Powder Hydrolysates Research Articles

Conformation-Activity Mechanism of Alcalase Hydrolysis for Reducing In Vitro Allergenicity of Instant Soy Milk Powder.

Effective reduction of the allergenicity of instant soy milk powder (ISMP) is practically valuable for expanding its applications. This study optimized the enzymolysis technology of ISMP using single-factor experiments and response surface methodology, combined serological analysis, cellular immunological models, bioinformatics tools, and multiple spectroscopy techniques to investigate the effects of alcalase hydrolysis on allergenicity, spatial conformation, and linear epitopes of ISMP. Under the optimal process, special IgE and IgG1 binding abilities and allergenic activity to induce cell degranulation of alcalase-hydrolyzed ISMP were reduced by (64.72 ± 1.76)%, (56.79 ± 3.72)%, and (73.3 ± 1.19)%, respectively (P < 0.05). Moreover, the spatial conformation of instant soy milk powder hydrolysates (ISMPH) changed, including decreased surface hydrophobicity, a weaker peak of amide II band, lower contents of α-helix and β-sheet, and an enhanced content of random coil. Furthermore, the linear epitopes of major soy allergens, 9 from glycinin and 13 from β-conglycinin, could be directionally disrupted by alcalase hydrolysis. Overall, the structure-activity mechanism of alcalase hydrolysis to reduce ISMP allergenicity in vitro was preliminarily clarified. It provided a new research direction for the breakthrough in the desensitization of ISMP and a theoretical basis for revealing the potential mechanism of alcalase enzymolysis to reduce the allergenicity of ISMP.

Cu Promoted the Dynamic Evolution of Ni-Based Catalysts for Polyethylene Terephthalate Plastic Upcycling.

Upcycling plastic wastes into value-added chemicals is a promising approach to put end-of-life plastic wastes back into their ecocycle. As one of the polyesters that is used daily, polyethylene terephthalate (PET) plastic waste is employed here as the model substrate. Herein, a nickel (Ni)-based catalyst was prepared via electrochemically depositing copper (Cu) species on Ni foam (NiCu/NF). The NiCu/NF formed Cu/CuO and Ni/NiO/Ni(OH)2 core-shell structures before electrolysis and reconstructed into NiOOH and CuOOH/Cu(OH)2 active species during the ethylene glycol (EG) oxidation. After oxidation, the Cu and Ni species evolved into more reduced species. An indirect mechanism was identified as the main EG oxidation (EGOR) mechanism. In EGOR, NiCu60s/NF catalyst exhibited an optimal Faradaic efficiency (FE, 95.8%) and yield rate (0.70 mmol cm-2 h-1) for formate production. Also, over 80% FE of formate was achieved when a commercial PET plastic powder hydrolysate was applied. Furthermore, commercial PET plastic water bottle waste was employed as a substrate for electrocatalytic upcycling, and pure terephthalic acid (TPA) was recovered only after 1 h electrolysis. Lastly, density functional theory (DFT) calculation revealed that the key role of Cu was significantly reducing the Gibbs free-energy barrier (ΔG) of EGOR's rate-determining step (RDS), promoting catalysts' dynamic evolution, and facilitating the C-C bond cleavage.

Extraction, identification, and molecular mechanisms of α-glucosidase inhibitory peptides from defatted Antarctic krill (Euphausia superba) powder hydrolysates

