Palmitoleic Acid Content Research Articles

A potential gateway to understanding liver disease development: peripartum lipid fluctuations in dairy cows

Current lifestyles are leading to a worldwide increase in metabolic liver diseases that favor the development of liver disease. Changes in hepatocytes are caused by altered lipid concentrations, oxidative stress or toxicity by individual lipids. The complexity of the underlying processes and differences of the pathology to proposed rodent models makes the development of an effective targeted therapy difficult. The lipid mobilization that occurs in dairy cows in the postpartum period could be a natural model for the metabolic stress commonly observed in the development of liver diseases. We therefore used gas chromatography and histopathological staining techniques to analyze lipid patterns in diparous and multiparous cows during the peripartum period. The most striking change in lipid composition is the homogenous increase in palmitoleic acid (C16:1n7) content in all cows around the time of calving, with multiparous cows exhibiting consistently higher C16:1n7 levels by the end of the study. Elevated C16:1n7 levels have a potential key role in the development of non-alcoholic steatohepatitis (NASH) and tumorigenesis in the liver. Changes in C16:1n7, therefore, support the idea that lipid mobilization in dairy cows could serve as model for various liver diseases, such as nonalcoholic fatty liver disease (NAFLD) or NASH development.

A Flowering Morphological Investigation, Fruit Fatty Acids, and Mineral Elements Dynamic Changes of Idesia polycarpa Maxim.

Idesia polycarpa Maxim is a high-value species of fruit oil with edible, abundant linoleic acid and polyphenols. Idesia polycarpa is described as a dioecious species, and the flowers are male; female and bisexual flowers are produced on separate plants. In order to explore the flower types of Idesia polycarpa, the morphology of its flowers and inflorescence were investigated in this study. The flower and inflorescence types, the diameter, and the flowering sequencing in male and female inflorescence were determined. We also detected the length, width, and fresh weight of leaves, shoots, and female inflorescence, as well as the length and fresh weight of the petiole during the development. Additionally, we compared the length, width, the length/width ratio, and the flowering density between 5- and 7-year-old female trees. The phenological period observation of Idesia polycarpa showed that the development process can be roughly divided into 12 stages, including bud burst, leaf expansion, inflorescence growth, initial flowering, full flowering, flower decline, initial fruiting, fruit enlargement, fruit color change, fruit ripening, post-ripening of fruit, and leaf fall periods. Furthermore, four elites' fruit determined the oil content and the composition of fatty acid content during the development. The dynamic of fatty acids contents, the palrnitic acid, palmitoleic acid, stearic acid, oleic acid, and linolenic acid contents were detected during the fruit development of four elites. Moreover, the mineral elements content of fruit of four elites during development were determined. The patterns of vegetative and reproductive growth in young dioecious trees of Idesia polycarpa provided the theoretical basis for artificial pruning and training.

Using rice bran as a press aid during the cold-pressing of sesame seeds improved the extraction yield and quality of the resultant oil.

Simple, cost-effective, and practical techniques can enhance the shelf life of cold-pressed oils. This study evaluated sesame seed (SS) cold-pressed oil with various percentages of rice bran (RB) as press aid, including 0% (control or TSSO), 1% (T1), 2.5% (T2.5), 5% (T5), 7.5% (T7.5), and 10% (T10) w/w. The results demonstrated that adding RB considerably boosted extraction yields (p < .05), with 5% RB constituting the ideal combination. Adding 7.5% and 10% RB to the SS reduced free fatty acid (FFA) levels compared to the control sample. The oxidative stability index (OSI) and peroxide value (PV), however, significantly increased at combination ratios ranging from 2.5% to 10% (p < .05). Rice bran oil (TRBO) had the greatest OSI of all the studied oils, with 18.99 h, while the extracted oils showed an increase in OSI as RB contents rose. Total phenolic compounds (TPC), tocopherols, γ-oryzanol content, and total antioxidant activity (TAA) increased directly with the RB level. Despite the addition of RB altering the fatty acids concentration, linoleic and oleic acids continued to be the predominant fatty acids in TSSO, TRBO, and other extracted oil samples. Increasing the combination ratio increased the palmitic, palmitoleic, oleic, and linolenic acid content and decreased the stearic and linoleic acid content. In summary, the study demonstrated that the simultaneous cold-pressing of oil-bearing seeds and agro-industrial by-products is a potentially advantageous technique to increase the extraction yield, qualitative attributes, and shelf life of the extracted oils without the addition of synthetic antioxidants.

