Phospholipase A Activity in Rainbow Trout Muscle

1967 ◽  
Vol 24 (12) ◽  
pp. 2555-2562 ◽  
Author(s):  
R. E. E. Jonas ◽  
E. Bilinski
Keyword(s):  
Rainbow Trout ◽  
Lateral Line ◽  
Silicic Acid Column ◽  
Fish Muscle ◽  
Enzymic Activity ◽  
Phospholipase A ◽  
Experimental Conditions ◽  
Optimum Ph ◽  
Layer Chromatography ◽  
Trout Muscle

A sensitive method for assay of phospholipase A activity in the lateral line muscle of rainbow trout is described. 14C labelled lecithin was converted to lysolecithin by the enzyme. Unreacted lecithin was removed by silicic acid column chromatography and the lysolecithin recovered by thin-layer chromatography. The amount of lysolecithin formed was between 43 and 87 mμmoles per gram lateral line muscle per hour under the experimental conditions. The amount formed was directly proportional to time between half an hour and 4 hr and the optimum pH was found to be approximately 7.5. The results are discussed in relation to the enzymic activity previously demonstrated in fish muscle.

Glycerylphosphorylcholine and Related Compounds in Rainbow Trout Muscle Stored at −4 C

1967 ◽  
Vol 24 (2) ◽  
pp. 273-280 ◽  
Author(s):  
R. E. E. Jonas ◽  
E. Bilinski
Keyword(s):  
Fatty Acids ◽  
Rainbow Trout ◽  
General Trend ◽  
Fish Muscle ◽  
Enzymic Activity ◽  
Salmo Gairdneri ◽  
Threefold Increase ◽  
Free Choline ◽  
Related Compounds ◽  
Trout Muscle

Glycerylphosphorylcholine in rainbow trout (Salmo gairdneri) muscle stored at −4 C showed an increase from 36 μmoles/100 g in fresh muscle to 46 μmoles/100 g after 2 weeks. During longer periods of storage an approximately threefold increase in concentration took place, reaching 123 and 105 μmoles/100 g muscle after 9 and 17 weeks. Liberation of free choline was found to take place after 6 weeks of storage. There was very little change in the concentration of choline after 6 weeks storage when the value was approximately 100 μmoles/100 g. The release of free fatty acid during cold storage showed a general trend, which was similar to the formation of glycerylphosphorylcholine, but quantitatively the changes were more pronounced. Free fatty acids amounted to 45 μmoles/100 g in fresh muscle and rose to a plateau of approximately 1200 μmoles/100 g after 9 weeks of storage. The results are discussed in relation to the enzymic activity present in fish muscle.

Lecithinase Activity in the Muscle of Rainbow Trout (Salmo gairdnerii)

1966 ◽  
Vol 23 (2) ◽  
pp. 207-220 ◽  
Author(s):  
E. Bilinski ◽  
R. E. E. Jonas
Keyword(s):  
Rainbow Trout ◽  
Lateral Line ◽  
White Muscle ◽  
Radioactive Tracer ◽  
Enzymic Activity ◽  
The Other ◽  
Level Of Activity ◽  
Hydrolysis Of ◽  
Trout Muscle

A radioactive tracer procedure for determination of the various lecithin hydrolysing enzymes, at a low level of activity, is described. The procedure involves the use of phospholipids labeled with C14in the choline moiety as substrate and the measurement of radioactivity released in the various products of hydrolysis. The pathway of lecithin catabolism in trout muscle is via glycerylphosphorylcholine. Of the other possible routes of breakdown of lecithin, there was no indication for the activity of phospholipase C or D. Greater enzymic activity was present in the lateral line muscle than in the white muscle. The enzyme which is responsible for hydrolysis of lecithin to glycerylphosphorylcholine showed optimum activity in the vicinity of pH 7 did not require Ca++for activity and was partially inhibited by Hg++. A lysolecithinase, showing similar properties, but having a comparatively greater activity, was also present in trout muscle.

