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Työn tarkoituksena oli pystyttää reaaliaikainen PCR-menetelmä enterohemorraagisten Escherichia coli (EHEC) seroryhmien O26, O55, O91, O111, O113, O145 ja O157 sekä H7-antigeenin ja virulenssigeenien stx1, stx2 ja hlyA nopeampaa havaitsemista varten. Työssä testattiin menetelmän soveltuvuutta EHEC-bakteerien havaitsemiseen 45 puhdasviljelmäkannan lisäksi myös seitsemästä sekaviljelmästä, joista yksi oli Nokian vesiepidemian vesinäyte. Puhdasviljelmäkannat ja kuusi muuta sekaviljelmää olivat peräisin sairaaloista vuosien 1996-2007 välisenä aikana lähetetyiltä sekaviljelmämaljoilta. EHEC-bakteerit kuuluvat suolistotulehduksia aiheuttaviin E. coli-bakteereihin. Ne ovat suolistotulehduksia aiheuttavista E. coli-ryhmistä tärkein elintarvikevälitteisten ripulien aiheuttaja Suomessa ja muissa länsimaissa. EHEC-bakteerit leviävät pääasiallisesti elintarvikkeiden ja juomaveden kautta, vaikkakin alkuperäinen kontaminaatio on aina saanut alkunsa ihmisen tai eläimen ulosteesta. EHEC-infektion voi saada jo 10–100 bakteerista ja sen onkin todettu tarttuneen ihmisestä toiseen. Bakteerin tärkein reservuaari on nautakarjan ja muiden märehtijöiden suolistossa. EHEC-infektioita tavataan yleensä n. 10–20 tapausta vuosittain Suomessa. Suomessa, kuin myös maailmanlaajuisesti, yleisin epidemioita aiheuttanut EHEC-kanta on tähän mennessä kuulunut O157:H7-serotyyppiin. Muita tärkeitä epidemioita aiheuttaneita O-seroryhmiä Suomessa ja muualla maailmalla ovat olleet seroryhmät O26, O103, O111 ja O145. EHEC-bakteeri aiheuttaa vesiripulia, mutta potilaat voivat kärsiä myös vatsakivuista ja oksentelusta. Osalla ihmisistä vesiripuli voi muuttua myös veriripuliksi (Hemorragic Colitis, HC). Jotkut voivat olla myös oireettomia kantajia. EHEC-bakteerin aiheuttama ripuli voi kehittyä hemolyyttis ureeminen oireyhtymä (haemoltyic uremic syndrome, HUS- jälkitaudiksi, jonka oireina ovat akuutit munuaisvaurioit, mikroangiopaattinen hemolyyttinen anemia ja trombosytopenia. Aikuisilla voi esiintyä myös HUS:n tromboottiseksi trombosytopeeniseksi purppuraksi (trombotic trombocytopenic purpura, TTP) kutsuttua muotoa. HUS:n riskiryhmään kuuluvat alle viisivuotiaat lapset ja vanhukset. EHEC-bakteerin aiheuttama tauti luokitellaan Suomessa yleisvaarallisiin tartuntatauteihin. EHEC-bakteerin virulenssitekijöihin lukeutuu shigatoksiinin tuottogeenien (stx1- ja stx2-geenit) lisäksi myös Enterohemolysiinin tuottogeeni (hly-geeni) ja LEE (Locus of Enterocyte Effacement)-patogeenisuus saareke, joka sisältää mm. tir- ja eae-geenit, jotka määräävät proteiineja, joiden välityksellä EHEC-bakteeri kiinnittyy suolen epiteeliin. Shigatoksiineja pidetään oireiden pääasiallisena aiheuttajana. Tässä työssä testattu reaaliaikainen PCR-menetelmä (Real-Time PCR) on uusimpia EHEC-bakteerin tunnistamiseen käytetyistä menetelmistä. Menetelmä hyödyntää fluoresoivia koettimia, jotka toimivat fluoresenssi resonanssilla eli energian siirtymisellä (Fluorescense Resonance Energy Transfer, FRET) kahden fluoresoivan leiman kesken. Menetelmä mahdollistaa PCR-tuotteen analysoimisen monistamisen yhteydessä ja vähentää analysoimisen aikana syntyvän kontaminaatioriskin lisäksi myös turvallisuusriskiä, kun tulosten visualisoinnissa ei tarvitse käyttää karsinogeenista Etidiumbromidia (EtBr). Tässä työssä menetelmällä saadut tulokset olivat toistettavia ja vastasivat aiemmin monialukkeisella PCRmenetelmällä ja agglutinaatiotekniikalla saatuja tuloksia. Sekaviljelmiä testatessa reaaliaikaisen PCR-menetelmän kanssa samanaikaisesti rinnakkain tehty monialukkeinen PCR-menetelmä antoi myös yhtenevät tulokset. Reaaliaikainen PCR-menetelmä osoittautui monialukkeista PCR-menetelmää ja agglutinaatiotekniikkaa huomattavasti nopeammaksi menetelmäksi, joka mahdollistaa nopeamman diagnoosin, joka on tärkeää HUS-jälkitautia sairastavien potilaiden hoidon kannalta.