A study on some phytochemicals in Arthrospira platensis MGH-1 fortified with calcium and magnesium

ABSTRACT The effects of selected concentrations of calcium and magnesium on some of the phytochemicals in Arthrospira platensis MGH-1 were investigated. In order to produce A. platensis MGH-1 enriched with calcium and magnesium, the correct concentrations for each element were selected based on growth parameters and accumulation of these metals. Maximum soluble sugar, soluble protein, carotenoid, phenolic compound, and palmitic acid content were seen at 0.1 g L−1 calcium. The highest activity of catalase enzyme, chlorophyll a content, and the content of γ-linolenic acid and palmitoleic acid were detected at 1.2 g L−1 magnesium treatment. The results of the present study showed that 0.1 g L−1 of calcium and 1.2 g L−1 of magnesium are suitable element concentrations for the enrichment of A. platensis MGH-1 to develop antioxidant food rich in bioactive compounds for human health.

Fatty Acid Profile and Thermal Behavior of Fat-Rich Edible Insect Oils Compared to Commonly Consumed Animal and Plant Oils.

This study compared the physicochemical properties of edible insect oils from silkworm (Bombyx mori) pupa (SP), sago palm weevil (Rhynchophorus ferrugineus) larva (PW), and bamboo caterpillar (Omphisa fuscidentalis; BC) to oils from chicken skin (CK), beef back fat (BF), pork back fat (PF), salmon belly (SB), sea bass belly (BB), coconut (C), and peanut (P). The fatty acid profiles and thermal behaviors (crystallization and melting) of the extracted oils were evaluated. PW and BC oils had more saturated fatty acids (SFAs) than CK, PF, SB, BB, and P oils. SP oil had equivalent SFA content to CK and BB oils. Insect oils exhibited similar monounsaturated fatty acid concentrations in all samples, except C oils. PW and BC oils exhibited a higher content of palmitoleic acid than the other oils. SP oils contained polyunsaturated fatty acids similar to those in SB and BB oils, which were higher than those in PW, BC, CK, BF, and PF oils. SP oil also exhibited the highest concentration of α-linolenic acid (C18:3 n-3). Arachidonic acid (0.01-0.02 g/100 g) in all insect oils was lower level compared to CK, BF, PF, SB, and BB oils. SP oil (0.03 g/100 g) exhibited a slightly higher level of eicosapentaenoic acid compared to PW (0.01 g/100 g) and BC (0.01 g/100 g) oils. The insect oils were liquid at ambient temperature, solid below -15°C, and required less energy (△Hm-max) for melting than other samples. This study indicated that insects, particularly SP, could serve as an alternative source of fat to meet its growing demand.

Revealing the intrinsic relationship between microbial communities and physicochemical properties during ripening of Xuanwei ham

To clarify the relationship between microorganisms and physicochemical indicators of Xuanwei ham. Six ham samples for the first, second and third year were selected, respectively. The changes of physicochemical properties, the free fatty acids and microbial communities of Xuanwei ham were investigated by GC–MS and high-throughput sequencing technology. Results showed that scores of colour, overall acceptability, texture, taste and aroma were the highest in the third year sample. With increasing ripening time, moisture content, water activity (Aw), lightness (L*), springiness, and resilience decreased continuously, and yellowness (b*) was the highest in the second year sample. 31 free fatty acids were detected, and unsaturated fatty acids such as palmitoleic acid, oleic acid, and linoleic acid were the major fatty acids. The content of palmitoleic acid, oleic acid and eicosenoic acid increased significantly during processing. At the phylum level, the dominant bacteria were Proteobacteria and Firmicutes, and fungi were Ascomycota. At the genus level, the dominant bacteria were Staphylococcus and Psychrobacter, and fungi were Aspergillus. Correlation analysis showed that water content and Aw were closely related to microorganisms, and most unsaturated fatty acids were significantly correlated with microorganisms. These findings showed that microorganisms played an important role in the quality of Xuanwei ham, and provided a scientific basis for the quality control of Xuanwei ham.

