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Current climate change is based on growth of greenhouse gas emissions, which are mainly due to human activities. Activities related to the global food system are responsible for about fourth of the global greenhouse gas emissions. Thereby, the emissions of the food system, which are related to the products that it provides, should be decreased. Greenhouse gas emissions of products can be estimated and communicated by the indicator of carbon footprint, whereas reduced greenhouse gas emissions of the products’ users, resulting from the emission improvements related to the products, can be presented by the carbon handprint. The aim of this master thesis was to calculate the carbon footprint of a Finnish food business’ meat containing food product. In addition, the food product’s meat component was replaced with different meat alternatives in order to assess the carbon handprints, and to compare the carbon footprint and carbon handprint as information providers of climate impacts. The main method used in this thesis was life cycle assessment, while methodology of carbon handprint was used as an additional method. Life cycle assessment was used to assess the carbon footprint, and it was applied according to the ISO standards of 14040 and 14044. Primary data for the study was collected from the Finnish food business through interviews by phone and e-mail, while secondary data was gathered from different sources. The actual calculation process of the carbon footprint and carbon handprints were executed by using Excel. The carbon footprint of the studied food product was found to be 1,20 kgCO2eq/one packaged food product, while the handprints based on the meat alternatives were found to be 0,27-0,39 kgCO2eq/one packaged product. Carbon footprint and handprint were found to be different as communication tools of climate impacts. In addition, they were discovered to have their advantages and limitations depending on the chosen point of view.

Agroforestry, a widespread land-use in tropics and especially in tropical drylands, is gaining increasing attention due its carbon sequestration and storage potential. Majority of African countries acknowledge agroforestry as a national climate change mitigation and adaptation strategy. Despite the large extent of African drylands and the commonness and importance of agroforestry systems to dryland livelihoods, these systems are scarcely studied and research on dryland African agroforestry carbon stocks are few. The aim of the study was to compare carbon stocks of three land-uses: Vitellaria paradoxa dominated parkland (PL), improved agroforestry system (IA) and, as a control, abandoned land (AL), to study carbon allocation between and within the land-uses and to examine the variability of biomass estimates of different allometric equations used in carbon inventory in West African Sahel. Study was conducted in two villages in Yorosso, Southern Mali. Carbon stocks accounted were woody above- and belowground biomass, litter and top-soil organic carbon. Allometric equations and root-to-shoot ratios were used for woody biomass measurement. Comparison of biomass estimations of different allometric equations and root-to-shoot-ratios was conducted by using multiple equations for the dataset. Total system carbon stocks were 24.7 MgC haˉ¹, 29.9 MgC haˉ¹ and 42.2 MgC haˉ¹, for PL, AL and IA, respectively, with statistically significant difference between PL and IA. Top-soil organic carbon (SOC) was important carbon pool, accounting 34.8 % of total system carbon in PL and IA, and 49.6 % in AL. There were no statistically significant differences on the SOC/biomass C ratios between the land-uses. PL had lower SOC stocks than IA or AL, difference being statistically significant. The reason for lower SOC stock of PL could not be explained in this study. IA had larger woody biomass carbon stocks (27.0 MgC haˉ¹) than PL (15.5 MgC haˉ¹ ) and AL (14.4 MgC haˉ¹), but the difference was not statistically significant due to the similar density of large mature trees in all of the land-uses and partly due to the large woody biomass variation within the land-uses. In all of the land-uses, most of biomass carbon was stored in large mature trees and in two species: V. paradoxa and Parkia biglobosa. Large woody individuals had major impact on the land-use level carbon stocks. For carbon conservation, these individuals should be preserved and spared even during land-use change. Despite relatively large density, young trees and shrubs stored diminutive amount of carbon compared to mature trees. As the currently young planted trees in IA will grow and mature in the future, the woody biomass carbon stocks of the system will increase significantly. Lack of regeneration observed in PL threatens the sustainability of the system and its carbon stocks. Future carbon storage potential of AL depends on the regeneration potential of large tree species. Comparison of different allometric equations for tree biomass estimation revealed substantial variation. The choice of allometric equation used affects the obtained results, hampering the comparison of studies using different equations. Commonly used root-to-shoot ratios vary on their estimations, and most probably by underestimating root biomass. There is a clear need for specialised and standard carbon inventory methods for drylands and agroforestry systems.

