Carp Scales Research Articles

DIFFERENT THERMOSTABILITY OF COLLAGENS FROM SCALE OF CARP (CYPRINUS CARPIO) IN WINTER AND SUMMER

The acid-soluble collagens (ASC) were isolated from scale of carp (Cyprinus carpio) caught in the winter and summer. Thermal denaturing behaviors of collagens were investigated by the increased pepsin digestibility and by changes in circular dichroism (CD) spectrum upon heating. The denaturation temperature of collagen were estimated from the half decrease of b component upon heating and subsequent pepsin digestion. Collagen from scales in the winter (w-scale ASC) exhibited a transition curve with a midpoint of 31.6C, which was 1.8C below that of scale collagen from the summer fish (s-scale ASC). The CD measurement results showed the melting temperature of s-scale ASC was higher than that of w-scale ASC by 3C. It was concluded s-scale ASC was more stable than the equivalent from the winter season. The research offered the fundamental information on the carp scale collagens that may be utilized in the food, cosmetic and pharmaceutical industries.

Possibilities of LA-ICP-MS technique for the spatial elemental analysis of the recent fish scales: Line scan vs. depth profiling

LA-ICP-MS and solution based ICP-MS in combination with electron microprobe are presented as a method for the determination of the elemental spatial distribution in fish scales which represent an example of a heterogeneous layered bone structure. Two different LA-ICP-MS techniques were tested on recent common carp ( Cyprinus carpio) scales: (a) A line scan through the whole fish scale perpendicular to the growth rings. The ablation crater of 55 μm width and 50 μm depth allowed analysis of the elemental distribution in the external layer. Suitable ablation conditions providing a deeper ablation crater gave average values from the external HAP layer and the collagen basal plate. (b) Depth profiling using spot analysis was tested in fish scales for the first time. Spot analysis allows information to be obtained about the depth profile of the elements at the selected position on the sample. The combination of all mentioned laser ablation techniques provides complete information about the elemental distribution in the fish scale samples. The results were compared with the solution based ICP-MS and EMP analyses. The fact that the results of depth profiling are in a good agreement both with EMP and PIXE results and, with the assumed ways of incorporation of the studied elements in the HAP structure, suggests a very good potential for this method.

Effect of EDTA, HCl, and Citric Acid on Ca Salt Removal from Asian (Silver) Carp Scales Prior to Gelatin Extraction

Pretreatments with different chemicals at different concentrations to remove Ca compounds were studied to determine their effects on gelatin extraction from silver carp (Hypophthalmichthys molitrix) scales. During Ca removal with HCl, citric acid, and EDTA, all 3 chemicals were able to decalcify (>90%) scales; however, protein losses with EDTA were lower than with HCl and citric acid (P < 0.05), and protein losses with citric acid were lower than with HCl (P < 0.05). Ca removal with HCl yielded a solution where 4% to 5% of the protein was Hyp, with estimated gelatin losses from 0.9% to 2.5%. After 0.20 mol/L HCl was used for Ca removal, the extracted gelatin solution was 15.4% of the initial scales weight and gave a gel strength of 128 g. After using 1.2 g/L citric acid for Ca removal, the extracted gelatin solution was only 9% of the scales and the gel strength was 97 g. Using 0.20 mol/L EDTA for Ca removal gave a yield of 22% and a gel strength of 152 g. These data suggest that EDTA at 0.20 mol/L provides the best Ca removal with minimal collagen/gelatin removal (estimated gelatin loss was less than 0.013%) during the Ca removal step, and subsequently gave a high gelatin yield and gel strength. Fish gelatin has generally been extracted from fish skins and occasionally fish bones. This article focuses on removing the Ca compounds in fish scales and then producing fish gelatin with a good gel strength and yield. With further studies, this study may help the fish industry to have a new source of fish gelatin for food and pharmaceutical applications.

Preparation and thermal stability of collagen from scales of grass carp (Ctenopharyngodon idellus)

Grass carp (Ctenopharyngodon idellus) scales (GCS) was swollen in water and treated with microwave for 2 min, followed by decalcifying with 8% aqueous citric acid solution. The collagen of GCS was then prepared by limited pepsin digestion with a yield of 25.64% on dry weight basis. SDS-PAGE, FT-IR and amino acid composition analysis indicated that the pepsin-solubilized collagen from GCS was typical type I collagen, consisting of three different α chains, α1, α2 and α3. The thermal stability of pepsin-solubilized collagen from GCS was studied using viscometry, circular dichroism (CD) and Raman spectroscopies. The denaturation temperature (Td) of collagen solution was 32 °C determined by viscometry. CD spectra analysis showed that the Td of GCS solution was between 35 °C and 40 °C, and further confirmed by Raman spectra. Thus, a large amount of collagen could be obtained from GCS and the preparation method is safe and time-economizing, and GCS will have potential as an important collagen source for use in various industries.

