Browsing by Subject "FIBER"

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  • Vuorinne, Ilja; Heiskanen, Janne; Maghenda, Marianne; Mwangala, Lucas; Muukkonen, Petteri; Pellikka, Petri K.E. (2021)
    Biomass is a key variable for crop monitoring and for assessing carbon stocks and bioenergy potential. This study aimed to develop an allometric model for predicting the dry leaf biomass of sisal, an agave plant with crassulacean acid metabolism grown for fibre production in the tropics and subtropics and whose biomass can be utilised as a feedstock to produce biogas through anaerobic digestion. The allometric model was used to estimate leaf biomass and productivity across different stand ages in a sisal plantation in semi-arid region in south-east Kenya (annual rainfall 611 mm and temperature 24.9 °C). Based on a sample of 38 leaves, the best predictor for biomass was leaf maximum width and plant height used as a combined variable in a log-log regression model (cross-validated R2 = 0.96 and root-mean-square error = 7.69 g). The mean productivity in nine 26- to 36-month-old plots was 11.1 Mg ha−1 yr−1, which could potentially yield approximately 3000 m3 CH4 ha−1 yr−1. The leaf biomass in 55 field plots (400 m2 in area) ranged from 2.7 to 42.7 Mg ha−1, with mean at 13.5 Mg ha−1, which equals to 6.3 Mg C ha−1. The yielded allometric equations can be utilised for predicting the leaf biomass of sisal in similar agro-ecological zones. The estimates on plantation biomass can be used in assessing the role of sisal plantations as a regional carbon storage. In addition, the results provide reference on the productivity of agave and crassulacean acid metabolism in semi-arid regions of East Africa, where such reports are few.
  • Koponen, Kari K.; Salosensaari, Aaro; Ruuskanen, Matti O.; Havulinna, Aki S.; Männistö, Satu; Jousilahti, Pekka; Palmu, Joonatan; Salido, Rodolfo; Sanders, Karenina; Brennan, Caitriona; Humphrey, Gregory C.; Sanders, Jon G.; Meric, Guillaume; Cheng, Susan; Inouye, Michael; Jain, Mohit; Niiranen, Teemu J.; Valsta, Liisa M.; Knight, Rob; Salomaa, Veikko V. (2021)
    Background: Diet has a major influence on the human gut microbiota, which has been linked to health and disease. However, epidemiological studies on associations of a healthy diet with the microbiota utilizing a whole-diet approach are still scant. Objectives: To assess associations between healthy food choices and human gut microbiota composition, and to determine the strength of association with functional potential. Methods: This population-based study sample consisted of 4930 participants (ages 25-74; 53% women) in the FINRISK 2002 study. Intakes of recommended foods were assessed using a food propensity questionnaire, and responses were transformed into healthy food choices (HFC) scores. Microbial diversity (alpha diversity) and compositional differences (beta diversity) and their associations with the HFC score and its components were assessed using linear regression. Multiple permutational multivariate ANOVAs were run from whole-metagenome shallow shotgun-sequenced samples. Associations between specific taxa and HFC were analyzed using linear regression. Functional associations were derived from Kyoto Encyclopedia of Genes and Genomes orthologies with linear regression models. Results: Both microbial alpha diversity (beta/SD, 0.044; SE, 6.18 x 10(-5); P = 2.21 x 10(-3)) and beta diversity (R-2, 0.12; P Conclusions: Our results from a large, population-based survey confirm and extend findings of other, smaller-scale studies that plant and fiber-rich dietary choices are associated with a more diverse and compositionally distinct microbiota, and with a greater potential to produce SCFAs.
