Unsaturated Fatty Acid Content Research Articles

Multivariate modelling analysis for prediction of glycidyl esters and 3-monochloropropane-1,2-diol (3-MCPD) formation in periodically heated palm oil

Palm oil is a vegetable oil that is widely used for cooking and deep-frying because of its affordability. However, repeatedly heated palm oil is also prone to oxidation due to its significant content of unsaturated fatty acids and other chemical toxicants such as glycidyl esters and 3-monochloropropane-1,2-diol (3-MCPD). Initially, the physicochemical properties such as colour, viscosity, peroxide, p-anisidine and total oxidation (TOTOX) of periodically heated palm oil were investigated. Chemical profiling and fingerprinting of six different brands of palm cooking oil during heating cycles between 90 and 360 min were conducted using Fourier transform infrared (FTIR) and 1H Nuclear Magnetic Resonance (NMR) metabolomics. In addition, the multivariate analysis was employed to evaluate the 1H NMR spectroscopic pattern of repeatedly heated palm oil with the corresponding physicochemical properties. The FTIR metabolomics showed significant different of the chemical fingerprinting subjected to heating duration, which in agreement with the result of 1H NMR metabolomics. Partial least squares (PLS) model revealed that most of the physicochemical properties of periodically heated palm oil are positively correlated (R2 values of 0.98–0.99) to their spectroscopic pattern. Based on the findings, the color of the oils darkened with increased heating time. The peroxide value (PV), p-anisidine value (p-AnV), and total oxidation (TOTOX) values increased significantly due to degradation of unsaturated compounds and oxidation products formed. We identified targeted metabolites (probable carcinogens) such as 3-monochloropropane-1,2-diol (3-MCPD) and glycidyl ester (GE), indicating the conversion of 3-MCPD to GE in repeatedly heated oils based on PCA and OPLSDA models. Our correlation analysis of NMR and physicochemical properties has shown that the conversion of 3-MCPD to GE was significantly increased from 180 to 360 min cooking time. The combination spectroscopic techniques with physicochemical properties are a reliable and robust methods to evaluate the characteristics, stability and chemical's structure changes of periodically heated palm oil, which may contribute to probable carcinogens development. This study has proven that combination of NMR and physicochemical analysis may predict the formation of the probable carcinogens of heated cooking oil over time which emphasizing the need to avoid certain heating cycles to mitigate formation of probable carcinogens during cooking process.

Optimizing Artemia Enrichment: A Low DHA/High EPA Protocol for Enhanced n-3 LC-HUFA Levels to Support Greater Amberjack (Seriola dumerili) Larval Rearing.

Most commercial products available for Artemia sp. enrichment include high levels of docosahexaenoic acid (DHA) to boost its nutritional value, though with limited success. In this regard, the present study evaluated the alternative utilization of eicosapentaenoic acid (20 : 5n-3; EPA) oils to improve the n-3 long-chain highly unsaturated fatty acid content (n-3 LC-HUFA) in enriched Artemia sp. to feed greater amberjack (Seriola dumerili) larvae. Five experimental emulsions containing increasing levels of EPA from 0.8% to 60% of total fatty acids (TFA) and n-3 LC-HUFA (1.3%-70.6% TFA) were formulated. Each diet was fed to greater amberjack larvae (17-35 days posthatch (dph)) in three replicate 200-L tanks. The dietary EPA supplementation significantly improved larval growth during the feeding trial and survival at 35 dph (P < 0.05). In addition, larval fatty acid profiles showed a positive correlation with dietary EPA. Finally, despite the sum of total skeletal anomalies and column anomalies were not significantly affected by dietary EPA, increasing dietary EPA, and n-3 LC-HUFA tended to reduce the incidence of these types of anomalies in greater amberjack larvae at 35 dph. Based on these results, S. dumerili larvae could be successfully grown with low DHA but high EPA-rich oil enrichment products when n-3 LC-HUFA content in Artemia sp. is maintained in sufficient amounts.

