The Effects of Different Carotenoid Sources on Skin Pigmentation of Goldfish (Carassius auratus)

The aim of this study was to investigate the effect of different carotenoid sources on goldfish (Carassius auratus) skin pigmentation. The value of goldfish depends on the intensity of the skin color. In the red variety of goldfish, an orange-red hue is desirable. Juvenile goldfish were fed one of five diets for five months to determine the effects of carotenoids on skin pigmentation, growth, feed efficiency, and survival: (1) astaxanthin (carophyll pink at 75 mg/kg), (2) canthaxanthin (carophyll red at 75 mg/kg), (3) Gammarus spp. (75 mg/kg), (4) Oleoresin paprika (180 mg/kg), and (5) an unsupplemented control. Growth and feed efficiency did not significantly differ among groups. Initial and final samples of head skin were measured by colorimetric analysis for lightness (L*), redness (a*), yellowness (b*), hue (Hºab), and chroma (Cab*). The best red color (a* and Hºab) was obtained with the astaxanthin, canthaxanthin, and paprika diets

The Paleogene Ophiolite Conundrum of the Iran-Iraq Border Region

New and compiled geochemical, isotopic and geochronological data allow us to propose a new explanation for Paleogene oceanicmagmatic rocks alongtheIran–Iraqborder.These rocks are represented byathick pile(>1000 m) ofpillow lavas and pelagic sediments and underlying plutonic rocks. These are sometimes argued to represent a Paleogene ophiolite but there are no associated mantle rocks. Integrated zircon U–Pb ages, bulk rock major and trace element and radiogenic isotope data indicate that these rocks are more likely related to forearc rifting due to extreme extension during Late Paleogene time whichalsotriggeredhigh-fluxmagmatismintheUrumieh–DokhtarMagmaticBeltandexhumationofcorecomplexesinIran. These observations are most consistent with formation of the Paleogene oceanic igneous rocks in a >220 km long forearc rift zone

Zircon U-Pb, geochemical and isotopic constraints on the age and origin of A- and I-type granites and gabbro-diorites from NW Iran

Highlights • There are Late Cretaceous granitoids and Paleocene A-type granites in NW Iran. • Different mechanisms are suggested for genesis of granitoids and A-type granites. • Subduction initiation and extension generated granitoids during the Late Cretaceous. Abstract The continental crust of NW Iran is intruded by Late Cretaceous I-type granites and gabbro-diorites as well as Paleocene A-type granites. SIMS and LA-ICPMS U-Pb analyses of zircons yield ages of 100–92 Ma (Late Cretaceous) for I-type granites and gabbro-diorites and 61–63 Ma (Paleocene) for A-type granites. Late Cretaceous gabbro-diorites (including mafic microgranular enclaves; MMEs) from NW Iran show variably evolved signatures. They show depletion in Nb and Ta on N-MORB-normalized trace-element spider-diagrams and have high Th/Yb ratios, suggesting their precursor magmas were generated in a subduction-related environment. Gabbro-diorites have variable zircon εHf(t) values of +1.2 to +8, δ18O of 6.4 to 7.4‰ and bulk rock εNd(t) of −1.4 to ~ +4.9. The geochemical and isotopic data attest to melting of subcontinental lithospheric mantle (SCLM) to generate near-primitive gabbros with radiogenic Nd isotopes (εNd(t) = ~ +4.9) and high Nb/Ta and Zr/Hf ratios, similar to mantle melts (Nb/Ta ~ 17 and Zr/Hf ~ 38). These mafic melts underwent further fractionation and mixing with crustal melts to generate Late Cretaceous evolved gabbro-diorites. Geochemical data for I-type granites indicate both Nb-Ta negative and positive anomalies along with enrichment in light REEs. These rocks are peraluminous and have variable bulk-rock εNd(t) (−1.4 to +1.3), zircon εHf(t) (+2.8 to +10.4) and δ18O (4.7–7.3‰) values, but radiogenic bulk rock Pb isotopes. The geochemical and isotopic signatures of these granites suggest interaction of mantle-derived mafic magmas (similar to near-primitive Oshnavieh gabbros) with middle-upper crust through assimilation-fractional crystallization (AFC) to produce Late Cretaceous I-type granites. Paleocene A-type granites have distinctive geochemical features compared to I-type granitoids, including enrichment in Nb-Ta, high bulk rock εNd(t) (+3.3 to +3.9) and zircon εHf(t) (+5.1 − +9.9) values. Alkaline granites are ferroan; they have low MgO, CaO, Sr, Ba and Eu concentrations and high total Fe2O3, K2O, Na2O, Al2O3, Ga, Zr, Nb-Ta, Th and rare earth element (REE) abundances and Ga/Al ratios. These rocks might be related to fractionation of a melt derived from a sub-continental lithospheric mantle, but which interacted with asthenosphere-derived melts. We suggest that subduction initiation and the resultant slab roll-back caused extreme extension in the overlying Iranian plate, induced convection in the mantle wedge and led to the decompression melting of SCLM. Rising mantle-derived magmas assimilated middle-upper crustal rocks. Fractionating mantle-derived magmas and contamination with crustal components produced evolved gabbro-diorites and I-type granites. In contrast, asthenospheric upwelling during the Paleocene provided heat for melting and interaction with SCLM to generate the precursor melts to the A-type granites

