جستجوی مقالات مرتبط با کلیدواژه « اسید چرب » در نشریات گروه « زیست شناسی »

Citrus aurantium L. seed is a by-product of fruit juice industries. In this research, the main fatty acids and phytosterols in C. aurantium seed oil were evaluated with the aim of nutritional evaluation and its biological properties. The C. aurantium oil extracted by two methods of cold pressing and using hexane solvent.The C. aurantium seed fatty acids composition was analyzed by GC-MS, 1HNMR, and 13CNMR. In addition, the effects of ultrasonic waves and air pressure on the C. aurantium pulp obtained from cold press extraction by n-hexane was studied. The findings showed that the highest oil yields were obtained using ultrasound-assisted extraction (25%) compared to other methods. The five fatty acids including 9-oleic (18.07%), Linoleic (36.69%), palmitic (21.90%), stearic acid (6.6%) and 10-oleic acids (1.1%) were the most phytosterols in C. aurantium seed oil. According to the obtained results, C. aurantium oil can be considered as a new food source.

Dragon's head, one of the mint family plants with 30% oil and mucilage in its seeds. In order to evaluate the response of plant to nitrogen fertilizers in saline soils, a factorial experiment was conducted based on randomized complete block design with three replications in 2018 at Urmia University. Treatments included nitrogen fertilizer (urea, Azotobacter as a foliar application and Azotobacter as a seeds inoculant and no-fertilizer as control), and two planting bed, saline and normal, with conductivity of 6.7 and 0.91 ds/m respectively. The highest amount of catalase, ascorbate peroxidase and activity total phenol content wasto plants grown under saline soil without any nitrogen fertilizer. However, their values decreased significantly for all fertilizer treatments. All constituents of seed mucilage were higher in non-saline conditions. While application of urea increased rhamnose content, Azotobacter inoculation caused xylose, glucose and galactose content to be increased under non-saline condition. Urea was preferred for the production of raffinose, arabinose, galacturonic acid and glucuronic acid. Salinity, likewise fertilizer treatments had no significant effect on oil content and mucilage. In all treatments, salinity increased the antioxidants, which was related to plant response to stress conditions. In the case of soluble sugars, nitrogen fertilizers prevented excessive reduction and moderated this amount. Despite increasing saturated and unsaturated fatty acids under soil salinity, fertilizer treatments increased the saturated fatty acids (stearic, palmitoleic, palmitic and myristic) against decreasing unsaturated fatty acids (linolenic, linoleic and oleic).

In this study, some of the growth parameters and biochemical composition of Chaetoceros muelleri were investigated under blue, white, and red light. Different treatments of lights applied to Chaetoceros muelleri cultures (salinity 25 ppt, temperature 23 ± 1°C, light intensity 1500 ± 200 lux, Light/Dark 12/12, mild aeration, alkalinity 7.5-8.5( for 12 days in divided Indoor chambers. The microalgae under blue light showed the highest cell density, specific growth rate, chlorophyll a, dry weight, protein, omega-3 fatty acids, palmitoleic acid (C16:1), and the shortest doubling time, low fat and omega-6 were observed. The lowest cell density, dry weight, chlorophyll a, protein, omega-3 fatty acids, oleic acid (C18: 1), and more than 25% palmitic acid (C16: 0) were observed under red light. The highest doubling time of the population, the highest amount of omega-6 fatty acids and oleic acid (C18: 1), was observed in white light. The total fat content was not significantly different between the three light ones (p <0.05). Red light accounted for more than 41% of the SFA value, white light more than 16% of PUFA, and light blue 46% of MUFA. Blue light clearly showed better performance and had a significant difference (0.05 pp) compared to white and red while there was no significant difference between white and red.

In the present study, DPPH free radical scavenging activity, metal chelating activity, reduction power, total phenolic content, pigments content, and fatty acid profile of Dunaliella salina microalgae were investigated. Solvents of methanol, hexane and chloroform in the algae extract concentrations of 0.01, 0.1, and 1 µg/ml was used. The results showed that the highest scavenging of DPPH free radicals was in the methanol extract, and the minimum value was observed in 0.01 hexane extract (p<0.05). Maximum phenolic contents were found in the concentration of 1 µg of methanol extract and the minimum in 0.01 µg hexane extract. Maximum iron reduction power in methanol and chloroform extracts at a concentration of 1 µg and the minimum concentration of 0.01 μg of hexane extract was measured (p<0.05). The carotenoids and the chlorophyll b have the highest and lowest content, respectively (p<0.05). The study of the fatty acid composition of Dunaliella saline showed that the palmitic acid, palmitoleic acid, and alpha-linolenic acid were the highest saturated, monoenoic, and polyunsaturated fatty acids respectively. The results of this study have investigated that the concentration factor had a significant effect on the antioxidant properties of Dunaliella salina algae. The methanol extract had the best efficiency of Donalilla salina microalgae metabolite extraction.

