Diacylglycerol (DAG), a functional lipid with two isomers, exhibits distinct physical properties that affect oil systems. This study investigated the crystallization behaviors and physical property stabilities in binary systems composed of sn-1,3 DAG and its migration equilibrium product (ME-DAG, with an sn-1,3 DAG:sn-1,2 DAG ratio of 65:35) at mass ratios of 20 %, 50 %, and 80 % with palm kernel oil (PKO). The results revealed that the sn-1,3 DAG/PKO systems exhibited faster crystallization rates and more pronounced eutectic effects than the ME-DAG/PKO systems. In addition, sn-1,3 DAG inhibited the polymorphic transformation (α → β' → β) in the DAG/PKO binary systems. Higher DAG concentrations enhanced the crystallization and nucleation rates. Furthermore, sn-1,3 DAG at 50 % and 80 % notably reduced post-hardening and moderated the slope of the solid fat content curve. Microscopic analysis revealed the presence of Maltese cross crystals and disordered acicular crystals in the DAG/PKO binary systems. These findings underscore the critical role of DAG acyl migration in compatibility, crystallization kinetics, polymorphism, and texture, offering insights for developing functional plastic lipids with tailored properties.
Diacylglycerols (DAG) of varying chain lengths were synthesized and the acyl migrated samples with different 1,3-DAG/1,2-DAG ratios were obtained. The crystallization profile and surface adsorption differed depending on DAG structure. C12 and C14 DAGs formed small platelet- and needle-like crystals at the oil-air interface which can better reduce surface tension and pack in an ordered lamellar structure in oil. The acyl migrated DAGs with higher ratios of 1,2-DAG showed reduced crystal size and lower oil-air interfacial activity. C14 and C12 DAG oleogels exhibited higher elasticity and whipping ability with crystal shells surrounding bubbles, whereas C16 and C18 DAG oleogels had low elasticity and limited whipping ability due to the formation of aggregated needle-like crystals and loose gel network. Thus, acyl chain length dramatically influences the gelation and foaming behaviors of DAGs whereas the isomers exert little influence. This study provides basis for applying DAG of different structures in food products.
The microstructure of lipids significantly affects the three-dimensional network, ultimately determining their physical properties. Due to the unique physical properties of diacylglycerol (DAG), it can be effectively used as a functional substitute for traditional oil in plastic fats. This study explored the microstructure and physicochemical properties of high-purity sn-1,3 lauryl diacylglycerol (LDAG), palmityl diacylglycerol (PDAG), and their acyl migration equilibrium products (ME-DAG, sn-1,3 DAG: sn-1,2 DAG = 65:35) under different cooling rates. As the cooling rate increased, the hydrogen bond force and order degree of DAGs also rose. Sn-1,3 LDAG exhibited a larger lattice space, thicker nanoplatelet structure, and larger crystals than sn-1,3 PDAG at the micro-scale. The increasing cooling rate resulted in the transformation of β1 into unstable β2 forms in sn-1,3 DAGs. ME-PDAG demonstrated better resistance to β crystal growth at higher cooling rates, while ME-LDAG's crystal form remained unaffected by changes in cooling rate. ME-LDAG exhibited superior resistance to cooling rate compared to ME-PDAG. ME-DAG formed Maltese cross crystals after rapid cooling, potentially contributing to its hardness.
The process of lipid crystallization influences the characteristics of lipid. By changing the chemical composition of the lipid system, the crystallization behavior could be controlled. This review elucidates the internal factors affecting lipid crystallization, including triacylglycerol (TAG) structure, TAG composition, and minor components. The influence of these factors on the TAG crystal polymorphic form, nanostructure, microstructure, and physical properties is discussed. The interplay of these factors collectively influences crystallization across various scales. Variations in fatty acid chain length, double bonds, and branching, along with their arrangement on the glycerol backbone, dictate molecular interactions within and between TAG molecules. High-melting-point TAG dominates crystallization, while liquid oil hinders the process but facilitates polymorphic transitions. Unique molecular interactions arise from specific TAG combinations, yielding molecular compounds with distinctive properties. Nanoscale crystallization is significantly impacted by liquid oil and minor components. The interaction between the TAG and minor components determines the influence of minor components on the crystallization process. In addition, future perspectives on better design and control of lipid crystallization are also presented.