Relative contributions of crust and mantle to generation of Campanian high-K calc-alkaline I-type granitoids in a subduction setting, with special reference to the Harsit Pluton, Eastern Turkey

We present elemental and Sr-Nd-Pb isotopic data for the magmatic suite (similar to 79 Ma) of the Harsit pluton, from the Eastern Pontides (NE Turkey), with the aim of determining its magma source and geodynamic evolution. The pluton comprises granite, granodiorite, tonalite and minor diorite (SiO(2) = 59.43-76.95 wt%), with only minor gabbroic diorite mafic microgranular enclaves in composition (SiO(2) = 54.95-56.32 wt%), and exhibits low Mg# (<46). All samples show a high-K calc-alkaline differentiation trend and I-type features. The chondrite-normalized REE patterns are fractionated [(La/Yb)(n) = 2.40-12.44] and display weak Eu anomalies (Eu/Eu* = 0.30-0.76). The rocks are characterized by enrichment of LILE and depletion of HFSE. The Harsit host rocks have weak concave-upward REE patterns, suggesting that amphibole and garnet played a significant role in their generation during magma segregation. The host rocks and their enclaves are isotopically indistinguishable. Sr-Nd isotopic data for all of the samples display I(Sr) = 0.70676-0.70708, epsilon(Nd)(79 Ma) = -4.4 to -3.3, with T(DM) = 1.09-1.36 Ga. The lead isotopic ratios are ((206)Pb/(204)pb) = 18.79-18.87, ((207)Pb/(204)Pb) = 15.59-15.61 and ((208)Pb/(204)Pb) = 38.71-38.83. These geochemical data rule out pure crustal-derived magma genesis in a post-collision extensional stage and suggest mixed-origin magma generation in a subduction setting. The melting that generated these high-K granitoidic rocks may have resulted from the upper Cretaceous subduction of the Izmir-Ankara-Erzincan oceanic slab beneath the Eurasian block in the region. The back-arc extensional events would have caused melting of the enriched subcontinental lithospheric mantle and formed mafic magma. The underplating of the lower crust by mafic magmas would have played a significant role in the generation of high-K magma. Thus, a thermal anomaly induced by underplated basic magma into a hot crust would have caused partial melting in the lower part of the crust. In this scenario, the lithospheric mantle-derived basaltic melt first mixed with granitic magma of crustal origin at depth. Then, the melts, which subsequently underwent a fractional crystallization and crustal assimilation processes, could ascend to shallower crustal levels to generate a variety of rock types ranging from diorite to granite. Sr-Nd isotope modeling shows that the generation of these magmas involved similar to 65-75% of the lower crustal-derived melt and similar to 25-35% of subcontinental lithospheric mantle. Further, geochemical data and the Ar-Ar plateau age on hornblende, combined with regional studies, imply that the Harsit pluton formed in a subduction setting and that the back-arc extensional period started by least similar to 79 Ma in the Eastern Pontides.Geochemistry & GeophysicsMineralogySCI(E)33ARTICLE4467-48716