Determination of the Optimal Conditions for the Mass Culture of Large-Type Rotifers (Brachionus plicatilis) at Low Temperatures

We aimed to determine the optimal conditions for the mass culture of rotifers, which can be used as feed for cold-water fish species at low temperatures. The growth and specific growth rates (SGRs) of rotifers were assessed considering water temperature, salinity, density, dissolved oxygen (DO) levels, and the amount of Chlorella supplied as feed. The growth of rotifers was higher at 15 °C than at 10 °C and at salinities of ~11–17 psu. Initial inoculation densities of 500 and 700 individuals/mL resulted in the highest rotifer density, and SGR was highest at 100 individuals/mL. DO concentration did not significantly affect the growth and SGRs of rotifers. Enrichment with fatty acids is important to supplement the diet of cold-water fish species. Highly unsaturated fatty acid content increased with enrichment time to 14.04 ± 0.86% at 12 h and 15.58 ± 2.20% at 24 h. Thus, the optimal conditions for rotifer mass culture are a water temperature of 15 °C, salinity of 11–17 psu, initial inoculation density of 300–500 individuals/mL, DO concentration of 8 mg/L or more, and Chlorella supply at 7.5 × 1012 cells/mL. Therefore, the present study suggests optimal culture conditions of rotifers at low temperatures for breeding cold-water fish species.

Determination of nutritional signatures of vegetable snacks formulated with quinoa, amaranth, or wheat flour

Consumers demand food products that can impact positively health. Those made from quinoa or amaranth flours could meet these expectations. Thus, the main goal of this work was to evaluate the nutritional composition of easy-to-eat snacks combining red pepper, carrot, or zucchini with quinoa or amaranth flours, well-recognized superfoods. In addition, these were compared with snacks incorporating wheat flour, a widely used conventional cereal. The results showed higher protein content in quinoa or amaranth snacks. The snacks with quinoa showed lower saturated fatty acid contents and the highest contents of unsaturated fatty acids. Furthermore, the discriminant model obtained could be used as a powerful predictive model to classify the samples according to the vegetable and flours used. Besides, the canonical discriminant analysis showed that the most influential grouping variable was the flour rather than the vegetable.

Effects of Different Dietary Energy Levels on Development, Quality of Carcass and Meat, and Fatty Acid Profile in Male Lambs.

This experiment was conducted to study the effects of dietary energy level on the growth performance and meat quality of weaned Alpine Merino lambs. The study ran for a total of 104 days (20-day pretrial, 84-day trial). From three groups of test lambs, we randomly selected ten lambs per group to determine slaughter performance, meat quality characteristics, and organ indexes. The slaughter performances of the lambs improved as the dietary energy level increased. The live weight before the slaughter of the lambs was significantly higher in the high group than in the low and medium groups. The carcass weight was significantly higher in the high group than in the low group. Dietary energy level had little effect on the organ weight of lambs. Meat quality differed among the three dietary energy levels. The muscle yellowness and redness scores decreased significantly as the energy levels increased. The C18:0, C21:0, C20:1, C18:2n6c, and C20:2 contents in the muscle were significantly higher in the high group than in the medium and low groups. The C18:3n6 content in the muscle was significantly higher in the low group than in the medium group. The C20:5n3 content in the longissimus dorsi was significantly higher in the high group than in the medium and low groups. The monounsaturated and unsaturated fatty acid contents in the muscle were significantly higher in the high group than in the low group. A dietary energy level of 10.5 MJ/kg is suitable for fattening weaned male Alpine Merino lambs.

Effects of Extraction Strategies on Yield, Physicochemical and Antioxidant Properties of Pumpkin Seed Oil.

This study investigated the effects of three extraction methods, including cold pressing (CP), microwave pretreatment pressing (MP), and supercritical fluid extraction (SFE), on the yield, physicochemical properties, bioactive compounds content, and antioxidant properties of pumpkin seed oil (PSO). Furthermore, the correlation between bioactive compounds and the antioxidant properties of PSO was determined. The results revealed that the yield of PSO extracted using the three methods was in the order of SFE > MP > CP. Additionally, the PSO generated by SFE showed the highest unsaturated fatty acid content, followed by MP and CP. Additionally, MP-PSO exhibited the highest acid value and saponification value, while SFE-PSO displayed the highest moisture content, peroxide value, and iodine value. Moreover, the PSO generated by MP demonstrated superior antioxidant properties compared to that of PSOs from CP and SFE in the oxidation induction, DPPH, FRAP, and ABTS tests. Finally, the correlation analysis revealed that specific types of bioactive compounds, such as β-sitosterol and γ-tocopherol, were highly correlated with the antioxidant properties of PSOs. Consequently, this study provides comprehensive knowledge regarding PSO extraction, physicochemical properties, bioactive compound extraction, and the correlated antioxidant properties.

