Search Results (101)

In the artificial cultivation of Morchella sextelata (Black Morel), exogenous nutrient bags (ENBs) commonly employ wheat grains as the primary substrate raw material. However, this approach is costly and runs counter to the “non-grain” development direction advocated by the edible mushroom industry. Under controlled field conditions, twelve self-made formulations were set up and compared with a conventional market formulation to comprehensively analyze their impacts on the agronomic traits, yield, soil physicochemical properties, and economic benefits of M. sextelata fruiting bodies. The research findings indicate that the nutrient bag formulations have a significant effect on soil available nutrients. Specifically, the contents of alkali-hydrolysable nitrogen (AN) and available potassium (AK) exhibit a significantly negative correlation with M. sextelata yield (r = −0.60, p < 0.05; r = −0.72, p < 0.01, respectively). Among all the treatment groups, the KY1 formulation (comprising 30% wheat grains, 5% rice bran, 60% corncobs, 2% rice husks, 1% lime, and 1% gypsum) achieved the highest yield of 915.13 kg per 667 m², which was 16.1% higher than that of the control group. The net economic benefit per unit area (667 m²) reached CNY 75,282.15, representing a 20.7% increase compared to the traditional wheat grains-based formulation. In conclusion, partially substituting wheat grains with rice bran in ENBs can not only reduce reliance on staple food resources but also enhance yield and economic efficiency. Due to the differences in cultivated strains and environmental conditions, the impact on morel yield is substantial; therefore, the results of this study need further validation through pilot trials. Full article

Rhodotorula mucilaginosa plays a key role in developing the taste of dry-cured ham, while the mechanism of Rhodotorula mucilaginosa proteases on myofibrillar protein (MP) hydrolysis and the evolution of taste substances has not been studied. The enzymatic characteristics, hydrolysis capacities for MPs, free amino acid contents, metabolite compositions, and taste attributes were investigated during the interactions of MPs and proteases. The proteases of R. mucilaginosa EIODSF019 (RE) and R. mucilaginosa XZY63-3 (RX) showed high hydrolytic activities at the conditions of pH 5.0~7.0 and 30~40 °C. Compared with RX, RE showed a lower Michaelis constant (Km) value and a better affinity for protein substrates. RE showed a higher capability to degrade myosin and actin compared with RX and P. kudriavzevii XS-5 proteases (PK). The microtopography of enzyme-treated MPs in RE presented a smoother surface and lower root mean square roughness than that in RX and PK. The total content of free amino acids significantly increased from 0.34 mg/100 mL of CK to 17.10 mg/100 mL of RE after 4 h of hydrolysis of MPs. Sixty-two metabolites were identified by LC-MS/MS, and γ-glutamyl peptides were the main components of MP hydrolysates. Sensory scores of umami, richness, and aftertaste showed the largest values in RE among these groups. Partial least squares discriminant analysis and correlation network demonstrated that γ-Glu-Lys, γ-Glu-Tyr, γ-Glu-Glu, γ-Glu-His, γ-Glu-Leu, γ-Glu-Cys, γ-Glu-Ala, and γ-Glu-Gln were positively correlated with the improvements of umami, richness, and aftertaste in RE. Full article

