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Background and Objectives: Kilning is crucial in oat processing, to prevent rancidity and extend shelf‐life. This study examines kilning effects on the macronutrient composition in Swedish oat varieties Galant, Fatima, and Belinda. We compared two kilning methods: one mimicking industrial practice and a simplified version. We analyzed dietary fibers (arabinoxylan, β‐glucan), protein and amino acids, lipid profile, lipase activity, and antioxidant capacity in these oat samples. Findings: Distinct compositional differences were found: Galant had low lipid content, Fatima had elevated lipid and protein levels with fewer carbohydrates, and Belinda was rich in β‐glucan and dietary fibers. Both kilning procedures had similar impacts on all varieties, causing no major changes in dietary fiber or total protein content, but resulting in a 20% decrease in soluble proteins. Kilning decreased levels of several amino acids in Belinda, while the l‐glutamate/glutamine ratio increased across all varieties. Lipid analysis showed minimal kilning‐induced changes; yet, antioxidative capacity diminished. Both kilning methods effectively inactivated lipases. Conclusions: These findings emphasize macronutrient variations among oat varieties and the effect of kilning on soluble proteins, amino acids, and antioxidative capacity. Significance and Novelty: This study underscores the need for precise control in oat processing, crucial in plant‐based protein and novel food development for optimal quality and yield. [ABSTRACT FROM AUTHOR]

Phlorotannins are bioactive polyphenols in brown macroalgae that make these algae interesting as healthy food. Specific phlorotannins are, however, seldom identified, and extracts from different species are often only analysed for total phenolic content (TPC). In this study, our focus was to identify phlorotannin molecules from Saccharina latissima and Ascophyllum nodosum (a species rich in these compounds) using ultra-high-performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS2). Water and ethanol (30 and 80% v/v) were used at solid:liquid ratios, extraction times and temperatures, proposed to result in high TPC in extracts from other species. The S. latissima extracts, however, did not allow phlorotannin detection by either UHPLC-UV/Vis or UHPLC-HRMS2, despite a TPC response by the Folin–Ciocalteu assay, pinpointing a problem with interference by non-phenolic compounds. Purification by solid phase extraction (SPE) led to purer, more concentrated fractions and identification of four phlorotannin species in A. nodosum and one in S. latissima by UHPLC-HRMS2, using extracts in ethanol 80% v/v at a solid:liquid ratio of 1:10 for 20 h at 25 °C with an added 10 h at 65 °C incubation of remaining solids. The phlorotannin with the formula C12H10O7 (corresponding to bifuhalol) is the first identified in S. latissima. [ABSTRACT FROM AUTHOR]

Oat ( Avena sativa ) is a cereal grain rich in fibers, proteins, vitamins and minerals. Oats have been linked to several health benefits, such as lowering blood cholesterol levels, counteracting cardiovascular disease and regulating blood sugar levels. This study aimed to characterize two new oat lines with high β-glucan content emanating from ethyl methyl sulphonate mutagenesis on the Lantmännen elite variety Belinda. Two of the mutated lines, and the mother variety Belinda, were profiled for β-glucan, arabinoxylan, total dietary fiber and starch composition. In addition, total lipid and protein content, amino acid composition and β-glucan molecular weights were analyzed. The high levels of β-glucan resulted in a significant increase in total dietary fiber, but no correlation could be established between higher or lower levels of the assayed macromolecules, i.e., between arabinoxylan-, starch-, lipid- or protein levels in the mutated lines compared to the reference. The results indicate separate biosynthetic pathways for β-glucans and other macromolecules and an independent regulation of the different polysaccharides studied. Therefore, ethyl methyl sulphonate mutagenesis can be used to increase levels of multiple macromolecules in the same line., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Oat (Avena sativa) is a nutritionally important cereal crop that is rich in health-promoting dietary fibers, favorable proteins and polar lipids. In this work, ca. 500 random lines of a mutagenized oat population of high genetic variation were screened for arabinoxylan (AX) content. This identified lines with up to 60% higher AX levels in flour from whole seed and up to 100% higher in flour from dehulled seeds, as compared to the original Belinda variety. In addition, the cellular localization of AX was determined in cross-sections of dehulled seeds from three high and one low AX line using a xylan-specific antibody. This revealed variations in the amount and localization of AX between high and low AX lines. The high AX lines will now serve as a starting point in the development of oat varieties with superior health-promoting and rheological properties., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Marine macroalgal (seaweed) polysaccharides are highly promising for next-generation applications in several industries. However, despite the reported comprehensive potential of these polysaccharides, commercial products are scarce on the market. Seaweed cultivations are increasing in number and production quantity, owing to an elevated global trend of utilization interest in seaweed. The extraction of polysaccharides from seaweed generally generates low yields, but novel methods are being developed to facilitate and improve the extraction processes. Current areas of applications for seaweed polysaccharides mainly take advantage of the physicochemical properties of certain polysaccharides, such as gelling, thickening and emulsifying. However, many of the numerous bioactivities reported are still only at research level and lack clinical evidence for commercialization. It has been suggested the construction of smaller units may generate better defined molecules that are more suitable for biomedical applications. Enzymatic modification is a promising tool for the generation of more defined, targeted biomolecules. This review covers; structural differences between the most predominant marine algal polysaccharides, extraction processes, modification alternatives, as well as a summary of current and potential next-generation application areas., Competing Interests: The authors declare no conflict of interest.