Manipulation in the concentration of the nutrients of microalgae is one of the effective strategies to improve biomass and nutritional value. In this study, the effect of different concentrations of cobalt (0.001, 0.01 (control), 0.1, 1 and 10mg/L) on cell density, chlorophyll a and b, lipid, fatty acid profile, iodine and soap numbers of Isochrysis galbana were studied for two weeks. Adding 0.001 mg/L cobalt significantly improved chlorophyll a (3.2118mg/L) and b (2.001mg/L) and lipid (24.09%) and protein (53.91%) content of I. galbana compared to other treatments (P<0.05). The highest level of saturated fatty acid (47.83%) was observed in 10mg/L cobalt treatment, while the reduction of cobalt to 0.001mg/L caused an increase in monounsaturated fatty acid (MUFA) and polyunsaturated fatty acids (PUFA). Also, the maximum and minimum iodine and soap numbers were observed at concentrations of 0.001 and 10mg/L cobalt, respectively. Overall, a concentration of 0.001 mg/L cobalt provided the nutritional value of this microalgae in terms of chlorophyll a and b, protein, lipid and PUFA, although an alteration in the optimal concentration had a negative effect on biomass.

The effects of Iron (Fe+2), copper (Cu+2) and zinc (Zn+2) trace elements on lipid and fatty acids of microalgae Spirulina platensis were investigated under laboratory conditions. The specimen cultured in Zarrouk media with 4 groups including control and 3 different concentrations of iron, zinc and copper trace elements with the volume of 10 times compare to control. Maximum and minimum of lipid contents were measured in iron and zinc treatments with 5.28 and 1.47% dry weight, respectively. The major group of fatty acids were C16:00, C18:00, C16:1n7, C18:1n9, C18:2n6 and C18:3n3. Maximum and minimum saturated fatty acids (SFA) were measured in iron and zinc treatments with 43.50 and 37.54 mg.g-1.dw-1, respectively. The highest value of mono and poly unsaturated fatty acids (MUFA and PUFA) were determined in zinc and iron treatments (53.19 and 39/51 mg g-1 dw-1), respectively, compared with other treatments. In conclusion, zinc treatment increased the contents of EPA, DHA, MUFA and omega 6 as compared to other treatments and the highest amount of PUFA was obtained in iron treatment.

Phosphorus one of the critical macronutrient that plays an important role in energy transfer, phospholipid and nucleic acids synthesis and biochemical compounds in microalgae cells, as well as plays an important role in the formation and transfer of metabolic energy in ATP and NADP. In this study, the effect of different phosphorus concentration (0, 2, 4, 8 and 16 mg/L) on growth rate and biochemical composition of Isochrysis galbana was investigated. The results showed phosphorus deprivation decreased cell growth, pigments and protein; while carbohydrate and lipid content of I. galbana increased as the phosphorus concentration increased. The highest carbohydrate, protein and lipid content were 23.5, 34.6 and 36.2 % in phosphorus concentrations of 0, 8, 0 mg/L, respectively. Also, by increasing the concentration of phosphorus from 0 to 16 mg/l, the content of C16: 0 (33.96%) and C18: 0 (23.4%) decreased to 27.75% and 14.37%, respectively. The results of this study indicate that phosphorus concentration significantly affects the growth rate and biochemical compositions of I. galbana.