Zircon Lu-Hf isotope systematics and U-Pb geochronology, whole-rock Sr-Nd isotopes and geochemistry of the early Jurassic Gokcedere pluton, Sakarya Zone-NE Turkey: a magmatic response to roll-back of the Paleo-Tethyan oceanic lithosphere

KANDEMIR, RAIF/0000-0002-0344-9159WOS: 000403544100007The early Mesozoic was a critical era for the geodynamic evolution of the Sakarya Zone as transition from accretion to collision events in the region. However, its complex evolutionary history is still debated. To address this issue, we present new in situ zircon U-Pb ages and Lu-Hf isotope data, whole-rock Sr-Nd isotopes, and mineral chemistry and geochemistry data of plutonic rocks to better understand the magmatic processes. the Gokcedere pluton is mainly composed of gabbro and gabbroic diorite. LA-ICP-MS zircon U-Pb dating reveals that the pluton was emplaced in the early Jurassic (177 Ma). These gabbros and gabbroic diorites are characterized by relatively low SiO2 content of 47.09 to 57.15 wt% and high Mg# values varying from 46 to 75. the samples belong to the calc-alkaline series and exhibit a metaluminous I-type character. Moreover, they are slightly enriched in large ion lithophile elements (Rb, Ba, Th and K) and light rare earth elements and depleted in high field strength elements (Nb and Ti). Gabbroic rocks of the pluton have a depleted Sr-Nd isotopic composition, including low initial Sr-87/Sr-86 ranging from 0.705124 to 0.705599, relatively high epsilon(Nd) (t) values varying from 0.1 to 3.5 and single-stage Nd model ages (T-DM1 = 0.65-0.95 Ga). in situ zircon analyses show that the rocks have variable and positive epsilon(Hf) (t) values (4.6 to 13.5) and single-stage Hf model ages (T-DM1 = 0.30 to 0.65 Ga). Both the geochemical signature and Sr-Nd-Hf isotopic composition of the gabbroic rocks reveal that the magma of the studied rocks was formed by the partial melting of a depleted mantle wedge metasomatized by slab-derived fluids. the influence of slab fluids is mirrored by their trace-element characteristics. Trace-element modeling suggests that the primary magma was generated by a low and variable degree of partial melting (similar to 5-15%) of a depleted and young lithospheric mantle wedge consisting of phlogopite-and spinel-bearing lherzolite. Heat to melt the mantle material was supplied by the ascendance of a hot asthenosphere triggered by the roll-back of the Paleo-Tethyan oceanic lithosphere. the rising melts were accompanied by fractional crystallization and encountered no or minor crustal contamination en route to the surface. Taking into account these geochemical data and integrating them with regional geological evidence, we propose a slab roll-back model; this model suggests that the Gokcedere gabbroic pluton originated in a back-arc extensional environment associated with the southward subduction of the Paleo-Tethyan oceanic lithosphere during the early Jurassic period. Such an extensional event led to the opening of the northern branch of the Neotethys as a back-arc basin. Consequently, we conclude that the gabbroic pluton was related to intensive extensional tectonic events, which peaked during the early Jurassic in response to the roll-back of Paleo-Tethyan oceanic slab in the final stage of oceanic closure.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112Y103]This research was financially supported by Grant # 112Y103 from the Scientific and Technological Research Council of Turkey (TUBITAK). Faruk Aydin, Ibrahim Uysal, Yilmaz Demir and Mehdi Ilhan are thanked for their assistance in field and lab works. We would like to thank to E. Yalcin Ersoy for the geo-chemical modeling of the trace-element data. We gratefully acknowledge on English editing efforts of the manuscript by Jacqueline O'Neill Ozcelik. Special thanks to three anonymous reviewers whose comments improved this paper significantly. Further thanks are owed to Gordon Moore for his editorial effort and constructive comments

Postcollisional transition from subduction- to intraplate-type magmatism in the eastern Sakarya zone, Turkey: Indicators of northern Neotethyan slab breakoff

