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Phospholipids play significant roles in numerous biological processes. They also have many applications in food, cosmetics, and pharmaceuticals. This article reviews the molecular structure, properties, and uses of these important lipids in food, beverages, and food supplements.

In school environments in the Sonoran Desert, dust contains anomalously high manganese (Mn) of geogenic origin, similar to those reported at industrial sites. Non-carcinogenic risk assessment for children exposed to Mn was estimated for two sampling seasons (pre-monsoon, post-monsoon). We determined the total Mn content in school dust samples by portable X-ray fluorescence (PXRF), and we used geochemical indices for Mn-source apportionment. We identified dust mineralogy by X-ray diffraction (XRD). We obtained the oral and lung bioaccessibility by in vitro tests. The results showed a much higher total Mn content (1725.7 mg·kg−1) in the

LDL, VLDL and other members of the low-density lipoparticles (LLPs) enter cells through a large family of receptors. The actual receptor ligand(s) in apolipoprotein B100, one of the main proteins of LLP, remain(s) unknown. The objective of this study was to identify true receptor ligand(s) in apo B100, a molecule of 4,563 residues. Apo B100 contains 33 analogues of Cardin-Weintraub Arginine/Lysine-based receptor ligand motifs and shares key Lysine motifs and sequence similarity with the LDL receptor-associated protein, RAP, MESD, and heat shock proteins. Eleven FITC-labeled synthetic peptides of 21 – 42 residues, with at least one ligand, were tested for binding and internalization using HeLa cells. All peptides bind but display different binding capacities and patterns. Peptides B0013, B0582, B2366, and B2932 mediate endocytosis and appear in distinct sites in the cytoplasm. B0708 and B3181 bind and remain on the cell surface as aggregates/clusters. Peptides B3119 (Site A) and B3347 (Site B), the putative ligands showed low binding and no cell entry capacity. Apo B100 regions in this study share similarities with related proteins of known function including chaperone proteins and Apo BEC Stimulating Protein, and not directly related proteins, e.g., the DNA-binding domain of Interferon Regulatory Factors, MSX2-Interacting Protein, and snake venom Zinc metalloproteinase-disintegrin-like proteins.

Specific structured lipids (SSL), previously produced by enzymatic acidolysis of coconut oil with different levels of conjugated linoleic acid (CLA) as fatty acid (FA), using a sn-1, 3 specific immobilized lipase, were used to prepare randomized structured lipids (RSL). A fraction of each SSL was subjected to chemical interesterification with sodium methoxide catalyst in order to modify the FA positional distribution and produce the corresponding RSL. Both families of structured lipids (SL) containing CLA were physicochemically characterized. Then, analysis of variance (ANOVA) was performed to evaluate the effects of CLA content (10, 20, 30 and 40%) and FA positional distribution (specific and randomized) on physicochemical properties of SL. Free fatty acids (FFA), peroxide value (PV) and p-anisidine value (p-AV) were not significantly affected by either CLA content or distribution. As expected, the iodine value (IV) and saponification value (SV) were influenced by CLA content but not by FA positional distribution, while oxidative stability index (OSI) was affected by both factors. Dropping point (DP), cloud point (CP) and solid fat content (SFC) decreased with the increase of CLA, while viscosity increased with the level of CLA. The FA positional distribution affected practically all the evaluated physical properties of SL, except CP and DP.

Structured phospholipids were synthesized with the functional lipid conjugated linoleic acid (CLA). The lipase- and phospholipase A 2 -catalyzed enzymatic acidolysis reaction between phospholipids (PL) and CLA was used for fatty acid modification. Enzymatic processes were an effective way to produce structured PL. Screening of four lipases and immobilized phospholipase A 2 and a combination of lipase and phospholipase showed that only Lipozyme RM IM and Lipozyme TL IM were effective in incorporation of CLA into PL. The maximum incorporation achieved by the latter enzyme was 16% with soy PL in 72 h.

As opposed to first-generation biotechnology products, such as pest-resistant crops and herbicide-resistant crops, second-generation products often utilize plant-derived, homologous or heterologous genes and/or promoters. In this study, we evaluated the ability of a promoter from a gene encoding a major storage protein in cottonseed to drive an antisense sequence of the cotton FAD2 gene to down-regulate the activity of Delta-12 desaturase enzyme in cottonseeds. The oleic acid level in the transgenic cottonseeds approximately doubled from the wild-type level of 15%, with a concomitant decrease in the level of linoleic acid. A more extensive study of one line revealed a higher degree of seed-to-seed variability in the transgenic phenotype. A thorough investigation was conducted to determine the impact of the use of a homologous promoter to drive a transgene on the activity of the endogenous promoter. The results showed that the use of the homologous alpha-globulin B promoter for transgenic purposes did not adversely affect the expression of alpha-globulin B storage protein in cottonseed. The results obtained in this investigation on the use of a homologous promoter and antisense technology will be useful in the design of strategies to alter biosynthetic pathways for nutritional quality improvements and for the production of heterologous proteins of commercial value in seeds.