Fungal ferulic acid esterases (FAEs) are important accessory enzymes that participate in degradation of plant cell wall hemicellulose in grasses, including cereals and many energy crops. They could be used to convert agricultural wastes into a variety of value-added products such as biofuel, feed and paper. In non-aqueous media, they have been shown to act as catalysts for enantioselective reactions. Putative faes are widespread in genomes of plant pathogenic and saprotrophic fungi. However, only few FAEs have been characterized in detail. Additionally, despite of their diverse biotechnological potential, fungal FAEs have not been produced recombinantly on a bioreactor scale, which is a necessary step for their commercial applications. The aim of the present study was recombinant production on a bioreactor scale and biochemical characterization of a putative FAE from Aspergillus terreus. The enzyme demonstrated a broad substrate profile and an excellent storage stability. Its catalytic activity was highest against methyl 3,4-dimethoxycinnamate, but the enzyme was also active against methyl ferulate. It preferred methoxy groups to hydroxyl groups on the substrate’s phenyl ring, while shortening of the aliphatic side chain diminished the activity. The enzyme was observed to be fully stable at 37 °C for 1 h, and it demonstrated thermal activation at the same temperature. At 45 ˚C, it retained 75 % of its initial activity for 1 h. McIlvaine’s buffer was observed to increase the activity by 85 % compared to the standardly used MOPS buffer. The results of this study have contributed to the biochemical knowledge of fungal FAEs and elucidated their substrate preferences.

α-Galactosides (raffinose, stachyose, verbascose) are antinutritional factors found in pea and faba bean, that cause digestive issues for some people. Reducing the amount of α-galactosides could increase the consumption legumes. The objectives of the research were to decrease the amount of α-galactosides in pea protein concentrate (PPC) and faba bean protein concentrate (FBPC) and produce a low-FODMAP yoghurt analogue. α-Galactosides were reduced using two α-galactosidase enzymes, α-galactosidase A (two doses) and α-galactosidase B (one dose). A low-FODMAP yoghurt analogue was produced from PPC with α-galactosidase A added, and possible changes in viscosity measured. The change in the amount of α-galactosides was determined with the Megazyme raffinose/sucrose/glucose kit. α-Galactosides were completely eliminated with the bigger dose of α-galactosidase A. Differences were observed in the α-galactosidase treatment samples treated with the different enzymes and doses. FBPC has more verbascose than PPC which takes the longest time to hydrolyse (compared to stachyose and raffinose) due to the exoglycosidase action of the enzyme. It could be the reason to differences in reduction of α-galactosides in FBPC and PPC. The bigger dose of α-galactosidase A reduced α-galactosides similarly in FBPC and PPC after six hours but differences in the reduction of α-galactosides were observed in the other two doses in FBPC and PPC. A low-FODMAP yoghurt analogue with no changes in structure in terms of viscosity between the α-galactosidase treated and control samples was seen.