Diacylglycerol (DAG) is a novel functional structural lipid, but its application in base oils remains underexplored. This research investigated the effect of three liquid oils (groundnut oil, corn oil, and flaxseed oil), with varying polyunsaturated fatty acid (PUFA) (39.60, 69.50, and 77.65 %) and DAG content (0.00, 40.00, 80.00 %), on the crystallization behaviors of palm-based oil. DAG (40.00 %), obtained through enzymatic glycerolysis and molecular distillation, was found to stabilize the binary system with good compatibility and fine crystal structure. "Liquid" DAG played a dual role: diluting solid lipids, and promoting crystallization. Increasing DAG content led to larger crystalline domain size, while higher PUFA content accelerated crystallization and increased crystal orderliness, though decreasing crystal density. These results demonstrated the clear influence of PUFA and DAG content on palm-based oil crystallization. This knowledge can guide the utilization of different unsaturated DAGs for tailored fat crystallization in food application.
This research employed environmentally friendly dry fractionation to systematically modify the physicochemical properties of 80 % diacylglycerol derived from peanut oil (PDAG-80), expanding its potential food applications. The properties of olein and stearin were optimized by adjusting key parameters: crystallization temperatures (11, 13, 15 and 17 °C), cooling rates (2, 5, 8 and 11 °C/h), agitation speeds (10, 20, 30 and 40 rpm)and residence times (3, 6, 9 and 12 h). Lowering the crystallization temperature and extending the residence time increased the iodine value and solid fat content of olein. Additionally, diverse fractionation parameters yieled stearin with varying crystal ratios. The resulting olein fractionated from PDAG-80, a liquid at room temperature and rich in unsaturated fatty acids, exhibited superior cloudy property and oxidative stability. These findings not only deepen the understanding of PDAG-80 physical modification, but also provide a scientific foundation for developing high value-added PDAG products within the food industry.
The title compound, C(16)H(17)N(5)S, is in the thione form and crystallizes with two independent molecules in the asymmetric unit. In both molecules, the pentamethyleneimine five-membered ring adopts an envelope conformation, and in one of the molecules this ring shows positional disorder. The thione S and hydrazine N atoms are in the Z configuration with respect to the C-N bond.
Solution-mediated transformation has been cited as one of the main problems that deteriorate dissolution performances of solid dispersion (SD). This is mainly attributed by the recrystallization tendency of poorly soluble drug. Eventually, it will lead to extensive agglomeration which is a key process in reducing the dissolution performance of SD and offsets the true benefit of SD system. Here, a post-processing treatment is suggested in order to reduce the recrystallization tendency and hence bring forth the dissolution advantage of SD system.
This study aims to evaluate the effect of sucrose replacer mixtures (erythritol, mannitol, or tagatose in combination with inulin or polydextrose) on the crystal morphology, particle size distribution, rheology, melting properties, and fat polymorphism of dark compound chocolate. The result showed that the replacer mixture's hygroscopicity, particle size, and sugar crystal shape might significantly impact dark compound chocolate's rheological and textural properties but had no substantial impact on the melting properties and fat crystallization. Mannitol-containing samples exhibited the highest rheological value, likely related to their high moisture content, small particle size, and elongated crystal shape. Due to the similar specific surface area and comparable D90 value, the sample containing erythritol-polydextrose mixture resulted in a similar (P ≥ 0.05) Casson yield value (46.184 ± 2.45 Pa) compared to the sample containing sucrose (38.348 ± 1.68 Pa). It could be a potential sucrose replacer in the dark compound chocolate.
