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Hosakatte Niranjana Murthy - One of the best experts on this subject based on the ideXlab platform.
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The effects of gamma and ethylmethanesulphonate treatments on agronomical traits of Niger (Guizotia Abyssinica Cass.).
African Journal of Biotechnology, 2009Co-Authors: Poornananda Madhava Naik, Hosakatte Niranjana MurthyAbstract:Seeds of niger (Guizotia Abyssinica Cass.) cultivar N-71 were exposed to different doses of gamma rays ranging from 0 -152 Gy and varying concentration of ethyl methanesulphonate ranging from 0 - 104 mM. Variations in the percentage of germination and survival, plant height, number of leaves/plant, leaf length, leaf width, number of primary branches, capitulum size, head size, number of ray florets/capitulum, number of disc florets/capitulum, number of capitula/plant, number of seeds/capitulum, seed yield/plant, 1000 seed weight were recorded in the M1 and M2 generations. Plants showed decreased growth with increased dose and concentration of the mutagens. There were dose and concentration related effects of the mutagenic treatments on quantitative traits resulting in reduction in traits such as germination and survival percentages, plant height, leaf length and width, number of primary branches and 1000 seeds weight, but increases in number of capitula/plant, number of seeds/capitulum and seed yield/plant was observed in 52 and 78 mM treated M2 generated plants. Improved oil content was found in gamma ray treated (38, 114, and 152 Gy) M2 plants and also in 78 mM EMS treated M2 plants. Early flowering was found in gamma (76 Gy) treated M2plants. Key words: Gamma ray, ethyl methanesulphonate, niger, agronomical trait, M1generation, M2 generation.
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Somatic embryogenesis and plant regeneration from cell suspension culture of niger ( Guizotia Abyssinica Cass.)
Acta Physiologiae Plantarum, 2009Co-Authors: Poornananda Madhava Naik, Hosakatte Niranjana MurthyAbstract:Somatic embryogenesis was achieved from cell suspension cultures of niger (Guizotia Abyssinica Cass.). Initially, friable embryogenic calluses were induced from cotyledonary leaves of niger on Murashige and Skoog (MS) agar medium containing 5 μM 2,4-Dichlorophenoxyacetic acid (2,4-D) and 0.5 μM kinetin (KIN). Cell suspension cultures were established by using embryogenic calluses in MS liquid medium containing 5 μM 2,4-D and 0.5 μM KIN. Initiation of somatic embryogenesis and development up to globular stage from embryogenic cell clumps occurred in the liquid medium itself. Thereafter embryogenic cell aggregates were transferred to MS agar medium supplemented with 3 μM KIN for embryo differentiation, whereas maturation of somatic embryos occurred in MS agar medium containing 10 μM abscisic acid.
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Factors affecting in-vitro gynogenic haploid production in niger (Guizotia Abyssinica (L. f.) Cass.)
Plant Growth Regulation, 2007Co-Authors: J. G. Bhat, Hosakatte Niranjana MurthyAbstract:The effects of growth regulators, cold-pretreatment of flower buds, ovule (embryo sac) developmental stage and genotype on induction of gynogenesis in unpollinated ovule cultures were assessed in niger (Guizotia Abyssinica (L. f.) Cass.). Indirect callus-mediated gynogenesis occurred in cvs JNC-6 and Ootacamund when the ovules were cultured on MS medium supplemented with 30 g l−1 sucrose and 2,4-D either alone (0.5–2.0 μM) or in combination (2.0 μM) with different cytokinins, such as adenine, BA, 2iP and kinetin (0.5–2.0 μM). An optimum induction of gynogenesis was fostered on medium supplemented with 2.0 μM 2,4-D and 1.0 μM kinetin. Cold-pretreatment of flower buds had no stimulatory effect, but ovules collected one day before anthesis were most responsive to gynogenesis. The results showed significant variations in genotypic competence for gynogenesis with cv. Ootacamund being the most responsive (12.5%) and cv. IGP-76 the least (2.5%). Gynogenic embryos differentiated and matured on media (30 g l−1 sucrose) supplemented with 0.5 μM NAA plus 1.0 μM kinetin, and 0.5 μM ABA, respectively. The haploidy (2n = 1x = 15) of gynogenic plants was confirmed by cytological analysis.
