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Havre har de senaste åren uppmärksammats för sina många positiva hälsoeffekter och Lantmännen har därför tagit fram en ny havresort med högre halt β-glukaner och protein än vanlig svensk havre. Havreprotein kan extraheras med en alkalisk metod genom att proteinerna görs lösliga vid pH 9 och sedan fälls ut vid pH 5. Syftet med detta arbete var att undersöka om det är möjligt att avfetta havreproteinisolat med hjälp av ultraljud samt undersöka hur lipasaktiviteten påverkas. En ultraljudsprob (diameter 1,4 cm, amplitud 99 µm, frekvens 24 kHz) behandlade prover antingen vid pH 9 eller pH 5 i extraktionen med antingen 80 J/g havre eller 800 J/g havre. Resultatet visar att fetthalten i proteinisolatet och andelen fett som extraheras från havremjölet inte påverkas av ultraljudsbehandlingen. Fetthalten var 11-17 % av TS i proteinisolatet och utbytet av fett 32-44 %. Proteinhalten i isolatet påverkades ej men proteinutbytet minskade lite vid ultraljudsbehandling behandling vid pH 5, från 65-80 % till 50‑60 %. Lipaser inaktiveras av proteinextraktionen och kunde inte detekteras i proteinisolatet. Tidigare studier har visat att ultraljud kan förkorta extraktionstiden i en fettextraktion, men inte ersätta lösningsmedel. Vidare studier skulle kunna undersöka om etanolextraktion av fettet i havre kan effektiviseras av ultraljudsbehandling. / In recent years, oats have received attention for their many positive health benefits, and therefor Lantmännen has developed a new oat variety with higher content of β-glucans and protein than ordinary Swedish oats. Oat protein can be extracted by an alkaline method, first solubilized at pH 9 and then precipitated at pH 5. The aim of this work was to investigate whether it is possible to defat oat protein isolates using ultrasound and to investigate how lipase activity is affected. With an ultrasound probe (diameter 1.4 cm, amplitude 99 µm, frequency 24 kHz) samples were treated at either pH 9 or pH 5 in the extraction with either 80 J/g oats or 800 J/g oats. The results show that the fat content in the protein isolate and the fraction of fat that is extracted from the oat meal is not affected by the ultrasound treatment. The fat content was 11-17% of dry matter in the protein isolate and the yield of fat 32-44%. The protein concentration in the protein isolate was not affected, but the protein yield decreased slightly by ultrasonic treatment at pH 5, from 65-80% to 50-60%. Lipases were found to be inactivated by protein extraction and could not be detected in the protein isolate. Previous studies have shown that ultrasound can shorten the extraction time in a fat extraction, while not replace solvents. Further studies could investigate whether ethanol extraction of oats can be made more efficient by ultrasound treatment.

Syftet med studien var att etablera Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry(MALDI-TOF MS) och onlinedatabasen Mass Spectrometry identification platform(MSI) som metod för identifiering av dermatofyter och mögelsvamp. Svamparna inkuberades 3 eller 6 dagar aerobt i 30°C på Sabouraud dextros agar. Två olika extraktionsmetoder användes innan analys med MALDI-TOF MS. Spektra analyserades med Flexcontrol version 3.4 och resulterade i scorevärde. De spektra som framkom skickades även till MSI för ytterligare analys där resultat erhölls som sannolikhet i procent. Av de ursprungliga 23 st prov identifierades totalt 22st(95,6%) efter 3 eller 6 dagars inkubation och med extraktionsmetod 1 eller 2. MSI databasen var mer omfattande än den interna databasen, men använde sig inte av de aktuella namnen. Behovet av artidentifiering kan ifrågasättas, då många dermatofyter och mögel inom samma släkte behandlas på samma sätt. Artbestämning för immunsupprimerade patienter kan däremot vara viktigt. Studien var lyckad och metoderna kommer tillämpas inom en snar framtid på Klinisk Mikrobiologi i Halmstad. / The purpose of this study was to establish Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry(MALDI-TOF MS) and the online database Mass Spectrometry identification platform(MSI) as a method for identification of dermatophytes and molds. The fungi were incubated 3 or 6 days aerobic in 30°C on Sabouraud dextrose agar. Two different extraction methods were used before analysis with MALDI-TOF MS. Spectra analyzed with Flexcontrol version 3.4 resulted in score values. The same spectra was later sent for analysis with MSI and the result obtained was seen as probability in percent. Of the original 23 samples a total of 22(95,6%) samples were identified after 3 or 6 days of incubation and by extraction method 1 or 2.  The MSI database was more comprehensive than the internal database, but did not use the current fungi names. The necessity of species identification can be questioned, since dermatophytes and molds within the same genera is treated the same way. Species identification for immunosuppressed patients could however be significant. The study was successful and the methods will be applied within a near future in the Clinical Microbiology laboratory in Halmstad.

