Characterization of a novel polysaccharide from Arca subcrenata and its immunoregulatory activities in vitro and in vivo.

Arca subcrenata is an economical edible shellfish. A novel water-soluble α-D-glucan (ASPG-1) with a molecular weight of 2.56 × 106 Da was purified and characterized from A. subcrenata. Its structure was characterized as a repeating unit consisting of α-D-Glcp, (1 → 6)-α-D-Glcp and (1 → 4,6)-α-D-Glcp. ASPG-1 exerted potent immunoregulatory activity by promoting the viability of splenic lymphocytes. Moreover, it enhanced pinocytic capacity, and promoted the secretion of NO and cytokines in RAW264.7 cells. The immunomodulatory mechanism of ASPG-1 involved the activation of the TLR4-MAPK/Akt-NF-κB signaling pathway. ASPG-1 inhibited tumor growth in 4T1 breast cancer mice and its combination with doxorubicin increased antitumor efficacy. The ASPG-1 combination with DOX-treated group (64.8%) showed an improved tumor inhibition rate compared to that of the DOX-treated group (53.3%). The antitumor mechanism of ASPG-1 may involve an enhancement of the immune response of mice to tumors. These results indicated that ASPG-1 could be developed as a potential adjuvant in tumor immunotherapy.

Molecular cloning, characterization, and tissue distribution of c-Myc from blood clam Tegillarca granosa and its role in cadmium-induced stress response.

Cadmium (Cd) pollution threatens the cultivation of the blood clam Tegillarca granosa (T. granosa) in coastal regions of the East China Sea. The molecular mechanisms regulating Cd stress response and detoxification in blood clams are largely unclear. In the present study, the full-length T. granosa c-Myc (Tgc-Myc) cDNA was cloned for the first time. The 3063-bp cDNA consisted of a 129-bp 5' untranslated region (UTR), a 1746-bp 3' UTR, and a 1188-bp open reading frame encoding a predicted protein of 395 amino acid residues. The predicted protein had a calculated molecular weight of 44.9 kDa and an estimated isoelectric point of 6.82. The predicted protein contained an N-terminal transactivation domain and a C-terminal basic helix-loop-helix leucine zipper domain, which are conserved functional domains of c-Myc proteins. Tgc-Myc showed broad tissue distribution in blood clams, with the highest expression detected in the gill and hepatopancreas. Exposure to Cd, a major heavy metal pollutant in coastal regions of the East China Sea, induced Tgc-Myc expression in gill tissues. Tgc-Myc knockdown led to reduced expression of a variety of stress response/detoxification genes in blood clams cultivated in Cd-contaminated seawater. Tgc-Myc knockdown also led to decreased expression of IGF1R, a proto-oncogene that promotes cell proliferation. These findings indicated that Tgc-Myc regulates Cd-induced stress response and detoxification in blood clams. The upregulation of Tgc-Myc may serve as an approach to generate strains with an enhanced detoxification response and consequently a low heavy metal buildup.

A Novel Peptide Derived from Arca inflata Induces Apoptosis in Colorectal Cancer Cells through Mitochondria and the p38 MAPK Pathway.

Colorectal carcinoma (CRC) is one of the major causes of cancer-related incidence and deaths. Here, we identified a novel antitumor peptide, P6, with a molecular weight of 2794.8 Da from a marine Chinese medicine, Arca inflata Reeve. The full amino acid sequence and secondary structure of P6 were determined by tandem mass de novo sequencing and circular dichroism spectroscopy, respectively. P6 markedly inhibited cell proliferation and colony formation, and induced apoptosis in CRC cells. Mechanistically, transcriptomics analysis and a serial functional evaluation showed that P6 induced colon cancer cell apoptosis through the activation of the p38-MAPK signaling pathway. Moreover, it was demonstrated that P6 exhibited antitumor effects in a tumor xenograft model, and induced cell cycle arrest in CRC cells in a concentration-dependent mode. These findings provide the first line of indication that P6 could be a potential therapeutic agent for CRC treatment.