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Agrobacterium -mediated transformation of niger [ Guizotia Abyssinica (L. f.) Cass.] using seedling explants
Plant cell reports, 2003Co-Authors: Hosakatte Niranjana Murthy, J. H. Jeong, Yong-eui Choi, Kee-yoeup PaekAbstract:A protocol was developed for Agrobacterium-mediated genetic transformation of niger [Guizotia Abyssinica (L.f.) Cass.] using hypocotyl and cotyledon explants. Hypocotyls and cotyledons obtained from 7-day-old seedlings were co-cultivated with Agrobacterium tumefaciens strain EHA101/pIG121Hm that harbored genes for β-glucuronidase (GUS), kanamycin, and hygromycin resistance. Following co-cultivation, the hypocotyl and cotyledon explants were cultivated on MS medium containing 1 mg/l 6-benzylaminopurine (BA) for 3 days in darkness. Subsequently, hypocotyl and cotyledon explants were transferred to selective MS medium containing 1 mg/l BA, 10 mg/l hygromycin, 10 mg/l kanamycin, and 500 mg/l cefotaxime. After 6 weeks, hypocotyls and cotyledons produced multiple adventitious shoot buds, and these explants were subcultured to MS medium containing 1 mg/l BA, 30 mg/l hygromycin, and 30 mg/l kanamycin. After a further 3 weeks, the explants (along with developing shoot buds) were subcultured to MS medium containing 1 mg/l BA, 50 mg/l kanamycin, and 50 mg/l hygromycin for further selection. Transgenic plants were obtained after rooting on half-strength MS medium supplemented with 0.1 mg/l α-naphthaleneacetic acid, 50 mg/l kanamycin, and 50 mg/l hygromycin and were confirmed by GUS histochemical assay and polymerase chain reaction analysis. Genomic Southern blot hybridization confirmed the incorporation of the neomycin phosphotransferase II gene into the host genome.
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Direct somatic embryogenesis and plantlet regeneration from leaf explants of niger, Guizotia Abyssinica (L.f.) Cass.
Indian journal of experimental biology, 2000Co-Authors: H. G. A. Kumar, Hosakatte Niranjana Murthy, V. G. Jadimath, S. S. Sheelavantmath, A. N. Pyati, B. V. RavishankarAbstract:Somatic embryogenesis was induced in niger (Guizotia Abyssinica (L.f.) Cass.) using a simple one step method. Leaf explants were cultured on MS medium with 2,4-D and BAP/Kn individually and in combination. Somatic embryogenesis occurred directly without an intervening callus proliferation phase from subepidermal regions of leaf explants on MS medium supplemented with 2,4-D (2.0 and 5.0 microM) plus Kn/BAP (1.0 and 2.0 microM). Regenerated somatic embryos were successfully grown into whole plants.
Tukaram D. Nikam - One of the best experts on this subject based on the ideXlab platform.
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Influence of osmotic stress, physicochemical factors and nitrogen supplements on embryogenesis and plantlet formation in Guizotia Abyssinica Cass. (Niger)
Indian Journal of Plant Physiology, 2014Co-Authors: S. G. Ghane, Tukaram D. NikamAbstract:An efficient protocol for somatic embryogenesis was developed for the edible oilseed crop Guizotia Abyssinica Cass. (cv. IGP 76). Induction and proliferation of callus was achieved from cotyledonary explants on MS medium amended with 1.5 mg l−1 6-benzyladenine (BA) and 0.5 mg l−1 naphthalene acetic acid (NAA). Several auxin/cytokinin combinations, physical conditions, osmotic stresses and supplementary components, viz., amino acids and casein hydrolysate were tested for induction of embryogenic callus. Higher frequency of embryogenic calli (73.7 %) and somatic embryos per culture (22) were observed on MS + 1.5 mg l−1 BA + 0.5 mg l−1 NAA + 0.5 % NaCl. Histological analyses showed typical globular and other stages of embryo development. The MS medium lacking growth regulators was best for the maximum germination of embryos (53.4 %) and formation of plantlets (65.4 %). Regenerated plantlets were acclimatized and transferred to the field with 62 % survival rate.
