| 1. |
- Carrasco, Cristhian, et al.
(författare)
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Hydrothermal pretreatment of water-extracted and aqueous ethanol-extracted quinoa stalks for enzymatic saccharification of cellulose
- 2021
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Ingår i: Energies. - : MDPI. - 1996-1073. ; 14:14
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Tidskriftsartikel (refereegranskat)abstract
- Auto-catalyzed hydrothermal pretreatment (A-HTP) and sulfuric-acid-catalyzed hydrothermal pretreatment (SA-HTP) were applied to quinoa stalks in order to reduce their recalcitrance towards enzymatic saccharification. Prior to pretreatment, quinoa stalks were extracted with either water or a 50:50 (v/v) ethanol–water mixture for removing saponins. Extraction with water or aqueous ethanol, respectively, led to removal of 52 and 75% (w/w) of the saponins contained in the raw material. Preliminary extraction of quinoa stalks allowed for a lower overall severity during pretreatment, and it led to an increase of glucan recovery in the pretreated solids (above 90%) compared with that of non-extracted quinoa stalks (73–74%). Furthermore, preliminary extraction resulted in enhanced hydrolysis of hemicelluloses and lower by-product formation during pretreatment. The enhancement of hemicelluloses hydrolysis by pre-extraction was more noticeable for SA-HTP than for A-HTP. As a result of the pretreatment, glucan susceptibility towards enzymatic hydrolysis was remarkably improved, and the overall conversion values were higher for the pre-extracted materials (up to 83%) than for the non-extracted ones (64–69%). Higher overall conversion was achieved for the aqueous ethanol-extracted quinoa stalks (72–83%) than for the water-extracted material (65–74%).
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| 2. |
- Chambi, Diego, et al.
(författare)
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Production of Exopolysaccharides by Cultivation of Halotolerant Bacillus atrophaeus BU4 in Glucose- and Xylose-Based Synthetic Media and in Hydrolysates of Quinoa Stalks
- 2022
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Ingår i: Fermentation. - : MDPI AG. - 2311-5637. ; 8:2
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Tidskriftsartikel (refereegranskat)abstract
- A halotolerant, exopolysaccharide-producing bacterium isolated from the Salar de Uyuni salt flat in Bolivia was identified as Bacillus atrophaeus using next-generation sequencing. Comparisons indicate that the genome most likely (p-value: 0.0024) belongs to a subspecies previously not represented in the database. The growth of the bacterial strain and its ability to produce exopolysaccharides (EPS) in synthetic media with glucose or xylose as carbon sources, and in hydrolysates of quinoa stalks, was investigated. The strain grew well in all synthetic media, but the growth in glucose was better than that in xylose. Sugar consumption was better when initial concentrations were low. The growth was good in enzymatically produced cellulosic hydrolysates but was inhibited in hemicellulosic hydrolysates produced using hydrothermal pretreatment. The EPS yields were up to 0.064 g/g on initial glucose and 0.047 g/g on initial xylose, and was higher in media with relatively low sugar concentrations. The EPS was isolated and purified by a sequential procedure including centrifugation, cold ethanol precipitation, trichloroacetic acid treatment, dialysis, and freeze-drying. Glucose and mannose were the main sugars identified in hydrolyzed EPS. The EPS was characterized by size-exclusion chromatography, Fourier-transform infrared (FTIR) spectroscopy, heteronuclear single-quantum coherence nuclear magnetic resonance (HSQC NMR) spectroscopy, scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis. No major differences were elucidated between EPS resulting from cultivations in glucose- or-xylose-based synthetic media, while some divergences with regard to molecular-weight averages and FTIR and HSQC NMR spectra were detected for EPS from hydrolysate-based media.
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| 3. |
- Dell'Isola, Andrea, et al.