Effect of ascorbic acid and citric acid on bioavailability of iron from Tegillarca granosa via an in vitro digestion/Caco-2 cell culture system.

Iron deficiency anaemia (IDA) has been receiving worldwide attention. Developing safe and effective iron supplements is of great significance for IDA treatment. Tegillarca granosa (T. granosa), a traditional aquaculture bivalve species in China, is considered to be an excellent source of micronutrients, but the distribution and bioavailability of these minerals have yet to be investigated. The present research was conducted to determine the contents and in vitro enzymatic digestibility of minerals in T. granosa, using beef and wheat flour as reference foods. Meanwhile, two iron-binding proteins, hemoglobin and ferritin, were extracted from T. granosa, and their structures, iron accessibility and bioavailability were investigated. Moreover, the effects of ascorbic acid (AA) and citric acid (CA), two commonly applied dietary factors, on these parameters were evaluated. Our results indicated that the mineral levels varied significantly among different food matrices, with T. granosa showing the highest contents of the tested elements. Comparison of iron absorption of meat versus wheat flour and hemoglobin versus ferritin confirmed that heme iron exhibited higher bioavailability than non-heme iron. The addition of the two organic acids notably enhanced the cellular iron uptake of T. granosa-derived proteins. This could be because AA/CA weakened hydrogen bonds within proteins and caused disordered secondary structures, thereby improving their enzymatic digestibility and releasing more soluble iron to be available for absorption. The results of this study provided a basis for the development of T. granosa-derived protein-based iron supplements, promoting the diverse utilization of marine aquatic resources.

Proximate Composition, Antioxidant Properties, and Hepatoprotective Activity of Three Species of Shellfish of the Pacific Coast of Russia.

The objective of the present study was to investigate the proximate composition, antiradical properties and hepatoprotective activity of three species of shellfish, Corbicula japonica, Spisula sachalinensis, and Anadara broughtonii, from the coastal areas of Far East Russia. Biologically active peptides such as taurine (3.74 g/100 g protein) and ornithine (2.12 g/100 g protein) have been found in the tissues of A. broughtonii. C. japonica contains a high amount of ornithine (5.57 g/100 g protein) and taurine (0.85 g/100 g protein). The maximum DPPH and ABTS radical scavenging activity (36.0 µg ascorbic acid/g protein and 0.68 µmol/Trolox equiv/g protein, respectively) was determined for the tissue of C. japonica. The protein and peptide molecular weight distribution of the shellfish tissue water extracts was investigated using HPLC. It was found that the amount of low molecular weight proteins and peptides were significantly and positively correlated with radical scavenging activity (Pearson's correlation coefficient = 0.96), while the amount of high molecular weight proteins negatively correlated with radical scavenging activity (Pearson's correlation coefficient = -0.86). Hepatoprotective activity, measured by the survival rate of HepG2 hepatocytes after cotreatment with t-BHP, was detected for C. japonica. The highest protection (95.3 ± 2.4%) was achieved by the cold water extract of C. japonica at the concentration of 200 mg/mL. Moreover, oral administration of hot water extract of C. japonica to rats before the treatment with CCl4 exhibited a markedly protective effect by lowering serum levels of ALT and AST, inhibiting the changes in biochemical parameters of functional state of rat liver, including MDA, SOD, GSH and GST.

Purification and characterization of a novel mixed-linkage α,ß-d-glucan from Arca subcrenata and its immunoregulatory activity.

Arca subcrenata Lischke is a seafood with high nutritional value. In this study, we purified and characterized a novel water-soluble polysaccharide (ASPG-2) from Arca subcrenata with significant immunoregulatory effects and no apparent cell toxicity. ASPG-2 is a class of mixed-linkage α,ß-d-glucan backbones with α-linked side chains with a molecular weight of 4.39 × 105 Da. Its structure was characterized as a repeating unit consisting of (1 → 3)-ß-d-Glcp, (1 → 4)-α-d-Glcp, (1 → 4,6)-α-d-Glcp and (1 → 6)-α-d-Glcp. Using mouse RAW264.7 macrophages, we demonstrated that ASPG-2 exerted marked immunoregulatory effects by promoting the secretion of NO and increasing the phagocytosis of RAW264.7 cells in vitro. Moreover, flow cytometry analysis of the expression of the cell surface molecule CD86 revealed that ASPG-2 could polarize RAW264.7 cells into the M1 type. The immunomodulatory mechanism of ASPG-2 in macrophages was associated with the activation of the TLR4-MAPK/Akt-NF-κB signalling pathways. These results indicated that ASPG-2 might be researched and developed as a potential immunomodulatory agent or health product from marine organisms.