Brewer's spent grain (BSG) accounts for around 85% of the solid by-products from beer production. BSG was first extracted to obtain water-soluble arabinoxylan (AX). Using subsequent alkali extraction (0.5 M KOH) it was possible to dissolve additional AX. In total, about 57% of the AX in BSG was extracted with the purity of 45-55%. After comparison of nine xylanases, Pentopan mono BG, a GH11 enzyme, was selected for hydrolysis of the extracts to oligosaccharides with minimal formation of monosaccharides. Growth of Bifidobacterium adolescentis (ATCC 15703) was promoted by the enzymatic hydrolysis to arabinoxylooligosaccharides, while Lactobacillus brevis (DSMZ 1264) utilized only unsubstituted xylooligosaccharides. Furthermore, utilization of the hydrolysates by human gut microbiota was also assessed in a batch human fecal fermentation model. Results revealed that the rates of fermentation of the BSG hydrolysates by human gut microbiota were similar to that of commercial prebiotic fructooligosaccharides, while inulin was fermented at a slower rate. In summary, a sustainable process to valorize BSG to functional food ingredients has been proposed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Rhodothermus marinus, a marine aerobic thermophile, was first isolated from an intertidal hot spring in Iceland. In recent years, the R. marinus strain PRI 493 has been genetically modified, which opens up possibilities for targeted metabolic engineering of the species, such as of the carotenoid biosynthetic pathway. In this study, the carotenoids of the R. marinus type-strain DSM 4252 T , strain DSM 4253, and strain PRI 493 were characterized. Bioreactor cultivations were used for pressurized liquid extraction and analyzed by ultra-high performance supercritical fluid chromatography with diode array and quadropole time-of-flight mass spectrometry detection (UHPSFC-DAD-QTOF/MS). Salinixanthin, a carotenoid originally found in Salinibacter ruber and previously detected in strain DSM 4253, was identified in all three R. marinus strains, both in the hydroxylated and nonhydroxylated form. Furthermore, an additional and structurally distinct carotenoid was detected in the three strains. MS/MS fragmentation implied that the mass difference between salinixanthin and the novel carotenoid structure corresponded to the absence of a 4-keto group on the ß-ionone ring. The study confirmed the lack of carotenoids for the strain SB-71 (ΔtrpBΔpurAcrtBI'::trpB) in which genes encoding two enzymes of the proposed pathway are partially deleted. Moreover, antioxidant capacity was detected in extracts of all the examined R. marinus strains and found to be 2-4 times lower for the knock-out strain SB-71. A gene cluster with 11 genes in two operons in the R. marinusDSM 4252 T genome was identified and analyzed, in which several genes were matched with carotenoid biosynthetic pathway genes in other organisms., (© 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