The objective of this study was to explore the potential of Antarctic krill-derived peptides as α-glucosidase inhibitors for the treatment of type 2 diabetes. The enzymolysis conditions of α-glucosidase inhibitory peptides were optimized by response surface methodology (RSM), a statistical method that efficiently determines optimal conditions with a limited number of experiments. Gel chromatography and LC-MS/MS techniques were utilized to determine the molecular weight (Mw) distribution and sequences of the hydrolysates. The identification and analysis of the mechanism behind α-glucosidase inhibitory peptides were conducted through conventional and computer-assisted techniques. The binding affinities between peptides and α-glucosidase were further validated using BLI (biolayer interferometry) assay. The results revealed that hydrolysates generated by neutrase exhibited the highest α-glucosidase inhibition rate. Optimal conditions for hydrolysis were determined to be an enzyme concentration of 6 × 103 U/g, hydrolysis time of 5.4 h, and hydrolysis temperature of 45 °C. Four peptides (LPFQR, PSFD, PSFDF, VPFPR) with strong binding affinities to the active site of α-glucosidase, primarily through hydrogen bonding and hydrophobic interactions. This study highlights the prospective utility of Antarctic krill-derived peptides in curtailing α-glucosidase activity, offering a theoretical foundation for the development of novel α-glucosidase inhibitors and related functional foods to enhance diabetes management.

Dual Action of Reduced Allergenicity and Improved Memory of Instant Soybean Powder Hydrolysates.

Soy allergens are susceptible to inducing allergic reactions in infants and young animals, which have an impact on the effective daily utilization of proteins. In this study, we used Alcalase-hydrolyzed instant soybean powder (ISP) to clarify the sensitization changes of instant soybean powder hydrolysates (ISPH), and we explored the assisted memory-enhancing effects. BALB/c mice in the ISPH group showed significant improvement in the allergy symptoms, with their allergy symptom scores decreasing to (1.57 ± 0.53) and their specific serum IgE and IgG1 binding capacity decreasing by 28.00 and 25.73% (P < 0.05), which suppressed the mast cell degranulation rate. Meanwhile, the plasma HIS and IL-4 levels decreased by 12.59 and 25.32%, and the plasma INF-γ and IL- 10 levels increased by 30.64 and 27.79%, which obviously regulated the imbalance of Th1/Th2 cells and attenuated the tissue damage (P < 0.05). Furthermore, ISPH improved behavioral characteristics, increased cholinergic system activity, reduced neuronal cell damage or apoptosis, and increased the number of Nissl bodies to help improve memory in Kunming mice (P < 0.05). In general, alcalase-hydrolyzed ISP had the dual effects of reducing allergenicity and aiding in memory improvement.

Zinc Tolerance of Special Yeasts and Lactic Acid Bacteria for Use in the Food Industry

In order to address human zinc deficiency, fortifying staple foods with zinc is a safe and cost-effective solution. To ensure the nutritional properties and quality of a final product, zinc tolerance of the microorganisms involved in the fermentation is necessary. Bread, which is widely consumed, occupies a substantial place in many people’s diets, and is often based on a sourdough making process; thus, it might be an important headlining product. This study investigated the zinc tolerance of yeasts and lactic acid bacteria that are specifically suited to produce sourdough bread made with cricket powder hydrolysate and wheat flour. Amongst the yeasts, Kazachstania servazzii KAZ2 and Kazachstania unispora FM2 were only slightly affected in regard to cell growth and colony-forming ability when cultured in YPD broth spiked with 0.5 or 1 mM ZnSO4, respectively. Yarrowia lipolytica RO25 showed a higher tolerance for up to 2.5 mM zinc (ZnSO4). All the yeast strains were capable of accumulating zinc in the range between 200 and 400 fg/cell. The heterofermentative lactic acid bacterium Fructilactobacillus sanfranciscensis DG1 appeared to have a moderate zinc requirement and was homeostatically balanced, even under a high 20 mM extracellular ZnSO4 load. A better understanding of zinc homeostasis in yeast and lactic acid bacteria for food industry applications may lead to improvements in zinc fortification, which might contribute to diminishing Zn deficiencies, especially in vulnerable population groups.