PROPERTIES OF THE PHOSPHOLIPASE B FROM PENICILLIUM NOTATUM

1967 ◽  
Vol 45 (1) ◽  
pp. 101-113 ◽  
Author(s):  
Joyce L. Beare ◽  
Morris Kates
Keyword(s):  
Enzymic Activity ◽  
Water Soluble ◽  
Soluble Phosphate ◽  
Enzymic Hydrolysis ◽  
Ferric Ions ◽  
Penicillium Notatum ◽  
Degree Of Unsaturation ◽  
Phospholipase B ◽  
Optimum Ph ◽  
Layer Chromatography

Phospholipase B from Penicillium notatum catalyzed rapid deacylation of purified egg lecithin, in the absence of any activators, when the substrate was ultrasonically dispersed. The rate of enzymic hydrolysis depended on the degree of dispersion of the substrate and also on its degree of unsaturation. Decrease in acyl ester groups was accompanied by release of water-soluble phosphate identified as glycerylphosphorylcholine; no lysolecithin was detected by thin-layer chromatography at any stage of the reaction. The optimum pH in acetate buffer was 4.0, and the apparent Kmwas 6.3 mM for the ultrasonically dispersed substrate. The enzyme attacked lysolecithin more rapidly than lecithin. Enzymic activity was not affected by iodoacetate, cyanide, or cystine, but was strongly inhibited by glutathione, cysteine, thioglycollate, ferrous and ferric ions, or by prolonged dialysis. Inhibition by glutathione was completely reversed by ferricyanide. These results suggest that the enzyme requires —S—S— linkages for activity.

Tissue damage in organic rainbow trout muscle investigated by proteomics and bioinformatics

PROTEOMICS ◽  
2013 ◽  
Vol 13 (14) ◽  
pp. 2180-2190
Author(s):  
Tune Wulff ◽  
Tomé Silva ◽  
Michael Engelbrecht Nielsen
Keyword(s):  
Rainbow Trout ◽  
Tissue Damage ◽  
Trout Muscle

A PROTEOLYTIC PSEUDOMONAD FROM SKIN LESIONS OF RAINBOW TROUT (SALMO GAIRDNERII): I. CHARACTERISTICS OF THE PATHOGENIC EFFECTS AND THE EXTRACELLULAR PROTEINASE

1967 ◽  
Vol 13 (4) ◽  
pp. 405-416 ◽  
Author(s):  
M. F. Li ◽  
Carol Flemming
Keyword(s):  
Rainbow Trout ◽  
Subcutaneous Injection ◽  
Skin Lesions ◽  
Muscular Tissue ◽  
Fluorescent Pseudomonad ◽  
Extracellular Proteinase ◽  
Bacterial Proteinase ◽  
High Degree ◽  
Trout Muscle ◽  
Live Organism

A fluorescent pseudomonad producing a powerful extracellular proteinase and closely resembling but not identical with Pseudomonas fluorescens was isolated from skin lesions of rainbow trout. Subcutaneous injection of the live organism into healthy frogs caused a condition typical of redleg disease, followed by death, and its subcutaneous injection into healthy rainbow trout caused the formation of large, necrotic, swollen areas filled with fluid. The organism was re-isolated from the deliberately infected animals and histological examinations showed a high degree of destruction of the muscular tissue in the affected areas. The pathogenic effect observed was apparently due to the extracellular bacterial proteinase. Growth of the pseudomonad was insignificant at 3 °C and 37 °C, was slight at 8 °C, and optimal between 15 and 25 °C, and the culture filtrates possessed strong proteolytic activity against casein, hemoglobin, and rainbow trout muscle albumin. The production of this proteinase was dependent on the growth of the organism and the composition of the growth medium.

