Fatty Acid Profile Composition Research Articles

Fatty acid composition and lipid profiles as chemotaxonomic markers of phytopathogenic fungi Puccinia malvacearum and P. glechomatis

The analysis of the overall fatty acid pattern as well as their distribution in various lipid classes of phytopathogenic fungi Puccinia malvacearum and P. glechomatis are considered as chemotaxonomic biomarkers. Puccinia malvacearum on Alcea rosea and P. glechomatis on Glechoma hederacea collected from plants grown in various localities were analysed to determine their fatty acid composition. Both species synthesised significant amounts of saturated palmitic and stearic acids as well as 9,10-epoxy-octadecanoic acid, which rarely occurs in the nature. Both species synthesised hydroxy FAs including 9,10-dihydroxy octadecanoic acid and long-chain 2-hydroxy fatty acids.2-hydroxy 18:0 and 3-hydroxy 20:0 fatty acids were present only in P. malvacearum spores, and these may be the chemotaxonomic markers of the species. Ultra-high performance liquid chromatography mass spectrometry was performed for a comparative lipidomic analysis of P. malvacearum and P. glechomatis. The results revealed the complexity of molecular lipid species of these fungi. P. malvacearum and P. glechomatis lipids were characterised by the presence of a high number of triglyceride (TG) species. 9,10-epoxy octadecanoic fatty acid was found in TGs. Among the many types of oxidised TGs identified in P. glechomatis lipids, the most abundant species corresponds to TG(22:5+6O_17:0_18:2). P. malvacearum and P. glechomatis produced various ceramide species with different FAs from 14 to 24 chain-length. Unusual lipids like (O-acyl)-ω-hydroxy FA 18:0/18:0 in P. glechomatis and (O-acyl)-ω-hydroxy FA 18:0/20:0 and 18:0/22:0 in P. malvacearum were detected. The analysis of the polar lipid composition showed the presence of phosphatidylcholine and phosphatidylethanolamine as the main phospholipid classes of Puccinia spp. with the highest diversity of molecular species. Other phospholipids phosphatidic acid, phosphatidylglycerol phosphatidylserine and phosphatidylinositol were present in smaller amounts.The diversity of the neutral and polar lipid composition and fatty acid profile of P. malvacearum and P. glechomatis can be used in chemotaxonomic studies.

Virgin Olive Oil Phenols, Fatty Acid Composition and Sensory Profile: Can Cultivar Overpower Environmental and Ripening Effect?

The authenticity and typicity of monocultivar oils and knowledge of the changes that environmental olive growing conditions bring to naturally present antioxidants and sensory attributes of virgin olive oils (VOO) are important for quality and safety improvement. This study delivers a comprehensive evaluation of the factors affecting phenolics, fatty acid composition and sensory characteristics of cultivars Oblica and Leccino VOOs throughout ripening season at two distinct olive growing environments during three consecutive crop years, and ranks the importance of each factor. Specified parameters were significantly influenced by olive growing environmental conditions. At the colder location of higher altitude, both cultivars gained higher amount of stearic, linoleic and linolenic fatty acids, as well as a higher proportion of phenolic compounds, but lower amounts of oleic fatty acid. At the warmer location of lower altitude, both cultivars had oils with lower level of fruitiness, bitterness and pungency. Analysis of the main components showed that VOOs were primarily differentiated by the cultivar, then main groups were divided with regard to the growing site, while harvest period affected the biosynthesis of natural VOOs antioxidants but had the least impact. These results reveal that the composition of fatty acids, phenolic content and sensory profile are predominantly characteristics of a cultivar.

Extraction, fatty acid profile, phytochemical composition and antioxidant activities of fixed oils from spices belonging to Apiaceae and Lamiaceae family.

The online version contains supplementary material available at 10.1007/s13197-021-05036-1.