Water interaction at cellular level has been investigated in Scots pine (Pinus sylvestris L.) sapwood section of acetylated and paraformaldehyde-treated woodblocks. Unmodified wood samples were used as reference samples. Acetyl group from acetic anhydride bounded to H of OH sorption site whereas paraformaldehyde bound to the sorption site and also create a cross-linking. Both mechanisms cause hindrance towards the accessibility of available sorption site but up to what extent which is unknown. With our designed approach, we can estimate the moisture uptake in both treatments. Knowledge of the cellular level changes is important to define wood physical properties. Wood is hygroscopic material which tend to reach to equilibrium moisture content. It causes dimensional instability and fungal degradation. The number of accessible OH sites correlates with wood’s ability to uptake moisture. Acetyl and methyl groups occupy the accessible sorption sites and limit the availability of free sites. Gravimetrical estimation of the available OH sites can relate to the effect of cross-linking and hindrance towards water molecules. Both modification methods reduced the equilibrium moisture content (EMC) and the sorption hysteresis. Maximum WPG of acetylation (17%) reduced 15.63% moisture content (MC). Maximum formalization WPG (7,5%) reduced 15.09% MC. Acetylation reduced water sorption through the relative humidity (RH) range 0-95%, whereas formalization reduced water sorption steadily, but only above 20% RH. This difference was caused by the cross-linking, which increased the stiffness of the cell wall polymers. The shape of sorption hysteresis was similar in all the samples. Still, formalization reached the maximum hysteresis at a lower point related to the other samples. Accessible sorption sites also reduced by modifications. Acetylated wood reduced the greatest amount of OH groups according to its high WPG value, 16%. The reduction of OH accessibility was steady with acetylation. In formalization, the reduction of accessible sorption sites was rapid and constant. With our developed method, we can precisely investigate the OH accessibility of both treatments, which can reveal the fundamental aspect of water uptake related to its structural changes at the cellular level.

The genetic and morphological diversity of viruses and more specifically membrane-containing bacteriophages (phages) with single-stranded DNA (ssDNA) genomes is largely unexplored. It can be difficult to detect evolutionary relationships of viruses using solely sequence-based methods due to their rapid sequence evolution. However, more distant evolutionary connections of viruses have been observed based on structure data. Here we introduce an icosahedral tailless ssDNA phage, Cellulophaga phage phi48:2, isolated from the Baltic Sea that has not been assigned to any virus family or taxa. Phage phi48:2 has been previously linked to the family Finnlakeviridae whose members are icosahedral, internal membrane-containing phages with circular ssDNA genomes. However, the presence of lipids in phi48:2 virion has not been studied. In this study, different buffer conditions were tested for infectivity and stability of phi48:2 allowing us to optimize the purification of the phage particles by rate zonal and equilibrium ultracentrifugation in sucrose. Solvent tests in chloroform and ether, as well as low buoyant density of the virion suggested the presence of lipids in the phi48:2 virion. Analysis of the phi48:2 lipids extracted from highly purified virions by thin-layer chromatography revealed that phi48:2 is a membrane-containing phage and acquires its lipids unselectively from its host bacterium Cellulophaga baltica. Lastly, cryogenic electron microscopy of the purified virions also proposed that lipids form a membrane vesicle under the capsid. Altogether our results show that phi48:2 is an icosahedral membrane-containing phage, thus connecting it further with FLiP, which is the sole member of family Finnlakeviridae. Moreover, FLiP and phi48:2 virions are both ~60 nm in diameter and showed some similarity in their major capsid protein sequences (~21% amino acid identity). To conclude, even though phi48:2 and FLiP share various similarities they cannot be placed within the same family due to the low similarity in their genome sequences. However, for now we can assume they are possible distant relatives. The diversity and abundancy of membrane-containing ssDNA phages is gradually starting to uncover and through their characterization and classification we might consequently understand better their significance in microbial ecology.