WOS: 000483604100012Postcollisional magmatism in the eastern Sakarya zone was recorded by voluminous basic volcanism and repeated plutonism during the early Cenozoic. the temporal and geochemical evolution of these magmatic rocks is important for understanding the possible geodynamic history of the Sakarya zone. Here, we investigated three representative plutons lying between the towns of Camlihemsin (Rize) and Ispir (Erzurum), Turkey. These are largely composed of medium-K gabbroic diorites (Marselavat Pluton), shoshonitic monzonites (Gullubag Pluton), and high-K granites (Ayder Pluton). We present whole-rock geochemistry, Ar-40/Ar-39 geochronology, and Sr, Nd, and Pb isotope analyses from the plutons to constrain the timing of variations in magmatism and source characteristics, and we provide a new approach to the proposed geodynamic models, which are still heavily debated. the Ar-40/Ar-39 geochronology reveals a cooling sequence from ca. 45 Ma for the Marselavat Pluton through ca. 41 Ma for the Giilliibag Pluton to ca. 40 Ma for the Ayder Pluton. Whole-rock geochemistry and Sr, Nd, Pb isotopes suggest that crustal contamination was not an important factor affecting magma compositions. Although there was no arc-related tectonic setting in the region during the middle Eocene, the Marselavat Pluton shows some subduction affinities, such as moderately negative Nb and Ta anomalies, and slightly positive Pb anomalies. These signatures were possibly inherited from a depleted mantle source that was modified by hydrous fluids released from the oceanic slab during Late Cretaceous subduction. Geochemical traces of the earlier subduction become uncertain in the Gullubag samples. They display ocean-island basalt-like multi-element profiles and Nb/Ta, Ce/Pb, and La/Ba ratios. All these point to a mantle source in which earlier subduction signatures were hybridized by the addition of asthenospheric melts. Melting of calc-alkaline crustal material, probably emplaced during the first phase of middle Eocene magmatism (Marselavat), led to the formation of granitic plutonism (Ayder Pluton). Our data in conjunction with early Eocene adakite-like rocks show that melt generation, as in the given sequence, was most probably triggered by breakoff of the northern Neotethyan oceanic slab, similar to 13 m.y. after the early Maastrichtian collision between the Sakarya zone and Anatolide-Tauride block, and continued until the end of the middle Eocene. A shallow-marine transgression occurred contemporaneously with the middle Eocene magmatism throughout the Sakarya zone. An extension in this magnitude seems unlikely to be the result of orogenic collapse processes only. the main cause of this extension was most probably related to the northward subduction of the southern Neotethys Ocean beneath the Anatolide-Tauride block. the result is a volumetrically larger amount of middle Eocene magmatism than that expected in response to slab breakoff.Karadeniz Technical University (BAP Project)Karadeniz Technical University [2007.118.002.2]; Karadeniz Technical UniversityKaradeniz Technical University [FBA-2015-5314]A. Dokuz acknowledges financial support through a grant from Karadeniz Technical University (BAP Project no. 2007.118.002.2) awarded to A. Dokuz, and also benefited from another grant (BAP Project no. FBA-2015-5314) from Karadeniz Technical University awarded to F. Aydin. Frank C. Ramos (New Mexico State University) conducted Sr, Nd, and Pb isotope analyses, and Robert Duncan (Oregon State University) assisted with 40Ar/39Ar ages. We are very grateful to Aral Okay and Yann Rolland for their extremely careful and constructive reviews, which improved the quality of the paper significantly. We thank Associate Editor Erdin Bozkurt and Editor-in-Chief Brad S. Singer for their insightful editorial comments and suggestions. Caner Akyel is also thanked for his assistance during the fieldwork

Petrogenesis of the Neogene alkaline volcanics with implications for post-collisional lithospheric thinning of the Eastern Pontides, NE Turkey