Arca subcrenata Polypeptides Inhibit Human Colorectal Cancer HT-29 Cells Growth via Suppression of IGF-1R/Akt/mTOR Signaling and ATP Production.

Arca subcrenata Lischke, widely scattering offshore at neritic regions, is very popular on dining table due to its edible and medical functional meatball. This study aims to investigate the suppression of a polypeptide fraction from A. subcrenata (PAS) on human colorectal cancer HT-29 cells, and its underlying mechanism. The results showed that PAS inhibited the growth of HT-29 cells with an IC50 value of 117 µg/ml after 48 h treatment, and significantly suppressed the tumor growth in nude mice bearing-xenografted HT-29 cells at the dosage of 63 mg/kg, with little influence on normal colon cells and normal colonic mucosa. PAS was then inspiringly found to induce apoptosis and G2/M phase arrest in HT-29 cells. The effect mechanism was involved in the inhibition of IGF-1/IGF-1R signaling activation, which was responsible for inactivating downstream Akt/mTOR pathway. Immunofluorescence assay also showed that PAS could reduce phosphorylation of IGF-1R (Tyr1165/1166). IGF-1, an IGF-1R activator, could reverse the suppression of PAS on IGF-1R phosphorylation. Furthermore, PAS significantly inhibited ATP production of HT-29 cells both in vitro and in vivo. Our results provide positive evidence that A. subcrenata has the potential to be a candidate for the treatment of colorectal cancer.

Two novel peptides from ark shell protein stimulate osteoblast differentiation and rescue ovariectomy-induced bone loss.

Osteoporosis is a common bone disease resulting from imbalance between bone formation and bone resorption. Currently, anti-resorptive agents that inhibit bone resorption are the most available drugs on the market. Biosphosphonates, anti-resorptive drugs most commonly used to treat osteoporosis, are limited by their side effects for long-term continuous treatment. It is important to develop appropriate therapeutic stragegies capable of promoting bone formation to counteract osteoporotic bone loss. Thus, anabolic agents that stimulate bone formation are undoubtedly of interest. Here, we purified and identified two novel osteogenic peptides AWLNH and PHDL from ark shell protein hydrolysates. AWLNH and PHDL stimulated osteoblast differentiation via mitogen-activated protein kinase (MAPK) and bone morphogenetic protein-2 (BMP-2) pathways. The activation of BMP-2 pathway stimulated by AWLNH and PHDL was abolished by treating noggin, BMP antagonist, in bone marrow-derived mesenchymal stem cells (BMMSCs), but not the phosphorylation of JNK1/2, ERK1/2, and p38 MAPK. However, treatment with MAPK inhibitors in BMMSCs downregulated the expression of BMP-2 and p-Smad1/5 and inhibited alkaline phosphatase activity. The dominant inhibitory effects by JNK inhibitor and ERK inhibitor are observed. In ovariectomized (OVX) mice, a reduction of femoral bone mineral density (BMD) was significantly observed, however, AWLNH and PHDL (0.2 mg/kg/per day) injection restored BMD as well as the osteoporotic conditions in OVX mice. Moreover, the increased serum osteocalcin and alkaline phosphatase activity in OVX mice were significantly reduced in AWLNH and PHDL injected-OVX mice. These results suggest that two novel osteogenic peptides AWLNH and PHDL could be attractive therapeutic agents for osteoporosis treatment.

Structural characterization of novel comb-like branched α-d-glucan from Arca inflata and its immunoregulatory activities in vitro and in vivo.