Production of BCAA Fortified Soybean Powder Hydrolysate Using Enzymes from Bacillus amyloliquefaciens and Its Application in Functional Protein Formula Foods

Production of BCAA Fortified Soybean Powder Hydrolysate Using Enzymes from <i>Bacillus amyloliquefaciens</i> and Its Application in Functional Protein Formula Foods

Effect of spray-drying conditions on the physical and antioxidant properties of a hydrolysate from red tilapia (Oreochromis spp.) viscera

Fish hydrolysates have become one of the most remarkable sources of bioactive peptides. However, the processing conditions for incorporating hydrolysates into food matrices can affect their bioactive performance. The effect of temperature and pH on the radical scavenging activity of tilapia hydrolysate was determined in the wet hydrolysate. Also, a central composite design was used to study the effect of the drying conditions on moisture, drying ratio, productivity, drying rate, and antioxidant activity in the tilapia hydrolysate. The results showed that the hydrolysate has high activity at acidic and neutral pH; but at pH 10, the activity decreases significantly. In the spray-drying process, the antioxidant activity was higher at 115 °C. Moreover, inlet air temperature and feed flow had a statistically significant effect (p < 0.05) on response variables. High inlet air temperature and fast feed flow decrease the moisture of the powder hydrolysate and increase the drying rate and antioxidant activity. Scanning electron microscopy showed liquid bridges between particles with irregular concavities or pores on the surface and the presence of particle agglomerations due to the hygroscopicity of the hydrolysate.

Characterization of Peanut Protein Hydrolysate and Structural Identification of Umami-Enhancing Peptides.

Umami peptides are naturally found in various foods and have been proven to be essential components contributing to food taste. Defatted peanut powder hydrolysate produced by a multiprotease (Flavorzyme, Alcalase, and Protamex) was found to elicit an umami taste and umami-enhancing effect. The taste profiles, hydrolysis efficiency, amino acids, molecular weight distribution, Fourier transform infrared spectroscopy (FT-IR), and separation fractions obtained by ultrafiltration were evaluated. The results showed that peanut protein was extensively hydrolyzed to give mainly (up to 96.84%) free amino acids and peptides with low molecular weights (<1000 Da). Furthermore, β-sheets were the major secondary structure. Fractions of 1–3000 Da and <1000 Da prominently contributed to the umami taste and umami enhancement. To obtain umami-enhancing peptides, these two fractions were further purified by gel filtration chromatography, followed by sensory evaluation. These peptides were identified as ADSYRLP, DPLKY, EAFRVL, EFHNR, and SDLYVR by ultra-performance liquid chromatography (UPLC), and had estimated thresholds of 0.107, 0.164, 0.134, 0.148, and 0.132 mmol/L, respectively. According to the results of this work, defatted peanut powder hydrolysate had an umami taste and umami-enhancing effect, and is a potential excellent umami peptide precursor material for the food industry.

Unravelling the potential of cricket-based hydrolysed sourdough on the quality of an innovative bakery product

The purpose of this research was to evaluate the potential of a sourdough containing cricket powder hydrolysate by the RO25 Yarrowia lipolytica strain to produce an innovative bakery product. RO25 hydrolysed cricket bread (RO25H-CB) was compared with control bread obtained from a traditional sourdough using wheat flour and with an additional bread control obtained from no-hydrolysed cricket powder sourdough. The results obtained showed that RO25H-CB had a highest amount of proteins and free fatty acids than wheat control bread, attributed to the well-known proteolytic and lipolytic activities of Y. lipolytica. Moreover, RO25H-CB sample was characterised by high content of health-promoting and aroma precursors lipids as well as a lowest biogenic amine index among samples analysed, suggesting for this sample a high overall quality respect to no hydrolysed cricket powder bread. Finally, the data relating the sensory analysis highlighted good application opportunities for RO25 cricket hydrolysate as ingredients for baking. In fact, RO25H-CB had received positive evaluations for almost all the parameters considered. These results demonstrated that hydrolysates from Y. lipolytica, compared to the no hydrolysed cricket, were able to impart specific sensory and qualitative characteristics to the final product, with positive feedback from the involved panellists.