WOS: 000259667400016Whole-rock geochemistry, Sr-Nd-Pb isotopes and K-Ar data are reported for alkaline samples collected from the Neogene alkaline volcanics (NAVs) in the Eastern Pontides, northeastern Turkey, in order to investigate their source and petrogenesis and geodynamic evaluation of the region. The NAVs were made of three groups that comprise of basanite-tephrite (feldspar-free; Group A), tephrite-tephriphonolite (feldspar and feldspathoid-bearing; Group B) and alkaline basalt-rhyolite (feldspathoid-free, Group C) series. These rocks cover a broad compositional range from silica-undersaturated to silica-oversaturated types, almost all of which are potassic in character. They show enrichment of LREE and LILE and depletion of HFSE, without a Eu anomaly in most of the mafic, samples. Textural features and calculated pressures based on the Cpx-barometer in each series indicate that the alkaline magma equilibrated at shallow crustal depths under a pressure of about 3-4.5 kbar and approximating a crystallization depth of 9-14 km. The NAVs are slightly depleted in isotopic composition, with respect to Sr-87/Sr-86 (ranging from 0.705018 to 0.705643) and Nd-143/Nd-144 (ranging from 0.512662 to 0.512714) that indicate young Nd model ages (0.51-059 Ga). This may indicate that the parent melts tapped a homogeneous and young lithospheric mantle source which was metasomatized by subduction-derived sediments during the Late Mesozoic. Pb isotopic compositions (Pb-206/Pb-204=18.85-18.95; Pb-207/Pb-204=15.60-15.74; Pb-208/Pb-204=38.82-39.25) may also be consistent with a model for an enriched subcontinental lithospheric mantle source. Lithospheric thinning and resultant upwelling of asthenosphere induced by lithospheric delamination may have favoured partial melting of chemically enriched, Young lithospheric mantle beneath the Eastern Pontides. Then, the melt subsequently underwent a fractional crystallization process along with or without minor amounts of crustal assimilation, generating a wide variety of rock types in a post-collision extensional regime in the Eastern Pontides during the Neogene. (C) 2008 Elsevier B.V. All rights reserved.Research Foundation of Karadeniz Technical University from Trabzon, NE-Turkey; DAADThis work was partly supported by the Research Foundation of Karadeniz Technical University from Trabzon, NE-Turkey. Sincere thanks are due to the DAAD for scholarship to Faruk Aydin. We thank Rainer Altherr and Hans-Peter Meyer in providing the microprobe analyses at Mineralogy and Petrology Institute, Heidelberg. We are grateful to M. Burhan Sadiklar for logistic support. Many thanks are given to Ismet Gedik and Abdurrahman Dokuz for their comments on the geodynamic modeling of this study. Raif Kandemir is thanked for his never-ending assistance during some figure designs. Special thanks are due to G. Pe-Piper and M.F.J. Flower for their useful suggestions and comments which considerably improved the manuscript. O. Cakir edited the English of the final text. Editorial comments by N. Eby are also acknowledged

Compositional Variations, Zoning Types and Petrogenetic Implications of Low-pressure Clinopyroxenes in the Neogene Alkaline Volcanic Rocks of Northeastern Turkey

