various wastes, e.g., heads, bones, skin, viscera, and trimmings, possessing antioxidant, blood pressure regulatory, antidiabetic, and anti-inflammatory properties, resulting in applications in human foods and nutraceuticals, animal farming, pharmaceuticals, cell culture, and cosmetics industries. Furthermore, future applications, constraints several challenges associated with industrial hydrolysate production, including sensory, safety, and economic constraints, which could be overcome by suggested techno processing measures. Further studies are recommended for developing large-scale, commercially viable production methods, focusing on eradicating sensory constraints and facilitating large-scale application.

Effects of cottonseed meal protein hydrolysate on intestinal microbiota of yellow-feather broilers.

We evaluated the effects of cottonseed meal protein hydrolysate (CPH) on the intestinal microbiota of yellow-feather broilers. We randomly divided 240 chicks into four groups with six replicates: basal diet with 0% (CON), 1% (LCPH), 3% (MCPH), or 5% (HCPH) CPH. The test lasted 63 days and included days 1-21, 22-42, and 43-63 phases. The ACE, Chao1, and Shannon indices in the MCPH and HCPH groups of 42-day-old broilers were higher than those in the CON group (p < 0.05), indicating that the cecum microbial diversity and richness were higher in these groups. Firmicutes and Bacteroidetes were the dominant phyla; however, the main genera varied during the different periods. The abundance of Lactobacillus in CPH treatment groups of 21-day-old broilers was high (p < 0.05); in the 42-day-old broilers, the abundances of Barnesiella, Clostridia_vadinBB60_group, and Parasutterella in the LCPH group, Desulfovibrio, Lactobacillus, Clostridia_vadinBB60_group, and Butyricicoccus in the MCPH group, and Megamonas and Streptococcus in the HCPH group increased; in the 63-day-old broilers, the abundance of Clostridia_UCG-014 and Synergistes in the LCPH and HCPH group, respectively, increased (p < 0.05), and that of Alistipes in the LCPH and MCPH groups decreased (p < 0.05). And changes in the abundance of probiotics were beneficial to improve the intestinal morphology and growth performance. In addition, the LCPH treatment increased the complexity of the microbial network, while the MCPH treatment had the same effect in 42-day-old broilers. Thus, CPH increased the relative abundance of beneficial intestinal microbiota and enhanced the richness and diversity of the bacterial microbiota in broilers aged <42 days; this effect was weakened after 42 days.

From agricultural biomass to D form lactic acid in ton scale via strain engineering of Lactiplantibacillus pentosus.

Worsening environmental conditions make lactic acid a sustainable alternative to petroleum-based plastics. This study created a genetically-engineered strain Lactiplantibacillus pentosus PeL containing a disrupted L-lactate dehydrogenase gene to produce high yield and optically pure D-lactic acid. Cellobiose was identified as the optimal sugar in the single carbon source test, yielding the highest lactic acid. In 5-L fermentation tests, pretreated wood chips hydrolysate was the best lignocellulosic substrate for PeL, resulting in a D-lactic acid yield of 900.7 ±â€¯141.4 mg/g of consumed sugars with an optical purity of 99.8 ±â€¯0.0 %. Gradually scaled-up fermentations using this substrate were achieved in 100-, and 9,000-L fermenters; PeL produced remarkably high D-lactic acid yields of 836.3 ±â€¯11.9 and 915.9 ±â€¯4.4 mg/g of consumed sugars, with optical purities of 95.0 ±â€¯0.0 % and 93.8 ±â€¯0.2 %, respectively. This study is the pioneer in demonstrating economical and sustainable ton-scale production of D-lactic acid.

Sustainable Production of Shinorine from Agricultural Wastes Using Engineered Saccharomyces cerevisiae Expressing Novel d-Alanine-d-alanine Ligase from Pseudonocardia pini.

