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Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3050
Author(s):  
Mika Immonen ◽  
Julia Myllyviita ◽  
Tuula Sontag-Strohm ◽  
Päivi Myllärinen

The aim of this study was to develop an extraction method to produce highly functional oat protein concentrates. We investigated the possibility of combining enzyme-aided slightly alkaline (pH 8.0) extraction with ultrafiltration and subsequent diafiltration for concentration of the extracted oat proteins. A further aim was to study how the deamidation of oat proteins with protein-glutaminase (PG) improves the solubility of proteins as a function of the following parameters: pH (6.0–9.0), enzyme dosage (4–20 U/g protein), and incubation time (1–4 h) with response surface methodology (RSM). Furthermore, we investigated selected functional properties, such as heat-induced gelation and solubility, of the oat protein concentrates. The chosen parameters for the enzymatic deamidation pre-treatment process by PG were as follows: pH 8.0, dosage 11.0 U/g protein, and an incubation time of 4 h (1 h at native pH and 3 h at pH 8.0). Two oat protein concentrates were produced, non-deamidated and ultrafiltered, and deamidated and ultrafiltered, with protein concentrations of 45.0 and 52.4%, respectively. The solubility of both oat protein concentrates was significantly improved at neutral and slightly alkaline pH compared to the solubility of proteins extracted from the starting material. Additionally, both oat protein concentrates produced equally strong heat-induced gel-like structures at a protein concentration of 10%.


2021 ◽  
Vol 13 (12) ◽  
pp. 6520
Author(s):  
David San Martin ◽  
Jone Ibarruri ◽  
Bruno Iñarra ◽  
Nagore Luengo ◽  
Jorge Ferrer ◽  
...  

Brewer’s spent yeast (BSY) is produced by the beer industry and has high nutritional value and great potential for producing high-value molecules, such as peptides, for nutraceutical, food and feed applications. In the present research, Flavourzyme® and Protamex® enzymes were selected for protein hydrolysis based on previous studies. The optimum conditions for the enzymatic hydrolysis were defined by response surface methodology (RSM) by the Box–Behnken design composed of four variables: temperature, pH, enzyme dosage and time. Protein content, hydrolysis degree and the anti-microbial and antioxidant bioactivities of obtained hydrolysates were quantified. Obtained results show that time, enzyme dosage and pH had the highest effect on protein extraction yield (PEY), degree of hydrolysis (DH) and antioxidant activity. Response variables ranged from 13.7 to 29.7% for PEY, from 6.3 to 35.7% for DH and from 0.65 to 1.65 g for Trolox equivalent antioxidant capacity. Antimicrobial activity, measured as minimum inhibitory concentration, against Aeromonas salmonicida, Bacillus cereus, Bacillus subtilis and Salmonella enterica, ranged from 6.25 to 50 mg/mL. Antioxidant and antimicrobial activity showed the potential use of BSY hydrolysates as an ingredient for functional foods.


2021 ◽  
Vol 12 ◽  
Author(s):  
Kai Song ◽  
Jingjing Sun ◽  
Wei Wang ◽  
Jianhua Hao

In this study, the cgt gene my20, which encodes cyclodextrin glycosyltransferase (CGTase) and was obtained by the metagenome sequencing of marine microorganisms from the Mariana Trench, was codon optimized and connected to pET-24a for heterologous expression in Escherichia coli BL21(DE3). Through shaking flask fermentation, the optimized condition for recombinant CGTase expression was identified as 20°C for 18 h with 0.4 mM of isopropyl β-D-L-thiogalactopyranoside. The recombinant CGTase was purified by Ni2+-NTA resin, and the optimum pH and temperature were identified as pH 7 and 80°C, respectively. Activity was stable over wide temperature and pH ranges. After purification by Ni2+-NTA resin, the specific activity of the CGTase was 63.3 U/mg after 67.3-fold purification, with a final yield of 43.7%. In addition, the enzyme was used to transform L-ascorbic acid into 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G). The maximal AA-2G production reached 28 g/L, at 40°C, pH 4, 24 h reaction time, 50 g/L donor concentration, and 50 U/g enzyme dosage. The superior properties of recombinant CGTase strongly facilitate the industrial production of AA-2G.