(författare)
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Education, Home Exercise, and Supervised Exercise for People With Hip and Knee Osteoarthritis As Part of a Nationwide Implementation Program : Data From the Better Management of Patients With Osteoarthritis Registry
- 2020
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Ingår i: Arthritis Care and Research. - : Wiley. - 2151-464X .- 2151-4658. ; 72:2, s. 201-207
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To compare the effectiveness of education (ED) plus home exercise (HE) and ED plus supervised exercise (SE) according to information provided by the Better Management of Patients With Osteoarthritis (BOA) Registry, a nationally implemented rehabilitation program for patients with hip and knee osteoarthritis (OA). In addition, we investigated whether or not the effect of the treatments differed based on the joint affected by OA (hip versus knee). Methods: We included 38,030 participants from the BOA Registry with knee or hip OA who were treated with either ED, HE, or SE. The effect of the 3 treatment options on the pain intensity reduction (range 0–10) immediately postintervention and at 12 months was estimated using a mixed-effects model adjusted for age, sex, body mass index, affected joint (hip or knee), pain at baseline, comorbidity, and level of education. Results: The participants undergoing HE or SE experienced a greater pain reduction compared to participants who received ED, both after the treatment (group mean change for ED –0.91 [95% confidence interval (95% CI) –1.15, –0.68], for HE –1.06 [95% CI –1.10, –1.01], and for SE –1.12 [95% CI –1.15, –1.08]) and at 12 months (group mean change for ED –0.58 [95% CI –0.87, –0.30], for HE –0.82 [95% CI –0.87, –0.76], and for SE –0.82 [95% CI –0.86, –0.77]). Patients with knee OA who underwent HE or SE improved more compared to patients with hip OA at both follow-ups. Conclusion: In primary care, HE and SE lead to similar reductions in pain intensity but are more effective than ED alone. In addition, people with knee OA benefit more from HE and SE than people with hip OA.
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| 4. |
- Dell'Isola, Andrea, et al.
(författare)
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Factors Associated With the Outcome of a First-Line Intervention for Patients With Hip or Knee Osteoarthritis or Both : Data From the BOA Register
- 2020
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Ingår i: Physical Therapy. - : Oxford University Press (OUP). - 0031-9023 .- 1538-6724. ; 100:10, s. 1771-1781
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: This study explored the association of patients' demographics, health status, symptom severity, previous osteoarthritis (OA) care, and psychological status with the change in pain severity following a first-line intervention including education and exercise for OA provided nationwide in Swedish primary care. METHODS: This register-based cohort study included 23,309 people with knee or hip OA from the Better Management of Patients with OA register. Linear regression models were used to assess the association of independent variables with the change in pain from baseline to 3 and 12 months. All the analyses were stratified based on the affected joint (hip vs knee). RESULTS: In people with hip and people with knee OA, high levels of baseline pain were associated with decreased pain at both follow-ups (3 months: knee B = -.67; hip B = -.64; 12 months: knee B = -.70; hip B = -.66), whereas being older, overweight, or female had a weak or no association. Finally, at both follow-ups, bilateral OA was associated with increased pain only in people with knee OA, whereas comorbidities and the willingness to undergo surgery were associated with increased pain regardless of the affected joint. CONCLUSIONS: Baseline pain showed the strongest association among the analyzed variables, whereas sex, age, and body mass index appear to be weakly associated with the pain change after a first-line intervention. Comorbidities and willingness to undergo surgery showed a potentially important association and may have a negative impact on the pain change following a first-line intervention. IMPACT: In people with hip or knee OA, age, sex, body mass index, and previous surgery are only weakly associated with the change in pain after a first-line intervention supporting the evidence recommending exercise and education as a foundation for all OA therapy. Having comorbidities and being willing to undergo surgery is associated with a worse outcome from a first-line intervention, including exercise and education. Individualized treatments addressing the disease perception and the specific comorbidity profile may improve the outcomes.
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| 5. |
- Dell’Isola, Andrea, et al.
(författare)
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Willingness to Undergo Joint Surgery Following a First-Line Intervention for Osteoarthritis : Data From the Better Management of People With Osteoarthritis Register
- 2021
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Ingår i: Arthritis care & research. - : John Wiley & Sons. - 2151-464X .- 2151-4658. ; 73:6, s. 818-827
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: to assess the proportion of participants reconsidering their willingness to undergo surgery after three and 12 months. Secondary aims are to analyse and compare the characteristics of people willing and unwilling to undergo joint surgery for osteoarthritis (OA) before a first-line intervention; to study the association between pain intensity, walking difficulties, self-efficacy and fear of movement with the willingness to undergo surgery.DESIGN: This is an observational study based on Swedish register data. We included 30,578 people with knee or hip OA who participated in a first-line intervention including education and exercise.RESULTS: People willing to undergo surgery at baseline showed a higher proportion of men (40% vs 27%) and more severe symptoms and disability. Respectively, 45% and 30% of the people with knee and hip OA who were willing to undergo surgery at baseline became unwilling after the intervention. At the end of the study period (12 months), 35% and 19% of those with knee and hip OA, respectively, who were willing to undergo surgery at baseline became unwilling. High pain intensity, walking difficulties, and fear of movement were associated with higher odds of being willing to undergo surgery at both follow-ups while increased self-efficacy showed the opposite association.CONCLUSIONS: A first-line intervention for OA is associated with reduced willingness to undergo surgery with a greater proportion among knee OA than hip OA people. Due to its temporal variability, willingness to undergo surgery should be used with care to deem surgery eligibility.
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| 6. |
- Dell'Isola, Andrea, et al.