Oat products have become more and more popular in today´s society, as oats have healthy properties and can be classified as gluten-free. Oats also contain good fiber in the form of beta-glucans which are a soluble type of fiber that can lower cholesterol levels in the blood. It has also become more popular to use oats in various products as an ingredient and in these cases purified oat protein may be an option. Oat protein extract can be obtained by alkaline extraction at pH 9 and precipitation of the proteins at pH 5. This protein extract then needs to de defatted to obtain a pure protein extrakt. One problem with oat protein is that the solubility is generally low, which makes it difficult to use the protein extract as an ingredient in food.  This report examined how the water holding capacity and the solubility of oat protein were affected by defatting by ethanol. The defatting was performed either on the oatmeal before the protein extraction or on the protein extract after the extraction. These two methods are called fat+alki and alki+fat respectively. After the defatting there was no fat left in the protein extracts and the protein content was about 90 %. The water holding capacity of defatted protein extract treated with the fat+alki method was 1,98 g/g and for alki+fat the value was 1,74 g/g, these values can be compared with the water holding capacity of the protein extract which was 0,88 g/g. Experiments done on the solubility of defatted protein extract confirmed that the solubility at pH 5 was lower than at pH 7,25 for the defatted protein, but no clear difference could be seen between the two different methods of defatting.  The conclusion that can be drawn from this study is that ethanol can be used to defat oat protein and that there will be no major difference in results for the fat content or protein content if the defatting is performed before or after the protein extraction. However, several of the experiments in the study need to be repeated to obtain more reliable results. There is also a need for more studies looking at alternative ways, which preferably do not use solvents, as solvents can pose a danger to the consumer.

The plastid is an important organelle that allows eukaryotes to photosynthesize. The endosymbiotic event that led to the development of a primary plastid occurred more than one billion years ago. Since then the organelle has undergone a significant genome reduction, losing a large portion of non-essential genes whose function is covered by the eukaryotic host. The majority of the proteins needed for essential plastid function are transcribed in the nucleus and translated in the cytosol. These proteins are then translocated across the inner and outer plastid membranes. The difference in where proteins are translated and transported can be used to study plastid evolution, this can be done by examining what proteins are present in the red algae plastid and comparing it to proteins found in other algae groups. In this project, the exact placement of the proteins, mainly plastid proteins is of interest. In order to localize and identify proteins in the algal cell, an efficient method of cell lysis, both total and incomplete, where the preservation of organelles is essential needs to be developed. This thesis examines a set of different methods of cell lysis, both complete and incomplete, coupled with organelle fractionation, to achieve the isolation of proteins belonging to the different cellular compartments. I show that complete cell lysis with bead milling using 0.1-0.5 mm silica beads is more efficient than a method using a Dounce homogenizer. For incomplete lysis, I show that nitrogen cavitation at 750 psi for 15 min and 1,000 psi for 30 min provides the same level of cellular lysis, indicating that the nitrogen gas equilibrates within 15 minutes. Organelle fractionation with OptiprepTM gradient showed that the majority of the sample did not travel through the gradient, staying in the first layer, which also prevented revelation of the protein pattern on an SDS-PAGE gel, indicating insufficient centrifugation. A great deal of optimization is still required to make these methods as efficient as possible. The step that requires the most optimization is sample preparation for nitrogen cavitation and the use of an ultracentrifuge.

Som följd av dagens ökning i global befolkning och köttproduktion är alternativa hållbara köttsubstitut mycket eftertraktat. Som basal råvara kan växter eller mikrobiella produkter utnyttjas för proteinrika hållbara livsmedelsprodukter. Detta arbete syftar till att undersöka olika proteinextraktionsmetoder som i nuläget används för att erhålla ett proteinisolat som kan ha användning i livsmedelsindustrin. Utvalda råvaror som kommer studeras och diskuteras är ärta, quinoa, mjölmask och filamentösa svampar. Allmän information för varje råvara diskuteras men fokus har lagts på att studera processer för att extrahera proteiner till ett isolat från råvarorna. Arbetet inkluderar generella tillvägagångssätt vad gäller proteinextraktion likväl som mer specifika metoder från enskilda försök att extrahera ett visst protein. Slutligen jämförs val av extraktionsmetoder och vilka råvaror som idag är i kommersiellt bruk och reflekterande tankar om varför inte vissa råvaror hunnit lika långt i utvecklingen i proteinextraktion som andra. / As a result of today's increase in global population and meat production, alternative and more sustainable meat substitutes are highly sought after. As a basic raw material, plants or microbial products can be utilized for protein-rich sustainable food products. This work aims to investigate various protein extraction methods currently used to obtain a protein isolate that can be of use in the food industry. Selected raw materials studied and discussed are pea, quinoa, flour worm and filamentous fungus. General information for each raw material is discussed, however focus has been on studying processes for extracting proteins into an isolate from the raw materials. The work includes general methods to protein extraction as well as more specific methods from individual attempts to extract a specific protein. Finally, the extraction methods are compared, the raw materials that are currently in commercial use are discussed as well as thoughts why some raw materials have not progressed as far in protein extraction as others are compared.