Shinorine, a compound known for its protective properties against UV radiation, is widely used in cosmetics and pharmaceuticals. Despite the construction of various recombinant Saccharomyces cerevisiae strains for shinorine production, achieving industrial-scale yields remains a challenge. In this study, genes encoding enzymes (DDGS, O-MT, and ATP-grasp enzyme) from Actinosynnema mirum were introduced into S. cerevisiae DXdT to enable the heterologous conversion of sedoheptulose 7-phosphate to mycosporine-glycine─the direct biosynthetic precursor of shinorine. Subsequently, a novel d-alanine-d-alanine ligase from Pseudonocardia pini was introduced to produce shinorine. The engineered strain (DXdT-MG-mi89-PP.ddl) produced 267.9 mg/L shinorine with a 48.6 mg/g dry cell weight (DCW) content in a medium supplemented with lignocellulosic hydrolysate derived from rice straw. Notably, the recombinant strain produced 1.7 g/L shinorine with a 79.1 mg/g DCW content from a corn steep liquor medium with a mixture of glucose and xylose. These results support the idea that sustainable shinorine production from agricultural wastes holds significant promise for industrial applications.

25SrRNA Methyltransferase CgBMT5 From Candida glycerinogenes Improves Tolerance and Fermentation Performance of Saccharomyces cerevisiae and Yarrowia lipolytica From Undetoxified Cellulose Hydrolysate.

The hydrolysis of cellulose generates inhibitors like acetate, suppressing fermentation performance. Here, 25SrRNA methyltransferase CgBMT5 from stress-tolerant yeast Candida glycerinogenes was used as an anti-stress gene element in Saccharomyces cerevisiae and Yarrowia lipolytica. Expression of CgBMT5 in S. cerevisiae increased cell tolerance to acetate, high osmolarity, and heat stress and rescued the delay in cell growth under acetate stress. Ethanol productivity was improved from 0.52 g·(L/h) to 0.69 g·(L/h). CgBMT5 improved GFP expression. The transcription factor ARG81 binds to the promoter of CgBMT5. CgBMT5 upregulated HOG1, GPD1, HAA1, and PMA1 and reduced ROS level, thereby improving cell resistance to acetate. CgBMT5 also improved resistance of Y. lipolytica Po1g to multiple-stress. The lipid titer was improved by 37% in the typical medium. Y. lipolytica-CgBMT5 produced 94 mg/L lipid in the undetoxified cellulose hydrolysate.

Deciphering the impact of stickwater hydrolysate on growth performance, immune response, and IGF-1/PI3K/AKT/mTOR signaling pathway in Siberian sturgeon (Acipenser baerii) fingerlings.

A feeding trial lasting 56 days was carried out to assess how the inclusion of stickwater hydrolysate (SWH) in the diet of Siberian sturgeon (Acipenser baerii) fingerlings affected their growth performance, immunity, digestive enzyme activity, and gene expression linked to the IGF-1/PI3K/AKT/mTOR signaling pathway. Siberian sturgeon fingerlings were acclimatized and fed isonitrogenous, isoenergetic diets with varying SWH concentrations (0%, 0.5%, 1.5%, and 2.5%). Growth parameters, serum proteins, immunological and digestive enzyme activities, and gene expression levels were assessed post-trial. Results demonstrated that 0.5%, and 1.5% SWH treatments significantly improved weight gain, specific growth rate, feed conversion ratio, and protein efficiency ratio. Notably, these diets also elevated serum protein and plasma globulin levels, reduced albumin-to-globulin ratios, and enhanced lysozyme, myeloperoxidase (MPO) activities, and immunoglobulin (Ig) M levels, indicating an immunostimulatory effect. Digestive enzyme activities were markedly increased in the SWH groups, particularly at 1.5%. Gene expression analyses revealed upregulation of mtorc1, s6K, akt, pi3k, and igf1, with concurrent downregulation of 4e-bp1 in the muscle of fish, signifying activation of the IGF-1/PI3K/AKT/mTOR pathway, which is central to protein synthesis and muscle growth. In conclusion, SWH at appropriate levels significantly enhances growth, digestive efficiency, and immune function in Siberian sturgeon fingerlings, while also activating key metabolic pathways.

Lymphatic absorption characteristics of eicosapentaenoic acid -enriched phosphoethanolamine plasmalogen and its gastric and intestinal hydrolysates.