  • Heiniö, Camilla; Sorsa, Suvi; Siurala, Mikko; Grönberg-Vähä-Koskela, Susanna; Havunen, Riikka; Haavisto, Elina; Koski, Anniina; Hemminki, Otto; Zafar, Sadia; Cervera-Carrascon, Victor; Munaro, Eleonora; Kanerva, Anna; Hemminki, Akseli (2019)
    After the discovery and characterization of the adenovirus in the 1950s, this prevalent cause of the common cold and other usually mild diseases has been modified and utilized in biomedicine in several ways. To date, adenoviruses are the most frequently used vectors and therapeutic (e.g., oncolytic) agents with a number of beneficial features. They infect both dividing and nondividing cells, enable high-level, transient protein expression, and are easy to amplify to high concentrations. As an important and versatile research tool, it is of essence to understand the limits and advantages that genetic modification of adenovirus vectors may entail. Therefore, a retrospective analysis was performed of adenoviral gene therapy constructs produced in the same laboratory with similar methods. The aim was to assess the impact of various modifications on the physical and functional titer of the virus. It was found that genome size (designed within "the 105% golden rule") did not significantly affect the physical titer of the adenovirus preparations, regardless of the type of transgene (e.g., immunostimulatory vs. other), number of engineered changes, and size of the mutated virus genome. One statistically significant exception was noted, however. Chimeric adenoviruses (5/3) had a slightly lower physical titer compared to Ad5-based viruses, although a trend for the opposite was true for functional titers. Thus, 5/3 chimeric viruses may in fact be appealing from a safety versus efficacy viewpoint. Armed viruses had lower functional and physical titers than unarmed viruses, while five genomic modifications started to decrease functional titer. Importantly, even highly modified armed viruses generally had good titers compatible with clinical testing. In summary, this paper shows the plasticity of adenovirus for various vector, oncolytic, and armed oncolytic uses. These results inform future generations of adenovirus-based drugs for human use. This information is directly transferable to academic laboratories and the biomedical industry involved in vector design and production optimization.
  • Mganga, Kevin Z.; Ndathi, Aphaxard J. N.; Wambua, Stephen M.; Bosma, Luwieke; Kaindi, Eric M.; Kioko, Theophilus; Kadenyi, Nancy; Musyoki, Gilbert K.; van Steenbergen, Frank; Musimba, Nashon K. R. (2021)
    Context. Rangeland grasses native to Africa constitute the main diet for free-ranging livestock and wild herbivores. Leaf:stem ratio is a key characteristic used for assessing quality of forages. However, studies to determine the allocation of biomass to leaves and stems as well as chemical components and nutritive value, especially of grasses in African rangelands, are rare. Aim. This study was conducted to establish biomass allocation and chemical and mineral components in leaf and stem fractions of three grasses, Eragrostis superba, Enteropogon macrostachyus and Cenchrus ciliaris, all indigenous to African rangelands. Methods. Plant height, plant densities, plant tiller densities and biomass yields were estimated at the elongation stage, before inflorescence. Chemical and mineral components were determined from biomass harvested at the vegetative phase for all three grass species. Dry matter, ash content, organic matter, crude protein, neutral detergent fibre, acid detergent fibre, acid detergent lignin, and calcium, phosphorus and potassium contents were determined. Key results. Enteropogon macrostachyus displayed significantly greater plant and tiller densities and plant height than the other two species. Leaf and stem biomass fractions varied significantly (P <0.05) among grasses. Leaf:stem ratio of E. superba was double that of E. macrostachyus and C. ciliaris. Crude protein and organic matter yields and net energy for lactation were highest (P <0.05) in E. superba leaf biomass, as was Ca content. Conclusions. Eragrostis superba demonstrated greater potential as a forage species for ruminant animal production than E. macrostachyus and C. ciliaris. Implications. Eragrostis superba is a key forage species that warrants promotion in pasture establishment programs in its native environments.