Protein hydrolysates positively affect intestinal function in both humans and animals, but their impact on gut health and the gut microbial profile in cats has not been thoroughly investigated. In this study, a total of 30 adult cats were randomly assigned to one of three dietary treatments for a 60-day feeding trial. The three dietary treatments were as follows: (1) basal diet (CON), (2) diet containing 15% powdered chicken protein hydrolysate (HP15%), and (3) diet containing 15% liquid chicken protein hydrolysate (HL15%). Compared to the CON group, the HP15% group had a decreased calprotectin levels and fecal gases emissions (p < 0.05). A higher abundance of Bacteroidota, Veillonellaceae, and Bacteroidaceae, while a lower abundance of Firmicutes was showed in the HL15% group than that in the CON group (p < 0.05). At the genus level, compared with the CON group, an increased abundance of Bacteroides spp. and Bifidobacterium spp. was showed, whereas a reduced abundance of Alloprevotella spp. was presented in the HP15% and HL15% groups (p < 0.05). The metabolomic analysis revealed 1405 distinct metabolites between the HP15% and CON groups (p < 0.05, VIP-pred-OPLS-DA > 1), and the level of cholic acid decreased while the level of isodeoxycholic acid increased in the HP15% group (p < 0.05). The metabolomic analysis revealed 1910 distinct metabolites between the HL15% and CON groups (p < 0.05, VIP-pred-OPLS-DA > 1), and the levels of 4-coumaryl alcohol and enterolactone increased in the HL15% group (p < 0.05). In summary, this study suggested that partially replacing chicken meat with chicken protein hydrolysate in the diet of cats helps regulate the gut microbial community and metabolite profile and improves intestinal health. Full article

Partially substituting other proteins in soy-protein-based products is an effective method to meet nutritional and application requirements. However, the emulsifying properties of soybean protein isolates (SPI) when partially substituted with zein hydrolysates (ZH) remain unknown. In the present work, protein blend (0 h-SPI/ZH) from SPI and ZH with a ratio of 3.5: 1 (w/w) was treated by transglutaminase (TGase) for 0, 0.5, 1.0, and 1.5 h, respectively. SDS-PAGE analysis results indicate protein polymers were generated in SPI/ZH conjugates. Emulsifying activity of the conjugates (1.5 h-SPI/ZH) was significantly increased from 23.69 to 28.13 m² g⁻¹ in comparison with SPI, and there was no statistically significant difference (p < 0.05) in emulsion stability. The apparent viscosity, surface hydrophobicity of the SPI/ZH conjugates were significantly increased. Emulsion droplet size and zeta potential stabilized by 1.5 h-SPI/ZH were also increased; the values were 64.73 to 80.79 r.nm and −21.8 to −29.9 mV, respectively. CLSM results indicate that 1.5 h-SPI/ZH conjugates stabilized the emulsion and had a thicker adsorption layer. Overall, high values of negative zeta potential and suitable molecular weight distribution of the SPI/ZH conjugates might be responsible for the improved emulsifying property. This study provides insights for the preparation of soy-protein-based products as a promising food emulsifier. Full article

Background/Objectives: This study aimed to demonstrate the safety and suitability of an infant formula manufactured from partially hydrolysed whey protein (PHF) compared to standard formula manufactured from intact cow’s milk proteins (IPF; whey–casein ratio, 60:40) in healthy term infants. Methods: This multicentre, randomised, double-blinded, placebo-controlled trial included infants of mothers who intended to exclusively formula feed. Infants ≤ 28 days of age received PHF or IPF for at least 90 and up to 180 days. A group of exclusively breastfed infants was included for reference. The safety evaluation consisted of an equivalence analysis of weight gain within +/−3 g/d after 90 days, further growth parameters, and adverse events. Results: Of the 249 infants randomised, 143 (76 IPF; 67 PHF), as well as 45 breastfed infants, completed the study per protocol. The mean difference in daily weight gain between the formula groups was within the equivalence margins (−2.4 g/d (95% CI 0.3–4.5)) with estimated means (SEM) of 34.9 (0.78) g/d (IPF) and 32.5 (0.76) g/d (PHF). No significant differences in weight gain, length, and head circumference or in the number, severity, or type of adverse events were observed. Comparable growth patterns were observed in the breastfed group. Conclusions: The PHF is safe and supports adequate infant growth with a daily weight gain non-inferior to a standard IPF. Full article