Cellular agriculture is a novel food production technology that utilizes tissue engineering techniques to culture muscle cells to make cultured meat, or microbes and fermenting to create proteins such as casein, albumin and collagen which can be processed to products similar to milk and egg white for example. This thesis aims to explore the challenges that cellular agriculture faces in terms of policy, politics and the society mainly in a Finnish context, but also observing EU regulations. These challenges were investigated by interviewing altogether 15 representatives of stakeholder groups, which are political parties, government administration, organizations of policy executioners, NGO’s, food-tech companies, -funds and research centres. The data from the interviews was transcribed and processed in Atlas.ti-software using the analysis of qualitative content -method. The processed data was then analysed using the analysis of a specialist interview -method. The study revealed that specialists agree that cellular agriculture products will follow EU Novel Food regulations, but that cellular agriculture might have to overcome some regulation-related challenges. Challenges might also arise from markets, consumers and competing with conventionally produced food. Some believed cellular agriculture to have a negative impact on the Finnish society in the form of eroding rural livelihoods, and that the production will be in the hands of large corporations. Many stated that they do not believe cellular agriculture will surpass conventional agriculture, but that it will become just another food innovation. Some believed cellular agriculture offers great possibilities in the form of more sustainable food production. Many of the statements of the interviewees reflected current events already underway in the cellular agriculture and alternative protein field. The challenges cellular agriculture will face are multifaceted, and more information is still needed, especially on the societal effects of cellular agriculture.

The use of plastics has remarkably increased during the last 50 years. Due to its multi-use possibilities, durability and low cost the use of plastics is expected to double within the next twenty years. Despite the many benefits of plastics, the negative impacts to the environment, such as marine plastic, have raised the public attention and accelerated the demand for legislative action. To respond to these challenges, the European Commission (EC) engaged in developing a set of policies, such as the action plan for circular economy in 2015 which aimed to reduce the use of plastics and to enhance the recycling and reusing of plastics already in circulation. In 2018 the EC introduced a set of revised directives regarding the extended producer responsibility (EPR). I wanted to understand how this revised EPR scheme would be implemented into national legislation, and how it would be confronted by organisations such as ones dealing with wood products. Additionally, I also mapped the potential managerial implications for stakeholders resulting from the implementation of the scheme. I operationalised Primmer's (2011) framework of institutional adaptation which builds on two complementary strands of literature; policy implementation and organisational adaptation. The two focal research questions that derived from the framework were: How did the involved actors recognise and perceive the challenges in 1) implementing and 2) adapting to the extension to the existing EPR scheme in the use of plastic packaging of wood products? The data were collected by conducting seven semi-structured interviews with representatives of stakeholder organisations. The insights were explored and reported from these data via the means of qualitative content analysis. Considering the complexity of policy and the diversity of organisations across Finland – and the European Union, legislators are in a rush to implement the new requirements of the directives into the national legislation. Based on my studies the involved actors recognised the various challenges in the implementation and adaptation processes. There were also expectations that the policy will drive learning and innovation among organisations. Currently, legislation is the major driving factor in the development of plastic recycling and EPR schemes can be a robust legislative tool in attaining the targets, when developed and maintained accordingly.

