Maatalous- metsätieteellinen tiedekunta

 

Recent Submissions

  • Grammatikopoulou, Ioanna (Helsingin yliopisto, 2016)
    Agricultural lands are managed or modified ecosystems that interact with the surrounding natural environment so as to supply while also to use a great range of ecosystem services (ES). In addition, agriculture is responsible for disservices that negatively affect natural ecosystems. In Finland, agricultural lands have undergone marked changes affecting a great number of vital ES. Traditional agri-environmental policy has been criticized for being inefficient in ensuring the provision of ES or limiting the disservices, while markets have been unable to reflect the demand for or supply of ES due to the public character of some ES. Market-based mechanisms as well as targeted policy measures may ensure effective and efficient ES provision. This dissertation explores the factors that determine the citizen demand for and landowner supply of ES, and considers examples of market- and target-based measures that may supplement or replace the current form of agri-environmental policy. The first part of the dissertation is focused on the demand for and supply of cultural ES provided by agricultural lands. A choice experiment was applied to evaluate a marketbased scheme, i.e. a Payment for Ecosystem Services (PES) scheme that provides certain landscape attributes in a typical agricultural area. The analysis revealed that the most valued attributes were the renovation of production buildings and the presence of grazing animals. The results demonstrated that citizen preferences were heterogeneous, a fact which may affect the level of transaction costs and the performance of the scheme. Landowners were skeptical towards the scheme, willing to provide ES that did not always match with the demand. They also demanded compensation in excess of their expenses. Nonetheless, cost benefit considerations revealed that the scheme may be feasible, as the aggregated welfare benefits outweigh the anticipated costs. The second part is focused on the supply of water conservation services and the avoidance of water eutrophication disservices. During the data collection, Finnish agrienvironmental policy set equal incentives for water conservation, not accounting for environmental conditions, which are spatially varied. Before suggesting any policy reform and the use of alternative measures such as target-based measures, where farmers are compensated for delivering certain ES, it is imperative to investigate the tendency of landowners to adopt water conservation measures. By combining survey data with GIS data, a binary choice model was employed. The model examined the adoption of special measures for water conservation if the soil quality implies a high leaching risk and if the water quality is already poor. Adoption in areas under risk was weakly supported by the study s estimates. This indicates that environmental awareness, assuming it increases with risk, is not strong enough to motivate adoption. Target-based which are spatially tailored measures can attract adopters in hotspot areas. The latter outcome leads to the last subject, which examines farmers participation in an agri-environmental auction scheme. According to the outcomes of the study, farmers who have previously participated in a pilot auction scheme were more likely to be participants in future auctions. The findings also suggested a strong relationship between attitudes and participation, particularly for attitudes related to specific environmental benefits attached to the auction scheme, novelty and financial features, as well as the complexity of the auction mechanism. The ES and disservices examined in this dissertation, i.e. landscape amenities and water eutrophication, are of priority. Finnish agricultural landscape has experienced severe stresses during the past years while the state of the Baltic Sea is largely affected by the eutrophication issues of water bodies. The empirical research findings enhance current knowledge in planning market- and target-based schemes in the years to come. These schemes are attracting increasing attention for being more effective and, if properly designed, more efficient. For agri-environmental auctions in particular, the findings are novel, since they were derived from the first auction experiment ever implemented in Finland.