The aim of this work was to study the lymphatic absorption characteristics of gastric hydrolysates and intestinal hydrolysates of eicosapentaenoic acid-enriched phosphoethanolamine plasmalogen (EPA-pPE) with focusing on the fate of EPA and vinyl ether bonds in the lymph fluid using lymphatic intubation and lipidomics. The results showed that the EPA peak occurred earlier in the gastric (1.5 h) and intestinal (1 h) hydrolysates than in the EPA-pPE group (3 h) with EPA peak content being 2.03 and 1.46 times higher, suggesting pre-hydrolysis contributed to lymphatic absorption. Further, duodenal injection of gastric hydrolysates sn2 EPA-lysoPE produced higher levels of EPA-LPC, PC, PE, and PG. Meanwhile, intestinal hydrolysates free EPA and sn1 lyso-pPE enriched the sn1 + 2 + 3 TG (20:5_20:5_20:5) and increased the vinyl ether bond-containing lipids, such as PE (18:0p_18:0) and PE (18:0p_20:4). This study provides insight into dietary molecular structures of EPA and plasmalogen.

Human Placenta Extract (HPH) Suppresses Inflammatory Responses in TNF-α/IFN-γ-Stimulated HaCaT Cells and a DNCB Atopic Dermatitis (AD)-Like Mouse Model.

Atopic dermatitis (AD), a chronic inflammatory disease, severely interferes with patient life. Human placenta extract (HPH; also known as human placenta hydrolysate) is a rich source of various bioactive substances and has widely been used to dampen inflammation, improve fatigue, exert anti-aging effects, and promote wound healing. However, information regarding HPH's incorporation in AD therapies is limited. Therefore, this study aimed to evaluate HPH's effective potential in treating AD using tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated human keratinocytes (HaCaT), immunized splenocytes, and a 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model. In TNF-α /IFN-γ-stimulated HaCaT cells, HPH markedly reduced the production of reactive oxygen species (ROS) and restored the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase 1(SOD1), catalase, and filaggrin (FLG). HPH reduced interleukin (IL)-6; thymus- and activation-regulated chemokine (TARC); thymic stromal lymphopoietin (TSLP); and regulated upon activation, normal T cell expressed and presumably secreted (RANTES) levels and inhibited nuclear factor kappa B phosphorylation. Additionally, HPH suppressed the T helper 2 (Th2) immune response in immunized splenocytes. In the AD-like mouse model, it significantly mitigated the DNCB-induced elevation in infiltrating mast cells and macrophages, epidermal thickness, and AD symptoms. HPH also reduced TSLP levels and prevented FLG downregulation. Furthermore, it decreased the expression levels of IL-4, IL-5, IL-13, TARC, RANTES, and immunoglobulin E (IgE) in serum and AD-like skin lesion. Overall, our findings demonstrate that HPH effectively inhibits AD development and is a potentially useful therapeutic agent for AD-like skin disease.

The Effect of the Species Source of Muscle and/or Digestive Enzymes on the Utilization of Fish Protein Hydrolysates as a Dietary Protein Source in First Feed for Larval Walleye (Sander vitreus).

Fish protein hydrolysates used in larval diets have been prepared from a variety of fish species, with different enzymes used to hydrolyze the protein. This study's objectives were to determine the effect of the dietary inclusion of fish muscle hydrolysates obtained from species-specific muscle/enzymes-versus hydrolysates produced from muscle/enzymes of a different species-on the growth performance, survival, skeletal development, intestinal peptide uptake, and muscle-free amino acid (FAA) composition of larval Walleye (Sander vitreus). Eight protein products were obtained for this study, comprising an unhydrolyzed and hydrolyzed product from each combination of muscle/enzymes from Walleye and Nile tilapia (Oreochromis niloticus). Four diets were produced, and the dietary protein was provided in a 50/50 ratio of unhydrolyzed and hydrolyzed protein from the respective muscle/enzyme combination. Four groups were fed one of the corresponding formulated diets, and two groups of larvae, fed a commercial starter diet and Artemia, respectively, served as reference groups. Larval Walleye fed the diet containing protein produced with the species-specific muscle and enzymes had a significantly higher weight after the study-30% higher than any other group. A significant interaction effect between muscle and enzyme sources on the growth of Walleye larvae was observed. The species-specific combination also led to a significant increase in postprandial FAA and indispensable amino acid concentrations in muscle. No significant differences were observed between the hydrolysate-fed groups in survival, deformity occurrence, or peptide uptake. Each hydrolysate-based diet significantly reduced skeletal deformities and survival compared to the commercial diet. The results of this study suggest that species-specific muscles and enzymes produce a more optimal dietary protein source for larval fish than non-species-specific products. Further research should focus on improving the physical properties of the formulated diets to reduce possible leaching of hydrolyzed protein and improve the survival of fish larvae.