In the current study, we identified and characterized a novel water-soluble polysaccharide (JNY2PW) with significant immunoregulatory effects and no apparent overall toxicity. JNY2PW, which was isolated from Arca inflata, belongs to a novel class of α-glucans with a molecular weight of 5.25 × 107 Da. Its backbone is composed of (1 → 4)-linked α-d-glucopyranosyl residues and a single (1 → 6)-α-d-glucopyranosyl branched unit for every five α-d-glucopyranosyl residues, showing a comb-like α-d-glucan with intensive short branches. Using in vitro models, we demonstrated that JNY2PW exerts significant immunoregulatory effects by promoting the production of nitric oxide, interleukin-6, and tumor necrosis factor α. The pathway involves the activation of the TLR4-MAPK/NF-κB signaling cassette in murine RAW264.7 macrophages. In an in vivo immunosuppressive mice model induced by cyclophosphamide treatment, we found that the JNY2PW treatment produced good antitumor activity, comparable to that of chemotherapy by doxycycline in murine breast carcinoma 4T1-bearing mice, but devoid of any observable side effects (e.g. weight loss) related with doxycycline treatment. The anti-tumor mechanism of JNY2PW may involve an overall enhancement in the immune responses of the mice to tumors. These results indicate that JNY2PW possesses potential as an adjuvant to existing chemotherapy and current immune-oncology treatment.

Identification and Characterization of a Novel Protein ASP-3 Purified from Arca subcrenata and Its Antitumor Mechanism.

Diverse bioactive substances derived from marine organisms have been attracting growing attention. Besides small molecules and polypeptides, numerous studies have shown that marine proteins also exhibit antitumor activities. Small anticancer proteins can be expressed in vivo by viral vectors to exert local and long-term anticancer effects. Herein, we purified and characterized a novel protein (ASP-3) with unique antitumor activity from Arca subcrenata Lischke. The ASP-3 contains 179 amino acids with a molecular weight of 20.6 kDa. The spectral characterization of ASP-3 was elucidated using Fourier Transform infrared spectroscopy (FTIR) and Circular Dichroism (CD) spectroscopy. Being identified as a sarcoplasmic calcium-binding protein, ASP-3 exhibited strong inhibitory effects on the proliferation of Human hepatocellular carcinoma (HepG2) cells with an IC50 value of 171.18 ± 18.59 µg/mL, measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The RNA-seq analysis showed that ASP-3 regulated the vascular endothelial growth factor receptor (VEGFR) signaling pathway in HepG2 cells. Immunofluorescence results indicated that ASP-3 effectively reduced VEGFR2 phosphorylation in HepG2 cells and affected the downstream components of VEGF signaling pathways. The surface plasmon resonance (SPR) analysis further demonstrated that ASP-3 direct interacted with VEGFR2. More importantly, the therapeutic potential of ASP-3 as an anti-angiogenesis agent was further confirmed by an in vitro model using VEGF-induced tube formation assay of human umbilical vein endothelial cells (HUVECs), as well as an in vivo model using transgenic zebrafish model. Taken together, the ASP-3 provides a good framework for the development of even more potent anticancer proteins and provides important weapon for cancer treatment using novel approaches such as gene therapy.

Metal concentrations in Sydney Cockle (Anadara trapezia) tissue and ambient sediment in a highly-modified estuary (Sydney estuary, Australia).

The influence of sedimentary metals on the cockle A. trapezia tissue was examined using a strong difference in sedimentary metal concentrations in an embayment (Hen and Chicken Bay) highly contaminated in Cu and an adjacent cove (Iron Cove), strongly enriched in Cd, Cu, Pb and Zn within the heavily-urbanised Sydney estuary catchment (Australia). Statistically significant differences were recorded for cockle tissue metal concentrations between the study locations reflecting differences in surficial sediment metal concentrations. Low metal uptake was apparent in A. trapezia tissue, which were considerably less than background sedimentary concentrations and was of low-risk for human consumption. Dissimilar bioconcentration of Cd, Cu, Pb and Zn was apparent in tissue of cockles (A. trapezia), prawns (Metapenaeus bennettae), mussels (Mytilus galloprovincialis) and oysters (Saccostrea glomerata), due possibly to different feeding patterns and biogeochemical conditions in bottom sediments.