Enzymatic Preparation, In-Depth Molecular Analysis, and In Vitro Digestion Simulation of Palmitoleic Acid (ω-7)-Enriched Fish Oil Triacylglycerols.

In this study, an enzymatic reaction was developed for synthesizing pure triacylglycerols (TAG) with a high content of palmitoleic acid (POA) using fish byproduct oil. The characteristics of synthesized structural TAGs rich in POA (POA-TAG) were analyzed in detail through ultrahigh-performance liquid chromatography Q Exactive orbitrap mass spectrometry. Optimal conditions were thoroughly investigated and determined for reaction systems, including the use of Lipozyme TL IM and Novozym 435, 15 wt % lipase loading, substrate mass ratio of 1:3, and water content of 2.5 and 0.5 wt %, respectively, resulting in yields of 67.50 and 67.45% for POA-TAG, respectively. Multivariate statistical analysis revealed that TAG 16:1/16:1/20:4, TAG 16:1/16:1/16:1, TAG 16:1/16:1/18:1, and TAG 16:0/16:1/18:1 were the main variables in Lipozyme TL IM and Novozym 435 enzyme-catalyzed products under different water content conditions. Finally, the fate of POA-TAG across the gastrointestinal tract was simulated using an in vitro digestion model. The results showed that the maximum release of free fatty acids and apparent rate constants were 71.44% and 0.0347 s-1, respectively, for POA-TAG lipids, and the physical and structural characteristics during digestion depended on their microenvironments. These findings provide a theoretical basis for studying the rational design of POA-structural lipids and exploring the nutritional and functional benefits of POA products.

The Quality Evaluation of Avocado Fruits (Persea americana Mill.) of Hass Produced in Different Localities on the Island of Tenerife, Spain.

The effect of the production area on the quality of Hass avocados grown on the island of Tenerife was studied. For this purpose, several physicochemical parameters, such as fruit weight, percentage of pulp, seed and skin, proximate composition, minerals, total phenolic compounds (TP), total flavonoid compounds (TF), α-tocopherol, antioxidant capacity, and fatty acid profile were analyzed. The location of the orchards significantly influenced avocado weight; pulp and seed percentage; and fat, fiber, ash, α-tocopherol, TP, phosphorus, potassium, calcium, iron, zinc, and oleic and palmitoleic acid contents. Buenavista (BU) avocados were the smallest (185 g) and presented the highest percentage of pulp (77.1%) and lowest percentage of fiber (5.43%). The highest levels of dry matter (33.8%) and fat (20.4%) were found in avocados harvested in Los Silos (SI) and Santiago del Teide (SA), respectively. Compared with those at the other locations, the avocados harvested in Güímar (GU) had high levels of α-tocopherol (52.2 µg g-1) and phenolic compounds (56.0 mg GAE 100 g-1). Avocados from Los Realejos (RE) had the highest percentage of oleic acid and the lowest percentage of palmitoleic acid. Numerous significant correlations were found between the variables studied, especially those between TP, TF, and antioxidant capacity (DPPH) and between fat percentage and dry matter.

Effect of Lupin Supplementation on the Growth, Carcass, and Meat Characteristics of Late-Fattening Hanwoo Steers.

