Enzymatic Treatment Research Articles

Do Media Extracellular Vesicles and Extracellular Vesicles Bound to the Extracellular Matrix Represent Distinct Types of Vesicles?

Mineralization-competent cells, including hypertrophic chondrocytes, mature osteoblasts, and osteogenic-differentiated smooth muscle cells secrete media extracellular vesicles (media vesicles) and extracellular vesicles bound to the extracellular matrix (matrix vesicles). Media vesicles are purified directly from the extracellular medium. On the other hand, matrix vesicles are purified after discarding the extracellular medium and subjecting the cells embedded in the extracellular matrix or bone or cartilage tissues to an enzymatic treatment. Several pieces of experimental evidence indicated that matrix vesicles and media vesicles isolated from the same types of mineralizing cells have distinct lipid and protein composition as well as functions. These findings support the view that matrix vesicles and media vesicles released by mineralizing cells have different functions in mineralized tissues due to their location, which is anchored to the extracellular matrix versus free-floating.

Effect of direct enzyme addition on the anaerobic digestion of OFMSW

The organic fraction of municipal solid waste (OFMSW) has high biodegradability and is a good feedstock for anaerobic digestion (AD). However, the solubilization of OFMSW is a limiting factor for AD. In this study, enzyme treatment was investigated to increase the conversion of complex materials of OFMSW into soluble fractions. Six different concentrations (0.15, 0.3, 0.5, 1.0, 1.5 and 3.0 mg/VSadded) of the alpha amylase enzyme (obtained from Aspergillus oryzae) were directly added as a powder and automated biochemical methane potential (BMP) tests were performed under thermophilic conditions. According to BMP tests, the methane (CH4) yield increased up to 17.5 % and the lag phase decreased to 19.3 % after enzyme addition. The highest CH4 yield and shortest lag phase were obtained when 0.5 mg of enzyme/VSadded was added to the reactor. These findings suggest that direct alpha amylase enzyme application obtained from Aspergillus oryzae can be used to increase biogas production by enhancing solubilization of OFMSW for AD.

Enzyme-treated red rice (Oryza sativa L.) bran extracts mitigate inflammatory markers in RAW 264.7 macrophage cells and exhibit anti-inflammatory efficacy greater/comparable to ferulic acid, catechin, γ-tocopherol, and γ-oryzanol

Ethnopharmacological relevanceRice (Oryza sativa L.), a staple food for a significant portion of the global population, has been recognized for its traditional medicinal properties for centuries. Rice bran, a by-product of rice milling, contains many bioactive compounds with potential pharmaceutical and therapeutic benefits. In recent years, research has highlighted the anti-inflammatory potential of rice bran, contributed by the bioactive components concentrated in their bran but, unfortunately, entrapped in the bran matrix, with limited bioavailability. Previous studies have reported that the enzymatic treatment of rice bran improves the bran's bioactive compound profile but did not investigate its impact on chronic conditions such as inflammation. Aim of the studyThis study investigates the anti-inflammatory effects of endo-1,4-β-xylanase (ERB) and Viscozyme (VRB) treated red rice bran extracts against lipopolysaccharide-induced inflammation in RAW264.7 macrophages in comparison with non-enzyme-treated bran (CRB). Further established their efficacy with known anti-inflammatory compounds-ferulic acid (FA), catechin (CAT), γ-tocopherol (GTP), and γ-oryzanol (ORZ). Materials and methodsThe RAW 264.7 macrophage cells were pre-treated with non-toxic concentrations (10–200 μg/mL) of FA, CAT, GTP, ORZ, CRB, ERB, and VRB, followed by inflammatory stimulation with LPS for 24 h. Further, the cell supernatant and pellets were harvested to study the anti-inflammatory effects by evaluating and measuring their efficacy in inhibiting pro-inflammatory cytokines (TNF-α, IL-6, IL-10, IL-1β) and mediators (ROS, NO, PGE2, COX2, iNOS) through biochemical, ELISA, and mRNA expression studies. ResultsThe findings showed that both ERB and VRB effectively inhibited the production of pro-inflammatory markers (TNF-α, IL-6) and mediators (ROS, NO, PGE2) by downregulating mRNA expressions of inflammatory genes (TNF-α, IL-1β, IL-6, IL-10, COX2, iNOS) and demonstrated anti-inflammatory efficacy higher than CRB. On comparison, ERB demonstrated exceptional efficacy by causing a reduction of 48% in ROS, 20% in TNF-α, and 23% in PGE2 at 10 μg/mL, surpassing the anti-inflammatory capabilities of all the bioactive compounds, FA and ORZ, respectively. At the same time, VRB exhibited remarkable efficacy by reducing NO production by 52% at 200 μg/mL and IL-6 by 66% at 10 μg/mL, surpassing FA, CAT, ORZ, and GTP. Further, ERB downregulated the mRNA expression of IL-10 and iNOS, while VRB downregulated TNF-α, IL-1β, and COX2 expression. Both extracts equally downregulated IL-6 expression at 10 μg/mL, demonstrating the efficacy more remarkable/on par with established anti-inflammatory compounds. ConclusionsOverall, enzyme-treated rice bran/extract, particularly ERB, possesses excellent anti-inflammatory properties, making them promising agents for alternatives to contemporary nutraceuticals/functional food against inflammatory diseases.