Bioconversion of Saw Dust Powder Acid Hydrolysis to Single Cell Protein by the Yeast Candida tropicalis

This study was aimed to grow the local isolates yeast Candida tropicalis on locally prepared sawdust powder hydrolysate as a basal medium and carbon source with respect to single cell protein (SCP) production. The saw dust powder was treated with 10% H2SO4 for one hour at 100 0C. After cooling the supernatant containing the isolated sugar separated from debris by filtration and used as a carbon source and basal medium for yeast growth and SCP production. A high amount of SCP was achieved after five days of incubation, the percentage of the produced SCP 39.05% of the biomass dry weight, which is equivalent to 3.07g/l. SCP formation biosynthesis was affected by the level of nitrogen present in the medium; a high amount of protein being achieved in fermentation medium containing 0.3% urea in which the percentage of the yielded SCP was increased to 42.54%, (3.71g/l) of the biomass dry weight. The effect of varying nitrogen sources on SCP accumulation was also assayed. Medium containing ammonium phosphate greatly stimulated protein production in which the produced SCP was increased to reach 5.90 g/l. The produced amount equivalent to (48.22%) of the biomass dry weight. Conversely, a medium containing sodium nitrate had a suppressive effect on SCP production. This evidence clearly suggests that the metabolic versatility of Candida tropicalis may be employed in the conversion of low-grade material into high SCP product.

Covalent and Ionic Bonding between Tannin and Collagen in Leather Making and Shrinking: A MALDI-ToF Study

Collagen powder hydrolysates were reacted with a solution of commercial mimosa bark tannin extract. The mixture was prepared at ambient temperature and prepared at 80°C to determine what reactions, if any, did occur between the collagen protein through its amino acids and the polyphenolic condensed tannin. The reaction products obtained were analyzed by matrix assisted laser desorption ionization time-of-flight (MALDI ToF) mass spectrometry. Reactions between the two materials did appear to occur, with the formation of a relatively small proportion of covalent and ionic linkages at ambient temperature but a considerable proportion of covalent linkages tannin-protein amino acids and the disappearance of ionic bonds. The linkages between the two materials appeared to be by amination of the phenolic –OHs of the tannin by the amino groups of the non-skeletal side chains of arginine, and by esterification by the –COOH groups of glutamic and aspartic acid of the aliphatic alcohol-OH on the C3 site of the flavonoid units heterocycle of the tannin. The proportion of covalent linkages increases markedly and predominate with increasing temperatures. This tightening of the tannin-protein covalent network formed may be an additional contributing factor both to leather wear resistance and performance as well to leather shrinking when this is subjected to excessive temperatures.

Potential of Yarrowia lipolytica and Debaryomyces hansenii strains to produce high quality food ingredients based on cricket powder

This research was aimed at producing, by the use of Yarrowia lipolytica and Debaryomyces hansenii strains, cricket powder hydrolysates endowed with high food safety, functionality, sensory and technological properties to be further used as food ingredients. The hydrolysates were characterised, in comparison to a control, by a reduced chitin content and higher contents of antimicrobial substances (acetic acid, short chain fatty acids, chitosan, and GABA) and health-promoting molecules (arachidonic and linolenic acids, GABA, AABA, and BABA). Additionally, in the cricket powder hydrolysates, a major release of free amino acids was detected, highlighting the high matrix digestibility. The hydrolysates obtained by the use of GRAS yeasts were characterised by the presence of many volatile molecules and specific amino acids typical of ripened and fermented foods that can impart good sensory properties. In this study, the ability of each tested strain, based on their physiological and metabolic features in the system taken into consideration, was shown to give rise to cricket-based hydrolysates characterised by specific physicochemical, sensory and functional fingerprints.

Valorisation of food waste via fungal hydrolysis and lactic acid fermentation with Lactobacillus casei Shirota

Food waste recycling via fungal hydrolysis and lactic acid (LA) fermentation has been investigated. Hydrolysates derived from mixed food waste and bakery waste were rich in glucose (80.0–100.2gL−1), fructose (7.6gL−1) and free amino nitrogen (947–1081mgL−1). In the fermentation with Lactobacillus casei Shirota, 94.0gL−1 and 82.6gL−1 of LA were produced with productivity of 2.61gL−1h−1 and 2.50gL−1h−1 for mixed food waste and bakery waste hydrolysate, respectively. The yield was 0.94gg−1 for both hydrolysates. Similar results were obtained using food waste powder hydrolysate, in which 90.1gL−1 of LA was produced with a yield and productivity of 0.92gg−1 and 2.50gL−1h−1. The results demonstrate the feasibility of an efficient bioconversion of food waste to LA and a decentralized approach of food waste recycling in urban area.