This study aimed to investigate the effects of lupin flake supplementation on the growth, plasma parameters, carcass characteristics, and meat composition of late-fattening Hanwoo steers. The steers (n = 40) were randomly divided into the four groups with 10 steers each: LP0 (lupin flake 0%), LP3 (lupin flake 3%), LP6 (lupin flake 6%), and LP9 (lupin flake 9%). The total digestible nutriant intake increased as the concentration of lupin increased (linear and quadratic effects; p < 0.05). The thiobarbituric acid-reactive substance content in the strip loins decreased as lupin flake supplementation levels increased (linear and quadratic effects; p < 0.05), while carnosine levels increased linearly (p < 0.05). As the lupin flake supplementation level increased, anserine and creatinine contents increased linearly and quadratically (p < 0.05). Similarly, adenosine triphosphate (ATP) and adenosine monophosphate (AMP) content increased with increasing lupin flake supplementation levels in linear and quadratic effects (p < 0.001). Palmitoleic acid content increased significantly with increasing lupin flake supplementation level (linear and quadratic effects; p < 0.05). The content of oleic acid in the strip loin was not significant, but the unsaturated fatty acid (UFA) (p < 0.05) and n-6/n-3 ratio (p < 0.05) increased. The results of this study indicated that although lupin flake supplementation did not markedly affect the growth, carcass characteristics, or meat composition of late-fattening Hanwoo steers, it exerted a positive effect on the flavor, taste profiles (anserine, creatinine, ATP, and AMP), hypotonicity (TBARS), and healthy meat production (UFA and n-6/n-3 ratio) related to beef.

Tuning Fatty Acid Profile and Yield in Pichia pastoris.

Fatty acids have been supplied for diverse non-food, industrial applications from plant oils and animal fats for many decades. Due to the massively increasing world population demanding a nutritious diet and the thrive to provide feedstocks for industrial production lines in a sustainable way, i.e., independent from food supply chains, alternative fatty acid sources have massively gained in importance. Carbohydrate-rich side-streams of agricultural production, e.g., molasses, lignocellulosic waste, glycerol from biodiesel production, and even CO2, are considered and employed as carbon sources for the fermentative accumulation of fatty acids in selected microbial hosts. While certain fatty acid species are readily accumulated in native microbial metabolic routes, other fatty acid species are scarce, and host strains need to be metabolically engineered for their high-level production. We report the metabolic engineering of Pichia pastoris to produce palmitoleic acid from glucose and discuss the beneficial and detrimental engineering steps in detail. Fatty acid secretion was achieved through the deletion of fatty acyl-CoA synthetases and overexpression of the truncated E. coli thioesterase 'TesA. The best strains secreted >1 g/L free fatty acids into the culture medium. Additionally, the introduction of C16-specific ∆9-desaturases and fatty acid synthases, coupled with improved cultivation conditions, increased the palmitoleic acid content from 5.5% to 22%.

Palmitoleic Acid Extracted from Fish Oil Inhibit aGVHD By Immune Regulation

Objective: This study aims to explore the immunosuppressive effect of palmitoleic acid (POA), derived from fish oil extract, on lymphocytes in vitro and its potential impact on the clinical outcome and survival prognosis of rodents with acute graft-versus-host disease (aGVHD). Methods: In vitro experiments involved using CCK8 to determine the influence of various concentrations of POA on the growth and proliferation of lymphocytes. Flow cytometry was employed to assess POA's inhibitory effect on T lymphocyte activation triggered by fluorobol ester (PMA) and ionomycin (IM). For evaluating the therapeutic effect of POA on aGVHD, C57bl/c mice were used as donors and BALB/C mice as recipients. The aGVHD mouse model was established to observe the impact of POA on aGVHD treatment, survival, and prognosis. Results: In vitro experiments demonstrated that POA concentrations ranging from 250uM to 500uM inhibited the proliferation of PMA and IM-activated T lymphocytes and reduced the proportion of CD4+CD25+ cells without causing significant cytotoxicity. The aGVHD mouse model exhibited clinical symptoms like bristling, depilation, anal redness and swelling, and loose stools, along with characteristic pathological changes in the liver and small intestine. Treatment with POA significantly extended the survival period and reduced the clinical score of aGVHD in the model mice. Conclusion: Palmitoleic acid derived from fish oil shows promise as a potential treatment for acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation, warranting further research on its immunosuppressive properties. Keywords: Fish oil extract, palmitoleic acid, acute graft-versus-host disease, allogeneic hematopoietic stem cell transplantation, immunosuppression.