A significant part of oil fields has reached a late stage of development, where technologies aimed at increasing the oil recovery factor are becoming particularly relevant. One such technology is surfactant–polymer flooding. To implement this technology, it is necessary to select a chemical formulation that retains its properties under reservoir conditions and enhances the efficiency of water flooding. This work presents a laboratory evaluation of various polymer and surfactant samples to develop an effective chemical formulation. The results demonstrate that anionic surfactants based on sodium laureth sulphate and betaine significantly reduce interfacial tension at the oil–water interface of the target reservoir. Furthermore, when combined with a partially hydrolysed polymer, the sodium laureth sulphate-based surfactant increases the capillary number by 4500 times (reducing interfacial tension from 32.77 mN/m to 0.065 mN/m and increasing the viscosity of the injected agent from 0.5 mPa·s to 4.36 mPa·s). Based on core flooding studies, it can be concluded that the proposed surfactant–polymer composition increases the oil displacement factor from the core sample by 0.15–0.24, depending on the injection volume. The selected formulation can be recommended for application in water flooding at the target reservoir. Full article

The powder obtained from rosehip waste can be used as an ingredient in meat products because it contains polyphenolic compounds with preservative and antioxidant effects and carotenoid compounds with a colouring effect. This study aimed to evaluate how partially replacing raw meat with this powder impacts the quality of pork sausages. Therefore, three sausage formulations (PSc-control pork sausages; PS2.7%rp-pork sausages with 2.7% powder from rosehip waste; PS5.5%rp-pork sausages with 5.5% powder from rosehip waste) were prepared and evaluated during storage from physicochemical, colour, texture, and sensory points of view, as well as for their polyphenol and carotenoid contents. The use of the powder from rosehip waste as an ingredient in pork sausages resulted in a significant decrease in moisture and protein content but an increase in total carbohydrates, polyphenols, and carotenoids; additionally, it significantly decreased the pH and easily hydrolysable nitrogen content of sausages, thus demonstrating a preservative effect. It also positively influenced their colour (by intensifying the shades of red and yellow), as well as the sausages’ gumminess and chewiness (by reducing them). Although it slightly affected their taste and texture, the consumer acceptance rate for reformulated sausages was reasonable. In conclusion, the powder obtained from rosehip waste is a promising functional ingredient in pork sausage reformulation. Full article

Carboxypeptidase is a Zn-dependent protease that specifically recognises and hydrolyses peptides with a hydrophobic side chain at the C-terminal residue. According to hydrolysis mechanisms proposed in the literature, catalysis requires a water molecule to be close to the Zn ion so as to be activated as a nucleophile. Among small molecules that resemble the slowly hydrolysed Gly-Tyr peptide, which have been previously designed as inhibitors and characterised structurally, a variant with the terminal amino acid in a D-configuration has been the most effective. Our molecular dynamics simulations of carboxypeptidase complexed with different variants of those inhibitor ligands as well as variants of the Gly-Tyr peptide show that the strength of the inhibitory effect is not related to the binding strength of the ligand. Our data rather support an earlier notion that the inhibition is, at least partially, due to blocking a coordination site at the Zn ion by the ligand coordinating the metal ion in a bidentate fashion. Full article

Green algae, particularly Ulva species, are rich in complex polysaccharides, such as ulvan, which have significant potential for biotechnological applications. However, the biochemical properties of ulvan depolymerised products remain underexplored. The enzymatic depolymerisation of ulvan has garnered attention owing to its cost advantages over alternative methods. Nevertheless, the biochemical characterisation of ulvan lyases, specifically those belonging to the polysaccharide lyase family 25 (PL25), is limited. In this study, we identified and biochemically characterised a novel PL25 ulvan lyase, PaUL25, which functions optimally at pH 10. Additionally, we explored the alpha (α)-glucosidase inhibitory properties of ulvan depolymerised products. PaUL25 exhibited optimum activity at 35 °C in Tris-HCl buffer (pH 10). Moreover, enzyme activity was enhanced by more than 150% in the presence of Mn²⁺ metal ions at and below concentrations of 10 mM. The endolytic action of PaUL25 produced ulvan oligosaccharides with degrees of polymerisation of 2 and 4 as its end products. Partially and completely hydrolysed ulvan oligosaccharides exhibited α-glucosidase inhibitory activity, with half inhibitory concentration IC₅₀ values of 3.21 ± 0.13 and 2.51 ± 0.19 mg/mL, respectively. These findings expand our understanding of PL25 and highlight the pharmaceutical potential of ulvan oligosaccharides, particularly as antidiabetic agents. Full article

