An arithmetic correction for the effect of lipid on carbon stable isotope ratios in muscle and digestive glands of the American lobster (Homarus americanus).

RATIONALE: Lipid correction models use elemental carbon-to-nitrogen ratios to estimate the effect of lipids on δ13 C values and provide a fast and inexpensive alternative to chemically removing lipids. However, the performance of these models varies, especially in whole-body invertebrate samples. The generation of tissue-specific lipid correction models for American lobsters, both an ecologically and an economically important species in eastern North America, will aid ecological research of this species and our understanding of the function of these models in invertebrates. METHOD: We determined the δ13 C and δ15 N values before and after lipid extraction in muscle and digestive glands of juvenile and adult lobster. We assessed the performance of four commonly used models (nonlinear, linear, natural logarithm (LN) and generalized linear model (GLM)) at estimating lipid-free δ13 C values based on the non-lipid-extracted δ13 C values and elemental C:N ratios. The accuracy of model predictions was tested using paired t-tests, and the performance of the different models was compared using the Akaike information criterion score. RESULTS: Lipid correction models accurately estimated post-lipid-extraction δ13 C values in both tissues. The nonlinear model was the least accurate for both tissues. In muscle, the three other models performed well, and in digestive glands, the LN model provided the most accurate estimates throughout the range of C:N values. In both tissues, the GLM estimates were not independent of the post-lipid-extraction δ13 C values, thus reducing their transferability to other datasets. CONCLUSIONS: Whereas previous work found that whole-body models poorly estimated the effect of lipids in invertebrates, we show that tissue-specific lipid correction models can generate accurate and precise estimates of lipid-free δ13 C values in lobster. We suggest that the tissue-specific logarithmic models presented here are the preferred models for accounting for the effect of lipid on lobster isotope ratios.

Inhibition of Proinflammatory Enzymes and Attenuation of IL-6 in LPS-Challenged RAW 264.7 Macrophages Substantiates the Ethnomedicinal Use of the Herbal Drug Homalium bhamoense Cubitt & W.W.Sm.

Commonly used to treat skin injuries in Asia, several Homalium spp. have been found to promote skin regeneration and wound healing. While ethnobotanical surveys report the use of H. bhamoense trunk bark as a wound salve, there are no studies covering bioactive properties. As impaired cutaneous healing is characterized by excessive inflammation, a series of inflammatory mediators involved in wound healing were targeted with a methanol extract obtained from H. bhamoense trunk bark. Results showed concentration-dependent inhibition of hyaluronidase and 5-lipoxygenase upon exposure to the extract, with IC50 values of 396.9 ± 25.7 and 29.0 ± 2.3 µg mL-1, respectively. H. bhamoense trunk bark extract also exerted anti-inflammatory activity by significantly suppressing the overproduction of interleukin 6 (IL-6) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages at concentrations ranging from 125 to 1000 µg mL-1, while leading to a biphasic effect on nitric oxide (NO) and tumor necrosis factor alpha (TNF-α) levels. The phenolic profile was elucidated by HPLC-DAD, being characterized by the occurrence of ellagic acid as the main constituent, in addition to a series of methylated derivatives, which might underlie the observed anti-inflammatory effects. Our findings provide in vitro data on anti-inflammatory ability of H. bhamoense trunk bark, disclosing also potential cutaneous toxicity as assessed in HaCaT keratinocytes.

Quantitative determination of the neurotoxin ß-N-methylamino-L-alanine (BMAA) by capillary electrophoresis-tandem mass spectrometry.