Changes in seed yield and oil quality of flax (Linum usitatissimum L.) for industrial use in response to nitrogen and potassium fertilization

ABSTRACT The effect of nitrogen (N) and potassium (K) fertilization on yield and oil content in flaxseed, chemical properties and the composition of the fatty acids in the seed oil of flax, is important considering the growing global demand of the oil. The experiment was conducted at Barrackpore, West Bengal, India, with a combination of four N (0, 40, 80 and 120 kg ha−1) and three K (0, 30 and 60 kg ha−1) doses replicated thrice in a randomised complete block design. The quality of flax seed oil was significantly influenced by N and K fertilization. Higher N doses decreased the seed oil content but increased the oil yield. Increased N doses reduced the iodine value (IV), peroxide value (PV), and unsaturated fatty acid (UFA) content, particularly the α-linolenic acid (ALA) content in flax seed oil while the acid value (AV), free fatty acid (FFA), saturated fatty acid (SFA) and oleic acid contents were increased with N application. Potassium fertilization decreased the values of FFA, PV, ALA in flax seed oil and enhanced the oleic acid and poly-unsaturated fatty acid (PUFA) content. The UFA/SFA and oleic acid/ALA ratio decreased at higher N and K doses.

Effect of Zinc Excess on Some Physiological Parameters and on the Fatty Acids Profile of Sinapis alba L. and Brassica juncea L. (Czern)

Zinc (Zn) is a vital micronutrient for all living organisms, but in high concentrations, it is a major anthropogenic pollutant. In this study, it was investigated the effect of zinc excess concentrations (50, 100, and 150 mg kg−1) in the substrate on some physiological parameters and the dynamics of fatty acid (FA) content in yellow mustard (Sinapis alba L. cv. Belgia) and oriental mustard (Brassica juncea L. (Czern) cv. Slavanka). The Zn concentration of 50 mg kg−1 did not affect the physiological parameters of yellow mustard, whereas some physiological parameters slightly decreased in oriental mustard. Moreover, this concentration stimulated an increase in total and unsaturated FAs content in leaves of both species, along with high Zn accumulation by both species. The Zn concentrations of 100 and 150 mg kg−1 in substrate had a negative effect on the state of plants as measured by the studied physiological parameters and caused different changes in FAs content in yellow and oriental mustard. Particularly, the total amount of FA increased in comparison to the control, but this increase was due to an elevation in saturated FA (SFA) content. At the same time, the total FA content in oriental mustard slightly decreased while the proportion of unsaturated FAs to SFA kept rising. According to the present data and analysis of the available literature, two strategies of adaptation to heavy metals were suggested through the changes in FAs: height-resistant horticultural plant species on the one side and sensitive species on the other.