A comparative study on the influence of fiber enzymatic treatment in thermal, morphological and mechanical properties of PBS matrix reinforced with different date palm fibers: Under accelerated UV radiation exposure

The use of natural fiber-reinforced polymer materials has become increasingly common in various applications. However, the performance and durability of these composites in outdoor applications are not fully understood. Therefore, the objective of this study is to investigate the impact of an artificial ultraviolet radiation on the degradation behavior of composites based on a Poly Butylene Succinate (PBS) matrix. The reinforcement materials used in this research were the trunk and palm fibers obtained from date palm trees. Specifically, the effect of modifying the fiber surface with an enzymatic treatment on the interfacial adhesion fiber/matrix as well as on the rate of deterioration of the resulted composites, under accelerated aging, was assessed. Changes in the composite’s thermal stability, surface morphology and mechanical properties were determined after aging. A sharp transition in the behavior of the PBS matrix was observed after UV exposure, shifting from slight ductility following 100 h to brittleness after 700 h. The aging process resulted in a decrease in the thermal stability of all composites. However, the composites containing treated fibers exhibited better thermal stability compared to those with untreated fibers. Additionally, the use of enzyme-treated fibers in the composites promoted greater stability in the mechanical properties even after aging. The reinforcement of the composites with palm fibers yielded better interfacial adhesion compared to the use of trunk fibers, and resulted in better retention in the tensile strength property after aging. The enzymatic treatment facilitated stronger physical attachment between the fibers and the matrix, preventing any fiber or interface degradation.

Enzymatic treatment of pineapple pomace and its application into fiber-rich biscuit making

Pineapple pomace is a by-product of the pineapple juice industry. With high dietary fiber content, it has become a potential source added to fiber-rich foods in recent years. However, the ratio of soluble dietary fiber (SDF) to total dietary fiber (TDF) in pineapple pomace is very low while both SDF and insoluble dietary fiber (IDF) have positive effects on human health. In this study, the enzymatic treatment conditions of fresh pineapple pomace with commercial cellulase on its dietary fiber profile were investigated. The addition of non-enzyme-treated pineapple pomace (NTPP) and enzyme-treated pineapple pomace (ETPP) into biscuit formulation was then examined. The appropriate cellulolytic treatment conditions were the water content of 86 %, the cellulase concentration of 7.5 U/g dry matter, and the treatment time of 3 h, under which the SDF content was enhanced from 1.26 to 4.43 % while the SDF/TDF ratio was improved from 2.2 to 9.5 % as compared to those of NTPP. The use of NTPP or ETPP in biscuit formula increased TDF content and antioxidative capacities as well as hardness of the product. At the ratio of 30 %, the biscuits made with ETPP were lower in hardness, greater in SDF content, SDF/TDF ratio, antioxidative capacities, and overall organoleptic acceptance compared to the biscuits made with NTPP.

