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In this study, the antioxidant activity of soursop flowers extract in delaying palm olein oxidation at frying temperature was assessed. The oil was supplemented with the extract at concentrations 200â1800 ppm, and stored in the oven at 180 °C for 6 days (4 h heating per day). Palm olein containing butylated hydroxytoluene (BHT) served as positive control while the same oil without antioxidant (Control) served as negative one, in order to monitor changes in oils. After each two heating days, oil samples were collected, and their chemical indexes were determined. Peroxide, para-anisidine, TOTOX, thiobarbituric acid and iodine values were the parameters evaluated. Additionally, the evolution of the fatty acid composition of each oil sample during the storage was assessed by gas-chromatography using a flame ionization detector (GC/FID). Generally, palm olein samples containing the natural extract have exhibited the lowest rate of oxidation, and were efficient in limiting the destruction of unsaturated fatty acids in oil at frying temperature. The order of effectiveness in inhibiting oil oxidation was the following: PO + AnM1800ppm> PO + AnM1400ppm> PO + AnM1000ppm > PO + An.M600ppm> PO + An.M200ppm> PO + BHT200ppm = Control. From these results, it can be concluded that soursop flowers are a potent sources of natural antioxidants for stabilization of palm olein. Keywords: Soursop flowers, Stabilization, Natural antioxidant, Palm olein, Frying, Oxidative stability

In this study, fatty acid compositions of phyto-zooplankton (calanoid copepod species, krill…) to fish species (mackerel, sardine anchovy, salmon, shark) are presented. Marine oils are essentially used for their high long-chain polyunsaturated fatty acids (LC-PUFA), namely eicosapentaenoic (EPA) and docosahexaenoic (DHA) for their good health impact. Due to health benefits of the omega-3, weekly fish consumption is today recommended by many authorities (FDA, AFSSA…). Capture fisheries and aquaculture supplied the world with about 110 million tonnes of food fish in 2006 (FAO 2009), providing an apparent per capita supply of 16.7 kg. It is well established that the lipid composition of fish muscle is influenced by the diet and also depends on the effects of environmental factors (temperature, oxygen concentration in sea water) and endogenous medium (physiological state and individual variability). In general, cultured fish have been reported to have a softer texture than wild fish, which has been related to the differences in muscle structure, proximate composition and nutritional value. New applications of typical compounds (wax esters, squalene …) or lipid classes (glycerophospholipids, ether glycerolipids, sphingophospholipids …) as cosmetics, functional foods and dietary supplements will become very important in the near future with nano-structured drug carriers in pharmaceutical and biomedical areas.

The objective of this paper is to present the beneficial aspects of some insects consumed in sub-Saharan Africa, based on examples of insects consumed in Cameroon, to present their potential as sources of lipids and essential fatty acids. In Africa, termites, larvae of raphia weevil, caterpillars, crickets, bees, maggots, butterflies, weevil, etc. are significant sources of food. These insects belong mainly to the orders of : Isoptera, Orthoptera, Dictyoptera, Coleoptera, Hymenoptera, Lepidoptera and Diptera. Depending on the species, insects are rich in proteins, minerals (K, Ca, Mg, Zn, P, Fe) and/or vitamins (thiamine/B1, riboflavine/B2, pyridoxine/B6, acid pantothenic, niacin). The composition of oils extracted from the following six insects consumed in Cameroon was investigated : larvaes of raphia weevil (Rhynchophorus phoenicis), crickets (Homorocoryphus nitidulus), grasshopper (Zonocerus variegates), termites (Macrotermes sp.), a variety of caterpillars (Imbrasia sp.) and an unidentified caterpillar from the forest (UI carterpillar). The extraction yields of oil were 53.75%, 67.25%, 9.12%, 49.35%, 24.44% and 20.17% respectively for raphia weevil larvae, crickets, devastating crickets, termites, Imbrasia and UI caterpillar. The oil from raphia weevil mainly contains 37.60% of palmitoleic acid and 45.46% of linoleic acid. The oil from crickets is principally made up of palmitoleic acid (27.59%), linoleic acid (45.63%) and α-linolenic acid (16.19%). The oil from grasshoppers is composed of palmitoleic acid (23.83%), oleic acid (10.71%), linoleic acid (21.07%), α-linolenic acid (14.76%) and γ-linolenic acid (22.54%). The main components of termite oil are : palmitic acid (30.47%), oleic acid (47.52%) and linoleic acid (8.79%). Palmitic acid (36.08%) and linolenic acid (38.01%) are the two dominant fatty acids of Imbrasia oil. As Imbrasia oil, UI caterpillar oil is composed of palmitic acid (30.80%) and linolenic acid (41.79%). Stearic acid (7.04%), oleic acid (8.56%) and linoleic acid (6.59%) are also present. These results show that these insects are considerable sources of fat. Their oils are rich in polyunsaturated fatty acids, of which essential fatty acids are linoleic and linolenic acids. The ratio PUFA/SFA, in the majority of cases is higher than 0.8, associated with desirable levels of cholesterol.

