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The purpose of this thesis was to study the antibiotic perturbations in bacterial populations. Perturbations are common in ecosystems and they can change the composition and functionality of a community substantially. The response of a community is governed by ecological and evolutionary factors: perturbations change the competitive ability of species in the community, but rapid evolution can further affect species fate. This thesis focuses more on the ecological effects. Understanding the community response to a disturbance would be interesting both from a general point of view and from the more practical approach of understanding natural communities under perturbations caused by antibiotics but also, for example, by climate change or chemicals. Thus far, most studies have been performed in one- or two-species systems, not taking into account the effects communities have on the fate of a single species. To study antibiotic perturbations, a multi-species bacterial community was exposed to a streptomycin pulse of three different levels concentrations. Changes in community composition were studied in the end of the pulse (ecological resistance) and after a recovery period (resilience) from the antibiotic perturbation comparing to the pre-perturbed communities. Further, the presence of species flow was manipulated to examine if it could enhance community resistance and resilience. Based on the analysis, even low antibiotic concentrations can have a long-lasting effect on community composition, but the magnitude of the effect is dependent on the concentration. Community diversity was recovered better than the composition, especially after the weaker perturbations. Species flow aids in community recovery but does not affect resistance. The results were relatively reproducible between replicate communities, and species traits steered the species fate in, pointing to deterministic ecological processes driving the community response. However, repeatability decreased in communities perturbed with the highest antibiotic concentration, which could point to evolution.

Lactic acid bacteria have a long history of use in food industry due to their favorable metabolic properties and health benefits for human health. Therefore, they are generally recognized as safe (GRAS) by FDA (U.S Food and Drug Administration) and have QPS (Qualified Presumption of Safety) status granted by EFSA (European Food Safety Authority). Nowadays, antimicrobial resistance (AMR) is a serious global risk and due to the increasing AMRs, more and more microbial infections have become more difficult to treat with antibiotics. AMR has mainly been of concern in relation to pathogenic microbes. However, since fermented foods are favorable environments for AMR gene transfer it should also be considered in the context of beneficial bacteria and their potential to spread AMR genes into pathogenic microbes. The aim of this study was to determine antibiotic susceptibilities of Lactobacillus plantarum, Lactobacillus rhamnosus, Leuconostoc sp. and Weissella sp. strains by E-test method and to detect selected specific antibiotic resistance genes by PCR. In addition, the goal was to define new cut-off values for Weissella strains since, so far, these have not been defined by EFSA. Antibiotic susceptibilities were determined against eight antibiotics: ampicillin, chloramphenicol, clindamycin, erythromycin, gentamicin, kanamycin, streptomycin and tetracycline. The detected AMR genes were blaZ, mecA, cat, lnuA, tetK and tetM. Most of the determined strains were observed to exhibit a notable resistance to kanamycin. Several Leuconostoc sp. and L. rhamnosus strains showed also resistance to chloramphenicol. Interestingly, one L. rhamnosus strain was observed to exhibit multiresistance to chloramphenicol and clindamycin. Moreover, 48% Leuconostoc strains had higher MIC value for streptomycin than the cut-off value defined by EFSA. Any of the selected AMR genes were not detected even though a notable resistance during the phenotypic testing was observed. However, this might be explained by the small amount of detected AMR genes. The results obtained in the present study provided more information about the antibiotic susceptibility and the safety of L. plantarum, L. rhamnosus, Leuconostoc sp. and Weissella sp. strains. Moreover, new cut-off values were proposed for Weissella sp. strains.

The literature review illustrated the negative impacts of mold spoilage in baked goods and the significance of lactic acid fermentation used to prevent mold growth, with a special emphasis on the mechanism of antifungal metabolites produced by lactic acid bacteria. A brief introduction of the raw materials (faba bean and pearl millet) was also involved. The aim of this study is to explore the potential of different strains of lactic acid bacteria producing antifungal compounds during faba bean and pearl millet fermentation, to facilitate their application in baked foods with extended shelf-life. Different species of lactic acid bacteria isolated from faba bean and pearl millet in previous studies were used singly as a starter for sourdough fermentation. Antifungal assays were carried out on target molds and selected sourdoughs showing antifungal activity were analyzed to assess the nature of antifungal compounds (e.g. organic acids and proteinaceous compounds). All of the water-soluble extracts from sourdoughs were able to inhibit the growth of the indicator molds P. paneum and P. albocoremium, but not A. niger. This was in agreement with previous findings, showing that sensibility towards different antifungal compounds is not identical across different molds. The concentration of organic acids and the potential proteinaceous nature of the most active extracts was also established. It was hypothesized that the organic acids produced during fermentation can act in synergy with proteinaceous compounds and could contribute to the antifungal activity of faba bean sourdough fermented with L. sakei F1410 and L. mesenteroides I21 and of pearl millet sourdoughs fermented with P. pentosaceus A133 and A1231. Furthermore, small molecular peptides generated possibly through proteolysis of proteins in faba bean sourdough fermented with P. pentosaceus I02 and in pearl millet sourdough fermented with L. palantarum A103 could be responsible for the antifungal effect.