Enzymatic easing of adhesion in honeydew-contaminated cotton for textile applications

Purpose The textile sector struggles with cotton stickiness from honeydew contamination. It hurts agriculture and marketability. This study aims to examine how bacterial enzymes could reduce honeydew-contaminated cotton adherence in textile businesses sustainably. Design/methodology/approach Enzyme was extracted from bacteria isolated from the fermented bamboo shoots “Lung siej”. The enzyme was tested for α-glucosidase using p-nitrophenyl-α-D-glucopyranoside as a substrate. Design of experiments determined enzyme activity temperature and reaction time. Laboratory-prepared artificial honeydew was added to ginning mill cotton to show honeydew contamination. After enzyme treatment, sticky cotton was tested for microscopic examination, ultraviolet (UV), Benedict’s, Elsner colorimetric, high volume instrument (HVI) and viscosity tests. Findings The bacterial isolate is characterized as Lysinibacillus sp. as confirmed by 16S rRNA gene sequencing. The enzyme extracted was identified as α-glucosidase. The ideal temperature and reaction time for enzymatic activity were 32 °C and 35 min, respectively, using central composite design. The microscopic examination, UV test, Benedict’s test, Elsner colorimetric test, HVI test and viscosity test showed that bacterial enzyme treatment reduced cotton fiber adherence. Originality/value Although few patents have examined the effect of yeast enzymes, to the best of the authors’ knowledge, a bacterial enzyme is investigated for the first time to reduce the adhesion of honeydew-contaminated cotton.

Effects of transglutaminase treatment on cooking quality, textural properties, and overall acceptability of high fibre pasta incorporated with pennywort residue

Pennywort juice is a herbal drink extracted from pennywort leaves and stems. Pennywort residue is a by-product of pennywort juice production. In the present work, this by-product was proved to be a good dietary fibre ingredient in the making of high fibre pasta. Nevertheless, the addition of 10% pennywort residue reduced cooking properties, textural profiles, and overall acceptability of the pasta samples. The effects of transglutaminase treatment of pasta dough on the product quality were then investigated. Increase in transglutaminase dosage from 0.00 to 0.75 U/g protein of the flour blend decreased the cooking loss of pasta by 19% while improving its tensile strength and elongation rate by 15 and 49%, respectively. Further increase in enzyme dosage from 0.75 to 1.00 U/g protein, on the other hand, decreased the tensile strength and elongation rate. When the enzyme treatment lasted for 30 min, the cooking loss was reduced by 10%, while the tensile strength and elongation rate of high fibre pasta were both enhanced by 10%. However, increase in treatment time from 30 to 40 min did not cause any significant differences in textural and cooking properties of the fibre-rich pasta. The appropriate transglutaminase dosage and biocatalytic time were 0.75 U/g protein and 30 min, respectively, under which the overall acceptability of the sample incorporated with 10% pennywort residue powder was similar to that of the semolina pasta.

Pulse Protein Isolates as Competitive Food Ingredients: Origin, Composition, Functionalities, and the State-of-the-Art Manufacturing.

The ever-increasing world population and environmental stress are leading to surging demand for nutrient-rich food products with cleaner labeling and improved sustainability. Plant proteins, accordingly, are gaining enormous popularity compared with counterpart animal proteins in the food industry. While conventional plant protein sources, such as wheat and soy, cause concerns about their allergenicity, peas, beans, chickpeas, lentils, and other pulses are becoming important staples owing to their agronomic and nutritional benefits. However, the utilization of pulse proteins is still limited due to unclear pulse protein characteristics and the challenges of characterizing them from extensively diverse varieties within pulse crops. To address these challenges, the origins and compositions of pulse crops were first introduced, while an overarching description of pulse protein physiochemical properties, e.g., interfacial properties, aggregation behavior, solubility, etc., are presented. For further enhanced functionalities, appropriate modifications (including chemical, physical, and enzymatic treatment) are necessary. Among them, non-covalent complexation and enzymatic strategies are especially preferable during the value-added processing of clean-label pulse proteins for specific focus. This comprehensive review aims to provide an in-depth understanding of the interrelationships between the composition, structure, functional characteristics, and advanced modification strategies of pulse proteins, which is a pillar of high-performance pulse protein in future food manufacturing.