In this study, examines oil percentage and fatty acid composition of Silybum marianum seeds were determined in habitats located in the west of Mazandaran province at different elevations and soil physiochemical properties. After identifying Silybum marianum shrubs in elevation classes of the study area, seeds were sampled using systematic random method and along a 100 m transect at 30 m intervals from three points. After the establishment of transects, in order to study soil physiochemical properties and their relationships with the quantity and quality of fatty acids and oil, three plots were placed in each site and as the number of plant samples, 18 soil samples were taken from the depth of 30 cm and around the root of the plant. Hexane solvent and Soxhlet were used to determine oil content. Identifying fatty acid compositions and Silymarin extraction were done using gas chromatography spectrometer (GC/MS) and methanol solvent in ultrasonic bath, respectively. Based on the results, the highest amount of oil and Silymarin were obtained from plains and mountainous regions, respectively. According to the results, unlike Silymarin, habitat did not have a significant effect on oil content, also the highest amount of oil and Silymarin were obtained from plains and mountainous regions, respectively. Considering the significant effect of habitat on the quality of oil, Oleic acid showed significant negative response to habitat. Soil organic matter and calcium carbonate also had negative inverse relationships with elevation. Sand, potassium, phosphorus and nitrogen indicated negative relationship with oil percentage. Elevation had positive relationship with Margaric acid and Linoleic acid, but negative relationship with Oleic acid. There was positive relationship between Palmitic acid and sand, phosphorus and nitrogen. Because the Oleic acid was predominant followed by the Linoleic acid, it can be concluded that Silybum marianum oil is in the Oleic-Linoleic oil group with high nutritional quality, thus cultivation of this oily seed could be an alternative to produce edible oil and reduce the dependence on other countries.

Water stress is one of the limiting factors of plant growth. In order to investigate the effect of chitosan and nano-chitosan on Nigella sativa L. under drought stress, a split plot experiment based on randomized complete block design was conducted in research Field of Islamic Azad University Arak Branch in 2016. The main plots consisted of spraying with chitosan, nano-chitosan and water as control and the sub plots consisted of cultivars Arak, Azerbaijan, Semirom, Yasuj and Torbat-e-Heydariyeh. Irrigation was performed regularly from the beginning of planting until flowering stage and then stopped and spraying was achieved. After 80% emergence of floret, plots were sampled and number of secondary branches, capsules per plant, plant height, 1000 seed weight and oil percentage were evaluated. Percentages of oil and fatty acids were measured by gas chromatography.Experimental results were showed that drought stress reduced the components of black cumin yield but improved qualitative factors such as oil and fatty acids percentage. The highest and lowest seed oil content was in Azarbaijan (28.76%) and Semirom (26.39%), respectively. Yasuj can be considered as a drought tolerant cultivar due to its high content of capsules, 1000-grain weight and weight/m2. The effect of nano-chitosan in moderating stress-induced effects was better than chitosan. Azerbaijan and Semirom cultivars had the highest amount of oleic acid (Omega 9), Yasuj cultivar had the highest amount of linoleic acid (Omega 6) and Torbat Heydariyeh and Arak cultivars had the highest amount of linoleic acid (Omega 3).

Nowadays, brown macroalgae are considered to be a source of various nutritional and pharmaceutical compounds. In addition, fish roe is very susceptible to spoilage due to its high amount of protein and unsaturated fatty acids. In order to postpone the deterioration of roe-related products, salt and preservatives are utilized. Natural preservatives are recommended because of the adverse effects of chemical additives. Thus, different concentrations of pure alginate (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) were chose and then the 0.2% alginate was selected on the basis of the sensory evaluation of the results. Moreover, the treatments including control (salt-alginate-free), A1 (containing 2.5% salt) A2 (containing 0.2% alginate), A3 (containing 2.5% salt and 0.2% alginate) were used to investigate their preservative effects on fish roe. The quality of rainbow trout roe was assessed within 0, 15, 30, 45 days at refrigerated storage. The treatment A3 showed significant differences in microbial, chemical and sensory results compared with other treatments (p≤0.05). According to the results, salting 2.5% and alginate 0.2% method gave good flavor and increased shelf life to the roe.

Because of the importance of identifying the native genotypes and selecting the appropriate cultivars for successful development of olive tree cultivation, the present study was conducted to evaluate the selected oil and table genotypes compatible with climatic conditions of Gorgan. The experiment was done in a completely randomized design with three replications on 24 genotypes in Hashemabad complex in Golestan province. The maturity index of fruit was measured according to a method suggested by International Olive Oil Council and the percentage of oil was determined using a soxhlet method. Six genotypes with higher percentage of oil were selected and the physicochemical properties of the oil and the percentage of fatty acids were determined. Results showed that the highest and lowest fruit weights were observed in genotypes I7 and E6, respectively. The highest percentage of fruit flesh was observed in I7. E11 and D5 had the highest percentages of oil in dry and fresh matter. The lowest acidity was observed in B7 and the lowest peroxide was seen in E11. Genotypes F1 and E11 had the highest oil phenolic compounds. A10 showed the highest amounts of chlorophylls and carotenoids. F9 had the lowest indexes of K232 and K270 and following that A10 had the lowest index of K270. The highest percentage of oleic acid and the lowest percentage of linoleic acid were observed in A10. Genotype B7 had the lowest percentage of palmitic acid. Due to fruit weight, percentage of flesh and fruit sphericity, eight table genotypes were selected for further study. Among the selected table genotypes, genotype I7 had the highest levels of flavonoids, phenolic compounds, antioxidants, and anthocyanin. According to the results, the best oil genotypes were A10 and E11, the best table genotype was I7 and the best dual-purpose genotypes were F10 and B7.

