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Received: November 11th, 2021 ; Accepted: January 30th, 2022 ; Published: March 17th, 2022 ; Correspondence: linda.legzdina@arei.lv Lipids are a minor nutritional component of barley (Hordeum vulgare L.) grain and have not been as widely explored as the major components. The aim of this study was to investigate the effect of genotype and environment, including conventional farming system with three crop management regimes, differing in agrochemical input, and organic farming system, on oil content and fatty acid composition in grain of two covered and four hulless spring barley genotypes during two growing seasons. Genotype significantly affected oil content and it was on average 4.26% and ranged in individual barley samples from 2.87 to 5.53%. We found linoleic, oleic, palmitic, α-linolenic, stearic and capric fatty acids in average proportions of 55.6; 21.3; 18.6; 3.7; 0.6 and 0.4%, respectively. Higher average oil content and proportion of α-linolenic acid was found in covered barley. Crop management regime did not significantly affect oil content but had some effect on the proportion of linoleic, α-linolenic, oleic and stearic acid. Decrease of chemical inputs was in favour of oil content and proportion of α-linolenic, oleic and stearic acids but did not promote linoleic acid. Waxy hulless barley line with high oil content and a very high proportion of linoleic acid was identified.

Synthesis and properties of 2-arylmethyldimedones and 3-arylmethyl-4-hydroxy-quinolin-2(1H)-ones

Hempseed oil, as well as other oils containing polyunsaturated fatty acids, is subjected to oxidation processes caused by air, heat or light. Usually these processes are suppressed by addition of various synthetic phenol type antioxidants. The aim of current research was to increase oxidative stability of vegetable oils with natural antioxidants. Herein, we demonstrate that the oxidative stability can be increased with natural antioxidants present in oat hulls and sea buckthorn pomace – by-products of food processing. Extracts from pomace and hulls were prepared by maceration of ground plant material in the hempseed oil. The extraction was accelerated by ultrasound. It was established that the highest amount of polyphenols in extracts of both plant materials can be achieved within 30 min; further increase of extraction time sometimes even reduced the total amount of polyphenols. The highest amount of polyphenols in sea buckthorn extracts was 7.73±0.29 mg GAE 100 g-1, but in oat hull extracts – 4.63±0.21 mg GAE 100 g-1, when extracts were prepared by ultrasonification of hempseed oil containing 5% wt of plant material. Various amounts of plant material additives were used for extraction under optimized conditions. The highest antioxidant activity (expressed as ratio of time when peroxide value of sample and blank reaches 48 meq O2 kg-1) – 1.51±0.05 and 1.40±0.06 to 1.44±0.02, respectively – had extracts obtained from 1% wt additive of sea buckthorn pomace or 2.5-5% wt additive of oat hulls. The prepared hempseed oil extracts demonstrated higher oxidative stability than hempseed oil containing 0.02% additive of synthetic antioxidant BHT.

the oxidative stability of the oat oil extracts was studied

Tēzēs aprakstīta avenantramīdu ieguve kondensējot aromātiskos aldehīdus ar amīdiem vai2-metilbenzo[d][1,3]oksazīn-4-onu.

FAME extracts of black currant have been investigated

Biobased additives for chain saw lubricants

aprakstītas krūmcidoniju sēklu attīrīšanas iespējas no cianogēnajām vielām

Krūmcidoniju sēklas - potenciāls antioksidantu avots polinepiesātināto augu eļļas oksidatīvās stabilitātes uzlabošanai.

Pēdējos gados arvien lielāku nozīmi tautsaimniecībā iegūst no atjaunojamiem dabas resursiem iegūstamās alternatīvās degvielas, tai skaitā arī biodīzelis. Tomēr tā veiksmīgu izmantošanu ierobežo taukskābju monoalkilesteru nepietiekamā oksidatīvā stabilitāte, kā arī neapmierinošās zemo temperatūru īpašības. Tā kā abi šie faktori lielā mērā ir saistīti tieši ar taukskābju piesātinātības pakāpi, tad pētījumiem izmantoti biodīzeļi, kas sintezēti no ļoti atšķirīgām taukvielām – stipri nepiesātinātās linu eļļas, dzīvnieku taukiem, kas pamatā veidoti no piesātinātām taukskābēm, kā arī rapšu eļļas. Biodīzeļu oksidatīvās stabilitātes izmaiņas BHA un BHT klātbūtnē tika vērtētas izmantojot Rancimāta indukcijas periodu. Pētīta dažādu komerciāli pieejamo temperatūras depresantu un no biodīzeļa ražošanas blakusprodukta – jēlglicerīna – sintezētu acetālu un ketālu ietekme uz taukskābju metilesteru auksta filtra nosprostošanās punktu, sastingšanas un saduļķošanās punktiem.

As a result of the wide availability of social media, cheap flights and free intra-EU movement it has become considerably easier to maintain links with the country of origin than it was only a generation ago. Therefore, the language and identity formation among children of recent migrants might be significantly different from the experiences of children of the previous generations. The aim of this paper is to examine the perceptions of parents on the formation of national and transnational identity among the ‘1.5 generation migrant children’ – the children born in Latvia but growing up in England and the factors affecting them. In particular, this article seeks to understand whether 1.5 generation migrant children from Latvia construct strong transnational identities by maintaining equally strong ties with their country of origin and mother tongue and, at the same time, intensively creating networks, learning and using the language of the new home country. The results of 16 semi-structured in-depth interviews with the parents of these children reveal that the 1.5 generation Latvian migrants are on a path of becoming English-dominant bilinguals. So far there is little evidence of the development of a strong transnational identity among 1.5 generation migrant children from Latvia. Instead, this study observed a tendency towards an active integration and assimilation into the new host country facilitated by their parents or occurring despite their parents’ efforts to maintain ties with Latvia. These findings suggest that rather than the national identity of the country of origin being supplemented with a new additional national identity – that of the country of settlement – the identity of the country of origin becomes dominated by it instead.