WOS: 000266902800001Clinopyroxene phenocrysts and microphenocrysts in different series of the Neogene alkaline volcanic rocks from the eastern Pontides (NE Turkey) record various stages in the crystallization conditions and evolution history of the alkaline melt as well as its origin. Crystal chemical studies reveal that the clinopyroxenes in each rock series show strong textural and compositional similarities, which all reflect a common petrogenetic affinity. They have relatively high Mg-numbers (0.68-0.95), variable Al(2)O(3) (1.3-9.6 wt%), low TiO(2) (<2.7 wt%) and Na(2)O (<0.9 wt%) contents and low Al([6])/Al([4]) ratios (mostly <0.25), suggesting relatively low-pressure crystallization conditions of the magma in the storage region. The pressures calculated for the clinopyroxenes in each series are nearly similar and vary in the range of 2.4-4.6 +/- 0.9 kbars, which approximately corresponds to a crystallization depth of 714 +/- 3 km. The analyses of the compositional trends of the clinopyroxenes indicate the following types of zoning: (i) oscillatory and sectorial zoning related to melt crystallization (i.e. rapid cooling and crystallization), (ii) oscillatory, reverse zoning related to the different crystallization paths under a variable fluid regime, (iii) normal zoning related to the differentiation and fractional crystallization of the magma. Based on the primitive mantle- and chondrite-normalized trace and rare earth element patterns, all clinopyroxenes have high abundances of incompatible elements (i.e. La, Ce) with negative high field strength element anomalies (i.e. Zr, Ti) and low Nb/Y (0.1-0.2), Th/Y (<0.1) and Rb/Y (<0.03) ratios, suggesting derivation from a similar source. Obtained textural and mineral chemical data, as well as whole-rock compositions, thus suggest that the clinopyroxenes may have started to crystallize from alkaline basaltic magma derived from a homogeneous lithospheric mantle enriched by an earlier subduction event. After this process, the alkaline magma, from which early clinopyroxenes crystallized, underwent a relatively low-pressure fractional crystallization process. This was in closed magma chambers at different levels of the crust (or within a volcanic conduit system devoid of interaction processes), shown by variations in the different crystallization paths and in the fluid regime of the melt during differentiation and ascent of the magma, in a post-collisional extensional tectonic regime which affected the eastern Pontides during the Neogene.Karadeniz Technical University; Deutscher Akademischer Austauschdienst (DAAD)This work, produced partially from the corresponding author's PhD Thesis, was fully supported by the Scientific Research Projects Funding Center of Karadeniz Technical University, and by a grant from Deutscher Akademischer Austauschdienst (DAAD). The authors would like to give special thanks to Rainer Altherr (Mineralogisches Institut, Universitat Heidelberg, Germany) for his permission to use the electron microprobe. Hans-Peter Meyer (Mineralogisches Institut, Universitat Heidelberg, Germany) and Gultekin Topuz (Eurasia Institute of Earth Sciences, Istanbul Technical University, Turkey) are thanked for their assistance with electron microprobe analyses. Many thanks are given to Peter Moller and Peter Dulski (GeoForschungsZentrum, German Research Centre for Geosciences, Potsdam, Germany) for the trace element and REE analyses. The authors also thank the referees who are Fatma Toksoy Koksal and two anonymous scientists for their precious and kind contributions to improve the quality of the paper. The English of the final text is edited by John A. Winchester

Geochemical and Sr-Nd-Pb isotopic compositions of the Eocene Dolek and Sariqiqek Plutons, Eastern Turkey: Implications for magma interaction in the genesis of high-K calc-alkaline granitoids in a post-collision extensional setting

WOS: 000250247200004The major and trace elements and Sr-Nd-Pb isotopes of the host rocks and the mafic microgranular enclaves (MME) gathered from the Dolek and Saricicek plutons, Eastern Turkey, were studied to understand the underlying petrogenesis and geodynamic setting. ne plutons were emplaced at similar to 43 Ma at shallow depths (similar to 5 to 9 km) as estimated from Al-in hornblende geobarometry. The host rocks consist of a variety of rock types ranging from diorite to granite (SiO2= 56.98-72.67 wt.%; Mg#= 36.8-50.0) populated by MMEs of gabbroic diorite to monzodiorite in composition (SiO2 = 53.21-60.94 wt.%; Mg#=44.4-53.5). All the rocks show a high-K calc-alkaline differentiation trend. Chondrite-normalized REE patterns are moderately fractionated and relatively flat [(La/Yb)(N)=5.11 to 8.51]. They display small negative Eu anomalies (Eu/Eu* =0.62 to 0.88), with enrichment of LILE and depletion of HFSE. Initial Nd-Sr isotopic compositions for the host rocks are epsilon(Nd)(43 Ma)= -0.6 to 0.8 and mostly I-Sr= 0.70482-0.70548. The Nd model ages (T-DM) vary from 0.84 to 0.99 Ga. The Ph isotopic ratios are ((206)pb/(204)pb)= 18.60-18.65, (Pb-207/Pb-204) = 15.61-15.66 and (Pb-208/Pb-204) = 38.69-38.85. Compared with the host rocks, the MMEs are relatively homogeneous in isotopic composition, with Is, ranging from 0.70485 to 0.70517, epsilon(Nd)(4 3 M a) -0.1 to 0.8 and with Pb isotopic ratios of (Pb-206/Pb-204)= 18.58-18.64, (Pb-207/Pb-204)= 15.60-15.66 and (Pb-208/Pb-204)=38.64-38.77. The MMEs have T-DM ranging from 0.86 to 1.36 Ga. The geochemical and isotopic similarities between the MMEs and their host rocks indicate that the enclaves are of mixed origin and are most probably formed by the interaction between the lower crust- and mantle-derived magmas. All the geochemical data, in conjunction with the geodynamic evidence, suggest that a basic magma derived from an enriched subcontinental lithospheric mantle, probably triggered by the upwelling of the asthenophere, and interacted with a crustal melt that originated from the dehydration melting of the mafic lower crust at deep crustal levels. Modeling based on the Sr-Nd isotope data indicates that similar to 77-83% of the subcontinental lithospheric mantle involved in the genesis. Consequently, the interaction process played an important role in the genesis of the hybrid granitoid bodies, which subsequently underwent a fractional crystallization process along with minor amounts of crustal assimilation, en route to the upper crustal levels generating a wide variety of rock types ranging from diorite to granite in an extensional regime. (c) 2007 Elsevier B.V All rights reserved