Effect of cultivar and environment on chemical composition and geographical traceability of Spanish olive oils

AbstractThis study aimed to investigate the influence of cultivar and environment on the chemical composition of Arbequina and Empeltre olive oils, and their contribution to geographical identification of olive oils from Aragon. A total of 260 olive oil samples from different cultivars (Arbequina, Empeltre, Royal de Calatayud, Alquezrana, and Royeta de Asque) from the three main oil‐producing areas of Aragon, located in northeast Spain, were selected. Fatty acid and sterol composition were analyzed in the course of three crop years (2017, 2018, and 2019). Cultivar was found the main factor influencing the variability of palmitic, palmitoleic, and linolenic fatty acid content, whereas geographic origin was the main contributor to variation in oleic and linoleic fatty acids in Arbequina and Empeltre olive oils. Cultivar also had a significant impact on sterol composition, although the effect of the production area also showed a significant effect on these oils. Crop year showed limited relevance, except for oleic and linoleic fatty acids. The interaction between the environment (e.g., crop year and geographical factors) and the cultivar (Arbequina and Empeltre) exerted a significant influence on oleic/linoleic (O/L) ratio and Δ7‐stigmastenol content, particularly in the southeast area of Aragon during the crop year with higher temperatures and drier conditions. Principal component analysis (PCA) and discriminant analysis (DA) confirmed the discriminative potential of the geographic production zone as a factor enabling the differentiation of olive oils from Aragon based on the major fatty acids and sterols.

Effects of di-(2-ethylhexyl) phthalate on growth, metabolism, and virulence of the plant pathogenic bacterium Acidovorax citrulli.

Acidovorax citrulli is a seed-borne bacterial pathogen that causes bacterial fruit blotch in cucurbits and severely affects the production of cucumbers and watermelons globally. In this study, we investigated the effects of di-(2-ethylhexyl) phthalate (DEHP) on the growth, metabolism, and virulence of A. citrulli. Bacterial population was not affected by DEHP exposure; moreover, significant changes were not observed in lipid peroxidation, membrane permeability, and nucleic acid leakage. However, palmitoleic acid content was increased in the cell membrane of DEHP-exposed A. citrulli. Further, DEHP exposure increased the activity of TCA cycle-related enzymes, including α-ketoglutarate dehydrogenase and succinyl-CoA synthetase, along with increase in the content of glutamate, succinate, fumarate, and malate in TCA cycle. Additionally, total 270 genes were differentially expressed by the treatment, of which 28 genes were upregulated and 242 genes, including those related to translation, flagellum-dependent cell motility, and flagellum assembly, were downregulated. Regarding virulence traits, swimming activity was decreased in DEHP-exposed A. citrulli; however, biofilm formation was not affected in in vitro assay. Moreover, relative expression of pathogenicity genes, including hrpX and hrpG, were decreased in DEHP-exposed A. citrulli compared to that of unexposed A. citrulli. Therefore, these results suggest that DEHP accumulation in soil could potentially influence the metabolism and virulence traits of A. citrulli.

Fatty acids and mineral composition of seed oils extracted from different Rosa L. taxa

In the study, the macro and micro elements and fatty acid contents in rose seeds, which are generally evaluated in the waste category, were determined. Among the plants belonging to these taxa, only the registered varieties belonging to four taxa were used, while the others were genotypes. The plant materials of the study include rosehip (R. canina L.), Yildiz variety of rosehip (R. canina L. cv ‘Yildiz’), Syrup rose (R. heckeliana Tratt. subsp. vanheurckiana), Austrian briar (R. foetida Herrm.), lax rootstock [R. caesia Sm. (Syn: R. laxa Retz.)], wild rose [R. montana subsp. woronovii Chaix subsp. woronovii (Lonacz) Ö. Nilsson L.], hybrid landscape roses (R. x hybrida) and Hosap rose [R. pisiformis (Christ) D.] taxa. It was determined that the contents of nitrogen, potassium, phosphorus, magnesium and calcium of the macro elements examined in the seed samples differed statistically from each other. The seeds of different Rosa L. species examined within the scope of the research can be considered as one of the fruit oil sources with its 3.71-10.01% oil content. The fatty acid contents were determined as follows: linoleic acid (ω6) contents in the taxa ranged from 41.63 to 50.11% with an average of 44.88%; oleic acid (ω9) ranged from 20.80 to 30.27% with an average of 24.95%; linolenic acid (ω3) varied between 14.00-28.51% with an average of 19.20%; arachidic acid ranged from 0.75-1.63% and the average was 1.97%; eicosenoic acid ranged between 0.13-0.65% and averaged 0.33%; palmitoleic acid contents ranged from 0.08-0.60; behenic acid varied between 0.08-0.19% with 0.11% average. It was observed that the (ω3/ω6 ratio of the hybrid rose, which is especially used as a landscape rose and whose fruits are not evaluated, had an average value. R. canina ‘Yildiz’ cultivar showed a high (ω3/ω6 ratio, which is important in health terms. The high oleic acid contents found in these taxa are important results.