  • Koskela, Elli (Helsingin yliopisto, 2016)
    Strawberries (Fragaria sp.) belong to the large family of Rosaceae that includes commercially important crop plants such as apple, pear, peach and roses. The economic impact of these species is huge and breeders around the world are striving to keep up with consumers' demands on novelty produce. At the same time, climate change is having an impact on the onset of flowering especially in species that are grown in temperate climates. As flowering is a prerequisite for yield formation, it is extremely important to gain an insight on how the environmental factors, most importantly photoperiod and temperature, affect the timing of flowering in Rosaceous species. Although studying flowering responses directly in the cultivated species could provide immediate practical applications, it is often not feasible due to e.g. complex genomics of the species, large plant size or long juvenile period. The woodland strawberry (Fragaria vesca) (L.) has arisen as a convenient model plant for strawberries and the entire Rose family. It is a diploid species and therefore has a less complex genome than the cultivated octoploid strawberry. The work described here begun by elucidating the molecular identity of SEASONAL FLOWERING LOCUS (SFL), a locus controlling the switch from seasonal to continuous flowering habit in woodland strawberry. SFL was identified as the woodland strawberry orthologue of TERMINAL FLOWER1 (FvTFL1) based on its location on the strawberry genome and similarity to its Arabidopsis counterpart, TFL1. In woodland strawberry, FvTFL1 was shown to be photoperiodically regulated, and it was demonstrated that the continuous flowering habit is caused by a mutation at FvTFL1. In the following experiments, altered regulation of FvTFL1 was associated with the unique vernalisation requirement in the artic F. vesca accession Alta-1, suggesting a previously uncharacterised function for a TFL1 orthologue. The findings on FvTFL1 were extended to cultivated strawberry. It was demonstrated that F. × ananassa homologue of TFL1 (FaTFL1) also represses flowering, and that differences in the regulation of FaTFL1> were associated with different flowering times in strawberry cultivars. The finding that FaTFL1 is a major determinant in the flowering response of cultivated strawberry provides breeders with a new breeding target; producing cultivars with lowered FaTFL1 expression level could expand the flowering and fruiting season of strawberries. These results clearly demonstrate the feasibility of the model plant approach and also highlight the importance of fundamental research. The knowledge gained on fundamental genetic pathways in model plants can be transferred to crop plants, in which similar genetic studies would be impossible or at least extremely complex, slow and costly to perform
  • Holopainen, Jani (Finnish Society of Forest Science, 2016)
    The forest sector has been able to develop many new bio-based and sustainable products catered to business-to-business markets, but the sector still lacks a breakthrough in new forest products and services targeting consumer markets. This is due to higher prices of forest products compared to competing materials, such as concrete, steel, and plastics, but also due to a lack of new product and service innovations targeting end-consumer markets. To understand the emergence of bioeconomy, also bringing new consumer market opportunities to the forest sector, we need to understand the new business ecosystem. The business ecosystem model is a holistic view of the current institutions capturing stakeholder relations and opportunities brought by various resources and technologies. Better understanding of these concepts can lead to consumer-driven development of forest products and services, and improved competitive advantage. This doctoral dissertation introduces a holistic research and development model for new product and service innovations in the forest sector. This research was motivated by the fact that recent forest sector product introductions have been driven by the technology push, and therefore, this research concentrates on the consumer perspective to build new business models and the development of products and services to meet current consumer trends. Evolving sustainability trends among consumers, where bio-based forest products and services can fulfill consumer demand, are central in this thesis. The doctoral thesis consists of one book chapter and three peer-reviewed articles, each using different methodologies. The subjects and results of the papers are grouped into three themes in the framework of the Consumer-Driven Business Ecosystem Research and Development (CDBERD) model. The model extends the classical technology-push and demand-pull innovation model, to better consider consumer values, enabling resources and dominant logics along with the smooth flow of information during each phase of the research and development process leading towards new consumer-driven solutions.
  • D'Amato, Dalia (Helsingin yliopisto, 2016)
    The concept of ecosystem services, wide-spread in academia and policy making, emphasizes societal and economic dependence on natural systems for, among others, provision of food, fibres and water, regulation of climate and soil, and contribution to spiritual and cultural values. Anthropogenic pressures driven by rapid economic development are, however, causing a disruption in the benefits that humans obtain from ecosystems. Several economic sectors both depend on and impact ecosystem services. There is therefore maturing expectation for the private sector involvement in environmental governance worldwide, as firms are increasingly motivated to pursue sustainability for financial or strategic opportunities. This dissertation is among the first to address the current research void on the interactions between industries and ecosystem services. The topic is analysed in the context of extensive plantation forestry in the emerging economy of China. The main aim of this work is to investigate if and how the ecosystem services narrative can contribute to further develop corporate sustainability agendas and practices. Based on the findings from this work, ecosystem services research can provide insights and tools to pursue a more comprehensive and holistic acknowledgement of and response to interlinked ecological and social issues in corporate sustainability. For instance it can enable the understanding of company impacts and dependencies on ecosystems, and associated business risks and opportunities; deepen the analysis of company stakeholders perspectives and expectations; contribute to the design of sustainability-oriented practices; and enrich corporate disclosure practices. Further operationalisation of the ecosystem services approach into corporate sustainability would require a more systematic assessment and comparison of the relations between relevant business sectors and ecosystems, the analysis of global-local trade-offs, the internalizations of concepts such as ecological limits and ecological resilience, and the elaboration of suitable corporate and industrial response strategies. Keywords: China; Corporate sustainability; Ecosystem services; Forest sector; Plantations.
