Evaluation of Fatty Acid Compositions of Some Important Wild and Domestic Turkish Mustard Genotypes ( Brassica spp . )

The seed oil samples of 57 mustard genotypes belonging to six species of mustard (Brassica spp.) Brassica juncea (31 genotypes), B. rapa (6 genotypes), B. napus (2 genotypes), B. nigra (6 genotypes), B. arvensis (10 genotypes) and B. alba (2 genotypes) collected from USA gene bank and diverse ecologies of Turkey were used as research material and evaluated for their fatty acid composition by gas-liquid chromatography (GLC). The aim of this study was to evaluation of fatty acid compositions of some important wild and domestic Turkish mustard genotypes (Brassica spp.). The results showed significant variability among all genotypes for fatty acid composition. Erusic acid (C22:1; 20.63-47.87%), oleic acid (C18:1; 7.4224.54%) and linoleic acid (C18:2; 9.61-25.11%) were determined to be the dominant fatty acids among all genotypes. It has been observed that the results in wild mustards have too many resemblances with the composition of fatty acid of mustard which is used by people in alternative medical science, paint, food industry and biodisel production. The great variability in seed oil contents in Brassica genotypes showed their potential for use in future breeding programs. ARTICLE HISTORY Received: 29 May 2018 Revised: 01 August 2018 Accepted: 09 September 2018


INTRODUCTION
Brassicas are members of the Brassicaceae (Cruciferae) family.Brassicaeae comprise a diverse family of plants and provide one of the most extensive and varied range of end products used by man from a single plant genus [1].Brassica rapa (rapeseed or rape mustard), B. juncea (Asian mustard or brown mustard), B. arvensis (charlock), B. nigra (black mustard) and B. alba (white or yellow mustard) are some of the important species of Brassicaceae family.Turkey has a rich flora; more than 9000 flowering plant species.The family Brassicaceae contains 84 genera with 441 species [2].Brassica alba L., B. arvensis L., B. nigra L. and B. juncea L. family Cruciferae, grow in Turkey under natural conditions as weed (3,4).
Brassica species are cultivated extensively to produce edible and industrial oils throughout the world.They occupy a unique position in world agriculture as a source of vegetables, oilseed, forage and fodder, green manure and condiments [5][6][7].Brassica seed oil is used for the edible purpose, as industrial lubricants and as a base for polymer synthesis.Oilseed brassica cake is used as a source of protein in animal feeds [8,9].The oil is commonly used for cooking and to add a hot and spicy flavor to food [10].As a crop, they are also one of the maximum oil yielding and high protein containing oilseed species [1,11].
Mustard oil contains the major saturated fatty acids like palmitic and stearic acids along with mono and polyunsaturated fatty acids like oleic, eicosenoic, erucic, linoleic and linolenic acids.The fatty acid composition of the seed oil depends on the genetic, ecological, morphological, physiological and cultural factors.There may be big or small differences among Brassica species in terms of fatty acid composition and it may be changeable to a small and large scale depending on this factors [12,13,14,15].To know the fatty acid composition of Brassica species oil makes oil production possible for special using purposes.Thus, it would be possible to produce suitable oils by cultivating the desired genotypes.
The purpose of the study was to evaluate seed fatty compositions of 57 mustard genotypes Brassica belong to six species which selected from different mustard genotypes as a potential material for starting mustard breeding programs in Turkey.

RESULTS AND DISCUSSION
The results indicated that the major saturated fatty acids like palmitic and stearic acids along with mono and polyunsaturated fatty acids like oleic, eicosenoic, erucic, linoleic and linolenic acids were found in the oil.Number of genotypes of mustard were taken for fatty acid analysis.The fatty acid composition was variable among 57 different genotypes.Overall a total of 15 fatty acid components were detected (Table 3).The saturated fatty acids mainly include palmitic acid (C16:0; 2.11% in BNa-14-Turkey, Tekirdağ of B. napus-4.38 % in BA2-Turkey, Tokat of B. arvensis); stearic acid (C18:0; 1.17   3).Erusic acid (C22:1), oleic acid (C18:1) and linoleic acid (C18:2) were determined to be dominant fatty acids among all genotypes.The maximum total saturated fatty acids percent was observed in BA7-Turkey, Şereflikoçhisar of B. arvensis (10.18%) while the minimum oil percent was noted in BR-A48-Turkey, Tekirdağ of B. rapa genotype (5.25%).The maximum total monounsaturated fatty acid percent was obtained in BA7-Turkey, Şereflikoçhisar of B. arvensis (75.23%) while the minimum fatty oil percent was noted in BJ-A20-India of B. juncea (50.90%).The maximum total polyunsaturated fatty acid percent was obtained in BJ-A20-India of B.juncea (41.56%) while the minimum in BA7-Turkey, Şereflikoçhisar of B. arvensis (15.27%).Seed oil quality and utility largely depend on fatty acid composition.Fatty acids exhibit rich variety, exhibiting variable fatty acid composition and content across species (and even across varieties).Therefore, fatty acid composition and content profiles can be used as fingerprints to identify useful biological resources, in addition to their current use for oil authentication [16,17].The differences between fatty acids among genotypes were very obvious.Especially oleic acid (7.42 to 24.54%), linoleic acid (5.81 to 23.97%) and erusic acid (20.87 to 50.25%) were the most prominent.These differences in the fatty acid profile may be due to the variations in phenotypic or environmental conditions as well as the genetic background of the experimental material [18].Both genotypic and phenotypic conditions (environmental parameters) determine the amount and quality of fatty acids in plant [15].Maturation and harvest time of plants drought ere found to have significant effects on the fatty acid composition of the seeds [19][20][21][22][23].It is effective to choose the accessions with high monounsaturated fatty acid (MUFA) content as optimal germplasm resources for biodiesel production [17,24].The significant variability in seed oil contents among Brassica genotypes showed their potential for use in future breeding programs and supported the findings of [25][26][27] who also recorded great variations in seed oil contents among different Brassica species [28].

CONCLUSION
To know the fatty acid composition of Brassica species oil makes oil production possible for special using purposes.Genotypes belonging to six species of mustard evaluated in our study exhibited an important level of diversity for fatty acid compositions.Oleic acid (7.42 to 24.54%), linoleic acid (5.81 to 23.97%) and erusic acid (20.87 to 50.25%) were the most prominent.The result of our study showed that Brassica genotypes have significant potential for use in future breeding programs due to their significantly differed fatty acid compositions.While BJ-A20-India of Brassica juncea has maximum percent of total polyunsaturated fatty acid; BA7-Turkey, Şereflikoçhisar of Brassica arvensis was selected as promising genotype in terms of saturated and monounsaturated fatty acid contents.Especially the high erucic acid genotypes can be used for industrial applications.Furthermore these species are crossed to cultivated species for special using purposes and can be used as a new source.Therefore, an extensive work on these genotypes could suggest them in future breeding programs under Turkish conditions.

Table 1 .
Growing season and long term monthly meteorological data of the experimental area, where the Brassica genotypes were sown for experimantal purposes

Table 2 .
Soil samples features belonging to the experimental areaData were ontained from the Soil Fertilizer and Water Resources Institute

Table 3 .
Fatty acid composition of mustard genotypes belong to Brassica species