Variation in the Composition and Quality of Nigella sativa L. Seed Oils-The Underestimated Impact on Possible Health-Promoting Properties.

Nigella sativa L. (black cumin) is one of the most investigated medicinal plants in recent years. Volatile compounds like thymoquinone and unsaponifiable lipid compounds are crucial functional components of this oil. Unfortunately, the composition of oils and their quality indicators are ambiguous both in terms of identified compounds and value ranges. Thirteen oils were extracted with hexane from black cumin seeds grown in India, Syria, Egypt, and Poland and analyzed for their fatty acid composition, unsaponifiable compound content and volatile compounds. Oils were also subjected to quality tests according to standard methods. The fatty acid composition and sterol content/composition were relatively stable among the tested oils. Tocol content varied in the range of 140-631 mg/kg, and among them, ß-tocotrienol and γ-tocopherol prevailed. Oils' volatile compounds were dominated by seven terpenes (p-cymene, α-thujene, α-pinene, ß-pinene, thymoquinone, γ-terpinene, and sabinene). The highest contents of these volatiles were determined in samples from Poland and in two of six samples from India. High acid and peroxide values were typical features of N. sativa L. oils. To sum up, future research on the medicinal properties of black cumin oil should always be combined with the analysis of its chemical composition.

Impact of the addition of 4-vinyl-derivatives of ferulic and sinapic acids on retention of fatty acids and terpenoids in cold-pressed rapeseed and flaxseed oils during the induction period of oxidation.

In the western diet there is an oversupply of n-6 fatty acids. This adverse trend can be balanced by the consumption of rapeseed and flaxseed oils rich in α-linolenic acid (n-3). However, the high share of this fatty acid contributes to low oxidative stability of oil. Oxidation decreases n-3 fatty acid and other bioactive compounds contents, which adversely affects oil nutritional value. In this study, the impact of ferulic and sinapic acids vinyl derivatives on the fatty acids and oil terpenoids (sterols, tocols, carotenoids, squalene) retention at the end of induction period during accelerated oxidation of rapeseed and flaxseed cold-pressed oils was investigated. It was found that the use of 4-vinylsyringol (4-VS) or 4-vinylquaiacol (4-VQ) increased the retention of intact sterols and carotenoids (at least 2-fold) and squalene (at least 4-fold). The 4-VQ addition also inhibited the α-linolenic acid loss. Unfortunately, both phenolic derivatives favoured α-tocopherol decay in rapeseed oil.

Supercritical CO2 extraction in chia oils production: impact of process duration and co-solvent addition.

This study was conducted to show impact of supercritical fluid extraction using pure SC-CO2 or SC-CO2 enriched by 2, 6, and 10% of acetone, simultaneously varied by the extraction time (1 vs. 5 h), on the quality of chia seed oils. Obtained oils were relatively similar in the fatty acid composition, but they differed in total content of phytochemicals (from 4956 to 6391 mg/kg of oil). Among them, three oils were the most different: oil extracted 1 h with pure SC-CO2 (the most abundant in squalene, sterols, and tocopherols), oil extracted 5 h with pure SC-CO2 (the poorest in squalene, polyphenols, and carotenoids, with medium level of sterols and tocopherols) and oil extracted 1 h with SC-CO2 enriched by 10% acetone (the most abundant in polyphenols and carotenoids). Such unique chia oils can be valuable for special market needs, such as cosmetics, pharmaceuticals, functional food or diet supplement production.

Comparison of the effect of sinapic and ferulic acids derivatives (4-vinylsyringol vs. 4-vinylguaiacol) as antioxidants of rapeseed, flaxseed, and extra virgin olive oils.