Isolation of an antitubercular protein from Staphylococcus hominis IS2 from the custard apple and evaluation of its biosafety

Tuberculosis (TB) is one of the leading causes of death throughout the world. Traditional medicine poses a serious challenge to drug resistance against Mycobacterium tuberculosis. Hence, it is an urgent need to develop, novel the anti-mycobacterial compounds. In this study, a potent anti-mycobacterial compound producing Staphylococcus hominis IS2 was isolated from the custard apple exhibiting novel anti-mycobacterial activity than other isolates. The bacterial strain was cultured and anti-mycobacterial compound was purified by the combination of ammonium sulphate precipitation and DEAE-cellulose column chromatography. The purified protein corresponding to 10 kDa presented anti-mycobacterial activity. It was further characterized and the difference in activity towards temperature and pH was observed (p < 0.01). The purified protein was analyzed using FT-IR and MALDI-TOF MS/MS analysis. Enzymatic treatment revealed the absence of carbohydrate moieties in the purified protein. The purified anti-mycobacterial protein presented anti-cancer activity against cervical cancer cell lines (HeLa) and was dose-dependent (p < 0.01). Haemolytic assay and Zebra fish embryo studies revealed that the isolated protein is safe at lower doses.

Laccase as a useful assistant for maize to accelerate the phenanthrene degradation in soil.

Polycyclic aromatic hydrocarbon (PAH) pollution has attracted much attention due to their wide distribution in soil environment and serious harm to human health. In order to establish an efficient and eco-friendly technology for remediation of PAH-contaminated soil, phytoremediation utilizing maize assisted with enzyme remediation was explored in this study. The results showed that the participation of laccase could promote the degradation of phenanthrene (PHE) from soil and significantly reduce the accumulation of PHE in maize. The degradation efficiency of PHE in soil could reach 77.19% under laccase-assisted maize remediation treatment, while the accumulation of PHE in maize roots and leaves decreased by 41.23% and 74.63%, respectively, compared to that without laccase treatment, after 24days of maize cultivation. Moreover, it was found that laccase addition shifted the soil microbial community structure and promoted the relative abundance of some PAH degrading bacteria, such as Pseudomonas and Sphingomonas. In addition, the activities of some enzymes that were involved in PAH degradation process and soil nutrient cycle increased with the treatment of laccase enzyme. Above all, the addition of laccase could not only improve the removal efficiency of PHE in soil, but also alter the soil environment and reduce the accumulation of PHE in maize. This study provided new perspective for exploring the efficiency of the laccase-assisted maize in the remediation of contaminated soil, evaluating the way for reducing the risk of secondary pollution of plants in the phytoremediation process.

Synergistic functionality of transglutaminase and protease on modulating texture of pea protein based yogurt alternative: From rheological and tribological characterizations to sensory perception

Although the general mechanism of transglutaminase (TGase) and protease on texturizing protein gels has been known, their synergistic functionalities on modulating the textural and sensory attributes of pea protein based yogurt alternative (PPBYA) are still not clear. In this work, 9 PPBYA gels treated by the mentioned enzymes were manufactured to investigate their texturizing functionality. By treating PPBYA milk (emulsion) with TGase (0.47 U/g protein), the resultant PPBYA gel had an increased strain resilience by ∼1.8-fold compared to blank control (γ-LVE); however, the brittleness of the gel was also increased by ∼4.8-fold (Index-FT). Co-application of TGase (0.47 U/g protein) and protease (0.1 U/g protein) seemed not to cause changes in some conventional rheological parameters as compared to the PPBYA control, for instance the referred parameters were strain resistance, hardness, and brittleness. However, the impact of mentioned synergistic enzymatic treatment on PPBYA gel may be clearly demonstrated by nonlinear rheological parameters; the Pipkin diagrams showed that co-application of TGase and protease resulted in PPBYA gels with higher homogeneity of dynamic rheology behavior in response to large deformation. Overall, the enzymatic treatments were able to result in significant changes in structure, rheology, tribology, and sensory attributes. Sensory textural attributes e.g. smoothness-in-mouth and astringency were both correlated with flow strain, whereas lubrication transition behavior was correlated with astringency. The obtained results demonstrated that the difference of textural characteristics between PPBYA and yogurt can be reduced by the co-application of TGase and protease at an optimized ratio and dosage rate.

