New triterpenoid extractives from Lemaireocereus chichipe

1975 ◽  
Vol 28 (1) ◽  
pp. 165 ◽  
Author(s):  
PW Khong ◽  
KG Lewis
Keyword(s):  
Fatty Acids ◽  
Carbon Content ◽  
Hydrolysis Of ◽  
Triterpene Esters ◽  
Glycosidic Fraction

Reinvestigation of the glycosidic fraction of the extracts of the giant cactus Lemaireocereus chichipe has resulted in the isolation of a new triterpene triol to which is assigned the structure olean-12-ene- 3β,16β,22α-triol (5a). Two triterpene esters were also isolated, hydrolysis of which gave the known isomeric 3β,16β,28-triol longispinogenin (1a) and a mixture of even-carbon content fatty acids (C10-C18).

scholarly journals Enzymatic Methods for the Manipulation and Valorization of Soapstock from Vegetable Oil Refining Processes

2021 ◽  
Vol 2 (1) ◽  
pp. 74-91
Author(s):  
Beatrice Casali ◽  
Elisabetta Brenna ◽  
Fabio Parmeggiani ◽  
Davide Tessaro ◽  
Francesca Tentori
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Vegetable Oil ◽  
Lipase Production ◽  
Oil Refining ◽  
Flow Mode ◽  
Acid Oil ◽  
Industrial Level ◽  
Vegetable Oil Refining ◽  
Hydrolysis Of

The review will discuss the methods that have been optimized so far for the enzymatic hydrolysis of soapstock into enriched mixtures of free fatty acids, in order to offer a sustainable alternative to the procedure which is currently employed at the industrial level for converting soapstock into the by-product known as acid oil (or olein, i.e., free fatty acids removed from raw vegetable oil, dissolved in residual triglycerides). The further biocatalyzed manipulation of soapstock or of the corresponding acid oil for the production of biodiesel and fine chemicals (surfactants, plasticizers, and additives) will be described, with specific attention given to processes performed in continuous flow mode. The valorization of soapstock as carbon source in industrial lipase production will be also considered.

THE HYDROLYSIS OF MONOPHOSPHOINOSITIDE BY EXTRACTS OF BRAIN

1967 ◽  
Vol 45 (6) ◽  
pp. 853-861 ◽  
Author(s):  
W. Thompson
Keyword(s):  
Fatty Acids ◽  
Enzyme Activity ◽  
Calcium Ions ◽  
Brain Extract ◽  
Monovalent Cations ◽  
High Concentration ◽  
Diffusible Factor ◽  
Hydrolysis Of ◽  
The Brain ◽  
Long Chain

The hydrolysis of monophosphoinositide by soluble extracts from rat brain is described. Diglyceride and inositol monophosphate are liberated along with a small amount of free fatty acids. Hydrolysis of the lipid is optimal at pH 5.4 in acetate buffer. The reaction is stimulated by calcium ions or by high concentration of monovalent cations and, to a less extent, by long-chain cationic amphipathic compounds. Enzyme activity is lost on dialysis of the brain extract and can be restored by diffusible factor(s). Some differences in the conditions for hydrolysis of mono- and tri-phosphoinositides are noted.

scholarly journals Evidence for the regulation of guinea-pig heart microsomal phosphatidylcholine-hydrolysing phospholipase A1 by guanosine 5′-[γ-thio]triphosphate

1992 ◽  
Vol 288 (3) ◽  
pp. 965-968 ◽  
Author(s):  
K Badiani ◽  
X Lu ◽  
G Arthur
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Guinea Pig ◽  
Molecular Species ◽  
Inhibitory Effect ◽  
Phospholipase A1 ◽  
Guinea Pig Heart ◽  
Substrate Specificities ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of

