LPCS

LPC Processes. Process development for LPC production dates from the United Kingdom and Hungary from 1920—1940 (89,90). Table 9 presents some of the processing methods that are used or under development in the 1990s. 

Solvent extraction removes chlorophyll and other pigments to give a light-colored product but increases processing costs. Furthermore, solvent extraction removes p-carotene and reduces vitamin A activity (89) (see Terpenoids Vitamins). Supercritical CO2 extraction at 30 and 70 MPa (4,350 and 10,150 psi) and 40°C removed 90 and 70% carotene and lutein, respectively, from alfalfa LPC (96). This process avoids organic solvent residues and recovers valuable by-products. 

Leaf materials also contain Hpoxidases and highly unsaturated Hpids. LPC process conditions should inactivate Hpoxidases to obtain a stable product... 

LPC Product Quality. Table 10 gives approximate analyses of several LPC products. Amino acid analyses of LPC products have been pubhshed including those from alfalfa, wheat leaf, barley, and lupin (101) soybean, sugar beet, and tobacco (102) Pro-Xan LPC products (100,103) and for a variety of other crop plants (104,105). The composition of LPCs varies widely depending on the raw materials and processes used. Amino acid profiles are generally satisfactory except for low sulfur amino acid contents, ie, cystine and methionine. 

Table 11 presents data on the protein quaUty of a variety of LPC products obtained from rat-feeding studies. Typical protein efficiency ratio (PER) values for LPCs derived from alfalfa range from 1.41 without supplementation to 2.57 with 0.4% methionine added casein can be adjusted to a PER of 2.50 (98,100). Biological values (BV) of mixtures of LPCs, such as barley and rye grass or soybean and alfalfa, maybe higher than either LPC alone. The effect has been attributed to the enhanced biological availabihty of lysine in these mixtures (99). 

The 1993 market for LPC-type products in the United States was for dried alfalfa meal for animal feed. This product is sold for both protein and carotenoid content. The USDA Pro-Xan product attempts to obtain improved xanthophyU contents for use in egg-laying rations in addition to protein contents. The limitations to commercial development of LPC products for human food use are high capital costs as compared with the low yields of protein, seasonal availabihty of raw materials, and the need in the United States for FDA approval of the products. 

The total phosphoms content of the sample is determined by method AOCS Ja 5-55. Analysis of phosphoUpid in lecithin concentrates (AOCS Ja 7-86) is performed by fractionation with two-dimensional thin-layer chromatography (tic) followed by acid digestion and reaction with molybdate to measure total phosphorous for each fraction at 310 nm. It is a semiquantitative method for PC, PE, PI, PA, LPC, and LPE. Method AOCS Ja 7b-91 is for the direct deterrnination of single phosphoHpids PE, PA, PI, PC in lecithin by high performance Hquid chromatography (hplc). The method is appHcable to oil-containing lecithins, deoiled lecithins, lecithin fractions, but not appHcable to lyso-PC and lyso-PE. 

Total quantity LPC store Size of largest stack Minimum separation distance to boundary, building or fixed ignition sources from tbe nearest cylinder (where no fire wall provided) Minimum separation distance to boundary, building or fixed ignition source from fire wall (where provided) ... 

Liquefied petroleum gas Storage of LPC at Eixed Installations (HSE, HSG 34) Storage and Use of LPC at Metered Estates (HSE, CSll) Storage and Use of LPC on Construction Sites (HSE, CS6) Keeping of LPC in Cylinders and Similar Containers (HSE, CS4)... 

GPR4 SPC, LPC Migration, angiogenesis, impairment of endothelial barrier function... 

Maury, F., Oquab, D., Morancho, R., Nowak, J., and Gauthier, J., Low Temperature Deposition of Chromium Carbide by LPC VD Process using Bis-Arene Chromium as Single Source, Croc. 10th Int. Conf. on CVD, (G. Cullen, ed.), pp. 1213-1219, Electrochem Soc., Pennington, NJ 08534 (1987)... 

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