While export of non-timber forest products (NTFPs) has been promoted as a sustainable development strategy, the literature suggests that local and regional markets are also potentially important, not only for producers but also for traders and consumers (Shackleton et al. 2007). For producers, regional markets are thought to offer more accessible and more stable markets, while for traders, these markets offer employment, and for consumers, reasonably priced, diverse, fresh food. Consumption habits are changing in developing countries primarily due to urbanization and commercialized food systems as described by Johns and Maundu (2006). One result is the so-called “nutrition transition,” in which people adopt diets that are higher in energy (more added sugar and fat) but have less nutritional quality (Popkin, 2004). In this context, Johns and Sthapit (2004) argue that it should be a policy priority to promote a diverse diet including a lot of indigenous foods (fruits, vegetables and whole grain products) and a proper amount of animal products. In addition to their potential dietary contributions, forests also offer a diversity of traditional medicinal plants. Many people rely on these plants as a health care option because they are cheap, efficient and have cultural meaning. Medicinal plants are important for both the rural and urban poor in the Brazilian Amazon where the healthcare system is weak and unemployment is increasing (Shanley & Luz, 2003). In this thesis, I characterize the market for NTFPs in a major regional market in the Brazilian Amazon (the city of Belém), drawing on a survey of consumers in 2006 through 2009 (overall sample n=2635 consumers) that focused on seven popular NTFPs native to the area: a?ai palm fruit, medicinal oils (andiroba and copaiba), fruits (piquía, uxí, bacuri), and Brazil nut. In the first section, I describe who is buying NTFPs and identify trends in consumption across the four years of the survey. In the second section, I develop a market segmentation analysis, identifying, characterizing, and describing trends among different types of NTFP consumers. The market segments are identified based on two-step cluster analysis in SPSS. The results confirm that people in Belém use a wide variety of NTFPs, with fruits being the most commonly consumed. The seven focal NTFPs were popular during the study period, with over 95% of respondents reporting use of at least one of these products. However, the people who use NTFPs are not necessarily aware that they are consuming products from the native forest: according to the cluster analysis, half of the consumers fall into market segments that either do not consider themselves as NTFP consumers or are not aware that they consume NTFPs. These segments are comprised of people with less education and lower income, more females, and more long-term urban residents including natives of Belém. The other consumer segments, characterized by higher income and education and more recent migration to Belém, have greater awareness of NTFPs. If these segments grow, that could imply growth in demand for forest products. However, over the four years of the study, there was actually a decreasing trend in consumption of NTFPs, indicated by declining average counts of NTFPs and declining proportions of respondents who consume the focal products. This could be due to increasing prices, also observed in the data, which in turn may be due to the on-going forest degradation that is well-documented in the literature on the Brazilian Amazon.

The tRNA-derived fragments (tsRNAs) are known to play a role in protein translation and post-transcriptional regulation. Viruses exploit the cellular machinery of the host for their replication and therefore the formation of tRNA-derived fragments could be one mechanism utilized by the virus for completing the infection cycle. Virus-induced tRNA-derived fragments have so far been found to suppress the antiviral responses of the host or to favor viral protein translation. However, the biogenesis of tsRNAs, their virus specificity, as well as their putative regulatory roles during infection are still mainly unknown. Research into the roles of tsRNAs in viral infection has enormous potential to reveal novel regulatory functions of tsRNAs and shed light on the mechanisms which viruses utilize to hijack the cellular translation machinery. This Master’s thesis project aimed to investigate the possible regulatory role and the origin of infection-induced tRNA-fragments in Shewanella glacialimarina TZS-4T. S. glacialimarina was infected with Shewanella phage isolate 1/4 and total RNA was isolated from culture samples collected at different timepoints after infection. Additionally, to assess the specificity of the phenomena, S. frigidimarina and S. baltica, two evolutionary close relatives of S. glacialimarina, were also infected with Shewanella phage isolate 1/4. The formation of fragments was found to be dynamic and specific to S. glacialimarina. The observed fragments were further purified from the total RNA and sequenced using an adapted protocol for sequencing library preparation to identify the origin of the fragments. As a result of this thesis, the adapted protocol was further optimized for the fragment isolation, yet the full identification of the sequences was not achieved within the timeframe of this project.