Lipid profile by direct infusion ESI-MS and fatty acid composition by GC-FID in human milk: Association with nutritional status of donors

Nutritional status of donors of human milk (HM) to a human milk bank was investigated as a factor capable of modulating lipid concentrations of this food. Colostrum and transitional milk from 55 women with different body mass indexes (eutrophic, overweight and obese) were collected and separated into pools to evaluate the fatty acid composition and triacylglycerols lipid profile. Gas chromatograph with flame ionization detector (GC-FID) and electrospray ionization mass spectrometer (ESI-MS) were applied in these pools. Transitional milk pool from overweight donors showed the highest percentages of caprylic acid, which were 2.39 %. The trans 10, cis 12 isomer stood out in the colostrum pool of donors with overweight with values of 0.31 %. Despite the α-linolenic precursor of the omega-3 family showing higher concentrations in the colostrum pool of obese donors, long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic (Epa) and docosahexaenoic (Dha) showed lower values in the obese donors colostrum and transitional pools, determined by GC-FID analysis. The concentrations of Epa and Dha in the colostrum pool of eutrophic donors were 0.42 % and 0.34 %, respectively, while in the colostrum pool of obese donors the values found for Epa (0.17 %) and Dha (0.26 %) were significantly lower. In the transitional milk pool of eutrophic donors, Epa concentrations were 0.31 % and Dha 0.32 %; already in the obese donors pool, Epa and Dha presented values of 0.08 % and 0.09 %, respectively, showing a significant difference (p<0.05). The spectra of lipid profiles identified by ESI-MS revealed that the Epa and Dha are probably transferred to HM triacylglycerol from obese donors, but in intensities less than 3%. Obesity may be associated with the composition of some important LC-PUFAs, a factor that can influence the lipid quality of HM.

Fatty Acid Composition and Volatile Profile of M. longissimus thoracis from Commercial Lambs Reared in Different Forage Systems.

Animal production factors can affect the fatty acid and volatile profile of lamb meat. The fatty acid and volatile composition of the M. longissimus thoracis was evaluated from 150 lambs from 10 groups of commercial lambs that differed in age, sex, diet and breed, from three farms, which represent typical forage lamb production systems in New Zealand. The meat from 4-month-old composite lambs slaughtered at weaning had a similar polyunsaturated to saturated fatty acid ratio compared to 6- to 8-month-old composite lambs, but a greater ratio than that of 12-month-old Merino lambs (p < 0.05), with all ratios being lower than the recommended ≥0.45. All lamb production systems produced meat with an omega-6 to omega-3 ratio below 1.5, well below the recommended ratio ≤ 4.0. Meat from 4-month-old lambs had higher C12:0, C14:0 and C16:0 and lower C18:0, reflecting the composition of the milk diet, resulting in higher atherogenic index than meat from other animal groups, while meat from 12-month-old Merino lambs, with lower content of polyunsaturated fatty acids, showed higher thrombogenic index. Meat from lambs processed at weaning contained the greatest concentration of eicosapentaenoic and docosahexaenoic acids, which would qualify as a ‘source’ or ‘good source’ of these target fatty acids based on the Commission of Regulation of the European Union or the Food Standards Australia New Zealand guidelines, respectively. Volatiles were extracted from the headspace of raw lean meat and 36 volatile compounds were identified. The abundance of carbon disulphide, isododecane, heptanal, 2,5-hexanediol and 3-octanone and pentanoic, octanoic, nonanoic and heptanoic acids was similar between all groups of lambs. Meat from 12-month-old Merino lambs had low abundance of acetic, propanoic, butanoic and hexanoic acids, and hexanal, octanal and dimethyl sulphide. For 6- to 8-month-old composite lambs, hexanal, octanal and nonanal were present at higher relative abundance in meat from lambs that grazed on chicory than perennial ryegrass. The significant differences in the fatty acid and volatile profiles in meat from 12-month-old Merino lambs compared with lambs slaughtered at weaning or further grazed on red clover, chicory or mixed pasture may result in distinctive nutritional value and lamb flavour.

Study of meat quality and flavour in different cuts of Duroc-Bamei binary hybrid pigs.