Tenofovir disoproxil fumarate (TDF) is an antiretroviral drug extensively used by people living with HIV. The TDF molecule is hydrolysed in vivo and liberates tenofovir, the active part of the molecule. Tenofovir is a very stable drug and the discharge of its residues into the environment can potentially lead to risk for aquatic species. This study evaluated the TDF biodegradation and removal by cultures of Microcystis novacekii with the bacteria Pseudomonas pseudoalcaligenes. Concentrations of TDF of 12.5, 25.0, and 50.0 mg/L were used in this study. The process occurred in two stages. In the first 72 h, TDF was de-esterified, forming the tenofovir monoester intermediate by abiotic and enzymatic processes associated in an extracellular medium. In a second step, the monoester was removed from the culture medium by intracellular processes. The tenofovir or other by-products of TDF were not observed in the test conditions. At the end of the experiment, 88.7 to 94.1% of TDF and its monoester derivative were removed from the culture medium over 16 days. This process showed higher efficiency of TDF removal at the concentration of 25 mg/L. Tenofovir isoproxil monoester has partial antiviral activity and has shown to be persistent, maintaining a residual concentration after 16 days in the culture medium, therefore indicating the need to continue research on methods for total removal of this product from the aquatic environment. Full article

In addition to traditional use in fermented dairy products, S. thermophilus also exhibits anti-inflammatory properties both in live and heat-inactivated form. Recent studies have highlighted that some hydrolysates from surface proteins of S. thermophilus could be responsible partially for overall anti-inflammatory activity of this bacterium. It was hypothesized that anti-inflammatory activity could also be attributed to peptides resulting from the digestion of intracellular proteins of S. thermophilus. Therefore, total intracellular proteins (TIP) from two phenotypically different strains, LMD-9 and CNRZ-21N, were recovered by sonication followed by ammonium sulphate precipitation. The molecular masses of the TIP of both strains were very close to each other as observed by SDS-PAGE. The TIP were fractionated by size exclusion fast protein liquid chromatography to obtain a 3–10 kDa intracellular protein (IP) fraction, which was then hydrolysed with pancreatic enzyme preparation, Corolase PP. The hydrolysed IP fraction from each strain exhibited anti-inflammatory activity by modulating pro-inflammatory mediators, particularly IL-1β in LPS-stimulated THP-1 macrophages. However, a decrease in IL-8 secretion was only observed with hydrolysed IP fraction from CNRZ-21N, indicating that strain could be an important parameter in obtaining active hydrolysates. Results showed that peptides from the 3–10 kDa IP fraction of S. thermophilus could therefore be considered as postbiotics with potential beneficial effects on human health. Thus, it can be used as a promising bioactive ingredient for the development of functional foods to prevent low-grade inflammation. Full article

Cordycepin production in the submerged culture of Cordyceps militaris was demonstrated using hydrolyzed corn processing protein by-products, known as corn steep liquor hydrolysate (CSLH), as an alternative nitrogen source. The growth, metabolism, and cordycepin production of Cordyceps militaris were evaluated under various concentrations of CSLH induction. The results demonstrated that CSLH addition had positive effects on the growth and cordycepin production with various C. militaris strains. The optimum strain, C. militaris GDMCC5.270, was found to effectively utilize CSLH to promote mycelium growth and cordycepin production. Low concentrations of CSLH (1.5 g/L) in the fermentation broth resulted in 343.03 ± 15.94 mg/L cordycepin production, which was 4.83 times higher than that of the group without CSLH. This also enhanced the metabolism of sugar, amino acids, and nucleotides, leading to improved cordycepin biosynthesis. The increase in key amino acids, such as glutamic acid, alanine, and aspartic acid, in the corn steep liquor hydrolysate significantly enhanced cordycepin yield. The corn steep liquor hydrolysate was confirmed to be a cost-effective accelerator for mycelium growth and cordycepin accumulation in C. militaris, replacing partial peptone as a cheap nitrogen source. It serves as a suitable alternative for efficient cordycepin production at a low cost. Full article