Recent reports of the widespread occurrence of the neurotoxin ß-N-methylamino-L-alanine (BMAA) in cyanobacteria and particularly seafood have raised concerns for public health. LC-MS/MS is currently the analytical method of choice for BMAA determinations but incomplete separation of isomeric and isobaric compounds, matrix suppression and conjugated forms are plausible limitations. In this study, capillary electrophoresis (CE) coupled with MS/MS has been developed as an alternative method for the quantitative determination of free BMAA. Using a bare fused silica capillary, a phosphate buffer (250 mM, pH 3.0) and UV detection, it was possible to separate BMAA from four isomers, but the limit of detection (LOD) of 0.25 µg mL-1 proved insufficient for analysis of typical samples. Coupling the CE to a triple quadrupole MS was accomplished using a custom sheath-flow interface. The best separation was achieved with a 5 M formic acid in water/acetonitrile (9:1) background electrolyte. Strong acid hydrolysis of lyophilized samples was used to release BMAA from conjugated forms. Field-amplified stacking after injection was achieved by lowering sample ionic strength with a cation-exchange cleanup procedure. Quantitation was accomplished using isotope dilution with deuterium-labelled BMAA as internal standard. An LOD for BMAA in solution of 0.8 ng mL-1 was attained, which was equivalent to 16 ng g-1 dry mass in samples using the specified extraction procedure. This was comparable with LC-MS/MS methods. The method displayed excellent resolution of amino acid isomers and had no interference from matrix components. The presence of BMAA in cycad, mussel and lobster samples was confirmed by CE-MS/MS, but not in an in-house cyanobacterial reference material, with quantitative results agreeing with those from LC-MS/MS. Graphical Abstract CE-MS separation and detection of BMAA, its isomers and the internal standard BMAA-d3.

Lipid Composition of Oil Extracted from Wasted Norway Lobster (Nephrops norvegicus) Heads and Comparison with Oil Extracted from Antarctic Krill (Euphasia superba).

In the UK, the Norway lobster (Nephrops norvegicus) supports its most important shellfish fishery. Nephrops are sold either whole, or as "tails-only" for the scampi trade. In the "tailing" process, the "head" (cephalothorax) is discarded as waste. A smaller crustacean species, the Antarctic krill Euphasia superba, represents an economically valuable industry, as its extractable oil is sold as a human dietary supplement. The aim of this study was to determine the amount and composition of the oil contained in discarded Nephrops heads and to compare its composition to the oil extracted from krill. Differences due to Geographical variation and seasonal patterns in the amount and composition of lipid were also noted. Results indicated that Nephrops head waste samples collected from more southern locations in Scotland (Clyde Sea area) contained higher levels of oil when compared to samples collected from northern locations in Iceland. Moreover, seasonal differences within the Clyde Sea area in Scotland were also observed, with oil extracted from Nephrops head waste peaking at around 11.5% during the summer months when larger and more mature females were caught by trawl. At this time of the year, the valuable fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) accounted for around 23% of the total fatty acid content in oil extracted from Nephrops head waste. A seasonal effect on EPA content was found, with higher levels obtained in the summer, while no trend was found in DHA percentages. Finally, oil from Nephrops head waste contained a higher proportion of EPA and DHA than krill oil but these fatty acids were more abundantly linked to the neutral lipids rather to than polar lipids. The characterization of lipid that could be extracted from Nephrops head waste should be seen as a first step for the commercial use of a valuable resource currently wasted. This approach is extremely relevant given the current limited supply of EPA and DHA and changes in the Common Fisheries Policy.

Mechanosensitive membrane probes.

This article assembles pertinent insights behind the concept of planarizable push-pull probes. As a response to the planarization of their polarized ground state, a red shift of their excitation maximum is expected to report on either the disorder, the tension, or the potential of biomembranes. The combination of chromophore planarization and polarization contributes to various, usually more complex processes in nature. Examples include the color change of crabs or lobsters during cooking or the chemistry of vision, particularly color vision. The summary of lessons from nature is followed by an overview of mechanosensitive organic materials. Although often twisted and sometimes also polarized, their change of color under pressure usually originates from changes in their crystal packing. Intriguing exceptions include the planarization of several elegantly twisted phenylethynyl oligomers and polymers. Also mechanosensitive probes in plastics usually respond to stretching by disassembly. True ground-state planarization in response to molecular recognition is best exemplified with the binding of thoughtfully twisted cationic polythiophenes to single- and double-stranded oligonucleotides. Molecular rotors, en vogue as viscosity sensors in cells, operate by deplanarization of the first excited state. Pertinent recent examples are described, focusing on λ-ratiometry and intracellular targeting. Complementary to planarization of the ground state with twisted push-pull probes, molecular rotors report on environmental changes with quenching or shifts in emission rather than absorption. The labeling of mechanosensitive channels is discussed as a bioengineering approach to bypass the challenge to create molecular mechanosensitivity and use biological systems instead to sense membrane tension. With planarizable push-pull probes, this challenge is met not with twistome screening, but with "fluorescent flippers," a new concept to insert large and bright monomers into oligomeric probes to really feel the environment and also shine when twisted out of conjugation.