Utilização de enzimas proteolíticas para produção de hidrolisados proteicos a partir de carcaças de frango desossadas manualmente

Resumo O emprego de hidrolisados proteicos, oriundos de fontes animais e vegetais, em formulações específicas, é uma área de crescente interesse. O objetivo deste trabalho foi desenvolver diferentes hidrolisados liofilizados com alto valor proteico, obtidos a partir da hidrólise enzimática de carcaças de frango manualmente desossadas (CMD), um subproduto da indústria avícola, que normalmente é utilizado para a fabricação de carne mecanicamente separada (CMS). A matéria-prima utilizada foram carcaças de frango desossadas manualmente e congeladas (CMD), provenientes de animais abatidos com aproximadamente 42 dias de vida e com peso médio de 2,5 kg, adquiridas em um abatedouro da região sul do Brasil. Antes de serem processadas, foram descongeladas sob temperatura de refrigeração e cortadas em pedaços menores com faca de aço inox para facilitar sua homogeneização durante o tempo de hidrólise. Foram utilizadas três enzimas comerciais, Papaína®, Flavourzyme® e Protamex®. A hidrólise ocorreu em banho termostatizado com temperatura, tempo e pH controlados. Foi realizada a composição proximal da matéria-prima e dos hidrolisados liofilizados, atividade de água dos hidrolisados liofilizados e foram feitas as seguintes análises de controle da hidrólise: grau de hidrólise, teores de proteínas, sólidos totais, cinzas, caracterização de aminoácidos dos hidrolisados, rendimento, percentual de hidrólise e cor dos hidrolisados. Os resultados foram submetidos à análise de variância e teste de Tukey para comparação de médias. O grau de hidrólise maior foi com a Protamex, seguido da Papaína e da Flavourzyme. O teor de proteínas após os 120 minutos de hidrólise não variou estatisticamente (p&gt;0,05) entre a Papaína e a Flavourzyme. A composição de aminoácido demonstra que o hidrolisado obtido da Papaína possui uma composição mais próxima da recomendada pelos órgãos de controle. Concluiu-se que os hidrolisados proteicos obtidos da carcaça manualmente desossada (CMD) de frango apresentaram alto conteúdo proteico, caracterizando-se como matéria-prima promissora na formulação de dietas especiais.

Comparison of Antioxidant Activities of Hydrolysates of Domestic and Imported Skim Milk Powders Treated with Papain.

Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 αs1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods.

Utilização da carne mecanicamente separada de frango para a produção de hidrolisados proteicos a partir de diferentes enzimas proteolíticas

The use of hydrolyzed protein, derived from animal and vegetable sources, in specific formulations, is an area of growing interest. The aim of this study was to develop different powder hydrolysates with high protein value, from the enzymatic hydrolysis of mechanically deboned meat (MDM), a byproduct of the poultry industry, which can be a low-cost source for the production of these hydrolysates. The raw material used was frozen poultry mechanically deboned meat (MDM) purchased from an abattoir in southern Brazil, before use it was thawed under refrigeration and homogenized in a processor by 2 minutes. Three commercial enzymes were used, Papain, Protamex® and Flavourzyme®. The hydrolysis occurred in a thermostatized bath with temperature, time and pH controlled. Proximal composition of the raw material and lyophilized hydrolysates, control analysis such as hydrolysis degree of hydrolysis, protein, total solids, ash and amino acid characterization of the hydrolysates were performed. The results were evaluated by analysis of variance and Tukey’s averages test. The hydrolyzed obtained from the papain enzyme showed the best behavior, followed by Protamex and Flavourzyme. The hydrolysates from papain enzyme had higher protein content, soluble solids and lower ash content compared to other hydrolysates. The amino acid composition showed that the hydrolyzate from papain has a closer composition to what is recommended by the control organs. It was concluded that the protein hydrolysates obtained from mechanically deboned chicken had high protein content characterizing them as a promising raw material in the formulation of special diets.