(författare)
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Willingness to undergo joint surgery following a first-line intervention for osteoarthritis: data from the BOA register.
- 2021
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Ingår i: Arthritis care & research. - : Wiley. - 2151-4658 .- 2151-464X. ; 73:6, s. 818-827
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Tidskriftsartikel (refereegranskat)abstract
- to assess the proportion of participants reconsidering their willingness to undergo surgery after three and 12 months. Secondary aims are to analyse and compare the characteristics of people willing and unwilling to undergo joint surgery for osteoarthritis (OA) before a first-line intervention; to study the association between pain intensity, walking difficulties, self-efficacy and fear of movement with the willingness to undergo surgery.This is an observational study based on Swedish register data. We included 30,578 people with knee or hip OA who participated in a first-line intervention including education and exercise.People willing to undergo surgery at baseline showed a higher proportion of men (40% vs 27%) and more severe symptoms and disability. Respectively, 45% and 30% of the people with knee and hip OA who were willing to undergo surgery at baseline became unwilling after the intervention. At the end of the study period (12 months), 35% and 19% of those with knee and hip OA, respectively, who were willing to undergo surgery at baseline became unwilling. High pain intensity, walking difficulties, and fear of movement were associated with higher odds of being willing to undergo surgery at both follow-ups while increased self-efficacy showed the opposite association.A first-line intervention for OA is associated with reduced willingness to undergo surgery with a greater proportion among knee OA than hip OA people. Due to its temporal variability, willingness to undergo surgery should be used with care to deem surgery eligibility.
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| 7. |
- Derba-Maceluch, Marta, et al.
(författare)
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Impact of xylan on field productivity and wood saccharification properties in aspen
- 2023
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Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Xylan that comprises roughly 25% of hardwood biomass is undesirable in biorefinery applications involving saccharification and fermentation. Efforts to reduce xylan levels have therefore been made in many species, usually resulting in improved saccharification. However, such modified plants have not yet been tested under field conditions. Here we evaluate the field performance of transgenic hybrid aspen lines with reduced xylan levels and assess their usefulness as short-rotation feedstocks for biorefineries. Three types of transgenic lines were tested in four-year field tests with RNAi constructs targeting either Populus GT43 clades B and C (GT43BC) corresponding to Arabidopsis clades IRX9 and IRX14, respectively, involved in xylan backbone biosynthesis, GATL1.1 corresponding to AtGALT1 involved in xylan reducing end sequence biosynthesis, or ASPR1 encoding an atypical aspartate protease. Their productivity, wood quality traits, and saccharification efficiency were analyzed. The only lines differing significantly from the wild type with respect to growth and biotic stress resistance were the ASPR1 lines, whose stems were roughly 10% shorter and narrower and leaves showed increased arthropod damage. GT43BC lines exhibited no growth advantage in the field despite their superior growth in greenhouse experiments. Wood from the ASPR1 and GT43BC lines had slightly reduced density due to thinner cell walls and, in the case of ASPR1, larger cell diameters. The xylan was less extractable by alkali but more hydrolysable by acid, had increased glucuronosylation, and its content was reduced in all three types of transgenic lines. The hemicellulose size distribution in the GALT1.1 and ASPR1 lines was skewed towards higher molecular mass compared to the wild type. These results provide experimental evidence that GATL1.1 functions in xylan biosynthesis and suggest that ASPR1 may regulate this process. In saccharification without pretreatment, lines of all three constructs provided 8-11% higher average glucose yields than wild-type plants. In saccharification with acid pretreatment, the GT43BC construct provided a 10% yield increase on average. The best transgenic lines of each construct are thus predicted to modestly outperform the wild type in terms of glucose yields per hectare. The field evaluation of transgenic xylan-reduced aspen represents an important step towards more productive feedstocks for biorefineries. Copyright © 2023 Derba-Maceluch, Sivan, Donev, Gandla, Yassin, Vaasan, Heinonen, Andersson, Amini, Scheepers, Johansson, Vilaplana, Albrectsen, Hertzberg, Jönsson and Mellerowicz.
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| 8. |
- Derba-Maceluch, Marta, et al.