Content of fatty acids in lipids of adipose derived mesenchymal stem cells

The content of fatty acids in the lipids of mesenchymal stem cells of dog adipose tissue culture was studied. Mesenchymal stem cells of dog adipose tissue culture were obtained by culturing the primary material in a CO2 incubator with a content of 5 % CO2, at a temperature of 37 °C in DMEM medium with the addition of 10–15 % fetal bovine serum and 1 % antibiotic-antimycotic. When the confluency of the monolayer reached 70–80 %, the cells were transferred to a suspension and subcultivated in order to reduce the heterogeneity of the culture and obtain a sufficient amount of biological material. The lipids of the obtained stem cells were analyzed for the content of fatty acids by the method of thin-layer gas-liquid chromatography. Determination of the content of lipids of fatty acids in FSK of a cat was carried out by the Folch method. A mixture of fatty acid methyl esters was analyzed on a Trace GC Ultra gas chromatograph with a flame ionization detector on a capillary column SPTM –2560, 100 m x 0.25 mm ID, 0.20 μm film (Supelco). Identification of fatty acids was carried out using a standard sample of Supelco 37 Сomponent FAME Mix. Quantitative assessment of the LC spectrum was carried out by the method of normalization of the peak planes of methylated LC derivatives and their content was determined as a percentage of the total content of all LC. The conducted study of the content of fatty acids in lipids made it possible to reveal certain features of the lipid metabolism of mesenchymal stem cells cultured in dog adipose tissue. A high content of oleic acid, characteristic of cells resistant to apoptosis and with high proliferative potential, was determined; a high ratio of unsaturated linoleic to saturated stearic acid (С18:1/С18.0), which reflects the high activity of the stearoyl-coenzyme-desaturase enzyme and, indirectly, the active state of the Wnt/β-catenin signaling pathway; inability to lengthen the chain of saturated fatty acids; lack or low activity of de novo synthesis of omega-6 polyunsaturated fatty acids. 18 fatty acids were found in the composition of lipids of fetal stem cells of a cat, of the saturated ones - the most palmitic acid (33.70 ± 0.02 %), of the monounsaturated ones – oleic acid (21.63 ± 0.03 %), of the polyunsaturated ones – linoleic acid (6.45 ± 0.07 %). The least amount of cis-,11,14-eicosadienoic acid (0.04 ± 0.01 %) was found in the composition of cell lipids. The total amount of saturated fatty acids in dog mesenchymal stem cell lipids was 65.65 ± 0.02 %), unsaturated fatty acids – 34.35 ± 0.02 %. Monoene fatty acids were determined in the amount of 24.46 ± 0.02 %, and polyene – 9.89 ± 0.02 %. The ratio index of polyunsaturated fatty acids ω 3 to ω 6 is 0.40. Lipids of mesenchymal stem cells of adipose tissue culture were characterized by a lower content of monoene unsaturated fatty acids 24.46 ± 0.02; (P &lt; 0.05), with a higher content of ω3 fatty acids 3.04 ± 0.02 %; (P &lt; 0.05), with a lower content of ω6 fatty acids 6.86 ± 0.02 %; (P &lt; 0.05) in contrast to lipids of red bone marrow stem cells.

Postpartum Body Condition Score (BCS) and Lactation Stage (30 and 60 Days) Affecting Essential Fatty Acids (EFA) and Milk Quality of Najdi Sheep.

Body condition scoring (BCS) can be used to assess the energy reserves of sheep during feeding, production, and weaning. The aim of this study was to evaluate the influence of BCS after parturition in stages of lactation (30 and 60 days) on the milk quality of Najdi ewes. The ewes were milked in the morning after their lambs had been isolated. Milk composition and fatty acid profiles (FA) were analyzed at 30 and 60 days of lactation after assessment of the sheep's body condition. The sheep were classified into the following body conditions: 2.5, 3.0, 3.5, and 4.0. Sheep milk contained significant (p < 0.05) levels of protein at a BCS of 3.5 and on day 60 of lactation. The ewes with a BCS of 2.5 had a high milk content (p < 0.05) of unsaturated fatty acids (USFA), monounsaturated fatty acid (MUFA), oleic acid (OA), vaccenic acid (VA), and LA at day 60 of lactation. This result shows that the ewes with a BCS of 2.5 were able to produce high-quality milk, and 60 days of lactation was the preferred time for producing good milk and tasty and healthy dairy products.

MaC2H2-like regulates chilling stress response of 'Fenjiao' banana by modulating flavonoid synthesis and fatty acid desaturation.

Chilling injury (CI) is a major problem that affects fruit quality and ripening. Herein, chilling stress severely inhibited the expression of transcription factor MaC2H2-like. MaC2H2-like activates the expression of genes associated with flavonoid synthesis (MaC4H-like1, Ma4CL-like1, MaFLS, and MaFLS3) and fatty acid desaturation (MaFAD6-2 and MaFAD6-3), the leading indicators of chilling tolerance. MaC2H2-like interacts with MaEBF1 and boosts the transcriptional activity of MaFAD6-2, MaFAD6-3, Ma4CL-like1, and MaFLS. The overexpression of MaC2H2-like reduced fruit CI, induced the expression of these genes and increased the content of flavonoid and unsaturated fatty acid. Meanwhile, the silencing of MaC2H2-like increased fruit CI and downregulated the expression of those genes and reduced the content of flavonoid and unsaturated fatty acid. These results indicate that MaC2H2-like function as new player in modulating fruit CI by regulating flavonoid synthesis and fatty acid desaturation. MaC2H2-like could be a useful candidate gene for improving cold tolerance in 'Fenjiao' banana.