Lipase-catalyzed acidolysis of different TAG with CLA was performed to produce structured lipids (SL) containing CLA. An immobilized lipase from Mucor miehei (Lipozyme IM, Novo Nordisk Inc., Franklinton, NC) was used as the biocatalyst in a solvent-free system. Conconut oil and tricaprylin, which are sources of medium-chain FA, were the starting substrates, and a mixture of FFA (MFFA) containing 73% CLA was the donor of the acyl groups. For each TAG, four different ratios of TAG/MFFA were blended to prepare about 500 g of mixture containing 10, 20, 30, and 40% CLA (w/w). Each blend was reacted with 5% lipase at 65°C for 48 h under nitrogen. Over the range of TAG/MFFA ratios examined, CLA was incorporated effectively by the enzyme. Lipozyme IM exhibited no special preference for any particular FA, since the incorporation of FA was proportional to their concentration in the system. FFA, PV, p-anisidine value (p-AV), iodine value (IV), and saponification number (SN) were evaluated for all the SL. FFA, PV, and p-AV depended on the purification process and showed no significant deterioration of SL with respect to the original TAG, whereas IV and SN depended on the composition of the SL, mainly the CLA content.

We report experimental results and a theoretical analysis of the Debye length in aqueous solutions of nonadsorbing polyelectrolytes. The measurements were done using a surface forces apparatus, in which the normal forces between smooth mica surfaces in aqueous hyaluronic acid (HA) solutions were measured as a function of surface separation (to ±1 A). HA is negatively charged and does not adsorb to the negatively charged surface of mica, as was established by optical and viscosity measurements and in agreement with the measured force−distance curves. From these measurements it appears that the multivalent polyelectrolyte is “depleted” from the gap between the surfaces. We use the mean-field Poisson−Boltzmann theory to theoretically predict the effective Debye length and double-layer force under such conditions and compare the predictions with the experimental results. The comparison gives excellent agreement and shows that the effective Debye length is determined solely by the monovalent ions in the soluti...

Cottonseed is a by-product of cotton fiber production. With each 100 pounds of fiber, the cotton plant produces approximately 165 pounds of cottonseed. However, it accounts for only 10 to 15% of the total value of a bale of cotton. Nearly 40% of cottonseed is fed directly to ruminant animals and the remainder is used as raw material for the cottonseed processing industry. Following oil extraction, the meal is mainly used as feed for cattle. Cottonseed is composed of ~ 22.5% of high nutritional quality protein. The amount of protein available annually from cottonseed worldwide is sufficient to meet the protein requirements of 350 million people (Lusas and Jividen, 1987). However, it can not be used to feed non-ruminant animals because of the presence of gossypol. Gossypol, a polyphenolic substance, is highly toxic to non-ruminant animals and is detrimental to human health if not removed from the oil. Thus, cottonseed represents a valuable resource that is grossly underutilized, principally due to the presence of gossypol. Elimination of gossypol from the seed will make the meal a valuable source of nutrition for monogastric animals as well as humans. However, this needs to be done in a highly seed-specific manner as gossypol and related terpenoids that are also present in the vegetative parts of the plant are believed to play a role in disease and insect resistance.

Freshly squeezed orange juice was ultrafiltered in a hollow fiber cross-flow ultrafiltration system. The suspended solids (pulp) in the juice were completely separated with a membrane cutoff of 5×10 5 molecular weight. The membrane retained most of the pectin material, and the viscosity of the permeate (juice serum) was appreciably reduced. Concentration of permeate by evaporation was achieved up to 75 o Brix. No pectinesterase activity was detected in the permeate. Some aroma compounds, particularly hydrocarbons, remained in the retentate

In the present study, plant sterols were modified to form amphiphiles by synthesizing phospholipid derivatives from them so they could be formulated in different functional foods and possibly improve their effects as therapeutic agents. The new phosphatidyl derivatives, phosphatidyl-sitosterols, were synthesized by the transfer reaction of a phosphatidyl residue from PC to beta-sitosterol by phospholipase D (PLD EC 3.1.4.4) from Streptomyces sp. in a biphasic medium.