Valorization of Proteins from Co- and By-Products from the Fish and Meat Industry.

Large volumes of protein-rich residual raw materials, such as heads, bones, carcasses, blood, skin, viscera, hooves and feathers, are created as a result of processing of animals from fisheries, aquaculture, livestock and poultry sectors. These residuals contain proteins and other essential nutrients with potentially bioactive properties, eligible for recycling and upgrading for higher-value products, e.g.

Extraction and physicochemical characterization of greater Lizardfish (Saurida tumbil) skin and bone gelatin.

Type A gelatins were extracted from skins and bones of lizardfish and analyzed to determine their functional and chemical properties. Lizardfish skin gelatin had ash content of 2.2 +/- 0.

Extraction and characterisation of gelatine from Atlantic salmon (Salmo salar) skin.

Gelatine was extracted from Atlantic salmon and Atlantic cod skin by the acid extraction process. After filtration and ion exchange treatment the extracts were colourless and free from fishy odour. In three separate experiments the average yields of gelatine from salmon and cod skins were 39.

Histone-like proteins from Atlantic cod milt: stimulatory effect on Atlantic salmon leucocytes in vivo and in vitro.

This study was carried out to reveal some characteristics of cationic proteins from Atlantic cod (Gadus morhua) milt chromatin and to investigate their ability to activate Atlantic salmon (Salmo salar) macrophages. Cationic proteins extracted from cod milt chromatin were fractionated on a cation exchange chromatography column. SDS-PAGE and amino acid analyses of the resulting fractions indicated that these proteins are similar to calf thymus histones.

Preparation and characterisation of gelatine from the skin of harp seal (Phoca groendlandica).

This paper describes a method for extraction of gelatine from the skin of harp seal at mild acid conditions and gives a chemical and physical comparison of this gelatine with other mammalian and cod-skin gelatines. As compared to the wet weight of unhaired skin, a recovery of 11% dry gelatine was achieved after acid treatment and a two step water extraction at 60 and 75 degrees C. The chemical and physical properties of the gelatine were similar to the properties of commercial gelatines made from bovine and porcine skin, but significantly different from the properties of Atlantic cod-skin gelatine.

HPLC preparation of fish waste hydrolysate fractions. Effect on guinea pig ileum and ACE activity.

The effect of RP-HPLC-purified fractions of fish waste hydrolysates issued from three fish industries was tested on guinea pig ileum in order to examine the presence of opioid molecules. The evaluation of anti-hypertensive activities of whole hydrolysates and fractions were also tested, monitoring the ability of the fraction to inhibit the activity of angiotensin I-converting enzyme involved in hypertension regulation. Sardine autolysate and cod head hydrolysate powder (50 microg) were able to inhibit near 30% of ACE activity, whereas 50 microg of shrimp hydrolysate allows the inhibition of 57% of ACE activity.

Utilisation of male Arctic capelin and Atlantic cod intestines for fish sauce production--evaluation of fermentation conditions.

The present paper shows that the fish by-products male Arctic capelin and Atlantic cod intestines can be utilized as raw materials for the production of high value fish sauce for human consumption. By supplementing minced capelin with 5-10% enzyme-rich cod pyloric caeca, a good recovery of fish sauce protein (60%) was obtained after 6 months of storage. Although, the proteases present in cod pylorus caeca are cold adapted enzymes, a storage temperature of 26 degrees C gave a higher fish sauce recovery than storage at 21 degrees C.

Secretagogues and Growth Factors in Fish and Crustacean Protein Hydrolysates.

: The search for new molecules in fish protein hydrolysates is of great interest in animal feeding as it is in aquaculture, fertilizer, cosmetic, and pharmacologic domains. Different sources of hydrolysates such as shrimp waste (Pandalus borealis), cod (Gadus morhua) head, and head and viscera of sardine (Sardina pilchardus), obtained after hydrolysis or autolysis, were tested on fibroblast cell cultures and by gastrin radioimmunoassay. The level of hydrolysis seems to play an important role in the presence of biological peptides.