BackgroundMeat quality and flavour are important criteria for judging fresh pork and processed products. However, there have been few studies on meat quality and volatile flavour substances of different parts of binary hybrid pigs.ObjectiveTo study the differences in meat quality and volatile flavour substances between different cuts of pork, which could provide the basis for consumer decision‐making when purchasing pork.MethodsTwenty Du‐Ba binary hybrid pigs (first filial [F1] generation) bred from Duroc and Bamei pigs were used. This study systematically compared and analysed the basic nutritional components, amino acid composition, fatty acid composition and flavour profiles of longissimus dorsi, rib muscle and tendon meat of four Du‐Ba binary hybrid pigs; all assays were repeated in triplicate.ResultsCrude protein, calcium and phosphorus content in tendon meat were higher than that in the longissimus dorsi. The intramuscular fat content of the rib muscle was higher than that in the longissimus dorsi and tendon meat (p < 0.05). The amino acid content was highest in the tendon meat. The levels of essential amino acids and flavour‐associated amino acids per kilogram of longissimus dorsi were higher than those in the rib muscle and tendon meat. Moreover, the content of aspartic acid, serine and cystine were higher in the longissimus dorsi than in the other two parts. The type of saturated fatty acids and the type and content of unsaturated fatty acids in tendon meat were higher than in the longissimus dorsi and rib muscle. The total content of volatile flavour compounds was higher in the longissimus dorsi than in the rib muscle and tendon meat.ConclusionThe rib muscle contains high deposits of fat, and tendon meat has a relatively high nutritional value, while the longissimus dorsi has a stronger flavour.

Physicochemical Properties of Palm Oil‐Based Puff Pastry Model Margarines Related to Their Baking Performance in Long‐Term Storage

AbstractDeveloping trans‐free alternative fat solutions suitable for specific applications remains a challenge in edible fats and other domains. This is particularly true for palm oil‐based puff pastry margarines, which suffer from post crystallization problems, leading to dramatic loss of functionality. This research is aimed at investigating the influence of triacylglycerol (TAG) compositions of palm oil‐based puff pastry margarines on the physical properties of the fat crystal network, which determine the functionality of such products. Three model puff pastry margarines are produced at pilot scale under the same crystallization conditions. They share the same fatty acid composition and close solid fat content (SFC) profiles, whereas the proportions of major TAG (tripalmitoylglycerol (PPP), 1,3‐di‐palmitoyl‐2‐oleoylglycerol (POP), 1,2‐di‐palmitoyl‐3‐oleoylglycerol (PPO), 1,2‐dioleoyl‐3‐palmitoylglycerol (POO)) are different. Polymorphism, melting profile, hardness, microscopic structures, and baking performance (puffing effect) of the model fats are examined during a period of 6 months. The following results are obtained: 1) The TAG composition significantly influences the post crystallization processes occurring in palm oil‐based margarines. 2) High amounts of POP show negative influences. 3) The proportions of POP, PPO, and PPP should be carefully balanced to prevent detrimental crystal network rearrangements, leading to textural modifications (hardness increase) and significant reduction in baking performance.Practical Applications : The results presented in this work could be helpful for edible fat products developers, especially for roll‐in fat applications. This research provides an overview of the relevant properties to study for the assessment of puff pastry margarine functionality. It also highlights the importance of ensuring long‐term stability of palm oil‐based fat products. Finally, it emphasizes that certain combinations of fat materials should be avoided to maintain the quality of palm oil‐based puff pastry margarines.

Two Blends of Refined Rice Bran, Flaxseed, and Sesame Seed Oils Affect the Blood Lipid Profile of Chinese Adults with Borderline Hypercholesterolemia to a Similar Extent as Refined Olive Oil

Individual vegetable oils have a characteristic fatty acids (FA) composition and unique phytonutrient profiles, enabling formulation of oil blends that may have health-promoting effects. The primary objective of this study was to investigate effects of 2 oil blends made with refined rice bran, flaxseed, and sesame oils, with distinct monounsaturated to saturated FA, polyunsaturated to saturated FA, and omega-3 (n-3) to omega-6 FA ratios and different phytonutrient concentrations on blood lipid profile, compared with refined olive oil as a control. The secondary outcomes were other markers of cardiometabolic health. A parallel-design, randomized controlled trial compared consumption of 30g of allocated intervention oil per day for a period of 8 wk. The study recruited 143 borderline hypercholesterolemic (LDL cholesterol: 3.06-4.51mmol/L) Chinese volunteers between 50 and 70 y old and with a BMI (kg/m2) ≤27.5. All outcomes were measured every 2 wk, and the time × treatment interactions and the main effects of treatment and time were analyzed using an intention-to-treat approach. Compared with baseline (week 0), there were significant reductions during the post-intervention time points in serum total cholesterol (-3.47%; P<0.0001), LDL cholesterol (-4.16%; P<0.0001), triglycerides (-10.3%; P<0.0001), apoB (-3.93%; P<0.0001), total to HDL-cholesterol (-3.44%; P<0.0001) and apoB to apoA1 (-3.99%; P<0.0001) ratios, systolic and diastolic blood pressures (-3.32% and -3.16%, respectively; both P<0.0001), and serum glucose (-1.51%; P<0.05) and a small but significant increase in body weight (+0.7%; P<0.001) for all 3 intervention oils but no effects of intervention on HDL-cholesterol or apoA1 concentration. No significant effects of treatment or time × treatment interactions were found. Using blended vegetable oils that are extensively consumed in Asia, this study found that specific oil blends can improve blood lipid profile and other cardiometabolic parameters, to a similar extent as refined olive oil, in Chinese adults with borderline hypercholesterolemia. This trial is registered at www.clinicaltrials.gov as NCT03964857.