Alzheimer’s disease (AD) is the seventh leading cause of death worldwide. One hallmark of AD includes the amyloid beta (Aβ1-42) peptide that accumulates into oligomers, fibrils, and plaques. Aβ1-42 has been shown to be structurally and functionally similar to antimicrobial peptides (AMPs). Publications have reported that Borrelia burgdorferi can be found in the brain of AD patients. B. burgdorferi and B. garinii cause Lyme disease (LD). B. duttonii is responsible for relapsing fever (RF), a disease characterized by recurrent episodes of high fever. The aim of this research was to study whether synthetic Aβ1-42 binds to LD and RF Borrelia sp. and several bacterial molecules important for their virulence, and whether Borrelia sp. have evolved strategies to evade Aβ1-42-mediated killing. Binding of Aβ1-42 to B. burgdorferi, B. garinii and B. duttonii and several microbial molecules was studied by ELISA and immunoblotting. Bacterial culturing and microscopy were used to study survival, agglutination, and phagocytosis of Borrelia sp. in the presence of Aβ1-42 and microglia. In this research, Aβ1-42 was able to bind and agglutinate all of the three studied Borrelia sp. However, Aβ1-42 reduced the survival and increased the phagocytosis of B. duttonii. while B. burgdorferi and B. garinii were unaffected. In addition, potential Aβ1-42 binding molecules were detected from several bacterial species, including FhbA expressed by B. duttonii. In conclusion, this study suggests that some restricted species of bacteria may evade Aβ1-42 entrapment and thus may be involved in the ability of the species to invade the CNS that may trigger neuroinflammation related to AD.

Automatic measurement of temporally varying soil moisture content could result in benefits both in agriculture and other applications. Mainly due to the ease of automation only electrical methods are suitable for measuring the variability of temporal moisture content. Capacitance technology is one of the most suitable methods for this kind of purpose. When determining soil moisture content by dielectricity means one will face two main properties: soil permittivity and soil electrical conductivity. Moisture measurement is based mainly on the changes of soil permittivity. Instead, changes in the soil electrical conductivity typically hamper the accuracy of moisture measurements. The measurement accuracy can be improved, however, by increasing the measurement frequency. The aim of this study was to determine the impact of sensor’s physical geometry and measuring frequency to the reliability of measurement. Combination of two measurement frequencies and an additional measurement of soil resistance were also determined for improving the accuracy. This study was carried out as part of the SAFETOOL project which aims were to monitor and to develop measurement tools for measuring and monitoring the status of the environment in field conditions. The sampling volume of capacitive sensors was examined in both field and laboratory conditions. To stabilize the weather moisture measurements were done only in laboratory conditions. The study was divided into two parts: pre-study and main-study. During the main-study five different capacitive geometries and the measurement of soil resistance were examined. Capacitance was measured using three frequencies: 5,5, 70 and 95 MHz. A commercial EC-5 capacitance sensor (Decagon Devices, Pullman, WA, USA) was used as control. Measurements were carried out in containers of volume about 3 litres filled with fine sand. Moisture measurements were conducted with volumetric water contents of 5 %, 15 %, 25 % and 35 % while the electrical conductivity varied between 2 and 24. Changes in the physical geometry did not result in remarkable differences of accuracy. The measurement volumes were also similar within the variable geometries. The impact of changes in the electrical conductivity, or salinity, however, was significant. Measuring the resistance of the soil lead typically to better results. However, this could be due to relatively high soil electrical conductivity. While working within the framework of normal field conditions and the right calibration one might expect to get reliable moisture measurements with a capacitance moisture sensor.