Kiinnostus rehumaissin (Zea mays L.) viljelyä kohtaan on kasvanut viimeisimpinä vuosina huomattavasti. Erityisesti maissin viljelystä ovat kiinnostuneet nautatilat, joilla maissirehu käytetäänkin usein rehuseoksessa yhtenä energiaa tuovana komponenttina. Oikea-aikaisesti korjatun maissirehun energia-arvo on korkea ja tämän vuoksi sadonkorjuun ajoittamisella on suuri vaikutus rehun laatuun. Tutkimuksen tavoitteena oli selvittää, miten sadonkorjuu tulisi ajoittaa, jotta maissirehu olisi parhaimmillaan paitsi sadon määrän kannalta myös laadullisesti. Tutkimus toteutettiin kenttäkokeena Helsingin yliopiston Viikin opetus- ja tutkimustilalla kasvukaudella 2017. Ensimmäinen sadonkorjuu pyrittiin ajoittamaan siten, että kuiva-ainepitoisuus olisi noin 20% ja sitä seuraavat kolme korjuukertaa aina noin 14 vuorokautta edellisistä sadonkorjuista. Korjuukerrat olivat 120, 134, 156 ja 176 vuorokautta kylvöstä. Sadonkorjuun yhteydessä korjattu tuoremassa punnittiin, tuore- ja kuiva-ainesatojen laskemista varten. Lisäksi yhden metrin pituudelta kerättiin kasvit, joiden lukumäärä laskettiin sekä määritettiin yksittäisen kasvin kokonaismassa ja pituus. Lisäksi tähkien määrä laskettiin ja niiden massa punnittiin. Tähkien ominaisuuksien avulla määritettiin tähkien kehitysvaihe. Korjuuajankohta ei vaikuttanut maissin tuore- ja kuiva-ainesadon määrään. Sen sijaan laatuominaisuuksista primaariseen kuiva-ainepitoisuuteen ja tärkkelyksen pitoisuuteen korjuuajankohta vaikutti. Muihin sadon laatuominaisuuksiin korjuuajankohta ei vaikuttanut. Tärkein havainto tutkimuksessa oli, että sadonkorjuu ajoitetaan tähkien R3 kehitysvaiheen jälkeen. Rehun laadun kannalta on kuitenkin parempi, jos korjuu tehdään vielä myöhemmissä tähkän kehitysvaiheissa, sillä sato on laadultaan parhaimmillaan vasta R5 vaiheessa. Tähkien R3 kehitysvaiheen jälkeen laatuominaisuudet, kuten primaarinen kuiva-aine-, tärkkelys- sekä NDF:n pitoisuudet nousivat tähkien edelleen kehittyessä. Vastaavasti sadon sulavuus, sokerin– ja raakavalkuaisen pitoisuus laskivat korjuun ajoittuessa myöhempään ajankohtaan kasvukaudella. Optimaalisimmaksi sadonkorjuun ajankohdaksi näiden tulosten perusteella voi suositella tähkien R5 -kehitysvaihetta, sillä tällöin rehun laatu on parhaimmillaan.