Changes in the tissue concentrations of trace elements during the reproductive cycle of Noah's Ark shells (Arca noae Linnaeus, 1758).

Concentrations of 23 trace elements (TEs; essential: Co, Cu, Fe, Mn, Mo, Se, V, Zn; non-essential: Ag, Al, As, Ba, Cd, Cr, Cs, Li, Ni, Pb, Rb, Sr, Ti, Tl, U) in whole soft tissues of Noah's Ark shell (Arca noae) were determined monthly during one year (March 2013-February 2014) at two sampling sites in the central part of the Eastern Adriatic Sea. Our aim was to detect the influence of reproductive cycle and changes in the environmental factors on the variabilities of TEs' contents. Higher concentrations of Pb, Ba, V, Mo, Mn and Fe were found at potentially contaminated site in Pasman channel, whereas higher concentrations of Tl, Ni, Li, Cr, Cd, Ti and Se were found at reference site in Nature Park Telascica. Since several bioaccumulated TEs were associated to mean gonadal index, in TEs monitoring in A. noae, animal gonadal status has to be considered.

Inhibitory activity of bio-active compounds isolated from Anadara granosa in shrimp health management.

The crude extract isolated from the visceral mass of Anadara granosa, an intertidal bivalve mollusc was tested for inhibitory activity against pathogenic bacteria of the shrimp and fish viz. Vibrio harveyi and Staphylococcus aureus respectively by agar well diffusion and contact bioautography methods. Maximum inhibitory activity was shown against V. harveyi by methanol and chloroform (9:1) extract. Twelve fractions (1-12) could be separated from the crude extract through column chromatography. Five out of twelve fractions (7, 8, 9, 10, and 11) showed antibacterial activity and they were further run on column chromatography for purity. The fraction no. 9 showed highest antibacterial activity among the five and was subjected to NMR for the proton, C13 and H1-H1 correlation, IR and mass spectral analysis for structural elucidation. Structure of the compound isolated from fraction no: 9 was determined as 1-(((2Z, 4Z)-dodeca-2,4-dienoyl)oxy)-3-hydroxypropan-2-yl tetradecanoate.

Purification and structural characterization of a novel anti-tumor protein from Arca inflata.

A novel in vitro anti-tumor protein (J2-C2) with a molecular weight of 27,153.0Da was isolated from the edible portion of Arca inflata. Physical and structural properties of J2-C2 were characterized using physicochemical and instrumental analyses. Gel electrophoresis analysis showed that J2-C2 is a homogeneous, monomeric protein with an isoelectric point of 6.3. The purity of the isolated native J2-C2 was >99%, as determined by RP-HPLC. The carbohydrate content assay showed that J2-C2 was not a glycoprotein. The FT-IR spectrum of J2-C2 gave characteristic amide absorption bands at 1645.71 and 1541.46cm-1. Secondary structure analysis by CD spectroscopy revealed that J2-C2 had 34.0% α-helix, 27.5% ß-sheet, 13.4% ß-turn and 25.1% random coil. In-gel and nano ESI-MS/MS sequencing analysis combined with transcriptome unigene analysis yielded the complete amino acid sequence of J2-C2. Aligning with NCBI BLAST database, J2-C2 showed 77% homology with predicted triosephosphate isomerase (TIM) derived from Crassostrea gigas. Therefore, J2-C2 was considered to be a new TIM-like protein in A. inflata. The anti-tumor effect of J2-C2 against three human tumor cells was measured by MTT assay, and the IC50 values of J2-C2 were 42.38, 45.64 and 48.73µM against A549, HepG2 and SPC-A-1 cell lines, respectively.

Antibacterial Activity of AI-Hemocidin 2, a Novel N-Terminal Peptide of Hemoglobin Purified from Arca inflata.