The objective was to evaluate the effects of partial replacement of fish meal with protein hydrolysates and a commercial product in the diets of Penaeus vannamei post-larvae on zootechnical performance, proximate chemical composition, digestive enzyme activity, and total hemocyte count. The experiment was conducted in a clear water recirculation system comprising 24 experimental units, each with 30 shrimp with an average weight of 0.2 g. The treatments were control, chicken protein hydrolysate (CPH), enzymatic hydrolysate of chicken feathers, Aquabite^®, CPH + maltodextrin, and CPH + yeast, with four replicates each. The inclusion level of the different protein sources evaluated was 6%. At the end of the experiment, all shrimp were counted, weighed, and measured to determine the zootechnical performance. The body and feed chemical compositions, as well as the enzymatic activities of the hepatopancreas and the total hemocyte count in the hemolymph, were analyzed. The data obtained were subjected to ANOVA and Tukey’s test. There was no statistical difference between the treatments in any of the analyzed parameters. The results showed that all the evaluated protein hydrolysates can be used as partial substitutes for fish meal in P. vannamei diets during the nursery phase, maintaining equivalent and adequate digestive enzyme activities, health, growth, and body composition of the shrimp, in addition to being ecologically sustainable ingredients. Full article

This study evaluated the inclusion of protein hydrolysates and a commercial product as a partial replacement for fish meals in the diet of Pacific white shrimp (Penaeus vannamei) during the grow-out phase. A recirculation system with 24 experimental units and a biological filter was used. The experimental design was completely randomized with six treatments: control; chicken protein hydrolysate (CPH); enzymatic hydrolysate of chicken feathers; Aquabite^®; CPH + maltodextrin; CPH + yeast; and four replicates. After 50 days, the zootechnical performance and animal welfare parameters, centesimal carcass composition, digestive enzyme activity, and hemocyte count were evaluated. The treatments did not affect the zootechnical performance and total hemocyte count of the animals (p > 0.05). The evaluation of the antenna length indicated that all animals were in good health. The antenna length in treatment T5 was significantly greater (p > 0.05) than that in T4 and similar to that in treatments T3 and T6, demonstrating a positive influence of dietary protein hydrolysates. Concerning animal welfare, dietary protein hydrolysates influenced the length of the antenna (p < 0.05). The antenna length associated with different treatments indicated that the animals were in good welfare conditions in the production environment. With respect to body chemical composition, dry matter, ether extract, and ash were affected by the treatments (p < 0.05). Regarding the analysis of digestive enzymes, the treatments influenced the activities of amylase and trypsin (p < 0.05). The performance of the animals was satisfactory under all treatments, including enzymatic activity, demonstrating the possibility of using hydrolysates. Full article

Proteases are important enzymes because of their extended uses in several industries, such as food, beverages, pharmacy, detergents, and many others. Aspergillus is one of the most used fungi strains for enzyme production by solid-state fermentation (SSF). Disponibility of the carbon source is a key factor for protease production. In addition, the selection of solid support has great importance, as it must provide suitable airflow through the packed bed and nutrient diffusion inside the fermentable mass. Six Aspergillus strains and two inert supports (Agrolite (AL) and Polyurethane (PUF)) were tested for protease production from fish flour (FF) at different glucose concentrations (0, 5, 10, 15%) by SSF. The FF/PUF mixture at 70/30 (w/w) ratio, with 75.39% moisture, and a critical moisture point of 0.11 gH₂O/g, presented a texture that allowed heat and mass transfer and provided enough moisture to make free water available as required for microorganism growth during the fermentation process. Aspergillus oryzae 2095 produced higher amounts of neutral and alkaline proteases with the addition of 5% glucose to the growth medium. Kinetics studies reveal that protease production is partially associated with growth. The extracts obtained can be used in different industries, and especially to prepare fish high-value by-product hydrolysates. Full article