The thermophile Rhodothermus marinus produces extracellular polysaccharides (EPSs) that forms a distinct cellular capsule. Here, the first data on EPS production in strains DSM4252 T and MAT493 are reported and compared. Cultures of both strains, supplemented with either glucose, sucrose, lactose or maltose showed that the EPS were produced both in the exponential and stationary growth phase and that production in the exponential phase was boosted by maltose supplementation, while stationary phase production was boosted by lactose. The latter was higher, resulting in 8.8 (DSM4252 T ) and 13.7mg EPS/g cell dry weight (MAT493) in cultures in marine broth supplemented with 10g/L lactose. The EPSs were heteropolymeric with an average molecular weight of 8×10 4 Da and different monosaccharides, including arabinose and xylose. FT-IR spectroscopy revealed presence of hydroxyl, carboxyl, N-acetyl, amine, and sulfate ester groups, showing that R. marinus produces unusual sulfated EPS with high arabinose and xylose content., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Poly(3-hydroxypropionate), P(3HP), is a polymer combining good biodegradability with favorable material properties. In the present study, a production system for P(3HP) was designed, comprising conversion of glycerol to 3-hydroxypropionaldehyde (3HPA) as equilibrium mixture with 3HPA-hydrate and -dimer in aqueous system (reuterin) using resting cells of native Lactobacillus reuteri in a first stage followed by transformation of the 3HPA to P(3HP) using recombinant Escherichia coli strain co-expressing highly active coenzyme A-acylating propionaldehyde dehydrogenase (PduP) from L. reuteri and polyhydroxyalkanoate synthase (PhaCcs) from Chromobacterium sp. P(3HP) content of up to 40% (w/w) cell dry weight was reached, and the yield with respect to the reuterin consumed by the cells was 78%. Short biotransformation period (4.5h), lack of additives or expensive cofactors, and use of a cheap medium for cultivation of the recombinant strain, provides a new efficient and potentially economical system for P(3HP) production., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

3-Hydroxypropionic acid (3-HP) is an important platform chemical for the biobased chemical industry. Lactobacillus reuteri produces 3-HP from glycerol via 3-hydroxypropionaldehyde (3-HPA) through a CoA-dependent propanediol utilization (Pdu) pathway. This study was performed to verify and evaluate the pathway comprising propionaldehyde dehydrogenase (PduP), phosphotransacylase (PduL), and propionate kinase (PduW) for formation of 3-HP from 3-HPA. The pathway was confirmed using recombinant Escherichia coli co-expressing PduP, PduL and PduW of L. reuteri DSM 20016 and mutants lacking expression of either enzyme. Growing and resting cells of the recombinant strain produced 3-HP with a yield of 0.3mol/mol and 1mol/mol, respectively, from 3-HPA. 3-HP was the sole product with resting cells, while growing cells produced 1,3-propanediol as co-product. 3-HP production from glycerol was achieved with a yield of 0.68mol/mol by feeding recombinant E. coli with 3-HPA produced by L. reuteri and recovered using bisulfite-functionalized resin., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

3-Hydroxypropionaldehyde (3HPA), a potential C3-platform chemical for a biobased industry, is produced from glycerol using Lactobacillus reuteri through its glycerol dehydratase activity. However, the process is characterized by low yield and productivity due to toxic effects of 3HPA on the biocatalyst activity. In this study, a semicarbazide-functionalized resin was prepared, evaluated for adsorption and in situ recovery of 3HPA during biotransformation of glycerol. Adsorption of 3HPA onto the resin was characterized as “S-curve model”, increasing with increasing initial 3HPA concentration, and reached a maximum of 9.48 mmol/g(resin) at 71.54 mM 3HPA used. Desorption of 3HPA was evaluated using water and different acids, and was enhanced by acetic acid with organic modifiers. Repeated adsorption–desorption of 3HPA in batch resulted in elution of 13–66.5% of the bound 3HPA during at least three sequential cycles using water and acetic acid, respectively as eluants. Using the resin for in situ product removal led to more than 2 times higher productivity of 3HPA.