Bioethanol production by a flocculent hybrid, CHFY0321 obtained by protoplast fusion between Saccharomyces cerevisiae and Saccharomyces bayanus

Abstract Fusion hybrid yeast, CHFY0321, was obtained by protoplast fusion between non-flocculent-high ethanol fermentative Saccharomyces cerevisiae CHY1011 and flocculent-low ethanol fermentative Saccharomyces bayanus KCCM12633. The hybrid yeast was used together with the parental strains to examine ethanol production in batch fermentation. Under the conditions tested, the fusion hybrid CHFY0321 flocculated to the highest degree and had the capacity to ferment well at pH 4.5 and 32 °C. Simultaneous saccharification and fermentation for ethanol production was carried out using a cassava (Manihot esculenta) powder hydrolysate medium containing 19.5% (w v−1) total sugar in a 5 l lab scale jar fermenter at 32 °C for 65 h with an agitation speed of 2 Hz. Under these conditions, CHFY0321 showed the highest flocculating ability and the best fermentation efficiency for ethanol production compared with those of the wild-type parent strains. CHFY0321 gave a final ethanol concentration of 89.8 ± 0.13 g l−1, a volumetric ethanol productivity of 1.38 ± 0.13 g l−1 h−1, and a theoretical yield of 94.2 ± 1.58%. These results suggest that CHFY0321 exhibited the fermentation characteristics of S. cerevisiae CHY1011 and the flocculent ability of S. bayanus KCCM12633. Therefore, the strong highly flocculent ethanol fermentative CHFY0321 has potential for improving biotechnological ethanol fermentation processes.

Butanol fermentation using wood powder hydrolysates produced by a modified supercritical water treatment

Butanol fermentation using wood powder hydrolysates produced by a modified supercritical water treatment

High quality biodiesel production from a microalga Chlorella protothecoides by heterotrophic growth in fermenters

The aim of the study was to obtain high quality biodiesel production from a microalga Chlorella protothecoids through the technology of transesterification. The technique of metabolic controlling through heterotrophic growth of C. protothecoides was applied, and the heterotrophic C. protothecoides contained the crude lipid content of 55.2%. To increase the biomass and reduce the cost of alga, corn powder hydrolysate instead of glucose was used as organic carbon source in heterotrophic culture medium in fermenters. The result showed that cell density significantly increased under the heterotrophic condition, and the highest cell concentration reached 15.5 g L(-1). Large amount of microalgal oil was efficiently extracted from the heterotrophic cells by using n-hexane, and then transmuted into biodiesel by acidic transesterification. The biodiesel was characterized by a high heating value of 41 MJ kg(-1), a density of 0.864 kg L(-1), and a viscosity of 5.2 x 10(-4) Pa s (at 40 degrees C). The method has great potential in the industrial production of liquid fuel from microalga.

Use of activated carbon for removing phenylalanine from reconstituted skim milk powder hydrolysates

With the aim of preparing dietary supplements for phenylketonurics, the activated carbon was used in this work to remove phenylalanine (Phe) from skim milk powder enzymatic hydrolysates. Six hydrolysates were prepared, using a protease from Aspergillus oryzae (AO), isolated or in association with papain (PA). Different conditions were tested for removing Phe, and the best one showed to be the use of a activated carbon:casein ratio of 118 (g) and a temperature of 25°C, which produced 96–99% of Phe removal. Among the hydrolytic conditions employed, the association of AO with PA (1h, 1g of enzyme/100g of substrate and 4h, 2g of enzyme/100g of substrate, respectively) led to the lowest absolute value for the final Phe concentration (0.060×10−4mg/100mg of protein).