The role of isolated fatty acids on human health has long been studied by the nutritionists. The consequence of this research for the food industry was a need for a better control of the lipidic profile of manufactured food products. The purpose of the present paper was to give the nutritional profile of 53 vegetable oils in relation with their fatty acid composition and their related nutritional potential. In a first section, the role of isolated fatty acids on blood lipids (LDL-Cholesterol, HDL-Cholesterol and triacylglycerols) has been reviewed. In a second section, the vegetable oils are gathered in relation with their similar fatty acids composition, with the aim of classifying their properties in accordance with their role on blood lipids. From a nutritional point of view, besides the major α-linolenic acid source that is rapeseed oil, the classification makes some interesting sources to stand out. They contain either mainly α-linolenic acid (camelin, linseed and perilla) or both essential fatty acids as α-linolenic and linoleic acids (purslane, chia, salicorna and sea buckthorn seeds). Moreover, this collection is an interesting tool for new designed food products with a better lipid composition.

The effect of deep fat frying dehydration conditions of shea kernels on the composition and properties of the unsaponifiable fraction of its butter was carried out by using a central composite experimental design. Both content and composition of the unsaponifiable matters depend on the thickness of kernels, the temperature of frying, the kernels/butter weight ratio and the time of frying. Butters with high content of unsaponifiable (> 6%) are extracted from the kernels with thickness less than 10 mm fried at less than 150 °C. The content of triterpenic alcohols is over 70% in low temperature frying conditions (< 150 °C) of kernels of thickness under 10mm, fried during 4-8 minutes under a weight ratio lower than 0.060. The quantity of hydrocarbons is between 4 and 57%, depending on frying conditions of the kernels. The best result is obtained by frying during 2-8 minutes kernels with less than 8 mm of thickness at a temperature less than 150 °C in a kernels/butter ratio of 0.035-0.060. The sterols content remains lower than 7%depending on the frying conditions by 68%.

The n-3 fatty acids are unanimously considered as high nutritional value molecules, especially Long-Chains PUFA from marine origin. However, most of the products available in the market contain LC-PUFA esterified on the glycerol under the common form of triacylglycerols. Another interesting way can be to esterify the PUFA on polar lipids and especially on Phospholipids. An original patented enzymatic process carried out under mild conditions (low temperature, no use of organic solvent) is presented to produce at industrial scale a Phospho-Lipo-Peptidic Complex, that is particularly rich in DHA esterified on the sn-2 position on PL.

The purpose of this paper was to take stock of the economic situation on the co-products coming from the fish factories. Such co-products contain large amounts of long-chain polyunsaturated fatty acids (LC-PUFA), mainly docosahexaenoic acid (C22 :6 n-3) and eicosapentaenoic acid (C20 :5 n-3). Several extraction processes (thermal treatments, solvent extraction, enzymatic methods) are taking place, considering the importance of these components in human health. Some amphiphilic molecules, which contain high amounts of LC-PUFA may find outlets in nutraceutics, cosmetics and in the food industry, provided their safety and quality are guaranteed.

