Quality characteristics of edible linseed oil

In this review the quality properties of linseed oil for food uses are discussed as well as factors affecting this quality. Linseed oil has a favourable fatty acid composition with a high linolenic acid content. Linseed oil contains nearly 60% á-linolenic acid, compared with 25% for plant oils generally. The content of linolenic acid and omega-3 fatty acids is reported to be high in linseed grown in northern latitudes. The composition of fatty acids, especially unsaturated fatty acids, reported in different studies varies considerably for linseed oil. This variation depends mainly on differences in the examined varieties and industrial processing treatments. The fatty acid composition leads also to some problems, rancidity probably being the most challenging. Some information has been published concerning oxidation and taste, whereas only a few studies have focused on colour or microbiological quality. Rancidity negatively affects the taste and odour of the oil. There are available a few studies on effects of storage on composition of linseed oil. In general, storage and heat promote auto-oxidation of fats, as well as decrease the amounts of tocopherols and vitamin E in linseed oil. Several methods are available to promote the quality of the oil, including agronomic methods and methods of breeding as well as chemical, biotechnological and microbiological methods. Time of harvesting and weather conditions affect the quality and yield of the oil

Pellavan ja kuituhampun mikrobiologinen laatu kasviraaka-aineesta lämmöneristeeksi

Flax and hemp have traditionally been used mainly for textiles, but recently interest has also been focused on non-textile applications. Microbial quality throughout the whole processing chain of bast fibres has not previously been studied. This study concentrates on the microbial quality and possible microbial risks in the production chain of hemp and flax fibres and fibrous thermal insulations. In order to be able to utilize hemp and flax fibres, the bast fibres must be separated from the rest of the plant. Non-cellulosic components can be removed with various pretreatment processes, which are associated with a certain risk of microbial contamination. In this study enzymatic retting and steam explosion (STEX) were examined as pretreatment processes. On the basis of the results obtained in this study, the microbial contents on stalks of both plants studied increased at the end of the growing season and during the winter. However, by processing and mechanical separation it is possible to produce fibres containing less moulds and bacteria than the whole stem. Enzymatic treatment encouraged the growth of moulds in fibres. Steam explosion reduced the amount of moulds in fibres. Dry thermal treatment used in this study did not markedly reduce the amount of microbes. In this project an emission measurement chamber was developed which was suitable for measurements of emissions from both mat type and loose fill type insulations, and capable of interdisciplinary sampling. In this study, the highest amounts of fungal emissions were in the range of 10^3 10^5 cfu/m^3 from the flax and hemp insulations at 90% RH of air. The fungal emissions from stone wool, glass wool and recycled paper insulations were below 10^2 cfu/m^3 even at 90% RH. Equally low values were obtained from bast fibrous materials in lower humidities (at 30% and 80% RH of air). After drying of moulded insulations at 30% RH, the amounts of emitted moulds were in all cases higher compared to the emissions at 90% RH before drying. The most common fungi in bast fibres were Penicillium and Rhizopus. The widest variety of different fungi was in the untreated hemp and linseed fibres and in the commercial loose-fill flax insulation. Penicillium, Rhizopus and Paecilomyces were the most tolerant to steam explosion. According to the literature, the most common fungi in building materials and indoor air are Penicillium, Aspergillus and Cladosporium, which were all found in some of the bast fibre materials in this study. As organic materials, hemp and flax fibres contain high levels of nutrients for microbial growth. The amount of microbes can be controlled and somewhat decreased by the processing methods presented.Hamppua ja pellavaa on perinteisesti käytetty tekstiilien valmistukseen. Nykyään niinikuitukasvien käyttökohteet ovat laajentuneet, ja kuituja käytetään esimerkiksi komposiittien ja lämmöneristeiden valmistuksessa. Koko kasvikuitujen tuotantoketjun kattavaa mikrobiologisen laadun seurantaa ei ole aikaisemmin esitetty. Tässä tutkimuksessa selvitettiin hamppu- ja pellavakuitujen tuotantoprosessin mikrobiologista laatua sekä siihen liittyviä mahdollisia mikrobiologisia vaaroja. Jotta hamppu- ja pellavakuituja voidaan teollisesti hyödyntää, ne pitää ensin irrottaa korresta. Tämä on perinteisesti tehty erilaisilla liotusmenetelmillä, joihin usein liittyy mikrobiologisen kontaminoitumisen riski. Tässä tutkimuksessa selvitettiin entsyymiliotusta sekä höyryräjäytystä kuitujen irrotus- ja esikäsittelyinä. Tämän tutkimusten perusteella hamppu- ja pellavakorsien mikrobimäärä nousi kasvukauden loppua kohti sekä kevätkorjuumenetelmissä talven aikana. Kuitujakeessa mikrobipitoisuus kuitenkin oli pienempi kuin kokonaisessa korressa. Entsyymiliotus lisäsi kuitujen homepitoisuutta, eli sillä oli heikentävä vaikutus mikrobiologiseen laatuun. Höyryräjäytys alensi kuitujen homepitoisuutta, eli se saattaisi olla toimiva esikäsittely tilanteissa, joissa kuitujen mikrobipitoisuutta halutaan alentaa. Teollista kuumennuskäsittelyä simuloivalla kuivalla lämpökäsittelyllä ei ollut merkittävää vaikutusta kuitujen mikrobipitoisuuteen. Tutkimusprojektin aikana kehitettiin yhteistyönä emissiokammio, jolla pystytään tutkimaan sekä levymäisistä että puhallusvillatyyppisistä lämmöneristeistä ilmaan irtoavia fysikaalisia, kemiallisia ja mikrobiologisia emissioita. Kun ilmankosteus oli 30% tai 80%, kaikkien tutkittujen eristemateriaalien home-emissiot olivat suhteellisen alhaisia. Suurimmat home-emissiot irtosivat kammion ilmaan hamppu- ja pellavaeristeistä suhteellisen ilmankosteuden ollessa 90%. Lasi- ja kivivilla- sekä selluvillaeristeiden home-emissiot pysyivät alhaisella tasolla myös korkeammassa ilmankosteudessa. Kun homehtunut eristenäyte kuivattiin kammiossa, siitä ilmaan irtoavien home-emissioiden määrä kasvoi. Yleisimmät homesuvut kuitunäytteissä olivat Penicillium ja Rhizopus. Eniten eri homesukuja löydettiin käsittelemättömistä hamppu- ja pellavakuiduista sekä kaupallisesta puhalluspellavaeristeestä. Höyryräjäytyksen jälkeen kuiduissa oli merkittävästi vähemmän eri homesukuja kuin ennen käsittelyä. Orgaanisena materiaalina hamppu ja pellava sisältävät runsaasti ravinteita. Kuitujen käytön kannalta on hyödyksi, että tietyillä esikäsittelyillä voidaan vähentää kuitujen ja eristeiden mikrobimäärää