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Differential growth, physiological and biochemical responses of niger (Guizotia Abyssinica Cass.) cultivars to water-deficit (drought) stress
Acta Physiologiae Plantarum, 2011Co-Authors: S. G. Ghane, Vinayak H. Lokhande, Tukaram D. NikamAbstract:The present study demonstrates the effect of polyethylene glycol-8000 (PEG) and percent field capacity (FC%)-induced water-deficit stress on growth, water status, productivity and various biochemical parameters in Guizotia Abyssinica Cass. cultivars (IGP 76, GA 10, No. 71 and IGPN 2004) at seedling and maturity stages of the plant. Cultivar GA 10 showed higher, IGP 76 and No. 71 moderate, and IGPN 2004 least reduction in percent seed germination given PEG stress treatments (0, 10 and 20%). A similar pattern was observed for decreased growth and water content of the seedlings and plants of the cultivars exposed to both kinds of water-deficit stresses. The productivity (number of capitula per plant, number of seeds per capitula and 1,000-seed weight) and total chlorophyll content of cultivar IGPN 2004 was significantly higher in comparison to other cultivars given different FC% treatments (100, 80 and 60%). Significantly higher accumulation of proline, glycine betaine and total soluble sugars and lower damage to membrane lipids under increased water-deficit stress (i.e., at 80 and 60% FC) conditions in cultivar IGPN 2004 suggested its more tolerance capacity to water-deficit stress in comparison to other cultivars. Besides, antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase and guaiacol peroxidase) partially demonstrated variations in the tolerance of the cultivars to water-deficit stress. The results suggest that cultivar IGPN 2004 could be considered as more tolerant, and IGP 76 and No. 71 as moderately tolerant, whereas GA 10 was more sensitive to water-deficit stress.
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In vitro plant regeneration from callus of niger (Guizotia Abyssinica Cass.) cv. Sahyadri.
Plant cell reports, 1997Co-Authors: Tukaram D. Nikam, M. G. ShitoleAbstract:Callus formation was achieved with root, hypocotyl, and cotyledon explants of niger (Guizotia Abyssinica Cass.) cultivar Sahyadri on Murashige and Skoog medium containing 0.5 mg l–1β-indoleacetic acid + 1.5 mg l–1 6-benzylaminopurine (BAP). Hypocotyl and cotyledon-derived calli when transferred onto a medium with 0.5 mg l–1 BAP produced an average of 12–32 shoots/ callus culture. The callus retained its potential for shoot regeneration for more than 19 months. The shoots formed an extensive root system and were transferred to pots kept in a greenhouse, where the survival rate was 98%. The plantlets flowered in vitro if transfer to fresh medium or to soil was delayed by 40–50 days. All regenerants were diploid with 2n=30.
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Regeneration of niger (Guizotia Abyssinica Cass.) CV Sahyadri from seedling explants
Plant Cell Tissue and Organ Culture, 1993Co-Authors: Tukaram D. Nikam, M. G. ShitoleAbstract:Root, hypocotyl and cotyledonary explants of niger (Guizotia Abyssinica Cass) CV. Sahyadri were aseptically cultured on Murashige and Skoog's basal medium (MS) containing BAP and kinetin. Multiple shoot regeneration was induced from hypocotyl and cotyledonary explants while root explants produced only callus on MS medium supplemented with BAP. BAP (1 mg l-1) was optimum for shoot regeneration. Regenerated shoots were transferred to MS medium without auxins, with auxins and with increasing concentrations of sucrose for rooting. Complete plantlets were obtained in all cases; however, 0.5 mg l-1 NAA was the best for induction of roots. Ninety-seven per cent of the plantlets survived and completed their life cycle when transferred to natural conditions.
M. G. Shitole - One of the best experts on this subject based on the ideXlab platform.
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In vitro plant regeneration from callus of niger (Guizotia Abyssinica Cass.) cv. Sahyadri.