Globalization encourages migration all over the world. Dietary acculturation, the process of adopting the dietary practices of the host country, has become an interesting issue in community nutrition and nutritional anthropology. This is the first study on Chinese immigrants and dietary acculturation in Finland. In this study, the Koctürk model is used as conceptual framework which had showed its usefulness to structure the various foods and changes which may occur. The thesis aims to investigate whether any changes take place in the food habits of Chinese students after migration to Helsinki, Finland, as well as the food habits which are still maintained after migration. If changes or stability occur, the factors that are associated with the changes or stability are analyzed. Data were collected from 16 Chinese students who study in university of Helsinki, and have been staying in Finland at least 6 months. A tape-recorded interview was arranged, which included a questionnaire and an interview with semi-structured questions. After migration, several changes appeared in meal pattern, food choices and food preparation methods among Chinese students. Breakfast seemed to be the first meal to be “Westernized”. In accordance with the Koctürk model, the cultural importance of breakfast and lunch has diminished, and dinner became the most important meal. Weekend diet became more traditional than weekdays’ diet. Chinese participants still keep festival diet in certain Chinese festivals, and they also tried some typical Finnish festival foods, especially mämmi and glögi. Food choices changed among all food groups—staple, complementary and accessory foods. Of 37 foods listed on the questionnaire, the consumption frequency increased significantly for 14 Finnish style foods and decreased significantly for 7 Chinese style foods. The Chinese students also prepared foods more often by methods such as baking, adding cheese or butter/margarine to foods. The interviews revealed various factors influencing changes and stability: Chinese cultural beliefs, attitude, taste preference, stress, social relations, food cost, convenience, availability and perceived freshness of foods.

The shelf life of ESL milks and pasteurized creams is limited by bacterial spoilage. The current state of knowledge with respect to the diversity and activities of the spoilage microflora in these products is still limited. To date, studies on this subject are yet to be carried out in Finland. The aim of this study was to characterize the spoilage microorganisms found in ESL milks and pasteurised creams mainly produced in Finland. 10 ESL milks and 8 pasteurised cream packages were obtained from the Finnish retail market and were stored at 8?C, 15?C, room temperature and 30?C, respectively, until expiration. Total bacterial counts were evaluated and 31 bacterial isolates were selected. An attempt was made to characterize the bacterial isolates using rpoB and 16S rRNA partial gene sequence analyses. Psychrotrophic, spore-forming and spoilage features were also determined. Strain diversity was determined by rep-PCR profiling. Five selected isolates were subjected to metabolic profiling using the API50 CHB test. When growth was detected, total bacterial counts ranged from 2.67 to 3.74 and 2.54 to 8.98 log units in cream and ESL milk samples, respectively. Both ESL milks and cream samples were dominated by heat-resistant, spore-forming species of the Bacillus genera: the isolates were related to B. licheniformis. B. weihenstephanensis, B. safensis, B. kochii, B. pumilus, B. subtilis and B. anthracis. Intraspecies and intrasample strain diversity was very high. Isolates mainly displayed proteolytic and lipolytic activity. Psychrotrophic activity was high in the cream samples while most ESL milk isolates were mostly mesophilic. Tested isolates were non-lactose fermenters and had varying metabolic profiles. The study revealed that Finnish ESL milks and pasteurized creams are prone to spoilage by species of the Bacillus genera that have potential for lipolytic and proteolytic spoilage and some of which are considered toxigenic. There is wide intraspecies strain diversity responsible for the wide variability in metabolic, psychrotrophic and spoilage features. Phenotypic tests based on API50 CHB cannot be relied upon to make conclusions on taxonomy. Combining various methods is important for the comprehensive characterization of the bacterial isolates. Strategies to eliminate bacterial species of the Bacillus genera are important to prolong shelf life. However, intervention should be strain-specific to be effective. Large scale studies are required to confirm findings from this study.