Membrane separative techniques as candidates for alternative “green” processing of Oils and Fats present several advantages like energy saving, friendliness to environment and quality preservation of the final products. However, despite the considerable number of research programs carried out on several steps of the processing, including refining, desolvantisation and fractionation, no significant industrial development has been observed. Pointing out the lack of fundamental understanding of the mechanisms that rule the separations in hydrophobic media, a renewed approach of the membrane partition based on the relative hydrophobicity of lipids molecules vs barrier materials has been set up. Starting from an electronic analogy, a hydrophobic/hydrophilic valve has been designed by using a polar molecules coating on a porous material surface. The experimental realisation based on a two-compartments cell allowed to obtain preliminary results on the separation of the oily and water phases of an emulsion, that is a very promising result.

New concerns have appeared recently from the European and American consumers about quality, safety and environmental impact of the food products. In the particular case of European countries, the coming back of traditional products with a high sentimental value should be noticed. To fit the forthcoming demand of the consumer, the Oils and Fats industry have to develop a new approach based on alternative technologies that may emerge from the research with very specific objectives: no solvents, mild technologies, less energy consumption and final wastes. The purpose of this article is to discuss about the new biological tools capable to generate alternative ways for the oil elaboration: use of enzymes for destructuration of the vegetal or animal tissues and the subsequent utilisation of membrane techniques for the separation and purification steps. These new technologies involving less heat and mechanical stress to the oil, lead to a better “native” quality of the final products. However, fundamental research is needed on the separation mechanisms of those complex mixtures to optimise the process and prepare the transfer to the industrial conditions. The present article reports a contribution on the aqueous extraction of rapeseed oil as an example

Les huiles marines représentent des sources potentielles d’acides gras polyinsaturés (AGPI) dont les implications au niveau de la nutrition et de la santé sont avérées. Ces molécules sont extraites à partir de poissons, algues ou co-produits de la filière halieutique par des procédés de cuisson-pression, en présence de solvants ou par des techniques enzymatiques beaucoup moins drastiques. Des fractions plus ou moins purifiées en AGPI sont obtenues par cristallisation à froid, en présence de solvants organiques, complexation avec de l’urée, distillation moléculaire ou extraction par fluide supercritique. L’utilisation de lipases stéréospécifiques dans des procédés d’hydrolyse et d’estérification conduit à une diversité de molécules d’acylglycérols riches en AGPI trouvant de nombreuses applications dans le domaine de l’agroalimentaire et de la santé.

Les lipides polaires marins, notamment les phospholipides (PL), retiennent depuis quelques années l’attention des chercheurs et des industriels en raison de leur composition, particulièrement riche en acides gras polyinsaturés à longue chaîne (AGPI-LC). Ils combinent ainsi les propriétés reconnues des AGPI-LC à l’intérêt métabolique et structural des phospholipides. Les sources sont nombreuses et d’accès très diversifié. Le défi industriel provient de leurs caractéristiques amphiphiles et aromatiques particulièrement marquées qui rend leur extraction très difficile.

Extraction and concentration of polyunsaturated fatty acid from salmon oil (Salmo salar) by enzymatic hydrolysis were studied. Enzymatic aqueous extraction of oil with Neutrase® 0.5l was applied to the salmon flesh in batch reactor. Reaction kinetics were monitored under nitrogen by measuring the degree of hydrolysis (DH%) using the pH-stat method, in order to preserve the functional and nutritional values of hydrolysates. Lipids were separated by centrifugation yielding 14.3% (w/w) for the product, compared to 15.2% (w/w) obtained using the classical method with solvent. Lipase hydrolysis by Novozym® SP 398, a specific sn-1, sn-3 enzyme, and membrane filtration, were evaluated as means of selectively concentrating polyunsaturated fatty acids (PUFA) fractions. A Doehlert matrix was used to study the effect of reaction time, flow and enzyme/protein ratio. Quadratic models were used to generate response surfaces of the liberation of fatty acids during the lipolysis and the composition of major saturated and polyunsaturated fatty acids in the permeate.