Post-mortem recrystallization of biogenic amorphous calcium carbonate guided by the inherited macromolecular framework.

In contrast to abiotically formed carbonates, biogenetic carbonates have been observed to be nanocomposite, organo-mineral structures, the basic build-blocks of which are particles of quasi-uniform size (10-100 nm) organized into complex higher-order hierarchical structures, typically with highly controlled crystal-axis alignments. Some of these characteristics serve as criteria for inferring a biological origin and the state of preservation of fossil carbonate materials, and to determine whether the biomineralization process was biologically induced or controlled. Here we show that a calcium storage structure formed by the American lobster, a gastrolith initially consisting of amorphous calcium carbonate (ACC) and amorphous calcium phosphate (ACP), post-mortem can crystallize into (thus secondary) calcite with structural properties strongly influenced by the inherited organic matrix. This secondary calcite meets many structural criteria for biominerals (thus called the biomorphic calcite), but differs in trace element distributions (e.g., P and Mg). Such observations refine the capability to determine whether a fossil carbonates can be attributed to biogenic processes, with implications for the record of life on Earth and other terrestrial planets.

Comparative efficiency of different polyol-based deep eutectic solvents for chitin extraction from lobster shells.

In this study, deep eutectic solvent (DES) prepared from choline chloride, lactic acid, and one of the four polyols (ethylene glycol, glycerol, xylitol, and sorbitol) were compared and assessed for their effectiveness in extracting chitin from lobster shells. Our results revealed that as the number of hydroxyl groups in polyols increased, the hydrogen bond network within the DESs became denser. However, this led to a corresponding increase in viscosity, which impacted the efficiency of chitin extraction. Among all prepared DESs, choline chloride-lactic acid/glycerol (CCLaGly) exhibited superior extractive ability, resulting in the extraction of pure chitin from lobster shells. The purity, crystallinity, and molecular weight of the extracted chitin using CCLaGly DES were comparable to those of chemically-isolated chitin, with purity reaching 94.76 ± 0.33 %, crystallinity at 78.78 %, and a molecular weight of 655 kDa. Additionally, the physicochemical properties of the DES-extracted chitins were characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. This study conducted a comparative analysis of polyol effects on chitin extraction from lobster shells, thereby opening a promising avenue for the utilization of various crustacean shells in sustainable biomaterial production.

Isoforms of gelsolin from lobster striated muscles differ in calcium-dependence.

Two distinct isoforms of the Ca-dependent actin filament severing protein gelsolin were identified in cross-striated muscles of the American lobster. The variants (termed LG1 and LG2) differ by an extension of 18 AA at the C-terminus of LG1, and by two substitutions at AA735 and AA736, the two C-terminal amino acids of LG2. Functional comparison of the isolated and purified proteins revealed gelsolin-typical properties for both with differences in Ca(2+)-sensitivity, LG2 being activated at significant lower Ca-concentration than LG1: Half maximal activation for both filament severing and G-actin binding was ∼4×10(-7)M Ca(2+) for LG2 vs. ∼2×10(-6)M Ca(2+) for LG1. This indicates a differential activation for the two isoproteins in vivo where they are present in almost equal amounts in the muscle cell. Structure prediction modeling on the basis of the known structure of mammalian gelsolin shows that LG2 lacks the C-terminal alpha-helix which is involved in contact formation between domains G6 and G2. In both mammalian gelsolin and LG1, this "latch bridge" is assumed to play a critical role in Ca(2+)-activation by keeping gelsolin in a closed, inactive conformation at low [Ca(2+)]. In LG2, the reduced contact between G6 and G2 may be responsible for its activation at low Ca(2+)-concentration.