Plant cell reports, 1997Co-Authors: Tukaram D. Nikam, M. G. ShitoleAbstract:Callus formation was achieved with root, hypocotyl, and cotyledon explants of niger (Guizotia Abyssinica Cass.) cultivar Sahyadri on Murashige and Skoog medium containing 0.5 mg l–1β-indoleacetic acid + 1.5 mg l–1 6-benzylaminopurine (BAP). Hypocotyl and cotyledon-derived calli when transferred onto a medium with 0.5 mg l–1 BAP produced an average of 12–32 shoots/ callus culture. The callus retained its potential for shoot regeneration for more than 19 months. The shoots formed an extensive root system and were transferred to pots kept in a greenhouse, where the survival rate was 98%. The plantlets flowered in vitro if transfer to fresh medium or to soil was delayed by 40–50 days. All regenerants were diploid with 2n=30.
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Regeneration of niger (Guizotia Abyssinica Cass.) CV Sahyadri from seedling explants
Plant Cell Tissue and Organ Culture, 1993Co-Authors: Tukaram D. Nikam, M. G. ShitoleAbstract:Root, hypocotyl and cotyledonary explants of niger (Guizotia Abyssinica Cass) CV. Sahyadri were aseptically cultured on Murashige and Skoog's basal medium (MS) containing BAP and kinetin. Multiple shoot regeneration was induced from hypocotyl and cotyledonary explants while root explants produced only callus on MS medium supplemented with BAP. BAP (1 mg l-1) was optimum for shoot regeneration. Regenerated shoots were transferred to MS medium without auxins, with auxins and with increasing concentrations of sucrose for rooting. Complete plantlets were obtained in all cases; however, 0.5 mg l-1 NAA was the best for induction of roots. Ninety-seven per cent of the plantlets survived and completed their life cycle when transferred to natural conditions.
Jörg-thomas Mörsel - One of the best experts on this subject based on the ideXlab platform.
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Proximate neutral lipid composition of Niger (Guizotia Abyssinica Cass.) seed
Czech Journal of Food Sciences, 2018Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Niger (Guizotia Abyssinica Cass.) seed was extracted with hexane (H) and chloroform/methanol (CM) (2:1, v/v) to determine the effect of the solvent on the amount and composition of the recovered lipid. The amount of the total lipid (TL) extracted with H was 29.6% of the seed weight, while that extracted with CM was 49.9%. Column and thin-layer chromatographic procedures on Silica Gel were performed to fractionate the main neutral lipid (NL) subclasses. Fatty acid composition of the NL subclasses, triacylglycerol (TAG) molecular species, and sterol (ST) content were estimated. The NL amount was found to be higher (97% of TL) in the H extract than in the CM extract (93% of TL). TAG appeared to be the predominant NL subclass (89.7-91.9% of total NL). Linoleic acid (C18:2n-6) was the main fatty acid followed by oleic acid (C18:1n-9) as the second main unsaturated fatty acid, while palmitic acid (C16:0) was the major saturated fatty acid. With high temperature gas-liquid chromatography using a flame ionization detector (HTGLC/FID) and H 2 as the carrier gas, the actual TAG molecular species according to their carbon numbers were separated. TAG of even carbon numbers 16 and 18 were contained in six TAG molecular species. The major peaks occured at C54:6, and C54:3 corresponding to trilinolein and triolein. Furthermore, TAG molecular specie, expected to contain two molecules of linoleic acid (C54:5), was detected in a high level. Phytosterol pattern was determined without derivatization in the unsaponifiable fractions by HTGLC/FID. ST profile was characterized by a high total amount accounting for 4.22 g/kg of total H extract, and 4.00 g/kg of total CM extract. β-Sitosterol (2.035-1.929 g/kg TL) was the main component in both extracts. The major ST found were, in order of decreasing prevalence, β-sitosterol > campesterol > stigmasterol > A5-avenasterol > Δ7-avenasterol >lanosterol.