Effects of vegetal protein hydrolysate application method, nitrogen level, and nitrate-to-ammonium ratio on growth and composition of hydroponic lettuce.

BACKGROUND: Vegetal-derived protein hydrolysates (PHs) have been recognized as sustainable biostimulant products due to their beneficial effects on crops. However, most studies on PHs have been conducted at a fixed ratio of nitrate-to-ammonium (NO3 -:NH4 +) without considering other N application scenarios, leading to inconsistent results among the studies. This study compared the influences of N levels (2 or 10 mM N), NO3:NH4 ratios (100:0, 75:25, 50:50, or 25:75), and PH application methods - control, foliar spray (PH-F) or root application (PH-R) - on the yield, morphology, nutrients, and nutraceutical quality of hydroponic lettuce. RESULTS: Nitrogen level, NO3:NH4 ratio, and PH application affected plant growth, morphology, and quality significantly, highlighting the importance of the interactions among these factors. Shoot growth was influenced by NO3:NH4 ratios, PH, and their interactions. Similar trends were observed in chlorophyll content. The interactions among all three factors significantly influenced root growth and morphology. Root application (PH-R) protected lettuce from yield loss caused by low NO3:NH4 ratios and from reduced antioxidant compounds caused by high N levels. Vegetal-derived protein hydrolysates improved nutrient uptake through two-way and three-way interactions although neither PH nor any interactions affected nitrate concentrations. CONCLUSION: This study demonstrated that PH interacts with N level and NO3:NH4 ratio, affecting hydroponic lettuce yield and quality. In particular, the root application of PH was the most effective method for enhancing yield (shoot fresh weight), quality (chlorophylls, carotenoids, flavonoids, and phenols), and nutrient uptake in hydroponically grown lettuce in relation to N form and level. © 2024 Society of Chemical Industry.

Neuroprotective effects of cerebroprotein hydrolysate and its combination with antioxidants against oxidative stress-induced HT22 cell death.

This study aimed to investigate the neuroprotective effects of cerebroprotein hydrolysate (CPH) against oxidative stress-induced HT22 cell death. Additionally, the effect of antioxidants such as quercetin (QC) and N-acetyl-L-cysteine (NAC) on the neuroprotective activity of CPH was evaluated. The mouse-derived hippocampal neuronal cell line HT22 was pretreated with CPH or a mixture of CPH and QC or NAC. HT22 cell death was induced by either 10 mM glutamate, 2.5 µM amyloid-ß (Aß)25-35, and 300 µM cobalt chloride (CoCl2). As results, CPH effectively alleviated HT22 cell death induced by glutamate, Aß25-35, and CoCl2. In addition, CPH combination with QC augmented cell viability in both glutamate- and Aß25-35-stressed conditions but had no synergic effect on the CoCl2-stressed condition. The synergic effect of CPH and NAC combination was observed under all cell death conditions. The neuroprotective actions of CPH and its combinations with QC or NAC against various oxidative stress-induced HT22 cell deaths were demonstrated, providing a promising strategy for developing CPH preparations for the prevention and/or treatment of neurodegenerative diseases such as Alzheimer's disease.

Characterization of a Bacterial Keratinolytic Protease for Effective Degradation of Chicken Feather Waste into Feather Protein Hydrolysates.