Defensin like peptide from Panulirus argus relates structurally with beta defensin from vertebrates.

Naturally occurring antimicrobial peptides take place in the first line of host defense against pathogen as part of the humoral innate immune response. ß-defensins are among the most abundant antimicrobial peptides in mammals, and thought to be solely found in vertebrates until a recent report describing the cloning and sequencing of defensin like peptides in the spiny lobster Panulirus japonicus. In the current study, we cloned and sequenced two genes from the hemocytes of the spiny lobster Panulirus argus encoding for two isoforms of defensin-like peptides, thus confirming the presence of this protein in the Panulirus genus. The 44 amino acids mature peptides showed the conservation of cysteine pattern characterizing the ß-defensins, as well as known amino acids residues critical to exert their antimicrobial activity. They are also amphipathics, hydrophobics, and display an overall positive charge (+1) located at the C-terminus. The tertiary structure obtained by homology modeling indicated that likely conformations of lobster peptides are highly similar to ß-defensins from vertebrates. The phylogenetic study carried out by probabilistic methods confirmed the relation with ancestral ß-defensin from vertebrates. The finding of a putative defensin-like peptide in the expressed sequence tag (EST) of the lobster Homarus americanus with high homology with those of P. argus described in this study, would indicate the presence of this peptides in Palinuridae family. Taking into account all similarities between these peptides with ß-defensins from vertebrates, it is conceivable to further support the finding of a new family of ß-defensins in invertebrate.

Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus.

Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H(1) and H(2) from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H(1) and H(2) with astaxanthin reproduced the bathochromic shift of 85-95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype-phenotype linkage.

Eco-friendly isolation and characterization of nanochitin from different origins by microwave irradiation: Optimization using response surface methodology.

The extraction of nanochitin from marine waste has attracted great industrial interest due to its unique properties, namely biodegradability, biocompatibility and as a functional reinforcing agent. Conventional acid hydrolysis isolation of nanochitin requires high temperatures and acid concentration, time and energy. Herein, for the first time, microwave irradiation method was used as an eco-friendly approach to isolate nanochitin from different sources. The isolation conditions were optimized through an experimental Box-Behnken design using surface response methodology. The data showed optimal conditions of 1 M HCl, 10.00 min and 124.75 W to obtain lobster nanocrystals; 1 M HCl, 14.34 min and 50.21 W to obtain shrimp nanocrystals; and 1 M HCl, 29.08 min and 54.08 W to obtain squid pen nanofibres, reducing time and HCl concentration. The obtained isolation yields where of 85.30, 79.92 and 80.59 % for lobster, shrimp and squid, respectively. The morphology of the nanochitins was dependent of the chitin origin, and the lengths of the nanochitins were of 314.74, 386.12 and > 900 nm for lobster, shrimp and squid pen, respectively. The thermal stability of the ensuing nanochitins was maintained after treatment. The results showed that nanochitin could be obtained by using an eco-friendly approach like microwave irradiation.

Lobster Supply Chains Are Not at Risk from Paralytic Shellfish Toxin Accumulation during Wet Storage.

Lobster species can accumulate paralytic shellfish toxins (PST) in their hepatopancreas following the consumption of toxic prey. The Southern Rock Lobster (SRL), Jasus edwardsii, industry in Tasmania, Australia, and New Zealand, collectively valued at AUD 365 M, actively manages PST risk based on toxin monitoring of lobsters in coastal waters. The SRL supply chain predominantly provides live lobsters, which includes wet holding in fishing vessels, sea-cages, or processing facilities for periods of up to several months. Survival, quality, and safety of this largely exported high-value product is a major consideration for the industry. In a controlled experiment, SRL were exposed to highly toxic cultures of Alexandrium catenella at field relevant concentrations (2 × 105 cells L-1) in an experimental aquaculture facility over a period of 21 days. While significant PST accumulation in the lobster hepatopancreas has been reported in parallel experiments feeding lobsters with toxic mussels, no PST toxin accumulated in this experiment from exposure to toxic algal cells, and no negative impact on lobster health was observed as assessed via a wide range of behavioural, immunological, and physiological measures. We conclude that there is no risk of PST accumulation, nor risk to survival or quality at the point of consumption through exposure to toxic algal cells.