We have recently characterized lysophospholipase A2 activities in guinea-pig heart microsomes and postulated that these enzymes act sequentially with phospholipases A1 to release fatty acids selectively from phosphatidylcholine (PC) and phosphatidylethanolamine, thus providing an alternative route to the phospholipase A2 mode of release. In a further investigation of the postulated pathway, we have characterized the PC-hydrolysing phospholipase A1 in guinea-pig heart microsomes. Our results show that the enzyme may have a preference for substrates with C16:0 over C18:0 at the sn-1 position. In addition, although the enzyme cleaves the sn-1 fatty acid, the rate of hydrolysis of PC substrates with C16:0 at the sn-1 position was influenced by the nature of the fatty acid at the sn-2 position. The order of decreasing preference was C18:2 > C20:4 = C18:1 > C16:0. The hydrolyses of the molecular species were differentially affected by heating at 60 degrees C. An investigation into the effect of nucleotides on the activity of the enzyme showed that guanosine 5′-[gamma-thio]triphosphate (GTP[S]) inhibited the hydrolysis of PC by phospholipase A1 activity, whereas GTP, guanosine 5′-[beta-thio]diphosphate (GDP[S]), GDP, ATP and adenosine 5′-[gamma-thio]triphosphate (ATP[S]) did not affect the activity. The inhibitory effect of GTP[S] on phospholipase A1 activity was blocked by preincubation with GDP[S]. A differential effect of GTP[S] on the hydrolysis of different molecular species was also observed. Taken together, the results of this study suggest the presence of more than one phospholipase A1 in the microsomes with different substrate specificities, which act sequentially with lysophospholipase A2 to release linoleic or arachidonic acid selectively from PC under resting conditions. Upon stimulation and activation of the G-protein, the release of fatty acids would be inhibited.

Rapid in vivo hydrolysis of fatty acid ethyl esters, toxic nonoxidative ethanol metabolites

1997 ◽  
Vol 273 (1) ◽  
pp. G184-G190 ◽  
Author(s):  
M. Saghir ◽  
J. Werner ◽  
M. Laposata
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Ethyl Esters ◽  
Ethyl Esters ◽  
Ethanol Ingestion ◽  
Gi Tract ◽  
Apparent Lack ◽  
Hydrolysis Of

Fatty acid ethyl esters (FAEE), esterification products of fatty acids and ethanol, are in use as fatty acid supplements, but they also have been implicated as toxic mediators of ethanol ingestion. We hypothesized that hydrolysis of orally ingested FAEE occurs in the gastrointestinal (GI) tract and in the blood to explain their apparent lack of toxicity. To study the in vivo inactivation of FAEE by hydrolysis to free fatty acids and ethanol, we assessed the hydrolysis of FAEE administered as an oil directly into the rat stomach and when injected within the core of low-density lipoprotein particles into the circulation of rats. Our studies demonstrate that FAEE are rapidly degraded to free fatty acids and ethanol in the GI tract at the level of the duodenum with limited hydrolysis in the stomach. In addition, FAEE are rapidly degraded in the circulation, with a half-life of only 58 s. Thus the degradation of FAEE in the GI tract and in the blood provides an explanation for the apparent lack of toxicity of orally ingested FAEE.

Lipids of the fin whale (Balaenoptera physalus) from North Atlantic waters. IV. Fin whale milk

1968 ◽  
Vol 46 (3) ◽  
pp. 197-203 ◽  
Author(s):  
R. G. Ackman ◽  
C. A. Eaton ◽  
S. N. Hooper
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Total Lipid ◽  
Iodine Value ◽  
North Atlantic ◽  
Methyl Esters ◽  
Short Chain Fatty Acids ◽  
Fin Whale ◽  
Hydrolysis Of

Fatty acid compositions were determined for total lipid (17.5% of the milk and > 95% triglycerides), 2-monoglyceride obtained by enzymatic hydrolysis of isolated triglyceride, and isolated phospholipid (~1% of total lipids). The total lipid fatty acids of the milk had a composition similar to fin whale depot fat but were enriched in hexadecanoic acid and polyunsaturated fatty acids at the expense of monoethylenic acids; correspondingly the iodine value of 136 (methyl esters) was higher than the normal range (105–120) of North Atlantic fin whale blubber oils. Over 80% of the fatty acids in the 2-position of the triglycerides were accounted for by relatively short chain fatty acids, especially hexadecanoic (54.6%), tetradecanoic (13.7%), and hexadecenoic (11.2%), so that the ester iodine value was only 48. The milk phospholipids had a fatty acid composition basically similar to that of liver phospholipids (methyl ester iodine value 120) with somewhat more polyunsaturated fatty acids and accordingly an iodine value of 144 for methyl esters.