BACKGROUND: Chicken feathers contribute to large quantities of keratinaceous wastes that pose serious environmental problems and must be catered to properly. Chicken feathers are also a potential source of vital proteins, peptides, and amino acids, which could be used as low-cost animal feeds. Therefore, there has been increasing interest in keratinase-producing microbes for reprocessing and using keratinous biomaterials. METHODS: Among the five isolated keratinolytic microorganisms, one microbe, Bacillus XT 01, produced a significant amount of enzyme activity, which was partially characterized. The potential of this protease-producing microbe was investigated for converting feather keratin waste to valuable protein hydrolysate. RESULTS: Maximum keratinase production was observed after 5 days of incubating Bacillus XT 01 at an optimum temperature of 45 °C and pH 8.5. Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) and zymogram of ammonium sulfate precipitated culture supernatant showed the presence of several proteolytic enzymes with molecular weights between 30 and 60 kDa. The Bacillus strain caused almost complete feather degradation (98%) after 7 days of incubation at 45 °C in a shake culture medium. Antioxidant and reducing activities of the feather protein hydrolysate (FPH) elevated with increased cultivation time. Investigation of the effect of feather protein hydrolysate on plants indicated improved plant growth regarding the agronomic parameters, such as plant height, number of trifoliate leaves, number of pods, pod length, number of seeds per pod, and root length, which increased by 30.84%, 49.32%, 70.90%, 53.27%, 60.03%, and 54.71%, respectively. CONCLUSIONS: The prospective of Bacillus XT 01 for degrading feather waste keratin to highly valued hydrolyzed feather protein offers effectiveness in the poultry industry and ultimately decreases environmental pollution hazards.

Analgesic Effect of Human Placenta Hydrolysate on CFA-Induced Inflammatory Pain in Mice.

To evaluate the efficacy of human placenta hydrolysate (HPH) in a mice model of CFA-induced inflammatory pain. TNF-α, IL-1ß, and IL-6 are key pro-inflammatory cytokine factors for relieving inflammatory pain. Therefore, this study investigates whether HPH suppresses CFA-induced pain and attenuates the inflammatory process by regulating cytokines. In addition, the relationship between neuropathic pain and HPH was established by staining GFAP and Iba-1 in mice spinal cord tissues. This study was conducted for a total of day 28, and inflammatory pain was induced in mice by injecting CFA into the right paw at day 0 and day 14, respectively. 100 µL of 20% glucose and polydeoxyribonucleotide (PDRN) and 100, 200, and 300 µL of HPH were administered intraperitoneally twice a week. In the CFA-induced group, cold and mechanical allodynia and pro-inflammatory cytokine factors in the spinal cord and plantar tissue were significantly increased. The five groups of drugs evenly reduced pain and gene expression of inflammatory factors, and particularly excellent effects were confirmed in the HPH 200 and 300 groups. Meanwhile, the expression of GFAP and Iba-1 in the spinal cord was increased by CFA administration but decreased by HPH administration, which was confirmed to suppress damage to peripheral ganglia. The present study suggests that HPH attenuates CFA-induced inflammatory pain through inhibition of pro-inflammatory cytokine factors and protection of peripheral nerves.

Sustainable transforming toxic sludge into amino acids via bacteria-algae consortium.

The utilization of residual sludge by microalgae represents an environmentally sustainable method for resource recovery. In this study, Tetradesmus obliquus was cultured in hydrolysate derived from toxic sludge. Under symbiotic conditions with bacteria, Tetradesmus obliquus demonstrated enhanced toxin degradation capability and biomass accumulation, which exhibited a 1.39-fold increase in algal cell density, a 1.50-fold increase in Rubisco activity, and a total protein content of 341.83 ± 6.99 mg/L on the 30th day of cultivation. Metabolic utilization of substances in the hydrolysate by microalgae led to a toxicity removal rate of up to 60.43% by day 10. Phenylalanine showed the most significant increase among essential amino acids, and transcriptomic profiling identified genes (gene_16399, gene_16602) involved in phenylalanine enrichment. Macrotranscriptomics showed that bacteria upregulated the TCS system and tryptophan metabolism, supplying microalgae with more CO2 and IAA, which enhanced amino acid enrichment. This study established a non-toxic and biomass-accumulating bacterial-algal co-cultivation system.

Half substitution of mineral N with fish protein hydrolysate enhancing microbial residue C and N storage and climate benefits under high straw residue return.