UV Photochemical vapor generation sample introduction for determination of Ni, Fe, and Se in biological tissue by isotope dilution ICPMS.

A novel, sensitive method is described for the accurate determination of Ni, Se, and Fe in biological tissues by isotope dilution inductively coupled plasma mass spectrometry (ID ICPMS) based on sample introduction arising from online UV photochemical vapor generation (UV-PVG). Volatile species of Ni, Se, and Fe were liberated from a formic acid medium following exposure to a UV source. Sensitivities were enhanced 27- to 355-fold compared to those obtained using pneumatic nebulization sample introduction. Although precision was slightly degraded (a factor of 2) with ultraviolet photochemical mediated vapor generation (UV-PVG), limits of detection (LODs) of 0.18, 1.7, and 1.0 pg g(-1) for Ni, Se, and Fe, respectively, based on an external calibration, provided 28-, 150-, and 29-fold improvements over that realized with conventional pneumatic solution nebulization. Method validation was demonstrated by determination of Ni, Se, and Fe in biological tissue certified reference materials (CRMs) TORT-2 and DORM-3. Concentrations of 2.33 +/- 0.03, 5.80 +/- 0.28, and 109 +/- 2 microg g(-1) (1SD, n = 4) and 1.31 +/- 0.04, 3.35 +/- 0.18, and 353 +/- 5 microg g(-1) (1SD, n = 4) for Ni, Se, and Fe, respectively were obtained in TORT-2 and DORM-3, in good agreement with certified values.

Electron-microscopical localization of gelsolin in various crustacean muscles.

Gelsolin was localized by immunoelectron microscopy in fast and slow cross-striated muscles of the lobster Homarus americanus. When ultrathin sections of the muscles were labelled with anti-gelsolin and a gold-conjugated second antibody, 90% of all gold particles in the myoplasm were detected on myofibrils, preferentially in the I-band and AI-region of the sarcomeres. Both the region of the H-zone (lacking thin filaments) and the Z-disc contained no or little gold label. Under physiological conditions, a close association of gelsolin with the thin filaments was observed for both muscle types. The preferential localization of particles in the I- and AI-region indicated that gelsolin was distributed randomly over the whole length of the thin filaments. Preincubation of muscle strips with Ringer solution containing 0.5 mM EGTA resulted in a significantly different distribution pattern; gold particles were now localized preferentially in the cell periphery close to the sarcolemma, with significantly decreased abundance in the centre of the cell. Compared with the muscle under physiological conditions, the number of gold particles over sarcomeric structures was significantly reduced. Thus, binding of gelsolin to the thin filaments is apparently reversible in vivo and depends on the presence of calcium ions. We assume a functional role for gelsolin in the actin turnover processes in invertebrate muscle systems.

Natural hydrogel in American lobster: A soft armor with high toughness and strength.

Homarus americanus, known as American lobster, is fully covered by its exoskeleton composed of rigid cuticles and soft membranes. These soft membranes are mainly located at the joints and abdomen to connect the rigid cuticles and greatly contribute to the agility of the lobster in swimming and preying. Herein, we show that the soft membrane from American lobster is a natural hydrogel (90% water) with exceptionally high toughness (up to 24.98 MJ/m3) and strength (up to 23.36 MPa), and is very insensitive to cracks. By combining experimental measurements and large-scale computational modeling, we demonstrate that the unique multilayered structure in this membrane, achieved through the ordered arrangement of chitin fibers, plays a crucial role in dissipating energy during rupture and making this membrane tough and damage tolerant. The knowledge learned from the soft membrane of natural lobsters sheds light on designing synthetic soft, yet strong and tough materials for reliable usage under extreme mechanical conditions, including a flexible armor that can provide full-body protection without sacrificing limb mobility. STATEMENT OF SIGNIFICANCE: A body armor to provide protection to people who are at risk of being hurt is only enabled by using a material that is tough and strong enough to prevent mechanical penetration. However, most modern body armors sacrifice limb protection to gain mobility, simply because none of the existing armor materials are flexible enough and they all inhibit movement of the arms and legs. Herein, we focus on the mechanics and mesoscopic structure of American lobsters' soft membrane and explore how such a natural flexible armor is designed to integrate flexibility and toughness. The knowledge learned from this study is useful to design a flexible armor for full-body protection under extreme mechanical conditions.