Bioconversion of volatile fatty acids into lipids by the oleaginous yeast Apiotrichum porosum DSM27194

Volatile fatty acids (VFA) derived from waste organics provide economical feedstocks for fuels and oleochemicals production. In this study, the valorization of VFA into microbial lipids by the oleaginous yeast Apiotrichum porosum DSM27194 was investigated. A. porosum DSM 27194 was able to assimilate different VFA mixtures containing acetic, propionic and butyric acid at different ratios for lipid production. By using a two-stage automated fed-batch fermentation strategy with glucose as initial carbon source and VFA mixtures as both carbon source and buffering agent, a dry cell mass concentration of 26.5 g/L with lipid content of 36.2% was achieved with the VFA ratio of 6:1:1 (acetic acid:propionic acid:butyric acid). Fatty acid composition profiles indicated that the lipid derived from VFA is better suited for biodiesel production compared to glucose as carbon source. Moreover, corn stover hydrolysate containing VFA was applied as raw feedstock. Excitingly, A. porosum DSM 27194 could consume all kinds of carbon source within the hydrolysate fast and simultaneously resulting in 28.0 g/L of dry cell mass containing 44.3% of lipid. This study provides a promising oleaginous yeast chassis of A. porosum DSM 27194 and an economical fermentation strategy of two-stage automated fed-batch fermentation for microbial lipid production from low-value VFA derived feedstocks.

Low-temperature effects on docosahexaenoic acid biosynthesis in Schizochytrium sp. TIO01 and its proposed underlying mechanism

BackgroundSchizochytrium species are known for their abundant production of docosahexaenoic acid (DHA). Low temperatures can promote the biosynthesis of polyunsaturated fatty acids (PUFAs) in many species. This study investigates low-temperature effects on DHA biosynthesis in Schizochytrium sp. TIO01 and its underlying mechanism.ResultsThe Schizochytrium fatty acid biosynthesis pathway was evaluated based on de novo genome assembly (contig N50 = 2.86 Mb) and iTRAQ-based protein identification. Our findings revealed that desaturases, involved in DHA synthesis via the fatty acid synthase (FAS) pathway, were completely absent. The polyketide synthase (PKS) pathway and the FAS pathway are, respectively, responsible for DHA and saturated fatty acid synthesis in Schizochytrium. Analysis of fatty acid composition profiles indicates that low temperature has a significant impact on the production of DHA in Schizochytrium, increasing the DHA content from 43 to 65% of total fatty acids. However, the expression levels of PKS pathway genes were not significantly regulated as the DHA content increased. Further, gene expression analysis showed that pathways related to the production of substrates (acetyl-CoA and NADPH) for fatty acid synthesis (the branched-chain amino acid degradation pathway and the pentose phosphate pathway) and genes related to saturated fatty acid biosynthesis (the FAS pathway genes and malic enzyme) were, respectively, upregulated and downregulated. These results indicate that low temperatures increase the DHA content by likely promoting the entry of relatively large amounts of substrates into the PKS pathway.ConclusionsIn this study, we provide genomic, proteomic, and transcriptomic evidence for the fatty acid synthesis pathway in Schizochytrium and propose a mechanism by which low temperatures promote the accumulation of DHA in Schizochytrium. The high-quality and nearly complete genome sequence of Schizochytrium provides a valuable reference for investigating the regulation of polyunsaturated fatty acid biosynthesis and the evolutionary characteristics of Thraustochytriidae species.