Precision of Scales and Dorsal Spines for Estimating Age of Common Carp

ABSTRACT We examined precision in age estimates from common carp (Cyprinus carpio) scales and dorsal spines sampled from 28 Iowa lakes (N = 501 individual fish). Exact agreement between two readers was 28.5% for scales and 90.6% for dorsal spines. Agreement of scale ages between readers was poor across the distribution of assigned ages. Agreement of dorsal spine ages increased to 95.8% after a joint examination conducted to assess reasons for disagreements. Age estimates from scales were as much as eight years less and seven years greater than ages estimated from dorsal spines, and discrepancies occurred in young as well as old fish.

Structural Aspects of the Calcification Process of Lower Vertebrate Collagen

In order to investigate the structural relationship between inorganic phase and collagen fibrils in the calcified tissues of lower vertebrates we have carried out a wide and small angle X-ray diffraction investigation on carp scales and bone samples.The small angle patterns from decalcified bone and scales, as well as uncalcified tendon samples from carp are very similar to that of type I collagen from higher vertebrates. The D-axial period, 67 nm, is the same as that of higher vertebrate type I collagen, while the most significant difference is the relatively low intensity of the first order reflection, which is, however, the most intense.The relative intensity distributions of the meridional reflections recorded from fish bone and scales are in agreement with an electron density distribution according to a step function. The calculated step length is very close to the values previously reported for calcified tissues from higher vertebrates. The small angle reflections from calcified, as well as decalcified, scales display different directions of orientation, which could be in agreement with a plywood arrangement of collagen fibrils in successive sheets parallel to the plane of the scale.

Site-specific lead distribution in scales of lead-administered carp ( Cyprinus carpio) by non-destructive SR-XRF analysis

By utilizing non-destructive synchrotron radiation-excited X-ray fluorescence (SR-XRF), we observed the distribution of lead (Pb) in both ontogenic and regenerating scales of lead-administrated carp, Cyprinus carpio. The fish in the Pb-administered group were fed pellets containing 1 mg/g of Pb at a rate of 1.5% body weight per day for 30 days. In the ontogenic scales, Pb was highly accumulated near the basal edge of the scale and the accumulated amount decreased toward the focus of the scale. On the other hand, in the regenerating scales, high accumulation was observed near the basal edge and the accumulated amount remained high toward the focus. The present results of Pb accumulation correspond well with the region which is calcifying in the ontogenic and regenerating scales, and indicate that the distributions of Pb show when and how long Pb was administered.

Changes in the Distributions of Chemical Elements in Regenerating Scales of Carp, Cyprinus carpio, Studied by SRXRF Imaging

Two-dimensional distributions of calcium, phosphorus, strontium, and zinc in regenerating scales of carp, Cyprinus carpio, were observed over a period of 90 days by utilizing synchrotron radiation-excited X-ray fluorescence (SRXRF) imaging. On the 15th day, these elements were highly accumulated in the part that is exposed to the ambient water, and the accumulated amount decreased linearly toward the basal edge through the focal area of the scale. As the regeneration progressed, this characteristic pattern changed such that the amount of each element in the rim part, which was exposed to the ambient water, obviously increased, while the amount in the basal edge decreased. However, the relative amounts of phosphorus, strontium, and zinc with respect to calcium in the regenerating scale remained almost constant during the regeneration. In addition, it was found that the diameter of, and the number of ridges in, the regenerating scales increased rapidly during the first 15 days, and increased at a slower pace later on.

Un couvercle de sarcophage paléochrétien, vestige de la dévotion à saint Jean-Baptiste à l'abbaye de Saint-Denis

At the Maison d'Education de la Légion d'Honneur at Saint-Denis is a palaeochristian lid of a sarcophagus which has not been previously studied. It has been reused to cover an ossuary housing the bones of Bénédictine monks, exhumed during work on the cloister in the eighteenth Century and reburied in September 1886 in the cemetery of the Maison, next to the park. The slab is eut prismatically in the form of a roof with four slopes, three of which are sculpted with round imbrications in the form of carp scales. It differs from other similarly sculpted lids dating from the early Middle Ages with respect to its material : a very hard pink and white veined marble, and with respect to an engraved inscription referring to the décollation of Saint John the Baptist, yet another witness to the ancient and often attested cuit of the Baptist at the abbey of Saint Denis.