Abstract Background Nano-emulsions, as non-equilibrium systems, present characteristics and properties which depend not only on composition but also on their method of preparation. To obtain better penetration, nanocosmeceuticals use nano-sized systems for the delivery of active ingredients to targeted cells. In this work, nano-emulsions composed of miglyol, rapeseed oil and salmon oil were developed as a cosmetic matrix. Measurements of different physico-chemical properties of nano-emulsions were taken according to size, electrophoretic mobility, conductivity, viscosity, turbidity, cristallization and melting point. The RHLB was calculated for each formulation in order to achieve maximum stability. Results Both tween 80 and soya lecithin were found to stabilize formulations. The results showed that rapeseed oil and miglyol are the predominant parameters for determining the expression of results concerning the characterization of emulsion. Based on the mixture design, we achieved the optimal point using the following formulation: 56.5% rapessed oil, 35.5% miglyol, and 8% salmon oil. We considered this formulation to be the best as a nanocosmeceutical product due to the small size, good turbidity, and average HLB. Conclusions This study demonstrates the influence of formulation on the physico-chemical properties of each nano-emulsion obtained by the mixture design.

Abstract: Thrombotic microangiopathy (TMA) is characterized by immunothrombosis and life-threatening organ failure but the precise underlying mechanism driving its pathogenesis remains elusive. In this study, we hypothesized that gasdermin D (GSDMD), a pore-forming protein that serves as the final downstream effector of the pyroptosis/interleukin-1β (IL-1β) pathway, contributes to TMA and its consequences by amplifying neutrophil maturation and subsequent necrosis. Using a murine model of focal crystalline TMA, we found that Gsdmd deficiency ameliorated immunothrombosis, acute tissue injury, and failure. Gsdmd-/- mice exhibited a decrease in mature IL-1β, as well as in neutrophil maturation, β2-integrin activation, and recruitment to TMA lesions, in which they formed reduced neutrophil extracellular traps in both arteries and interstitial tissue. The GSDMD inhibitor disulfiram dose-dependently suppressed human neutrophil pyroptosis in response to cholesterol crystals. Experiments with GSDMD-deficient, human-induced, pluripotent stem cell-derived neutrophils confirmed the involvement of GSDMD in neutrophil β2-integrin activation, maturation, and pyroptosis. Both prophylactic and therapeutic administration of disulfiram protected the mice from focal TMA, acute tissue injury, and failure. Our data identified GSDMD as a key mediator of focal crystalline TMA and its consequences, including ischemic tissue infarction and organ failure. GSDMD could potentially serve as a therapeutic target for the systemic forms of TMA., (© 2024 American Society of Hematology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.)

The human bone marrow (BM) niche sustains hematopoiesis throughout life. We present a method for generating complex BM-like organoids (BMOs) from human induced pluripotent stem cells (iPSCs). BMOs consist of key cell types that self-organize into spatially defined three-dimensional structures mimicking cellular, structural and molecular characteristics of the hematopoietic microenvironment. Functional properties of BMOs include the presence of an in vivo-like vascular network, the presence of multipotent mesenchymal stem/progenitor cells, the support of neutrophil differentiation and responsiveness to inflammatory stimuli. Single-cell RNA sequencing revealed a heterocellular composition including the presence of a hematopoietic stem/progenitor (HSPC) cluster expressing genes of fetal HSCs. BMO-derived HSPCs also exhibited lymphoid potential and a subset demonstrated transient engraftment potential upon xenotransplantation in mice. We show that the BMOs could enable the modeling of hematopoietic developmental aspects and inborn errors of hematopoiesis, as shown for human VPS45 deficiency. Thus, iPSC-derived BMOs serve as a physiologically relevant in vitro model of the human BM microenvironment to study hematopoietic development and BM diseases., (© 2024. The Author(s).)

