Lipolytic activity

In their study of untrained vs. trained swimmers, Collomp et al.40 suggested that specific training may be the catalyst that stimulates caffeine s ergogenic effects during high intensity, anaerobic activity. The results of many studies have also suggested that only well-trained athletes derive significant benefits from caffeine due to the athletes previously stimulated lipolytic activity and the increased size and density of their mito-chondria.40-52-58-59... 

Long ago it was noticed that the baking quality of white flour improved with storage for 1-2 months. This effect occurred more rapidly if the flour was exposed to the air. During storage, initially the level of free fatty acids increases, presumably owing to lipolytic activity. Lipoxygenase activity then produces oxidised fatty acids as the proportion of linoleic and linolenic acids falls while the number of -S-S- bonds decreases. 

In any of these cases lipolytic activity can shorten the shelf life of the product or render it totally unacceptable. 

Specihc poly anions such as dextran sulfate (DS) appear to exhibit strong anti-HIV activity in vitro [36,37]. Human oral administration of DS is poorly absorbed, but intravaneous administration does result in increased plasma lipolytic activity [38]. Poly anions that have been considered for intravaginal anti-HIV activity include DS, carrageenan, heparin, heparan sulfate, dermatan sulfate, pentosan polysulfate, fucoidan chondroitin sulfate, keratan sulfate, and PAVAS [21,22,39,40],... 

Yoshikawa M, Shimoda H, Nishida N, Takada M, Matsuda H. (2002) Salacia reticulata and its polyphenolic constituents with lipase inhibitory and lipolytic activities have mild antiobesity effects in rats. J Nutr 132 1819-1824. 

Pectase was found in plants, both in soluble and non soluble form. It was able to break down pectose into pectinic acid, and was attributed some similarity to diastase. Neither materials could be crystallized (Payen, 1874). Claude Bernard was the first to show lipolytic activity in pancreas in 1856 (Tauber, 1949), and Dobell (1869) found that an extract from pancreas hydrolyzed both fat and starch he gave a procedure for extraction and stabilization and named this preparation pancreatine . 

Chitin and chitosan derivatives have also been studied as blood compatible materials both in vivo and in vitro [520], Anticoagulant activity was greatest with O sulfated N acetyl chitosan, followed by N,0 sulfated chitosan, heparin, and finally sulfated N acetyl chitosan. The lipolytic activity was greatest for N,0 sulfated chitosan followed by heparin. The generally poor performance of chitosan was attributed to polyelectrolyte complexes with free amino groups present on the membrane surface. The O sulfate or acidic group at the 6 position in the hexosamine moiety was identified as the main active site for anticoagulant activity. 

Exocrine pancreatic insufficiency is most commonly caused by cystic fibrosis, chronic pancreatitis, or pancreatic resection. When secretion of pancreatic enzymes falls below 10% of normal, fat and protein digestion is impaired and can lead to steatorrhea, azotorrhea, vitamin malabsorption, and weight loss. Pancreatic enzyme supplements, which contain a mixture of amylase, lipase, and proteases, are the mainstay of treatment for pancreatic enzyme insufficiency. Two major types of preparations in use are pancreatin and pancrelipase. Pancreatin is an alcohol-derived extract of hog pancreas with relatively low concentrations of lipase and proteolytic enzymes, whereas pancrelipase is an enriched preparation. On a per-weight basis, pancrelipase has approximately 12 times the lipolytic activity and more than 4 times the proteolytic activity of pancreatin. Consequently, pancreatin is no longer in common clinical use. Only pancrelipase is discussed here. 

A good-quality rennet extract is free of lipolytic activity but a rennet paste is used in the manufacture of some Italian varieties, e.g. Romano and Provolone. Rennet paste contains a lipase, referred to as pre-gastric esterase (PGE), which makes a major contribution to lipolysis in, and to the characteristic flavour of, these cheeses. Rennet paste is considered unhygienic and therefore semi-purified PGE may be added to rennet extract for such cheeses (Chapter 8). 