A novel approach to analyze the impact of lytic polysaccharide monooxygenases (LPMOs) on cellulosic fibres

Enzymatic treatment of cellulosic fibres is a green alternative to classical chemical modification. For many applications, mild procedures for cellulose alteration are sufficient, in which the fibre structure and, therefore, the mechanical performance of cellulosic fibres are preserved. Lytic polysaccharide monooxygenases (LPMOs) bear a great potential to become a green reagent for such targeted cellulose modifications. An obstacle for wide implementation of LPMOs in tailored cellulose chemistry is the lack of suitable techniques to precisely monitor the LPMO impact on the polymer. Soluble oxidized cello-oligomers can be quantified using chromatographic and mass-spectrometric techniques. A considerable portion of the oxidized sites, however, remain on the insoluble cellulose fibres, and their quantification is difficult. Here, we describe a method for the simultaneous quantification of oxidized sites on cellulose fibres and changes in their molar mass distribution after treatment with LPMOs. The method is based on quantitative, heterogeneous, carbonyl-selective labelling with a fluorescent label (CCOA) followed by cellulose dissolution and size-exclusion chromatography (SEC). Application of the method to reactions of seven different LPMOs with pure cellulose fibres revealed pronounced functional differences between the enzymes, showing that this CCOA/SEC/MALS method is a promising tool to better understand the catalytic action of LPMOs.

The biopreservative properties of Metschnikowia pulcherrima LMA 2038 and Trichosporon asahii LMA 810 in a model fresh cheese, are presented

The diversity of microorganisms present in cheeses contributes to their typicity and organoleptic properties. Inhibitory strains found in these ecosystems could be used as biopreservative agents in order to replace chemicals, which are increasingly decried by consumers. Here, we isolated from cheese two yeasts named, Metschnikowia pulcherrima LMA 2038 and Trichosporon asahii LMA 810, which are active against fungi, such as Yarrowia lipolytica LMA 800, Rhodotorula mucilaginosa LMA 808, Cladosporium cladosporioides LMA 31, and Penicillium commune LMA 72, as well as against bacteria, such as Listeria innocua ATCC 33090 and Clostridium tyrobutyricum LMG 1285. When cultivated on model fresh cheese, these antagonistic yeasts significantly reduced the number of Y. lipolytica LMA 800 and R. mucilaginosa LMA 808. Preliminary data enabled us to establish a snapshot of the molecules responsible for these antifungal and antibacterial inhibitions. The molecules presumed to be present in the culture supernatant were subjected to various treatments, including heat, pH variations and enzymatic treatments. Thus, we hypothesize that different antimicrobial compounds were produced by the aforementioned antagonistic yeasts, and these molecules act in a target strain-specific manner. In summary, our findings demonstrate that cheeses possess an innumerable supply of antagonistic microbial strains, which can be exploited in the field of biopreservation to substitute chemicals and extend the shell-life of food products, including cheese.

The effect of tea catechins on the forensic identification of urine: Urine camouflage to evade drug tests

BackgroundWe encountered a urine sample suspected of being mixed with tea, submitted by a suspect attempting to camouflage illegal drugs. Although urine should turn reddish-pink during a urea test with p-Dimethylaminocinnamaldehyde (DAC), this suspect’s sample exhibited a blue coloration when tested with DAC. AimOur aim was to examine the influence and mechanism of green tea on various urine identification tests. ResultsOur examination revealed that DAC forms a compound with the urea in urine, resulting in a reddish pink coloration with a molecular weight of 217. However, it has been reported that DAC binds to polyphenols such as catechin. In the case of catechin, DAC binds to the C8 position, forming a compound that exhibits the highest absorption at 640 nm and appears blue. we investigated the effect of urine from volunteers who had consumed a large amount of catechin on the urea test with DAC. Additionally, we carried out quantitative analysis of catechin in urine by LC-MS/MS after enzymatic treatment with β-glucuronidase. The concentration of urinary excreted catechin reached its peak approximately 3 to 4 h after ingestion. During the DAC test, urine samples collected 3 to 4 h after catechin ingestion displayed a bluish pink color, but not the blue color observed in the original suspect sample. ConclusionThis study investigated the impact of catechin on urine tests, revealing that a blue color in the DAC test indicates a high likelihood of camouflage by the suspect.

Umbilical cord-derived mesenchymal stem cell sheets transplanted subcutaneously enhance cell retention and survival more than dissociated stem cell injections