The effect of chemical refining process on the physicochemical and fatty acid composition of water melon seed oil (Citrulus lanatus L.)

A lot of watermelon seed waste is wasted, generally its only used to make “kuaci”, a kind of salted saline a snack made from watermelon seeds. As a member of Cucurbitaceae family, watermelon seeds can be used as a source of vegetable oil that predicted contains squalene inside like other Cucurbitaceae members. This study aims to determine the effect of refining process on the physicochemical properties and composition watermelon seed oil. Watermelon seed oil which is obtained by using Soxhlet extractor in n-hexane solvent was refined in 3 steps, which was degumming, neutralization, and bleaching, respectively. Degumming process used 3 concentrations of H3PO4, which were 0,15%; 0,20%; and 0,25%, respectively; whereas 3 zeolit concentrations of 2%; 4%; and 8%, respectively were used in bleaching steps. Data were analyzed by using 3x3 Factorial design and it was laid out with Randomized Completely Block Design, 3 replications and as the block is time analysis. The optimum yield of the watermelon (C. lanatus L.) seed oil is obtained in the amount of 48.47±0.91 % at 0.25% phosphoric acid concentration and 4% Zeolite concentration. The result of physicochemical analysis before and after the refining process have changed. The density, peroxide value and acid value show a significantly decrease, while only the saponification value shows an increase. Fatty acid composition (profile) of WSO before and after refining process does not change, comprises linoleic acid, palmitic acid, stearic acid and squalene (unsaturated hydrocarbon). Linoleic acid is the main compound of WSO (76.69%), followed by palmitic acid (14.60%), stearic acid (6.53%) and squalene (2.18%), respectively.

Exogenous l-proline improved Rhodosporidium toruloides lipid production on crude glycerol

BackgroundCrude glycerol as a promising feedstock for microbial lipid production contains several impurities that make it toxic stress inducer at high amount. Under stress conditions, microorganisms can accumulate l-proline as a safeguard. Herein, l-proline was assessed as an anti-stress agent in crude glycerol media.ResultsCrude glycerol was converted to microbial lipids by the oleaginous yeast Rhodosporidium toruloides CGMCC 2.1389 in a two-staged culture mode. The media was supplied with exogenous l-proline to improve lipid production efficiency in high crude glycerol stress. An optimal amount of 0.5 g/L l-proline increased lipid titer and lipid yield by 34% and 28%, respectively. The lipid titer of 12.2 g/L and lipid content of 64.5% with a highest lipid yield of 0.26 g/g were achieved with l-proline addition, which were far higher than those of the control, i.e., lipid titer of 9.1 g/L, lipid content of 58% and lipid yield of 0.21 g/g. Similarly, l-proline also improved cell growth and glycerol consumption. Moreover, fatty acid compositional profiles of the lipid products was found suitable as a potential feedstock for biodiesel production.ConclusionOur study suggested that exogenous l-proline improved cell growth and lipid production on crude glycerol by R. toruloides. The fact that higher lipid yield as well as glycerol consumption indicated that l-proline might act as a potential anti-stress agent for the oleaginous yeast strain.

Study on lipid production by reusing herb residues of Songling Xuemaikang Capsules

Songling Xuemaikang Capsules is a Chinese patent medicine mainly made of the Chineses medicine Puerariae Lobatae Radix and leaves of Pinus massoniana. During its production, a large amount of herb extraction residues would be treated as wastes, resulting in resource wasting and serious environmental pollution. In order to solve this problem, we took the hydrolysates of Puerariae Lobatae Radix, P. massoniana leaves, and whole herb residues of Songling Xuemaikang Capsules as the fermentation substrate to explore the ability of Rhodosporidium toruloides to produce microbial lipid. The results showed that the R. toruloides could produce lipid with use of the residues from Songling Xuemaikang Capsules, and the lipid contents reached 33.6%. The lipid products had similar fatty acid composition profiles to those of vegetable oils. Herb residues were converted into fermentation substrates in this study, and were recycled into the production of high value-added compounds to realize the transformation of the wastes, laying the foundation for the sustainable utilization of herb residues.