Efficient utilization of renewable plant and crop based biomass is one of the main areas of study in industrial biotechnology. Roughly 20-30 % of all plant biomass consists of hemicellulose, a polymer composed of six carbon (hexose) and five carbon (pentose) sugars. This proves a challenge in utilizing all available plant biomass efficiently, since many micro-organisms, which for instance readily ferment glucose (a hexose) into ethanol, will not do so for pentose sugars. Alternative pathways for utilization of pentose sugars are being looked for. Characterization of the Caulobacter crescentus D-xylonate dehydratase (Cc XyDHT) was the aim of this study. Cc XyDHT belongs to the ILVD/EDD protein family, whose members incorporate an iron-sulfur (FeS) cluster into their protein structure coordinated by two to four cysteine amino acids. Removal of the cysteine ligands should disrupt the incorporation of the FeS cluster, and thus presumably the activity of the enzyme. Three cysteines in Cc XyDHT which could act as ligands for the FeS cluster had previously been identified by sequence alignment among the ILVD/EDD family. Accordingly, four single cysteine-to-serine mutants of the Cc XyDHT as expression plasmid constructs were designed, with a non-conserved cysteine residue selected as a control. The wild type and mutated Cc XyDHTs were produced in Escherichia coli and purified with affinity chromatography using Strep-tag. SDS-page and Western blotting with an anti-Strep-tag antibody were used to confirm that the expressed proteins were Cc XyDHTs. The mutations’ effects on the protein fold and to the presence of the FeS cluster were investigated with UV and circular dichroism spectroscopy. Cc XyDHT catalyzes the conversion of D-xylonate into 2-keto-3-deoxy-xylonate. A colorimetric assay using thiobarbituric acid (TBA) as the reactant was used to measure enzymatic activity. The pH and temperature optima, substrate specificity, and enzyme kinetics of the wild type Cc XyDHT were determined. For the two best substrates, kcat/Km = 1220 mM/min for D-xylonate and kcat/Km = 1160 mM/min for D-gluconate were found. All three conserved mutations were found to reduce enzymatic activity more than 99 % with these substrates. Depending on which cysteine was disrupted, differences in the kinetic constants between D-xylonate and D-gluconate were found. The non-conserved mutation reduced activity by approx. 40 %. The spectroscopic results indicate that the three conserved mutants lacked the FeS cluster, while the non-conserved mutant still incorporated it. It can be concluded that the three conserved cysteines are involved in coordinating the FeS cluster, which itself plays an important role in the catalytic activity of Cc XyDHT. These findings should be helpful for follow-up studies in biotechnological application of pentose sugars acids and their derivatives.

Cell walls (CWs) are the safeguards of plant cells and have a crucial role in controlling cell integrity and plant-environment interactions. Perception of cell wall damage (CWD) results in activation of signaling pathways leading to activation of plant defiance responses. Previous research utilizing murus1 GDP-L-fucose deficient mutant has shown the role of GDP-L-fucose biosynthesis in controlling the structure and integrity of the CWs. Here, we investigated whether phenotypical consequences provoked by the lack of GDP-L-fucose, observed in mutants lacking MURUS1 can be suppressed by blocking signal transduction pathways involving THESEUS1 (THE1) receptor-like kinase or WALL-ASSOCIATED KINASE 2 (WAK2)- MAP KINASE 6 (MPK6) signaling module involved in CWD responses. For this, mur1 the1 and mur1 mpk6 double mutants were generated and analyzed. We found that the phenotypes of double mutants closely resemble that of mur1 mutants, indicating that the morphological consequences of GDP-L-fucose deficiency develop independently of THE1 and MPK6 signaling. Further, we aimed to investigate whether GDP-4-keto-6-deoxymannose-3,5-epimerase-4-reductases GER1 and GER2 controlling the final step of GDP-L-fucose synthesis are functionally redundant. Due to the inability of generating ger1 ger2 double mutants, we have applied the artificial microRNA (amiRNA) strategy to generate ger1 ger2 amiRNA knockdown plants. We found that these knockdown plants exhibit severe developmental growth defects similar to those observed in plants impaired in import of GDP-L-fucose into the Golgi apparatus and these growth defects exceeded those observed in plants lacking MUR1. Therefore, we have concluded that GER1 and GER2 are functionally redundant.