The aim of this thesis was to validate the AOAC integrated total dietary fibre method (2011.25) for tomato. Additional purpose of this study was to update dietary fibre values in Finnish food composition database Fineli. The literature review focused on the background of dietary fibre analysis, method development and dietary fibre composition of vegetables. The method measures separately insoluble dietary fibre (IDF), dietary fibre soluble in water but precipitated in ethanol (SDFP) and dietary fibre soluble in water and not precipitated in ethanol (SDFS; oligosaccharides). The method includes a 16 hour starch hydrolyzing incubation that was presumed to stimulate enzyme activity in tomato. The effect of endogenous enzyme activity was examined with preliminary experiments, which included keeping the sample at room temperature before analysis, inactivation of enzymes with heat treatment and performing the analysis without incubation. Repeatability and reproducibility of the method were determined by analysing a pooled sample consisting of Finnish tomatoes. The amount of IDF was highest in samples prepared without incubation. In incubated and heat treated samples, and in samples kept at room temperature the amount of IDF was lower and the amount of SDFP was higher compared to the samples prepared without incubation. This was propably due to pectin depolymerisation and solubilisation by enzymes. Validation sample was prepared without heat treatment. Validation was performed with incubated samples, because standard deviation for non-incubated samples was markedly higher. The amount of TDF (total dietary fibre) in digested samples was 1.3 % (1.1 % IDF and 0.2 % SDFP). Oligosaccharides were found only in trace amounts. Repeatability of the method was 11 % (TDF), 13 % (IDF) and 23 % (SDFP). Reproducibility was 11 % (TDF), 12 % (IDF) and 17 % (SDFP). Repeatability and reproducibility were propably impaired by the inhomogeneity of the sample matrix. Uncertainty of the method was 26 %. The method was validated and proven to be fit for purpose.

In recent years, consumer interest for probiotic products has significantly grown due to their health benefits, however challenges regarding viability and controlled release of probiotic bacteria during their processing and storage still exist. Microencapsulation of probiotics by spray drying with a suitable protective material could alleviate these challenges. This research aims to assess the viability of utilizing wood hemicelluloses recovered from forest industry side-streams, specifically galactoglucomannans (GGM) and glucuronoxylans (GX), as protective agents for the probiotic strain Lacticaseibacillus rhamnosus GG (LGG) during spray drying. The study results were compared to those of maltodextrins, considering varying solid concentrations (15 and 20%) and inlet air drying temperatures (105 and 140 oC). Feed dispersion properties including viscosity, pH, particle diameter and physical stability were determined. The probiotic's viability pre- and post-spray drying was evaluated, alongside powder characterization for moisture content, water activity, particle size, morphology and structure. Results indicated that both GGM and GX effectively shield LGG from heat impact during spray drying, yielding microcapsule powders with desirable attributes such as amorphous structure and low water activity. High encapsulation efficiency (>90%) comparable to maltodextrins suggested hemicelluloses as sustainable alternatives for conventionally used wall materials. Inlet air temperature or solid concentration did not affect encapsulation efficiency of hemicelluloses. Probiotic counts met a recommended level for probiotic products, signifying potential applications in food and pharmaceuticals. Powder yield, which varied between 35 and 58%, was significantly influenced by the encapsulating material. Morphological studies demonstrated well-formed, spherical particles at a specific drying temperature. The study proposes the potential use of wood hemicelluloses for effective probiotic protection, offering new possibilities for synbiotic powder applications in diverse industries due to their prebiotic properties which have been well reported in literature. Despite promising results, long-term stability and process optimization to improve the process yield and achieve lower moisture content for the microcapsule powders require further investigation. Adjusting feed dispersion parameters and exploring varied concentrations of hemicelluloses could enhance product yield. Meanwhile, increasing outlet air temperature possibly reduces the moisture content. This research fosters sustainable development in the forest industry, presenting a novel avenue for natural functional ingredient production.

Furniture is one of the most important necessities in people’s daily life. The development of furniture industry can also be regarded as the progress of society. China is the world’s biggest furniture manufacturer and exporter. After the rapid development in past few decades, the production, technology and quality of furniture has already mature. However, the traditional marketing models are showing disadvantages. It is important for furniture companies to explore profitable marketing models to grasp the market demands and obtain competitive advantages. In recent years, China's e-commerce saw a rapid development and is being used in different sectors such as clothes, shoes, books and beauty products. E-commerce platform is based on the internet, and it decreases the costs and makes shopping more convenient without the limitations on space and time. Chinese Premier Li Keqiang first landed out “Internet Plus” strategy in his government work report in 2015. The aim of this strategy is to promote the transformation of traditional manufacturing industries by using cloud computing, big data and internet of things based on the e-commerce platform. As a new concept, researchers seldom mention the operation of the e-commerce based internet plus strategy in the furniture industry. To fill this gap, this study was based on the perspective of companies, making practical explanations on internet plus and analyzed its application in furniture industry. In the methodology part, the business model canvas was applied to make qualitative analysis on the industrial level. Case study was also adopted to give quantitative support with the market data. Conclusion and discussions raised suggestions for future development and further studies.