PTPRD and CNTNAP2 as markers of tumor aggressiveness in oligodendrogliomas

Oligodendrogliomas are typically associated with the most favorable prognosis among diffuse gliomas. However, many of the tumors progress, eventually leading to patient death. To characterize the changes associated with oligodendroglioma recurrence and progression, we analyzed two recurrent oligodendroglioma tumors upon diagnosis and after tumor relapse based on whole-genome and RNA sequencing. Relapsed tumors were diagnosed as glioblastomas with an oligodendroglioma component before the World Health Organization classification update in 2016. Both patients died within 12 months after relapse. One patient carried an inactivating POLE mutation leading to a clearly hypermutated progressed tumor. Strikingly, both relapsed tumors carried focal chromosomal rearrangements in PTPRD and CNTNAP2 genes with associated decreased gene expression. TP53 mutation was also detected in both patients after tumor relapse. In The Cancer Genome Atlas (TCGA) diffuse glioma cohort, PTPRD and CNTNAP2 expression decreased by tumor grade in oligodendrogliomas and PTPRD expression also in IDH-mutant astrocytomas. Low expression of the genes was associated with poor overall survival. Our analysis provides information about aggressive oligodendrogliomas with worse prognosis and suggests that PTPRD and CNTNAP2 expression could represent an informative marker for their stratification.publishedVersionPeer reviewe

Hygienic quality of stem fractions of mechanically processed fibre hemp and linseed