This study aimed to investigate the fatty acid composition of zooplankton and common carp larvae in hatcheries at the first seven days of larval rearing. SFA was higher in rotifers before releasing of larvae on = day 1 gain (6.15%), compared to that of day 7, and significantly decreased in the rate of 3.53%. On day 7, total amount of MUFA was increased significantly. Oleic acid was the most dominant monounsaturated fatty acid in all treatments except day 1 and showed the higher amount day 5. . The highest PUFA concentration was on day 7 with 52.27% and the lowest level was on day 4 with 42.92. The rotifer PUFA was significantly lower in that that of larvae before releasing. At the end of the experiment, total amount of PUFA increased of in the rate of 5.16%. The amount of omega 6, linoleic acid, arachidonic acid and acid was higher in the body of larvae compared to rotifer. However their values were increased at the end of the experiment. The levels of EPA and DHA were higher in rotifers compared to those in fish larvae on day before the larval releasing. The results of this study indicated that rotifer is a rich source of fatty acids for food for developing fish larvae. MUFA levels was lower in rotifer than the larvae. Similar to SFA, MUFA levels decreased significantly in the rate of 1.79% from day 1 to day 7.

Fatty acids accumulation pattern and oil oxidizability during fruit ripening of two olive cultivars of high and low oleic acid, Shengeh and Mary,were studied respectively while the environmental conditions kept constant. Samplings were done at 90, 120, 150 and 180 days after flowering (DAF) and the fatty acid composition was determined by gas chromatography (GC) after seed oil extraction by n-hexane. Analysis of variance (ANOVA) showed that accumulation of stearic, oleic and linoleic acids were significantly influenced by genotype. Indeed, there was a significant correlation between time andboth oleic and linoleic acids. Overall measurements demonstrated higher palmitic and linoleic acids in Shengeh cv. and higher steraric and oleic acids in Mari cv. During four studied stages olive development . Also, there was a positive correlation between linoleate and calculated oxidizability value (COX). Increasing pattern of oleic acid content in both genotypes implies the inhibitory effect of oleic acid on the phospholipase activity of oleosins leading prevention in out-course germination It is worthy to note that genotype plays a crucial role in fatty acid content in development stages as seed oli acid content in mary cv. is higher then Shengeh.

Oils extracted from colza have high nutrition quality. Cultivation of modified species with low level of undesired components, have been developed recently in Iran. Rapeseed species modified by genetic engineering have been cultivated all around the world. In current study, recombinant genes have been detected in seven species of colza which are used in oil industries. Moreover, fatty acid profiles of oils extracted from these seeds have been analyzed. DNA extracted by CTAB method, and quality of the extracted DNAs were assessed by PCRs with chloroplast tRNA primer. Presence of transgenic colza were assessed with three gene sequences of CaMv 35s promoter, NOS terminator and nptII marker. The results showed that NOS terminator and CaMv 35s promoter sequences found in none of samples, while the 215 bp electrophoretic band due to PCR product of nptII sequence has seen in four seeds out of seven samples. Analysis of fatty acid profiles showed that GM modification has no effect on lipid content of samples.

Microalgae as a source of saturated and unsaturated fatty acids, pigments, pharmaceutical and food metabolites, has received more focus by biological researchers at last decades. The amount and composition of fatty acids produced by microalgae depended on biomass production and environmental factors such as changes in salinity, light and nutrient availability. In this study, the green microalgae Dunaliella bardawil isolated from Chabahar Bay was cultured under different salinities (35, 70 and 105 g/L) using Conway medium. All treatments with air pump at 25±2 ° C and 12L: 12D (h) photoperiod and aerated. Effect of different salinity on the growth rate, lipid production and fatty acid composition of algal biomass were examined. ANOVA results showed that the highest growth rate and lipid content in the salinity of 70 g/L was obtained which are 933 and 206 milligrams per liter, respectively. Maximum and minimum lipid content of D. bardawil measured, 24.5 and 19 percent, at 105 and 35 ppt, respectively. Due to reduced cell density in 105 grams of salt per liter of fat produced per unit volume decreased to 65mg/L. The results show that D. bardawil purification from Chabahar Bay with degree unsaturation between 95-73 has great potential for biodiesel production.