Overproduction of palmitoleic acid from corn stover hydrolysate by engineered Saccharomyces cerevisiae

Palmitoleic acid (POA) has been widely applied to nutrition and pharmaceutical industry. However, high cost of scale-up fermentation restricts the extensive application of POA. Hence, we investigated the availability of corn stover hydrolysate (CSH) as carbon source in POA production by engineered S. cerevisiae. Although the yeast growth was inhibited to some extent by CSH, the POA production with CSH was slightly higher than that with pure glucose. The C/N ratio of 120 and addition of 1 g/L lysine raised the POA titer up to 2.19 g/L and 2.05 g/L, respectively. Two-stage cultivation could increase the POA titer by upregulating the gene expression of key enzymes in fatty acid synthesis pathway. A high POA content of 57.5% (v/v) and a highest POA titer of 6.56 g/L were achieved under the optimized conditions. These findings provide a feasible approach for sustainable production of POA or its derivatives from CSH.

Antioxidant action of yerba mate on carcass and meat characteristics and fatty acid profile in meat and fat of lambs finished in tropical pastures

The objective was to evaluate the effect of the supplementation with natural antioxidants from Yerba mate (Ilex paraguariensis St. Hil.) on the performance, carcass and meat characteristics, and fatty acid profile in meat and fat of Texel × Ile de France lambs kept in Brachiaria-grass pasture. Twenty lambs with a mean age of 90days and 26.3kg of BW were distributed in a completely randomized design in two treatments with 10 replicates/treatment: Control-protein-energy supplement based on corn and soybean meal (150g/kg DM of crude protein) without the addition of natural antioxidant yerba mate and Yerba Mate - energy protein supplement with the addition of yerba mate (110g/kg DM). There was no treatment effect on animal performance and carcass characteristics. The subcutaneous fat thickness was significantly higher for lambs treated without yerba mate. There was no effect of nutritional treatments on the oxidative markers of lamb meat. The muscle of the animals treated with yerba mate showed a higher concentration of unsaturated and polyunsaturated fatty acids elaidic, linolenic, thymnodonic, docosadienoic, and ceorvonic. The fat of the animals treated with yerba mate showed a higher concentration of palmitoleic acid, linoelaidic acid, heneicosanoic acid, dihomo-γ-linolenic acid, and arachidonic acid. The concentration of polyunsaturated fatty acids was significantly higher in meat and fat of lambs treated with yerba mate. Including yerba mate in the diet of lambs kept on Brachiaria pastures improves the lipid profile of polyunsaturated fatty acids in meat and fat, without altering the performance of the animals.

Characterization of bluefish baits (keeled mullet, leaping mullet, and sardine) in regard to biochemical and physical properties: bait preference of bluefish

The fishing industry needs alternative baits that are not based on resources available for human consumption. In order to develop artificial baits, first the preferred baits should be determined, and then their biochemical and physiological composition should be identified. The aim of this study was to determine bluefish bait preferences and reveal the biochemical composition and physical characteristics of the preferred baits. In this study, keeled mullet, leaping mullet, and sardine species were found to have the highest catch, respectively. The highest texture hardness and whiteness colour values were found in keeled mullet, which had the highest catch efficiency for bluefish fishing. The highest palmitoleic acid content was found in keeled mullet at 25.86% (16.93% in leaping mullet and 17.05% in sardine). However, the highest PUFA content was found in sardine (15.56%), followed by leaping mullet (13.97%), and then keeled mullet (11.32%). As for the amino acid compositions, it was determined that glutamic acid and serine content, which are known to have positive effects on feed intake, were higher in keeled mullet. In regard to volatile components, mullet species were especially rich in total alcohol, aldehyde, ketone, and amines, while sardines were rich in hydrocarbons and furans. Hexanal and heptanal compounds, known as fish aroma, were determined at high rates in keeled mullet. It can be concluded that these components may be attractive to bluefish. The data presented in this study may be useful for the production of artificial bait.