Fertilizing of the fields with selenium has been an effective way to add organic selenium to the human and animal nutrition. Traditionally the additional selenium has been inorganic sodium selenite but nowadays there is also additional organic selenium available. This master theses has purpose to find out how additional amino acids and selenium from different sources effects to weight gain an feed efficiency of broilers as well as absorption of selenium to broilers breast muscle. The hypothesis was that diets with organic selenium decrease intake of the feed and improve feed efficiency and also increase selenium level in the breast mus-cle. Additionally restricting the level of additional amino acids would impair more absorption of the organic selenium that inorganic selenium. To this research two experiments were conducted. The first experiment was held between November 2nd and November 14th in 2012 and the second experiment was held between February 2nd and March 22nd in 2013. The first experiment was completely randomized feeding comparison of two different groups and the second experiment was completely randomized growth experiment of four different groups. In the first experiment there was compared the effects of two different source and level of selenium and in the second experiment there was added also two different level of additional amino acids. The first experiment lasted 42 days and the second experiment lasted 40 days. In the first experiment there was 240 and in the second 320 newly hatched Ross 508 roosters. The nestlings were divided in the first experiment to 24 group hatches of 10 birds and in the second experiment to 16 group hatches of twenty birds. In both experiments the feed intake was measured per hatch and the weight of the birds was measured individually at age of 0, 7, 20 and 33 but in calculations there was used weight average of the hatch. The organic selenium has no effect to weight gain, muscle gain, feed efficiency ratio nor the total weight of the broilers compared to inorganic selenium. Restricting the amount of the amino acids did impair the daily gain and feed efficiency ratio. There was not observed interaction of amino acids and organic selenium. Source of the selenium has no effect to selenium absorption but restricting amount of amino acids did impair the absorption. Larger selenium dosage increased the amount of selenium in the breast muscle.

Variation of the protein and amino acid content of barley, wheat and oats were studied. Diets based on grain samples of different protein content were optimized for pigs and poultry.The study went on to optimize diets for pigs and poultry with grains of different protein contents. The amino acid and raw protein analysis was undertaken on 38 grain samples. Correlations were calculated between different variables in grain samples and linear regression analysis was conducted between the protein and amino acid composition. The best estimate for amino acid concentrations of cereals was the protein content. The relative content of amino acids decreases as protein content increases and especially so in barley and wheat. Most reliable regression equations between amino acid and protein content were made for barley and wheat samples. For oat reliable regression equations could not be made. Oats also differed by other features from barley and wheat as it correlated with different variables compared to barley and wheat. Amount of needed protein concentrate levels decreased when barley and wheat protein and amino acid contents were considered in optimization. Protein concentrate levels did not decrease when used oat sample with highest protein content.

Every company receives customer complaints and negative customer feedback. With functional customer complaint management and service recovery processes, it is possible to restore customers’ satisfaction and loyalty towards the company, enhance the self-efficacy of the staff and improve service processes of the company. Objective of this study was to find out, how recovery process is recognized, how it is utilized, and which are the main needs of development. In this study, current customer complaint process is examined through service recovery theory highlighting the role of process recovery and employee recovery. The effect of current customer complaint process on customer experience is also discussed. The research material of this study was collected in summer 2020 by questionnaire. Questionnaire was sent by e-mail to personnel who handle customer complaints in their tasks. The questionnaire was sent to 323 person and 85 approved responses were received. The response rate was 26 %. Research method in this thesis is quantitative analysis. Based on the results, the customer complaint process could be utilized further. Better distribution of responsibility, recognizing the importance of customer complaint and service blueprints will improve the quality of the customer complaint process. Furthermore, customer complaint process should be more straightforward and continuous training for personnel should be added. Employees have high motivation to restore customer satisfaction and secure good customer experience. Further study is needed to clarify the customers’ view of customer experience of customer complaint process.

The end point chopping temperature influences different properties of the sausage batter and consequently the properties of the final product. If the end point chopping temperature of the sausage batter is either too high or too low the properties of the final product, especially texture, colour, sensory properties, and water-holding capacity (in this context cooking loss) will be affected. However, in the industrial scale, the end point chopping temperatures are hard to alter due to the continuous nature of the processes. The aim of the thesis was to study could marked differences be found from sausage batches that had been chopped to opposite extreme end point chopping temperatures that had been reported by the sausage factory staff. The study was carried out by using following three different meat choppers: standard bowl chopper, two different continuous choppers. Two separate, identically composed preblended meat masses were prepared in such way that their initial temperatures were approximately 0 and 10 °C. The preblended mass with lower initial temperature was made from non-frozen and frozen thawed meat assortments (50 % and 50 %), whereas the other mass was produced from non-frozen meat only. In turn, the chosen values for end point chopping temperatures were 13 and 23 °C. Texture properties, colour and cooking loss were determined from the cooked sausages and the differences were compared statistically.