Niinikuitu on tärkein teknisiin sovelluksiin, kuten lämmöneristeisiin ja pakkausmateriaaleihin käytettävä niinikuitukasvien jae. Niinikuitukasvien jakeiden hygieeninen laatu on tärkeää lämmöneristeissä, jotka voivat vaikuttaa sisäilman laatuun. Pakkausmateriaalit voivat olla yhteydessä esim. ruokaan, mikä korostaa hygieenisen laadun merkitystä. Tutkimuksen tavoitteena oli kartoittaa syksyllä tai keväällä korjatun, mekaanisesti jakeistetun öljypellavan ja kuituhampun hygieenistä laatua, jota kuvattiin mikrobimäärän avulla. Lisäksi tutkittiin mikrobimäärien ja tuhkapitoisuuden mahdollista korrelaatiota. Tutkittavana oli kaksi kasvilajia, kuituhamppu ja öljypellava. Kasvit viljeltiin ja korjattiin Siuntiossa, Etelä- Suomessa vuosina 2002 2003. Korret korjattiin syksyllä ennen pakkasia, ensimmäisten pakkasten jälkeen tai keväällä, minkä jälkeen korret jakeistettiin mekaanisesti. Jakeiden kokonaismikrobimäärät selvitettiin Hygicult®- kastolevyillä. Jakeiden mikrobimäärät vaihtelivat 103 ja 109 välillä. Aikaisen pakkasen jälkeen tai keväällä korjatun kuituhampun niinikuitu sisälsi vähiten homeita, mutta talven ja kevään aikana bakteerien ja hiivojen määrä kasvoi. Mekaanisesti jakeistettu kuitu ja päistäre sisälsivät vähemmän mikrobeja kuin kokonainen korsi. Multakontaminaatiota pidetään yleisesti hygieniariskinä. Multakontaminaatio lisää korren tuhkapitoisuutta. Jakeiden tuhkapitoisuus vaihteli 1 ja 14 % välillä. Niinikuitujakeen tuhkapitoisuus oli alhaisempi kuin syksyllä korjatun korren tuhkapitoisuus. Korren ja päistäreen tuhkapitoisuus laski talven aikana 1,6 %, ja keväällä korjatusta korresta erotetun kuidun tuhkapitoisuus oli niitäkin alhaisempi (0,9 %). Mikrobi- ja tuhkapitoisuuksien välillä ei havaittu korrelaatiota.Bast fibre is the most important fraction of bast fibre plants for technical products, i.e. thermal insulations and packaging materials. The hygienic quality of the various fractions of bast fibre plants is of interest in thermal insulations, because it may affect the quality of indoor air. Packaging materials may be associated e.g. with foodstuffs, which highlights the importance of hygienic quality. The aim of this study was to screen the hygienic quality, determined as microbial content, of mechanically fractionated fibre hemp and linseed plants harvested in the autumn before frost, after early frost and in spring. In addition, the possible correlation between microbes and ash was investigated. Two plant species, fibre hemp and linseed were studied. The plants were cultivated in Siuntio in southern Finland during the years 2002 and 2003, harvested in autumn or in spring and mechanically fractionated. The microbial contents of the fractions were examined by measuring the total number of microbes using Hygicult® growing slides. The microbial content of fractions of fibre hemp and linseed varied between 103 and 109 cfu/gdw. The fibre of hemp harvested after early frost or in spring had the lowest amount of moulds, but during winter and spring the amounts of bacteria and yeasts increased in hemp. Mechanically separated fibre and shive contained less microbes than the stalk. Ash contents of all examined samples of stems and stem fractions varied between 1% and 14%. The fibre after fractionating had a lower ash content (2.3 3.3%) than that of stems (4.4 6.9%) harvested in the autumn. The ash content of stem and shive decreased to 1.6% during winter, the ash content of fibre being even somewhat lower (0.9%). No correlation was observed between the contents of microbes and ash.vokMekaanisesti jakeistetun kuituhampun ja öljypellavan korren hygieeninen laat

PTPRD and CNTNAP2 as markers of tumor aggressiveness in oligodendrogliomas.

Oligodendrogliomas are typically associated with the most favorable prognosis among diffuse gliomas. However, many of the tumors progress, eventually leading to patient death. To characterize the changes associated with oligodendroglioma recurrence and progression, we analyzed two recurrent oligodendroglioma tumors upon diagnosis and after tumor relapse based on whole-genome and RNA sequencing. Relapsed tumors were diagnosed as glioblastomas with an oligodendroglioma component before the World Health Organization classification update in 2016. Both patients died within 12 months after relapse. One patient carried an inactivating POLE mutation leading to a clearly hypermutated progressed tumor. Strikingly, both relapsed tumors carried focal chromosomal rearrangements in PTPRD and CNTNAP2 genes with associated decreased gene expression. TP53 mutation was also detected in both patients after tumor relapse. In The Cancer Genome Atlas (TCGA) diffuse glioma cohort, PTPRD and CNTNAP2 expression decreased by tumor grade in oligodendrogliomas and PTPRD expression also in IDH-mutant astrocytomas. Low expression of the genes was associated with poor overall survival. Our analysis provides information about aggressive oligodendrogliomas with worse prognosis and suggests that PTPRD and CNTNAP2 expression could represent an informative marker for their stratification