The effect of Pediococcus acidilactici J17 with high-antioxidant activity on antioxidant, α‑tocopherol, β‑carotene, fatty acids, and fermentation profiles of alfalfa silage ensiled at two different dry matter contents

The effects of inoculation of strain Pediococcus acidilactici J17 with high antioxidant activity and a widely used commercial inoculum of Lactobacillus plantarum MTD-1, on antioxidant status, concentrations of α‑tocopherol and β‑carotene, fatty acid composition and fermentation profiles of ensiled alfalfa prepared at two dry matter (DM) contents were investigated. Chopped fresh alfalfa was ensiled at two DM contents of approximately 300 (low DM) and 400 (high DM) g/kg fresh weight, and treated with distilled water (control), L. plantarumMTD-1 and P. acidilactici J17, respectively. Forages were ensiled in vacuum-sealed polyethylene bags containing 500 g wilted forage for 60 d, with 4 replicates for each treatment. All inoculants effectively improved fermentation profiles of silages and the silage with a high DM exhibited better effects on inhibiting proteolysis and lipid oxidation; however, the antioxidant strain P. acidilactici J17 had little influence on the fatty acid composition of alfalfa silage. Silages with a low DM had higher proportions of saturated fatty acid and monounsaturated fatty acid, and lower proportions of polyunsaturated fatty acid compared with the silages with a high DM. Extensive degradation of α-tocopherol and β-carotene in alfalfa occurred after ensiling. The concentration of α-tocopherol in control silage declined to almost half of its original concentration in fresh alfalfa. Concentrations of β-carotene in the control silages with the low and high DM were accounted for 1/3 and 1/2 of their original concentrations in fresh alfalfa, respectively. In comparison with control silage and silage treated with L. plantarum MTD-1, inoculation of P. acidilactici J17 with high-antioxidant activity markedly increased the total antioxidant capacity (T-AOC), catalase (CAT) activity and concentrations of α-tocopherol and β-carotene of alfalfa silage ensiled at both DM contents. On average, higher T-AOC was observed in silage with a high DM than silage with a low DM. However, both inoculants decreased superoxide dismutase (SOD) activity of ensiled alfalfa. These results indicated that the P. acidilactici J17 strain could be used as a candidate antioxidant inoculum to improve the antioxidant status of alfalfa silage.

Lipid profile and fatty acid composition of marine fish species from Northeast coast of Brazil.

Total lipid content, fatty acid composition and nutritional profile of lipid fraction of fourteen fish species from the Brazilian Northeastern coast were evaluated. Lipid content was determined by Bligh and Dyer methodology, whereas the fatty acid composition was determined by gas chromatography with flame ionization detector. The indices of atherogenicity, thrombogenicity and hypocholesterolemic/hypercholesterolemic ratio were used to evaluate the nutritional quality of lipid fraction. The total lipid content ranged from 0.25 to 3.09%, with higher values in L. synagris. A significant difference (p < 0.05) were noted in fatty acids composition between the fourteen fish species. PUFA were the major fatty acids in twelve of fourteen species and C. leiarchus showed the highest content. The n-3 content ranged from 69.83 to 270.62mgg-1 of total lipids, being EPA and DHA the major fatty acids in most of the species studied. The species L. synagris, M. bonaci and S. brasiliensis exceeded the WHO daily intake recommendation of 250mg per day from those fatty acids. The quality indexes of the lipid fraction as well as the n-6/n-3 and PUFA/SFA ratios indicated that all fish species can be healthy nutritional options, and can bring many benefits to human health. The principal component analysis resulted in a two-principal-component model that described 79.78% of data variance. Also, it highlighted that despite the differences between the breeding strategies of fish families, the species could be grouped according to their similarity in fatty acids composition.

Effect of Supplementation of Herd Diet with Olive Cake on the Composition Profile of Milk and on the Composition, Quality and Sensory Profile of Cheeses Made Therefrom.