2021 ◽  
Author(s):  
Ahmad Chaudhry

This study illustrates the potential opportunity for the utilization of hemp to produce PHB (poly(3-hydroxybutyrate). The objective of the study was to optimize simple sugar availability from hemp for Ralstonia eutropha. The use of three pre-treatment methods (grinded – 5% NaOH – Autoclave at 121 oC for 60 minutes) was able to provide a better fractional insoluble solids (FIS) of ≃ 61 % that was significantly better compared to other combinations of pre-treatments studied. Optimum enzyme dosage was also determined by comparing different enzyme concentrations and found that three enzymes should contain a dose of 1.5 g /L. The optimum pretreatment and hydrolysis conditions resulted in a better enzyme hydrolysis yield of 10.9 % and PHB yield of ≃ 43 %. Results also demonstrate that sonification did not improve PHB recovery, while pH control increased PHB recovery. Keywords: Hemp, Ralstonia eutropha, PHB, Pre-treatment, Enzyme Hydrolysis


2021 ◽  
Author(s):  
Ahmad Chaudhry

This study illustrates the potential opportunity for the utilization of hemp to produce PHB (poly(3-hydroxybutyrate). The objective of the study was to optimize simple sugar availability from hemp for Ralstonia eutropha. The use of three pre-treatment methods (grinded – 5% NaOH – Autoclave at 121 oC for 60 minutes) was able to provide a better fractional insoluble solids (FIS) of ≃ 61 % that was significantly better compared to other combinations of pre-treatments studied. Optimum enzyme dosage was also determined by comparing different enzyme concentrations and found that three enzymes should contain a dose of 1.5 g /L. The optimum pretreatment and hydrolysis conditions resulted in a better enzyme hydrolysis yield of 10.9 % and PHB yield of ≃ 43 %. Results also demonstrate that sonification did not improve PHB recovery, while pH control increased PHB recovery. Keywords: Hemp, Ralstonia eutropha, PHB, Pre-treatment, Enzyme Hydrolysis


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Luciana Sodre ◽  
Rosalia Huaira ◽  
Luciane Braga ◽  
Carlos Contreras ◽  
Fernando Colugnati ◽  
...  

Abstract Background and Aims Fabry disease is a chronic, progressive and multi-systemic hereditary condition, related to a Xq22 mutation in X chromosome, which results in deficiency of acid alpha-galactosidase, hence reduced capacity of globotriaosylceramide (Gb3) degradation. Gb3 accumulates in lysosomes throughout virtually every organ, thus causing considerable morbidity and mortality. Objectives: To evaluate the types of Fabry disease mutations and enzyme levels of Alpha Galactosidase and Lyso Gb3 in a multicenter study; the RIM FABRY BRASIL PROJECT. Method We conducted a transversal study that consists of data analysis secondary to the multicenter project: Clinical and Epidemiological Analysis of Fabry's Disease in Dialysis Centers in Brazil, “PROJETO RIM FABRY BRASIL”. Included 854 dialysis centers throughout Brazil and 75059 individuals screened using a questionnaire and signing an Informed Consent Form. The data were entered into a computer program (algorithm) that filters the possible carriers of Fabry's disease. The program / algorithm discarded those who probably did not have Fabry's disease and sent blood suspects to filter enzyme dosage and genetic testing of those suspected of the disease. Results 75059 individuals from the RIM FABRY BRASIL project were screened, where 58.37% were men and 41.54% women. 408 individuals with mutations for Fabry disease were identified, including patients with kidney and Family history of the disease, 34.6% men and 65.4% women with a mean age of 42.7 years. 47 different mutations were identified, with a higher prevalence of c.352C> T p.Arg118Cys (24.8%), followed by c.376A> G p.Ser126Gly (13.1%), c.1102G> A p.Ala368Thr ( 7.8%), c.937G> T p.Asp313Tyr (7.8%), c.870G> C p.Met290Ile (7.3%). Alfa GalA dosage was performed in 120 men, with 90% of them showing decreased enzyme and Lyso Gb3 dosage of 320 individuals, (36.2% men and 63.8% women) 72.5% normal and 27.5% increased. Conclusion The most frequent mutations were: c.352C> T p.Arg118Cys, followed by c.376A> G p.Ser126Gly, c.1102G> A p.Ala368Thr, c.937G> T p.Asp313Tyr, c.870G> C p.Met290Ile. 90% of men showed a decrease in the enzyme Alpha GalA and 27.5% of individuals had increased Lyso Gb3.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1473
Author(s):  
Licelander Hennessey-Ramos ◽  
Walter Murillo-Arango ◽  
Juliana Vasco-Correa ◽  
Isabel Cristina Paz Astudillo

Cocoa pod husks are a waste generated during the processing of cocoa beans. We aimed to explore the enzymatic extraction of pectin using cellulases. The extraction process was optimized using a central composite design (CCD) and analyzed by response surface methodology (RSM). The parameters optimized were feedstock concentration (%), enzyme dosage (µL/g), and time (h). Three dependent variables were studied: pectin yield (g/100 g dry husk) (R2 = 97.02), galacturonic acid content (g/100 g pectin) (R2 = 96.90), and galacturonic acid yield (g/100 g feedstock) (R2 = 95.35). The optimal parameters were 6.0% feedstock concentration, 40 µL g−1 of enzyme, and 18.54 h, conditions that produced experimentally a pectin yield of 10.20 g/100 g feedstock, 52.06 g galacturonic acid/100 g pectin, and a yield 5.31 g galacturonic acid/100 g feedstock. Using the chemical extraction method, a yield of 8.08 g pectin/100 g feedstock and a galacturonic acid content of 60.97 g/100 g pectin were obtained. Using assisted sonication, a pectin yield of 8.28 g/100 g feedstock and a galacturonic acid content of 42.77 g/100 g pectin were obtained. Enzymatically optimized pectin has rheological and physicochemical features typical of this biomaterial, which provides an interesting alternative for the valorization of cocoa husks.