BackgroundHuman umbilical cord-derived mesenchymal stem cell (hUC-MSC) sheets have recently attracted attention as an alternative approach to injected cell suspensions for stem cell therapy. However, cell engraftment and cytokine expression levels between hUC-MSC sheets and their cell suspensions in vivo have not yet been compared. This study compares hUC-MSC in vivo engraftment efficacy and cytokine expression for both hUC-MSC sheets and cell suspensions.MethodshUC-MSC sheets were prepared using temperature-responsive cell culture; two types of hUC-MSC suspensions were prepared, either by enzymatic treatment (trypsin) or by enzyme-free temperature reduction using temperature-responsive cell cultureware. hUC-MSC sheets and suspensions were transplanted subcutaneously into ICR mice through subcutaneous surgical placement and intravenous injection, respectively. hUC-MSC sheet engraftment after subcutaneous surgical transplantation was investigated by in vivo imaging while intravenously injected cell suspensions were analyzing using in vitro organ imaging. Cytokine levels in both transplant site tissues and blood were quantified by enzyme-linked immunosorbent assay.ResultsAfter subcutaneous transplant, hUC-MSC sheets exhibited longer engraftment duration than hUC-MSC suspensions. This was attributed to extracellular matrix (ECM) and cell–cell junctions retained in sheets but enzymatically altered in suspensions. hUC-MSC suspensions harvested using enzyme-free temperature reduction exhibited relatively long engraftment duration after intravenous injection compared to suspensions prepared using trypsin, as enzyme-free harvest preserved cellular ECM. High HGF and TGF-β1 levels were observed in sheet-transplanted sites compared to hUC-MSC suspension sites. However, no differences in human cytokine levels in murine blood were detected, indicating that hUC-MSC sheets might exert local paracrine rather than endocrine effects.ConclusionshUC-MSC sheet transplantation could be a more effective cell therapeutic approach due to enhanced engraftment and secretion of therapeutic cytokines over injected hUC-MSC suspensions.

Modelling biofilm development: The importance of considering the link between EPS distribution, detachment mechanisms and physical properties

In industry, treatments against biofilms need to be optimized and, in the wastewater treatment field, biofilm composition needs to be controlled. Therefore, describing the biochemical and physical structures of biofilms is now required to better understand the influence of operating parameters and treatment on biofilms. The present study aims to investigate how growth conditions influence EPS composition, biofilm physical properties and volume detachment using a 1D biofilm model. Two types of EPS are considered in the present model, proteins and polysaccharides. The main hypotheses are that: (i) the production of polysaccharides occurs mainly under strong nutrient limitation(s) while the production of proteins is coupled to both the substrate uptake rate and the lysis process; (ii) the local biofilm porosity depends on the local biofilm composition. Both volume and surface detachment occur in biofilms and volume detachment extent depends on the biofilm local cohesion and thus on the local composition of biofilms for a given shear stress.The model is based on experimental trends and aims to represent these observations on the basis of biochemical and physical processes. Four case studies covering a wide range of contrasting growth conditions such as different COD/N ratios, applied SOLR and shear stresses are investigated. The model predicts how the biochemical and physical biofilm structures change as a result of contrasting growth conditions. More precisely simulation results are in good agreement with the main experimental observations reported in the literature, such as: (i) a strong nitrogen limitation of growth induces an important accumulation of polysaccharides leading to a more porous and homogenous biofilm, (ii) a high applied surface organic loading load allows to obtain a high biofilm thickness, (iii) a strong shear stress applied during the biofilm growth leads to a reduction of the biofilm thickness and to a consolidation of the biofilm structure. Overall, this model represents a relevant decision tool for the selection of appropriate enzymatic treatments in the context of negative biofilm control. From our results, it appears that protease based treatments should be more appropriate for biofilms developed under low COD/N ratios (about 20 gCOD/gN) whereas both glucosidases and proteases based treatments should be more appropriate for biofilms developed under high COD/N ratio (about 70 gCOD/gN). In addition, the model could be useful for other applications such as resource recovery in biofilms or granules, and help to better understand biological membrane fouling.

Microwave-assisted enzymatic hydrolysis: A sustainable approach for enhanced structural and functional properties of broken rice protein

Design experiments having three levels of each processing parameter i.e.,α-amylase concentration (0.25–0.75%), extraction time (30–180 min), and temperature (30–60 °C) were conducted to investigate the effect of enzymatic pre-treatment on protein content and extracted yield from broken rice, an industrial by-product. Enzymatically pre-treated broken rice under optimal conditions (0.72% α-amylase concentration, 141 min extraction time, and 43°C of temperature) were subjected to microwave treatment followed by varying degrees (3%, 6%, 9%, and 12%) of enzymatic hydrolysis. The study revealed that the strongest free radical scavenging activity (72.35 ± 4.31 and 93.47 ± 1.25 μmol Trolox equivalent/g), highest magnitude of zeta potential (−24.95 ± 0.64 mV), and lowest mean particle size (446 ± 6.43 nm) were observed at MDH 12%. The FTIR analysis of MDH 12% (1650.08 cm−1) indicated a shift from random coil to β-turn, resulting unfolding of the rice protein structure and increased protein solubility. However, with an increase in DH, a negative effect on the foaming and emulsification properties of rice protein was observed. This study revealed that microwave-assisted enzymatic treatment with a 12% degree of hydrolysis can improve the functional properties of extracted protein and meet the demand for rice protein applications in different food formulations.