Lipid production characteristics of a newly isolated microalga Asterarcys quadricellulare R-56 as biodiesel feedstock.

In this study, a new microalgal strain, Asterarcys quadricellulare R-56, was isolated for biomass and lipid production. The effects of carbon and nitrogen sources and initial pH on the cell growth and lipid accumulation of strain R-56 were investigated. At 10g L-1 glucose, 0.6g L-1 sodium nitrate, and pH 7, the highest biomass of 4.18g L-1 and lipid content of 43.66% were obtained. Microalgae had a broad pH tolerance in the range of 5-11, and the pH of the culture medium was close to neutral at the end of cultivation. The maximum contents of chlorophyll, carbohydrate, and protein under the recommended culture conditions were 19.47mgmL-1, 21.80%, and 29.94%, respectively. Palmitic and palmitoleic acid contents in strain R-56 accounted for as high as 83.73% of total fatty acids. This study suggested that strain R-56 was a promising lipid producer for high-quality biodiesel production.

Production of palmitoleic acid by oleaginous yeast Scheffersomyces segobiensis DSM 27193 using systematic dissolved oxygen regulation strategy

Palmitoleic acid (POA) can be naturally found only in few oil seeds and has significant applications in pharmaceutical industry. Recently, the isolated oleaginous yeast Scheffersomyces segobiensis DSM 27193 was identified with high content of POA in its intracellular lipid (13.80%). In this study, process optimization focused on dissolved oxygen regulation to improve POA production was conducted. Dynamic agitation was found to do significant enhancement on POA-rich lipid production than aeration regulation. Under the best condition of 1000 r·min−1 of agitation and 1 vvm (airvolume/culture volume/min) of aeration, no ethanol was detected during the whole fermentation process, while a dry biomass concentration of 44.80 g·L−1 with 13.43 g·L−1 of lipid and 2.93 g·L−1 of POA was achieved. Transcription analysis revealed that the ethanol synthetic pathway was downregulated under the condition of high agitation, while the expression of the key enzymes responsible for lipid and POA accumulation were enhanced.

Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep.

The aim of this study was to investigate the impacts of inulin and Chinese gallotannin on the meat fatty acids and urinary metabolites in sheep. Twenty-four healthy (25.80 ± 3.85 kg) weaned Hu lambs of approximately 4.5 months old were equally divided into four groups: control group (basal diet), treatment group I (basal diet + 0.1% inulin), treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin), and treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG). The contents of myristic acid (C14:0) and palmitic acid (C16:0) were found to be lower in treatment group II than in the control group (p < 0.05). Moreover, the palmitoleic acid (C16:1) content in treatment group II was notably higher than that in the control group (p < 0.05), while the elaidic acid (C18:1n9t) content in treatment group II was higher than that in other groups (p < 0.05). Besides, the linoleic acid (C18:2n6c) content was higher in the treatment II and control groups than in the treatment I and III groups. Furthermore, compared with the control group, both 4-pyridoxic acid and creatinine in treatment groups I and II were upregulated (p < 0.05), while other metabolites, such as nicotinuric acid, l-threonine, palmitic acid, and oleic acid, were drastically downregulated (p < 0.05). These differential metabolites were found to be mainly involved in nicotinate and nicotinamide metabolism (ko00760), vitamin B6 metabolism (ko00750), and the fatty acid biosynthesis pathway (ko00061). It is concluded that the combination of inulin and Chinese gallotannin in the diet could improve the energy and lipid metabolism of sheep, which may improve both mutton quality and production performance.