Cellulose ◽  
2021 ◽  
Author(s):  
Aayush Kumar Jaiswal ◽  
Vinay Kumar ◽  
Alexey Khakalo ◽  
Panu Lahtinen ◽  
Katariina Solin ◽  
...  

AbstractHigh-consistency processing of fibrillated cellulose materials is attractive for commercial applications due to potential for lowered production costs, energy savings and easier logistics. The current work investigated structure–property relationships of fibrillated cellulose suspensions produced at 20% consistency using VTT HefCel (High-consistency enzymatic fibrillation of cellulose) technology. Morphological examination of the fibrillated materials revealed that enzymatic action on the cellulose substrates was not a direct function of enzyme dosage but rather was dependent on the raw material composition. Furthermore, shear viscosity of the HefCel suspensions was found to decrease with increasing enzyme dosage while the water retention increased. The shear viscosity followed power law relationship with the power law index varying in the range 0.11–0.73. The shear-thinning behavior decreased with increasing consistency. Moreover, suspension viscosity ($$\upmu$$ μ ) was found to be highly dependent on the consistency ($$\mathrm{c})$$ c ) as $$\upmu \sim {\mathrm{c}}^{\mathrm{m}}$$ μ ∼ c m , with $$\mathrm{m}$$ m ranging from 2.75 to 4.31 for different samples. Yield stress (τy) of the HefCel suspensions was measured at 7 and 10% consistencies. The performance of the fibrillated cellulose grades in a typical application was demonstrated by casting films, which were characterized for their mechanical properties. Graphic abstract


2020 ◽  
Vol 115 (12) ◽  
pp. 444-453
Author(s):  
Xu Zhang ◽  
Xiang Zhong ◽  
Mengchu Gao ◽  
Biyu Peng ◽  
Chunxiao Zhang

Most of the reported bating technologies for wet blue are based on the usage of acidic protease, which takes a long time and needs large enzyme dosage. A thorough understanding of the basic characteristics of typical acidic proteases and the interaction between enzyme proteins and wet blue fibers will help to improve bating technology for wet blue by selecting the suitable proteases. In this paper, the enzymatic characteristics, molecular weight (Mr) and isoelectric point (pI) of several proteases and their bating effectiveness were investigated. The results indicated that there are two main factors which may affect the wet blue bating effectiveness of acidic proteases. First, the common acidic proteases exhibited low activity towards chrome-tanned collagen fiber which lead to inefficient bating effect through normal dosage. Nonetheless, when the dosages of chrome-tanned collagen fiber activity reached up to 50 U/mL, these acidic proteases also can achieve a good bating effect, the caseinolytic activity has been reached up to 1000 U/mL-4000 U/mL. Second, because of the large molecular weight and the charge repulsion between enzyme proteins and wet blue fibers, the enzymatic hydrolysis process, the penetration and distribution of acidic protease proteins, into wet blue is very difficult. Additionally, neutral proteases have more prospects in wet blue bating process due to the higher chrome-tanned collagen fiber activity and less charge repulsion than acidic proteases.


Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1415
Author(s):  
Robert Gál ◽  
Pavel Mokrejš ◽  
Jana Pavlačková ◽  
Ngo Thi Hong Linh ◽  
Jiří Mlček

By-products of laying hens represent a promising raw material source with a high collagen content, which is currently not adequately used. The aim of the paper is to prepare gelatins from laying hen paws. The purified collagen raw material was processed by a biotechnological process using the food endoprotease Protamex®. After cleavage of the cross-links in the collagen structure, the gelatin was extracted by a batch process with a stirrer in two extraction steps. The influence of the extraction process on the yield of gelatins and on selected qualitative parameters of gelatins was monitored by two-level factor experiments with three selected process factors. The studied factors were: enzyme dosage (0.2–0.8%), enzyme processing time (24–72 h) and gelatin extraction time (30–120 min). After the first extraction step at 75 °C, gelatin was extracted with a yield of 8.2–21.4% and a gel strength of 275–380 Bloom. In the second extraction step at 80–100 °C, it is possible to obtain another portion (3.3–7.7%) of gelatin with a gel strength of 185–273 Bloom. Total extraction efficiency of gelatins prepared from laying hen collagen is almost 30%. The prepared gelatins are of high quality and, under proper extraction conditions, gelatins with a gel strength above 300 Bloom can be prepared, thus equaling commercial beef and pork gelatins of the highest quality. Biotechnological processing of laying hen collagen into gelatins is environmentally friendly.


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