scholarly journals Modulation of human type II secretory phospholipase A2 by sphingomyelin and annexin VI

1997 ◽  
Vol 326 (1) ◽  
pp. 227-233 ◽  
Author(s):  
Kamen KOUMANOV ◽  
Claude WOLF ◽  
Gilbert BÉREZIAT
Keyword(s):  
Fatty Acids ◽  
Polyunsaturated Fatty Acids ◽  
Phospholipase A2 ◽  
Cell Membranes ◽  
Red Cell ◽  
Type Ii ◽  
Membrane Phospholipids ◽  
Human Type ◽  
Annexin Vi ◽  
Hydrolysis Of

Conjectural results have been reported on the capacity of inflammatory secreted phospholipase A2 (sPLA2) to hydrolyse mammalian membrane phospholipids. Development of an assay based on the release of non-esterified fatty acids by the enzyme acting on the organized phospholipid mixture constituting the membrane matrix has led to the identification of two prominent effectors, sphingomyelin (SPH) and annexin. Recombinant human type II sPLA2 hydrolyses red-cell membrane phospholipids with a marked preference for the inner leaflet. This preference is apparently related to the high content of SPH in the outer leaflet, which inhibits sPLA2. This inhibition by SPH is specific for sPLA2. Cholesterol counteracts the inhibition of sPLA2 by SPH, suggesting that the SPH-to-cholesterol ratio accounts in vivo for the variable susceptibility of cell membranes to sPLA2. Different effects were observed of the presence of the non-hydrolysable D-α-dipalmitoyl phosphatidylcholine (D-DPPC), which renders the membranes rigid but does not inhibit sPLA2. Annexin VI was shown, along with other annexins, to inhibit sPLA2 activity by sequestering the phospholipid substrate. The present study has provided the first evidence that annexin VI, in concentrations that inhibit hydrolysis of purified phospholipid substrates, stimulated the hydrolysis of membrane phospholipids by sPLA2. The activation requires the presence of membrane proteins. The effect is specific for type II sPLA2 and is not reproducible with type I PLA2. The activation by annexin VI of sPLA2 acting on red cell membranes results in the preferential release of polyunsaturated fatty acids. It suggests that type II sPLA2, in conjunction with annexin VI, might be involved in the final step of endocytosis and/or exocytosis providing the free polyunsaturated fatty acids acting synergistically to cause membrane fusion.

Heparin-released lipolytic and esterolytic activities of human and rabbit plasmas

1961 ◽  
Vol 201 (5) ◽  
pp. 915-922 ◽  
Author(s):  
B. Shore ◽  
V. Shore
Keyword(s):  
Fatty Acids ◽  
Lipoprotein Lipase ◽  
Lipase Activity ◽  
Ethyl Esters ◽  
Lipoprotein Lipase Activity ◽  
Hydrolysis Of

The enzymes released into both human and rabbit plasmas by heparin injection hydrolyzed, in addition to triglyceride moieties of lipoproteins, a number of mono- and diglycerides of C16 and C18 fatty acids after in vitro addition of the unemulsified glycerides to the plasma. In human postheparin plasma, these enzymes also hydrolyzed glycerides of butyric and caproic acids. The pure triglycerides and methyl or ethyl esters of C16 and C18 fatty acids were not substrates. The heparin-released activities for the hydrolysis of glycerides added in vitro persisted after all activity for the lipolysis of lipoproteins had been destroyed by heat. These activities also differed from lipoprotein lipase activity with respect to the effects of 1 m NaCl, dialysis, and aging the plasma at 4 C. It appears that heparin releases into the blood more than one enzyme or more than one form of an enzyme which may be involved in a stepwise degradation to fatty acids and glycerol of the triglyceride moieties of lipoproteins of density less than 1.007 g/ml.