Isolation of an acid fraction from a fish protein hydrolysate with a calcitonin-gene-related-peptide-like biological activity.

The possibility of obtaining calcitonin and/or calcitonin-gene-related peptide (CGRP) immunorelated molecules from partly digested proteins was investigated with fish and shrimp hydrolysates. These two peptides were quantified by both radioimmunoassay and radioreceptor assay; the positive extracts were partly purified. Different hydrolysates were analysed: cod head, stomach and viscera hydrolysates, a shrimp hydrolysate and two sardine hydrolysates.

Chitooligosaccharides stimulate Atlantic salmon, Salmo salar L., head kidney leukocytes to enhanced superoxide anion production in vitro.

Chitosans and chitooligosaccharides stimulated Atlantic salmon, Salmo salar L., head kidney leukocytes in vitro to produce elevated levels of superoxide anion. Both soluble and insoluble chitooligosaccharides were stimulatory 2 and 7 days after addition.

Human trophoblast interferons enhance major histocompatibility complex class I antigen expression on human term trophoblast cells in culture.

The expression and regulation of major histocompatibility complex class I (MHC class I) antigens by virus-induced human trophoblast interferons (tro-IFNs) were examined in term trophoblast cultures. Flow cytometry studies using fluorescence monoclonal antibodies against MHC class I antigens revealed that isolated cytotrophoblasts can express MHC class I antigens. The expression of these antigens increased with stimulation of trophoblast cultures with tro-IFN-alpha and -beta.

Differential interferon production in human first and third trimester trophoblast cultures stimulated with viruses.

Stimulation of human placental first and third trimester trophoblast and syncytiotrophoblast cultures with viruses [Newcastle Disease Virus (NDV) and Sendai virus] led to a high interferon (IFN) production. The magnitude of the production was dependent on the gestational age of the trophoblast, type of inducer and the stage of differentiation of the trophoblast. The data obtained indicated that the first trimester trophoblast cultures produced five to sixfold more IFN than the third trimester trophoblast on per cell basis whereas syncytiotrophoblast at term produced twice as much IFN than the mononuclear term trophoblast when stimulated with the viruses.

Catalytic properties and chemical composition of pepsins from Atlantic cod (Gadus morhua).

1. Three pepsins were purified from the gastric mucosa of Atlantic cod (Gadus morhua). 2.

Purification and characterization of pancreatic elastase from Atlantic cod (Gadus morhua).

1. A pancreatic elastase from Atlantic cod (Gadus morhua) has been purified and characterized. 2.

Aspartic proteinases in fishes and aquatic invertebrates.

1. The literature on molecular properties and physiological role of aspartic proteinases in fishes and aquatic invertebrates has been reviewed. 2.

Degradation of human epidermal keratin by fish pepsin.

Stomach extract of Atlantic herring Clupea harengus, Atlantic salmon Salmo salar, cod Gadus morhua, redfish Sebastes marinus, and plaice Pleuronectes platessa, degraded human epidermal keratin effectively in vitro. The keratin-degrading activity of all extracts showed a pH optimum around 3.3-3.

Preparation and testing of an autolysate of fish viscera as growth substrate for bacteria.

The aqueous soluble phase of acidified and autolyzed fish viscera was used as the nitrogen source in a growth medium for bacteria. The bacteria tested grew faster and produced higher yields of cell mass on this growth medium than on corresponding media with standard tryptone preparations as the nitrogen source.

Purification and characterization of pepsins from the arctic fish capelin (Mallotus villosus).

Two pepsins from the stomach of the arctic fish capelin (Mallotus villosus) have been isolated and characterized. The purification was achieved by ammonium sulphate precipitation, ion exchange chromatography and gel filtration. Both pepsins resemble mammalian pepsins regarding pepstatin sensitivity, amino acid composition, stability and specific activity.

Fish silage: a review.

Based on a review of various production principles of fish silage, this paper discusses the prospects of introduction of this method, as an alternative to fish meal, to utilize low value fish and waste products, particularly in developing countries. The paper covers the biochemistry, microbiology, and nutritional aspects of fish silage, as well as production technology and economy.