The continued emergence of antibiotic resistant bacteria in recent years is of great concern. The search for new classes of antibacterial agents has expanded to non-traditional sources such as shellfish. An antibacterial subunit of hemoglobin (Hb-I) was purified from the mantle of Arcainflata by phosphate extraction and ion exchange chromatography. A novel antibacterial peptide, AI-hemocidin 2, derived from Hb-I, was discovered using bioinformatics analysis. It displayed antibacterial activity across a broad spectrum of microorganisms, including several Gram-positive and Gram-negative bacteria, with minimal inhibitory concentration (MIC) values ranging from 37.5 to 300 µg/mL, and it exhibited minimal hemolytic or cytotoxic activities. The antibacterial activity of AI-hemocidin 2 was thermostable (25-100 °C) and pH resistant (pH 3-10). The cellular integrity was determined by flow cytometry. AI-hemocidin 2 was capable of permeating the cellular membrane. Changes in the cell morphology were observed with a scanning electron microscope. Circular dichroism spectra suggested that AI-hemocidin 2 formed an α-helix structure in the membrane mimetic environment. The results indicated that the anti-bacterial mechanism for AI-hemocidin 2 occurred through disrupting the cell membrane. AI-hemocidin 2 might be a potential candidate for tackling antibiotic resistant bacteria.

Purification and characterization of an antibacterial and anti-inflammatory polypeptide from Arca subcrenata.

A polypeptide coded as PGC was isolated from Arca subcrenata muscle using ion exchange, Sephadex G-50 gel chromatography and RP-HPLC. PGC was identified to be a homogeneous compound by Native-PAGE and the purity was more than 98.9% measured by HPLC. The isoelectric point of PGC was determined to be 9.76 by IEF-PAGE. The molecular weight was determined to be 15,973.0Da by ESI-MS/MS. The conformational structure of PGC was characterized by UV-vis, FT-IR and CD spectroscopy. N terminal amino acid sequence of PGC was shown as PSVYDAAAQLTADVKKDLRDSWKVIGGDKKGNGVA by Edman degradation. The results demonstrated that there is a high degree of homology between PGC and the subunit from hemoglobin, and proposed that PGC is the depolymerized polypeptide of Hemoglobin I (HbI) from A. subcrenata. The evaluation of biological activities showed that the diameters of the inhibitory ring of PGC on Escherichia coli and Staphylococcus aureus were 14.5±0.44mm and 16.5±1.15mm, respectively. The IC50 of inhibition rate for PGC on NO production was 9.60±0.71µg/mL. Therefore, PGC might be developed as one of potential antibacterial and anti-inflammatory agents.

Identification of a regulation network in response to cadmium toxicity using blood clam Tegillarca granosa as model.

Clam, a filter-feeding lamellibranch mollusk, is capable to accumulate high levels of trace metals and has therefore become a model for investigation the mechanism of heavy metal toxification. In this study, the effects of cadmium were characterized in the gills of Tegillarca granosa during a 96-hour exposure course using integrated metabolomic and proteomic approaches. Neurotoxicity and disturbances in energy metabolism were implicated according to the metabolic responses after Cd exposure, and eventually affected the osmotic function of gill tissue. Proteomic analysis showed that oxidative stress, calcium-binding and sulfur-compound metabolism proteins were key factors responding to Cd challenge. A knowledge-based network regulation model was constructed with both metabolic and proteomic data. The model suggests that Cd stimulation mainly inhibits a core regulation network that is associated with histone function, ribosome processing and tight junctions, with the hub proteins actin, gamma 1 and Calmodulin 1. Moreover, myosin complex inhibition causes abnormal tight junctions and is linked to the irregular synthesis of amino acids. For the first time, this study provides insight into the proteomic and metabolomic changes caused by Cd in the blood clam T. granosa and suggests a potential toxicological pathway for Cd.

Elemental profiling of Noah's Ark shell (Arca noae, Linnaeus, 1758) by plasma optical spectrometry and chemometric tools.