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oxidative stability of black cumin nigella sativa l coriander coriandrum sativum l and niger Guizotia Abyssinica cass crude seed oils upon stripping
European Journal of Lipid Science and Technology, 2004Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Information on stability of edible oils is important for predicting the quality deterioration of the oil during storage and marketing. Stripping of crude oils removes most of non-triacylglycerol components, including polar lipids and phenolics. Oxidative stability of black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.) and niger (Guizotia Abyssinica Cass.) crude and stripped seed oils was investigated and compared. The factors influencing the oxidative stability of different seed oils were also discussed. Oil samples were stored under accelerated oxidation conditions for 21 d. The progress of oxidation at 60 °C was followed by recording the ultraviolet absorptivity and measuring the formation of oxidative products (peroxide and p-anisidine values). Inverse relationships were noted between peroxide values and oxidative stabilities and also between secondary oxidation products, measured by p-anisidine value and stabilities at termination of the storage. Absorptivity at 232 nm and 270 nm increased gradually with the increase in time, due to the formation of conjugated dienes and polyenes. In general, oxidative stabilities of crude oils were stronger than their stripped counterparts and the order of oxidative stability was as follows: coriander > black cumin > niger seed. Levels of polar lipids in crude oils correlated with oxidative stability. Thus, the major factor that may contribute to the better oxidative stability of crude oils was the carry-over of their polar lipids.
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Determination of the lipid classes and fatty acid profile of Niger (Guizotia Abyssinica Cass.) seed oil
Phytochemical analysis : PCA, 2003Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Niger seeds (Guizotia Abyssinica Cass.), which are of interest as a new source of vegetable oils, were subjected to Soxhlet-extraction with n-hexane and the extract analysed using a combination of CC, GC, TLC and normal-phase HPLC. The total lipid content was ca. 300 mg/g seed material, and the fatty acid profile showed a high content of linoleic acid (up to 63%) together with palmitic acid (17%), oleic acid (ca. 11%), and stearic acid (ca. 7%). CC separation over silica gel eluted with solvents of increasing polarity yielded 291 mg/g of neutral lipids, 5.76 mg/g of glycolipids, and 0.84 mg/g of phospholipids. GC analysis showed that the major fatty acid present in all lipid classes was linoleic acid together with minor amounts of palmitic, oleic and stearic acids. Polar lipid fractions, however, were characterised by higher levels of palmitic acid and a lower content of linoleic acid. Phospholipid classes separated by normal-phase HPLC consisted of phosphatidylcholine (ca. 49%), phosphatidylethanolamine (22%), phosphatidylinositol (14%), phosphatidylserine (ca. 8%), and minor amounts (2-3%) of phosphatidylglycerol and lysophosphatidylcholine.
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analysis of glycolipids from black cumin nigella sativa l coriander coriandrum sativum l and niger Guizotia Abyssinica cass oilseeds
Food Chemistry, 2003Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Abstract Edible plant glycolipids (GL) are anticipated to play a role in human nutrition. Total glycolipids (TGL) were separated from black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.) and niger (Guizotia Abyssinica Cass.) seed oils by silica gel chromatography. Different GL subclasses were then identified and separated using high-performance liquid chromatography with ultraviolet adsorption (HPLC/UV). Separation was accomplished using Zorbax-Sil (5 μm) column with an isocratic elution by mixed solvents of isooctane/2-propanol (1:1, v/v) and detection at 206 nm. Methods are described for the analysis of GL constituents, sugar and sterols (ST), using gas–liquid chromatography equipped with flame ionization detector (GLC/FID). A relatively high level of TGL was found in all studied oilseeds. Six GL subclasses were detected in black cumin seed oil, wherein diglucosyldiacylglycerol (DGD) was the prevalent component, followed by glucocerebroside (CER). Among the TGL from coriander and niger oilseeds, acylated steryl glucoside (ASG), steryl glucoside (SG) and CER were detected. The fatty acid profiles of GL fractions from black cumin and niger seed oils was generally similar, wherein linoleic acid C18:2n-6 was the dominating fatty acid, followed by oleic acid C18:1n-9. Petroselinic acid C18:1n-12 was the fatty acid marker in GL subclasses obtained from coriander seed oil, followed by linoleic acid C18:2n-6. Four ST moieties were identified in black cumin and coriander SG and ASG fractions, while the fractions from niger oilseeds showed only three distinct ST peaks. As component sugar, glucose was the only sugar detected in all samples.