The widespread utilization of straw return was a popular practice straw disposal for highly intensive agriculture in China, which has brought about some negative impacts such as less time for straw complete biodegradation, aggravation of greenhouse gas evolution, and lower efficient of carbon accumulation. It was urgent to find an eco-friendly N-rich organic fertilizer instead of mineral N as activator to solve the above problems and lead a carbon accumulation in long tern management. Besides, microbial necromass was considered as a crucial contributor to persistent soil carbon (C) and nitrogen (N) pool. How organic fertilizer activators influence microbial residue under different amount of crop residues input remained unclear. Thus, soils incorporating moderate and high rate of rice straw residue with additions of half and full of organic activators (fish protein hydrolysates vs. manure) were incubated for measuring carbon dioxide (CO2) and nitrous oxide (N2O) emission, microbial community and necromass. It was found that soil CO2 emission was rapidest during the first 13 days of straw decomposition but remained lowest in the treatments of 50% mineral N substituted by fish protein hydrolysate. There were that 81%-89% of total CO2 release and 59%-65% of total N2O emission occurred within 60 days of incubation period, and bacterial community and nitrate positively affected soil CO2 and N2O release respectively. Straw incorporation amount and organic activator application interactively influenced soil CO2 emission but not affected soil N2O emission. After 360 days of incubation, the difference of bacterial necromass was noticeable but fungal necromass remained almost unaltered across all treatments. All treatments showed generally comparable contribution of microbial necromass N to the total N pool. The treatment of 50% mineral N substituted by fish protein hydrolysate under high rate of straw input (HSF50) promoted the highest proportion of microbial necromass C in soil organic C because of alleviating N limitation for microorganisms. Finally, HSF50 was recommended as an eco-friendly strategy for enhancing microbial necromass C and N storage and climate benefits in agroecosystems.

Recovery of pure PET from wool/PET/elastane textile waste through step-wise enzymatic and chemical processing.

Textile waste is mostly incinerated because few recycling processes are available to recover valuable materials. In this work, a feasible chemo-enzymatic recycling process of wool/polyethylene terephthalate (PET)/elastane blends to recover pure PET is for the first time successfully demonstrated. Two novel enzyme formulations were selected for wool hydrolysis, whereas the recovered amino acids were quantified using high-performance liquid chromatography and two assays (Ninhydrin and Folin-Ciocalteu). Kinetic studies on the amino acid formation alongside reaction observations by scanning electron microscopy proved sufficient removal of wool within 8 hours with the new enzyme formulation, marking an acceleration compared to previous studies. Finally, elastane was separated with a non-hazardous solvent to obtain pure PET. Tensile tests on the recovered PET fibres reveal only slight changes through the enzymatic treatment and no changes induced by the applied solvent. The enzyme formulation was successfully tested on five different post-consumer wool/PET textile waste samples. This valorization approach enhances the circular economy concept for textile waste recycling.

Identification of New Angiotensin-Converting Enzyme Inhibitory Peptides Isolated from the Hydrolysate of the Venom of Nemopilema nomurai Jellyfish.

Recently, jellyfish venom has gained attention as a promising reservoir of pharmacologically active compounds, with potential applications in new drug development. In this investigation, novel peptides, isolated from the hydrolysates of Nemopilema nomurai jellyfish venom (NnV), demonstrate potent inhibitory activities against angiotensin-converting enzyme (ACE). Proteolytic enzymes-specifically, papain and protamex-were utilized for the hydrolysis under optimized enzymatic conditions, determined by assessing the degree of hydrolysis through the ninhydrin test. Comparative analyses revealed that papain treatment exhibited a notably higher degree of NnV hydrolysis compared to protamex treatment. ACE inhibitory activity was quantified using ACE kit-WST, indicating a substantial inhibitory effect of 76.31% for the papain-digested NnV crude hydrolysate, which was validated by captopril as a positive control. The separation of the NnV-hydrolysate using DEAE sepharose weak-anion-exchange chromatography revealed nine peaks under a 0-1 M NaCl stepwise gradient, with peak no. 3 displaying the highest ACE inhibition of 96%. The further purification of peak no. 3 through ODS-C18 column reverse-phase high-performance liquid chromatography resulted in five sub-peaks (3.1, 3.2, 3.3, 3.4, and 3.5), among which 3.2 exhibited the most significant inhibitory activity of 95.74%. The subsequent analysis of the active peak (3.2) using MALDI-TOF/MS identified two peptides with distinct molecular weights of 896.48 and 1227.651. The peptide sequence determined by MS/MS analysis revealed them as IVGRPLANG and IGDEPRHQYL. The docking studies of the two ACE-inhibitory peptides for ACE molecule demonstrated a binding affinity of -51.4 ± 2.5 and -62.3 ± 3.3 using the HADDOCK scoring function.