Physicochemical Properties and Consumer Acceptance of High-Pressure Processed, Sous Vide-Cooked Lobster Tails.

Sous vide (SV) and high-pressure processing (HPP) are promising techniques in the development of high-quality seafood products. The objectives of this study were to evaluate the impacts of HPP on the physicochemical quality and consumer acceptance of subsequently SV-cooked lobster tails. Raw shucked lobster tails were processed at 150 or 350 MPa for 5 or 10 min. Subsequently, half were SV cooked to a core temperature of 65 °C/10 min. Texture profile analysis, shear force, color, salt soluble protein content, water-holding capacity (WHC), moisture content, and weight loss were analyzed. Pressurization at 150 MPa/10 min decreased (P < 0.05) the hardness of raw lobsters compared to non-HPP-treated controls. However, 350 MPa for 5 or 10 min increased (P < 0.05) the shear force in raw and SV-cooked samples. HPP increased (P < 0.05) the L* values but did not affect moisture content, WHC, or weight loss of raw or SV-cooked lobsters. Lobsters were subjected to consumer acceptability testing using a 9-point hedonic scale. Although panelists rated the flavor, texture, and overall liking of the 350 MPa/10 min samples higher than the control and 150 MPa/10 min samples, there were no significant differences among treatment means, indicating that physicochemical changes induced by HPP did not affect consumer acceptance. In addition, approximately 84% of panelists reported that the 350 MPa product met their expectations compared to approximately 75% for the control and 150 MPa treatments. These results suggest that HPP has the potential to be applied in combination with SV cooking to produce consumer-acceptable, value-added lobster products. PRACTICAL APPLICATION: Lobsters are an expensive menu item in restaurants. However, they are susceptible to being overcooked using conventional methods, producing a tough and rubbery texture. Sous vide cooking is reported to provide evenly cooked lobsters with a succulent and juicy texture. In this study, lobsters were sous vide cooked to reach a core temperature of 65 °C, and then maintained at that temperature for 10 min. The application of moderate processing pressures to vacuum-packaged raw lobsters prior to SV cooking altered some physicochemical attributes but has the potential to increase the availability of high-quality, minimally processed seafood with good consumer acceptability.

Impact of a Novel Cryoprotectant Blend on the Sensory Quality of Frozen Lobster (Homarus americanus).

Frozen storage of lobster meat (Homarus americanus) can result in undesirable quality changes that decrease consumer acceptability of these products. Current seafood industry methods use cryoprotective agents that contain phosphates including sodium tripolyphosphates (STPP). However, recent evidence suggests that cryoprotective mixtures that combine different carbohydrates and STPP can have equal or even greater cryoprotective properties compared to using STPP alone. The objective of this study was to compare the overall consumer acceptability of lobster meat stored for 6 months in different blends of these cryoprotective solutions. One hundred and seven panelists were recruited to score the acceptability of the lobster samples using nine-point hedonic scales. A check-all-that-apply (CATA) question containing 27 literature-informed, sensory descriptors was also used to identify terms frequently used to describe lobster meat. Analysis of variance analysis, indicated a significant increase for overall liking (22.1%, P < 0.0001), liking of flavor (23.6%, P < 0.0001) and texture (15.6%, P = 0.000) scores for samples stored in a novel carbohydrate blend plus sodium chloride (NaCl) and STPP compared to the water control. Subsequent penalty analysis revealed that overall liking scores were most positively associated with the attributes tender, sweet, moist and soft. Moreover, the attributes with the highest positive mean impact were more frequently used to describe lobster samples stored in solutions containing NaCl and the novel carbohydrate blend, as well as NaCl and STPP (Lobster-3 and Lobster-5 samples, respectively). PRACTICAL APPLICATION: The positive impact on the sensory quality of this novel blend of cryoprotective compounds (carbohydrates and NaCl) is proof of concept that this mixture is comparable, if not better than preservatives currently used by the seafood industry. Given the necessary regulatory approval and industry acceptance, lobster processors may consider this novel blend as a suitable alternative to freeze lobster products for up to 6 months.