The aim of the work is to compare the antioxidant activity of 4-vinylguaiacol (4-VQ) and 4-vinylsyringol (4-VS) added to stabilize three (flaxseed, olive and rapeseed) commercial oils. The phenolics were added at concentration of 20, 40 and 80mg per 100g of oil. The oils were oxidized in a Rancimat test at 110°C. The linear dependences between the concentrations of each of these compounds and the induction period (IP) were found. Generally, 4-VQ was more effective, since the determined IP increase after its addition was from 5 to 25-fold higher than for the same addition of 4-VS. The highest increase was noted for flaxseed oil, for which 80mg 4-VQ addition per 100g of oil resulted in 50% IP increase. The highest absolute values of IP were reached by extra virgin olive oil, naturally abundant in phenolic compounds and with the lowest fatty acids oxidation index.

Sensory, Physico-Chemical and Water Sorption Properties of Corn Extrudates Enriched with Spirulina.

This study compares the quality of extrudates made from corn grits with the addition of up to 8% of spirulina powder. The sensory properties (shape, color, aroma, taste and crispness), chemicals (content of water, protein, fat, ash, fiber, carbohydrates, carotenoids, chlorophyll and phycocyanin) and physical properties (color, water absorption index, expansion indices, texture and water sorption properties) were determined. It has been found that spirulina-enriched extrudates had slightly lower sensory scores, but the addition of spirulina improved their nutritional value. The contents of protein, ash, fiber and ß-carotene increased in extrudates with 8% of spirulina by 34, 36, 140 and 1,260%, respectively. The increasing addition of spirulina caused a decrease in extrudates lightness, an increase in their greenness and yellowness accompanied by a decrease of expansion indices and an increase of softness. Only small differences were found in water sorption properties, suggesting a similar behavior of spirulina-enriched extrudates during storage.

Effect of Sea-Buckthorn (Hippophaë rhamnoides L.) Pulp Oil Consumption on Fatty Acids and Vitamin A and E Accumulation in Adipose Tissue and Liver of Rats.

An in vivo experiment was conducted to determine the effect of sea-buckthorn pulp oil feeding on the fatty acid composition of liver and adipose tissue of Wistar rats and the liver accumulation of retinol, its esters and α-tocopherol. For a period of 28 days, rats were given a modified casein diet (AIN-93) in which sea-buckthorn pulp oil, soybean oil and pork lard were used as sources of fat. Compared to the other fat sources, sea-buckthorn pulp oil was the most abundant in C16 fatty acids, carotenoids (mainly ß-carotene) and tocopherols (mainly α-tocopherol). Its consumption was reflected in an increased share of palmitoleic acid in adipose tissue and the liver and an increased level of retinol in liver tissues (this was not observed for its esters). Although the type of fat did not have a significant effect on the average content of α-tocopherol in the liver, the variation of saturation of this tissue with α-tocopherol was the lowest when rats were fed a diet containing sea-buckthorn oil. This experiment indicates the possibility of affecting adipose tissue and liver by a diet.

Comparison of the phenolic compounds, carotenoids and tocochromanols content in wheat grain under organic and mineral fertilization regimes.

A field study was performed to evaluate the effect of mineral (NPK) and organic-based fertilizers such as compost (C), manure (FYM) and meat and bone meal (MBM) on the appearance (dimensions and color) of spring wheat kernels and on the total content in grain of main its phytochemicals (polyphenols, carotenoids and tocochromanols) and phenolic acids composition. Total phenolic compounds were determined using the Folin-Ciocalteu assay after alkaline hydrolysis of grain and carotenoids were analyzed spectrophotometrically. Composition of tocochromanols and phenolic acids was determined using RP-HPLC techniques. Only insignificant differences in the appearance of kernels and small changes in the content and composition of grain phytochemicals were noted between the studied fertilization systems. Among the analyzed phytochemicals the greatest variation was observed in the group of polyphenol compounds, with a stated increase of their total content of 6.7 and 11.2% in grain fertilized with MBM and compost, respectively. Simultaneously the grain from organic fertilization contained significantly less phenolic acids, and the decrease in their content ranged from 10.0% for FYM to 24.8% for MBM+EM-1. Organically and conventionally fertilized grain had similar amounts of tocochromanols and carotenoids. Comparison of MBM and MBM+EM-1 variants showed that application of effective microorganisms decreased carotenoids and tocochromanols content by 8.5 and 9.7%, respectively.