  • Korpela, Katri; Kallio, Sampo; Salonen, Anne; Hero, Matti; Kukkonen, Anna Kaarina; Miettinen, Päivi J.; Savilahti, Erkki; Kohva, Ella; Kariola, Laura; Suutela, Maria; Tarkkanen, Annika; de Vos, Willem M.; Raivio, Taneli; Kuitunen, Mikael (2021)
    Accumulating evidence indicates that gut microbiota may regulate sex-hormone levels in the host, with effects on reproductive health. Very little is known about the development of intestinal microbiota during puberty in humans. To assess the connection between pubertal timing and fecal microbiota, and to assess how fecal microbiota develop during puberty in comparison with adult microbiota, we utilized a Finnish allergy-prevention-trial cohort (Flora). Data collected at 13-year follow-up were compared with adult data from a different Finnish cohort. Among the 13-year-old participants we collected questionnaire information, growth data from school-health-system records and fecal samples from 148 participants. Reference adult fecal samples were received from the Health and Early Life Microbiota (HELMi) cohort (n=840). Fecal microbiota were analyzed using 16S rRNA gene amplicon sequencing; the data were correlated with pubertal timing and compared with data on adult microbiota. Probiotic intervention in the allergy-prevention-trial cohort was considered as a confounding factor only. The main outcome was composition of the microbiota in relation to pubertal timing (time to/from peak growth velocity) in both sexes separately, and similarity to adult microbiota. In girls, fecal microbiota became more adult-like with pubertal progression (p= 0.009). No such development was observed in boys (p = 0.9). Both sexes showed a trend towards increasing relative abundance of estrogen-metabolizing Clostridia and decreasing Bacteroidia with pubertal development, but this was statistically significant in girls only (p = 0.03). In girls, pubertal timing was associated positively with exposure to cephalosporins prior to the age of 10. Our data support the hypothesis that gut microbiota, particularly members of Ruminococcaceae, may affect pubertal timing, possibly via regulating host sex-hormone levels.
  • Kakko, Tia; King, Alistair W. T.; Kilpeläinen, Ilkka (2017)
    Cellulose acetate is widely used in films, filters, textiles, lacquer and cosmetic products. Herein we demonstrate the production of cellulose esters under homogeneous conditions using 1,5-diazabicyclo[4.3.0]non-5-ene acetate ([DBNH][OAc]) as solvent. The reagents have been chosen such that the system is recyclable, i.e. by-products are low boiling and easy to remove. It is demonstrated that cellulose acetate can be synthesized with different degree of substitution (DS) values, and that some commonly used acylation regents, like vinyl carboxylates react well without additional base catalyst. Low to high DS values are possible with good recovery of high purity ionic liquid (IL). A linear correlation method of two separate methods, IR and P-31 NMR, is proposed to reliably assess the DS of the products. The recyclability of the solvent is demonstrated by acetylating cellulose with isopropenyl acetate to high degree and regeneration into water. After regeneration of cellulose acetate from the IL with addition of water, the residual water was entrained using n-butanol to minimize hydrolysis of [DBNH][OAc], to allow for high recovery and high purity of the ionic liquid. Thus, an overall scheme for batch cellulose acetylation and recovery of [DBNH][OAc] from aqueous solutions is proposed.
  • Ylinen, Vappu; Pylkko, Paivi; Peura, Jussi; Valaja, Jarmo (2020)
    To formulate low-protein diets for blue foxes with sufficient amounts of amino acids (AA), AA digestibility and AA requirements of the animals are crucial information. Therefore, a digestibility and nitrogen (N) balance trial was conducted with 20 blue foxes to determine the macronutrient and AA digestibility and N utilisation in low-protein diets supplemented with DL-methionine (Met) and L-histidine (His). In addition, plasma urea and plasma AA were measured. The diets were designated as P24 (control), P20, P20M, P16M and P16MH and contained energy from digestible crude protein (DCP) at 24%, 20% or 16% of total dietary metabolisable energy (ME). The 20% protein level was fed with or without Met and the 16% protein level was fed with Met and with or without His. The apparent total-tract digestibility (ATTD) of crude protein linearly decreased with decreasing dietary protein level. The ATTD of dry matter, organic matter and crude carbohydrates increased when wheat starch was added as a replacement for protein. The apparent ileal digestibility (AID) and ATTD methods were compared to determine the AA digestibility. The decreasing dietary protein supply decreased the ATTD of most of the AA: threonine, tryptophan (Trp), valine, alanine (Ala), aspartic acid (Asp), glutamic acid, glycine (Gly), proline (Pro), serine (Ser) and total AA. The AID of the AA was constant between diets. Diverging AA showed higher or lower digestibility when determined in the AID or ATTD methods. Isoleucine, lysine, Met, Ala and tyrosine showed higher levels of AID. Arginine, His, cysteine (Cys), Trp, Asp, Gly, Pro and Ser showed higher levels of ATTD, which may reflect the net loss of these AA in the large intestine. Met and His supplementation improved the ATTD and AID of the AA in question, respectively, but did not affect the other variables examined. N retention did not differ between diets and renal N excretion decreased with decreasing protein level; thus N utilisation improved. It was concluded that the protein supply and AA composition in low-protein diets with supplemented Met were adequate for adult blue foxes, since the lower protein supply improved N utilisation and did not affect N retention. However, His supplementation failed to reach the designed level and therefore showed no clear results.