Simple SummaryReplacing conventional feed with waste biomass produced by crop-industrial processes can be a good practice for the sustainability of crop-livestock systems and an interesting solution for their disposal—as long as they maintain the quality of products. Considering the relationship between feeding management and qualitative profile in products of animal origin, the aim of our study was to assess the effect of dietary olive cake supplementation on nutritional quality, fatty acid composition, volatile and sensory profile of milk and the cheese produced by dairy cows. The experiment was carried out on eighty-four healthy dairy Friesian cows, divided into two homogenous groups. Animals were fed with a conventional diet (CTR group) and a conventional diet supplemented with dried olive cake (OC group). Data showed that olive cake utilization in the diet of lactating dairy cows may modify the quality of dairy products. The increased unsaturated fatty acids (oleic acid, vaccenic acid and CLA) and decreased SFA (short- and medium-chain fatty acids) suggest a positive role of olive cake in improving the nutritional and nutraceutical properties of the cheese. Moreover, the olive cake affected not only the volatile profile of the cheese, but also its appearance, smell and taste, which are associated with a higher score of acceptance.Aim of the present study was to assess the effect of dietary dried partially destoned olive cake supplement on nutritional quality and sensory profile of milk and cheese produced by dairy cows. The experiment was carried out on eighty-four healthy dairy Friesian cows divided into two homogenous groups. The control group (CTR) received a conventional diet, whereas the experimental group (OC) received a conventional diet supplemented with olive cake as 15% of DM. The trial lasted five months. Monthly, on individual milk samples, yield and physical-chemical parameters were determined. Milk was used for the artisanal cheese production. On 10 samples of cheese for each group, physical-chemical and fatty acid profile were determined. Electronic nose analysis and sensory evaluation were performed. Data were analyzed by ANOVA. The diet affected (p < 0.05) the milk yield, exclusively in September. Yield and quality of cheese of OC group after 60 d of ripening showed higher (p < 0.05) yield, moisture and fat content, lower (p < 0.05) pH, protein, salt and ash content, higher (p < 0.01) MUFA and PUFA and CLA content, lower (p < 0.05) SFA, higher (p < 0.01) UFA/SFA and hypocholesterolemic/hypercholesterolemic ratios, better (p < 0.01) atherogenic and thrombogenic indices. Data show dietary olive cake supplementation in lactating dairy cows improves nutritional and nutraceutical properties of cheese, volatile profile and level of assessors’ acceptance.

Phenolic compounds and fatty acids content of some West Algerian olive oils

Olive represents the most widespread fruit cultivated in Algeria. Olive oil is the primary source of added fat in the Mediterranean diet with health benefits of which have been verified for millennia. Interest in phenolic compounds in olive oil has increased due to its antioxidant activity, which plays a very important role in human health. The present study is carried out to study the phenolic compounds and fatty acids profile of some olive oils from western Algeria. The quality parameters (acidity, peroxide value, K232, K270), tocopherol analysis, fatty acid composition and phenolic profile were determined by High performance chromatography (HPLC). The results showed that chemlal oil (SBA) recorded the highest level of tocopherol-α with 228.12 mg/Kg. Regarding the fatty acid composition, oleic acid was the most dominant, oil Oleaster (Bensekrane) records the highest percentage (72.80%) of oleic acid. The quantitative data on the phenolic content of the seven samples revealed that chemlal oil (SBA) had the highest level of polyphenols (328.99 mg/Kg). However, Sigoise oil (Sebra1) was characterized by the highest levels of tyrosol and hydroxytyrosol (15.89 mg/kg and 22.42 mg/kg, respectively). The highest concentrations of oleuropein derivatives and ligstroside derivatives were observed in chemlal oil (SBA) and the recoreded values were 105.97 mg/Kg and 83.49 mg/Kg, respectively. Chemlal oil (SBA) was characterized by the highest amount of lignans (35.93 mg/Kg), luteolin (10.16 mg/Kg) and apigenin (5.44 mg/Kg). Oleocanthal was found in all the tested samples and it was higher in Chemlal oil (102.43 mg/kg).

Compositional characteristics and oxidative stability of chia seed oil (Salvia hispanica L)

Fatty acid composition and triacylglycerols (TAG) profile of chia seed oil were determined. The main fatty acids present in the tested oil were α-linolenic acid (Ln, 61.1%) > linoleic acid (L, 16.6%) > palmitic acid (P, 6.7%) > oleic acid (O, 6.0%) > stearic acid (S, 3.2%). Five major triacylglycerols in chia oil were LnLnLn, LnLLn, LnLnP, LnOLn, and LLLn and these contributed more than 76% to the total. The oxidative stability under autoxidative and photooxidative conditions before and after the removal of their minor components was also determined. In addition, tocols, chlorophylls and carotenoids were measured in the oil. Oil samples were stripped of their minor components by using a facile silicic acid and charcoal in one pot rather than in a column. Storage under Schaal oven condition and photooxidation were also monitored for both crude oil (non-stripped) and stripped oil using stationary phase material. Total tocopherol contents were in the order of β−/γ- 282.68, δ- 47.44, and α-tocopherols 10.94 mg/kg of oil. Stripping removed all the minor components including tocopherols, chlorophylls and carotenoids. Oxidative stability of the tested seed oil was primarily affected by its composition of fatty acids, triacylglycerols, minor components, and storage conditions.Graphical abstract