  • Rytioja, Johanna (Helsingin yliopisto, 2016)
    Basidiomycete white rot fungi are wood-rotting species and their impact to the global carbon cycle is significant. White rot fungi are capable of degrading all the polymeric cell wall components of the plant biomass from polysaccharides, cellulose, hemicelluloses and pectin, to the aromatic heteropolymer lignin. This is due to their ability to produce diverse set of extracellular enzymes that degrade or modify the plant cell wall concomitantly releasing carbon. Research on plant-biomass-degrading fungi has concentrated on isolation and characterization of enzymes especially from the ascomycete fungi for biotechnological applications, such as bioenergy, food processing and waste treatment. More recently genomic studies have opened the reservoir of the plant-biomass-degrading potential of basidiomycete fungi including wood-rotting, litter-decomposing, plant-pathogenic and ectomycorrhizal species. Dichomitus squalens is a white-rot fungus, which colonises softwood and is able to efficiently degrade lignin and cellulose. Previously, intensive studies on white rot fungi have been focused on lignin degradation by oxidative enzymes. The aim of this study was to analyse the potential of the plant-cell-wall-modifying enzymes of D. squalens. Plant biomass degradation by D. squalens was studied at different levels from gene expression to enzyme production. The focus was to dissect the overall degradation of plant biomass polymers, especially cellulose degrading enzymes of D. squalens. The cellulose degradation by D. squalens was studied at the transcript level during growth on spruce wood sticks and in microcrystalline cellulose-containing liquid medium. Selected cellulases and oxidoreductases, which putatively act on cellulose were expressed simultaneously on spruce, the natural substrate of the fungus, and microcrystalline cellulose in time- and substrate-dependent manner. To clarify the adaptation of D. squalens to different plant biomass, the transcriptome and secretome of the fungus were studied in different wood and non-woody substrates. The study confirmed that lignin degradation occurs at the initial stage of growth and D. squalens has retained the diverse enzyme set both for the degradation of wood and non-woody plant biomass. The cellobiohydrolases (CBHs) and cellobiose dehydrogenase of D. squalens were biochemically characterized. In hydrolysis of different plant-derived biomasses, CBHs released reducing sugars alone and in combination with oxidative laccase enzyme. The study shows that D. squalens encodes a complete enzymatic repertoire for plant biomass degradation. In addition, the data emphasise the role of oxidoreductases in the white rot fungal degradation of cellulose and other plant cell wall polymers. Results suggest that white rot fungal plant cell wall converting enzymes are promising candidates in the biotechnological applications using plant biomass.
  • Liu, Jiao (Helsingin yliopisto, 2016)
    The aim of the thesis was to investigate the interaction between sarcoplasmic proteins and myofibrillar proteins, considering the effects on the loss of water-holding in mild heat induced denaturation such as occurring in pale, soft and exudative (PSE) condition. Porcine longissimus thoracis et lumborum muscles were incubated at temperature 0, 10, 20, 30 or 40 ˚C to 6 h post mortem. Incubation at 40 ˚C reduced the water-holding of meat compared to the lower temperatures (P < 0.001). SDS-PAGE and Western blot analyses indicated that glycogen phosphorylase and creatine kinase precipitated with the myofilaments, which was already accomplished at 6 h post mortem. Substantial meat tenderization was measured after incubation at 40 ˚C, but with less activity of extracted μ- and m- calpains compared to lower temperatures (P < 0.001), which suggests that an early activation of calpains at the highest incubation temperature could have been the reason for the tenderization. Surface hydrophobicity of myofilanments was higher after the pre-rigor incubation at 40 ˚C compared to lower temperatures (P < 0.001). Less myosin subfragment-1 (S1) units were released by chymotryptic cleavage simultaneously with the loss of Ca2+ ATPase activity after incubation at 40 ˚C than at lower incubation temperatures (P < 0.001). The results suggest that the high temperature incubation induce microstructural alterations on the myosin head (S1) region, which may in turn have been related to the loss of water-holding. The roles of the denaturation of sarcoplasmic proteins and myofibrillar proteins were compared. Sarcoplasm not-incubated or incubated at 44 ˚C were mixed with protein-depleted sarcoplasm in different rations and the mixtures were combined with myofibrils and subjected to PSE-like condition pH 5.6/44 ˚C for 1 h . Water-holding was the poorest without the incubated sarcoplasmic proteins. Precipitated sarcoplasmic proteins shrank the myofilamental lattice spacing by 6.3%, compared to protein-free sarcoplasm, during post-rigor incubation at 44 ˚C, shown by X-ray diffraction. These results challenge the current understanding of the role of the denaturation of different proteins in water-holding, and therefore, a new hypothesis is proposed in this thesis: 1) in the intramyofibrillar space, the presence of precipitating sarcoplasmic proteins is associated with the filamental lattice compression that expels water; 2) in the space outside the myofibrils (intermyofibrillar space) within fiber and up to the extracellular space, the coagulated sarcoplasmic proteins form a network that traps water expelled from the intramyofibrillar space.