Comparison of Different Methods for the Determination of Phenylalanine Hydroxylase Activity in Rat Liver and Euglena gracilis

1984 ◽  
Vol 39 (7-8) ◽  
pp. 728-733 ◽  
Author(s):  
Rita M. Fink ◽  
Erich F. Elstner
Keyword(s):  
Rat Liver ◽  
Euglena Gracilis ◽  
Phenylalanine Hydroxylase ◽  
Hplc Method ◽  
Enzymic Activity ◽  
Hydroxylase Activity ◽  
Product Separation ◽  
Tyrosine Concentration ◽  
Layer Chromatography

Abstract Three different methods for the determination of phenylalanine hydroxylase activity have been compared: a) Differential photometric assay of the increase in tyrosine concentration in the presence of phenylalanine; b) Product separation by thin layer chromatography and scintillation counting of the [14C]tyrosine formed;c) HPLC separation and spectrofluorometric quantification of derivatized amino acids. A comparison of the activities of phenylalanine hydroxylase in rat liver and Euglena gracilis clearly showed that only rat liver contains this enzymic activity as shown by methods b) and c) although pseudo-activity of Euglena gracilis preparations was found during the spectrophotometric test a). The HPLC method proved to be the fastest, most reliable and convenient method for direct tyrosine determination and thus for measuring phenylalanine hydroxylase activity.

scholarly journals Effect of temperature on acid hydrolysis of Jerusalem artichoke as raw material for ethanol production

2013 ◽  
pp. 279-287 ◽  
Author(s):  
Radojka Razmovski ◽  
Vesna Vucurovic ◽  
Uros Miljic ◽  
Vladimir Puskas
Keyword(s):  
Hold Time ◽  
Jerusalem Artichoke ◽  
Raw Material ◽  
Effect Of Temperature ◽  
Industrial Biotechnology ◽  
Microbial Conversion ◽  
Experimental Conditions ◽  
Theoretical Yield ◽  
Renewable Raw Material ◽  
Layer Chromatography

Jerusalem artichoke (JA) is a low-requirement crop, which does not interfere with food chain, and is a promising carbon source for industrial fermentation. Microbial conversion of such a renewable raw material to useful products, such as ethanol, is an important objective in industrial biotechnology. In this study, ethanol was efficiently produced from the hydrolyzates of JA obtained at different pH values (pH 2.5, pH 3.0 and pH 3.5), temperature (120, 130, 132 and 134?C) and hold time (30 and 60 min) by Saccharomyces cerevisiae. The efficient degradation of JA by HCl under certain experimental conditions was confirmed by thin-layer chromatography. Ethanol concentration of 7.52% (w/w), which corresponds to 93.89 % of the theoretical yield is achieved by ethanol fermentation of JA hydrolyzate obtained at pH 2.5.

Dissolution of Fish Muscle Homogenates by Lysolecithin

1968 ◽  
Vol 25 (10) ◽  
pp. 2157-2164
Author(s):  
R. E. E. Jonas
Keyword(s):  
Skeletal Muscle ◽  
Rainbow Trout ◽  
Snake Venom ◽  
Incubation Medium ◽  
Fish Muscle ◽  
N Content ◽  
Snake Venom Phospholipase ◽  
Solubilizing Activity ◽  
Supernatant Solution ◽  
Muscle Homogenate

On incubating skeletal muscle homogenates from rainbow trout with lysolecithin (LL) and comparing them with homogenates of the same muscle without added LL, and after centrifuging the mixtures, it was found that the N content of the supernatant solution of the homogenate containing LL was about 20% higher than that of the homogenate without LL. Increases close to maximum in N content of the supernatant solution were found to occur at a concentration of about 4 mg LL per ml of incubation medium containing 100 mg muscle in 3.0 ml of 0.9% NaCl at a pH of 6.0–8.0 and at about 35 C for a period of 1 hr. Snake venom phospholipase A added to muscle homogenate showed no solubilizing activity and α-tocopherol acetate and cortisol showed irregular stimulation. It was concluded that LL exerts a solubilizing action on fish muscle homogenates.

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