Determination of metal content in biominerals provides essential information with respect to relations between biomineralization processes and environmental status. Mussels are species that have a great potential as bio-marker species and therefore, they are in the focus of numerous biomineralization and ecological studies. In this study, elemental profile of mussel shell of Noah's Ark (Arca noe, Linnaeus, 1758), which inhabit eastern Adriatic Sea was obtained by determination of seventeen elements content using inductively coupled plasma optical emission spectrometry (ICP-OES). Shell samples were collected from marine protected area and from marine shipping route in eastern Adriatic Sea. The accuracy of applied analytical procedure based on microwave decomposition of shell samples was tested by use of reference materials of limestone and by matrix-matched standards. By aid of chemometric methods, the elemental profile along with variability of elements content of shell was obtained. The impact of different environment on elements content was established by use of multivariate statistical PCA method. Discernment between two groups of samples was manifested. Among results of main, minor and trace elements content, the last one which denoted to Cd, Co, Cu, Pb, and Mn was expressed as principal distinctive feature of shell samples collected from different sampling sites. Elemental profiling of mussel shell Noah's Ark provides novel insight in species status as well as in environmental status on the observed locations.

[Micronutrient structure of food parts of a trade bivalve mollusc of Anadara broughtoni].

The content of micronutrients in food parts of a bivalve mollusk of the Far East region of Anadara broughtoni has been defined. It is established that in a muscle the prevailing mineral is potassium, in a cloak with a adductor--sodium. In Anadara broughtoni muscle concentration of potassium reaches 490 mg/100 g of crude tissue that is 2-3 fold higher than the content of this element in combs and oysters and 4 fold above, than in a cloak. For sodium inverse relationship is observed: its contents in a cloak (439 mg/100 g) is 3 fold more, than in a muscle. The low content of sodium in an adductor should be noted. For all food parts of a mollusk of Anadara broughtoni the dominating trace elements are iron and zinc. The content of iron is maximum in a muscle (4.84 mg/100 g) and exceeds that in an adductor by 1.84 fold. The content of zinc in food parts differs insignificantly, the maximum contents is defined in a cloak (2.12 mg/100 g), in comparison with an adductor excess makes only 15%. It should be noted the high content of manganese--especially in a cloak (1.12 mg/100 g)--in comparison with an adductor 43.5% more. Chromium content in a muscle (0.018 mg/100 g) exceeds that in an adductor 2.25 times. The high content of copper in a muscle (0.04 mg/100 g)--4 times old higher than in an adductor is defined. The content of selenium and of iodine is maximum in a muscle (0.03 mg/100 g). For a cloak and a muscle the prevailing class of lipids are phospholipids, for an adductor--cholesterol. The content of cholesterol in an adductor is 2 7-37% more, than in other food parts of a mollusk. The level of total carotenoids in a motive muscle (5.7 mg/100 g) 1.78 fold exceeds the contents in an adductor and by 1.5 fold elevates the contents in a cloak. The main share of carotenoids is concentrated in a motive muscle.

Accumulation of Trace Metals in Anadara granosa and Anadara inaequivalvis from Pattani Bay and the Setiu Wetlands.

This study was undertaken to assess the levels of trace metals (As, Cd, Cu, Pb, and Zn) in two common species of cockles (Anadara granosa and Anadara inaequivalvis) from two coastal areas in Thailand (Pattani Bay) and Malaysia (the Setiu Wetlands). A total of 350 cockles were collected in February and September 2014. Trace metals were determined by Inductively Coupled Plasma Mass Spectrometry. We observed that cockles in both areas had a higher accumulation of metals in September. Notably, the biota-sediment accumulation (BSAF) of Cd was highest in both areas. A strong positive correlation of Cd with the length of the cockles at Pattani Bay (r(2) = 0.597) and the Setiu Wetlands (r(2) = 0.675) was noted. It was suggested that As could be a limiting element (BSAF < 1) of cockles obtained from Pattani Bay. In comparison with the permissible limits set by the Thailand Ministry of Public Health and the Malaysia Food Regulations, mean values of As, Cd, Cu, Pb, and Zn were within acceptable limits, but the maximum values of Cd and Pb exceeded the limits for both areas. Regular monitoring of trace metals in cockles from both areas is suggested for more definitive contamination determination.