Mitochondrial metabolism is critical in hematopoietic stem cell maintenance and differentiation. Here, we present a step-by-step protocol to efficiently differentiate human induced pluripotent stem cells into myeloid progenitors by a robust feeder- and serum-free system. Furthermore, we provide a protocol to subsequently assess mitochondrial function in iPSC-derived myeloid progenitors. We comprehensively describe a protocol to analyze and to quantify key parameters of mitochondrial respiration of iPSC-derived myeloid progenitors by the Seahorse XFe96 Analyzer. Additionally, our protocol includes extensive troubleshooting suggestions. For complete details on the use and execution of this protocol, please refer to Fan et al. (2022). 1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The mechanisms of coordinated changes in proteome composition and their relevance for the differentiation of neutrophil granulocytes are not well studied. Here, we discover 2 novel human genetic defects in signal recognition particle receptor alpha (SRPRA) and SRP19, constituents of the mammalian cotranslational targeting machinery, and characterize their roles in neutrophil granulocyte differentiation. We systematically study the proteome of neutrophil granulocytes from patients with variants in the SRP genes, HAX1, and ELANE, and identify global as well as specific proteome aberrations. Using in vitro differentiation of human induced pluripotent stem cells and in vivo zebrafish models, we study the effects of SRP deficiency on neutrophil granulocyte development. In a heterologous cell-based inducible protein expression system, we validate the effects conferred by SRP dysfunction for selected proteins that we identified in our proteome screen. Thus, SRP-dependent protein processing, intracellular trafficking, and homeostasis are critically important for the differentiation of neutrophil granulocytes., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

The relevance of molecular mechanisms governing mitochondrial proteostasis to the differentiation and function of hematopoietic and immune cells is largely elusive. Through dissection of the network of proteins related to HCLS1-associated protein X-1, we defined a potentially novel functional CLPB/HAX1/(PRKD2)/HSP27 axis with critical importance for the differentiation of neutrophil granulocytes and, thus, elucidated molecular and metabolic mechanisms underlying congenital neutropenia in patients with HAX1 deficiency as well as bi- and monoallelic mutations in CLPB. As shown by stable isotope labeling by amino acids in cell culture (SILAC) proteomics, CLPB and HAX1 control the balance of mitochondrial protein synthesis and persistence crucial for proper mitochondrial function. Impaired mitochondrial protein dynamics are associated with decreased abundance of the serine-threonine kinase PRKD2 and HSP27 phosphorylated on serines 78 and 82. Cellular defects in HAX1-/- cells can be functionally reconstituted by HSP27. Thus, mitochondrial proteostasis emerges as a critical molecular and metabolic mechanism governing the differentiation and function of neutrophil granulocytes.

During mitotic exit, thousands of nuclear pore complexes (NPCs) assemble concomitant with the nuclear envelope to build a transport-competent nucleus. Here, we show that Nup50 plays a crucial role in NPC assembly independent of its well-established function in nuclear transport. RNAi-mediated downregulation in cells or immunodepletion of Nup50 protein in Xenopus egg extracts interferes with NPC assembly. We define a conserved central region of 46 residues in Nup50 that is crucial for Nup153 and MEL28/ELYS binding, and for NPC interaction. Surprisingly, neither NPC interaction nor binding of Nup50 to importin α/β, the GTPase Ran, or chromatin is crucial for its function in the assembly process. Instead, an N-terminal fragment of Nup50 can stimulate the Ran GTPase guanine nucleotide exchange factor RCC1 and NPC assembly, indicating that Nup50 acts via the Ran system in NPC reformation at the end of mitosis. In support of this conclusion, Nup50 mutants defective in RCC1 binding and stimulation cannot replace the wild-type protein in in vitro NPC assembly assays, whereas excess RCC1 can compensate the loss of Nup50., (© 2021 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)

Vacuolar protein sorting 45 homolog (VPS45), a member of the Sec1/Munc18 (SM) family, has been implicated in the regulation of endosomal trafficking. VPS45 deficiency in human patients results in congenital neutropenia, bone marrow fibrosis, and extramedullary renal hematopoiesis. Detailed mechanisms of the VPS45 function are unknown. Here, we show an essential role of mammalian VPS45 in maintaining the intracellular organization of endolysosomal vesicles and promoting recycling of cell-surface receptors. Loss of VPS45 causes defective Rab5-to-Rab7 conversion resulting in trapping of cargos in early endosomes and impaired delivery to lysosomes. In this context, we demonstrate aberrant trafficking of the granulocyte colony-stimulating factor receptor in the absence of VPS45. Furthermore, we find that lack of VPS45 in mice is not compatible with embryonic development. Thus, we identify mammalian VPS45 as a critical regulator of trafficking through the endosomal system and early embryogenesis of mice., (© 2021 by The American Society of Hematology.)