  • Li, Xinpei; Lan, Hangzhen; Hartonen, Kari; Jussila, Matti; Wang, Xinghua; Riekkola, Marja-Liisa (2020)
    Today, wide variety of adsorbents have been developed for sample pretreatment to concentrate and separate harmful substances. However, only a few solid phase microextraction Arrow adsorbents are commercially available. In this study, we developed a new solid phase microextraction Arrow coating, in which nanosheets layered double hydroxides and poly(vinylpyrrolidone) were utilized as the extraction phase and poly(vinyl chloride) as the adhesive. This new coating entailed higher extraction capacity for several volatile organic compounds (allyl methyl sulfide, methyl propyl sulfide, 3-pentanone, 2-butanone, and methyl isobutyl ketone) compared to the commercial Carboxen 1000/polydimethylsiloxane coating. Fabrication parameters for the coating were optimized and extraction and desorption conditions were investigated. The validation of the new solid phase microextraction Arrow coating was accomplished using water sample spiked with volatile organic compounds. Under the optimal conditions, the limits of quantification for the five volatile organic compounds by the new solid phase microextraction Arrow coating and developed gas chromatography with mass spectrometry method were in the range of 0.2-4.6 ng/mL. The proposed method was briefly applied for enrichment of volatile organic compounds in sludge.
  • Laatikainen, R.; Koskenpato, J.; Hongisto, S. -M.; Loponen, J.; Poussa, T.; Hillilä, Markku; Korpela, R. (2016)
    BackgroundGrains are high in FODMAPs (Fermentable Oligo-, Di-, Monosaccharides And Polyols) and often considered as triggers of IBS symptoms. AimTo evaluate if rye bread low in FODMAPs would be better tolerated than regular rye bread in subjects with IBS. MethodsThe study was conducted as a randomised double blind controlled cross-over study (n=87). Participants were supplied with both regular rye bread and low-FODMAP rye bread for 4weeks. Symptoms were measured with a symptom severity scoring system (IBS-SSS) and visual analogue scale (VAS) assessments of individual symptoms. Quality of life was monitored. Colonic fermentation was measured by the breath hydrogen test and dietary intake by food diaries. ResultsDietary fibre intake increased during both study periods compared to baseline. Many signs of IBS i.e. flatulence, abdominal pain, cramps and stomach rumbling were milder on the low-FODMAP rye bread (P-values: 0.04; 0.049; 0.01 and 0.001). The mean of VAS measurements was favourable towards LF bread [-3 (95% CI): -6 to -1, P=0.02] but no differences were detected in IBS-SSS or quality of life. The AUC of breath hydrogen values was significantly lower during the low-FODMAP bread period (median 52.9 vs. 72.6; P=0.01). ConclusionsLow-FODMAP rye bread helps IBS patients to control their symptoms and reduces gastrointestinal gas accumulation. However, replacing regular rye bread by low-FODMAP bread without concomitant broader dietary changes does not improve quality of life or IBS-SSS. Nonetheless, inclusion of low-FODMAP rye bread in diet might be one way that IBS patients could increase their fibre intake.