Conching process time, sauco by-product concentration, and sacha inchi oil levels identification for the enrichment of dark chocolate

Chocolate is a widely consumed product with high levels of polyphenols; unfortunately, it is reduced during the process. Adding other components allows for counteracting the polyphenols lost during chocolate processing and reducing the content of unsaturated fatty acids, affecting its physical properties. This study identified the conching time, concentration of sauco by-products, and levels of sacha inchi oil to produce enriched dark chocolates. For this study, sauco by-products in percentages of 2, 6 and 10%, sacha inchi oil in levels of 1, 3, and 5%, and three conching times of 16, 20, and 24 h were added to 75% dark chocolates, and the process conditions were optimized through the response surface methodology (RSM). The physicochemical properties of the dark chocolates were studied, observing that the sauco by-product, sacha inchi oil, and conching time significantly affected (p < 0.05) the variables of antioxidant activity, total phenol content, rheology, hardness, and particle size. The R2 correlation of the factors declared against the variables indicated the model's reliability as it was close to 1. The results suggest that incorporating sauco by-products allows for obtaining chocolates with good chemical properties; however, high percentages of sacha inchi oil and shorter conching time cause a negative effect on the chocolate affecting the physical properties.

Associations of Fatty Acid Profile with Abdominal Obesity in Men.

The content of individual unsaturated fatty acids in blood plasma (measured by HPLC) and their association with abdominal obesity in a group of men (mean age 52.2 years) was analyzed. The abdominal obesity was diagnosed according to the criteria of the All-Russian Scientific Society of Cardiology (waist circumference >94 cm). Men with abdominal obesity had higher levels of ω-6 γ-linolenic and dihomo-γ-linolenic acids, as well as ω-3 eicosapentaenoic and docosahexaenoic acids. They also had significantly elevated plasma levels of triglycerides and glucose and lower levels of HDL. Using single-factor ROC analysis we determined optimal cut-off thresholds for fatty acid levels indicating the presence of abdominal obesity. The results of regression analysis showed that the level of γ-linolenic acid is directly associated with the chance of abdominal obesity.s.

Identification of Fat in Pork Using Fourier Transform Infrared Spectrum and GC-MS

Halal food safety issues receive serious attention. Methods for analyzing contamination of non-halal ingredients, such as lard, must be developed to assist in the halal authentication process for food. This study was conducted to compare the fat profile of pork thighs using FT-IR and GC-MS. The pork is dried in the oven and then extracted using n-hexane. The resulting fat was characterized by FT-IR. Determination of fatty acids was carried out by GC-MS using a derivatization technique. Based on the results of the study showed that the infrared pattern of lard can be identified from the difference in absorption intensity. Pork fat has a higher unsaturated fatty acid content than beef and chicken. Infrared spectra can confirm the presence of -C=C- bonds at 3005, 1745, 1116, 1550, and 722 cm-1. The FTIR data shows that there are larger unsaturated fatty acid groups in pork fat than in beef and chicken fat. This procedure is a non-destructive method that can be carried out quickly, and cheaply, and can be developed into a routine procedure for halal authentication of food. Based on the results of unsaturated fatty acid testing with GC-MS it can show the content of oleic acid (C18:1) contained in pork. The results of mapping the content of free fatty acids in pork can be used to complete halal authentication data easily and quickly.

Oxidative stability of emulsions made with self-extracted oil from euryhaline microalgae Spirulina and Scenedesmus

The fatty acid compositions and tocochromanol concentrations (α-, γ + β-, δ-tocopherol and δ-tocotrienol) of oil extracted from euryhaline microalgal strains (Spirulina subsalsa (Spi A), Scenedesmus MKB (Scnd) and Spirulina sp. (Spi B)) were analyzed. The oxidative stability of microalgae-based oil-in-water emulsions at pH 7 was also determined by measuring lipid hydroperoxide and headspace hexanal formation. The content of saturated fatty acids was highest in Spi B oil whereas n-3 linolenic and eicosapentaenoic acids were high in Spi A. No significant difference was reported in the total tocochromanol homolog contents of Spi A and Scnd oils, but it was significantly higher in Spi B oil. Tocochromanol depletion analysis revealed that δ-tocopherol and δ-tocotrienol had a slower depletion rate than other homologs and that their high content prolonged the hexanal lag phase of Spi B oil-in-water emulsions up to 21 days. The fact that Spi B had the lowest unsaturated fatty acid content and the highest tocochromanol concentration resulted in greater oxidative stability. Spi A oxidized faster than Scnd irrespective of their similar tocochromanol content which might be due to the higher amounts of unstable 18:3 and 20:5 fatty acids. These data suggest that these microalgal oils could have applications in sustainable food systems.