Living systems integrate biochemical reactions that determine the functional state of each cell. Reactions are primarily mediated by proteins. In proteomic studies, these have been treated as independent entities, disregarding their higher-level organization into complexes that affects their activity and/or function and is thus of great interest for biological research. Here, we describe the implementation of an integrated technique to quantify cell-state-specific changes in the physical arrangement of protein complexes concurrently for thousands of proteins and hundreds of complexes. Applying this technique to a comparison of human cells in interphase and mitosis, we provide a systematic overview of mitotic proteome reorganization. The results recall key hallmarks of mitotic complex remodeling and suggest a model of nuclear pore complex disassembly, which we validate by orthogonal methods. To support the interpretation of quantitative SEC-SWATH-MS datasets, we extend the software CCprofiler and provide an interactive exploration tool, SECexplorer-cc., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

During interphase, the nuclear envelope (NE) serves as a selective barrier between cytosol and nucleoplasm. When vertebrate cells enter mitosis, the NE is dismantled in the process of nuclear envelope breakdown (NEBD). Disassembly of nuclear pore complexes (NPCs) is a key aspect of NEBD, required for NE permeabilization and formation of a cytoplasmic mitotic spindle. Here, we show that both CDK1 and polo-like kinase 1 (PLK1) support mitotic NPC disintegration by hyperphosphorylation of Nup98, the gatekeeper nucleoporin, and Nup53, a central nucleoporin linking the inner NPC scaffold to the pore membrane. Multisite phosphorylation of Nup53 critically contributes to its liberation from its partner nucleoporins, including the pore membrane protein NDC1. Initial steps of NPC disassembly in semi-permeabilized cells can be reconstituted by a cocktail of mitotic kinases including cyclinB-CDK1, NIMA, and PLK1, suggesting that the unzipping of nucleoporin interactions by protein phosphorylation is an important principle underlying mitotic NE permeabilization., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

The preparation of eukaryotic cells for division requires an extensive cellular reorganization, affecting cytoskeletal elements, chromatin, and organelles. These drastic changes in cellular architecture ensure the proper segregation of chromosomes and inheritance of organelles. The morphological alterations occurring during mitotic entry are tightly coordinated with the cell cycle, mainly through the action of mitotic kinases. Conversely, the fidelity of these processes impacts mitotic progression and is important for organismal homeostasis and cell fate. Here, we provide an overview of major architectural changes observed during early mitosis and review recent progress in understanding their regulatory mechanisms, focusing on processes accompanying mitotic cell rounding and restructuring of organelles in mammalian cells., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Escherichia coli grew in a minimal medium on propionate as the sole carbon and energy source. Initially a lag phase of 4-7 days was observed. Cells adapted to propionate still required 1-2 days before growth commenced. Incorporation of (2-13C), (3-13C) or (2H3)propionate into alanine revealed by NMR that propionate was oxidized to pyruvate without randomisation of the carbon skeleton and excluded pathways in which the methyl group was transiently converted to a methylene group. Extracts of propionate-grown cells contained a specific enzyme that catalyses the condensation of propionyl-CoA with oxaloacetate, most probably to methylcitrate. The enzyme was purified and identified as the already-known citrate synthase II. By 2-D gel electrophoresis, the formation of a second propionate-specific enzyme with sequence similarities to isocitrate lyases was detected. The genes of both enzymes were located in a putative operon with high identities (at least 76% on the protein level) with the very recently discovered prp operon from Salmonella typhimurium. The results indicate that E. coli oxidises propionate to pyruvate via the methylcitrate cycle known from yeast. The 13C patterns of aspartate and glutamate are consistent with the further oxidation of pyruvate to acetyl-CoA. Oxaloacetate is predominantly generated via the glyoxylate cycle rather than by carboxylation of phosphoenolpyruvate.