(författare)
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Xylan glucuronic acid side chains fix suberin-like aliphatic compounds to wood cell walls
- 2023
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Ingår i: New Phytologist. - : John Wiley & Sons. - 0028-646X .- 1469-8137. ; 238:1, s. 297-312
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Tidskriftsartikel (refereegranskat)abstract
- Wood is the most important repository of assimilated carbon in the biosphere, in the form of large polymers (cellulose, hemicelluloses including glucuronoxylan, and lignin) that interactively form a composite, together with soluble extractives including phenolic and aliphatic compounds. Molecular interactions among these compounds are not fully understood.We have targeted the expression of a fungal α-glucuronidase to the wood cell wall of aspen (Populus tremula L. × tremuloides Michx.) and Arabidopsis (Arabidopsis thaliana (L.) Heynh), to decrease contents of the 4-O-methyl glucuronopyranose acid (mGlcA) substituent of xylan, to elucidate mGlcA's functions.The enzyme affected the content of aliphatic insoluble cell wall components having composition similar to suberin, which required mGlcA for binding to cell walls. Such suberin-like compounds have been previously identified in decayed wood, but here, we show their presence in healthy wood of both hardwood and softwood species. By contrast, γ-ester bonds between mGlcA and lignin were insensitive to cell wall-localized α-glucuronidase, supporting the intracellular formation of these bonds.These findings challenge the current view of the wood cell wall composition and reveal a novel function of mGlcA substituent of xylan in fastening of suberin-like compounds to cell wall. They also suggest an intracellular initiation of lignin–carbohydrate complex assembly.
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| 9. |
- Donev, Evgeniy N., et al.
(författare)
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Field testing of transgenic aspen from large greenhouse screening identifies unexpected winners
- 2023
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Ingår i: Plant Biotechnology Journal. - : Wiley. - 1467-7644 .- 1467-7652. ; 21:5, s. 1005-1021
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Tidskriftsartikel (refereegranskat)abstract
- Trees constitute promising renewable feedstocks for biorefinery using biochemical conversion, but their recalcitrance restricts their attractiveness for the industry. To obtain trees with reduced recalcitrance, large-scale genetic engineering experiments were performed in hybrid aspen blindly targeting genes expressed during wood formation and 32 lines representing seven constructs were selected for characterization in the field. Here we report phenotypes of five-year old trees considering 49 traits related to growth and wood properties. The best performing construct considering growth and glucose yield in saccharification with acid pretreatment had suppressed expression of the gene encoding an uncharacterized 2-oxoglutarate-dependent dioxygenase (2OGD). It showed minor changes in wood chemistry but increased nanoporosity and glucose conversion. Suppressed levels of SUCROSE SYNTHASE, (SuSy), CINNAMATE 4-HYDROXYLASE (C4H) and increased levels of GTPase activating protein for ADP-ribosylation factor ZAC led to significant growth reductions and anatomical abnormalities. However, C4H and SuSy constructs greatly improved glucose yields in saccharification without and with pretreatment, respectively. Traits associated with high glucose yields were different for saccharification with and without pretreatment. While carbohydrates, phenolics and tension wood contents positively impacted the yields without pretreatment and growth, lignin content and S/G ratio were negative factors, the yields with pretreatment positively correlated with S lignin and negatively with carbohydrate contents. The genotypes with high glucose yields had increased nanoporosity and mGlcA/Xyl ratio, and some had shorter polymers extractable with subcritical water compared to wild-type. The pilot-scale industrial-like pretreatment of best-performing 2OGD construct confirmed its superior sugar yields, supporting our strategy.
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| 10. |
- Eriksson, Göran, et al.
(författare)
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A new maximal bicycle test using a prediction algorithm developed from four large COPD studies
- 2020
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Ingår i: European clinical respiratory journal. - : Informa UK Limited. - 2001-8525. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Maximum exercise workload (WMAX) is today assessed as the first part of Cardiopulmonary Exercise testing. The WMAX test exposes patients with COPD, often having cardiovascular comorbidity, to risks. Our research project was initiated with the final aim to eliminate the WMAX test and replace this test with a predicted value of WMAX, based on a prediction algorithm of WMAX derived from multicentre studies. Methods: Baseline data (WMAX, demography, lung function parameters) from 850 COPD patients from four multicentre studies were collected and standardized. A prediction algorithm was prepared using Random Forest modelling. Predicted values of WMAX were used in a new WMAX test, which used a linear increase in order to reach the predicted WMAX within 8 min. The new WMAX test was compared with the standard stepwise WMAX test in a pilot study including 15 patients with mild/moderate COPD. Results: The best prediction algorithm of WMAX included age, sex, height, weight, and six lung function parameters. FEV1 and DLCO were the most important predictors. The new WMAX test had a better correlation (R2 = 0.84) between predicted and measured WMAX than the standard WMAX test (R2 = 0.66), with slopes of 0.50 and 0.46, respectively. The results from the new WMAX test and the standard WMAX test correlated well. Conclusion: A prediction algorithm based on data from four large multicentre studies was used in a new WMAX test. The prediction algorithm provided reliable values of predicted WMAX. In comparison with the standard WMAX test, the new WMAX test provided similar overall results.
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