In Norway spruce (Picea abies L. Karst.) lignin forms a major part of the xylem cell walls and renders the tracheids water resistant while giving support to the cell walls and the whole tree trunk. In Norway spruce lignin is polymerized mainly from coniferyl alcohol but the origins of this monolignol are not known. In our study, we employed laser capture microdissection (LCMD) system to isolate ray parenchyma cells and xylem tracheids from thin (30-40 μm), tangential cryomicrotome sections of developing xylem of the spruce trunk. We wanted to analyse the monolignol biosynthesis pathway gene expression separately in these cell types. Our aim was to examine the possibility that coniferyl alcohol is produced in the tracheid cells, or whether also the neighboring cells (ray cells) contribute to the biosynthesis of monolignols during the lignification as has been confirmed in angiosperms before. Total RNA extracted from the collected material was used to perform low mRNA input sequencing on the Illumina HiSeq platform to identify transcripts potentially involved in monolignol biosynthesis and secretion. As a control material we used whole cryomicrotome sections containing both xylem tracheids and rays. Deep sequencing was performed to generate quantitative expression data within a particular cell type. Differential gene expression was conducted with a Chipster analysis software by using DESeq2. Altogether, 936 genes were differentially expressed between whole sections and ray cells, and 424 transcripts were more abundant in ray cells, while 512 transcripts were less abundant. Comparison between whole sections and xylem tracheids illustrated that 18 transcripts were more abundant in xylem tracheids and 275 transcripts were less abundant. Our study demonstrated the usefulness of LCMD combined with RNA-Seq to characterize gene expression in specific cell types.

With a land tenure structure dating back to the Mexican Revolution of 1910, Mexico is second only to Papua New Guinea in proportion of forest land under community ownership. While many communities have successfully formed community forestry enterprises (CFEs) producing value-added goods and generating income and social benefits for community members, many more remain minimally involved with forest management or do not harvest timber. As such, this study sought to collect and analyze the opinions and experiences of groups and individuals involved in the forest sector, with the aim of providing a greater understanding of the strengths and weaknesses of the Mexican forestry model, the most important factors facilitating or undermining the development of CFEs, and opportunities for the advancement of community forestry in the future. This study is based on semi-structured stakeholder interviews which were conducted in four states with members of both harvesting and non-harvesting communities, members of Mexico's National Forestry Commission (CONAFOR) and Secretariat of Environment and Natural Resources (SEMARNAT), various experts with ties to the forest sector, and foresters serving the communities interviewed. The results indicate that communities face a number of significant developmental challenges. Community organization was found to be an essential internal factor, and successful CFEs have in common a strong internal cohesion and collective decision making capacity, while failure is often linked to indecision, internal divisions, or corruption. Will and ability to invest in the CFE are also crucial, and sources suggested that communities are often impeded by their lack of 'entrepreneurial mentality' when it comes to investment. For those that are interested in investing in the CFE, lack of available capital is often problematic. In part because of these challenges the Mexican forest sector relies largely on obsolete practices and technology, resulting in elevated costs of production relative to foreign competitors, and foreign competition has taken a toll on the industry in Mexico. In some areas declining industrial consumption has made it more difficult for communities to find buyers for forest products and may limit future production potential. The quality of technical services available to the communities is another factor that is both critical and inconsistent, and the important role of private foresters in aiding CFE development was emphasized by a number of sources. Government intervention has also had an important impact on the sector and CONAFOR has played a key role in its development in recent years. On the other hand, forestry is a heavily regulated activity and there appears to be a consensus that regulations could or should be simplified. It was also suggested that government agencies may not have the resources to process the paperwork they demand in a timely manner. Overall, community forestry in Mexico represents an important and environmentally sustainable source of rural livelihoods, and a great deal of potential remains for the expansion of the sector. While some challenges facing CFEs may not have clear solutions, there are some steps that could be taken to improve conditions in the future. Technological advance will be critical if Mexico is to compete on international markets, and there is work to be done both in terms of finance and in promoting 'business mentalities' and investment. Likewise, a thriving forest industry may require strong policy support from the federal government and efforts to ensure that technical services available to communities are adequate. Finally, it will be important to evaluate the regulatory balance between environmental protection and development of the sector moving forward, to create conditions that are both sustainable and conducive to growth.