3-Hydroxypropionaldehyde (3HPA) is an important C3 chemical that can be produced from renewable glycerol by resting whole cells of Lactobacillus reuteri. However the process efficiency is limited due to substrate inhibition, product-mediated loss of enzyme activity and cell viability, and also formation of by-products. Complex formation of 3HPA with sodium bisulfite and subsequent binding to Amberlite IRA-400 was investigated as a means of in situ product recovery and for overcoming inhibition. The adsorption capacity and -isotherm of the resin were evaluated using the Langmuir model. The resin exhibited maximum capacity of 2.92 mmol complex/g when equilibrated with 45 mL solution containing an equilibrium mixture of 2.74 mmol 3HPA-bisulfite complex and 2.01 mmol free 3HPA. The dynamic binding capacity based on the breakthrough curve of 3HPA and its complex on passing a solution with 2.49 mmol complex and 1.65 mmol free 3HPA was 2.01 mmol/g resin. The bound 3HPA was desorbed from the resin using 0.20 M NaCl with a high purity as a mixture of complexed- and free 3HPA at a ratio of 0.77 mol/mol. Fed-batch biotransformation of glycerol (818.85 mmol) with in situ 3HPA complexation and separation on the bisulfite-functionalized resin resulted in an improved process with consumption of 481.36 mmol glycerol yielding 325.54 mmol 3HPA at a rate of 17.13 mmol/h and a yield of 68 mol%. Also, the cell activity was maintained for at least 28 h., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Production of propionic acid by fermentation of glycerol as a renewable resource has been suggested as a means for developing an environmentally-friendly route for this commodity chemical. However, in order to quantify the environmental benefits, life cycle assessment of the production, including raw materials, fermentation, upstream and downstream processing is required. The economic viability of the process also needs to be analysed to make sure that any environmental savings can be realised. In this study an environmental and economic assessment from cradle-to-gate has been conducted. The study highlights the need for a highly efficient bioprocess in terms of product titre (more than 100g/L and productivity more than 2g/(L · h)) in order to be sustainable. The importance of the raw materials and energy production for operating the process to minimize emissions of greenhouse gases is also shown., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

3-Hydroxypropionic acid (3-HP), an important C3 chemical for a bio-based industry, is natively produced by Lactobacillus reuteri from glycerol. Conversion of glycerol occurs via the intermediate 3-hydroxypropionaldehyde (3-HPA), followed by an ATP-producing pathway initiated by the CoA-acylating propionaldehyde dehydrogenase (PduP). The pduP gene of L. reuteri was cloned and expressed in Escherichia coli and the recombinant enzyme was purified to homogeneity for characterization of its activity and properties. Kinetic studies with propionaldehyde as substrate showed a maximum specific activity of 28.9 U/mg, which is 80-fold higher than that reported previously. Maximum activity of 18 U/mg was obtained at 3-HPA concentration of 7 mM, above which substrate inhibition was observed. Substrate inhibition was also seen with coenzyme A at a concentration above 0.5mM and with NADP(+) above 9 mM. A structure of PduP is proposed based on homology modeling. In silico docking of the co-factors coenzyme A and NAD(+), respectively, showed a common binding site consisting of amino acids Thr145, Ile275, Cys277 and Ser417, which through site-directed mutagenesis to alanine and kinetic studies, were confirmed as essential for the catalytic activity of PduP., (Copyright © 2013 Elsevier Inc. All rights reserved.)

3-Hydroxypropionaldehyde (3HPA) is an important specialty chemical which can be produced from glycerol using resting cells of Lactobacillus reuteri. This biocatalytic route, however, suffers from substrate- and product-mediated loss of enzyme activity within 2 h of biotransformation. In order to overcome the inhibitory effects of 3HPA, complex formation with sodium bisulfite was investigated, optimized and applied for in situ capture of the aldehyde during biotransformation of glycerol in a fed-batch process. As a result, the activity of the cells was maintained for at least 18 h. The 3HPA produced per gram cell dry weight was increased 5.7 times compared to the batch production process, and 2.2 times compared to fed-batch process without in situ complex formation. This approach may have potential for production and in situ removal of 3HPA after further process development., (Copyright © 2012 Wiley Periodicals, Inc.)