  • Mousavi, Seyed Abdollah (Unigrafia, 2016)
    ABSTRACT Studies of the taxonomy of bacteria were initiated in the last quarter of the 19th century when bacteria were classified in six genera placed in four tribes based on their morphological appearance. Since then the taxonomy of bacteria has been revolutionized several times. At present, 30 phyla belong to the domain Bacteria , which includes over 9600 species. Unlike many eukaryotes, bacteria lack complex morphological characters and practically phylogenetically informative fossils. It is partly due to these reasons that bacterial taxonomy is complicated. Due to the improvement of methods to obtain sequence level characters plus new methods for their analyses, the taxonomy of bacteria has also been improved. However, there is still no official classification of prokaryotes. Biological nitrogen fixation (BNF) is a process in which bacteria reduce inert nitrogen gas to biologically useful ammonia. The symbiotic interaction between rhizobia and legumes (Fabaceae or Leguminosae) is important both in natural systems and in agriculture. Rhizobia is a general name for a group of bacteria that can enter symbiosis with legumes. Until 1982, all these were classified into one single bacterial genus, Rhizobium. The number of rhizobial genera increased to 17 by the year 2011, from which five genera, Rhizobium, Allorhizobium, Agrobacterium, Ensifer (syn. Sinorhizobium), and Shinella were accommodated in the family Rhizobiaceae. The genus Agrobacterium, a group of mostly pathogenic bacteria, was placed among the beneficial nitrogen-fixing bacteria (rhizobia) in the family Rhizobiaceae. That resulted in several taxonomic issues regarding the family Rhizobiaceae. The main nomenclatural issue regarding the genus Agrobacterium resulted from transferring this genus to the genus Rhizobium. Moreover, the phylogenetic position of the former nitrogen-fixing Rhizobium galegae complex was not clear. This group of bacteria was in previous studies clustered with either Agrobacterium or Rhizobium or placed in a lineage separately from other genera of the family Rhizobiaceae. During the last decade, the number of the rhizobial species increased dramatically, especially in the genus Rhizobium. However, Rhizobium is an inappropriate genus name for some of the species assigned to the genus. To resolve some of the major taxonomic uncertainties of the family Rhizobiaceae, two separate multilocus sequencing analyses (MLSA) were performed. In the first study, an MLSA of 114 rhizobial strains was performed by using six housekeeping genes (atpD, glnA, glnII, recA, rpoB, and thrC). The first MLSA study was focusing on the phylogeny of the taxa belonging to the former Rhizobium galegae complex and the genus Agrobacterium. In the second MLSA, a total of 100 strains representing 81 species of the family Rhizobiaceae were studied using four housekeeping genes namely 16S rRNA, atpD, recA, and rpoB. Based on these results, we proposed delineation of two new genera, Neorhizobium gen. nov. and Pararhizobium gen. nov., and 16 new species combinations, Neorhizobium galegae comb. nov., Neorhizobium huautlense comb. nov., Neorhizobium alkalisoli comb. nov., Agrobacterium nepotum comb. nov., Agrobacterium pusense comb. nov., Agrobacterium skierniewicense comb. nov., Allorhizobium vitis comb. nov., Allorhizobium taibaishanense comb. nov., Allorhizobium paknamense comb. nov., Allorhizobium oryzae comb. nov., Allorhizobium pseudoryzae comb. nov., Allorhizobium borbori comb. nov., Pararhizobium giardinii comb. nov., Pararhizobium capsulatum comb. nov., Pararhizobium herbae comb. nov., and Pararhizobium sphaerophysae comb. nov. (Paper I and II). A total of 159 bacterial strains were isolated from the nodules of the Chinese specimens of the plant genus Glycyrrhiza L. The results of the study showed that 29 true symbiotic strains belong to the genus Mesorhizobium. To estimate the phylogenetic position of the 29 isolates an MLSA was performed for 59 mesorhizobial strains by using three housekeeping genes 16S rRNA, recA, and rpoB. Moreover, the phylogeny of three symbiotic genes (nodA, nodC, and nifH) of these 59 mesorhizobial strains was investigated. The results of MLSA showed that 21 test strains belong to the species M. tianshanense, M. gobiense, M. temperatum, M. muleiense, M. amorphae, M. alhagi, and M. camelthorni, whereas eight test strains might belong to a novel species of Mesorhizobium. The results of the analyses of accessory genes in this study showed that the mesorhizobial strains isolated from the plant genus Glycyrrhiza have probably acquired some genetic material from other rhizobia co-evolving with Glycyrrhiza and other legumes (Paper III).