A study of color back transformation in rainbow trout (Oncorhyncus mykiss) fed by feed containing carotenoids with instrumental (physical) and color card methods

Alabalıkların etindeki pembe kırmızı renk, karotenoid grubu pigmentlerden sağlanmaktadır. Sentetik ve doğal karotenoid maddeler ilave edilerek 3 grup halinde (kırmızı biber ekstraktı, astaksantin ve kantaksantin) pigmentasyonu sağlandıktan sonra ortalama ağırlığı 300 g. ulaşan balıklar 60 gün süre ile karotenoidsiz ticari alabalık yemi ile beslenmiştir. Gökkuşağı alabalıklarından alınan filetoların renkleri enstrümental (CIE L* a* b*) ve renk kartı değerleri kullanılarak renk geri dönüşümü incelenmiş ve a* değeri ile renk kartı değerleri arasındaki ilişki belirlenmiştir. Filetoda renk kartı değerleri azalırken a* (kırmızılık), b* (sarılık) ve L* (parlaklık) değerlerinin de azaldığı bulunmuştur. Deneme başlangıç ve sonunda en yüksek a* ve renk kartı değeri kantaksantin grubunda sırasıyla 9.550, 6.493 ve 15.139, 12.569 bulunmuştur. Gruplar arasında deneme başı ve sonunda renk parametrelerinde bir azalma olmasına rağmen istatistiksel olarak L*, a*, b* değerlerinde bir fark bulunamamıştır (P 0.05). Renk kartı değerleri bakımından grupların deneme başı ve sonu arasında istatistiksel olarak farklar önemli bulunmuştur (P 0.05). Alabalık filetolarının a* ile renk kartı değerleri arasındaki ilişkinin, kırmızı biber ekstraktı grubunda kuvvetli olduğu tespit edilmiştir (r 0.97)Pink red colorotion in rainbow trouts is supplied by pigments from carotenoid. Rainbow trouts with average weightof 300 g. were fed by feed without carotenoid during 60 days after they were pigmented by synthetic and natural carotenoid matters (astaxanthin, canthaxanthin and red pepper oleoresin) as 3 groups. Colour back transformation and relation between a* value and color card values were determined in filet colors by instrumental (CIE L* a* b*) and color card values. While color card values were decreased in fillets, a* (redness), b* (yellowness) and L* (brightness) were also decreased. The highest a* and color card value were 9.550, 6.493 and 15.139, 12.569 in canthaxanthin group at the begining and of the experiment, respectively. Althought there was a decrease in color parameters between groups at the begining and end of the experimental period, there were no significant differences in L*, a* and b* (P 0.05). The difference between the begining and end of the experiment was significant in terms of color card values ( P 0.05). The relationship between a* and color card values was strong in red paprika oleoresin group (r 0.97)