Increasing the oxidative stability of linseed oil

The object of the research is the process of oxidation of linseed oil at elevated temperature. Linseed oil is a valuable raw material for the chemical, food, cosmetic and other industries. The use of linseed oil is complicated by intensive oxidation processes associated with a high content of unsaturated fatty acids. Therefore, an important task is to develop and improve methods of oxidative stabilization of linseed oil. The oxidation process of unrefined linseed oil (CAS Number 8001-26-1) at a temperature of 110 °C in its original form and with the addition of antioxidants was studied. The effect of antioxidant concentrations (tocopherol, butylhydroxyanisole and butylhydroxytoluene) in the mixture on the induction period of linseed oil was found. The induction period was determined by differential scanning calorimetry. The total concentration of the mixture of antioxidants in each experiment was 0.02 %. The induction period of the initial oil was 155.31 min. Rational ratios of antioxidants in the mixture were found: tocopherol: butylhydroxyanisole (50:50) %; tocopherol: butylhydroxytoluene (50:50) %; tocopherol: butylhydroxyanisole: butylhydroxytoluene (33.33:33.33:33.33) %. At the same time, the oil induction periods are 295.7 min., 290.1 min. and 290.2 min., respectively. The quality indicators of the initial linseed oil and with the addition of the determined rational ratios of antioxidants after 2 hours of aging at a temperature of 110 °C were determined. The peroxide values of the samples were 8.5, 3.2, 3.6, 3.7 ½ O mmol/kg, respectively. The research results make it possible to introduce antioxidants in the production of linseed oil in rational concentrations. This will help increase the production of linseed oil resistant to oxidation at elevated temperatures, which will provide various industries with high-quality raw materials

Characterization of Agronomic and Seed Oil Features for Different Cultivars of Tree Peony.

Tree peony is a unique oil plant resource in China, and tree peony seed oil is one of the healthy edible oils with a very promising future. However, the main oil tree peony cultivars promoted in China are Paeonia ostii 'Fengdan' and Paeonia rockii. In order to explore new oil tree peony cultivars, 68 tree peony cultivars were investigated and cultivars with oil potential were selected by cluster analysis and grey relational analysis (GRA) in this study. The results demonstrated that the 68 cultivars varied significantly in terms of agronomic characteristics (p < 0.05), with the coefficient of variation in seed yield per plant reaching a high of 75.36%. The oil content of 46 cultivars was higher than 'Fengdan' (20.87 ± 0.26%) and 'Zibanbai' (21.24 ± 1.01%), while the alpha-linolenic acids and total unsaturated fatty acid contents of 26 cultivars were higher than 'Fengdan' (39.79 ± 1.13% and 88.99 ± 0.47%) and 'Zibanbai' (40.51 ± 0.09% and 93.59 ± 0.09%). Finally, three cultivars with better integrated traits were selected by cluster analysis and grey relational analysis (GRA), comprising of 'Changshoule', 'Xianchizhenghui', and 'Yupantuojin'. The contents of alpha-linolenic acids and total unsaturated fatty acids in 'Changshoule' (47.98 ± 0.17% and 93.60 ± 0.08%), 'Xianchizhenghui' (49.44 ± 0.63% and 93.80 ± 0.06%), and 'Yupantuojin' (40.46 ± 0.26% and 93.58 ± 0.06%) were higher than that of 'Fengdan' (39.79 ± 1.13% and 88.99 ± 0.47%). In general, these cultivars can be used as hybrid parental materials for breeding new excellent oil tree peony cultivars.