  • Vehkaoja, Mia (Hansaprint Oy, 2016)
    Wetland and deadwood loss have had a profound effect on boreal aquatic and terrestrial ecosystems and their biodiversity. Deadwood-dependent species are one of the most endangered organism groups in the world, while amphibians on the other hand excellently represent the ecological state of wetlands. The boreal region contains a large proportion of the world s wetlands, which have undergone two major alterations during the last 500 years: first the extirpation of beavers and secondly draining during the 20th century. Beavers are well-known ecosystem engineers of the Northern Hemisphere. They modify their surroundings by damming water systems. Damming raises flood waters into the surrounding riparian forest and changes environmental conditions both on land and in water. Ecosystem processes are altered when beavers turn a lotic water system into a lentic one, but the alteration is also evident when beavers modify initially lentic water systems. Organic matter and nutrients are transferred into a wetland from beaver-felled trees and vegetation killed by flooding. The amount of dissolved organic carbon increases during the first three impoundment years, which enhances the growth of aquatic vegetation and the abundance of phyto- and zooplankton, thereby also increasing invertebrate abundances. Luxuriant vegetation and ample plankton and invertebrate populations facilitate frogs, which become abundant in beaver wetlands. The moor frog in particular favours beaver-created wetlands. Flooding and beavers kill trees, producing high amounts of deadwood. The riparian forests of beaver wetlands include much higher deadwood levels than wetlands without beavers. Increased deadwood creates substrate resources for deadwood-dependent species. Snags are a typical deadwood type in beaver wetlands. Calicioids are deadwood-dependent species particularly specialised in inhabiting standing deadwood. The comeback of beavers has aided the restoration of wetlands and deadwood. Beaver wetlands can be seen as carbon and biodiversity hot spots that increase the heterogeneity and hydraulic connectivity of the boreal landscape.
  • Muziasari, Windi (Helsingin yliopisto, 2016)
    Antibiotic resistance has become a serious threat to the efficacy of antibiotics used in human and veterinary medicine. Understanding the abundance and prevalence of antibiotic resistance genes (ARGs) in the environmental resistome is important for maintaining the efficacy of antibiotics and predicting a risk of the ARGs spreading in the environment and moving into previously non-resistant bacteria, including human pathogens. Fish farms are an environmental reservoir of ARGs due to the treatment of fish with antibiotics that also are important for human medicine. The two main topics of this thesis are (1) determining the abundance and diversity of ARGs and mobile elements in sediments impacted by fish farming and (2) investigating the major source of ARGs in the farm sediments in the Northern Baltic Sea. In addition, correlations between ARGs and mobile elements were examined to estimate the potential risk of ARG mobilization in the environment. This study employed a high-throughput qPCR array, which permits quantifying hundreds of ARGs and genes associated with mobile elements in the environmental resistome in a single experiment. Fish farming impacts the composition of ARGs in sediments below fish farms in the Northern Baltic Sea. However, the impact is local and mostly limited to enrichment of ARGs associated with antibiotics used at the farms. In the current conditions, the risk of ARG spread from the farm sediments to the surrounding sediments is low in the Northern Baltic Sea. However, the enriched ARGs persist in the farm sediments during the 6-year observations even when the selection pressure of the antibiotics is negligible. Moreover, significant correlations between mobile elements and ARGs may imply the persistence of certain ARGs in the fish farming environments and their potential for mobilizing the ARGs to other bacteria including pathogens. The persistence of ARGs at the farm facilities is a threat to the efficacy of the antibiotics against fish diseases, potentially leading to fish production losses. We provide indirect evidence suggesting that certain ARGs are being constantly introduced by feces of the farmed fish into the sediments below the fish farms. Further studies could focus on investigating the development of ARGs in juvenile fish before they are introduced into the Baltic Sea open-cage farms. We conclude that a high throughput qPCR array is a powerful tool that provides unprecedented insights into the ARG composition in the environmental resistome associated with fish farming.