Binding sites for melanin-concentrating hormone (MCH) in brain synaptosomes and membranes from peripheral tissues identified with highly tritiated MCH.

Melanin-concentrating hormone (MCH) is a neuropeptide occurring in the brain of all vertebrate species. In chromatophores of teleost fishes it induces pigment granule aggregation. In mammals, however, its physiological function is not yet clear. Attempts to identify the site(s) of its action by binding analysis failed because radioiodinated MCH with the natural sequence was devoid of biological activity. We have now synthesized an analogue of rat/human MCH, [Pra4,8,12,19]-MCH, containing four L-propargylglycine (Pra) residues in positions 4, 8, 12, and 19 for catalytic tritiation to norvaline ([3H4]Nva) residues, each of which containing four tritium atoms. The resulting [3H]-MCH ([(3H4)Nva4,8,12,19]-MCH) had a specific radioactivity of approx. 12,200 GBq/mmol (330 Ci/mmol) and retained a biological activity of 10% as compared to rat/human MCH when tested in the carp scale assay. A series of qualitative binding studies performed with rat crude membranes from brain and peripheal tissues as well as with rat brain synaptosomes using the [3H]-MCH radioligand provided the first evidence for the presence of MCH receptors in mammalian tissues. The data showed that specific binding is present in the hypothalamus, hippocampus and in the adrenal gland while none was detected in the brain cortex or spleen. Owing to the tendency of [3H]-MCH to non-specific binding to tissue, glass and plastic surfaces, a saturation binding analysis with this radioligand was not possible.

Application of electron paramagnetic resonance (EPR) spectroscopy for control of irradiated food

AbstractFour groups of foodstuffs were irradiated in a 60Co source with doses from 0.3 to 10kGy and subsequently measured by EPR spectrometry at room temperature in air: (1) poultry bones and fins, scales and bones of carp. (2) seeds of selected fruits, (3) dehydrated mushrooms, and (4) a selected set of spices and herbs. Qualitative and, in some cases, quantitative data related to the absorbed dose of radiation were collected. In the irradiated bones from poultry and carp an asymmetric singlet (gI = 2.0030, gII =1.9973; ΔHpp = 0.85 mT) was detected which was stable at room temperature and was similar to that previously found in irradiated mammalian bones. Another stable EPR signal (g0 = 2.0024, ΔHpp = 0.56 mT) was found in the fins and scales of carp which was about five times more intense in fins than in scales. In pips of pears irradiated with a dose of 3 kGy. a signal which was about twice as intense as the endogenous signal was recorded. A multicomponent EPR signal derived from the stones of dates differed from the endogenous signal even when a low dose (0‐5 kGy) was applied. A multicomponent EPR signal is also observed in dried mushrooms irradiated with a dose of 3 kGy. In white mustard, paprika and chilli no native EPR signal exists and a radiation‐induced stable EPR signal can still be observed after a period of 3 months. The radiation‐induced EPR signal in black pepper was highly sensitive to moisture and disappeared, yet the native signal survived. The pilot experiments performed with irradiated stones of cherries, plums, lemons, apple pips, raspberries, cranberries, red currants, blackcurrants, gooseberries and tomatoes showed the induction of short‐lived EPR signals of no practical use for the control of food irradiation.

Structure-activity studies with fragments and analogues of salmonid melanin-concentrating hormone

A number of cyclic and linear fragments and analogues of MCH were synthesized and their biological potencies tested using the isolated carp scale melanophore assay. In this system, the cyclic portion MCH(5–14) exhibited only 0.1% bioactivity, which was markedly enhanced by the addition of the exocyclic sequences MCH(15–17) and MCH(1–4). The exocyclic sequence itself, MCH(1–4, 15–17), had minimal activity, however. Substitution of Tyr 11 with phenylalanine reduced the potency of the ring structure MCH(5–14) by about 4-fold. Substitution of Gly 8 with D-alanine reduced the potency of MCH(5–14) 16-fold, while both substitutions together caused a still more marked reduction (200-fold) in bioactivity. Linearized fragments of MCH, extending from MCH(15–17) to [Cys(Acm) 5,14]MCH(1–17), showed a progressive increase in potency. The linearized forms of MCH, MCH(5–17) and MCH(5–14), were approximately 100-fold or less potent than their cyclic forms. The significant increases in bioactivity produced by the addition of the C- and N-terminal exocyclic sequence even to these linearized forms further emphasizes the importance of these regions for interaction at the receptor site.