Seeding is a versatile method for optimizing crystal growth. Coupling this technique with capillary counter diffusion crystallization enhances the size and diffraction quality of the crystals. In this article, crystals for organic solvent-tolerant recombinant elastase strain K were successfully produced through microseeding with capillary counter-diffusion crystallization. This technique improved the nucleation success rate with a low protein concentration (3.00 mg/mL). The crystal was grown in 1 M ammonium phosphate monobasic and 0.1 M sodium citrate tribasic dihydrate pH 5.6. The optimized crystal size was 1 × 0.1 × 0.05 mm³. Elastase strain K successfully diffracted up to 1.39 Å at SPring-8, Japan, using synchrotron radiation for preliminary data diffraction analysis. The space group was determined to be monoclinic space group P12(1)1 with unit cell parameters of a = 38.99 Ǻ, b = 90.173 Å and c = 40.60 Å.
The binding of imidazolium salts to cucurbit[8]uril, CB[8], triggers a stepwise self-assembly process with semiflexible polymer chains and crystalline nanostructures as early- and late-stage species, respectively. In such a process, which involves the crystallization of the host-guest complexes, the guest plays a critical role in directing self-assembly toward desirable morphologies. These include platelet-like aggregates and two-dimensional (2D) fibers, which, moreover, exhibit viscoelastic and lyotropic properties. Our observations provide a deeper understanding of the self-assembly of CB[8] complexes, with fundamental implications in the design of functional 2D systems and crystalline materials.
The title compound, C16H10, crystallizes with four unique mol-ecules, designated 1-4, in the asymmetric unit of the monoclinic unit cell. None of the mol-ecules is planar, with the benzene rings of mol-ecules 1-4 inclined to one another at angles of 42.41 (4), 24.07 (6), 42.59 (4) and 46.88 (4)°, respectively. In the crystal, weak C-H⋯π(ring) interactions, augmented by even weaker C C-H⋯π(alkyne) contacts, generate a three-dimensional network structure with inter-linked columns of mol-ecules formed along the c-axis direction.
A new polymorphic form of the title compound, C8H8O3, is described in the centrosymmetric monoclinic space group P21/c with Z' = 1 as compared to the first polymorph, which crystallizes with two conformers (Z' = 2) in the asymmetric unit in the same space group. In the crystal of the second polymorph, inversion dimers linked by O-H⋯O hydrogen bonds occur and these are linked into zigzag chains, propagating along the b-axis direction by C-H⋯O links. The crystal structure also features a weak π-π inter-action, with a centroid-to-centroid distance of 3.8018 (6) Å. The second polymorph of the title compound is less stable than the reported first polymorph, as indicated by its smaller calculated lattice energy.
The title compounds, C14H12O, (I), and C15H11BrO2, (II), were prepared and characterized as part of our studies of potential new photo-acid generators. In (I), which crystallizes in the ortho-rhom-bic space group Pca21, compared to P21/n for the previously known monoclinic polymorph [Cornella & Martin (2013 ▸). Org. Lett. 15, 6298-6301], the dihedral angle between the aromatic rings is 4.35 (6)° and the OH group is disordered over two sites in a 0.795 (3):0.205 (3) ratio. In the crystal of (I), mol-ecules are linked by O-H⋯π inter-actions involving both the major and minor -OH disorder components, generating [001] chains as part of the herringbone packing motif. The asymmetric unit of (II) contains two mol-ecules with similar conformations (weighted r.m.s. overlay fit = 0.183 Å). In the crystal of (II), both mol-ecules form carboxyl-ate inversion dimers linked by pairs of O-H⋯O hydrogen bonds, generating R 2 (2)(8) loops in each case. The dimers are linked by pairs of C-H⋯O hydrogen bonds to form [010] chains.
Diacylglycerol at 1 or 6% was added into refined bleached and deodorized palm oil (RBDPO) and crystallized from the melt in a thermally controlled water bath at 22°C for 90 min. Slurries were withdrawn after 5, 15, 30, 60 and 90 min of crystallization for solid fat content (SFC) and crystal morphology studies. Crystallization was also performed in a similar manner using a Labmax reactor connected to a FBRM detector to obtain the information on crystal count and size distribution during crystallization. SFC of the slurries increased with increase in crystallization time up to a certain level followed by a plateau. SFC of RBDPO added with DAG was also higher with the increase in percentage of DAG added and no induction time was observed to initiate crystallization in RBDPO added with DAG. The addition of DAG caused rapid crystallization of RBDPO as observed by enhance nucleation and larger crystal size with increase in the percentages of DAG added.