The metabolism of membrane lipid participates in the occurrence of chilling injury in cold-stored banana fruit

Banana fruit is highly vulnerable to chilling injury (CI) during cold storage, which results in quality deterioration and commodity reduction. The purpose of this study was to investigate the membrane lipid metabolism mechanism underlying low temperature-induced CI in banana fruit. Chilling temperature significantly induced CI symptoms in banana fruit, compared to control temperature (22 °C). Using physiological experiments and transcriptomic analyses, we found that chilling temperature (7 °C) increased CI index, malondialdehyde content, and cell membrane permeability. Additionally, chilling temperature upregulated the genes encoding membrane lipid-degrading enzymes, such as lipoxygenase (LOX), phospholipase D (PLD), phospholipase C (PLC), phospholipase A (PLA), and lipase, but downregulated the genes encoding fatty acid desaturase (FAD). Moreover, chilling temperature raised the activities of LOX, PLD, PLC, PLA, and lipase, inhibited FAD activity, lowered contents of unsaturated fatty acids (USFAs) (γ-linolenic acid and linoleic acid), phosphatidylcholine, and phosphatidylinositol, but retained higher contents of saturated fatty acids (SFAs) (stearic acid and palmitic acid), free fatty acids, phosphatidic acid, lysophosphatidic acid, diacylglycerol, a lower USFAs index, and a lower ratio of USFAs to SFAs. Together, these results revealed that chilling temperature-induced chilling injury of bananas were caused by membrane integrity damage and were associated with the enzymatic and genetic manipulation of membrane lipid metabolism. These activities promoted the degradation of membrane phospholipids and USFAs in fresh bananas during cold storage.

Effect of Vacuum Roasting on Total Selenium Content of Selenium-Enriched Rapeseed, Maillard Reaction Products, Oxidative Stability and Physicochemical Properties of Selenium-Enriched Rapeseed Oil.

Selenium-enriched rapeseed (SER) is an emerging oil seed. Roasting is beneficial in improving oil yield and promoting the release of micronutrients into SER oil, but high temperatures and dry air lead to selenium loss and fatty acid degradation in SER. To minimize the selenium loss and improve the SER oil quality, this study investigated the effects of vacuum (VC) roasting (90-170 °C for 30 min) on the SER selenium content, Maillard reaction products, oxidative stability, and physicochemical properties of SER oil, with conventional dry air (DA) roasting as the control. The results showed that the selenium loss in VC-roasted SER meals increased from 7.17 to 19.76% (90-170 °C for 30 min), which was 47.13 to 80.48% of that in DA-roasted SER meals, while no selenium was detected in the SER oils. Compared to DA roasting, VC roasting (90-170 °C for 30 min) reduced lipid oxidation products (LOPs), Maillard reaction products (MRPs), and benzo[a]pyrene contents, and increased carotenoids, unsaturated fatty acid contents, reaching a maximum oil yield of 35.58% at a lower temperature (130 °C for 30 min). Selenium contents exhibited a highly significant negative correlation with MRPs and LOPs (p ≤ 0.005). The VC roasting retarded selenium loss and improved SER oil quality compared to conventional DA roasting.

Comparative Study on the Oil Content and Fatty Acids Profile among Some Brassica rapa L. Genotypes

The study was carried out at Biochemistry, Agricultural Chemistry and Environmental Science laboratory of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh from March, 2020 to September, 2021 to estimate oil content and fatty acids composition of some Brassica rapa L. genotypes. The experiment was laid out in a completely randomized design with three replications and consisted of four genotypes viz., BARI Sarisha-14, Brown Special, Yellow Special, Tori-7 and their F1s. Result revealed that the oil content ranged from 34.25-45.05% among the studied genotypes. The parent, Yellow Special contained the highest amount of oil (45.05%) and Brown Special contained the lowest amount (39.48%), while among the F1s, (Brown Special×Yellow Special) contained the highest amount (39.04%) and (BARI Sar-14×Brown Special) contained the lowest amount (34.25%). The major saturated and unsaturated fatty acids content ranged from 3.92-5.42% and 92.39-93.50% respectively. The parent, Brown Special and the F1- (BARI Sar-14×Brown Special) contained the highest amount of unsaturated fatty acids (92.81%) and (93.50%) respectively, while the parent Yellow Special and the F1- (Brown Special×Tori-7) contained the lowest amount of saturated fatty acids (3.96%) and (3.92%) respectively. The highest poly unsaturated fatty acids containing parent was Tori-7 (16.98%) and F1 was Yellow Special×Tori-7 (19.27%). The erucic acid content ranged from 44.97- 54.56%. Among the parents, Tori-7 and among the F1s-Yellow Special×Tori-7 contained the lowest amount of erucic acid (44.97%) and (45.37%) respectively. Therefore, the parents and F1s with high level of poly unsaturated fatty acids and low level of erucic acid could be selected for further development of these trait.