  • Besong-Ndika, Jane E. (Helsingin yliopisto, 2016)
    The present study intended to identify new strategies for the selective presentation of biocatalyst on the surface of viral nanoparticles with potential application in biosensor technology or protein chips. Potyviruses were chosen as model nano-scaffolds for biocatalysts. Potyviruses are the largest genus in the family Potyviridae and cause significant plant damage. They form flexible rod-shaped capsids surrounding a single stranded positive sense RNA molecule. The molecular events leading to the specific selection and encapsidation of potyviral RNA are unknown. To better exploit the potential of these viruses as nano-carriers, the first step in this study was to look into their in vivo RNA encapsidation process. Earlier studies showed that Potato virus A (PVA) coat protein (CP) interferes with viral RNA translation when provided in excess in trans and it was suggested this could occur to initiate viral RNA encapsidation. In this follow up study, we used the ago-infiltration approach for the transient expression of full length, truncated or mutated viral RNAs with wild type CP (CPwt) and showed that this inhibition is mediated by co-translational CP-CP interactions occurring between two CP populations, produced in trans and in cis. Because CP inhibited translation of the entire viral genome and virus particles were formed (which were less abundant and appeared latter than during normal infection), it was assumed that the CP acted during this inhibition process to specifically recruit viral RNA for encapsidation. In line with previously published in vitro assembly studies, we propose a mechanism through which viral RNA encapsidation is initiated through co-translational CP-CP interactions. The second part of this work entailed the investigation of novel approaches for organizing biocatalyst on virus platforms. The aim was to be able to control the display of enzymes on virus surfaces while maximizing channelling of reaction intermediates. Three strategies were investigated: the first involved the use of specific PVA CP binding peptides selected by phage display, the second involved the use of heterodimeric leucine zippers and the last involved the use of an antibody binding peptide, the z33 peptide, from Staphylococcus aureus. The first two strategies were unsuccessful. On the other hand, the z33 strategy enabled an 87 % occupancy of accessible sites on the potyvirus particles by the enzyme. To further test the potential of potyviruses as multi-enzyme nano-carriers, two enzymes, 4-coumarate:coenzyme A ligase (4CL2) and stilbene synthase (STS), catalyzing consecutive steps in resveratrol synthetic pathway were employed as model biocatalysts. The z33-peptide was fused to the N-terminus of these enzymes, z4CL2His and zSTSHis and a chimera-protein, z4CL2::STSHis was also generated by the genetic fusion of both enzymes. All enzymes were active and resveratrol was synthesized from both mono-enzymes and the protein chimera either in solution or adsorbed on potyvirus particles. The latter was illustrated by trapping the mono-enzymes or the protein chimera from clarified soluble E. coli cell lysates on to the surface of potyvirus particles immobilized on the surface of a polypropylene tube. This strategy brings together a bottom-up and top down approach for designing virus based nano-materials and offers a cost effective and efficient way to co-immobilize and purify enzymes.