Carbon nanotube reinforced aluminium matrix composites (Al-CNTs) have been widely used in aerospace and automotive industries where high quality and strength is required. The enhanced mechanical properties of Al-CNTs are closely related to processing technique due to challenges within production of these composite materials. In the current review, solid state processing techniques used for synthesizing Al-CNTs have been reviewed to provide an insight into the features and capabilities of each technique regarding the incorporation of CNT reinforcements. To conclude, the mechanical performance of Al-CNT composites is mainly decided by the capability of each technique in the dispersion of CNTs within the aluminum matrix.
Topological defect nucleation and boundary branching in crystal growth on a curved surface are two typical elastic instabilities driven by curvature induced stress, and have usually been discussed separately in the past. In this work they are simultaneously considered during crystal growth on a sphere. Phase diagrams with respect to sphere radius, size, edge energy and stiffness of the crystal for the equilibrium crystal morphologies are achieved by theoretical analysis and validated by Brownian dynamics simulations. The simulation results further demonstrate the detail of morphological evolution governed by these two different stress relaxation modes. Topological defect nucleation and boundary branching not only compete with each other but also coexist in a range of combinations of factors. Clarification of the interaction mechanism provides a better understanding of various curved crystal morphologies for their potential applications.
The effect of various multi-walled carbon nanotubes (MWNTs) on the tensile properties of thermoplastic natural rubber (TPNR) nanocomposite was investigated. The nanocomposite was prepared using melt blending method. MWNTs were added to improve the mechanical properties of MWNTs/TPNR composites in different compositions of 1, 3, 5, and 7 wt.%. The results showed that the mechanical properties of nanocomposites were affected significantly by the composition and the properties of MWNTs. SEM micrographs confirmed the homogenous dispersion of MWNTs in the TPNR matrix and promoted strong interfacial adhesion between MWNTs and the matrix which was improved mechanical properties significantly.
High internal phase emulsions (HIPEs) show promising application in food and cosmetic industries. In this work, diacylglycerol (DAG) was applied to fabricate water-in-oil (W/O) HIPEs. DAG-based emulsion can hold 60% water and the emulsion rigidity increased with water content, indicating the water droplets acted as "active fillers". Stable HIPE with 80% water fraction was formed through the combination of 6 wt% DAG with 1 wt% polyglycerol polyricinoleate (PGPR). The addition of 1 w% kappa (κ)-carrageenan and 0.5 M NaCl greatly reduced the droplet size and enhanced emulsion rigidity, and the interfacial tension of the internal phase was reduced. Benefiting from the Pickering crystals-stabilized interface by DAG as revealed by the microscopy and enhanced elastic modulus of emulsions with the gelation agents, the HIPEs demonstrated good retaining ability for anthocyanin and β-carotene. This study provides insights for the development of W/O HIPEs to fabricate low-calories margarines, spread or cosmetic creams.
Therapeutic peptides derived proteins with alpha-reconformation states like antibody shape have shown potential effects in combating terrible diseases linked with earlier signs of angiogensis, mutagenesis and transgenesis. Alpha reconformation in material design refers to the folding of the peptide chains and their transitions under reversible chemical bonds of disulfide chemical bridges and further non-covalence lesions. Thus, the rational design of signal peptides into alpha-helix is intended in increasing the defending effects of peptides into cores like adjuvant antibiotic and/or vaccines. Thereby, the signal peptides are able in displaying multiple eradicating regions by changing crystal-depositions and deviation angles. These types of molecular structures could have multiple advantages in tracing disease syndromes and impurities by increasing the host defense against the fates of pathogens and viruses, eventually leading to the loss in signaling by increasing peptide susceptibility levels to folding and unfolding and therefore, formation of transgenic peptide models. Alpha reconformation peptides is aimed in triggering as well as other regulatory functions such as remodulating metabolic chain disorders of lipolysis and glucolysis by increasing the insulin and leptin resistance for best lipid storages and lipoprotein density distributions.