Improved skeletal muscle mass and strength through Protamex-mediated hydrolysis of perilla seed cake: Elevated rosmarinic acid levels as a contributing factor.

Perilla seed cake (PSC) is a byproduct of oil extraction from perilla seeds. It is rich in proteins and bioactive compounds. PSC was enzymatically hydrolyzed to form PSC hydrolysate (PSCH) to enhance the absorption of PSC, and their effects on muscle health in mice were compared. High performance liquid chromatography-tandem mass spectrometry analysis revealed that PSC contains several polyphenols, including rosmarinic acid (RA), caffeic acid, apigenin, and luteolin. The hydrolysate showed 1.44- and 7.04-fold increases in RA and caffeic acid contents, respectively, compared to those of PSC. The intake of PSC, PSCH, and RA significantly improved muscle mass and exercise performance in mice by upregulating protein synthesis, myogenic differentiation, oxidative muscle fiber formation, fatty acid oxidation, and mitochondrial biogenesis; however, PSCH had better promoting effects than PSC. In conclusion, PSCH improves muscle health through its bioactive compounds (particularly RA), indicating the potential of PSCH and RA in functional foods.

Novel umami-enhancing peptides of beef M. Semimembranosus hydrolysates and interactions with the T1R1/T1R3 taste receptor.

The taste mechanisms of beef umami and umami-enhancing peptides are not well understood. Therefore, novel umami and umami-enhancing peptides from beef M. semimembranosus hydrolysates were explored. Beef hydrolysates treated with Flavourzyme® showed an overall strong umami intensity compared to those treated with Alcalase®, papain, or Protamex®. The peptides were isolated via consecutive separation processes, and 31 potential umami peptides were identified. Molecular docking results showed that WGSEPIRIQ and TERGYSF had considerably low docking energies with the T1R1/T1R3 taste receptor through potential key binding sites for hydrogen bonding, including Ser48, Gly49, and Gln278 in T1R1, and Ser67, Asn68, and Arg247 in the T1R3 subunit. The taste of the identified peptides dissolved in ultrapure water was dominated by sourness. Instead, they demonstrated an umami-enhancing effect in the presence of monosodium glutamate. These results broaden our understanding of the taste mechanisms of beef umami-enhancing peptides and their potential applications as flavoring agents.

Fabrication of the W1/O/W2 emulsions loaded with Torreya grandis protein hydrolysate/polysaccharide complexes in the internal water: Characterization and stability.

In this study, the effect of Torreya grandis protein enzymatic hydrolysates (TGPH)/alginate dialdehyde (ADA) complexes in the internal aqueous phase on the physical stability of the water-in-oil-in-water (W1/O/W2) emulsions was studied. In the case of TGPH/ADA emulsions, the presence of ADA decreased the apparent viscosity of the emulsions and changed the flow behavior from shear thinning to Newtonian, leading to a decrease in volume-weighted average droplet diameter (D43) of the emulsions. Additionally, the emulsions at the TGPH/ADA ratios of 1:1 showed a lower turbiscan stability index (TSI) value, and smaller change in delta backscattering signal, compared to the emulsions. The enhanced pH stability and storage stability of the emulsions at the TGPH/ADA ratios of 1:1 was due to the formation of Schiff bases between TGPH and ADA. These results suggested that the covalent cross-linking of TGPH with ADA could significantly improve the stability of the emulsions, which provided an effective means for the development of new food-grade protein-polysaccharide complexes stabilized emulsions.