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Phospholipid composition of niger (Guizotia Abyssinica cass.) seed oil
LWT - Food Science and Technology, 2003Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Niger (Guizotia Abyssinica Cass.) seeds were extracted with chloroform/methnol (2:1, v/v) and total lipid content was 49.9% of seed weight. The major fatty acid was linoleic acid followed by oleic acid as a second unsaturated fatty acid. Palmitic acid was the major saturated fatty acid followed by stearic acid. Column chromatography with solvent of increasing polarity yielded 93.0% neutral lipids, 4.90% glycolipids and 0.60% phospholipids (PL). Polar lipids were characterized by higher palmitic acid and lower linoleic acid levels. PL subclasses were separated via high-performance liquid chromatography (HPLC). The major individual PL subclasses were found to be phosphatidylcholine followed by phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine, respectively. Phosphatidylglycerol and lysophosphatidylcholine, on the other hand, were detected in smaller quantities. The predominant PL-bound fatty acids presented were linoleic, palmitic and oleic acids.
Mohamed Fawzy Ramadan - One of the best experts on this subject based on the ideXlab platform.
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Proximate neutral lipid composition of Niger (Guizotia Abyssinica Cass.) seed
Czech Journal of Food Sciences, 2018Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Niger (Guizotia Abyssinica Cass.) seed was extracted with hexane (H) and chloroform/methanol (CM) (2:1, v/v) to determine the effect of the solvent on the amount and composition of the recovered lipid. The amount of the total lipid (TL) extracted with H was 29.6% of the seed weight, while that extracted with CM was 49.9%. Column and thin-layer chromatographic procedures on Silica Gel were performed to fractionate the main neutral lipid (NL) subclasses. Fatty acid composition of the NL subclasses, triacylglycerol (TAG) molecular species, and sterol (ST) content were estimated. The NL amount was found to be higher (97% of TL) in the H extract than in the CM extract (93% of TL). TAG appeared to be the predominant NL subclass (89.7-91.9% of total NL). Linoleic acid (C18:2n-6) was the main fatty acid followed by oleic acid (C18:1n-9) as the second main unsaturated fatty acid, while palmitic acid (C16:0) was the major saturated fatty acid. With high temperature gas-liquid chromatography using a flame ionization detector (HTGLC/FID) and H 2 as the carrier gas, the actual TAG molecular species according to their carbon numbers were separated. TAG of even carbon numbers 16 and 18 were contained in six TAG molecular species. The major peaks occured at C54:6, and C54:3 corresponding to trilinolein and triolein. Furthermore, TAG molecular specie, expected to contain two molecules of linoleic acid (C54:5), was detected in a high level. Phytosterol pattern was determined without derivatization in the unsaponifiable fractions by HTGLC/FID. ST profile was characterized by a high total amount accounting for 4.22 g/kg of total H extract, and 4.00 g/kg of total CM extract. β-Sitosterol (2.035-1.929 g/kg TL) was the main component in both extracts. The major ST found were, in order of decreasing prevalence, β-sitosterol > campesterol > stigmasterol > A5-avenasterol > Δ7-avenasterol >lanosterol.
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Functional properties, nutritional value, and industrial applications of Niger Oilseeds (Guizotia Abyssinica Cass.).
Critical reviews in food science and nutrition, 2012Co-Authors: Mohamed Fawzy RamadanAbstract:Non-conventional seeds are being considered as novel food because their constituents have unique chemical properties and may augment the supply of nutritional and functional products. Niger (Guizotia Abyssinica Cass.) seed and its crude oil have been widely used in traditional nutritional and medicinal applications. Consequently, niger seed has been extensively studied for its nutritional value, biological activities, and antioxidative properties. In consideration of their potential utilization, detailed knowledge on the composition of niger oilseeds is of major importance. The diversity of applications to which niger seed can be put gives this oilseed great industrial importance. This review summarizes the nutritional value, functional properties, and industrical applications of niger seeds.