Biological activity of enzymolysed ɩ-carrageenan of polydisperse nature

Sulfated polysaccharides from algae exhibit bioactivities and offer various health benefits. However, high molecular weight often restricts the bioavailability of these natural products. Polysaccharides with lower molecular weight, on the other hand, play a crucial role in enhancing various bioactive properties, including antioxidant activity, tyrosinase inhibition, cell proliferation, and more. The goal of this study was to produce a series of medium and lower molecular weight (Mw) ι-carrageenan samples and evaluate their bioactive potential. The ι-carrageenan samples with varying degradation levels and polydispersities were obtained after enzymatic treatment using a ι-carrageenase obtained from the marine bacterium Cellulophaga baltica. Compared to the non-degraded ι-carrageenan (I-0), the most degraded sample (I-5) showed 2.5 and 1.5 times higher antioxidant activities and inhibition of tyrosinase enzyme, respectively. Anticoagulant activity dropped by 1.8 times after 1200 min enzymolysis. The cell viability of I-5 treated RAW 264.7 cells was enhanced up to 140.6 ± 3.4% in comparison to the non-degraded one, while the highest proliferation rate was observed on I-5 treated both RAW267.4 and HaCaT cells. In addition, I-5-treated RAW264.7 cells showed the highest amount of Nitric oxide (NO) reduction, indicating a beneficial effect on inflammation. HaCaT cells treated with I-5 could migrate almost 90% of the wound area within 24 h compared to I-0, and the scratch area was completely closed at 48 h. A lower inflammation rate and higher HaCaT cell proliferation rate in I-5 displayed the ideal characteristics of wound healing material. These findings indicate that enzyme-degraded ι-carrageenans could be promising therapeutic agents in the cosmeceutical and pharmaceutical industries.

Construction and Characterization of Fitting Equations for a New Wheat Straw Pulping Method.

The pretreatment of pulp with enzymes has been extensively studied in the laboratory. However, due to cost constraints, the application of enzymes in the pulp and paper industry is very limited. In this paper, an environment-friendly and efficient pulping method is proposed as an alternative to traditional pulping and papermaking methods. This new method overcomes the low efficiency and extreme pollution problems associated with traditional pulping methods. In addition, fitting equations for the new pulping method are constructed using data on enzyme treatments, which reflect the effect of enzymes and enable the realization of real-time control of the pulping process. The experimental results show that the efficiency of the pulping and papermaking process can be improved using biological enzymes, and the separation of cellulose can be facilitated using mixed enzymes, which have a better effect than single enzymes.

Lactoferrin-polyphenol composite nanocoating with enhanced chemical stability and cell-compatibility

Lactoferrin is a functional whey protein that exhibits beneficial bioactivities to human health. To utilize the wide range of lactoferrin's biomedical advantages, much effort has been devoted to developing lactoferrin coating strategies. However, lactoferrin coating has been still limited to the conventional protein modification techniques, which hamper the practical applications of lactoferrin. Here, we demonstrate lactoferrin composite nanocoating by layer-by-layer assembly with lactoferrin and Fe(III)-tannic acid complex. The simple immersive processes are able to deposit lactoferrin composite nanolayers on planar substrates with precise thickness tuneablility. Also, the optimized deposition condition for lactoferrin composite nanocoating is applicable to particulate substrates. Further, lactoferrin composite nanocoating shows enhanced nanofilm stability against pH changes and digestive enzyme treatments, and improves cell compatibility greatly, compared to that of Fe(III)-TA complex. We envisage that lactoferrin composite nanocoating not only paves the way for exploiting full potential of lactoferrin's bioactivities, but also leads to stimulating the tailored design of composite nanomaterials containing multiple enzymes for customized applications in nanomedicine and nanobiosensor.