scholarly journals Characterization of the oils present in acid and fermented silages produced from Tilapia filleting residue

2011 ◽  
Vol 40 (2) ◽  
pp. 240-244 ◽  
Author(s):  
Rose Meire Vidotti ◽  
Maria Teresa Bertoldo Pacheco ◽  
Giovani Sampaio Gonçalves
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Nutritional Value ◽  
Lipid Fraction ◽  
Monounsaturated Fatty Acids ◽  
Degree Of Saturation ◽  
Degree Of Hydrolysis ◽  
Animal Feeding ◽  
Hydrolysis Of

The objective of this study was to determine the quality and composition of fatty acid in the lipid fraction of silages obtained from the residue of tilapia processing. Stratification of the lipid layer of the silages occurred at different times among the two types of silage (acid and fermented) and the greatest volume of oil was observed in acid silage (8.67% p/p). Although acid silage was more oxidized, it showed lower contents of free fatty acids probably because the degree of hydrolysis of its components is lower than that of fermented silage. Fatty acid composition did not differ among processes inasmuch as level of ϖ-3 was slightly higher in fermented silage. According to the degree of saturation, monounsaturated fatty acids stood out as the predominant category in acid and fermented silages with values of 39.69% and 33.39%, respectively. The use of antioxidants in the silage is needed because the process of production is carried out at temperatures higher than room temperature. The oil in the silages has excellent nutritional value and contains fatty acids essential for animal feeding.

Hydrolysis of rapeseed oil to fatty acids using pyrrolidonium ionic liquids as catalysts

2019 ◽  
Vol 41 (20) ◽  
pp. 2448-2459
Author(s):  
Benyong Han ◽  
Jinhe Jiang ◽  
Wudi Zhang ◽  
Fang Yin ◽  
Shiqing Liu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Ionic Liquids ◽  
Rapeseed Oil ◽  
Hydrolysis Of

scholarly journals Nutritional implications of l-arabinose in pigs

1992 ◽  
Vol 68 (1) ◽  
pp. 195-207 ◽  
Author(s):  
J. B. Schutte ◽  
J. de Jong ◽  
E. J. van Weerden ◽  
S. Tamminga
Keyword(s):  
Fatty Acids ◽  
Small Intestine ◽  
Lactic Acid ◽  
Urinary Excretion ◽  
Volatile Fatty Acids ◽  
Dietary Level ◽  
Ileal Digestibility ◽  
Dietary Nutrients ◽  
Pentose Sugar ◽  
Hydrolysis Of

The pentose sugar l-arabinose is one of the most abundant components released by complete hydrolysis of non-starch polysaccharides of feed ingredients of vegetable origin. Two studies were conducted to investigate the apparent ileal digestibility and urinary excretion of l-arabinose at dietary inclusion levels of 50 and 100 g/kg, and 25, 50, 75 and 100 g/kg respectively, in pigs. As a reference, d-glucose was included in the studies. Water intake, ileal flow of volatile fatty acids and ileal and faecal digestibilities of dietary nutrients in pigs fed on the different diets were also examined. Castrated pigs were prepared with a post-valvular T-caecum cannula to measure ileal digestibility. Faecal digestibility was measured in non-cannulated pigs. Apparent ileal digestibility of l-arabinose was found to be approximately 70%. The presence of l-arabinose in the diet increased ileal flow of volatile fatty acids and lactic acid, suggesting the occurrence of microbial degradation of l-arabinose in the pig small intestine. l-arabinose was partly excreted in the urine. The extent of this urinary excretion as a percentage of intake increased linearly (P < 0.01) as the dietary level increased. In pigs fed on the 25 g l-arabinose/kg diet, 10.9% of the l-arabinose consumed appeared in the urine. This level was increased to 14.7% when pigs were fed on a diet containing 100 g l-arabinose/kg diet. Faecal digestibility and retention of nitrogen decreased significantly in pigs fed on the l-arabinose diets.

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