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oxidative stability of black cumin nigella sativa l coriander coriandrum sativum l and niger Guizotia Abyssinica cass crude seed oils upon stripping
European Journal of Lipid Science and Technology, 2004Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Information on stability of edible oils is important for predicting the quality deterioration of the oil during storage and marketing. Stripping of crude oils removes most of non-triacylglycerol components, including polar lipids and phenolics. Oxidative stability of black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.) and niger (Guizotia Abyssinica Cass.) crude and stripped seed oils was investigated and compared. The factors influencing the oxidative stability of different seed oils were also discussed. Oil samples were stored under accelerated oxidation conditions for 21 d. The progress of oxidation at 60 °C was followed by recording the ultraviolet absorptivity and measuring the formation of oxidative products (peroxide and p-anisidine values). Inverse relationships were noted between peroxide values and oxidative stabilities and also between secondary oxidation products, measured by p-anisidine value and stabilities at termination of the storage. Absorptivity at 232 nm and 270 nm increased gradually with the increase in time, due to the formation of conjugated dienes and polyenes. In general, oxidative stabilities of crude oils were stronger than their stripped counterparts and the order of oxidative stability was as follows: coriander > black cumin > niger seed. Levels of polar lipids in crude oils correlated with oxidative stability. Thus, the major factor that may contribute to the better oxidative stability of crude oils was the carry-over of their polar lipids.
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Determination of the lipid classes and fatty acid profile of Niger (Guizotia Abyssinica Cass.) seed oil
Phytochemical analysis : PCA, 2003Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Niger seeds (Guizotia Abyssinica Cass.), which are of interest as a new source of vegetable oils, were subjected to Soxhlet-extraction with n-hexane and the extract analysed using a combination of CC, GC, TLC and normal-phase HPLC. The total lipid content was ca. 300 mg/g seed material, and the fatty acid profile showed a high content of linoleic acid (up to 63%) together with palmitic acid (17%), oleic acid (ca. 11%), and stearic acid (ca. 7%). CC separation over silica gel eluted with solvents of increasing polarity yielded 291 mg/g of neutral lipids, 5.76 mg/g of glycolipids, and 0.84 mg/g of phospholipids. GC analysis showed that the major fatty acid present in all lipid classes was linoleic acid together with minor amounts of palmitic, oleic and stearic acids. Polar lipid fractions, however, were characterised by higher levels of palmitic acid and a lower content of linoleic acid. Phospholipid classes separated by normal-phase HPLC consisted of phosphatidylcholine (ca. 49%), phosphatidylethanolamine (22%), phosphatidylinositol (14%), phosphatidylserine (ca. 8%), and minor amounts (2-3%) of phosphatidylglycerol and lysophosphatidylcholine.
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analysis of glycolipids from black cumin nigella sativa l coriander coriandrum sativum l and niger Guizotia Abyssinica cass oilseeds
Food Chemistry, 2003Co-Authors: Mohamed Fawzy Ramadan, Jörg-thomas MörselAbstract:Abstract Edible plant glycolipids (GL) are anticipated to play a role in human nutrition. Total glycolipids (TGL) were separated from black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.) and niger (Guizotia Abyssinica Cass.) seed oils by silica gel chromatography. Different GL subclasses were then identified and separated using high-performance liquid chromatography with ultraviolet adsorption (HPLC/UV). Separation was accomplished using Zorbax-Sil (5 μm) column with an isocratic elution by mixed solvents of isooctane/2-propanol (1:1, v/v) and detection at 206 nm. Methods are described for the analysis of GL constituents, sugar and sterols (ST), using gas–liquid chromatography equipped with flame ionization detector (GLC/FID). A relatively high level of TGL was found in all studied oilseeds. Six GL subclasses were detected in black cumin seed oil, wherein diglucosyldiacylglycerol (DGD) was the prevalent component, followed by glucocerebroside (CER). Among the TGL from coriander and niger oilseeds, acylated steryl glucoside (ASG), steryl glucoside (SG) and CER were detected. The fatty acid profiles of GL fractions from black cumin and niger seed oils was generally similar, wherein linoleic acid C18:2n-6 was the dominating fatty acid, followed by oleic acid C18:1n-9. Petroselinic acid C18:1n-12 was the fatty acid marker in GL subclasses obtained from coriander seed oil, followed by linoleic acid C18:2n-6. Four ST moieties were identified in black cumin and coriander SG and ASG fractions, while the fractions from niger oilseeds showed only three distinct ST peaks. As component sugar, glucose was the only sugar detected in all samples.