  • Rosell, Frank; Cross, Hannah B.; Johnsen, Christin B.; Sundell, Janne; Zedrosser, Andreas (2019)
    The invasion of a species can cause population reduction or extinction of a similar native species due to replacement competition. There is a potential risk that the native Eurasian beaver (Castor fiber) may eventually be competitively excluded by the invasive North American beaver (C. canadensis) from areas where they overlap in Eurasia. Yet currently available methods of census and population estimates are costly and time-consuming. In a laboratory environment, we investigated the potential of using dogs (Canis lupus familiaris) as a conservation tool to determine whether the Eurasian or the North American beaver is present in a specific beaver colony. We hypothesized that dogs can discriminate between the two beaver species, via the odorant signal of castoreum from males and females, in two floor platform experiments. We show that dogs detect scent differences between the two species, both from dead beaver samples and from scent marks collected in the field. Our results suggest that dogs can be used as an "animal biosensor" to discriminate olfactory signals of beaver species, however more tests are needed. Next step should be to test if dogs discern between beaver species in the field under a range of weather conditions and habitat types and use beaver samples collected from areas where the two species share the same habitat. So far, our results show that dogs can be used as a promising tool in the future to promote conservation of the native beaver species and eradication of the invasive one. We therefore conclude that dogs may be an efficient non-invasive tool to help conservationist to manage invasive species in Europe, and advocate for European wildlife agencies to invest in this new tool.
  • Nieminen, Heikki J.; Laidmae, Ivo; Salmi, Ari; Rauhala, Timo; Paulin, Tor; Heinämäki, Jyrki; Haeggström, Edward (2018)
    Electrospinning is commonly used to produce polymeric nanofibers. Potential applications for such fibers include novel drug delivery systems, tissue engineering scaffolds, and filters. Electrospinning, however, has shortcomings such as needle clogging and limited ability to control the fiber-properties in a non-chemical manner. This study reports on an orifice-less technique that employs high-intensity focused ultrasound, i.e. ultrasound-enhanced electrospinning. Ultrasound bursts were used to generate a liquid protrusion with a Taylor cone from the surface of a polymer solution of polyethylene oxide. When the polymer was charged with a high negative voltage, nanofibers jetted off from the tip of the protrusion landed on an electrically grounded target held at a constant distance from the tip. Controlling the ultrasound characteristics permitted physical modification of the nanofiber topography at will without using supplemental chemical intervention. Possible applications of tailor-made fibers generated by ultrasound-enhanced electrospinning include pharmaceutical controlled-release applications and biomedical scaffolds with spatial gradients in fiber thickness and mechanical properties.
  • Laaksonen, Tiina; Helminen, Jussi K. J.; Lemetti, Laura; Långbacka, Jesper; del Cerro, Daniel Rico; Hummel, Michael; Filpponen, Ilari; Rantamaki, Antti H.; Kakko, Tia; Kemell, Marianna L.; Wiedmer, Susanne K.; Heikkinen, Sami; Kilpeläinen, Ilkka; King, Alistair W. T. (2017)
    Ionic liquids are used to dewater a suspension of birch Kraft pulp cellulose nanofibrils (CNF) and as a medium for water-free topochemical modification of the nanocellulose (a process denoted as "WtF-Nano"). Acetylation was applied as a model reaction to investigate the degree of modification and scope of effective ionic liquid structures. Little difference in reactivity was observed when water was removed, after introduction of an ionic liquid or molecular co-solvent. However, the viscoelastic properties of the CNF suspended in two ionic liquids show that the more basic, but non-dissolving ionic liquid, allows for better solvation of the CNF. Vibrio fischeri bacterial tests show that all ionic liquids in this study were harmless. Scanning electron microscopy and wide-angle X-ray scattering on regenerated samples show that the acetylated CNF is still in a fibrillar form. 1D and 2D NMR analyses, after direct dissolution in a novel ionic liquid electrolyte solution, indicate that both cellulose and residual xylan on the surface of the nanofibrils reacts to give acetate esters.