  • Rommi, Katariina (VTT Technical Research Centre of Finland Ltd, 2016)
    New protein sources are needed to fulfil the growing global demand for food protein. The co-stream from cold pressing of rapeseed oil, press cake, is a rich source of protein (32 26%) with good nutritional value. Several technologies based on alkaline or saline extraction have been developed for enrichment of rapeseed protein, but high energy and water consumption due to dilute conditions and multiple processing steps limit their sustainability and profitability. In the present study, enzyme-aided methods for extraction of protein from rapeseed cold-press cake were developed, and factors influencing protein extractability and properties of the obtained protein-rich fractions were elucidated. Pretreatments and carbohydrate-hydrolyzing enzyme treatment were used to facilitate extraction at reduced water content and without chemicals such as alkali or salt. Particularly a pectinase preparation with β-glucanase side activity enabled effective hydrolysis of rapeseed cell wall polysaccharides, increasing protein recovery by aqueous extraction. Similar improvement of protein extractability was, however, not achieved by mechanical cell wall disruption, suggesting that protein release was not to a major extent physically hindered by the residual cell structures in the press cake. Instead, enzyme treatment reduced the water holding capacity of the press cake and released hydrolysis products which are suggested to have enhanced the solubility of rapeseed protein during water extraction. At 10% solid content, enzyme-aided water extraction produced protein-enriched fractions with a similar yield and estimated production costs as conventional alkaline extraction (pH 10) and isoelectric precipitation. Techno-economic evaluation of different extraction schemes also suggested substantial reduction of energy costs when the extraction was carried out at 20% solid content. Due to the co-extraction of carbohydrates, enzyme-aided protein extraction was less selective than non-enzymatic alkaline extraction and isoelectric precipitation. On the other hand, carbohydrates are suggested to have improved the solubility and dispersion stability of protein extracts by electrostatic interactions. The results indicate that enzyme-aided fractionation methods are suitable for rapeseed protein production and may offer a techno-economically feasible alternative to alkaline or saline extraction. Additionally, protein hydrolyzates were extracted from dry-fractionated rapeseed press cake by proteolytic enzyme treatment. The hydrolyzates showed high inhibition of radical-induced oxidation in vitro, and their observed antioxidativity correlated with their protein and sinapic acid concentration. The hydrolyzates were also able to inhibit the myeloperoxidase and elastase enzymes involved in inflammation and skin aging, therefore having novel application potential as active ingredients or natural preservatives in skin care products.
  • Kylä-Nikkilä, Kari (Helsingin yliopisto, 2016)
    Mankind has exploited lactic acid bacteria for thousands of years. For most of this time, the use of these bacteria was based on tradition without deeper knowledge of the nature of these organisms. Nowadays, we have learned to know lactic acid bacteria and we are capable to genetically modify these organisms. In this thesis, methods to modify Lactobacillus helveticus bacterium to produce optically pure L(+)-lactic acid are introduced. Also, a method to immobilize lactic acid bacteria on unmodified cellulosic material is described. Lactic acid has two optical isomers: D(-)-lactic acid and L(+)-lactic acid. Most typically lactic acid is produced by microbial fermentation process. When using strains belonging to genus Lactobacillus in these fermentations, the produced lactic acid is most typically mixture of D(-)- and L(+)-lactic acid. In certain industrial applications, like that of the production of biodegradable plastic, pure L(+)-lactic acid is the preferred choice to be used as a raw material. In this work, two novel Lactobacillus helveticus strains were constructed for this purpose. As demonstrated by experiments, both these strains are potential producers of plastic grade L(+)-lactic acid. In many industrial-scale fermentation processes, it is beneficial to immobilize production strain on a solid carrier, whenever possible. From economical point of view, this kind of approach is very attractive especially if the immobilization is possible to carry out with minimal use of chemicals and processing steps. In this work Lactococcus lactis was genetically engineered to provide binding to chemically unmodified cellulosic carrier material. Putatively, by applying this method in an industrial-scale setup, it is possible to develop novel continuous fermentation processes.