Volatile components of deep-fried soybean oil as indicator indices of lipid oxidation and quality degradation

The present study investigated the lipid oxidation degree of soybean oil during regularly discontinuous 40 h-deep-frying process. Electron spin resonance (ESR) spectroscopy technique was applied to identify and quantify the formed radicals, along with evaluation of physicochemical parameters including acid value (AV), peroxide value (PV), p-anisidine value (p-AnV), polar compounds (PC), fatty acid composition and volatile profile. Results showed the AV, p-AnV, PC and free radical of frying oil samples increased significantly with the increasing frying time. The results of fatty acids showed that unsaturated fatty acid such as C18:1 and C18:2 decreased by 19.98% and 14.58%, respectively, with prolonged frying time, while the content of C16:1, trans C18:1 and C18:2 increased by 20.38%, 425% and 42.86%, respectively, when compared to the fresh oil samples. In contrast, the content of saturated fatty acid had little change. In total, 37 volatile compounds were detected revealing a complex aroma profile of frying soybean oil, composed of 15 aldehydes, 8 alcohols, 4 ketones, 4 acids, 5 alkanes and 1 furan. Principal component analysis and hierarchical clustering analysis indicated that hexanal, heptanal, (E)-2-hexenal, octanal, (E)-2-heptenal, nonanal, (E)-2-octenal, undecanal, (E,E)-2,4-heptadienal, (E)-2-decenal, 2-undecenal, (E,E)-2,4-decadienal, 1-pentanol, 2,2-dimethyl-3-hexanol, (Z)-2-dodecenol, 1-octen-3-ol, pentanoic acid, octanoic acid, nonanoic acid and 2-pentyl-furan may be potential markers for evaluating lipid oxidation of frying soybean oil.

Effect and mechanism of the algicidal bacterium Sulfitobacter porphyrae ZFX1 on the mitigation of harmful algal blooms caused by Prorocentrum donghaiense

Sulfitobacter porphyrae ZFX1, isolated from surface seawater of the East China Sea during a Prorocentrum donghaiense bloom recession, exhibits high algicidal activity against P. donghaiense. To evaluate the algicidal effect of ZFX1, the algicidal mode and stability were investigated. The results showed that ZFX1 indirectly attacked algae by secreting algicidal compounds, and the algicidal activity of the ZFX1 supernatant was insensitive to different temperatures, light intensities and pH values (pH 3–12). To explore the algicidal mechanism of the ZFX1 supernatant, its effects on the morphological and ultrastructural alterations, photosynthetic capacity, reactive oxygen species (ROS) and antioxidative system of P. donghaiense were investigated. Scanning and transmission electron microscopy revealed that the ZFX1 supernatant destroyed the algal cell membrane structure and caused intracellular leakage. The decrease in the chlorophyll a content and the marked declines in both the photosynthetic efficiency (Fv/Fm) and the electron transport rate (rETR) indicated that the ZFX1 supernatant could damage the photosynthetic system of P. donghaiense. The excessive production of ROS in algal cells demonstrated the oxidative damage triggered by the ZFX1 supernatant. Although the antioxidant defense system of P. donghaiense was activated to scavenge excessive ROS, lipid oxidation occurred. The fatty acid composition profile indicated that the ZFX1 supernatant markedly increased the contents of two saturated fatty acids and a monounsaturated fatty acid and decreased the proportion of two polyunsaturated fatty acids, which resulted in lipids with a lower degree of unsaturation (DU). The decline in the DU decreased the lipid fluidity and rigidified the membrane system, and these effects destroyed the function of the membrane system and ultimately resulted in algal cell death. Therefore, ZFX1 probably plays a key role in mitigating P. donghaiense bloom by inducing lipid oxidation, decreasing the DU of lipids and ultimately destroying the membrane systems of algal cells.