Chemical composition, structural features, surface morphology and bioactivities of chitosan derivatives from lobster (Thenus unimaculatus) shells.

The chemical composition, structural features and bioactivities of chitosan derivatives were studied and reported here. Chitin and chitosan was extracted by chemical methods and yield was recorded 35% and 41%, moisture and ash has showed 7.4, 0.73, 1.2 and 0.79% and Ca was recorded high level (590 ppm). The IR spectrum has showed NH primary and secondary amines, OH group and several sugar stretching. N-acetyl glucosamine (GlcNAc), H-2 proton of glucosamine (GlcN), Anomeric protons, H-1 [GlcN (H-1D), GlcNAc (H-1A)] were noticed in 1H NMR and anomeric, methyl carbon atoms in 13C NMR. Rough surface, irregular block, crystalline with cluster and porosity structure was noticed by SEM observation. Antioxidant effect has showed good and concentration depended in four antioxidant assays. The α-amylase and ß-glucosidase enzyme inhibition effect of chitosan has showed promising and dose depend also anticoagulant potential. Chitosan could be used in pharmaceutical industry and tissue engineering.

Baseline assessment of contaminants in marine biota prior to remediation of industrial effluent impacted sediments in a former tidal estuary in Nova Scotia, Canada.

Contaminated sediments at a pulp mill and former chor-alkali effluent treatment facility in Nova Scotia, Canada will undergo remediation. However, baseline studies assessing contaminants in marine biota in the marine receiving environment are lacking. Historical qualitative and quantitative contaminant data in biota from Boat Harbour (a former tidal lagoon which was used to treat industrial effluent since 1967), and surrounding marine environment were reviewed to establish baseline pollution from industrial effluent and contaminated sediments. Elevated metal, dioxins and furan concentrations previously measured in marine biota needs updating to help inform pre-remediation monitoring. Selection of species, contaminants of concern and sampling locations were ad hoc and often inconsistent with environmental effects monitoring requirements under Canadian federal Pulp and Paper Effluent Regulations. These consolidated baseline data are required to determine historical impacts and to assist future monitoring during Boat Harbour sediment remediation to compare against.

Microplastics in the crustaceans Nephrops norvegicus and Aristeus antennatus: Flagship species for deep-sea environments?

Ingestion of microplastics (MPs) has been documented in several marine organisms, but their occurrence in deep-sea species remains almost unknown. In this study, MPs were investigated in two economically and ecologically key crustaceans of the Mediterranean Sea, the Norwegian lobster Nephrops norvegicus and the shrimp Aristeus antennatus. Both the species were collected from 14 sites around Sardinia Island, at depths comprised between 270 and 660 m. A total of 89 and 63 stomachs were analysed for N. norvegicus and A. antennatus respectively, and more than 2000 MPs-like particles were extracted and sorted for identification and characterization by µFT-IR. In N. norvegicus, 83% of the specimens contained MPs, with an average abundance of 5.5 ±â€¯0.8 MPs individual-1, while A. antennatus showed a lower frequency of ingestion (67%) and a lower mean number of MPs (1.66 ±â€¯0.1 MPs individual-1). Composition and size of particles differed significantly between the two species. The non-selective feeding strategy of N. norvegicus could explain the 3-5 folds higher numbers of MPs in its stomach, which were mostly composed of films and fragments derived by polyethylene and polypropylene single-use plastic items. Contrarily, most MPs in the stomachs of A. antennatus were polyester filaments. The MPs abundance observed in N. norvegicus is among the highest detected in Mediterranean species considering both fish and invertebrates species, and provides novel insights on MPs bioavailability in deep-sea habitats. The overall results suggest that both N. norvegicus and A. antennatus, easily available in common fishery markets, could be valuable bioindicators and flagship species for plastic contamination in the deep-sea.