  • Matthies, Brent (Helsingin yliopisto, 2016)
    The ecosystem service (ES) approach is a means of evaluating service value flows from ecosystems to humans for their well-being. The approach suggests that ecosystem functions are divided into categories according to the benefits derived and utilized by beneficiaries. The ES approach has become a tool for public and private decision-makers, driven by the need to more accurately incorporate environmental externalities into the value creation processes of economic actors. This research addresses two knowledge gaps within the ES literature. First, a service-centric approach to ES offerings is lacking, resulting in misuse of the appropriate concepts and terms when discussing their role in value networks and value creation. Second, there is limited available knowledge about how to efficiently internalize ES offerings within value networks. In the first article, a service-dominant value creation (SVC) framework, with supporting terms and concepts, was developed to guide interdisciplinary discussions about the role of ES offerings within value creation processes. The term value-in-impact was proposed as a means for discussing the trade-offs and impacts concerning ES offerings within those processes. The subsequent three articles addressed the following design aspects of Payment for Ecosystem Service (PES) schemes: (1) sensitivity to parameter inputs, (2) price volatility impacts on service providers, and (3) behavioural economic contributions. Consideration for trade-offs among ES offerings, and between ES offerings and economic objectives were also incorporated. The results indicated that the holistic accounting of ES indicators, to determine the optimal species mixtures, and uncorrelated ES price interactions, to determine the optimal allocation of forest for conservation, led to ecological and financial diversification benefits for service providers. Nudging service providers also led to more socially efficient ES provisioning. In each case, the proposed Ecosystem Service Expectation Value (ESEV) was used to more accurately describe the perpetual provisioning of multiple ES offerings on forestland.
  • Toivonen, Marjaana (Helsingin yliopisto, 2016)
    Environmental fallows are fields that aim to produce environmental benefits instead of agricultural products. In many European countries, the establishment and management of fallows is funded via agri-environmental programmes. This thesis focuses on the biodiversity benefits of environmental fallows in boreal farmland. I examined the impacts of different fallow types and landscape structure on the diversity and species composition of multiple taxa in fallows. I also aimed to evaluate what fallow types, and in what landscape context, are needed to contribute to different biodiversity objectives: the promotion of conservation concern species, overall species diversity or ecosystem services. Species richness and composition of the studied species groups differed substantially between fallow types, and landscape context further modified the value of fallows. Perennial fallows sown with meadow plants supported high plant species richness and bumblebee abundance. Old grassland fallows benefitted both butterflies in general, and butterflies and bumblebees with narrow niches and low dispersal capacities. The positive impacts were emphasized when long-term fallows were located in complex landscapes. High forest cover in the surrounding landscape increased plant species richness in perennial fallows. The breeding density of open farmland birds was highest in short-term meadow fallows in landscapes rich in perennial grasslands. Foraging edge birds preferred short-term meadow fallows in open landscapes and long-term grassland fallows in forested landscapes. Vegetation of annual fallow types game fields and landscape fields differed considerably from perennial fallows and other non-crop biotopes, thus enhancing landscape heterogeneity. My results show that the biodiversity benefits of fallows can be enhanced by adapting fallows to the landscape context and to specific conservation objectives. If the objective is to support species of conservation concern, managing long-term fallows in complex landscapes rich in perennial grasslands is probably the best strategy. Overall biodiversity can also be enhanced in short-term fallows, especially if they are sown with diverse seed mixtures of species that are not too competitive in field conditions. Depending on the sown species, short-term fallows provide good possibilities to enhance landscape heterogeneity and promote ecosystem services. Future studies should consider the specific roles of forest and perennial grasslands in driving the effectiveness of agri-environment schemes. In addition, the impacts of agri-environment schemes, including fallows, on realized ecosystem services should be investigated.
  • Korhonen, Jaana (2016)
    International industrial competitiveness depends on many aspects. It can be based on cost advantages over international competitors, which are realized as higher market shares and increased trade flows in global markets. Competitiveness can also be improved by creating higher value through increased product quality and by means of sustainability. This places increasing strategic importance on scarcening natural resources and on how proactively environmental responsibility is perceived in the international forest sector in the future; as an additional cost or more as an opportunity of a high road to competitiveness? The goal of this dissertation is to analyze international competitiveness and its drivers from five different perspectives at the regional, country, and firm levels, with an emphasis on the pulp and paper industry. The empirical research problems of five individual research articles are approached by combining quantitative and qualitative data analyses. The time period from 1990 to 2030 was covered in the analyses. The results highlight the importance of forests, markets, and regulation in creating competitive advantages at different levels in the sector. The traditional forest sector factors such as resource availability and traditional economic factors such price competitiveness are going to play an important role also in the future. However, sustainability will become increasingly important for the value creation opportunities of industries. It is an opportunity for companies in their global value chains if the global environmental awareness and societal demand for sustainability continue to increase. Therefore, more responsible use of global forest resources can offer solutions to global sustainability challenges, and in the transition to a bioeconomy in which the forest industry plays a key role.