Lipolysis. Some lipolysis occurs in all cheeses the resulting fatty acids contribute to cheese flavour. In most varieties, lipolysis is rather limited (Table 10.5) and is caused mainly by the limited lipolytic activity of the starter and non-starter lactic acid bacteria, perhaps with a contribution from indigenous milk lipase, especially in cheese made from raw milk. 

While the batch process is the dominant one in current use, researchers and companies have attempted to create continuous bioreactor systems. Lopez et al. immobilized Candida rugosa in polymethacrylamide hydrazide beads and polyurethane foam 3 with the intent to achieve the continuous production of lipase enzymes. Despite flow problems with the polyurethane foam, it showed high lipolytic activity. Biomass buildup was problematic. Feijoo et al. immobilized Phanerochaete chry-sosporium on polyurethane foam in packed bed bioreactors under near-plug flow conditions. Continuous lignin peroxidase production was accomplished, the rate of which was studied as a function of recycle ratio. 

Bovine blood serum is lipolytically active, but cows producing milk which goes rancid quickly do not have sera that are more lipolytically active than those producing normal milk. Leukocytes, which are present in large numbers in milk, are especially high in mastitic milk they are the source of milk catalase but are apparently not the source of milk lipases (Nelson and Jezeski 1955). 

The freezing of raw milk followed by thawing to 4°C causes an increase in lipolysis compared to that of unfrozen control milk stored at 4°C, but the increase in activity varies considerably. Repeated freezing and thawing also causes a notable increase in lipolytic activity. The temperature of freezing has a marked effect, the increase in lipolysis being most pronounced when the temperature is lowered from —10 to... 

Bjorke, K. and Castberg, H. B. 1976. Lipolytic activity in goat s milk. Nord. Mejeri-Tidsskift 8, 296-304. 

Frankel, E. N. and Tarassuk, N. P. 1956A. The specificity of milk lipase. I. Determination of the lipolytic activity in milk toward milk fat and simpler esters. J. Dairy Sci. 39, 1506-1516. 

Gholson, J. H., Schexnailder, R. H. and Rusoff, L. L. 1966B. Influence of a poor-quality low-energy ration on lipolytic activity in milk. J. Dairy Sci. 49, 1136-1139. 

Kelly, P. L. 1943. The lipolytic activity of bovine mammary gland tissue. J. Dairy Sci. 26, 385-399. 

Manus, L. J. and Bendixen, H. A. 1956. Effects of lipolytic activity and of mercuric chloride on the Babcock test for fat in composite milk samples. J. Dairy Sci. 39 508-513. 

Menger, J. W. 1975. Experience with lipolytic activities in milk and dairy products. Int. Dairy Fed. Doc. 86, pp. 108-112. 

Nilsson, R. and Will art, S. 1960. Lipolytic activity in milk. II. The heat inactivation of fat splitting in milk. Milk Dairy Res., Alnarp. Sweden, Rep. 64,... 

Willart, S. and Sjostrom, G. 1962. Pasteurization of milk and its effect on the lipolytic activity measured at different pH values. Ind. Dairy Congr. A, 669-674. 

Fryer, T. F., Reiter, B. and Lawrence, R. C. 1967. Lipolytic activity of lactic acid bacteria. 

Ruban, E. L., Lobyreva, L. B., Sviridenko, Y. Y., Marchenkova, A. I. and Umanskii, M. S. 1978. Lipolytic activity of microorganisms isolated from different sources. AppL Biochem. Microbiol. 14, 393-396. 

Rhizopus arrhizus (ATCC 24563) is a filamentous fungus, known to be producer of an exocellular lipase. According to the culture medium and especially to the carbon and nitrogen sources the lipolytic activity can remain bound to the cells. 

High-dose glucocorticoid therapy can cause marked hypertriglyceridemia, with milky plasma (SEDA-15, 421 SEDA-16, 450). It has been suggested that this is caused by abnormal accumulation of dietary fat, reduced postheparin lipolytic activity, and glucose intolerance (126). An association between glucocorticoid exposure and hypercholesterolemia has been found in several studies (127) and can contribute to an increased risk of atherosclerotic vascular disease. 

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